U.S. patent application number 11/143490 was filed with the patent office on 2005-11-10 for pedalling machines including scooters and driving mechanisms therefor.
Invention is credited to Hung, George Hon-Cheung.
Application Number | 20050248117 11/143490 |
Document ID | / |
Family ID | 28052856 |
Filed Date | 2005-11-10 |
United States Patent
Application |
20050248117 |
Kind Code |
A1 |
Hung, George Hon-Cheung |
November 10, 2005 |
Pedalling machines including scooters and driving mechanisms
therefor
Abstract
This invention relates to a drive mechanism for a scooter or
similar vehicle. A pair of opposed rotatable crank arms are mounted
to a drive gear on the frame. Each crank arm is attached to a
footboard that is itself rotatably mounted to the frame. The
footboard is mounted further from the axis of the crank arms than
the distance from the axis of the crank arms to the point at which
they contact the footboards. Reciprocating downward pressure on
each footboard drives rotation of the crank arms which in turn
drive a wheel of the vehicle.
Inventors: |
Hung, George Hon-Cheung;
(Hong Kong, HK) |
Correspondence
Address: |
BUCHANAN INGERSOLL PC
(INCLUDING BURNS, DOANE, SWECKER & MATHIS)
POST OFFICE BOX 1404
ALEXANDRIA
VA
22313-1404
US
|
Family ID: |
28052856 |
Appl. No.: |
11/143490 |
Filed: |
June 3, 2005 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
11143490 |
Jun 3, 2005 |
|
|
|
10864389 |
Jun 10, 2004 |
|
|
|
10864389 |
Jun 10, 2004 |
|
|
|
10259387 |
Sep 30, 2002 |
|
|
|
6764088 |
|
|
|
|
Current U.S.
Class: |
280/221 ;
280/259 |
Current CPC
Class: |
B62M 1/26 20130101; B62K
3/002 20130101 |
Class at
Publication: |
280/221 ;
280/259 |
International
Class: |
B62M 001/00 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 11, 2002 |
HK |
02102751.3 |
Claims
1. A pedalling machine including: a main housing, a pair of
co-axially rotable crank members, each of said crank members
including a first arm portion extending generally radially from the
axis of rotation of said crank members ("said Axis of Rotation")
and a second arm portion extending substantially parallel to said
Axis of Rotation from the distal end of said first arm portion,
wherein said first arm portions of said crank members being
disposed oppositely and diametrically about said Axis of Rotation,
and a pair of pivotally movable footboards both extending from the
same side of said Axis of Rotation towards said crank members, each
distal end of said footboard being in driving engagement
relationship with said second arm portion of the corresponding
crank member so that each downward pivotal angular movement of said
footboard will bring about movement of said correspond crank member
in the same angular direction.
2. A machine of claim 1, wherein the length of each said footboard
is longer than the distance between the pivotal axis of said
footboard and said Axis of Rotation.
3. A machine of claim 1, further including a drive wheel which is
co-axially rotatable with and mounted between said pair of crank
members for driving engagement by said crank members.
4. A machine of claim 3, wherein said drive wheel is connected to a
load via an endless power transmission link.
5. A machine of claim 4, wherein said power transmission link is a
chain or belt surrounding said drive wheel and the load is a driven
wheel.
6. A machine of claim 5, wherein the diameter of said driven wheel
is substantially larger than the diametric length of said first arm
portions of said crank members.
7. A machine of claim 5, further including a second driven wheel
not connected to said crank members via an endless power
transmission link.
8. A machine of claim 7, wherein each said footboard includes a
downwardly dependent member which supports the machine in a tilted
upright posture when the second arm portion of the corresponding
crank member is at its lowest point in its rotation about said Axis
of Rotation.
9. A machine of claim 10, wherein the divergent angle between said
pair of footboards is about extend 36.degree..
