U.S. patent application number 12/231126 was filed with the patent office on 2009-01-01 for shock absorber apparatus.
Invention is credited to Peter Russell.
Application Number | 20090000892 12/231126 |
Document ID | / |
Family ID | 34426902 |
Filed Date | 2009-01-01 |
United States Patent
Application |
20090000892 |
Kind Code |
A1 |
Russell; Peter |
January 1, 2009 |
Shock absorber apparatus
Abstract
A shock absorber includes a first cylinder having a first fluid
port and a second cylinder having a second fluid port. A response
adjustment mechanism is connected in fluid transmission relation
between the first and second fluid ports. The response adjustment
mechanism includes three adjustable valves for controlling the
operation of the shock absorber. One of the adjustable valves has a
stem that is rotatable by a tool during operation. The remaining
adjustable valves each have a shaft that is rotatable by a tool
during operation. The adjustable valves of the response adjustment
mechanism are coaxially positioned so that a first valve is
coaxially positioned within a second valve, and the first and
second valves are coaxially positioned within a third valve.
Inventors: |
Russell; Peter; (Spokane,
WA) |
Correspondence
Address: |
MARK ALLISON BAUMAN
1910 SUNFLOWER COURT
COLLEGE PLACE
WA
99324
US
|
Family ID: |
34426902 |
Appl. No.: |
12/231126 |
Filed: |
August 29, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10961511 |
Oct 7, 2004 |
7441640 |
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12231126 |
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60509833 |
Oct 8, 2003 |
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60537429 |
Jan 15, 2004 |
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Current U.S.
Class: |
188/322.15 |
Current CPC
Class: |
F16F 9/486 20130101;
F16F 9/466 20130101; F16F 9/49 20130101; F16F 9/3488 20130101; F16F
9/342 20130101; F16F 9/065 20130101; F16F 2230/42 20130101 |
Class at
Publication: |
188/322.15 |
International
Class: |
F16F 9/342 20060101
F16F009/342 |
Claims
1. A shock absorber apparatus, comprising: a housing; a cylinder
bore enclosed by the housing, and further having a longitudinal
axis; a rod substantially positioned concentric to, and along, the
longitudinal axis of the cylinder bore; a piston fastened
concentrically to the rod, and positioned within the cylinder bore
in movable relation; a pressure plate positioned around the rod in
sliding relation, and positioned adjacent to the piston; a plate
spring retainingly bourne by the pressure plate in flexing
relation; a helical spring positioned around the rod, and having a
first end and an opposite second end, wherein the first end is
positioned in stacking relation to the plate spring, and wherein
the second end is held in fixed relation to the piston.
2. The shock absorber apparatus as claimed in claim 1, and wherein
the pressure plate comprises: a base surface having a center and a
perimeter; a rim extending in a perpendicular direction from the
base surface, and around the perimeter of the base surface; a floor
surface formed parallel to the base surface, and bounded by the
rim, and formed at a first distance from the base surface; an
aperture formed in the pressure plate, and extending from the base
surface through the floor surface; and a plurality of shelves
formed parallel to the base surface, and extending from the rim
toward the center, and wherein each shelf has a first surface and
an opposite second surface.
3. The shock absorber apparatus as claimed in claim 2, and wherein
the plate spring is retained by the pressure plate so that the
spring plate is supported by the first surface of one or more
shelves, and wherein the plate spring is retained by the second
surface of one or more shelves.
4. The shock absorber apparatus as claimed in claim 3, and wherein
the plurality of shelves further comprise: one or more shelves
having of a first length dimension; one or more shelves having a
second length dimension; and wherein the spring plate is supported
by the first surface of the one or more shelves having the first
length dimension, and wherein the spring plate is retained by the
second surface of the one or more shelves having the second length
dimension, and further wherein the first length dimension has a
value that is greater than the second length dimension.
5. The shock absorber apparatus as claimed in claim 4, and wherein
the plurality of shelves each have a center, and wherein the center
of each shelf is positioned at a regular angular interval in
angular spaced relation, one to another, so that the plurality of
shelves populate are located around the rim, and wherein each shelf
that has the first length dimension is positioned in angular order
next to a shelf that has the second length dimension.
6. The shock absorber apparatus as claimed in claim 5, and wherein
the spring plate comprises: a plurality of shims positioned in
stacking relation, one to another.
7. A shock absorber apparatus, comprising: a housing; a cylinder
bore enclosed by the housing, and having a longitudinal axis; a rod
having a first end and an opposite second end, and wherein the rod
is substantially positioned concentric to, and along, the
longitudinal axis of the cylinder bore, and wherein the first end
of the rod is positioned within the cylinder bore; a piston
fastened concentrically to the rod, and movably positioned within
the cylinder bore; a step washer positioned concentrically around
the rod in stacking relation, and positioned proximate to the
piston; a pressure plate positioned concentrically around the step
washer in sliding relation; a plate spring positioned
concentrically around the rod so that it is borne by the step
washer, and further wherein a portion of the plate spring is held
in tension by the pressure plate.
8. The shock absorber apparatus as claimed in claim 7, and wherein
the step washer further comprises a first thickness dimension; and
wherein the pressure plate further comprises an outside diameter,
and an aperture formed therein, and wherein the pressure plate has
an inner edge defined by the aperture, and wherein the inner edge
has a second thickness dimension, and wherein the pressure plate is
positioned around the step washer in sliding relation so that the
step washer extends through the aperture of the pressure plate; and
wherein the plate spring further comprises an outer edge, and
having an aperture formed therein, and wherein the plate spring has
a first region bounded by the outer edge of the plate spring and
extending inwardly by a first distance, and wherein the plate
spring has a second region bounded by the aperture and extending
outwardly by a second distance; and wherein a portion of the outer
region of the plate spring is borne by the pressure plate, and
wherein a portion of the inner region of the plate spring is borne
by the step washer; and further wherein the first thickness
dimension is greater than the second thickness dimension; and
further wherein the first distance and the second distance are less
than the outside diameter of the pressure plate divided by 6.
9. The shock absorber apparatus as claimed in claim 8, and further
comprising: a shim positioned on the rod in stacking relation, and
positioned between the piston and the pressure plate.
10. The shock absorber apparatus as claimed in claim 9, and wherein
the pressure plate is positioned adjacent to the piston in stacking
relation, and wherein the step washer is positioned adjacent to the
piston in stacking relation.
11. The shock absorber apparatus as claimed in claim 7, and wherein
the pressure plate further comprises: an outer cylindrical surface
defined by the perimeter of the pressure plate; a first surface
extending outwardly from the inner edge of the pressure plate to
the outer cylindrical surface, and wherein the first surface is
substantially flat; a second surface oppositely positioned from the
first surface, and extending outwardly from the inner edge of the
pressure plate to the outer cylindrical surface; a plurality of
ridges, each having a first height dimension, and wherein the first
height dimension is defined by a thickness of the pressure plate at
the location of the ridge, and wherein each ridge is defined by
extending a sector of the second surface from the inner edge of the
pressure plate outwardly to the outer cylindrical surface, wherein
the sector of the second surface is characterized by a curve
forming an apex proximate to the outer cylindrical surface; a
plurality of valleys, having a second height dimension, and wherein
the second height dimension is defined by a thickness of the
pressure plate at the location of the valley, wherein each valley
is defined by extending another sector of the second surface from
the inner edge of the pressure plate outwardly to the outer
cylindrical surface, wherein the sector of the second surface is
characterized by a gradual curve; and wherein each valley is
positioned adjacent to each ridge; and wherein the first height
dimension is greater than the second height dimension.
12. The shock absorber apparatus as claimed in claim 10, and
wherein the first region of the plate spring is borne by the
plurality of ridges of the pressure plate.
13. The shock absorber apparatus as claimed in claim 12, and
wherein the plate spring further comprises: a plurality of shims
positioned in stacking relation, one upon another.
14. The shock absorber apparatus as claimed in claim 11, and
wherein the pressure plate further comprises: a third surface
interposed between the first surface and the outer cylindrical
surface, wherein the third surface has a shape, and wherein the
shape of the third surface is curved or stepped.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation application of U.S.
Utility application Ser. No. 10/961,511, filed Oct. 7, 2004, and
also claims priority to U.S. Provisional Application 60/509,833
filed on Oct. 8, 2003, and claims priority to U.S. Provisional
Application 60/537,429 filed on Jan. 15, 2004.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates to a shock absorber, and more
particularly to a shock absorber incorporating improved dampening
response mechanisms and more specifically to a shock absorber
having a versatile adjustable response mechanism for tuning the
performance of the shock absorber apparatus.
[0004] 2. Description of Related Art
[0005] Shock absorber systems have been in use for damping the
reaction forces experienced with wheeled vehicles throughout the
use of the wheel as a means of transport. Shock absorbers are well
known in the art and have been used successfully for many years to
improve the safety and handling of many types of vehicles. The
design of the shock absorber has often been challenging due to the
nature of the dynamic motion of a vehicle as it travels over widely
varying terrain and driving conditions. Shock absorber performance,
though improved over the last few decades, is still far from
optimum. Often, the constraints and criteria used in the design of
a shock absorber are counter to one another, and force the designer
to balance tradeoffs. The result is a shock absorber having
performance that often delivers compromising results.
[0006] In certain applications, shock absorber systems are taken to
extremes, providing even further challenges for the designer. For
example, in the field of off-road motorcycle racing, a shock
absorber is exposed to widely varying conditions as the vehicle is
raced along a course of travel. Furthermore, the performance of the
shock absorber system can make a dramatic impact on the safety and
performance of the motorcycle.
[0007] For optimum performance, the response of a shock absorber
often must be tuned or adjusted for the conditions in which it will
be used. However, many shock absorber systems available on the
market today have a limited tuning capability. Further, those with
an adjusting or tuning capability, are often difficult to adjust,
resulting in mal-adjustments of the shock absorber which degrades
the performance even further.
[0008] The motorcycle shock absorber is relied upon by riders to
provide comfort and stability as well as to enhance the performance
of the motorcycle. One of the preferences of riders over rough and
varied terrain, is to have the responsive handling while preventing
the bone jarring jolts to the rider created when the motorcycle
impacts into bumps on the terrain. In the motorcycle application,
the shock absorber must provide a steady and consistent ride over
flat terrain. The flat terrain will not create instantaneous
jarring reaction forces. The shock absorber will react to the flat
terrain with low speed control. The piston in the cylinder of the
shock absorber will translate in the cylinder at a low speed. The
shock absorber is required to provide a steady and consistent ride
over moderate terrain. The moderate terrain will create moderate
reaction forces that cause the shock absorber to translate at a mid
or medium speed. It is desirable for a shock absorber to have mid
or medium speed control for the moderate terrain where the shock
absorber is required to absorb occasional jolts while maintaining a
stiff response over the moderate terrain. In addition, the shock
absorber is required to provide a stable and consistent ride over
rough and choppy terrain. The rough and choppy terrain will cause
instantaneous jarring reaction forces on the shock absorber. The
shock absorber will react to the rough and choppy terrain with high
speed translation. The shock absorber needs high speed control for
the high speed translation. The shock absorber is required to
dampen the sudden impact forces without a hard stiff jolt.
Unfortunately, up to this point, it has been difficult to realize a
shock absorber, having a suitable response for the varying types of
terrain cited above.
[0009] There have been many attempts to some of these problems with
varying degrees of success. For example, U.S. Pat. No. 5,810,128
teaches an improved shock absorber having an improved transition
between a first and second damping rates. Yet further, U.S. Pat.
No. 6,446,771 provides an improved bleed function and non-return
valve arrangement. And further, U.S. Pat. No. 6,116,338 teaches an
improved compression stroke valve in an attempt to improve the
performance of a shock absorber system.
