U.S. patent application number 12/434797 was filed with the patent office on 2009-10-08 for low profile chassis and suspension.
Invention is credited to Earl Dallas Smith.
Application Number | 20090250895 12/434797 |
Document ID | / |
Family ID | 46304918 |
Filed Date | 2009-10-08 |
United States Patent
Application |
20090250895 |
Kind Code |
A1 |
Smith; Earl Dallas |
October 8, 2009 |
LOW PROFILE CHASSIS AND SUSPENSION
Abstract
A low profile chassis and suspension system for a road vehicle.
The chassis supports a payload section or cargo compartment, such
as for a delivery truck, ambulance, or shuttle bus. The chassis
includes a largely planar frame having a top surface which is
located beneath the rotational axes of the rear wheels. The wheel
suspension system is particularly compact and close to the road
surface. A trailing arm-type wheel support supports a stub axle in
a cantilevered fashion. A spring urges the wheel support apart from
the frame. A planar portion of the wheel support, the wheel support
pivot joints, and the spring are located beneath the rotational
axis of the wheel. In another embodiment, the frame includes a
recessed pocket which facilitates use of ramp for wheel chair
access.
Inventors: |
Smith; Earl Dallas;
(Greencastle, IN) |
Correspondence
Address: |
BINGHAM MCHALE LLP
2700 MARKET TOWER, 10 WEST MARKET STREET
INDIANAPOLIS
IN
46204-4900
US
|
Family ID: |
46304918 |
Appl. No.: |
12/434797 |
Filed: |
May 4, 2009 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11196870 |
Aug 4, 2005 |
7559400 |
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12434797 |
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09972536 |
Oct 8, 2001 |
6986519 |
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11196870 |
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09193501 |
Nov 17, 1998 |
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09972536 |
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08792972 |
Jan 31, 1997 |
5839750 |
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09193501 |
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60238790 |
Oct 6, 2000 |
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Current U.S.
Class: |
280/124.125 |
Current CPC
Class: |
B60G 3/14 20130101; B60G
11/27 20130101; B60G 2200/132 20130101; B60G 2202/152 20130101;
B60G 2300/38 20130101; B60G 5/04 20130101; Y10S 414/134
20130101 |
Class at
Publication: |
280/124.125 |
International
Class: |
B60G 9/00 20060101
B60G009/00 |
Claims
1.-24. (canceled)
25. An apparatus for a road vehicle comprising: a left rear wheel
rotatable about a first rotational axis; a right rear wheel
rotatable about a second rotational axis; a frame section having
right and left sides and a top surface located below said first
rotational axis and said second rotational axis, said frame section
defining a recessed pocket extending from an inboard portion of
said frame section to an outboard portion of said frame section
along one of the right or left sides and extending below the top
surface, said pocket being adapted and configured for wheelchair
access.
26. The apparatus of claim 25 wherein said frame section includes
an angled member along a boundary of the pocket, said member being
angled downward from an inboard portion of said frame section to an
outboard portion of said frame section.
27. The apparatus of claim 26 wherein the angle is more than about
5 degrees and less than about 18 degrees.
28. The apparatus of claim 27 wherein the angle is more than about
14 degrees and less than about 15 degrees.
29. The apparatus of claim 25 wherein said frame section includes a
substantially planar bottom surface underneath the recessed pocket,
and the bottom surface is less than about 9 inches above the road
surface.
30. The apparatus of claim 25 wherein the outboard edge of the
bottom boundary is less than about 9 inches from the road surface,
and the inboard edge of the bottom boundary is more than about 20
inches from the outboard edge of the bottom boundary.
31. The apparatus of claim 29 wherein said frame section includes
an outboard frame member parallel to the longitudinal axis of said
frame section and along an outboard boundary of the pocket, said
outboard frame member having a top surface that is more than about
6 inches above the road surface and less than about 9 inches above
the road surface.
32. The apparatus of claim 25 wherein said pocket is located in
front of said left and right wheels.
33.-45. (canceled)
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of U.S. patent application
Ser. No. 11/196,870, which is a continuation of U.S. patent
application Ser. No. 09/972,536, filed Oct. 8, 2001, which is a
continuation-in-part application of Ser. No. 09/193,501, filed Nov.
17, 1998, entitled LEAF SPRING WHEEL SUSPENSION SYSTEM, now
abandoned, which is a continuation of Ser. No. 08/792,972, filed
Jan. 31, 1997, entitled LEAF SPRING WHEEL SUSPENSION SYSTEM, which
issued as U.S. Pat. No. 5,839,750 on Nov. 24, 1998. This
application also claims priority to U.S. provisional patent
application Ser. No. 60/238,790, filed Oct. 6, 2000 and entitled
LOW PROFILE CHASSIS AND SUSPENSION. This application also claims
priority to application Ser. No. 09/318,428, filed May 25, 1999,
which issued as U.S. Pat. No. 6,398,251 on Jun. 4, 2002. All of the
above-referenced applications are incorporated herein by
reference.
BACKGROUND OF THE INVENTION
Field of the Invention
[0002] This invention relates to the field of wheel suspensions,
and particularly to wheel suspension systems that independently
support the wheels of a vehicle in which a wide and low cargo floor
is desired. This invention is an improvement to the wheel
suspension systems described in my earlier patents, namely, U.S.
Pat. No. 4,878,691, issued on Nov. 7, 1989, U.S. Pat. No.
4,934,733, issued on Jun. 19, 1990, U.S. Pat. No. 5,016,912, issued
on May 21, 1991, U.S. Pat. No. 5,275,430, issued on Jan. 4, 1994,
and U.S. Pat. No. 5,839,750, issued on Nov. 24, 1998, all
incorporated herein by reference.
[0003] For a variety of reasons, it is frequently desirable to have
the cargo floor of a trailer, van, or similar vehicle as low as
reasonably possible. A low floor provides for more efficient
transportation of cargo, giving a vehicle more useable, internal
space for given exterior dimensions. Also, a low floor placed close
to the road surface makes for easier access to the vehicle. These
and other advantages of a low cargo floor have motivated various
proposals for low vehicle floors.
SUMMARY OF THE INVENTION
[0004] One embodiment of the present invention is a unique
apparatus for placing the floor of a cargo compartment or payload
section of a vehicle close to the roadway surface. Examples of
cargo compartments and payload sections include the aft section of
delivery trucks, airport shuttle buses and ambulances.
[0005] In another embodiment of the present invention, there is a
novel configuration for a vehicle which includes a cab section with
a high mounted engine and high placed cab floor coupled to a low
profile chassis.
[0006] In yet another embodiment of the present invention, there is
a novel manner of supporting an exhaust pipe within a frame that
rides close to the road surface.
[0007] In a still further embodiment of the present invention,
there is an apparatus for a road vehicle which includes a pair of
frame sections with substantially planar top surfaces, and a planar
bottom surface on one of the frame sections which provides
increased ground clearance. A still further embodiment of the
present invention pertains to a frame section of a vehicle placed
below the rotational axes of the rear wheels, the frame section
defining a recessed pocket adapted and configured to provide
wheelchair access to the vehicle from a ramp.
[0008] In another embodiment of the present invention, there is a
front suspension for a road vehicle which includes a pair of
trailing arm supports attached to a driven front axle, and a
pivotal member which links a trailing arm on one side of the
vehicle with a frame member on the other side of the vehicle.
[0009] Yet another embodiment of the present invention pertains to
a hydraulic brake assembly for use on a wheel whose rotational axis
is above the top surface of a frame section. The hydraulic ports
and hydraulic lines for the brake assembly are oriented such that
they do not extend inward of the inboard surface of the brake
assembly.
[0010] In yet another embodiment of the present invention, a
vehicle including a rear frame with a top surface below rotational
axes of the rear wheels is coupled to a driven front axle. The
front axle receives power from an engine which is located aft of
the front axle.
[0011] Accordingly, one object of the present invention is to
provide a unique apparatus for transporting people and/or cargo in
a vehicle.
[0012] Further objects, embodiments, forms, benefits, aspects,
features, and advantages of the present invention can be obtained
from the description, drawings, and claims provided herein.
DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a perspective view of a pair of wheel suspension
systems constructed in accordance with one embodiment of the
present invention.
[0014] FIG. 2 is a side elevational view of the wheel assemblies
and wheels of FIG. 1 mounted to a vehicle frame, viewing outwardly
from inboard of the assemblies.
[0015] FIG. 3 is a top plan view of the wheel assemblies of FIG.
1.
[0016] FIG. 4 is a side elevational view of a frame and suspension
section of a vehicle according to another embodiment of the present
invention.
[0017] FIG. 5 is a top plan view of the vehicle section of FIG. 4
as taken along line 5-5 of FIG. 4.
[0018] FIG. 6A is a cross-sectional view of the vehicle section of
FIG. 5 as taken along line 6-6 of FIG. 5.
[0019] FIG. 6B shows the vehicle section of FIG. 6A supporting a
cargo compartment.
[0020] FIG. 7 is a partial cross-sectional view of a portion of the
vehicle section of FIG. 5 as taken along the line 7-7 of FIG.
5.
[0021] FIG. 8A is a side elevational view of a wheel support and a
portion of the vehicle section of FIG. 5 as viewed along line 8A-8A
of FIG. 5.
[0022] FIG. 8B is a side elevational view of the wheel support and
portion of the vehicle section of FIG. 8A including a reinforcing
doubler.
[0023] FIG. 9 is a perspective view of a wheel support according to
one embodiment of the present invention.
[0024] FIG. 10A is a side elevational view of a pivotal attachment
according to one embodiment of the present invention.
[0025] FIG. 10B is a side elevational view of another pivotal
attachment according to one embodiment of the present
invention.
[0026] FIG. 11 is an enlargement of the area within dotted oval 189
of FIG. 5.
[0027] FIG. 12 is a perspective view of a two-wheeled embodiment of
the present invention as used within a van.
[0028] FIG. 13 is a perspective view of a four-wheeled embodiment
of the present invention as used within a trailer.
[0029] FIG. 14 is a top plan view of a vehicle section in
accordance with another embodiment of the present invention.
[0030] FIG. 15 is a partial side view of the vehicle section of
FIG. 14 as taken along line 15-15 of FIG. 14.
[0031] FIG. 16 is a top plan view of a vehicle section in
accordance with another embodiment of the present invention.
[0032] FIG. 17 is a top plan view of a wheel support according to
one embodiment of the present invention.
[0033] FIG. 18 is a side elevational view of the wheel support of
FIG. 17.
[0034] FIG. 19 is a cross-sectional, perspective view of another
embodiment of the present invention.
[0035] FIG. 20 is a top plan view of a frame and suspension system
according to another embodiment of the present invention.
[0036] FIG. 21 is a top plan view of a frame and suspension system
according to another embodiment of the present invention.
[0037] FIG. 22 is a top plan view of a frame and suspension system
according to another embodiment of the present invention.
[0038] FIG. 23 is a top plan view of a frame and suspension system
according to another embodiment of the present invention.
[0039] FIG. 24 is a front, left side, and top perspective view of
another embodiment of the present invention.
[0040] FIG. 25A is a front elevational view of the embodiment of
FIG. 24.
[0041] FIG. 25B is a rear elevational view of the embodiment of
FIG. 24.
[0042] FIG. 25C is a left side elevational view of the embodiment
of FIG. 24.
[0043] FIG. 26 is a bottom planar view of the embodiment of FIG.
26.
[0044] FIG. 27 is a rear, top, and right side photograph of another
embodiment of the present invention.
[0045] FIG. 28 is a front, top, and left side photograph of the
embodiment of FIG. 27.
[0046] FIG. 29 is a partly sectional schematic representation of a
side elevational view of another embodiment of the present
invention.
[0047] FIG. 30 is a top plan view of an apparatus according to
another embodiment of the present invention.
[0048] FIG. 31 is an end elevational view of the apparatus of FIG.
30 as taken along line 31-31 of FIG. 30.
[0049] FIG. 32 is a side elevational view of the apparatus of FIG.
30 as taken along line 32-32.
[0050] FIG. 33 is a top, side perspective view of a portion of the
apparatus of FIG. 30.
[0051] FIG. 34 is a side elevational view of another embodiment of
the present invention.
[0052] FIG. 35 is a top plan view of an apparatus according to
another embodiment of the present invention.
[0053] FIG. 36 is a side and rear perspective view of a vehicle
incorporating the apparatus of FIG. 35.
[0054] FIG. 37 is a top, front, left side perspective view of the
apparatus of FIG. 30.
[0055] FIG. 38 is an enlargement of a portion of the apparatus of
FIG. 37.
[0056] FIG. 39 is a top perspective view of a portion of the
apparatus of FIG. 37.
[0057] FIG. 40 is a rear, side perspective view of a portion of the
apparatus of FIG. 37.
[0058] FIG. 41 is a side true perspective view of a wheel support
according to another embodiment of the present invention.