10. A drive mechanism for a vehicle having at least one front and
one rear wheel comprising: a pair of co-axle opposed rotatable
craned-arms to directly or indirectly drive a wheel of said
vehicle; a pair of rotatably mounted footboards mounted on said
vehicle and wherein said footboards are engaged at or adjacent an
outer end of said craned-arms such that downward pressure on one
footboard may cause downward rotation of the connected craned-arm;
and wherein the distance between the axles of rotation of the
footboards and the axles of rotation of the craned-arms is
substantially greater than the distance from the centre of rotation
of the craned-arms to the point of connection with said
footboards.
11. A drive mechanism for a vehicle having at least one front and
one rear wheel as claimed in claim 1 wherein a drive gear is
co-axially mounted with said crank arms to be rotated by rotation
of said crank arms.
12. A drive mechanism for a vehicle having at least one front and
one rear wheel as claimed in claim 2 said drive gear is connected
with an axle of a driven wheel to drive rotation of the wheel of
the vehicle.
13. A drive mechanism for a vehicle having at least one front and
one rear wheel as claimed in claim 3 wherein said connection to
said drive wheel comprises a chain connecting said drive gear with
a gear co-axially mounted to said driven wheel.
14. A drive mechanism for a vehicle having at least one front and
one rear wheel as claimed in claim 1 wherein said interconnection
between said crank arms and said footboards allows movement of the
point of connection in the radial direction of extension of the
footboards while being substantially fixed in a transverse
direction.
15. A drive mechanism for a vehicle having at least one front and
one rear wheel as claimed in claim 1 wherein said vehicle comprises
a scooter or bicycle.
16. A drive mechanism for a vehicle having at least one front and
one rear wheel as claimed in claim 1 wherein said vehicle comprises
a bicycle.
17. A vehicle including: A pair of wheels interconnected by a
frame. A drive wheel located intermediate between the axles of said
pair of wheels, said drive wheel includes a pair of crank members
radially extending from said axle of said drive wheel, each said
crank member includes a connecting arm at its distal end which is
substantially parallel to said axle of said drive wheel, said pair
of crank members being separated by the plane of rotation of said
drive wheel. A transmission link connecting said drive wheel to
drive at least one of said pair of wheels. A pair of footboards
separated by the plane of rotation of said drive wheel, each said
footboard being pivotable about an axle substantially parallel to
the axle of said drive wheel, said connecting arm of said crank
member being slidable along at least a portion of the footboard on
the same side of said drive wheel, said footboard and said
connecting arm being disposed so that downward pivotal movements of
said footboard cause sliding and rotation of said connecting arm in
a direction to drive said vehicle.
18. A vehicle of claim 8, wherein one of said pair of wheels is
pivotally movable about an axle which is substantially orthogonal
to the axle of said wheel for steering.
19. A vehicle of claim 9, wherein said pairs of footboards and said
pair of connecting arms are in alternate driving engagement
relationship so that when a connecting arm on one side of said
drive wheel is being downwardly driven by a footboard, the
footboard on the other side of said drive wheel will be upwardly
driven to prepare for the next driving engagement.
20. A vehicle of claim 17, wherein said transmission link
connecting said drive wheel to said at least one of said pair of
wheels includes a mechanism to convert a counter-clockwise rotation
of the drive wheel into clockwise rotation of said wheel.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to pedalling machines, such as
scooters, stepping exercise machines and other wheeled machines
such as bicycles, tricycles and the like.
[0002] This invention also relates to drive arrangements or
mechanisms for, in particular, although not necessarily solely,
pedalling machines or vehicles similar in form to conventional
scooters. The invention may, in some aspects, also apply to
bicycles or other similar land-based pedal craft.
BACKGROUND TO THE INVENTION
[0003] Pedalling machines such as stepper or stepping exercise
machines are found in many fitness centres. It is desirable that
such stepping exercise machines can be configured to combine in
synergy the effects of stepping machines and spinning machines
which are generally similar to exercise bicycles.