[0010] Several attempts have been made to overcome the deficiencies
found in the state-of-the-art shock absorbers by designing support
systems which reduce the effects of the inherent deficiencies in
state-of-the-art shock absorbers. For example, linkage systems have
been incorporated on vehicles to modify the motion experienced by
the shock absorber to better match it the vehicle system.
Unfortunately, while such attempts improve the performance, they
also add cost and weight to the vehicle.
[0011] Therefore, it is evident that a versatile and adjustable
shock absorber is needed to overcome these and other deficiencies
in the prior art. The subject invention for a shock absorber
apparatus overcomes the perceived shortcomings and detriments in
the prior art apparatuses and is the subject matter of the present
application.
SUMMARY OF THE INVENTION
[0012] A first aspect of the present invention relates to a shock
absorber apparatus, having a first cylinder defining a first
internal bore closed by a first end wall and an opposite second end
wall, and further has a first port connected in fluid transmission
relation to the first internal bore, and a second cylinder defining
a second internal bore closed by a first end wall and an opposite
second end wall, and a second port connected in fluid transmission
relation to the second internal bore, and a response adjustment
mechanism located adjacent to the second cylinder, and connected in
fluid transmission relation between the first port and second port,
and has three or more adjustment operators which are operable to
direct the fluid flow between the first port and the second
port.
[0013] Another aspect of the present invention relates to a shock
absorber apparatus, having a first cylinder defining a first
internal bore and having an internal diameter, and closed by a
first end wall, and further closed by an opposite second end wall,
and further having a first port connected in fluid transmission
relation to the first internal bore, and a rod having a first end
and an opposite second end, and wherein the rod movably extends
into the first internal bore through an aperture formed in the
first end wall so that the second end of the rod is positioned
concentrically within the first internal bore, and so that the
first end of the rod is positioned outside the first internal bore,
and a first piston fixedly attached to the rod at an intermediate
position located between the first and the second end of the rod,
and positioned concentrically within the first cylinder, and a
second piston fixedly attached to the rod proximate to the second
end of the rod, and positioned concentrically within the first
cylinder; a second cylinder defining a second internal bore closed
by a first end wall and an opposite second end wall, and having a
second port connected in fluid transmission relation to the second
internal bore, and having and a response adjustment mechanism
located adjacent to the second cylinder, and connected in fluid
transmission relation between the first cylinder port and the
second cylinder port, and wherein the response adjustment mechanism
is configured to provide three or more adjustments for tuning the
response of the shock absorber system.
[0014] Still further, another aspect of the present invention
relates to a shock absorber apparatus, having a housing comprising
a first internal bore having a diameter, and further comprising a
second internal bore having a diameter, and wherein the housing is
closed by a first end wall, and further closed by an opposite
second end wall, and a rod having a first end and an opposite
second end, and wherein the rod movably extends into the first
and/or second internal bore through an aperture formed in the first
end wall so that the second end of the rod is positioned
concentrically within the first internal bore or second internal
bore, and so that the first end of the rod is positioned outside
the housing, and a first piston having a diameter, and fixedly
attached to the rod at an intermediate position located between the
first and the second end of the rod, and positioned within the
first internal bore in sliding relation, and a second piston,
having a diameter, and fixedly attached to the rod proximate to the
second end of the rod, and positioned within the first and/or the
second internal bore in sliding relation, and wherein the diameter
of the first piston is approximately equal to the diameter of the
first internal bore, and wherein the diameter of the second piston
is approximately equal to the diameter of the second internal bore,
and further wherein the diameter of the second piston is less than
the diameter of the first piston.
[0015] And still further, another aspect of the invention relates
to a shock absorber apparatus, having a first cylinder bore having
a diameter and having a longitudinal axis, and filled with an
incompressible fluid, and having a second cylinder bore having a
diameter, and filled with the incompressible fluid, and positioned
adjacent to the first cylinder bore, and along the longitudinal
axis of the first cylinder bore, and having a piston rod having a
first end, and an opposite second end, and a longitudinal axis, and
an external surface, and wherein the first end is positioned
outside the first and second cylinder bore, and wherein the second
end is positioned within the first or the second cylinder bore, and
the longitudinal axis of the piston rod is positioned concentric
to, and along, the longitudinal axis of the first cylinder bore,
the piston rod further comprising a bore formed concentrically
therein, and wherein the piston rod further comprises a one or more
of apertures formed within the piston rod and extending from the
external surface of the piston rod into the bore of the piston rod
to form a fluid passage, and having a first piston positioned at an
intermediate position located between the first and the second end
of the piston rod, and configured to translate within the first
cylinder bore in response to an external force, and having a second
piston positioned proximate to the second end of the piston rod,
and configured to translate within the first cylinder bore, and in
the second cylinder bore, and in response to the external force,
and a needle assembly located substantially within the second
cylinder bore, and configured to enter the bore of the piston rod
as the second piston nears the second cylinder bore, and wherein
the diameter of the second cylinder bore is less than the diameter
of the first cylinder bore.
[0016] Yet further, another aspect of the invention relates to a
shock absorber apparatus, having a housing, and a cylinder bore
enclosed by the housing, and further having a longitudinal axis,
and a rod substantially positioned concentric to, and along, the
longitudinal axis of the cylinder bore, and partially positioned
within the cylinder bore; a piston fastened to the rod, and
slidingly positioned within the cylinder bore, and a pressure plate
slidingly positioned on the rod, and positioned adjacent to the
piston, and a plate spring retainingly mounted to the pressure
plate.
[0017] And another aspect of the invention relates to a shock
absorber apparatus having a housing, and a cylinder bore enclosed
by the housing, and having a longitudinal axis, and a rod having a
first end and an opposite second end, and wherein the rod is
substantially positioned concentric to, and along, the longitudinal
axis of the cylinder bore, and wherein the first end of the rod is
positioned within the cylinder bore, and a piston fastened
concentrically to the rod, and movably positioned within the
cylinder bore, and a step washer positioned concentrically around
the rod in stacking relation, and positioned proximate to the
piston, and a pressure plate positioned concentrically around the
step washer in sliding relation, and a plate spring positioned
concentrically around the rod so that it is borne by the step
washer, and further wherein a portion of the plate spring is held
in tension by the pressure plate.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Preferred embodiments of the invention are described below
with reference to the following accompanying drawings.
[0019] FIG. 1 is a simplified cross-sectional view of a shock
absorber apparatus showing some of the features of the present
invention.
[0020] FIG. 2 is a simplified cross-sectional view of a variation
of the shock absorber apparatus.
[0021] FIG. 3 is a simplified partial cross-sectional view of a
piston rod in two positions defining the stroke length of the shock
absorber apparatus.
[0022] FIG. 4 is a simplified partial cross-section of a portion of
the shock absorber apparatus with a groove formed in the wall of
the housing or cylinder body.
[0023] FIG. 5 is a sectional view of the housing or cylinder body
and the first piston with a groove formed in the wall of the
housing or cylinder body.
[0024] FIG. 6 is a partial cross-sectional view of a portion of the
shock absorber apparatus including the second piston and needle
assembly.
[0025] FIG. 7 is a cross-sectional view of a needle assembly in the
shock absorber apparatus.
[0026] FIG. 8A is a partial cross-sectional view of a portion of
the shock absorber apparatus including the second piston and needle
assembly as the piston rod is distant from the needle assembly.
[0027] FIG. 8B is a partial cross-sectional view of a portion of
the shock absorber apparatus including the second piston and needle
assembly as the needle assembly enters a bore in the piston
rod.
[0028] FIG. 8C is a partial cross-sectional view of a portion of
the shock absorber apparatus including the second piston and needle
assembly as the second piston is adjacent to a sleeve.
[0029] FIG. 9 is a simplified cross-sectional view of a response
adjustment mechanism with a general border shown for three of the
adjustment valves.
[0030] FIG. 10 is a simplified cross-sectional view of the response
adjustment mechanism in the shock absorber apparatus.
[0031] FIG. 11 is an elevation view of a stem of the needle valve
in the response adjustment mechanism.
[0032] FIG. 12 is a cross-section view of a shaft that retains the
stem of the needle valve in the response adjustment mechanism.
[0033] FIG. 13 is bottom view of a first base element in the
response adjustment mechanism.
[0034] FIG. 14 is cross-sectional view of the second base element
in the response adjustment mechanism.
[0035] FIG. 15 is a plan view of the second base element in the
response adjustment mechanism.
[0036] FIG. 16 is a cross-sectional view of a screw in the response
adjustment mechanism.
[0037] FIG. 17 is a bottom view of the screw in the response
adjustment mechanism.
[0038] FIG. 18 is a cross-sectional view of a disc in the response
adjustment mechanism.
[0039] FIG. 19 is a plan view of the disc in the response
adjustment mechanism.
[0040] FIG. 20 is a cross-sectional view of a plate in the response
adjustment mechanism.
[0041] FIG. 21 is a bottom view of the plate in the response
adjustment mechanism.
[0042] FIG. 22A is a perspective view of a first type of a third
base in the response adjustment mechanism.
[0043] FIG. 22B is a perspective view of a second type of the third
base in the response adjustment mechanism.
[0044] FIG. 23 is a cross-sectional view of the second type of the
third base in the response adjustment mechanism.
[0045] FIG. 24 is a bottom view of the third base in the response
adjustment mechanism.
[0046] FIG. 25 is a cross-sectional view of a second shaft in the
response adjustment mechanism.
[0047] FIG. 26 is a plan view of the second shaft in the response
adjustment mechanism.
[0048] FIG. 27 is a cross-sectional view of a third shaft in the
response adjustment mechanism.
[0049] FIG. 28 is a plan view of the third shaft in the response
adjustment mechanism.
[0050] FIG. 29 is an elevation view of an example of a second
spring formed from a plurality of cup springs in the response
adjustment mechanism.
[0051] FIG. 30 is a partial plan view of the response adjustment
mechanism.
[0052] FIG. 31 is a simplified cross-sectional view of a first type
of progressive fluid control valve.
[0053] FIG. 32 is a simplified cross-sectional view of a second
type of progressive fluid control valve.
[0054] FIG. 33A is a simplified cross-sectional view of the second
type of progressive fluid control valve as the piston rod
translates at a low compressive speed in the shock absorber
apparatus.
[0055] FIG. 33B is a simplified cross-sectional view of the second
type of progressive fluid control system as the piston rod
translates at a medium compressive speed in the shock absorber
apparatus.
[0056] FIG. 33C is a simplified cross-sectional view of the second
type of progressive fluid control system as the piston rod
translates at a high compressive speed in the shock absorber
apparatus.
[0057] FIG. 34 is a plan view of a step washer in the shock
absorber apparatus.
[0058] FIG. 35A is an elevation view of a first type of step washer
in the shock absorber apparatus.
[0059] FIG. 35B is an elevation view of a second type of step
washer in the shock absorber apparatus.
[0060] FIG. 35C is an elevation view of a third type of step washer
in the shock absorber apparatus.
[0061] FIG. 35D is an elevation view of a fourth type of step
washer in the shock absorber apparatus.
[0062] FIG. 36 is a plan view of the first type of the pressure
plate in the shock absorber apparatus.
[0063] FIG. 37 is a cross-sectional view of the first type of the
pressure plate in the shock absorber apparatus.
[0064] FIG. 38A is a cross-sectional view of a pressure plate with
a first type of base contour as it is positioned around the step
washer.
[0065] FIG. 38B is a cross-sectional view of a pressure plate with
a second type of base contour as it is positioned around the step
washer.
[0066] FIG. 38C is a cross-sectional view of a pressure plate with
a third type of base contour as it is positioned around the step
washer.