[0059] FIG. 42 is a top true perspective view of the wheel support
of FIG. 41.
[0060] FIG. 43 is a bottom true perspective view of a mirror-image
wheel support of the wheel support of FIG. 41.
[0061] FIG. 44 is a side perspective and cutaway view of a portion
of a wheel support, wheel, brake, and stub axle assembly according
to one embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0062] For the purposes of promoting an understanding of the
principles of the invention, reference will now be made to the
embodiment illustrated in the drawings and specific language will
be used to describe the same. It will nevertheless be understood
that no limitation of the scope of the invention is thereby
intended, such alterations and further modifications in the
illustrated device, and such further applications of the principles
of the invention as illustrated therein being contemplated as would
normally occur to one skilled in the art to which the invention
relates.
[0063] The present invention provides a wheel suspension system
which has an extremely low profile. The suspension system utilizes
a wheel support that is connected with the vehicle frame at points
of attachment on the frame which are spaced apart laterally,
thereby providing lateral support for the wheel. The wheel support
is pivotable between an uppermost position and a lowermost
position. One or two biasing means are included to maintain the
wheel support in an intermediate position and to absorb loads from
the wheel.
[0064] Referring in particular to FIG. 1, there is shown a wheel
suspension system constructed in accordance with the present
invention. The system includes a pair of wheels mounted to a
vehicle frame by respective wheel supports. The wheel supports are
maintained in position by a leaf spring secured between the wheel
support and the frame.
[0065] The two wheels are shown mounted on the same side of the
vehicle, and of course similar wheels and suspension systems are
used on the opposite side of the vehicle. It will further be
appreciated that the present invention is equally useful when only
one wheel is supported on each side of the vehicle. Also, the
embodiment of FIG. 1 utilizes a single leaf spring, but could
equally use separate biasing means serving the function of the
spring.
[0066] The wheels are attached to cross members of the vehicle
frame by wheel supports. The wheel supports attach to the cross
member at a pair of pivot points, with one pivot point being
inboard of the other pivot point. This lateral displacement of one
pivot point relative to the other promotes the lateral stability of
the wheel support. The frame cross members are held in position by
a longitudinal member of the frame.
[0067] The wheel support connects to the frame cross member on a
portion of the support that is largely horizontal and parallel to
the roadway. The wheel support also has a section that is largely
vertical relative to the roadway, to which the wheel, spring and
shock absorber are attached. The spring and shock absorber attach
to the vertical portion of the wheel support and also a vertical
member of the frame. The upright portion of the wheel support is
adaptable to springs such as the coil type, air bag type, or any
other type of spring that creates a spring force when its
attachment points are displaced relative to each other.
[0068] There is an additional spring that acts between the wheel
support and the frame. This spring is of the leaf type, and
attaches to both the horizontal portion of the wheel support and
also to the frame. In a preferred embodiment, the attachment of the
spring to the wheel support permits relative sliding of the spring
within the wheel support in the fore and aft directions, but
otherwise transmits spring forces created by the pivoting of the
wheel support relative to the frame cross member. Alternative
attachments of the leaf spring may be used, including an attachment
by which one end of the spring is secured to a wheel support and
the portion connected with the vehicle frame is allowed to slide
relative thereto. Additionally, a spring configuration and
attachment could be employed in which all attachments of the spring
prevent or allow for sliding movement.
[0069] It is a feature of the leaf spring design that a biasing
device is provided that fits generally within the typical vehicle
frame. The leaf spring is located interior of the frame perimeter.
It is also positioned below the upper surface of the frame, and
thereby does not intrude into space available above the frame for
the bed of the vehicle, e.g., the floor of a trailer or van. As
shown in FIG. 1, the leaf spring is conveniently received through
an opening in a frame member, thus accommodating the position of
the leaf spring and minimizing the space required for the
spring.
[0070] This leaf spring may be used simultaneously with adjacent
wheels. The spring can attach, slidably or not, to two wheel
supports and also be attached to a cross member of the frame
in-between the two wheel supports.
[0071] The present invention provides a wheel suspension system
useful in a variety of applications. The preferred embodiment is
characterized by a wheel support with a largely vertical portion
and a largely horizontal portion. The vertical portion is generally
outboard of the vehicle frame. The horizontal portion is below or
within much of the vehicle frame. Also, the shock absorber and
springs of the preferred embodiment are similarly situated either
outboard of much of the vehicle frame, or below or within much of
the vehicle frame. This general arrangement permits maximum
utilization of the area inboard and above most of the frame as
useful cargo area. The wheel suspension system is useful, for
example, for mounting the wheels of a trailer, or for the rear
wheels of a front-wheel drive vehicle, such as a van.
[0072] Referring in particular to FIG. 1, there is depicted a
preferred embodiment of the present invention in a perspective
view. Frame outboard longitudinal member 2, shown with an "L" cross
section, is a major structural member of the vehicle frame
traversing fore and aft along one side of the vehicle and defining
an outer perimeter of the frame. Attached to it are frame cross
members 4 and 6, located fore and aft of each other, respectively.
These cross members traverse the width of the vehicle, and
typically terminate at the mirror image wheel suspension system on
the other side of the vehicle frame. The frame cross members
include frame vertical members 5 and 7, respectively, located
outboard of longitudinal member 2.
[0073] Wheel suspension systems according to the present invention
are mounted to the vehicle frame in the following manner. The wheel
suspension systems include, for example, wheel supports 24 and 26.
The supports carry stub axles or the like to support wheels
thereon. In turn, the wheel supports are mounted to the vehicle
frame for pivoting about a horizontal axis, thereby allowing the
carried wheel to move up and down with respect to the vehicle
frame.
[0074] Located just aft of the cross members are wheels 8 and 10.
These wheels are attached to the wheel supports 24 and 26,
respectively, and are free to rotate about respective hubs. For
example, wheel 8 is mounted to hub 16 and is free to rotate about a
horizontal axis 12 (FIG. 3). This hub is attached to upright
portion 20 of wheel support 24.
[0075] The wheel support further includes means for attaching
pivotally to the vehicle frame. The support preferably has a
generally flat, horizontal portion 21 attached pivotally to frame
cross member 4 at inboard pivotal attachment 28 and outboard
pivotal attachment 30. The attachments preferably comprise a
bracket secured to the frame, and a bolt and nut received through
apertures in the bracket and the associated portion of the wheel
support. These two pivotal attachments are aligned to provide for
pivoting about a horizontal axis extending therethrough. The
pivotal attachments are also displaced laterally to enhance the
lateral stability of the wheel support, and therefore of the first
wheel 8.
[0076] A similar method is used to attach wheel 10 to frame cross
member 6. Hub 18, about which second wheel 10 is free to rotate, is
attached to upright portion 22 of wheel support 26. This wheel
support further includes a horizontal portion 23 which is pivotally
attached to frame cross member 6 at pivotal attachments 32 and 34.
The wheel support 26 is thereby pivotal with respect to the frame
about a horizontal axis extending through the pivotal attachments
32 and 34, and the wheel 10 is rotatable about an axis 14 (FIG. 3)
which extends parallel to the pivoting axis.
[0077] The upright portions of the wheel supports attach not only
to the hubs, but also continue around the forward upper quadrant of
the respective wheels and attach to spring and shock absorber
assemblies. As shown in FIGS. 2 and 3, air spring (air bag) 50 and
shock absorber 56 both connect support upright portion 20 to frame
vertical member 5. Air spring 50 is attached at face 51 of first
wheel support 24, and also at face 52 of first frame vertical
member 5, in conventional fashion. Shock absorber 56 is mounted in
a typical manner along side air spring 50, to first wheel support
24 at pivotal attachment 57, and to first frame vertical member 5
at pivotal attachment 58. As wheel support 24 rotates about pivots
28 and 30, the distance between upright portion 20 and vertical
member 5 changes. The air bag and shock absorber accommodate this
movement and cushion the pivoting of the wheel support.
[0078] An alternate to the spring and shock absorber arrangement
utilizes a coil spring 60, as shown attached between wheel support
26 and frame vertical member 7 in conventional fashion. This spring
attaches to front spring mount 62 of vertical member 7, and to rear
spring mount 61 of wheel support 26. When utilizing a coil spring,
the shock absorber could be attached alongside the spring, similar
to the positioning shown for shock absorber 56, or it could be
attached coaxially with the coil spring. Shock absorber 66 is shown
mounted between frame vertical member 7 and wheel support 26 inside
the coils of coil spring 60.
[0079] Additionally spring support for the wheel occurs in respect
to the horizontal portions of the wheel support members. The
horizontal portion is configured to be substantially flat and to
underlie the vehicle frame. It is a feature of the present
invention that such a compact wheel support is also supportable in
a manner to further enhance the low profile of the overall
suspension in comparison to the vehicle frame.
[0080] The wheel support engages a leaf spring 70 that is secured
between the support and the vehicle frame. Each wheel support can
be combined with an individual leaf spring. Alternatively, pairs of
wheel supports can be accommodated by a single leaf spring, as
shown in the drawings. In general, a wheel support includes a leaf
spring receiving member for connection with an end of the leaf
spring. Leaf spring 70 is shown having a forward portion received
within a narrow slot comprising a leaf spring forward attachment
78. Leaf spring 70 continues in the aft direction, attaching to the
frame by means of the frame attachment 74 through which it passes.
Aft of that location the leaf spring includes a portion received
within the rear attachment 72 defined by the wheel support 26.
[0081] Frame attachment 74 prevents lateral, longitudinal or
vertical motion of the leaf spring at the point of attachment.
However, pivoting is permitted about the lateral access established
by frame attachment 74.
[0082] As wheel support 24 pivots about the axis defined by the
attachments 28 and 30, forward attachment 78 of the wheel support
moves in an arc relative to cross member 4. The distance between
attachments 74 and 78 changes as the wheel support pivots.
Attachment 78 permits sliding of leaf spring 70 in the fore and aft
directions. Thus, a change in the fore/aft distance between
attachments 74 and 78 does not result in the creation of spring
load from spring 70. However, attachment 78 does resist any change
in the vertical distance between attachments 78 and 74. Thus,
rotation of the wheel support results in a change in spring load of
spring 70 for the vertical component of movement.
[0083] Although the preferred embodiment depicts a single leaf
spring attached near its center in providing support to wheel
supports both in front and behind it, it is also possible to use a
single leaf spring for each wheel support. For example, it would be
possible to remove all portions of leaf spring 70 aft of attachment
74, and have the remainder support only first wheel support 24.
Similarly, it would also be possible to remove all portions of leaf
spring 70 forward of attachment 74, thus providing support only to
second wheel support 26. Thus, leaf spring 70 could provide
independent support for each wheel support, and the attachment of
that independent leaf spring, could either be forward or aft of the
respective wheel rotational axis.
[0084] Alternate embodiments of the present invention shown in
FIGS. 4-18 also provide a wheel suspension system which has an
extremely low profile. These alternate embodiments utilize a wheel
support that is connected by a pair of pivotal attachments to the
vehicle frame. The wheel support supports a wheel for rotation
about a rotational axis. The rotational axis is located above the
pivotal attachments and above the transverse frame structure which
lowers the profile of the wheel support and permits additional
cargo-carrying volume above the wheel support. The pivotal
attachments are spaced apart laterally, thereby providing lateral
support for the wheel. The wheel support is pivotal between a
first, uppermost position and a second, lowermost position. The
pivot axes of the two pivotal attachments are generally coincident,
and are preferably arranged such that the wheel support pivots in a
pitching direction relative to the vehicle.
[0085] Some of these embodiments incorporate a spring such as an
airbag, leaf spring, or coil spring for biasing the wheel support
to a position intermediate of the first and second positions. The
spring is placed between a spring support of the vehicle frame and
a spring support of the wheel support, and is placed beneath the
rotational axis of the wheel and preferably inward of the wheel and
tire. This placement of the spring helps increase useable cargo
carrying volume for the vehicle and simplifies the structural
support necessary to support the biasing loads by utilizing planar
portions of the vehicle frame to support the spring. In addition,
some embodiments orient the shock absorber in a generally
horizontal position beneath the rotational axis of the wheel. This
placement of the shock simplifies the structure of the wheel
support and also the upright structures of the frame that houses
the wheels. In some of those embodiments with horizontal shock
absorbers placed below the wheel rotational axis, the biasing
mechanism includes either an air bag, or one or more leaf springs
coupled to both a wheel support and a cross member of the vehicle
frame. In yet other embodiments, a leaf spring couples to adjacent
wheel supports and to the vehicle frame.
[0086] Referring to FIGS. 4-6, a vehicle frame and suspension
section 98 with a longitudinal axis X includes a wheel support 100
which rotatably supports a wheel 102 and tire 104. Wheel support
100 is pivotally attached to a cross member 106 of a transverse
frame structure 116 by a first pivotal attachment 108 and a second
pivotal attachment 110. Pivotal attachments 108 and 110 couple
wheel support 100 to frame section 98, and are displaced laterally
from one another so as to provide stability to wheel support 100.