[0004] Vehicles such as scooters have existed for a considerable
period of time. Throughout that period, the general form of the
scooter varied little from the standard construction of a
two-wheeled vehicle, a footboard on which a user may stand
intermediate of the front and rear wheels and an upright post with
handles for steering attached directly to and over the front
wheel.
[0005] The varied named scooter may well be derived from its
conventional driving system of a user standing with one foot on the
scooter and the other being used to push the vehicle along its
path. To some extent, a drive mechanism for a scooter is
inconsistent with the term for the vehicle itself, however, it is
to be appreciated that the term "scooter" generally applies to
vehicles of that basic overall construction.
[0006] In providing drive mechanisms for scooters, conventional
techniques such as motorized power have been applied. However,
considerable difficulty has been experienced in generating any form
of pedal-based system for use in scooters.
[0007] For example, scooters usually have a low clearance to ground
and conventional rotationally based-pedal and craned-mechanisms
need to rely on a relatively short-craned length from the centre of
drive rotation to the pedal. Trying to generate sufficient power
from a cyclic motion in which the radius of the path of the pedal
is small is quite difficult. It is substantially more difficult
when provided on an item having no conventional seat on which a
user may reside.
[0008] Indeed, to a large extent, cyclic motion of pedals is
difficult without a seat and although this may be performed for a
short period on bicycles where the craned length is substantially
greater, even on bicycles it is difficult to maintain this for long
periods of time.
[0009] For these reasons, an alternative manual drive mechanism may
be desirable.
OBJECT OF THE INVENTION
[0010] It is an object of this invention to provide drive
arrangement for pedalling machines such as stepping machines and
vehicles such as scooters that may overcome some of the
disadvantages of the prior art or at least provide users with a
useful choice.
SUMMARY OF THE INVENTION
[0011] Accordingly, in a first aspect, the invention may broadly be
said to consist in a drive mechanism for a vehicle having at least
one front and one rear wheel comprising:
[0012] a pair of co-axle opposed rotatable crank arms to directly
or indirectly drive a wheel of said vehicle;
[0013] a pair of rotatably mounted footboards mounted on said
vehicle and wherein said footboards are engaged at or adjacent an
outer end of said crank arms such that downward pressure on one
footboard may cause downward rotation of the connected crank arm;
and
[0014] wherein the distance between the axis of rotation of the
footboards and the axis of rotation of the crank arms is
substantially greater than the distance from the centre of rotation
of the crank arms to the point of connection with said
footboards.
[0015] Preferably a drive gear is co-axially mounted with said
crank arms to be rotated by rotation of said crank arms.
[0016] Preferably said drive gear is connected with an axle of a
driven wheel to drive rotation of the wheel of the vehicle.
[0017] Preferably said connection to said drive wheel comprises a
chain connecting said drive gear with a gear co-axially mounted to
said driven wheel.
[0018] Preferably said interconnection between said crank arms and
said footboards allow movement of the point of connection in the
radial direction of extension of the footboards while being
substantially fixed in a transverse direction.
[0019] In a second aspect of the present invention, there is
provided a pedalling machine including:
[0020] a main housing,
[0021] a pair of co-axially rotable crank members, each of said
crank members including a first arm portion extending generally
radially from the axis of rotation of said crank members ("said
Axis of Rotation") and a second arm portion extending substantially
parallel to said Axis of Rotation from the distal end of said first
arm portion, wherein said first arm portions of said crank members
being disposed oppositely and diametrically about said Axis of
Rotation, and
[0022] a pair of pivotally movable footboards both extending from
the same side of said Axis of Rotation towards said crank members,
each distal end of said footboard being in driving engagement
relationship with said second arm portion of the corresponding
crank member so that each downward pivotal angular movement of said
footboard will bring about movement of said correspond crank member
in the same angular direction.
[0023] Preferably, the length of each said footboard is longer than
the distance between the pivotal axis of said footboard and said
Axis of Rotation.
[0024] Preferably, said machine further including a drive wheel
which is co-axially rotatable with and mounted between said pair of
crank members for driving engagement by said crank members.