[0067] FIG. 38D is a cross-sectional view of a pressure plate with
a fourth type of base contour as it is positioned around the step
washer.
[0068] FIG. 39A is a side perspective view of a second type of
pressure plate in the shock absorber apparatus.
[0069] FIG. 39B is a side perspective view of a third type of
pressure plate in the shock absorber apparatus.
[0070] FIG. 39C is a side perspective view of a fourth type of
pressure plate in the shock absorber apparatus.
[0071] FIG. 40 is a cross sectional view of a third type of
progressive fluid control valve.
[0072] FIG. 41 is a plan view of a pressure plate and plate spring
utilized in the third type of progressive fluid control valve.
[0073] FIG. 42 is a plan view of the pressure plate utilized in the
third type of progressive fluid control valve.
[0074] FIG. 43 is cross-sectional view of the pressure plate
utilized in the third type of progressive fluid control valve.
[0075] FIG. 44 is an alternate cross-sectional view of the pressure
plate utilized in the third type of progressive fluid control
valve.
[0076] FIG. 45 is a plan view of the plate spring utilized in the
third type of progressive fluid control valve.
[0077] FIG. 46 is an elevation view of one side of the pressure
plate and plate spring utilized in the third type of progressive
fluid control valve.
[0078] FIG. 47 is an elevation view of an alternate side of the
pressure plate and plate spring utilized in the third type of
progressive fluid control valve.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0079] This disclosure of the invention is submitted in furtherance
of the constitutional purposes of the U.S. Patent Laws "to promote
the progress of science and useful arts" (Article 1, Section
8).
[0080] Referring to FIG. 1, an exemplary shock absorber constructed
in accordance with an embodiment of the invention is identified
generally by the reference numeral 10. The shock absorber 10 is
designed to be positioned between a vehicle chassis (not shown),
and a wheel-carrying hub (not shown) in a manner known in the art.
The suspension unit 10 includes a cylinder assembly or housing 12
which is provided with a first end wall or cap 14. The end wall 14
carries a bracket 16 so as to provide a pivotal connection to the
vehicle chassis (not shown).
[0081] The cylinder housing 12 having a longitudinal axis 272
includes a cylinder bore 24 that is closed at one end by the end
wall 14 and at the other end by the gland 20. The opposite end of
the cylinder housing 12 is enclosed by an end wall or cap 18 that
carries a sealing gland 20. A piston rod 22 extends through the
sealing gland 20 out of an aperture 23 formed in the wall 18 in a
sealing arrangement while providing a translational guide for the
rod 22 to allow the rod 22 to translate within the cylinder housing
12. The rod 22 has an elongated portion on which is carried a yoke
26 that provides the connection to the wheel-carrying hub (not
shown).
[0082] A coil compression spring 28 encircles the cylinder housing
12 and the exposed end external to the housing 12 of the piston rod
22. One end of this spring 28 rests against a collar 32 that is
connected to the cylinder housing 12. The opposite end of the
spring 28 rests against a spring retainer 30 that is carried by the
piston rod 22 and is adjacent to the yoke 26. In this arrangement,
the spring 28 will be loaded as the piston rod 22 moves relative to
the cylinder housing 12 upon suspension movement of the wheel or
hub relative to the chassis of the vehicle. A snubber 34 is carried
by the spring retainer 30 and will engage with the end cap 18 so as
to provide a cushioned, yet positive stop, providing a limit to the
total compression of the shock absorber 10.
[0083] Referring still to FIG. 1, the shock absorber 10 is
comprised of a first damping piston 36 and a second damping piston
38 having a reduced diameter. Each piston 36 and 38 are supported
on the piston rod 22 within the cylinder bore 24. The second
damping piston 38 approximately defines a first fluid chamber 44
between the piston 38 and the end wall 14. A second fluid chamber
42 is approximately defined between the two pistons 36 and 38 and a
third fluid chamber 40 is approximately defined between the first
fluid piston 36 and the gland 20. The fluid chambers 40, 42, and 44
are filled with a damping fluid such as hydraulic fluid.
[0084] The piston rod 22 has a reduced diameter portion generally
indicated by the numeral 46 which extends from a first end of the
rod 22 to a shoulder 48. This reduced diameter portion 46 is
configured to mount and translate in stacking arrangement the
components that assist in providing a variable response to external
forces. A washer 50 is positioned in resting relation to the
shoulder 70. A damping valve assembly 52A is positioned over the
reduced diameter portion 46 of the rod 22 adjacent to the washer
50. The first piston 36 is positioned adjacent to the damping valve
assembly 52A. Another damping valve assembly 52B is positioned
adjacent to the first piston 36. A spacing sleeve 56 is positioned
adjacent to the damping valve assembly 54B and is configured to
maintain a spatial distance between the two pistons 36 and 38. The
spacing sleeve 56 has an axial length which can be selected so as
to control the spacing between the pistons 36 and 38. Another
damping valve assembly 52C is positioned adjacent to the spacing
sleeve 56. The second piston 38 is positioned adjacent to the
damping valve assembly 52C. Another damping valve assembly is
positioned adjacent to the second piston 52D. A holding nut 62 is
positioned in a threaded arrangement onto the reduced diameter
portion 46 of the rod 22 and, when tightened appropriately,
provides a holding force to maintain a spatial relationship between
the first and second pistons 36 and 38. The damping valves 52A,
52B, 52C, and 52D may be similarly constructed, one to another, but
may vary in scale or in characteristics. Alternatively, the damping
valves 52A, 52B, 52C, and 52D may be constructed using differing
elements from each other, and constituting different styles of
damping valves.
[0085] The piston 36 is formed with damping flow passages (not
shown) which extend therethrough and will be discussed later. The
damping valve assembly 52A is interposed between the spacer plate
50 and the piston 36 and partially controls the flow from the
chamber 42 to the chamber 40. The damping valve assembly 52B is
interposed between the opposite side of piston 36 and the spacer
sleeve 56 received on the reduced diameter portion 46 of the piston
rod 22. The valve assembly 52B acts to partially control the flow
from the chamber 40 to the chamber 42.
[0086] Like the piston 36, the piston 38 has a series of flow
passages (not shown) that extend therethrough. Some of the flow in
a first direction from the chamber 44 to the chamber 42 occurs
through certain of these passages at a rate controlled by the
damping valve assembly 52D depending on the position of the second
piston 38. Flow from the chamber 42 to the chamber 44 is partially
controlled by the damping valve assembly 52C which is disposed on
the opposite side of the piston 36.
[0087] A further control damping arrangement may be incorporated so
as to provide further control of the damping rate. The end 64 of
the piston rod 22 that extends into the chamber 44 is provided with
a central bore 66. This central bore 66 extends generally to the
area where the shoulder 48 is formed. An orifice plate 68 is
provided that is at least partially closed by an adjustable
metering pin 70. The position of the metering pin 70 is controlled
by an adjusting rod 72 that extends through a further bore formed
in the rod 22. The opposite end of the adjustment rod 72 has a
rounded pin 73 attached thereto, and is positioned in force
transmission relation to a rebound adjustment screw 75. This
adjustment screw 75 permits external adjustment of the damping flow
through the orifice plate 68 controlled by the metering pin 70.
[0088] Still referring to FIG. 1, an arm 76 extends from the
cylinder housing 12 to an accumulator housing 78. The housing 78
has a first end wall 81 and a second end wall 83. A fluid passage
90 extends within and through the arm 76 to a first port 94 in
fluid communication with the chamber 44. A response adjustment
mechanism 88 is positioned in fluid communication with the fluid
passage 90. The response adjustment mechanism 88 is positioned in
fluid communication with a second port 92 which is positioned
adjacent to the accumulator housing 78 as will be discussed below.
The response adjustment mechanism 88 is configured to provide a
user specified variable adjustment to affect the damping
characteristics of the shock absorber 10. The response adjustment
mechanism 88 includes biasing members for controlling the response
of the shock absorber apparatus 10 by providing a user adjustment
for a plurality of speed ranges. The mechanism 88 can include at
least one of a low speed adjustment portion, a medium speed
adjustment portion, and a high speed adjustment portion. The low
speed adjustment portion of the mechanism 88 can include a needle
flow controller. The medium speed adjustment portion can include
biasing members configured to control damping fluid flow as a
function of the user adjustment and the pressure difference between
the ports 94 and 92. The high speed adjustment portion can include
high resistance biasing members configured to control damping fluid
flow as a function of the user adjustment and the pressure
difference between the ports 94 and 92. The construction and
operation of the mechanism 88 will be discussed in detail at a
later point in this specification.
[0089] A floating piston 80 is contained within a bore 82 of the
accumulator chamber 78. An inert gas such as nitrogen may fill a
chamber 84 formed on one side of the floating piston 80 so as to
maintain a fluid pressure on the fluid in the shock absorber
chambers 40, 42, 44 and in a chamber 86 formed on the head of the
floating piston 80. The inert gas may be inserted through charging
port 85 through the base of the accumulator 78.
[0090] The effective inside diameter of the cylinder bore 24 can be
reduced over a portion of its length to provide for an enhanced
dampening characteristic as the piston 38 approaches the wall 14.
In FIG. 1, a cylindrical insert or sleeve 98 shown as it is mounted
to the internal surface of the bore 24 of the cylinder housing 12
proximate to the wall 14. The sleeve 98 may include a taper 97 to
provide a gradual transition to the flow of fluid as the piston 38
approaches. The shape of the taper 97 may be selected to tayler the
transition to provide a desirable damping characteristic as the
piston 38 approaches and travels through the bore defined by the
sleeve 98.
[0091] Yet further, to enhance the damping characteristics of the
shock absorber apparatus 10, a needle assembly indicated generally
by the reference numeral 96 is mounted proximate to the end cap 14.
The needle assembly 96 is adapted to enter into the piston rod bore
66 and provide additional control therethrough as will be discussed
in greater detail below.
[0092] Referring now to FIG. 2, a variation of the shock absorber
apparatus 10 is shown. In this variation, the shape and form of the
sleeve 98 shown in FIG. 1 is incorporated into the cylinder or
housing 367. The housing 367 defines a first cylinder bore of 345
concentrically aligned along a longitudinal axis 358. A second
cylinder bore 346 is positioned adjacent and concentric to the bore
345. The first cylinder bore and the second cylinder bore each have
an inside diameter as generally indicated by the numeral 348 and
350, respectively. A piston rod 22 is concentrically located within
the first cylinder bore 345 and is allowed to translate through an
aperture 356 formed in the first end wall 354 of the housing
367.
[0093] In both FIG. 1, and FIG. 2, a second housing or cylinder 78
is positioned near the housing 12 (FIG. 1) and the housing 367
(FIG. 2). The cylinder or housing 78 holds an incompressible fluid
370 and compressible fluid 371. The fluid 370 and the fluid 371 are
separated by the piston 80. The response adjustment mechanism 88 is
configured in fluid communication with the incompressible fluid 370
as it is transferred to and from the bore in the housing 78 to the
housing 12 (FIG. 1) or the housing 367 (FIG. 2) via the channel or
passageway 90. Still further, the cylinder bore 24 (FIG. 1) or the
bore 345 (FIG. 2) can be configured with one or more grooves 356
formed into the housing 12 (FIG. 1) or housing 367 (FIG. 2). The
groove 356 is positioned proximate to the first piston 36 and will
be discussed in further detail below.