Pivotal attachments 108 and 110 are pivotal about first axis 109
and second axis 111, respectively. Pivotal axes 109 and 111 are
preferably coincident with each other and are preferably oriented
transverse to the direction of motion of the vehicle. Wheel support
100 is thus pivotally attached so as to permit pitching motion of
wheel support 100. Wheel support 100 includes a generally upright
portion 112 which supports a spindle, or stub axle, 114 about which
wheel 102 rotates. The present invention contemplates spindles,
hubs, stub axles, and other similar devices known to those of
ordinary skill in the art as means for rotatably supporting a wheel
on the wheel support.
[0087] Frame and suspension section 98 includes a row of tires 104
on either side of a transverse frame structure 116. Transverse
frame structure 116 generally supports the vehicle cargo or utility
section directly above it, as best seen in FIGS. 12 and 13.
Referring again to FIGS. 5 and 6A, transverse frame structure 116
includes laterally disposed transverse frame sides 118 and 120.
Attached to first transverse frame side 118 is a first upright
frame structure 122. Attached to second transverse frame side 120
is a second upright frame structure 124. Frame structures 124, 116,
and 122 form a generally U shape, as best seen in FIG. 6A, with
transverse structure 116 being attached to the bottoms of the
opposing upright frame structures 124 and 122. The top surface of
transverse structure 116 preferably defines a plane that is located
generally at or below the rotational axis of the wheels.
[0088] Wheels 102, shock absorbers 136, spindles 114, and upright
portion 112 of wheel support 100 are disposed within upright
structures 122 and 124. Spindle 114 supports one or more wheels 102
disposed within the upright frame structures. Spindle, or stub
axle, 114 is not an axle that extends across transverse frame
structure 116. By not having an axle spanning between upright frame
structures 122 and 124, it is possible to have more cargo-carrying
volume within the vehicle. Transverse frame structure 116 can thus
be located below the rotational axes of the wheels 102, and cargo
can be carried below the rotational axes also.
[0089] Transverse frame structure 116 preferably includes a cross
member 106 for each pair of wheel supports 100. Cross members 106
are attached to longitudinal members 126 and sides 120 and 118 by
corner reinforcements 128. In addition, longitudinal members 126
are also interconnected to members 106 preferably with
reinforcements 130. Frame spring supports 132 of transverse frame
structure 116 are generally planar portions in one embodiment which
extend inward preferably from either first side 118 or second side
120 to longitudinal members 126. Preferably, spring supports 132
are laterally disposed inwardly from the wheel being supported.
Portions of wheel supports 100 for supporting a spring are located
below frame spring supports 132. Disposed between each wheel
support 100 and frame spring support 132 in one embodiment is an
air spring 133. Frame spring support 132 provides a support for air
spring 133.
[0090] Although what has been shown and described is a specific
arrangement of cross members and longitudinal members with
reinforcements, the present invention also contemplates other
arrangements for a transverse frame structure as would be known to
one of ordinary skill in the art. Although welding is a preferable
means of joining various members of frame and suspension section
98, the present invention also contemplates other joining and
integrating methods, including fusion, bonding, brazing, bolting,
casting, molding, and similar methods known in the art. Also, those
of ordinary skill in the art will recognize that the cross members
and longitudinal members can have a variety of cross sectional
shapes, such as for C channels, I beams, L shapes, rectangular
shapes, and others.
[0091] Wheel support 100 is pivotally attached to cross member 106
by a pair of pivotal supports 108 and 110. Supports 108 and 110
permit pivoting of wheel support 100 in a pitching direction about
a pivotal axis that coincides with first axis 109 of support 108
and second axis 111 of support 110. Inboard pivotal attachment
member 180 of support 100 is preferable releasably fastened to
inner pivot 108a of support 108. Inner pivot 108a is coupled to
outer support housing 108c through a rubber bushing 108b. Inner
pivot 108a is able to pivot relative to housing 108c by twisting
rubber bushings 108b. In a similar fashion, an inner pivot 110a of
pivotal attachment member 110 is able to pivot relative to the
housing 110c by twisting a rubber bushing 110b.
[0092] Wheel support 100 supports a wheel for rotation about a
rotational axis 158, and is arranged and constructed such that
there is usable cargo volume below the rotational axis of the
wheel, as best seen in FIGS. 6A, 12, and 13. Horizontal portion 168
of wheel support 100 lies generally below the volume useful for
cargo. Pivotal attachments 108 and 110, which pivotally support
wheel support 100, have pivot axes 109 and 111, respectively, that
are located below rotational axis 158. In one embodiment of the
present invention, pivot axes 109 and 111 are preferably parallel
to rotational axis 158, as best seen in FIG. 8A.
[0093] Wheel support 100 pivots about pivot axis 109 and 111 in a
pitching direction relative to the vehicle, and is pivotal between
an uppermost position and a lowermost position. Wheel support 100
is biased to a position between the uppermost and lowermost
positions, preferably by air spring 133. However, the present
invention also contemplates the use of other means for biasing the
wheel support, including by way of example one or more coil springs
or one or more leaf springs. The one or more springs bias wheel
support 100 to a position between the uppermost and lowermost
positions by urging spring support 156 of wheel support 100 apart
from frame spring support 132 of the vehicle frame.
[0094] In one embodiment, spring supports 156 and 132 generally
face each other and are part of a structural load path for the
spring forces from spring 133. Preferably, spring supports 156 and
132 are disposed laterally inward from the wheel being supported,
although the present invention also contemplates spring supports
disposed laterally inward from the tire being supported. Spring
supports 156 and 132 are preferably generally planar in those
embodiments utilizing air springs with planar attachment surfaces.
However, the present invention also contemplates those embodiments
in which spring supports 156 and 132 are constructed and arranged
to compatibly support other types springs, including, for example,
leaf springs and coil springs.
[0095] Referring to FIG. 7, upright frame 124 is joined to
transverse frame structure 116 along second side 120 of frame
structure 116. In one embodiment, vertical wall section 144 of
upright structure 124 is angled outwardly about 4 degrees from the
vertical, so as to permit additional cargo space. Wall section 144
is preferably fused to a longitudinal member 150 in the shape of a
C channel that extends along side 120.
[0096] Air spring 133 is preferably fastened to attachment plate
152 by fasteners (not shown) along upper contact face 154a of air
spring 133, contact face 154a being one end of air spring 133.
Attachment plate 152 is preferably fastened to spring support 132
of frame section 116 by fasteners (not shown). One side of spring
support 132 is preferably welded to a longitudinal member at 126,
and the other side of spring support 132 is preferably welded to
longitudinal member 150, the present invention contemplating other
means known to those of ordinary skill in the art for coupling the
spring support to the transverse frame section.
[0097] Air spring 133 is preferably fastened by fasteners (not
shown) to spring support 156 of wheel support 100 along a lower
contact face 154b of air spring 133, contact face 154b being the
other end of air spring 133, this end of air spring 133 being
between the second spring support 156 and the rotational axis of
the wheel. Thus, upper contact face 154a is coupled to and in
contact with a first spring support 132 and lower contact face 154b
is coupled to and in contact with a second spring support 156.
[0098] Although it is preferable to couple lower face 154b of the
air spring with fasteners to attachment member at 156, coupling is
not necessary provided lower face 154b is in contact with spring
support 156. Attachment members 156 and 132 support biasing loads
from spring 133.
[0099] Upright portion 112 of wheel support 100 supports spindle
114. Spindle 114 is attached at a fastener attachment pattern 160
to upright portion 112. Spindle 114 defines a rotational axis 158
that is generally horizontal and preferably parallel to the pivotal
axis of wheel support 100. However, the present invention also
contemplates those embodiments in which the rotational axis of the
wheel and the pivotal axis of the wheel support are not parallel. A
hub 162 is mounted to spindle 114 by a pair of bearings 163. A
brake drum 164 is fastened to hub 162, and provides a braking
surface for a pair of brake shoes 166.
[0100] Upright portion 112 of wheel support 100 in one embodiment
includes a support structure 134. A shock absorber 136 is pivotally
coupled to support structure 134 by a coupling end 138 that
attaches to ears 140 of support structure 134. Attachment ears 140
for coupling to shock absorbers 136 are attached to support plate
structure 183 of support structure 134 as best seen in FIGS. 8A and
8B. As seen in FIGS. 6A-7, the other coupling end 142 of shock
absorber 136 is pivotally coupled within upright frame structures
124 and 122. Shock absorber 136 and support structure 134 are
located forward of the rotational axis of wheel 102, and above the
pivot axis of wheel support 100 in some embodiments.
[0101] Support structure 134 preferably provides features for
attachment of various components, including braking system
components (not shown). As best seen in FIG. 9, support 134
includes support plates 183 which incorporate fastening patterns
182 and 184 for support and attachment of various components,
including braking system components (not shown). Top support plate
183 also defines a slot 186 through which brake system linkages
(not shown) pass onto the braking system components for wheel
102.
[0102] Referring to FIG. 8A, a side elevational view of wheel
support 100 and a portion of frame 116 is shown. Some embodiments
of wheel support 100 include a stiffening member 167 generally in
the shape of a "W" to provide stiffness and strength along spring
support 156 and to better distribute loads from air spring 133 into
wheel support 100. However, the present invention also contemplates
those wheel supports 100 in which alternative structure is used to
provide sufficient support for spring biasing loads imposed upon
spring support 156, including by way of example only, increased
thickness for spring support 156, stiffening ribs attached or
incorporated into spring support 156, V-shaped and I-shaped
structural members, and various other equivalents known to those of
ordinary skill in the art.
[0103] FIG. 8B depicts a side elevational view of an embodiment of
wheel support 100 capable of supporting two wheels. A doubler plate
167 is installed on upright section 112 between section 112 and
wheel spindle 114. Doubler plate 167 provides an improved
distribution of load from spindle 114 within upright section 112.
In one embodiment of the present invention, upright section 112 is
constructed from A-36 steel plate of about one and one quarter inch
thickness. Doubler plate 167 is constructed from A-36 steel plate
of approximately one half inch thickness. In other embodiments the
doubler may not be needed, upright portion 112 being fabricated
from thicker material or higher strength material, incorporating
reinforcing ribs, or otherwise suitably strengthened.
[0104] FIG. 9 is a perspective view of a wheel support according to
one embodiment of the present invention. Wheel support 100 includes
a generally horizontal portion 168 attached to upright portion 112.
Horizontal portion 168 includes spring support 156 for supporting
air spring 133. In one embodiment, spring support 156 includes a
fastener pattern 174 for fastening air spring 133 to wheel support
100. However, in some embodiments of the present invention spring
support 156 is not fastened to air spring 133. Horizontal portion
168 also preferably includes a slot 176 or other means to provide
clearance for an air line for pressurizing and depressurizing air
spring 133. In some embodiments, the center of air spring 133 is
located between the rotational axis of the wheel and the pivotal
axis of the wheel support, as best seen in FIG. 4.
[0105] Referring again to FIG. 9, a reinforcing member 170, which
may include one or more distinct pieces, has a generally square
cross-section in one embodiment and supports some of the edges of
spring support 156. A reinforcing member 171 with a C-shaped
cross-section is attached to one end of reinforcement member 170
and also to upright portion 112. Reinforcement member 171 includes
a pair of inboard pivotal attachment members 180 and a pair of
outboard pivotal attachment members 178. Inboard attachment members
180 define holes 181 for coupling to second pivotal attachment 108.
Outboard pivotal attachment members 178 preferably define threaded
holes 179 for fastening to first pivotal attachment 110. In one
embodiment, holes 179 are oriented about ninety degrees from holes
181.
[0106] Multiple corner reinforcements 172a and 172b attach
reinforcement member 170 to upright portion 112 in one corner. A
corner reinforcement 172a similarly attaches member 171 to upright
portion 112. A reinforcement plate 173 is fused to one end of
reinforcement member 171 near upright portion 112 so as to better
distribute stresses within support 100. Plate member 173 and corner
reinforcement 172a enhance the stiffness and strength of the load
path from spindle 114 to outboard pivotal attachment members 180.
In one embodiment of the present invention, the included angle 175
from upright section 112 to spring support 156 is about ninety and
three fourths degrees, so as to provide about three fourths of a
degree of positive camber when not loaded by the weight of the
vehicle. Although a specific arrangement of reinforcement members
has been shown and described for wheel support 100, those of
ordinary skill in the art will recognize equivalent methods of
providing sufficient strength and stiffness.
[0107] FIGS. 10A and 10B depict side elevational views of pivotal
attachments according to one embodiment of the present invention.