[0025] Preferably, said footboard includes a downwardly dependent
member which supports the machine in a tilted upright posture when
the second arm portion of the corresponding crank member is at its
lowest point in its rotation about said Axis of Rotation.
[0026] Preferably, the divergent angle between said pair of
footboards is about 36.degree..
[0027] According to another aspect of the present invention, there
is provided a vehicle including:
[0028] A pair of wheels interconnected by a frame.
[0029] A drive wheel located intermediate between the axles of said
pair of wheels, said drive wheel includes a pair of crank members
radially extending from said axle of said drive wheel, each said
crank member includes a connecting arm at its distal end which is
substantially parallel to said axle of said drive wheel, said pair
of crank members being separated by the plane of rotation of said
drive wheel.
[0030] A transmission link connecting said drive wheel to drive at
least one of said pair of wheels.
[0031] A pair of footboards separated by the plane of rotation of
said drive wheel, each said footboard being pivotable about an axle
substantially parallel to the axle of said drive wheel, said
connecting arm of said crank member being slidable along at least a
portion of the footboard on the same side of said drive wheel, said
footboard and said connecting arm being disposed so that downward
pivotal movements of said footboard cause sliding and rotation of
said connecting arm in a direction to drive said vehicle.
[0032] Preferably, one of said pair of wheels is pivotally movable
about an axle which is substantially orthogonal to the axle of said
wheel for steering.
[0033] Preferably, said pairs of footboards and said pair of
connecting arms are in alternate driving engagement relationship so
that when a connecting arm on one side of said drive wheel is being
downwardly driven by a footboard, the footboard on the other side
of said drive wheel will be upwardly driven to prepare for the next
driving engagement.
[0034] Preferably, said transmission link connecting said drive
wheel to said at least one of said pairs of wheels includes a
mechanism to convert a counter-clockwise rotation of the drive
wheel into clockwise rotation of said wheel.
[0035] Other aspects of the invention will become apparent to those
skilled in the art to which the invention relates upon reading the
following description and the preferred embodiments disclosed
therein.
BRIEF DESCRIPTION OF THE DRAWINGS
[0036] Preferred embodiments of the invention will now be described
with reference to the following drawings in which:
[0037] FIG. 1 shows a perspective view of a scooter in accordance
with one embodiment of the invention;
[0038] FIG. 2 shows a perspective underside view of a portion of
the embodiment of FIG. 1;
[0039] FIG. 3 shows a side view of embodiment of FIG. 1 with the
left footboard at bottom dead center and the right footboard having
passed the top dead center;
[0040] FIG. 4 shows a side view of embodiment of FIG. 1 with the
right footboard at bottom dead center and the left footboard having
passed the top dead center;
[0041] FIG. 5 shows a perspective view of a scooter in accordance
with a further embodiment of the invention;
[0042] FIG. 6 shows a perspective view of a bicycle in accordance
with a yet further embodiment of the invention;
[0043] FIG. 7 shows a prospective view of a scooter in accordance
with a yet another further embodiment of the invention;
[0044] FIG. 8 shows a partly disassembled prospective view of the
scooter of FIG. 7,
[0045] FIG. 9 shows a side view of the scooter of FIG. 7, and
[0046] FIG. 10 shows a perspective view of the scooter of FIG. 7
while being supported on a single footboard.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0047] Referring to the drawings, various embodiments of the
invention are described. Throughout the description, reference is
made to scooters and bicycles with the majority of the description
being given in relation to scooters specifically. It will be
appreciated on reading the various embodiments that many aspects
described may equally apply to stepping machines and other machines
or vehicles and although those described are usually provided as
two wheeled vehicles, other wheel or non-wheel arrangements may
also apply. For example, the basic scooter can easily be provided
with a tandem rear wheel or by connecting the drive wheel to a
resistance load without making any departure from the aspects of
the invention itself.