[0094] Now referring to FIG. 3, a portion of the shock absorber
apparatus 10 is shown having a piston rod 22 that is movable in
direction generally indicated by the arrow 344 through an aperture
23 (FIG. 1) through the first wall 18 of the housing or cylinder
12. The piston rod 22 is configured to translate within the bore 24
(FIG. 1) over a range of positions at varying speeds depending on
the external forces applied to the rod 22 and the pinion 16. The
piston rod 22 has a second end 64 and is shown in FIG. 3 at a first
position 338. For reference, when the end 64 of the rod 22 is
located at the first position, the apparatus 10 is said to be in
its returned state. A second reference point is shown at the point
where the end 64 is located at the position designated by the
numeral 340. At this point, the apparatus 10 is said to be in its
bottomed state. A distance generally designated by the numeral 342
is measured as the difference between the first position 338 and
the second position 340. The distance 342 may be considered the
stroke length of shock absorber apparatus 10. In this
specification, when the motion of the rod 22 is in the direction
designated by the arrow 344, the motion is said to be compressive;
when the motion of the rod 22 is in the direction designated by the
arrow 347, the motion is said to be returning.
[0095] Furthermore, a low speed definition consists of rod 22
travel anywhere in the stroke, from zero until the speed and volume
of the rod 22 may overcome a volume movement of liquid through the
low speed portion of the response adjustment mechanism 88 and the
dampening valve assembly movement that have been selected and set
per leverage and the speed of travel per the shock absorber
apparatus 10.
[0096] Furthermore, a medium speed definition consists of rod 22
travel anywhere in the stroke, from zero until the speed of the rod
22 travel has overcome the low speed settings and adjustments. A
rod 22 travel exceeds the resistance of a given low speed volume
control to another volume and resistant control. Within the given
volume of the rod 22 and stroke travel per leverage and speed of
travel per shock absorber apparatus 10.
[0097] Finally, a high speed definition consists of rod 22 travel
anywhere in the stroke from zero until the speed has over come the
low speed and mid speed adjustments for a given volume per shock
and leverage and the speed ratio. A high speed rod travel movement
consist of a supposed maximum speed traveled by the rod to control
all speeds that can overcome the low and mid speed pathways or rod
volume per low and mid speed.
[0098] Referring now to FIG. 4 and FIG. 5, a cylinder or housing 12
is shown position positioned along the longitudinal axis 272. The
piston rod 22 extends into the cylinder or housing 12 through an
aperture 23 as shown in FIG. 1. A first piston 36 is fastened to
the rod 22 and is translatable in a space formed by the housing or
cylinder 12 as generally indicated is the cylindrical bore having
the numeral 24. A first chamber 40 is defined by the position of
piston 36. A second piston 38 (FIG. 1) is shown, and also
positioned on the piston rod 22, and defines a second chamber 42
(FIG. 1). The cylinder or housing 12 defines an internal bore 24
that forms an internal surface 302. The surface 302 may include one
or more grooves 356 which are formed into the cylinder or housing
12. The groove 356 forms a communication channel between chambers
40 and 42, providing a bleed or bypass flow 360 when the first
piston 36 is proximate to the groove 356. The groove 356 provides
an enhancement to the flow of the incompressible fluid around the
first piston 36 and can be configured to affect a desirable
dampening characteristic. The location of the one or more grooves
356 may provide a variable damping characteristic that may be
configured by choosing the location, width, length, depth, and
taper of the groove 356 relative to the location of piston 36 and
the first position 338 (FIG. 3). In a preferred embodiment, the
groove is positioned proximate to the piston 36 when the shock
absorber apparatus is configured near its bottomed state, and has
an initial depth at the first end of the groove 356 proximate to
the end wall 18, and further has a depth that is taped along its
length so that the depth at a second opposite end 356 is less than
the depth at the first end. The groove 356 has been shown to
provide a desirable dampening characteristic during low-speed
operation of the shock absorber apparatus 10.
[0099] Now referring to FIG. 6 a simplified view of the upper
portion of the shock absorber apparatus is shown. A sleeve 98 a
shown position proximate to the second end wall 14 of the housing
or cylinder 12. The sleeve 98 has an outside diameter 277 and an
inside diameter 276 and is positioned along and concentric to the
longitudinal axis 272. A first piston 36 is shown having an outside
diameter as generally indicated by the numeral 274 positioned on
the piston rod 22 (FIG. 1). A second piston 38 is shown having an
outside diameter as is generally indicated by the numeral 279 and
is positioned near the second end 64 of the piston rod 22 as shown
in FIG. 1. A needle assembly 96 is shown attached to the second
wall 14 of the housing or cylinder 12 and extends into the second
cylindrical bore 24. A piston rod 22 includes a bore 66 which is
drilled concentrically through its length.
[0100] The outer diameter 274 of the piston 36 is selected so that
the piston 36 may move in a sealing fashion within the cylinder
bore 24. This outside diameter 274 is approximately equal to the
dimension 277 is only different by the amount of clearance required
for tolerance and to provide a slideable fit. Similarly, the second
piston 38A has the outside diameter 279 is configured with an
outside diameter similar to the inside diameter of the sleeve 98 as
indicated by a the dimension 276. The dimension 279 and the
dimension 276 are approximately equal and are selected such that
the second piston 38 is able to movably translate within the
cylindrical bore 24.
[0101] The piston 38A is shown as a variation of piston 38 having a
cup shaped surface 39 defining a crown 43 having a height dimension
generally indicated by the numeral 41. The piston 38A also may have
a cylindrical shape without the indentation shown on piston 38 for
the sealing band. For this specification, piston 38A and piston 38
are identical in other respects.
[0102] Still referring to FIG. 6, a needle assembly 96 is
positioned adjacent to the second and wall 14 of the housing or
cylinder 12. The needle assembly is concentrically positioned along
the longitudinal axis 272 of the bore 24. The needle assembly 96
extends from the second wall 14 toward opposite end of the cylinder
bore 24 and extends beyond the edge 97 of the sleeve 98. The needle
assembly 96 may be configured with straight sides, or
alternatively, may have a taper to accomplish a damping
characteristic. Regardless of the shape of the needle assembly 96,
however, the outside diameter of the assembly 96 is selected to fit
within the bore 66 of the rod 22 as the hydraulic apparatus
approaches its bottomed state. The piston rod 22 further includes
one or more apertures 366 formed therein and extending to the bore
66 to provide a fluid path as will be discussed below.
[0103] Referring now to FIG. 7, a needle assembly 96 is shown. The
assembly 96 includes a needle member 285 having a bore 284 and a
first end 281 an opposite second end 282. The needle member 285 may
be tapered over its length to affect a dampening characteristic of
the shock absorber 10. The first end 281 is attached to the wall 14
(FIG. 1) or alternatively to 353 (FIG. 2). The member 285 has an
end wall 283 positioned proximate to the end 282. An aperture 286
is formed in the wall 283 forming a fluid passage between the bore
284 and the bore 24 when it is unobstructed. Another aperture 288
is formed on the surface of the member in intermediate position
between and the end 281 and the end 282. A helical spring 291 is
shown inserted into the member 285 and is shown extending from the
end 281 to the end 282. The first end 292 of the spring 291 is
positioned adjacent to a sphere 290. From the drawing, it should be
apparent that the sphere 290 and the spring 291 may move within the
tube 285 within the bore 284. This sphere 290 is shown positioned
adjacent to the aperture 286 and serves to obstruct the aperture
286 reducing or blocking the fluid passage formed by the
combination of the aperture 286 to the bore 284 to the aperture 288
when the force upon the sphere 290 imparted by the incompressible
fluid is insufficient to overcome the load provided by the spring
291 in concert with the gravitational force and inertial forces
exerted on the sphere. A fluid flow (not shown) may enter the
aperture 286 and flow through the bore 284 an exit the aperture 288
causing an upward force on the sphere 290 which causes the spring
291 to contract allowing fluid flow freely. Alternatively if there
is a pressure at the aperture 288 which initially causes fluid to
flow from 288 to the aperture 286 this will cause a force on the
sphere 290 to cause it to translate towards the end 282 until it
contacts and it reduces or restricts the fluid flow between the
aperture 288 and the aperture 286. In this respect, it should be
understood, that the needle assembly 96 may act as a check valve
allowing flow from the aperture 286 to the aperture 288 and
restricting flow that from the aperture 288 to the aperture 286.
The tube 285 has an outside diameter generally indicated by the
dimensional measurement 275 and is configured to be less than the
inside bore 66 diameter within the piston rod 22. Thus, the
dimension 275 should be less than the dimension 278 (FIG. 6).
[0104] Now referring to FIGS. 8A, 8B, and 8C, a sequence is shown
of the shock absorber assembly with an interaction between the
piston rod 22 and the needle assembly 96 as well as an interaction
between the second piston 38 and the sleeve 98. As shown in FIG.
8A, the piston rod 22 is shown proximate end of the needle assembly
96. However, in the position shown, needle assembly 96 has not yet
entered the bore 66 of the rod 22. Now referring to FIG. 8B, the
rod 22 is shown in an advance position relative to the position
shown in FIG. 8A. As shown in the drawing, the assembly 96 has
entered the bore 66 of the rod 22. Now referring to FIG. 8C, the
needle assembly 96 is shown partially engaged in the bore 66 of the
rod 22. Furthermore, the second piston 38 is shown in a position
that is adjacent to the sleeve 98.
[0105] Now referring to FIG. 9, the response adjustment mechanism
88 is shown in a cross sectional view. The response adjustment
mechanism 88, and in a preferred embodiment, includes three
adjustable valves concentrically located and coaxially positioned,
one within the other, and along a longitudinal axis 100. A first
adjustment valve 103 is shown as the innermost valve, and centered
along the longitudinal axis 100. A third adjustment valve 107 is
shown as the outermost valve, and centered about the longitudinal
axis 100. A second adjustment valve 105 is shown positioned between
the first adjustment valve 103 and the third adjustment valve 107,
and centered about the longitudinal axis 100. The drawing includes
several boundary lines that generally indicate the components
associate with each adjustable valve in the response adjustment
mechanism. It should be understood that this boundary line provides
only a general representation, since some of the elements of the
valves are shared amongst themselves.
[0106] A boundary line generally indicated by the numeral 102
provides a guideline boundary generally indicating the elements
included to make the first adjusting valve in the response
adjustment mechanism 88. The valve bounded by the guideline
boundary 102 is a type of needle valve whose construction will
discussed in further detail below. A boundary line generally
indicated by the numeral 104 provides a guideline boundary
generally indicating the elements included in the second adjusting
valve in the response adjustment mechanism 88. The valve bounded by
the guideline boundary 104 includes a bore 106 that is configured
to receive the valve bounded by the guideline boundary 102 in
coaxial relation. The valve bounded by the guideline boundary 104
is a type of valve that controls the flow as a function of the
pressure on the valve, which in this specification, is referred to
as a pressure controlled valve, whose construction will be
discussed in further detail below. A boundary line generally
indicated by the numeral 108 provides a guideline boundary
generally indicating the elements included in the third adjusting
valve in the response adjustment mechanism 88. The valve bounded by
the guideline boundary 108 includes an element 110 that is
configured to receive the valve bounded by the guideline boundary
102 in coaxial relation. The valve bounded by the guideline
boundary 108 is a type of valve that controls the flow as a
function of the pressure on the valve, which in this specification,
is referred to as a pressure control valve, whose construction will
be discussed in further detail below.
[0107] Now referring to FIGS. 1, 10 and 11, the response adjustment
mechanism 88 is positioned in fluid communication between the port
92 and the port 94 of the shock absorber assembly 10. The mechanism
88 is positioned concentrically to, and along a longitudinal axis
100. A stem 112 is concentrically positioned along the longitudinal
axis of 100. The stem 112 includes a first end 116 and an opposite
second end 118 with thread 120 formed in the outer surface 114
proximate to the second end 120. A notch 260 is formed on the end
116 and is generally configured to allow a user to adjust the
longitudinal position of the second end 120 using a screwdriver as
an adjustment tool as will be discussed in greater detail below.