Pivotal attachments 108 and 110 include pivotal inner support
member 108a and 110a, respectively, that are supported from
stationary outer members 108c and 110c, respectively, by
elastomeric bushings 108b and 110b, respectively. Inner supports
108a and 110a are able to pivot about pivot axes 109 and 111,
respectively. Inner pivotal member 108a includes a pair of through
holes 108d for coupling attachment assembly 108 by fasteners to
attachment members 180 of wheel support 100. In one embodiment
fastener holes 108d are oriented such that their centerlines are
inclined from the horizontal as indicated by angle 188. Fastener
holes 110d of pivotal inner member 110a, likewise used for
fastening pivotal attachment 110 to attachment members 178 of
support 100, are inclined from vertical in one embodiment as
indicated by angle 188. In one embodiment of the present invention
angle 188 is about seven and one half degrees, and may be as large
as about fifteen degrees. The offset angle 188 of the pivotal
attachments preferably corresponds to a similar offset angle for
wheel support 100 prime, as seen in FIG. 4, as will be discussed
later. In other embodiments, angle 188 is about zero degrees.
[0108] Although what has been shown and described are pivotal
attachment assemblies in which an inner pivoting member is
elastomericly mounted to an outer housing, the present invention
contemplates other type of pivotal attachment assemblies. By way of
example only, the present invention also contemplates pivotal
attachment assemblies in which a pivotal inner member is coupled by
a bearing, such as a ball bearing or plane bearing, to an outer
casing. By further way of example, the outer casing may be a cast,
molded, adhered, welded, or otherwise fixedly attached member to
the transverse frame section 116. By further way of example, the
inner pivoting member may be cast, molded, adhered, welded, or
otherwise fixedly attached or otherwise made integral with wheel
support 100, thus eliminating the need for attachment members such
as members 180 and 178. Yet other varieties of pivotal attachments
are known to those of ordinary skill on the art. It is preferable
that the pivotal attachments include a feature that permits spacing
apart of the pivotal attachment from either frame section 116 or
wheel support 110 so as to permit adjustment of wheel camber and
toe-in. One embodiment of the present invention which includes such
adjustment features will now be described.
[0109] Pivotal attachments 108 and 110 are preferably attached by
readily removable fasteners 177 to cross member 106, as seen in
FIG. 11. Pivotal attachment 110 supports the outboard side of wheel
support 100 via outboard pivotal attachment members 178. Pivotal
attachment 108 supports the inboard side of wheel support 100
through L-shaped inboard pivotal attachment members 180. Pivotal
attachment members 178 and 180 are preferably welded or otherwise
attached, cast, or molded within channel member 171 of wheel
support 100, as best seen in FIGS. 8A and 9.
[0110] Referring again to FIG. 11, pivotal attachment 110 is
capable of being spaced apart from cross member 106 of frame 116 so
as to move pivot axis 111 in a longitudinal direction relative to
the vehicle. This spacing may be accomplished, for example, by
insertion of a shim between pivotal attachment 110 and cross member
106. In addition, wheel support 100 may be spaced apart from
pivotal attachment 110 by insertion of shims between attachment
members 180 and pivotal inner member 110a. By spacing apart
attachment assembly 110 from frame 116, and/or spacing apart wheel
support 100 from attachment assembly 110a, the toe-in of the
supported wheel 102 can be adjusted.
[0111] Second pivotal attachment 108 is similarly coupled to cross
member 106 of frame 116, and may be spaced apart from frame 116 so
as to move pivot axis 109 longitudinally relative to the vehicle.
Thus spacing apart pivotal attachment 108 from frame 116 adjusts
the toe-in of the wheel 102 supported by support 100. In one
embodiment the present invention contemplates the use of shims for
adjusting both camber and toe-in, including shims fabricated from
sheet or plate material, and also shims in which the shim faces are
not parallel, but are angled in proportion to the desired toe-in or
camber angle. Further, the pivotal attachments are releaseably
coupled to the transverse frame section and also to the wheel
support so that the shimming may be performed easily and
repeatedly, as desired, without the need, for example, to remove
welded attachments.
[0112] Fastener attachment holes 108d are positioned about ninety
degrees relative to fastener holes 110d. Also, fastener holes 181
of inboard attachment members 180 are oriented about ninety degrees
relative to fastener holes 179 of outboard attachment members 178,
as best seen in FIG. 9. As a result, spacing apart inner pivotal
member 108a from attachment members 180 moves wheel support 100 in
a different direction than that achieved by shimming between inner
member 110a and attachment members 178. Spacing apart inner pivot
108a from attachment members 180 adjusts the camber of the wheel
102 supported by wheel support 100.
[0113] Although what has been described is an embodiment which
includes a pivotal attachment 108 which can be shimmed or otherwise
manipulated so as to adjust camber or toe-in and another pivotal
attachment 110 which can be manipulated to adjust toe-in, the
present invention also contemplates those embodiments in which
there are two pivotal attachments each permitting adjustment of
camber or toe-in or two pivotal attachments each permitting
adjustment of only camber or toe-in. Further the present invention
also contemplates embodiments in which neither pivotal attachment
permits adjustment of either camber or toe-in, or in which only one
pivotal attachment permits adjustment of either camber or
toe-in.
[0114] In one embodiment of the present invention, spring support
156 of wheel support 100 is preferably inclined from the horizontal
for improved airbag characteristics, as indicated by angle 188 of
FIG. 4. Wheel support 100x is shown in the inclined position during
operation of frame and suspension section 98 on a level surface.
The tire rotatably supported from wheel support 100y is shown at
full jounce over an irregularity in the roadway such that wheel
support 100y has pitched up and second spring support 156y is
generally parallel to first spring support 132y and also to roadway
190.
[0115] In this embodiment pivotal attachments 108 and 110 include
inner pivoting members 108a and 110a, respectively, which have an
included angle 188, as best seen in FIGS. 10A and 10B. By
incorporating an offset angle 188 into pivotal attachments 108 and
110 that is the same as the offset angle 188 of wheel support 100
prime, stress within elastomeric bushing 108b and 110b is kept to a
minimum during normal operation. Other embodiments of pivotal
attachments incorporating by way of example plane, roller, or ball
bearings in place of the elastomeric bushings would not need an
offset angle 188. The present invention also contemplates pivotal
attachments 110 and 108 in which the offset angle of the pivotal
attachments is different than the offset angle of the wheel support
relative to the roadway during normal operation, with the
difference in the pivotal attachment offset angle and the wheel
support offset angle being provided by angled attachment faces to
attachment members 180 and 178.
[0116] One embodiment of the present invention contemplates an
angle 188 of about 7.5 degrees between first spring support 132 and
second spring support 156 during typical operation of the
suspension system on a level roadway 190. Having an included angle
188 of about 7.5 degrees provides an acceptable range of air spring
characteristics and internal air pressure in one embodiment, and
permits placement of certain types of air springs below the cargo
compartment of the vehicle. However, the present invention
contemplates a range for angle 188 from about 0 degrees to about 15
degrees. For example, a cast wheel support with different
dimensions provides equally acceptable air spring characteristics
and internal pressure with an angle 188 of about zero degrees, such
that faces 154a and 154b of air spring 133 are generally parallel
during operation of the suspension on a level road.
[0117] In another embodiment of the present invention, there is a
suspension control system for maintaining the ride height of the
vehicle as the weight of the vehicle changes, and also for changing
the air pressure in the air spring in response to pivoting of the
wheel support. A linkage (not shown) attached to both wheel support
100 and the upright frame structure provides a control input to a
pneumatic valve (not shown), such as a Neway Model 9005-4007
leveling valve. In response to movement of the linkage, the valve
places air spring 133 in fluid communication with either ambient
air or with a source of air pressure such as air tank 192, which is
provided pressurized air from an air compressor. Movement of wheel
support 100 relative to the vehicle frame causes the valve to
increase or decrease the air pressure in air spring 133. The
control system adjusts the air pressure within air spring 133 so as
to maintain the wheel support at a predetermined angle relative to
the vehicle frame, and also to maintain a predetermined orientation
of the vehicle.
[0118] Although FIGS. 4, 5 and 6A depict an embodiment of the
present invention which includes six wheel supports 100 supporting
six wheels 102, some embodiments of the present invention include a
single wheel support 100 supporting a single wheel 102. Other
embodiments of the present invention, such as frame and suspension
section 98' shown as part of a van vehicle 200 in FIG. 12, include
two wheel supports 100 each supporting a single wheel 102. In yet
another embodiment of the present invention shown in FIG. 13, a
frame and suspension section 98'' including four wheel supports 100
supporting four wheels 102 is shown in a trailer section of a
vehicle 202. Further, some other embodiments of the present
invention include a wheel support 100 that support a pair of wheels
102 to maintain adequate load margin in the tires when supporting a
heavy cargo load.
[0119] The frame and suspension sections shown herein may be built
modularly and slidingly coupled to a cargo compartment. As shown in
FIG. 6B, some embodiments of frame and suspension section 98
include a pair of rails 117 coupled to upright frame structures 122
and 124. These rails 117 slidingly engage a pair of receiving
C-channels 119 arranged on the underside of the trailer section of
vehicle 202. After the sliding insertion, the floor of the trailer
section is below the rotational axes of the wheels, the C-channel
of longitudinal member 150 being replaced with an L-angle
longitudinal member. The coupling of rails 117 and C-channels 119
limits lateral and vertical motion of the frame and suspension
section relative to the cargo compartment. A locking arrangement
(not shown) such as a plurality of locking shear pins inserted
through matched holes limits fore and aft relative movement.
Although a particular arrangement has been shown for coupling a
frame and suspension section of the present invention to a trailer,
those of ordinary skill in the art will recognize other
arrangements, including those in which the frame and suspension
section and trailer are not slidingly coupled.
[0120] FIGS. 14-16 depict another embodiment of the present
invention in which the shock absorber is located below the
rotational axis of the wheel. A wheel support 100' includes a
horizontal portion 168' coupled to an upright section 112'.
Horizontal portion 168' includes a spring support 156' receiving
and coupling to a spring which urges wheel support 100 away from
transverse frame structure 116. The use of (') and ('') indicate
elements of the invention substantially the same as previously
described for that element, except for the changes as noted.
[0121] FIGS. 14-15 depict an embodiment in which a leaf spring 70
urges a pair of wheel supports 100' from transverse frame structure
116. Leaf spring 70 includes a first end 70a clamped by a pair of
bolts to spring support 156'. A second end 70b is in sliding
contact with spring support 156' of the aft-most wheel support.
Ends 70a and 70b are located between their respective second spring
support 156' and the rotational axis of the wheel. The center 70c
of leaf spring 70 is fastened to a portion of cross-member 106 of
transverse frame structure 116 which is the frame spring support.
Pitching movement of either the forward-most wheel support 100' or
the aft-most wheel support 100' is resisted by a biasing force from
the center of the leaf spring.
[0122] Although a particular arrangement for contacting leaf spring
70 with wheel supports 100 and transverse frame structure 116 has
been shown and described, those of ordinary skill in the art will
recognize other suitable arrangements. For example, both ends of
spring 70 could be clamped to the wheel supports, or both ends
could be slidable on the wheel support. Further, the method of
clamping leaf spring 70 can be one or more through fasteners, an
example of which is depicted at 70c, or a fastened strap, as
depicted at 70a, or other methods known in the art for clamping a
leaf spring to a structure. As another example, spring 70 can pass
through a frame attachment 74 as shown in FIG. 1. Further, although
FIG. 14 depicts a leaf spring 70 acting upon two adjacent wheel
supports, the present invention also contemplates those embodiments
in which a leaf spring acts upon a single wheel support. As
depicted in FIG. 16, an alternate embodiment includes an air spring
133 acting on both spring support 156' of wheel support 100' and
also on spring support 132' of transverse frame structure 116.
[0123] Referring to FIGS. 14-15, shock absorber 136 is located
beneath the rotational axis of the wheel so as to further simplify
the structure of the wheel support, upright frame structures 122
and 124, and to further increase the cargo-carrying capability of
the vehicle. Placement of shock absorber 136 is such that it acts
upon horizontal portion 168' at wheel support 100', and permits
elimination of support structure 134 and a generally simplified
upright structure 112'. Shock absorber 136 is actuatable about an
axis 137a, which is generally oriented horizontally as best seen in
FIG. 15.
[0124] Shock absorber 136 has a first end 136a which is pivotally
coupled to a portion of transverse frame structure 116, such as
cross-member 106 or longitudinal member 126', through an attachment
ear 140. A second end 136b of shock absorber 136 is pivotally
attached to one end of a lever arm 222. Lever arm 222 is pivotally
secured to pivot 224 which is attached to transverse frame
structure 116, such as by a bracket 226 in a manner well known in
the art. Lever arm 222 pivots about pivot axis 221. The other end
of lever arm 222 defines a slot 228. Pinned bushing 229 is slidable
in slot 228. Pinned bushing 229 is secured into a boss 220 of wheel
support 100'.
[0125] Upward pitching of wheel support 100' results in compression
of shock absorber 136 and sliding of pin 229 within slot 228.