The end 118 has conical shape or needle characteristic which is
used to control the flow to and from the ports 94 and 92 during
operation of the shock absorber 10.
[0108] Now referring to FIGS. 10 and 12, a shaft 122 is shown
having a first end 137 and an opposite second end 138. A first bore
126 is formed concentrically within the shaft 122 and extends from
the end 137 to an intermediate position between the end 137 and the
end 138. A second bore 128 formed concentrically within the shaft
122 extends from the end 138 to the bore 126. The bore 128 has an
inner surface 132 with threads 134 form therein. The shaft 122 has
an outer surface 124, wherein the outer surface has a plurality of
steps. Threads 125 are formed in the outer surface 124 at an
intermediate position between the end 137 and the end 138. The
shaft 122 is configured to receive the stem 112 so that the end 116
of the stem 112 is inserted into the bore 128 and further extended
into the bore 126. The stem 112 is brought further into the shaft
122 by engaging the threads 120 and the threads 138 together by
rotating the end 116 using a screwdriver to lift the stem 112 into
the shaft 122 until the end 118 is proximate to the aperture 136
formed through the shaft 122. The amount of fluid passing between
the port 94 and the port 92 may be controlled by adjusting the
longitudinal position of the end 118 relative to the aperture 136.
As will be understood, the amount of flow that may be controlled
using the valve 112 in combination with the shaft 122 is low and
has been found to be most useful for controlling the response of
the shock absorber when the motion of the shock absorber apparatus
10 is in a low state. One skilled in the art will readily recognize
that the combination of the stem 112 and the aperture 136 in the
shaft 122 forms a needle valve which is useful for controlling the
flow of a fluid.
[0109] As best viewed by studying FIGS. 10, 25 and 26, a second
shaft 140 is shown positioned concentrically, and along the
longitudinal axis 100 of the response adjustment mechanism 88. The
shaft 140 has a first end 142 and an opposite second end 143. A
hexagonal recess 152 proximate to the end 142 of the shaft 140 is
provided for adjustment. The shaft 140 further comprises a bore 146
located proximate to the end 143. A second bore 148 extends from
the first bore 146 to an intermediate location between end 142 and
end 143. The bore 148 has threads 154 formed therein. A third bore
150 having a diameter less than the bore 148 a shown positioned
between the hexagonal recess 152 and the second bore 148. The shaft
140 has an outer surface 144 which has a small taper so that the
diameter of the surface 144 proximate to the end 143 is slightly
larger than the diameter of the surface 144 proximate to the end
142.
[0110] The shaft 140 is shown concentrically and coaxially aligned
with the stem 112 and the shaft 122. The shaft 140, threadingly
fastens to the shaft 122 by engaging the threads 154 on the shaft
140 with the threads 125 on shaft 122. In this manner, the relative
longitudinal position of the shaft 140 relative to the shaft 122
may be adjusted and set by rotating the shaft 140 relative to the
shaft 122. A spring 156 has a first end 157 and an opposite second
end 158. The spring 156 is shown in FIG. 10 positioned around and
generally concentric to the shaft 122. The end 143 of the shaft 140
is configured to contact the end 157 of the spring 156 in force
transmission relation so that the force stored in the spring 156 is
exerted on to the shaft 140. In this configuration, the shaft 140
provides a preload force to the spring 156. The second end 158 of
the spring 156 is borne by a first surface 161 of a first base 160.
Yet further, the first base 160 is borne by a second base 182.
[0111] Now referring to FIG. 13, a bottom view of the first base
160 is shown. The base 160 has a bore 164 which is configured to
provide a passage for the second end 138 of the shaft 122 to pass
therein. In this position, the first base 160 is concentrically
positioned around the first shaft 122 in sliding relation. Yet
further, the first base 160 includes a lip 163 configured to
concentrically position the first base 160 relative to the second
base 182.
[0112] As best seen in FIGS. 10, 14 and 15, the second base 182
includes a plurality of apertures 183 formed in the surface 192 as
shown in FIG. 15. The surface 192 forms a seat configured to bear
the first base 160. It should be understood from the drawing that
as the base 160 is borne by the surface generally indicated by the
numeral 192, the apertures 183 formed within the second base 182
are obscured by the base 160. The force stored in the spring 156
may be adjusted by rotating the second shaft 140 relative to the
first shaft 122, thereby increasing the force transmitted to the
first base. As fluid flows in response to an external force causing
motion in the shock absorber apparatus 10, a pressure is exerted on
the first base 160 resulting in an opposing force which works
against the force stored in the spring 156. When the opposing force
exerted on the first base 160 is sufficient to overcome the preload
force stored in the spring 156, the base 160 separates from the
surface 192 of the second base 182, opening an alternate path
through the apertures 183 for fluids to flow having less
resistance. The path for the fluid to flow in this situation, and
when the shock absorber apparatus is in a compressive state, may be
generally understood to occur through the second base 182 and a
plurality of apertures generally indicated by the numeral 199 as
shown in FIG. 10. As will be understood, the operation of the
combination of the spring 156, the shaft 140, the first base 160
and the second base 182 form a pressure controlled valve which is
useful for controlling the flow of fluid from port 94 to the port
92, and thereby providing a means to adjust the response of the
shock absorber 10.
[0113] The second base 182 as shown in FIGS. 14 and 15 is a
machined element having an outer surface 184, and having a first
surface 186 and an opposite second surface 188. The outer surface
184 is bound by the first surface 184 and the second surface 188.
The second base 182 also has a first concentric bore 190 that
extends from a first intermediate position between the first
surface 186 and the second surface 188 extending through to the
second surface 188. The first surface 186 has a recessed seat 192
formed therein. The second base 182 also has a second concentric
bore 194 extending from the first surface 186 to a second
intermediate position located between the first intermediate
position and the first surface 184. The second base 182 also has a
concentric cavity 196 that extends from the first intermediate
position to the second intermediate position as may be seen in FIG.
14.
[0114] Now referring to FIGS. 10, 16 and 17, a screw 214 having a
bore 220 formed therein is a shown having a head 218 which is
inserted into the cavity 199 of the second base 182. The screw 214
has a second end 217, and an outer surface having threads 216. The
threads 216 of the screw 214 threadably and rotatably inserted into
the internal threads of the first shaft 122 near the end 138 as
shown in FIG. 10. The screw 214 is configured to retainingly fasten
the shaft 122 and the second base 182 together. The screw 214 has
channels 219 formed into the head for enhancing fluid flow in the
cavity 196 of the second base 182. In addition, these channels 219
are a useful for rotating the screw 214 into the position within
the response adjustment mechanism 88.
[0115] Now referring to FIGS. 10, 27, 28 and 29, a third shaft 166
having a first surface 167 and an opposite second surface 168. The
shaft 166 is substantially concentrically aligned with the
longitudinal axis 100 of the response adjustment mechanism 88. The
third shaft 166 has a concentric bore 172 defining an internal
surface 174. The surface 174 is configured to engage the outer
surface 144 of the second shaft 140 in fastening relation. The
third shaft 166 also includes an outer surface 170 forming a
shoulder having threads 176 formed therein proximate to the surface
168. The surface 168 of the third shaft 166 is configured to
transmit a preload force to a spring 178. Yet further, a shoulder
is formed in the surface 168 which serves to act as a guide for the
spring 178. The spring 178 has an aperture (not shown) which
provides an opening so that the spring 178 is positioned around the
shaft 140 and the spring 156. The spring 178 may be comprised of a
stack of individual spring elements as shown in FIG. 29. In a
preferred embodiment, the spring elements may be of the cup spring
variety, with each spring having an aperture greater than the
outside diameter of the shaft 140. The individual spring elements
are generally indicated by the numeral 258. The spring 178 has a
first end 179 and an opposite second end 180. The first end 179 of
the spring 178 is positioned in force transmission relation to the
surface 168 of the third shaft 166. The second end 180 of the
spring 178 is positioned in force transmission relation to the
second base 182 so that the spring 178 is borne by the second base
182.
[0116] As it may be understood from studying FIG. 10, the second
base 182 is borne by a third base generally indicated by the
numeral 202. The third shaft 166 imparts a preload force to the
spring 178 by threadably engaging a housing 198 having internal
threads to provide an axial preload force directed along the
longitudinal axis 100. The housing 198 is retained by threadably
engaging a locking cup (not shown) with the outer threads on the
housing 198. A force is exerted upon the second base 182 when
motion is imparted on the shock absorber apparatus 10 that develops
a pressure difference between the port 94 and 92. This pressure may
exert an opposing force that is opposite in direction to the
preload force stored in the spring 178. When the opposing force is
sufficient to overcome the preload force in spring 178, the
opposing force will cause the second base 182 to separate from the
third base 202. When the second base 182 separates from the third
base 202, a relative large fluid flow passage is created in the gap
(not shown) between the second base 182 and the third base 202
allowing fluid to pass directly from the passage 90 (FIG. 1) out
the apertures 199 to the port 92 (FIG. 1) of the shock absorber
apparatus 10. The amount of preload force may be preset by rotating
the third shaft 166 by engaging the wrench flats generally
indicated by the numeral 264 (FIG. 28) using a wrench or other
suitable tool.
[0117] Referring now to FIGS. 22A, 22B, 23 and 24, several styles
of the third base 202 that have been developed, and are indicated
generally by the designations 202A and 202B. The third base 202 has
a first surface 203 and an opposite second surface 204. Yet
further, the third base 202 has a first cavity 206 having an inner
surface 208 that is bounded by the first surface 203 and extends to
an intermediate position between the first surface 203 and the
second surface 204. The inner surface 208 is configured to support
the outer surface 184 of the second base 182. The third base 202
has a second cavity 210 extending from the intermediate position to
the second surface 204. The second cavity 210 defines a third
surface 212 that is positioned proximate to the intermediate
position. A plurality of apertures 201 are formed in the third base
203 and connected by an internal passage (not shown) to the
plurality of apertures 205 formed in the third surface 212. These
internal passages are useful for providing return fluid flow
between port 92 (FIG. 1) and the passage 90 (FIG. 1). The apertures
199 shown in FIG. 22B are similar to the apertures 199 shown in
FIG. 10 and are formed in the third base 202B rather than in the
housing 198.
[0118] Now referring to FIGS. 10 and 24, a washer or plate 266 is
positioned adjacent to the surface 212 of the third base 202. A
spring 268 having a first end 269 and an opposite second end 270 is
positioned with the first end 269 of the spring 268 positioned
proximate the washer or plate 266. The end 270 of the spring 268 is
borne by a notch formed in the third base 202 in retaining
relation. In this configuration, the washer or plate 266 obscures
the apertures 205 formed in the surface 212 of the third base 202.
The pressure in the fluid from port 92 to the port 94 may exert a
force on the washer or plate 266 in an opposite direction to a
force stored in the spring 268. When the force generated by the
pressure in the fluid is sufficient, the spring 268 will allow the
plate or washer 266 to separate from the surface 212 of the third
base 202 permitting fluid to flow from the port 92 to the port 94.
In an alternate situation, when the pressure is greater at port 94
relative to port 92, the force exerted on the plate or washer 266
is in the opposite direction and further forces the plate or washer
266 against the surface 212 of the third base 202 effectively
blocking the apertures 205. In this configuration, the combination
of the washer or plate 266, the spring 268, and the shoulder of the
third base 202 forms a check valve restricting the flow through the
path formed from the aperture 201 to the aperture 205 in the third
base 202 when the pressure is greater at the port 94 relative to
the port 92 in the shock absorber apparatus 10.
[0119] Now referring to FIGS. 10, 18, 19, 20 and 21, a spring 224
is positioned concentrically along the longitudinal axis 100 of the
response adjustment mechanism 88. The spring 224 is helical spring
having a first end that is bounded by the screw 214. An opposite
end of the spring 224 is borne by a disc 226. The disc 226 has a
first surface 227 and an opposite second surface 228. A bore 230 is
formed between the first surface 227 to an intermediate surface
positioned between the first surface 227 and second surface 228
generally indicated by the numeral 234. A bore or aperture 232 is
formed into the surface 234 and extends through the surface 228.
The surface 234 of the disc 226 is configured to seat and contain
an end of the spring 224 in force transmission relation. The outer
surface 235 of the disc 226 is configured to slidingly translate
within the bore 190 (FIG. 14) of the second base 182.
[0120] A plate 236 is borne by the second base 182 in fitting
relation. The plate 236 has a first surface 237 and an opposite
second surface 238, and a concentric shoulder 240 proximate to the
second surface 238. The plate 236 also has an outer concentric
surface 242 extending from the concentric shoulder 240 to the first
surface 237. A concentric bore 244 extends from the surface 237
through the surface 238. The plate 236 further has a plurality of
apertures 250 and 252, each having a longitudinal axis, 246 and 248
respectively, extending from the second surface 238 to an
intermediate position between the first surface 237 and the second
surface 238. The plate 236 also has a plurality of bores 254 and
256 centered along the longitudinal axis of each aperture, 246 and
248 respectively, extending from the first surface 237 to the
intermediate position.
[0121] The combination of the plate 236, the disc 226, and the
spring 224 within the second base 182 form a baffle assembly which
is useful for controlling the flow of fluid to and from port 94 and
port 92. The baffle assembly serves to provide an additional
damping function useful for modifying the response of the shock
absorber apparatus.
[0122] Now referring to FIGS. 10 and 30, the response adjustment
mechanism 88 is provided with three separate user adjustments which
are useful for modifying the response of the shock absorber
apparatus 10. A first adjuster shown in FIG. 30 has a screw head
generally indicated by the numeral 260. The screw head 260 is
useful for controlling the position of the stem 112 relative to the
aperture 136 formed in the shaft 122 thereby providing an
adjustment which substantially controls the response of the shock
absorber 104 during low speed motion. A hexagonal recess generally
indicated by the numeral 262 permits the user to change the preload
of the spring 156 by changing the longitudinal position of the
shaft 140 relative to the first base 160. This adjustment controls
the amount of force required to dislodge the base 160 from the
second base 182 and is effective in substantially controlling the
response of the shock absorber apparatus 10 during periods of
medium motion. The hexagonal wrench flat 264 formed into the shaft
266 is useful for adjusting the preload of the spring 178 which
controls the amount of pressure required to cause the second base
182 to separate from the third base 202. By turning flat 264, the
shaft 166 is rotated relative to the second base 182 thereby
modifying the preload force on the spring 178. The adjustment
realized by the flat 264 allows the user to set the amount of force
required that must be overcome, by the fluid pressure in the shock
absorber apparatus 10 to dislodge the second base 182 from the
third base 202. Typically, a high level of force is required to
dislodge the second base 182 from the third base 202 relative to
the other adjustments. In this way, the adjustment 264 is useful
for controlling high speed motion in the shock absorber apparatus
10.
[0123] Now referring to FIGS. 31, 34, 35A, 36, 37 and 39A, a
damping valve assembly 52E and associated components will now be
described. A piston generally indicated by the numeral 312 is shown
mounted concentrically to the rod 22. A passage 313 formed in the
piston 312 allows fluid to pass from one side of the piston 313 to
the other side of the piston 313 as governed by the action of the
damping valve assembly 52E. A step washer 308 has an aperture 335
which forms an inside edge 336. The rod 22 is inserted into the
aperture 335 of the step washer 308 in stacking relation so that
the step washer 308 is adjacent to the piston 312. Yet further, the
step washer 308 has an outside diameter dimension generally
indicated by the numeral 333 and has a thickness dimension
generally indicated by the numeral 310. A pressure plate 314 has an
aperture 339 and a diameter dimension generally indicated by the
numeral 337. The aperture 339 of the pressure plate 314 forms an
inside edge 320 which has a thickness dimension generally indicated
by the numeral 322. The diameter dimension 337 of the pressure
plate 314 is selected to be greater than the outside diameter
dimension 333 of the step washer 308. Yet further, the thickness
dimension 322 of the inside edge 320 of the pressure plate 314 is
selected so it is less than the thickness dimension 310 of the step
washer 308. In this manner, the rod 22 and the step washer 308 are
inserted into the aperture 339 of the pressure plate 314 in sliding
relation so that both the step washer 308 and the pressure plate
314 are adjacent to the piston 312 when a preload force is applied
to the pressure plate to hold it against the piston 312. A plate
spring 309 having an aperture 326 is positioned in stacking
relation around the piston rod and adjacent to the step washer 308.
A plurality of other plate springs 444 may be positioned in
stacking relation one to another around the piston rod and adjacent
to the plate spring 309. A retaining means (not shown) is
configured to fixedly hold the other plate springs 444, plate
spring 309, and the step washer 308 in stacking relation to the
piston 312. The retaining means may include but is not limited to a
sleeve, nut, shoulder of a shaft or other forms of mechanically
securing elements to a rod 22 in stacking relation.
[0124] The pressure plate 314 has a ridge or ledge 434 and that has
a thickness dimension generally indicated by the numeral 436. The
pressure plate 314 is further selected so the thickness dimension
436 is greater than the thickness dimension 310 of the step washer
308. The difference between the thickness dimension 436 and the
thickness dimension 310 defines an initial deflection distance of
the plate spring 309 as the plate spring 309 is held in tension by
the pressure plate 314. This initial deflection distance is
graphically represented in FIG. 38A and is as generally designated
by the numeral 307. This initial deflection distance of the plate
spring 309 generates a preload force which acts on the pressure
plate 314 causing it to rest adjacent to the piston 312 as shown in
FIG. 31. The amount of preload force may be selected by adjusting
the difference in thickness dimension, as well as by varying the
effective spring rate of the combined spring 309 and other springs
444.
[0125] Now referring to FIG. 31, the plate spring 309 may be
considered to have two distinct regions which are generally
designated by the numerals 328 and 329. The region 329 is defined
as originates from the edge of the aperture 326 of the plate spring
309 and extending outwardly relative to the aperture 326 for a
distance generally indicated by the dimension 332. The dimension
332 may be considered to be about 1/6 of the outside diameter plate
spring 309. The region 328 is generally in bounded by the dimension
generally indicated by the numeral 330. The dimension 328 is equal
to about 1/6 of the outside diameter of the plate spring 309. As
may be understood by a study of FIG. 31, a portion of the region
328 of the plate spring 309 is borne by the pressure plate 314 and
a portion of the region 329 of the plate spring 309 is borne by the
step washer 308.
[0126] Now referring to FIGS. 32, 34, 35A, 36, 37 and 39A, another
damping valve assembly 52F and associated components will now be
described. The passage 313 formed in the piston 312 allows fluid to
pass from one side of the piston 313 to the other side of the
piston 313 as governed by the action of the damping valve assembly
52F. One or more shims 334 having an aperture are positioned in
stacking relation around the rod 22 and adjacent to the piston 312.
The rod 22 is inserted into the aperture 335 of the step washer 308
in stacking relation so that the step washer 308 is adjacent to the
one or more shims 334. The rod 22 and the step washer 308 are
inserted into the aperture 339 of the pressure plate 314 in sliding
relation so that both the step washer 308 and the pressure plate
314 are adjacent to the one or more shims 334 when a preload force
is applied to the pressure plate to hold it against the one or more
shims 334. The plate spring 309 having an aperture 326 is
positioned in stacking relation around the piston rod 22 and
adjacent to the step washer 308. A plurality of other plate springs
444 may be positioned in stacking relation one to another around
the piston rod and adjacent to the plate spring 309. The retaining
means (not shown) is configured to fixedly hold the other plate
springs 444, plate spring 309, step washer 308, and the one or more
shims 334 in stacking relation to the piston 312.
[0127] The damping valve assembly 52F as shown in FIG. 32 will
respond to control the flow of fluid traveling through the passage
313 as will be illustrated in FIG. 33A, FIG. 33B, FIG. 33C, and
FIG. 33D. In FIG. 33A, the damping valve assembly 52F is
represented as a low volume of fluid (not shown) flows through the
passage 313 in the direction indicated by the arrow 317 as the
piston 312 translates in the direction generally indicated by the
arrow pointed to the numeral 315 at a low speed. Here, the force
generated by the pressure of the fluid flowing through the passage
313 and acting on the shims 334 is sufficient to slightly deflect
the shims 334 a small amount, permitting a limited amount of fluid
to flow through the passage 313. However, the deflection of the
shims 334 is small so the outer edge of the shims 334 do not
substantially act on the pressure plate 314, so that the preload
force acting on the pressure plate 314 holds the pressure plate 314
in a rest position.
[0128] In FIG. 33B, the damping valve assembly 52F is represented
as a medium volume of fluid (not shown) flows through the passage
313 in the direction indicated by the arrow 317 as the piston 312
translates in the direction generally indicated by the arrow
pointed to the numeral 315 at a medium speed. Here, the force
generated by the pressure of the fluid flowing through the passage
313 and acting on the shims 334 is sufficient to deflect the shims
334 a moderate amount, permitting a limited amount of fluid to flow
through the passage 313. Further, the deflection of the shims 334
is sufficient so the outer edge of the shims 334 act on the
pressure plate 314 so as to work against the preload force acting
on the pressure plate 314 causing the pressure plate 334 to
slidingly translate along the step washer 308 from the rest
position in a direction away from the piston 312.
[0129] In FIG. 33C, the damping valve assembly 52F is represented
as a high volume of fluid (not shown) flows through the passage 313
in the direction indicated by the arrow 317 as the piston 312
translates in the direction generally indicated by the arrow
pointed to the numeral 315 at a high speed. Here, the force
generated by the pressure of the fluid flowing through the passage
313 and acting on the shims 334 is sufficient to deflect the shims
334 a substantial amount, permitting a large amount of fluid to
flow through the passage 313. Further, the deflection of the shims
334 is sufficient so the outer edge of the shims 334 act on the
pressure plate 314 so as to overcome the preload force acting on
the pressure plate 314 which causes the pressure plate 334 to
slidingly translate a significant distance along the step washer
308 from the rest position and away from the piston 312.
[0130] As should be apparent to one skilled in the art, and from
studying FIGS. 32, 33A, 33B, and 33C, the arrangement of the
damping valve assembly 52F as shown in FIG. 32 has been shown to
provide an exemplary response which is desirable in controlling the
response in a shock absorber apparatus 10. For example, the shims
334, pressure plate 314, step washer, and combination of plate
springs 309 and 444 may be selected to provide a soft response
characteristic during low speed operation, a firm response
characteristic during medium speed operation and a soft response
characteristic during high speed operation of the shock absorber
apparatus 10. Such a response characteristic of the damping valve
assembly 52F is desirable in some situations where it is desirable
to provide a range of adjustability that can be attained using the
response adjustment mechanism 88 in concert with the damping valve
assembly describe herein.