Downward pitching of wheel support 100' relative to transverse
frame section 116 results in extension of shock absorber 136.
Pinned bushing 229 and lever arm 222 are fabricated from hardened
steel so as to minimize wear from sliding. Further, although an
embodiment has been described and depicted in which shock absorber
136 compresses during upward pitching of wheel support 100', those
of ordinary skill in the art will recognize other arrangements of
pivoting lever arms that will suitably dampen the motion of wheel
support 100' by extending during upward pitching.
[0126] FIGS. 17-18 depict a substantially cast wheel support 100''
according to another embodiment of the present invention. Wheel
support 100'' includes a horizontal portion 168'' cast integrally
with an upright portion 112''. A spring support 156'' within
horizontal portion 168'' receives loads from a spring, and is
reinforced by a plurality of cast stiffening ribs 169''. A cast
reinforcing member 170'' stiffens and strengthens wheel support
100''. Attachment members 178'' and 180'' are cast integrally with
wheel support 100''.
[0127] A support structure 134'' for attaching a shock absorber and
brake system components is integrally cast with upright portion
112''. Upright portion 112'' also includes a cast spider 239 which
includes an attachment pattern of holes 240, 242, and 244 for
support of brake system components (not shown) including brake
shoes and an S-cam. The toe-in of wheel support 100'' is adjustable
by shimming in a manner as previously described. Camber is
adjustable by incorporating slots in stationary outer members 108c
and/or 110c of the pivotal attachments. The slots permit the
orientation of outer member 108c or 110c to be adjusted relative to
cross-member 106. This orientation is maintained by a friction fit
provided by fasteners 177.
[0128] Yet other alternate embodiments of the present invention
include a wheel support and a disc brake as part of a wheel
suspension system. As shown in FIG. 19, an upright section 112' is
bolted to a spindle 114 by fasteners through fastener attachment
pattern 160. A rotating hub 162 is bearingly supported on spindle
114. Coupled to hub 162 is a vented disc assembly 165 comprised of
opposing rotor plates 165a and 165b. A caliper assembly 159
supported by upright portion 112' includes two friction pads 161
which are actuated against vented disc 165 so as to slow the
vehicle. For sake of clarity, only one friction pad 161 is shown.
Those of ordinary skill in the art will recognize the applicability
of disc brakes to the many embodiments of the present
invention.
[0129] FIGS. 20, 21 and 22 depict variations of the suspension
systems shown in FIGS. 3, 5 and 14, respectively, in which the
wheels on one side of the vehicle are longitudinally staggered, or
spaced apart, relative to wheels on the other side of the vehicle.
By staggering the wheels as shown, a softer ride can be presented
to the cargo or occupants, and less wear is imposed upon the
roadway, especially a roadway with a disturbance that passes under
the wheels on both sides of the vehicle
[0130] In the embodiments depicted in FIGS. 20 and 22 wheel
supports on a given side of the vehicle (same-side wheel supports)
include one or more springs that couple the forward wheel support
to the aft wheel support. In these embodiments, the motion of a
same-side wheel support thereby depends, at least partly, on the
motion of the other same-side wheel support. However, the present
invention also includes embodiments such as the one depicted in
FIG. 21, in which the motion of each wheel support is substantially
independent of the motion of each other wheel support.
[0131] In some embodiments of the present invention, the extent of
stagger between opposite side wheels is as great as half the
distance between rotational axes of same-side wheels. However, the
present invention also includes those embodiments in which the
extent of stagger is less.
[0132] In the embodiments depicted in FIGS. 20-22, an even total
number of rotational axes are arranged on both sides of the vehicle
in an alternating longitudinal pattern, with no rotational axis
being coincident with any other rotational axis. However, those of
ordinary skill in the art will recognize that the present invention
contemplates not only embodiments in which there is a forward-most
wheel on the right side of the vehicle with an aft-most wheel on
the left side, but also embodiments in which the forward-most wheel
is located on the left side and the aft-most wheel is located on
the right side. Further, the present invention also contemplates
those embodiments in which both the forward-most and aft-most
wheels are on the same side of the vehicle, and also those
embodiments in which one side of the vehicle has an even number of
wheels and the other side of the vehicle has an odd number of
wheels, such as by way of example, a vehicle with two wheels on one
side and one wheel on the other side. Further, the total number of
rotational axes per frame section is as low as two, and is as great
as required in the particular application.
[0133] The use of element numbers the same as numbers previously
used, including element numbers with letter suffixes, indicates
that the element referred to is the same, except as described.
[0134] FIG. 20 depicts an embodiment of the present invention to
which the discussion herein relative to FIGS. 1, 2 and 3 is
applicable, except as now described. Although a description of the
"a" side components is given, those of ordinary skill in the art
will recognize applicability of the description to the "b" side
components. Frame and suspension section 398 of a vehicle frame
includes a forward-most wheel 8a and a rear-most wheel 10a located
on one side of the vehicle frame. Wheels 8a and 10a are pivotally
supported by wheel supports 24a and 26a, respectively, in a manner
as previously described. Wheel supports 24a and 26a are coupled
together by a leaf spring 70a, also in a manner as previously
described. Further, biasing members 50a, 56a and 60a are located
generally above the rotational axes of the wheels, also as
previously described.
[0135] The rotational axes 12a and 14a of wheels 8a and 10a,
respectively, are staggered, or longitudinally spaced apart, from
the rotational axes 12b and 14b of wheels 8b and 10b, respectively.
In one embodiment, the four rotational axes are arranged in an
alternating longitudinal pattern, with no rotational axis being
coincident with any other rotational axis. Rotational axis 12a is
located in this embodiment aft of rotational axis 12b, and forward
of rotational axis 14b. Rotational axis 14a is located aft of all
other rotational axes.
[0136] FIG. 21 depicts an embodiment of the present invention to
which the description herein relative to FIG. 5 and related figures
is applicable, except as now described. Although a description of
the "e" components is given, those of ordinary skill in the art
will recognize applicability of the description to the "a," "b,"
"c," "d," and "f," components. As previously described, frame and
suspension section 498 of a vehicle frame includes a wheel 102e and
tire 104e rotatably supported by a spindle 114e coupled to a wheel
support 100e. The wheel support is pivotally attached to frame
section 498 by pivotal attachments 108e and 110e. An air spring
133e biases wheel support 100e and wheel 102e to a position
intermediate of an uppermost position and a lowermost position. An
optional shock absorber 136e for dampening motion of wheel 102e is
pivotally coupled to both wheel support 100e and frame structure
416. The rotational axes 158a, 158c, and 158e, of wheels 104a,
104c, and 104e, respectively, are staggered, or longitudinally
spaced apart, from the rotational axes 158b, 158d, and 158f, of
wheels 104b, 104d, and 104f, respectively. The present invention
also contemplates patterns of stagger other than that shown in FIG.
21, for example, including an asymmetric pattern in which
rotational axis 158b is located forward of rotational axis 158a, or
in which rotational axis 158e is located aft of rotational axis
158f.
[0137] FIG. 22 depicts an embodiment of the present invention that
is the same as the embodiments described herein relative to FIGS.
14, 15 and 16, except as now described. Although a description of
the forward-most "b" components is given, those of ordinary skill
in the art will recognize applicability of the description to the
"a," "c," and "d," components. Further, although an embodiment with
a leaf spring linking adjacent, same-side wheel supports is shown,
those of ordinary skill in the art will recognize that the present
invention also includes the embodiments depicted in FIG. 16, which
include an air spring.
[0138] As shown in FIG. 22, a wheel set comprising a pair of wheels
104b' and 104b'' rotatable about an axis 158b are supported by a
wheel support 100b' pivotally attached to frame structure 516 by
pivotal attachments 108b and 110b. The pitching movement of wheel
support 100b' is dampened by shock absorber 136b, which is
pivotally coupled to both frame section 516 and wheel support
100b'. Shock absorber 136b is substantially horizontal.
[0139] The rotational axes 158b and 158d of wheels 104b' and 140d',
respectively, are staggered, or longitudinally spaced apart, from
the rotational axes 158a and 158c of wheels 104a' and 104c'. As
shown, the four rotational axes are arranged in an alternating or
longitudinally spaced apart pattern, with no rotational axis of any
one wheel set being coincident with the rotational axis of any
other wheel set. Those of ordinary skill in the art will recognize
that the present invention also contemplates those embodiments in
which only wheel sets "a, b," and "d," are present.
[0140] FIG. 23 depicts an embodiment of the present invention that
is the same as the embodiments described herein relative to FIGS.
14, 15 and 16, except as now described. The wheel support described
herein may be pivotally attached to a frame as trailing-arm wheel
supports, in which the pivotal attachment of the wheel support to
the frame is located forward of the rotational axis of the wheel,
or as leading-arm wheel supports, in which the pivotal attachment
of the wheel support to the frame is located rearward of the
rotational axis of the wheel.
[0141] As seen in FIG. 23, a first wheel support 100'a rotatably
supporting a wheel 104a on a first side of frame 516 has inboard
pivotal attachment 108 and outboard pivotal attachment 110 located
forward of rotational axis 158a. A spring, preferably an air spring
133a, urges first wheel support 100'a apart from a portion of frame
516. An end of air spring 133a is coupled to frame 516 below
rotational axis 158a.
[0142] A second wheel 104b is pivotally supported by a second wheel
support 100'b on the other side of frame 516 in a manner similar to
that for the "a" components described above. However, inboard
pivotal attachment 108 and outboard pivotal attachment 110 of wheel
support 100'b are placed rearward of rotational axis 158b. By this
arrangement of a trailing arm wheel support 100'a on one side of
the frame and a leading-arm wheel support 100'b on the other side,
it is possible to use an identical wheel support for opposing sides
of the vehicle, and thus benefit from a reduction in cost of the
frame and suspension section 698, and also a reduction in the
number of different parts for building a frame and suspension
section 698.
[0143] The present invention also contemplates those embodiments in
which other combinations of leading and trailing wheel supports are
utilized on a frame and suspension section. Wheels 104a and 104c
are shown supported by wheel supports 100'a and 100'c,
respectively, both wheel supports being pivotally supported by a
common portion of frame 616. Other embodiments of the present
invention include wheel supports arranged as shown in FIG. 23 with
wheels 104b and 104d. Those wheels, supported by wheel supports
100'b and 100'd, respectively, may be placed close together by
arranging the pivot axes of the respective wheel supports as shown.
Those of ordinary skill in the art will recognize that frame and
suspension section 698 as shown in FIG. 23 is but one arrangement
combining leading and trailing wheel supports, and that many other
arrangements are contemplated by the present invention.
[0144] The inventions described in my other patent applications,
namely U.S. patent application Ser. No. 09/318,428, filed May 25,
1999 and entitled AXLELESS VEHICLE SUSPENSION SYSTEM; U.S. patent
application Ser. No. 09/654,584, filed Sep. 1, 2000, and entitled
STAGGERED INDEPENDENT SUSPENSION; U.S. Provisional Patent
Application Ser. No. 60/202,237, filed May 5, 2000, and entitled
ELECTRIC CAR SUSPENSION; and U.S. Provisional Patent Application
60/222,478 filed Aug. 2, 2000 and entitled SINGLE ARM VEHICLE
SUSPENSION; are incorporated herein by reference.
[0145] In another embodiment, the present invention relates to a
low profile chassis section for the center and rear portion of a
vehicle. The chassis section includes a low profile suspension
system that supports the rear wheels with independent trailing arm
wheel supports. Preferably, the trailing arm wheel support has a
pivot axis below the rotational axis of the wheels. The chassis
includes a frame section having a substantially planar top surface.
Trailing arm wheel supports according to the present invention
permit the top surface of the frame section to be located below the
rotational axes of the rear wheels. Preferably, the rear wheels are
not powered by the engine of the vehicle, and are not steerable.
Preferably, the rear wheels are constrained to pitching motion
describable with a single degree of freedom.
[0146] A chassis section according to the present invention
preferably is rigidly coupled to a cab section having a high
profile sub-frame and floor. The cab section preferably includes
steerable front wheels, an engine to drive the front wheels, and a
driver's seat and controls. In one embodiment of the present
invention the cab section is separated from an existing vehicle
which typically includes a high profile frame throughout the length
of the existing vehicle. The center and rear portion of the high
profile frame section of the existing vehicle is separated from the
cab section, and the low profile chassis section according to an
embodiment of the present invention is rigidly coupled to the high
profile cab section, resulting in a new vehicle.