[0131] Now referring to FIG. 34, a plan view of the step washer 308
is shown having the aperture 335 which is configured to slide over
the outside diameter of the rod 22. The surface 329 of the step
washer 308 is a show in FIG. 35A. The shape of the step washer 308
may be modified to achieve varying desirable results depending on
the type of pressure plate 314 and the type of shock absorber
apparatus 10. The step washer 308 is shown having a thickness
generally indicated by the numeral 310 and has a characteristic
flat surface 329 and an opposite flat surface 331. Now referring to
FIG. 35B, the step washer 308 has a flat surface 329 and a stepped
corner surface 321 joined by a flat surface 331. In the preferred
embodiment, the surface 331 is positioned proximate to the piston
312 in FIGS. 31, 32, 33A, 33B, and 33C. Now referring to FIG. 35C,
another variety of the step washer 308 having a flat surface 329 is
shown with an angle surface 323 joining the flat surface 331 which
is parallel to the surface 329. The surface 331 is positioned
proximate to the piston 312 in the system is shown in FIGS. 31, 32,
33A, 33B, and 33C. Now referring to FIG. 35D, the step washer 308
is shown having a radius corner proximate to the flat surface 331.
In FIGS. 31, 32, 33A, 33B, and 33C, the flat surface 331 would be
positioned proximate to the piston 312.
[0132] Now referring to FIGS. of 36 and 37, the pressure plate 314
of a first variety is shown in further detail. As previously
stated, the pressure plate 314 has an inside diameter 337
configured to be less than the outside diameter 333 of the step
washer 380. The pressure plate 314 further includes ridges or
ledges generally indicated by the numeral 434. Further the pressure
plate 314 also includes valleys generally indicated by the numeral
440. The pressure plate 314 has the ridge or ledge 434 which are
characterized by depth dimension 436. Further, the valley 440 of
the pressure plate 314 is characterized by a depth dimension 442.
From inspection, it is evidence that the dimension 436 is greater
than the dimension 442. Furthermore, the ridge or ledge 434 has a
width dimension generally indicated by the numeral 425.
[0133] Now referring to FIG. it 38A, 38B, 38C, 38D, a cross section
of the step washer 308 surrounded by the pressure plate 314 is
shown. Each pressure plate 314 is shown with a different corner
effect as will be discussed below. The pressure plate 314 has a
flat surface generally indicated by the numeral 432 and the ridge
or ledge of 434 and a second surface substantially opposite of the
first surface generally indicated by the numeral 438. The surface
438 extends in an upward or outward direction from the inner edge
320 (FIG. 39A) forming a radius 433 an reaching an apex at the
ridge or ledge 434. The pressure plate 314 also has an outside
surface 430 which forms a corner transition. Now referring to FIG.
38B, an additional surface 439 having a flat characteristic is
shown. Now referring to FIG. 38C, the pressure plate 314 has a
radius corner 441. Now referring to the 38D, the pressure plate 314
has a step surface generally indicated by the numeral 443. It
should be understood that the examples shown in FIGS. 38 A-D are
representative of some of the corner characteristics that may be
applied to the pressure plate 314 but there are other that may be
considered to fall within the scope of this specification.
[0134] Now referring to FIGS. 39A-C, further variations of pressure
plate 314 are shown in each of the figures. In FIG. 39A, a pressure
plate 314 has a thickness 322 at the inside edge formed by the
aperture 318. The pressure plate 314 has an outer edge as is
indicated generally by the numeral 430 and has an outside diameter
which he is generally indicated by the numeral 316. A series of
ridges or ledges and valleys are shown generally indicated by the
numerals 440 and 434. Now referring to FIG. 39B, another variety of
the pressure plate 314 is shown with alternating ridges and valleys
as generally indicated by the numeral is 434 and 440 respectively.
Now referring to FIG. 39C, yet another variation of the pressure
plate 314 is shown further having alternating ridges and valleys
434 and 440 respectively. It should be understood, that the number
of ridges and valleys in the pressure plate 314 may be changed
without altering the scope of the present invention. The ridge or
ledge of the pressure plate 134 has a radius 433 formed therein
that may be selected to match the natural shape of the plate spring
309 as it is borne by the step washer 308.
[0135] The amount of preload force depends upon many factors
including the thickness and number of plate springs 309 selected,
the difference in thickness between the step washer 308 and the
thickness of the ridge or ledge 434 of the pressure plate 314. The
plate spring 392 may be composed of a flexible spring-steel metal.
The combination of the plate spring 309, step washer 308 and the
pressure plate 314 provide a versatile system for providing
desirable damping characteristics in the shock absorber
apparatus.
[0136] Now referring to FIG. 40, another version of a dampening
valve assembly generally referred to by the designation 52G is
shown in a cross-sectional view. A cylinder 380 defines an inner
bore in which a piston 388 is concentrically attached to a piston
rod 386. A pressure plate 390 is concentrically positioned around
the rod 386, and positioned in stacking relation adjacent to the
piston 388. A plate spring 392 is retained by the pressure plate
390. A helical spring 422 has a first end 424 and an opposite
second end 423. The helical spring 422 is positioned concentrically
around the rod 386. The end 424 of the helical spring 424 is borne
by the plate spring 392 in flexing relation. The end 423 of the
helical spring 422 is borne by a retainer 426. In this arrangement,
the pressure plate 392 is slidingly positioned around the rod 386,
and is configured to allow fluid to flow through the piston 388
through passages (not shown) when the pressure in the fluid flow
acts on the pressure plate in a suitable manner to overcome the
preload force of the plate spring 392 and the helical spring
424.
[0137] Now referring to FIGS. 42, 43, and 44, the pressure plate
390 is shown having a center 396 and an aperture 408. The aperture
408 is configured so that the pressure plate may be positioned
around the rod 386 in sliding relation. The pressure plate 390
includes a base surface 394 and an opposite floor surface 404.
Further, the pressure plate 390 has rim generally indicated by the
numeral 402 extending in a perpendicular direction from the base
surface 394. The distance between the planes of the floor surface
404 in the base surface 394 constitute a thickness dimension
generally indicated by the numeral 406. A plurality of shelves of a
first type 414A and a second type 414B have a first surface 410 an
opposite second surface 412. Each shelf, 414A and 414B, has a width
dimension generally indicated by the numeral 416 and 418
respectively.
[0138] Now referring to FIGS. 41, 45, 46, and 47, the plate spring
392 is shown having an aperture 446 and a flat surface 448. The
plate spring 392 is retained by the pressure plate 390 by arranging
the spring so that a portion of the plate spring 392 is supported
by the top surface 410 of the shelves 414A. The plate spring 392 is
retained by the surface 412 of the shelves 414B. In this
configuration, the plate spring 392 is retained by the pressure
plate 390, and provides a preload force.
[0139] The amount of preload depends largely upon the thickness and
number of plate springs selected for an application. The preload
may also be set by the depth of the step. The Plate spring 392 may
be composed of a flexible spring-steel metal. The combination of
the plate spring 392 and the pressure plate 390 provides a
versatile system that flexes the plate spring 392 in the middle and
with a preload to create firmness.
Operation
[0140] The operation and of the present invention is believed to be
readily apparent and is briefly summarized in the paragraphs which
follow.
[0141] A shock absorber apparatus 10 including a housing 12
including a first end 18 and a second end 14 opposite the first end
18. The housing 12 has a bore 24. A piston 36 is disposed in the
bore 24 proximate the first end 18 and is configured to translate
within the bore 24 responsive to external forces. Another piston 38
is disposed in the bore 24 proximate the second end 14 and is
configured to translate within the bore 24 responsive to external
forces. The piston 36 is coupled to a piston rod 22. The piston rod
22 is partially disposed in the housing 12 proximate the first end
18 and translates into and out of the housing 12. The piston rod 22
includes a mounting element distal from the piston 38 configured to
mount to the wheel of a vehicle. The housing 12 includes a mounting
element 16 proximate the second end 14 and configured to mount to a
vehicle chassis.
[0142] An adjuster or response adjustment mechanism 88 is coupled
to the housing 12 proximate the second end 14 and is configured to
adjust the flow of a damping fluid 370 disposed in the housing 12.
The adjuster or mechanism 88 may include modified biasing members
having large biasing ranges (e.g., 1500-4000 psi). The adjuster or
mechanism 88 can include at least one of a low speed adjustment
portion having elements indicated by the boundary 102 (FIG. 9); a
mid speed adjustment portion having elements indicated by the
boundary 104 (FIG. 9); and a high speed adjustment portion having
elements indicated by the boundary 108 (FIG. 10).
[0143] The low speed adjustment portion can include a needle flow
controller having members 112 and 122 (FIG. 10). The mid speed
adjustment portion can include biasing members 140, 156, and 160
(FIG. 10) configured to control damping fluid flow. The high speed
adjuster portion can include high resistance biasing members 166,
178, and 182 (FIG. 10) configured to control damping fluid flow.
The damping fluid flows through and around the second piston 38 and
first piston 36 and optionally may flow through grooves 356 in the
housing. The cylinder 12 may have grooves 356 formed along the
portion proximate the first piston 36. The grooves 356 enhance the
damping fluid flow around the piston 36. The groove 356 may be
tapered along the length of the cylinder 12 to allow for a varying
groove depth along the length of the groove. The tapered groove can
provide a progressive flow area resulting in a progressive
dampening effect.
[0144] The damping fluid 370 is configured to dampen the
translation of the second piston 38 and first piston 36 within the
bore 24. A damping valve assembly 52E, 52F, or 52G may be coupled
to at least one of the second piston 38 and the first piston
36.
[0145] A bottoming needle or needle assembly 98 is adapted to be
insertable into a bore 66 in the rod 22 and is configured to
control the flow of dampening fluid 370 through or past the piston
38 at a predetermined location in the stroke 342 of the piston 38.
The diameter of the first internal bore may be reduced to
accommodate a reduced second piston 38 size.
[0146] Yet further, the shock absorber apparatus 10 has a first
cylinder 12 defining a first internal bore 24 closed by a first end
wall 18 and an opposite second end wall 14, and has a first port 94
connected in fluid transmission relation to the first internal bore
24. A second cylinder 81 defining a second internal bore 82 closed
by a first end wall 81 and an opposite second end wall 83, and
further comprising a second port 92 connected in fluid transmission
relation to the second internal bore 79. A response adjustment
mechanism 88 is located adjacent to the second cylinder 78, and
connected in fluid transmission relation between the first port 94
and second port 92. The response adjustment mechanism 88 further
comprises three or more adjustment operators 260, 262, and 264
which are operable to direct the fluid flow between the first port
94 and the second port 92.
[0147] The response adjustment mechanism 88 is located in fluid
transmission relation between the first port 94 and the second port
92. The first and second pistons, 36 and 38 respectively, translate
through the internal bore 24 of the first cylinder or housing 12 in
a direction generally indicated by the arrow 344 (FIG. 3), causing
a pressure to develop in the fluid 370 which causes fluid to flow
from port 94 through the passage of 90 and into the response
adjustment mechanism 88 and out to port 92. This direction of flow
is understood as compressive flow when the flow transfers from port
94 to port 92.
[0148] The fluid 94 flowing through the passage 90 encounters the
third base 202 of the response adjustment mechanism 88 and the
second base 182 of the response adjustment mechanism 88. As can
best be understood from inspection of FIG. 10, a fluid may enter
through a bore or plurality of apertures in the plate 236. If this
flow of fluid is characterized as being low in volume resulting
from a low speed motion of the rod 22, the disc 226 remains in the
position shown in FIG. 10 seated against the plate 236. In this low
flow situation, the fluid flows through the concentric bore 224 in
the plate 236 into the bore 190 in the second base 182 and proceeds
through the internal bore 220 of the screw 214 to the stem 112
which has a needle formed on the end 118 which is configured at
least partially enter the bore 220 of the screw 214. Therefore, the
fluid entering the response adjustment mechanism 88 at a low flow
volume may flow out the aperture formed in the shaft 122 as
indicated by the numeral 136 (FIG. 12). As the fluid exits the
aperture 136 of the shaft 122 its flows through an aperture or a
plurality of apertures 199 formed in the housing 198 or
alternatively in an alternate version of the third base 202B (FIG.
22B). The fluid exiting the apertures 199 flows through the port 92
and into the chamber 86 causing the piston 80 to translate within
the second cylinder 78 and compress the compressible fluid
contained in the chamber 84.
[0149] Again referring to FIG. 10, the pressure between the port 94
and the port 92 may be considered at a medium pressure when the rod
22 translates in a direction generally indicated by the arrow 344
(FIG. 3) at a medium speed. At the medium pressure, the preload on
the spring 224 may be selected so that the force generated on the
disc 226 by the medium pressure causes the plate to separate from
the plate 236 as will be discussed further below.
[0150] As pressure from the fluid encounters the plate 236
positioned in the second base 182, some of the pressure will be
transferred to the disc 226 via openings or passages or aperture
formed in the plate 236 and designated as 250, 252, 254 and, in 256
(FIGS. 20, 21). With sufficient pressure to overcome the preload
force of spring 224, as may occur during medium speed events, the
disc 226 will separate from the plate 236, thereby allowing a
greater volume of fluid to flow. After entering the bore 190 and
the cavity 196 of the second base 182, the fluid exerts a pressure
upon the first base 160 by transmitting this pressure through a
passage formed in the cavity 196 of the second base 182 and leading
through the aperture is 183 (FIG. 15) to exert pressure on the
surface of the first base 160. When the pressure upon the first
base 160 is sufficient to overcome that preload force that is
stored by the spring 156, the first base detaches or dislodges from
the second base 182 providing a fluid passage whereby fluid flows
from the cavity 196 of the second base 186 out through the
apertures 183 formed in the of the second base 186, and exits
outwardly through the apertures 199 as previously discussed which
are positioned in fluid communication with the port 92 allowing the
incompressible fluid to flow into the chamber 86 causing the piston
80 to displace and compress the compressible fluid 82 in the
chamber 84.
[0151] The preload force governing the fluid flow when the speed of
the shaft is translating at medium speed in the direction generally
indicated by the arrow 344, is adjusted by turning the internal
hexagonal recess 152 with an Allen wrench as an adjustable means to
modify the preload on the spring 156.
[0152] Yet further, in a situation when the rod 22 is translating
at a high speed in the direction generally indicated by the arrow
344 in FIG. 3, the pistons 36 and 38 work to increase the pressure
of the incompressible fluid proximate to port 94 and through the
passage 90. This increased pressure is propagated to the third base
202 and the second base 182. The pressure generated in the fluid
during a high speed motion of the rod 22, generate a force on the
exposed surface of the second base 182. This force may be
sufficient to dislodge the second base 182 from the third base 202
if the force from the fluid is greater than the preload force
stored in spring 178. When the force of the fluid is sufficient to
overcome the preload force stored in the spring 178, the second
base 182 is dislodged from the third base 202, providing an opening
that forms a new flow passage that is defined by the surface 184 of
the second base 182 and the surface 208 of the third base 202. As
may be seen in FIG. 10, the size of this passage is large compared
to the other passages in the low and medium speed situations, and
allows for a much higher volume a fluid to flow through the
response adjuster mechanism 88.
[0153] The fluid that flows through the passage formed a between
the second base 182 and third base 202 exits through the apertures
199 propagating to the port 92 to enter the chamber 86 which
displaces the piston 80 to further compress the gas contained in
chamber 84. The amount of preload force required to be overcome by
the force generated by the fluid on the second base 182, to provide
the passage between the second base 182 and the third base 202
maybe adjusted by rotating shaft 166 using the wrench flats 264
(FIG. 30) to adjust the longitudinal position of the shaft 166
relative to the third base 202.
[0154] Now considering the situation where the rod 22 travels in a
direction generally indicated by the arrow 347 shown in FIG. 3,
thereby causing a returning travel of the Pistons 36 and 38, a
return flow of incompressible fluid will travel from port 92
through the as response adjustment mechanism 88 and through the
passage 90 through port 94 into the chamber 44. Referring again to
FIG. 10, there are to passages for the returning fluid whose
operation will now be discussed briefly.
[0155] A first passage is notes as the fluid travels from port 92
having a low pressure, the fluid may travel through the apertures
199 into the aperture 136 of the shaft 122 to encounter the stem
112 and the needle portion thereof of the end 118 (FIG. 11). Then
depending on the location of the needle portion 118 relative to the
bore 220 of the screw 214, a fluid of low pressure will flow
through the bore 220 through the screw 214 into the cavity of the
second base 182 through the aperture formed in the disc 226 and
through the concentric aperture of the plate 236 generally
indicated by the numeral 244. The fluid is then the able to travel
through the passage 90 to the port 94 and into the chamber 44.
[0156] Another fluid passage through the response adjustment
mechanism 88 allows fluid to flow from port 92 through passage 90
to port 94 will now be discussed. In this situation, the apertures
201 formed in the third base 202 connect to internal channels or
passages which are connected to the aperture 205 (FIG. 24). The
fluid flowing from the apertures 205 in the third base 202 may
generate a pressure against a washer 266 which is shown in a
position blocking the flow from the apertures 205. When the
pressure exerted by the fluid contained in the apertures 205 is
sufficient to overcome the preload pressure stored by the spring
268, the washer 266 becomes dislodged from the surface 212 of the
third base 202 allowing fluid to flow out of the apertures 205 out
to the passage 90 to port 94 which is connected to the chamber
44.
[0157] Yet further, the shock absorber apparatus 10, has a first
cylinder 12 defining a first internal bore 24 has an internal
diameter 277, and closed by a first end wall 18, and is further
closed by an opposite second end wall 14, and further has a first
port 94 connected in fluid transmission relation to the first
internal bore 24. A rod 22 has a first end 73 and an opposite
second end 64, and wherein the rod 22 movably extends into the
first internal bore 24 through an aperture 23 formed in the first
end wall 18 so that the second end 64 of the rod is positioned
concentrically within the first internal bore 24, and so that the
first end of the rod 73 is positioned outside the first internal
bore 24. A first piston 36 is fixedly attached to the rod 22 at an
intermediate position located between the first and the second end,
73 and 64 respectively, of the rod 22, and positioned
concentrically within the first cylinder 12. A second piston 38 is
fixedly attached to the rod 22 proximate to the second end 64 of
the rod 22, and is positioned concentrically within the first
cylinder 12. A second cylinder 78 defines a second internal bore 79
closed by a first end wall 81 and an opposite second end wall 83,
and further has a second port 92 connected in fluid transmission
relation to the second internal bore 79. A response adjustment
mechanism 88 is located adjacent to the second cylinder 78, and is
connected in fluid transmission relation between the first cylinder
port 94 and the second cylinder port 92, and wherein the response
adjustment mechanism 88 is configured to provide three or more
adjustments 260, 262, and 264 for tuning the response of the shock
absorber system 10.
[0158] Furthermore, a shock absorber apparatus 10, has a housing 12
comprising a first internal bore 345 having a diameter 348, and
includes a second internal bore 346 having a diameter 350. The
housing 12 is closed by a first end wall 354, and further closed by
an opposite second end wall 353. A rod 22 has a first end 73 and an
opposite second end 64, and wherein the rod movably extends into
the first and/or second internal bore 345 and 346 respectively,
through an 356 aperture formed in the first end wall 354 so that
the second end 64 of the rod 22 is positioned concentrically within
the first internal bore 345 or second internal bore 346, so that
the first end 73 of the rod 22 is positioned outside the housing
12. A first piston 36 having a diameter 274 is fixedly attached to
the rod 22 at an intermediate position located between the first
end 73 and the second end 64 of the rod 22, and is positioned
within the first internal bore 345 in sliding relation. A second
piston 38, having a diameter 279 is fixedly attached to the rod 22
proximate to the second end 64 of the rod 22, and positioned within
the first and/or the second internal bore 345 and 346 respectively,
in sliding relation. The diameter 274 of the first piston 36 is
approximately equal to the diameter 348 of the first internal bore
345, and the diameter 279 of the second piston 38 is approximately
equal to the diameter 350 of the second internal bore 346. In
addition, the diameter 279 of the second piston 38 is less than the
diameter 274 of the first piston 36.
[0159] Yet further, the piston rod 22 has a longitudinal axis, and
an external surface, and a bore 66 formed concentrically therein.
The piston rod 22 has one or more of apertures 366 formed within
the piston rod 22 and extending from the external surface of the
piston rod 22 into the bore 66 of the piston rod 22 to form a fluid
passage. The first piston 36 is configured to translate within the
first cylinder bore 345 in response to an external force; a second
piston 38 is configured to translate within the first cylinder bore
345, and in the second cylinder bore 346, and in response to the
external force. A needle assembly 96 is configured to enter the
bore 66 of the piston rod 22 as the second piston 38 nears the
second cylinder bore 346.
[0160] Yet further, the shock absorber apparatus 10, has a housing
10, and a cylinder bore 24 enclosed by the housing, and further has
a longitudinal axis 272. A rod 22 is substantially positioned
concentric to, and along, the longitudinal axis 272 of the cylinder
bore 24, and is partially positioned within the cylinder bore 24. A
piston 388 is fastened to the rod 22, and is slidingly positioned
within the cylinder bore 24. A pressure plate 390 is slidingly
positioned on the rod 22, and is positioned adjacent to the piston
388. Wherein, the plate spring 392 is retainingly mounted to the
pressure plate 390.
[0161] And still further, the invention includes, a shock absorber
apparatus 10 a cylinder bore 24 enclosed by the housing 12, and
having a longitudinal axis 272. A rod 22 having a first end 64 and
an opposite second end 73, and wherein the rod 22 is substantially
positioned concentric to, and along, the longitudinal axis 272 of
the cylinder bore 24, and wherein the first end 64 of the rod 22 is
positioned within the cylinder bore 24. A piston 312 is fastened to
the rod 22 in stacking relation, and positioned within the cylinder
bore 24. A step washer 308 has a first thickness dimension 310, and
is positioned on the rod 22 in stacking relation, and positioned
proximate to the piston 312. A pressure plate 314 has an outside
diameter 316, and has an aperture 339 formed therein, and wherein
the pressure plate 314 has an inner edge 320 bounded by the
aperture 339, and wherein the inner edge 320 has a second thickness
dimension 322, and wherein the pressure plate 314 is positioned
around the step washer 308 in sliding relation so that the step
washer extends through the aperture 339 of the pressure plate 314.
A plate spring 309 has an outer edge 311, and has an aperture 326
formed therein. The plate spring 309 has a first region 328 bounded
by the outer edge 311 of the plate spring 309 and extends inwardly
by a first distance 330. The plate spring 309 has a second region
329 bounded by the aperture 326 and extends outwardly by a second
332. In operation, a portion of the outer region 328 of the plate
spring 309 is borne by the pressure plate 314, and further a
portion of the inner region 329 of the plate spring 309 is borne by
the step washer 308. In this case, the first thickness dimension
310 is greater than the second thickness dimension 322. Also, the
first distance 330 and the second distance 332 are less than the
outside diameter 316 of the pressure plate 314 divided by 6.
[0162] In compliance with the statute, the invention has been
described in language more or less specific as to structural and
methodical features. It is to be understood, however, that the
invention is not limited to the specific features shown and
described, since the means herein disclosed comprise preferred
forms of putting the invention into effect. The invention is,
therefore, claimed in any of its forms or modifications within the
proper scope of the appended claims appropriately interpreted in
accordance with the doctrine of equivalents.
* * * * *