[0147] A separate payload section, such as an ambulance
compartment, passenger compartment, or cargo compartment can be
coupled to the top of the center and rear chassis section and also
to the rear of the cab section. The payload compartment can have a
floor that is close to the roadway by placement of the top surface
of the underlying chassis section below the rotational axes of the
rear wheels, in the case of an ambulance compartment, having a low
floor permits easier entrance and exit from the compartment as
compared to a standard ambulance with a high profile floor. A low
profile chassis according to the present invention permits easier
movement of wheelchairs and gurneys into and out of the ambulance
compartment. As another example, a payload compartment for carrying
passengers around airports and hotels can have a low profile floor
which makes ingress and egress easier for elderly and handicapped
passengers. As another example, a payload compartment comprising a
low profile floor cargo compartment such as for a short haul
delivery truck permits the delivery person to bring cargo into and
out of the compartment with less fatigue. A payload compartment
attached to a chassis according to the present invention can also
have a lower overall height than an existing vehicle with high
profile chassis, yet have a useful interior height from floor to
ceiling that is about the same as for an existing vehicle.
Therefore the present invention permits the use of a payload
compartment with a large interior that can pass underneath a low
hanging obstruction, such as those found at the arrival and
departure areas of some hotels.
[0148] In one embodiment of the present invention, the chassis
section is fastened by bolts or other fasteners to a sub-frame of
the cab section. Fastening is useful where the members of the cab
sub-frame are heat treated, in which cases welding the chassis to
the cab subframe lessens the material properties of the
subframe.
[0149] Referring to FIGS. 24-29, vehicle chassis 1020 according to
one embodiment of the present invention includes a substantially
planar forward frame portion 1040, a substantially planar rearward
frame portion 1060, and an intermediate frame portion 1050 located
therebetween. Chassis 1020 further includes a support section 1150
located forward of forward frame portion 1040, section 1150 bolting
to a front sub-frame 1220 supporting a front suspension/engine
module 1230. Forward frame 1040, intermediate frame 1050, and
rearward frame 1060 are preferably of the ladder-type, each
comprising a plurality of lateral structural members 1070,
longitudinal structural members 1072, and/or diagonal structural
members 1074. The various structural members 1070, 1072, and 1074
are preferably welded together into a ladder-type or box structure
such that the top surfaces of the structural members define a
substantially planar top surface 1022 that extends generally across
frame sections 1040, 1050, and 1060 (as best seen in FIG. 25c).
Chassis 1020 preferably includes hollow structural members 1042 and
1062 which run in a generally longitudinal direction. Structural
members 1042 and 1062 provide housing and protection for an exhaust
pipe 1053 carried therein.
[0150] Although a ladder-type or box structure has been shown and
described, the present invention also contemplates other
configurations of frame structure, with the top surface of the
frame portions being generally located below the rotational axes of
the rear wheels. A separable vehicle body or payload portion 1300
including an interior with a floor 1302 and exterior body panels
attaches to frames section 1040, 1050, and 1060, preferably by
bolting or use of other fasteners, including riveting, or by
welding or other attachment methods.
[0151] Intermediate frame 1050 preferably includes a substantially
planar center frame section 1054 and left and right wheel housings
1100 and 1101, respectively, on either side of section 1054. Left
and right rear wheels 1130 and 1131 for the vehicle are located
within their respective wheel housings. A left wheel 1130 is
pivotally supported from intermediate section 1050 by a wheel
support 100'' which pivotally couples to a forward portion 1120 of
intermediate frame portion 1040 by inboard and outboard pivot
joints 108 and 110, respectively. The pivotal attachment of the
wheel support to the frame permits pivoting motion of the supported
wheel in a pitching direction only, and constrains the wheel
against yawing motion such as the type necessary for steering
control. Although what has been shown and described is a wheel
support 100'' pivotally coupled to intermediate section 1050, the
various embodiments of the present invention shown and described
herein contemplate use of any of the various wheel supports shown
and described herein.
[0152] In one embodiment, a spring 133 such as an inflatable air
spring is placed between a portion of the wheel support and the
bottom side of spring support member 1140. The spring provides
resilient support of the vehicle from the roadway, the spring
urging apart the frame from the wheel support. Spring support 1140
has a top surface within frame section 1054 that is at or below
plane 1022. Although what has been shown and described pertains to
the left wheel, it is understood that there is preferably a mirror
image wheel support supporting the vehicle from a right wheel 1131
located within wheel housing 1101, right wheel 1131 being pivotally
supported from portion 1121 of frame 1050.
[0153] In one embodiment of the present invention, the wheel
supports are trailing arm supports, such that the pivot axes 109
and 111 of the wheel supports 100'' are forward of the rotational
axes 158 of the wheels 1130 and 1131. Further, as can be best seen
in FIG. 29, rotational axes of the wheels are located above plane
1022. Preferably, a wheel support according to the present
invention supports a stub axle 114, and stub axle 114 supports one
or more wheels from a single side in cantilever fashion such that
the wheel is located outboard of the wheel support, leaving the
space inboard of the wheel and stub axle for the wheel support,
spring, and cargo compartments. Further, pivot joints 108 and 110
which pivotally couple the wheel support to the frame are located
inboard of the supported wheel. Preferably, the pivot axes 109 and
111 of the wheel support are parallel to the rotational axis of the
supported wheel, but the present invention also contemplates a
wheel support pivotable about an axis that is not perpendicular to
the longitudinal centerline of the vehicle and not parallel to the
rotational axis of the supported wheel. The present invention also
contemplates suspension systems located generally within the wheel
housings, such as the type shown in my issued patents referenced
above and incorporated herein by reference.
[0154] A support section 1150 is preferably coupled to sub-frame
1220 which supports front suspension and engine module 1230 located
in front of forward frame 1040. Support section 1150 includes a
pair of support members 1160 and 1161 which are cantilevered from
the forward portion of forward frame 1040 and which are further
supported by a pair of lateral braces 1162 and 1163. Support arms
1160 and 1161 preferably include a plurality of holes 1170.
Sub-frame 1220 and other structural components which support the
front suspension and engine module 1230 are rigidly coupled to
frame portion 1150 by the use of fasteners 1171 in conjunction with
holes 1170. In one embodiment of the present invention the
sub-frame supporting the engine and front suspension is cut away
from or otherwise removed from an existing vehicle. The frame
portion of the existing vehicle aft of the cab section is
discarded, and the sub-frame of the cab section is bolted to
chassis 1020.
[0155] Sub-frame 1220 of cab section 1200 provides "high profile"
support of at least one of the engine or front suspension of cab
section 1200. Typically, the structural members of sub-frame 1220
are above rotational axis 1206 of front wheel 1204. The floor 1222
of cab section 1200 is also located above the rotational axis 1206.
As can be seen in FIG. 29, a vehicle 1400 according to one
embodiment of the present invention includes a top surface 1221 of
the frame of the cab section that is above rotational axes 1206 and
158 of wheels 1206 and 1130, respectively, and a top surface 1022
of the frame supporting the payload section 1300 that is below
rotational axes 1206 and 158. The combined frame for vehicle 1400
includes a forward-most sub-frame 1220 with a top surface that is
at a first elevation above the rotational axes of the wheels, and a
center and rear-most frame section 1020 with a top surface that is
at a second elevation below the rotational axes of the wheels.
[0156] Although what has been shown and described is a support
section that couples the front frame section to the sub-frame of
the cab section, the present invention also contemplates those
embodiments in which portions of the sub-frame and vehicle chassis
section are unitary. For example, the present invention
contemplates those embodiments in which the one or more central
longitudinal frame member of the rear vehicle chassis are
integrally formed with longitudinal frame members of the sub-frame.
In another embodiment, one or more frame members of the rear
vehicle chassis are welded to one of more frame members of the
sub-frame, and the welded assembly is heat treated as a unitary
assembly.
[0157] FIGS. 27 and 28 are photographs of a chassis coupled to a
cab section according to another embodiment of the present
invention. FIG. 29 is a partly sectional and partly side schematic
representation of a cab section coupled to a chassis which supports
a payload section according to another embodiment of the present
invention. Vehicle chassis 1020 is shown coupled to a cab section
1200. Cab section 1200 includes an engine and a pair of front
wheels 1204 and 1205 which are both steerable and which both apply
the power provided by the engine to the roadway. Cab section 1200
includes a driver's seat 1210, windshield 1215, and other features
necessary for the powering and control of the vehicle. Cab section
1200 includes a cab floor 1222 that is at an elevation above the
rotational axes of the front and rear wheels, and also above plane
1022 of chassis 1020 and floor 1302 of payload compartment 1300. In
the embodiment depicted in FIGS. 27 and 28 a passenger compartment,
cargo compartment, ambulance section, or other payload section 1300
can be attached above chassis section 1020 and behind cab section
1200. FIG. 29 schematically shows a payload section 1300 attached
to a chassis section 1020. FIG. 29 also shows cab section 1200 in
part sectional view, with the front suspension and engine module
1230 visible, and being supported by sub-frame 1220.
[0158] The use of two thousand prefixes (2XXX) or three thousand
prefixes (3XXX) designate the same element as the one thousand
prefix (1XXX) previously described except as shown and described
differently.
[0159] FIGS. 30, 31, and 32 depict top plan, rear and side
elevational view of an apparatus 2021 including a vehicle chassis
2020 coupled to a simplified cab section 2200. Cab section 2200 is
shown with a front suspension and engine module 2230, a front axle
2208, left and right wheels 2204 and 2205, respectively, and left
and right brake assemblies 2207a and 2207b, respectively. These
features of cab 2200 are shown schematically. Other features of cab
section 2200 have been removed for sake of clarity.
[0160] Referring to FIGS. 30-33, vehicle chassis 2020 according to
one embodiment of the present invention includes a substantially
planar forward frame portion 2040, a substantially planar rearward
frame portion 2060, and an intermediate frame portion 2050 located
therebetween, and also between wheel housings 2100 and 2101.
Chassis 2020 further includes a support section 2150 located
forward of forward frame portion 2040, section 2150 bolting to a
front sub-frame 2220 supporting a front suspension/engine module
2230.
[0161] Forward frame 2040, intermediate frame 2050, and rearward
frame 2060 are preferably of the ladder-type, each comprising a
plurality of lateral structural members 2070, longitudinal
structural members 2072, and/or diagonal structural members 2074.
The various structural members 2070, 2072, and 2074 are preferably
welded together into a ladder-type or box structure such that the
top surfaces of the structural members define a substantially
planar top surface 2022 that extends generally across frame
sections 2040, 2050, and 2060 (as best seen in FIGS. 31 and
32).
[0162] Forward frame portion 2040 includes a plurality of lateral
structural members 2070a that extend transversely from the outboard
surface of one of the central longitudinal members 2042a or 2042b
to the inboard surface of the adjacent outboard longitudinal member
2072a or 2072b, respectively. As best seen in plan view 30, forward
frame portion 2040 resembles a pair of "ladder-type" structures
that extend from either side of the central "backbones" 2042a and
2042b. In one embodiment, frame members 2041, 2042a, 2042b, 2072a
and 2072b have closed-off, rectangular cross-sections. Preferably,
transverse structural members 2072a have an "I" or "H"
cross-sectional shape. However, the present invention further
contemplates various types of common cross-section structural
members.
[0163] Chassis 2020 preferably includes a pair of hollow structural
members 2042a and 2042b which run in a generally longitudinal
direction from forward-most transverse beam 2041 to aftmost
transverse beam 2072e. Structural members 2042a and 2042b provide
protection for an exhaust pipe 2053 carried therebetween. As best
seen in FIG. 30, exhaust pipe 2053 begins at the forwardmost end of
forward frame portion 2040, passing through a hole within
transverse beam 2041. Exhaust pipe 2053 extends fore to aft down
the longitudinal centerline of chassis section 2020, to a point
just aft of intermediate frame portion 2050. Exhaust pipe 2053 has
a diameter which is less than the height of central structural
members 2042a and 2042b. Exhaust pipe 2053 is located below the top
surface of members 2042a and 2042b, and above the bottom surface of
members 2042a and 2042b. By being nested between members 2042a and
2042b, exhaust pipe 2053 is protected from many types of debris and
irregularities on the road surface.
[0164] Pipe 2053 has a round cross section in portion 2053a which
extends through front frame portion 2040 and a portion of
intermediate frame portion 2054. This circular cross section
changes to an oval cross section within portion 2053b, which begins
within intermediate frame portion 2054 and extends a short distance
into rear frame portion 2060. Exhaust pipe 2053b includes a right
angle section, such that the exhaust exits at a location aft of
wheel housing 2100.
[0165] Intermediate frame 2050 preferably includes a substantially
planar center frame section 2054 and left and right wheel housings
2100 and 2101, respectively, on either side of section 2054. Left
and right rear wheels 2130 and 2131 for the vehicle are located
within their respective wheel housings. Although what has been
shown and described are various chassis sections that include wheel
housings, the present invention also contemplates those embodiments
in which the wheel housings are not part of the chassis, but are
integrated into the separable vehicle body or payload portion which
is supported by the chassis.
[0166] A left wheel 2130 is pivotally supported from intermediate
section 2050 by a wheel support 100'' which pivotally couples to a
forward portion 2120 of intermediate frame portion 2040 by inboard
and outboard pivot joints 108 and 110, respectively, in a manner as
previously described herein. The pivotal attachment of the wheel
support to the frame permits pivoting motion of the supported wheel
in a pitching direction, and preferably constrains the wheel
against yawing motion such as the type necessary for steering
control. The various embodiments of the present invention shown and
described herein contemplate use of any of the various wheel
supports shown and described herein.
[0167] In one embodiment, a spring 133 such as an inflatable air
spring is placed between a portion of the wheel support and the
bottom side of spring support member 2140, in a manner as
previously described herein. The spring provides resilient support
of the vehicle from the road surface, the spring urging apart the
frame from the wheel support. Spring support 2140 has a top surface
within frame section 2054 that is at or below plane 2022. Although
what has been shown and described pertains to the left wheel, it is
understood that there is preferably a mirror image wheel support
supporting the vehicle from a right wheel 2131 located within wheel
housing 2101, right wheel 2131 being pivotally supported from
portion 2121 of frame 2050.
[0168] In one embodiment of the present invention, the wheel
supports are trailing arm supports, such that the pivot axes 109
and 111 of the wheel supports 100'' are forward of the rotational
axes 158 of the wheels 2130 and 2131. Further, as can be best seen
in FIGS. 31 and 32, the rotational axes of the wheels are located
above plane 2022. Preferably, a wheel support according to the
present invention supports a stub axle 114, and stub axle 114
supports one or more wheels from a single side in cantilever
fashion such that the wheel is located outboard of the wheel
support, leaving the space inboard of the wheel and stub axle for
the wheel support, spring, and cargo compartments. Further, pivot
joints 108, 109, 110 and 111 which pivotally couple the wheel
supports to the frame, are located inboard of the supported wheel.
Preferably, the pivot axes of the wheel supports are parallel to
the rotational axis of the supported wheel, but the present
invention also contemplates a wheel support pivotable about an axis
that is not perpendicular to the longitudinal centerline of the
vehicle and not parallel to the rotational axis of the supported
wheel. The present invention also contemplates suspension systems
located generally within the wheel housings, such as the type shown
in my issued patents referenced above and incorporated herein by
reference.
[0169] Rearward frame portion 2060 extends aft from wheel housings
2100 and 2101, and supports the aftmost part of a separable vehicle
body or payload portion. Forward longitudinal frame members 2042a
and 2042b terminate just aft of intermediate frame section 2050,
where each frame member is welded to an aft longitudinal frame
member 2062a and 2062b, respectively. These aft longitudinal frame
members extend through rear portion 2060, and are welded to rear
transverse member 2072e. A pair of outboard longitudinal members
2072c and 2072d interconnect wheel housings 2100 and 2101,
respectively, to aft transverse member 2072e. A plurality of
interconnecting transverse members 2070b are welded at one end to
outboard longitudinal members 2072c or 2072d, and at the other end
to central longitudinal members 2062a or 2062b, respectively.
[0170] In a preferred embodiment, chassis section 2020 has a
substantially planar top surface which extends throughout frame
sections 2040, 2050, and 2060. For example, the top surfaces of
forward and intermediate members 2042a, 2042b, 2072a, 2072b, 2070a,
2120, 2140, and 2141 are preferably located in a single plane 2022
which is lower than rotational axes 158 of the rear wheels, as best
seen in FIG. 31. The top surfaces of aft members 2062a, 2062b,
2070b, 2072c, 2072d, and 2072e are preferably also located in a
plane 2022. However, in one embodiment of the present invention,
the lower surfaces of these same members are preferably arranged
such that the bottom surfaces of the aft members have increased
clearance from the road surface. The bottom surface of the forward
and intermediate members are closer to the road surface, thus
allowing the forward and intermediate sections to include channel
sections with a greater vertical height and thus stronger
cross-sectional properties.
[0171] Referring to FIGS. 30 and 32, the bottom surfaces of forward
and intermediate members 2042a, 2042b, 2072a, 2072b, 2070a, 2120,
2140, and 2141 are preferable located in a single lower plane
2022b. Further, the bottom surfaces of aft members 2062a, 2062b,
2070b, 2072c, 2072d, and 2072e are preferably located in a single
plane 2022c that is elevated more above the road surface than plane
2022b. Preferably, plane 2022c including the bottom surfaces of the
aft members is spaced apart and parallel to plane 2022 containing
the top surfaces of the same aft members (refer to FIG. 32).
Similarly, the bottom surfaces of the forward and intermediate
members located in plane 2022b are spaced apart and parallel to
plane 2022 containing the top surfaces of the same forward and
intermediate members.
[0172] Thus, chassis 2220 includes a forward section with a
preferably planar body surface 2022b spaced apart from top planar
surface 2022 by a first amount, and a bottom planar surface 2022c
which is spaced apart from top surface 2022 by a second amount.
Preferably the second amount is less than the first amount, thereby
giving increased ground clearance to the aft portion 2060 of the
chassis. This increased ground clearance makes it less likely that
a road vehicle incorporating this embodiment of the present
invention will strike or rub against the road surface when the road
vehicle begins to climb an elevated road surface. In one
embodiment, the distance between top plane 2022 to bottom plane
2022b is about 4-6 inches, and top plane 2022 is about 10-12 inches
from the road surface. However, the present invention also
contemplates those embodiments in which the top surfaces of
structural members 2042a, 2042b, 2070a, 2072a, and 2072b do not lie
in a common top plane, but are all beneath the rotational axes of
the rear wheels.
[0173] In one embodiment of the present invention, forward frame
portion 2040 includes unique provisions for incorporating a ramp to
facilitate wheelchair access to a payload portion of the road
vehicle. As best seen in FIGS. 32 and 33, frame portion 2040
defines a recessed pocket 2180 on one side of forward frame portion
2040. Recessed pocket 2180 includes a bottom boundary established
by the top surface of structural members 2071a, 2071b, and 2071c.
These three members transition on a downward angle from an inboard
portion of frame section 2040, such as from the outboard surface of
central longitudinal member 2042b. The other end of members 2071a,
2071b, and 2071c are attached to an outboard portion of frame 2040,
such as outboard longitudinal member 2073.
[0174] As best seen in FIG. 33, longitudinal member 2073 has a
vertical height which is less from that of adjacent longitudinal
member 2072b. This cutaway portion along the outboard side of
chassis 2020 presents a lower height for those passengers boarding
on wheel chairs. In one embodiment of the present invention, the
bottom boundary of recessed pocket 2180 is inclined more than about
11.5 degrees and less than about 17.5 degrees, as indicated by
angle 2181 of FIG. 34. More preferably, angle 2181 is more than
about 14 degrees and less than about 15 degrees. This angle is
chosen so that the subsequent vertical rise of the bottom boundary,
as would be experienced by a person in a wheelchair entering the
vehicle, is about 1 inch for every 4 inches of lateral travel.
[0175] In another embodiment of the present invention, the bottom
surface 2022b of frame portion 2040 is established to facilitate
use of recessed pocket 2180 as part of a wheelchair ramp. In this
embodiment, bottom surface 2022b is about 6.5 inches from the road
surface. Using the previously mentioned ratio of a 4:1 declining
angle, a ramp pivotably hinged to longitudinal member 2073 would
have to be about 25-27 inches long. By maintaining the bottom
surface of the chassis close to the road surface, it is possible to
incorporate a ramp of moderate length, which can be hinged from
beam 2073. When not in use, the ramp can be stored inside the
vehicle, being supported on the top of beams 2071a, 2071b and
2071c. When in use, the ramp can be folded out to extend from the
edge of beam 2073 to the ground. Thus by being low to the ground,
it is possible to incorporate a folding wheelchair ramp for ingress
and egress of disabled passengers. The weight, complexity and cost
of a lifting device is not required.
[0176] A support section 2150 is preferably coupled to sub-frame
2220 which supports front suspension and engine module 2230 located
in front of forward frame 2040. Support section 2150 includes a
pair of support members welded 2160 and 2161 which are cantilevered
from the forward transverse beam 2041. Support arms 2160 and 2161
preferably include a plurality of holes 2170. Sub-frame 2220 and
other structural components which support the front suspension and
engine module 2230 are rigidly coupled to support section 2150 by
the use of fasteners 2171 in conjunction with holes 2170.
[0177] In some embodiments of the present invention, some portions
of sub-frame 2220 are heat treated for improved strength. In these
embodiments, the use of fasteners such as bolts, rivets, and
related fasteners obviates the need to weld a portion of chassis
2020 to sub-frame 2220. Welding of a sub-frame 2220 that has been
heat treated could result in an undesirable change to the heat
treated properties. Therefore, some embodiments of the present
invention include joining of a chassis to a sub-frame by methods
that do not use sufficient heat to change the heat treated
properties. However, the present invention also contemplates those
embodiments in which there is a negligible or acceptable affect of
welding support section 2150 to forward frame portion 2040.
[0178] In one embodiment of the present invention the sub-frame
supporting the engine and front suspension is cut away from or
otherwise removed from an existing vehicle. The rear frame portion
of the existing vehicle aft of the cab section is not used, and the
sub-frame of the cab section is bolted to chassis 2020. In other
embodiments of the present invention, the sub-frame, engine and
front suspension unit, and other forward portions of the vehicle
are taken from several different existing vehicles, or fabricated
specifically for use with chassis section 2020.
[0179] Sub-frame 2220 of cab section 2200 provides "high profile"
support of at least one of the engine or front suspension of cab
section 2200. In some embodiments, the structural members of
sub-frame 2220 are above rotational axis 2206 of front wheel 2204.
The floor of cab section 2200 is also located above the rotational
axis 2206. A vehicle 2400 according to one embodiment of the
present invention includes a top surface of the frame of the cab
section that is above rotational axes 2206 and 158 of wheels 2206
and 2130, respectively, and a top surface 2022 of the frame
supporting the payload section that is below rotational axes 2206
and 158. The combined frame for a vehicle includes a forward-most
sub-frame 2220 with a top surface that is at a first elevation
above the rotational axes of the wheels, and a center and rear-most
frame section 2020 with a top surface that is at a second elevation
below the rotational axes of the wheels.
[0180] What follows now are specific dimensions for a particular
embodiment of the present invention which is related to apparatus
2021 of FIGS. 30, 31, 32, and 33. However, it is understood that
these particular dimensions are provided as examples only and are
not limiting.
[0181] In a specific embodiment, the height of plane 2022 above the
road surface is from 10-12 inches and preferably about 11 inches.
The distance from the road surface to underneath planar surface
2022b is 5-8 inches and preferably about 6.5 inches. The distance
form the road surface to planar surface 2022c on aft frame portion
2060 is 7-10 inches and preferably about 8 inches.
[0182] The vertical height of frame portions 2042a, 2042b, 2072a,
2072b, and 2070a is 4-6 inches, and preferably about 5 inches. The
width of these same beams is preferably from 2-3 inches. The
vertical height of beams 2070b, 2072c, 2072d, 2072e, 2062a, and
2062b, is preferably from about 2-4 inches and most preferably
about 3 inches. The vertical height of front transverse beam 2041
is preferably from about 7-9 inches and most preferably about 8
inches. The width of beam 2041 ranges from about 1-3 inches and
preferably about 2 inches.
[0183] The lateral width of pocket 2180 from the outboard edge of
the pocket along the outer surface of beam 2073 to the inboard edge
of the pocket along the outboard surface of beam 2042b is from
about 38-42 inches and preferably about 40 inches. The width of
pocket 2180 from the inner surface of beam 2141 to the front face
of beam 2072b is from about 33-37 inches and most preferably about
35 inches. The vertical distance from plane 2022 to the top surface
of beam 2073 is from about 3-5 inches and preferably about 4
inches. The distance from the longitudinal centerline of the
chassis to the outboard edge of beam 2072b is from about 45-50
inches and preferably about 47.5 inches. Beams 2041, 2072a, 2072b,
2072c, 2072d, 2072e, 2042a, 2042b, 2062a, and 2062b are preferably
of a closed channel construction with a rectangular cross section.
Beams 2070a and 2070b are preferably of an open channel
construction with a "c" cross section, or I-beams.
[0184] FIG. 34 shows a side elevational view of another embodiment
of the present invention. FIG. 35 shows an apparatus 2021' which
includes a chassis section 2020 as previously described, and a
modified cab section 2200'. The use of a prime (') mark by an
element number indicates an element substantially similar to the
non-prime element, except for those differences which are shown or
described.
[0185] Cab section 2200' includes a subframe 2220' and a front
suspension and engine module 2230' that have been modified to
permit a lowering of the driver's seat and floor of the cab
compartment. Front suspension and engine module 2230' includes an
engine 2232' and transmission 2234' located aft and lower than the
location shown and described for engine 2232 and transmission 2234.
Engine 2232 is located over the centerline 2206 of wheel 2205, as
best seen in FIG. 32. The rotational centerline and power takeoff
for engine 2232 is above the axis of the front wheels, and must be
brought to the lower level of front axle 2208 by a transfer case
2236. The rotational centerline of the engine and transmission, as
well as the various housings of the engine and transmission,
generally establish lower boundaries for the floor of the cab
section. Therefore, apparatus 2020 can include one or more steps
which the driver uses to climb from road level to the driver's
seat. Climbing a large distance is undesirable in some
applications, such as for delivery trucks which make frequent
starts and stops. In these situations, the height and number of
steps that must be climbed leads to increased injuries and problems
for the delivery drivers.
[0186] Apparatus 2021', shown in FIG. 34, includes a mounting
arrangement for the engine 2232' and transmission 2234' that
reduces the height of the floor of cab section 2200'. Front
suspension and engine module 2230' includes an engine 2232' placed
aft of front axle 2208'. Engine 2232' is also rotated 180 degrees
so that its power takeoff is toward the front of apparatus 2021'.
Transmission 2234' is located between engine 2232' and front axle
2208'. The centerline 2232a' of the engine is preferably co-planar
with axis 2206' of the front axle. Apparatus 2021' does not need a
transfer case because the centerline of the engine is close to, or
intersects the centerline of the front axle. The present invention
also contemplates those embodiments in which the power input of the
front axle is offset slightly from the rotational centerline of the
axle. Therefore, the height of the floor of cab section 2200' is
lower, and fewer steps are required for entry of the driver from
the road surface.
[0187] FIG. 35 is a top plan view of an apparatus according to
another embodiment of the present invention. A vehicle chassis 3020
is similar to inventive chassis 1020 and 2020 as previously
described, but with the following differences. Chassis 3020
includes three central longitudinal members 3042a, 3042b, and
3042c, that traverse the length of forward frame section 3040.
Three longitudinal frame members 3062a, 3062b, and 3062c, traverse
the length of rear frame portion 3060. Intermediate frame portion
3050 in between the forward and aft frame portions supports a
plurality of rear wheels on each side of the chassis. The left side
of chassis 20 includes forward and rear wheels 3130a and 3130b,
respectively, housed under a common wheel housing 3100. The right
side of chassis 3020 includes forward and rear wheels 3131a and
3131b, respectively, housed under a common wheel housing 3101.
Further, chassis 3020 includes upper spring supports 3140a and
3140b which are in contact with the top surface of the springs held
by the wheel supports (not shown). Further, chassis 3020 includes
upper spring supports 3141a and 3141b which are in contact with the
top surface of the springs held by the wheel supports (not
shown).
[0188] FIG. 37 shows a front, left, top true perspective view of
chassis section 2020 coupled to a portion of a cab section 2200.
Various portions of cab 2200, such as the body, seats, windshield,
and other features have been removed for sake of clarity. Cab
section 2200 includes a subframe 2220 which supports a front
suspension and engine module 2230. Module 2230 includes a front
axle 2208 which provides power to driven front wheels 2204 and
2205. Wheels 2204 and 2205 rotate about a common centerline 2206
which, in one embodiment of the present invention, is located below
engine rotational axis 2232a. Power is provided to the driven front
wheels by a transfer case 2236, which in turn receives power from a
transmission 2234 coupled to engine 2232.
[0189] Subframe 2220 includes a pair of longitudinally extending
front frame members 2240 and 2241, located on the left and right
sides, respectively, of subframe 2220. Each side of front axle 2208
is pivotally coupled to a respective frame member 2240 and 2241 by
trailing arm supports 2242 and 2243, respectively. Each trailing
arm support is pivotally coupled to the frame member by a single
degree of freedom pivot joint. For example, trailing arm support
2242 is coupled to frame member 2240 by a pivot joint 2244a located
within a housing 2244b. Likewise, trailing arm support 2243 is
coupled to frame member 2241 by a pivot joint 2245a located within
a housing 2245b. In the description that follows, reference will be
made to the trailing arm support and other features of the left
side of cab section 2200, it being understood that identical and/or
mirror-image features are used on the right side, except as
noted.
[0190] FIGS. 38, 39, and 40 are enlarged views of the various
components in the vicinity of trailing arms support 2242 from side,
top, and rear viewpoints, respectively. FIG. 38 shows trailing arm
support 2242 pivotally coupled to longitudinal frame member 2240 by
a pivot joint 2244a attached within a joint housing 2244b. Pivot
assembly 2244a permits rotation of trailing arm support 2242 about
a pivot axis 2244c which is generally parallel to the rotational
axis 2206 of front axle 2208. Pivot assembly 2244a includes a
stationary member, preferably bolted to housing 2244b, and a
pivoting inner member which is attached to the forward-most end of
arm 2242.
[0191] In one embodiment, the inner pivoting member of assembly
2244a includes an inner molded elastomeric collar which is
integrally molded within the stationary member of pivot assembly
2244a. Preferably, the inner surface of the joint stationary member
includes a plurality of grooves, such that during molding of the
elastomeric collar, complimentary shaped ribs are molded into the
elastomeric material.
[0192] Referring to FIGS. 38, 39 and 40, trailing arm support 2242
extends aft from pivot joint 2244a preferably underneath front axle
2208, with the aftmost end of support 2242 being coupled to the
bottom side of an air spring 2248. The top side of air spring 2248
is in contact with static members which are rigidly attached to
front longitudinal frame member 2240. Air spring 2248 is
pressurized with a gas such as air, and urges apart the aftmost end
of arm 2242 from frame member 2240. Although what has been shown
and described is an air spring, the present invention also
contemplates the use of other biasing members, including for
example, coil springs and leaf springs.
[0193] Arm 2242 is coupled to the left side of front axle 2208,
such as by a plurality of U-bolts, as shown. In a preferred
embodiment, the support of front axle 2208 by trailing arm support
2242 occurs at a longitudinal position in between pivot joint 2244a
and air spring 2248. However, the present invention contemplates
those embodiments in which the support of the front axle by the
trailing arm support occurs at a longitudinal position aft of both
the pivot joint and the air spring.
[0194] Referring to FIG. 40, front axle assembly 2208 includes a
power input coupling 2208a. This power input coupling rotates about
an input axis 2208b, which is largely perpendicular to the central
axis 2206 of the front axle and front driven wheels. However, the
present invention also contemplates those embodiments in which the
axis of power input is displaced vertically up or down from wheel
axis 2206, as is common in some front axles.
[0195] As best seen in FIG. 37, front suspension module 2230
includes a pivotal member 2260 that pivotally couples trailing arm
2243 to longitudinal frame member 2240. Rod 2260, sometimes
referred to as a panhard rod, is pivotally coupled at one end by a
pivot joint 2260a supported within a pivot housing 2260b, the
latter being rigidly attached to trailing arm support 2243. Pivot
joint 2260a permits pivoting movement of one end of rod 2260 about
a pivot axis that is generally perpendicular to pivot axes 2244c
and 2243c of trailing arm supports 2242 and 2243, respectively.
[0196] Referring to FIG. 37, pivotal member 2260 extends laterally
from its pivotal attachment to trailing arm 2243 toward the
longitudinal centerline of engine and suspension module 2220, and
then transitions vertically up toward longitudinal frame member
2240. As best seen in FIG. 39, member 2260 is pivotally connected
by a pivot joint 2260c supported by a pivot joint housing 2260d
rigidly attached to an inboard surface of frame member 2240. Pivot
joint 2240c permits pivoting of the second end of member 2260 about
a pivot axis that is perpendicular to the pivot axes of trailing
arms 2243 and 2242, and generally parallel to the pivot axis of the
other end of member 2260.
[0197] FIGS. 41-43 depict a substantially cast wheel support 100'''
according to another embodiment of the present invention. Element
numbers designated with three prime marks (''') designate elements
that are the same as the non-prime, single prime, or double prime
elements, except as described and depicted differently.
[0198] Wheel support 100''' includes a horizontal portion 168'''
cast integrally with an upright portion 112'''. A spring support
156''' within horizontal portion 168''' receives loads from a
spring, and is reinforced by a plurality of cast stiffening ribs
169a'''. Spring support 156''' preferably includes two mounting
holes 174''' placed laterally and generally parallel to the
rotational axis of the wheel. For the configurations of wheel
supports shown herein, it is possible to dispense with a form bolt
pattern for attachment of the airspring, since the pitching-type
movement of the wheel support reduces loads on the airspring which
act to cause the airspring to move fore and aft. Therefore, a
simplified, two bolt lateral pattern is sufficient in some
embodiments to prevent side to side motion of the airspring. By
simplifying the attachment pattern from four fasteners to two
fasteners, the reliability of the airspring and wheel support is
increased by lessening the number of attachment points that can
fail.
[0199] A cast reinforcing member 170''' stiffens and strengthens
wheel support 100'''. A plurality of cast stiffening ribs 169b'''
reinforces upright portion 112'''. Attachment members 178''' and
180''' are cast integrally with wheel support 100'''. Upright
portion 112''' includes mounting provisions 134''' for attachment
of a shock absorber and brake system components.
[0200] The toe-in of wheel support 100''' is adjustable by shimming
in a manner as previously described. Camber is adjustable by
incorporating slots in stationary outer members 108c''' and/or
110c''' of the pivotal attachments. The slots permit the
orientation of outer member 108c''' or 110c''' to be adjusted
relative to a cross-member of the frame. This orientation is
maintained by a friction fit provided by fasteners 177'''.
[0201] Yet other alternate embodiments of the present invention
include a wheel support and a disc brake assembly including bleed
and pressure ports oriented to maximize the lateral extent of the
payload compartment between wheel housings. FIG. 44 is a top
perspective view, shown in partial cutaway, of a wheel 2102
rotatably supported about a stub axle 2114 which is cantilevered
from an upright portion 112''' of a wheel support 100'''. For sake
of clarity, the wheel housing, tire, and other components have been
removed. It is understood that the upright portion 112''' lies
immediately outboard of the inner surface of the vertical,
inboard-most portion of wheel housing 2100.
[0202] As shown in FIG. 44, an upright section 112''' is bolted to
a spindle 114 by fasteners through fastener attachment pattern
160'''. A rotating hub 162 is bearingly supported on spindle 114.
Coupled to hub 162 is a vented disc assembly 165 comprised of
opposing rotor plates 165a and 165b. A brake caliper assembly 2159
supported by upright portion 112''' includes two friction pads 161
which are actuated against vented disc 165 so as to slow the
vehicle. For sake of clarity, only one friction pad 161 is shown.
Those of ordinary skill in the art will recognize the applicability
of disc brakes to the many embodiments of the present
invention.
[0203] As is common in the art, brake assembly 2159 includes one or
more ports which are in fluid communication with an internal
hydraulic cylinder. For example, there can be one port which
provides flow into and out of the internal wheel cylinder, for
purposes of brake application and release, respectively. There can
be another fluid port for removal of trapped air and outward flow
of hydraulic fluid, commonly called a bleed port. For sake of
clarity, FIG. 49 is shown with a single port 2159a, which
represents either the fluid actuation port or the bleed port.
[0204] In order to get the maximum lateral distance between wheel
housings, it is necessary to place the inboard vertical walls of
the wheel housings as close to the upright portion of the wheel
supports as possible. However, other portions of the wheel, stub
axle, and brake assemblies must also be located outboard of the
inner vertical surface of upright portion 112''', so as to not
interfere with the wheel housing or, for those embodiments in which
the wheel housings are integrated into the payload section, to not
interfere with the payload section itself.
[0205] Therefore, some embodiments of the present invention utilize
a brake assembly 2159 which incorporates one or more fluid ports
that are oriented so that neither the ports, nor any equipment
attached to it, protrude inward of the innermost surface of the
brake assembly. As shown in FIG. 44, brake assembly 2159 includes a
port 2159a, preferably located on a top surface of the brake
assembly, and preferably oriented with an axis that is generally
parallel to the longitudinal axis of the chassis. A hydraulic
fitting 2159b part of a hydraulic fluid line 2159c is threadably
coupled into port 2159a. Hydraulic line 2159c provides hydraulic
fluid into and out of the internal cylinder of brake assembly 2159,
or provides a bleed of trapped air and hydraulic fluid from the
internal cylinder. Preferably, port 2159a is located on assembly
2159 and adapted and configured such that no portion of hydraulic
line 2159c, including hydraulic fitting 2159b, is located inward of
innermost portion 2159d. As shown in FIG. 49, the brakes can be
actuated or bled from a hydraulic line, including the fittings,
that does not come closer to the wheel housing than the upright
portion of the wheel support. As shown and described, port 2159a is
oriented vertically upwards. However, the present invention also
contemplates those embodiments in which port 2159a can have any
orientation, so long as hydraulic line 2159c and fitting 2159b do
not extend inward of the innermost surface of the brake
assembly.
[0206] While the invention has been illustrated and described in
detail in the drawings and foregoing description, the same is to be
considered as illustrative and not restrictive in character, it
being understood that only the preferred embodiment has been shown
and described and that all changes and modifications that come
within the spirit of the invention are desired to be protected.
* * * * *