[0048] The term scooter is generally used in the specification to
describe a usually two wheeled vehicle having a body portion on
which a user may stand and an upstanding steering column yet no
seat or seat post.
[0049] Referring to FIGS. 1 and 2, one embodiment of the invention
is shown in the form of a scooter 1 having a main housing or
central frame 2, which in this embodiment, acts to support
connections for rotatable front 3 and rear 4 driven wheels.
[0050] Unlike convention scooters that rely solely on pushing of
the vehicle by the user, this scooter also incorporates a drive
mechanism 5.
[0051] This particular drive mechanism is constructed to drive the
rear driven wheel 4. It will be apparent that the various
embodiments described may be reversed where possible to drive the
front driven wheel instead. However, due to the front wheel 3 being
used for steering in most such scooters, it is preferred to drive
the rear driven wheel as this may simplify the mechanism 5.
[0052] The drive mechanism 5 of this embodiment includes a pair of
crank members 6 and 7, rotatably mounted to the frame 2. Each crank
member includes a first crank arm portion and a second crank arm
portion. The first arm portion extends radially from the axle 8 and
the second arm portion 11, 12 extends generally transversal to the
first arm portion and parallel to the axle 8 at the distal end of
the first arm portion. Here, the distal end refers to the end of
the first arm portion away from the axle 8. Typically the crank
members 6 and 7 will be co-axially mounted to further simplify the
mechanism 5. Each crank member 6, 7 is mounted to rotate about an
axis of rotation about the axle 8 through or connected to the frame
2 at an inner end 9, 10 while an outer end or the second crank arm
11, 12 transcribes a circle about the axle 8.
[0053] The crank members 6, 7 are themselves connected to a driving
gear wheel 14 which in turn is operatively connected to a driven
wheel, being in this case, the rear wheel 4. This is in accordance
with a conventional bicycle arrangement for translating rotational
motion of crank arms into drive of a wheel. The operative
connection in a case such as this may use a chain 15 or an endless
belt and an optional driven gear 16 fixed rotationally with the
driven wheel to cause some form of corresponding rotation.
Typically this would involve mounting the gear 16 co-axially with
the driven wheel 4 on its axle 17. Other bicycle technology or
similar has included variations on these methods such as replacing
the chain with a rotating drive shaft, etc. These alternatives
exist to suit particular applications and can be adopted as
necessary into the current mechanism 5.
[0054] The scooter 1 uses two footboards 18, 19 to drive rotation
of the crank members 6 and 7 respectively. Through the remainder of
the mechanism, this in turn rotates the rear driven wheel 4.
[0055] The footboards 18, 19 are rotatably mounted to the frame 2
at or adjacent one end of the board and connected to the crank
members. The pivotal joints of the footboards in this embodiment
are intermediate between the axles of the rear driven wheel 4 and
the driving gear wheel 14, although the pivotal joints may be
located further away from the gear wheel 14. Each footboard 18, 19
can apply downward pressure to a respective crank member 6, 7. To
accommodate rotation of the crank arms, lateral movement of the
point of connection along the footboard is necessary.
[0056] Referring to FIG. 2, the connection between each footboard
and associated crank arm can be seen. In this particular
embodiment, rollers 21, 22 on the end of the crank arms contact an
underside of each of the footboards. As each footboard is depressed
as will be explained later, the associated crank arm may rotate
downwards with the footboard and the roller connection allows
movement in the radial direction of the footboard from its
axis.
[0057] Although not critical, it is also preferred to place some
form of retention means under the rollers to avoid complete
disassociation of the footboards form the rollers. In this
embodiment a channel section is provided to trap the rollers with
lower flanges 23, 24 keeping the rollers in contact.
[0058] Generally, numerous alternative forms of sliding connection
between the footboard and the crank arm could be provided however,
it should be noted that reduction of friction in the connection is
preferred to reduce drag in the drive mechanism as a whole.
[0059] As shown in FIG. 2, as the footboard 19 is depressed, the
roller 22 will move along the footboard 19, initially towards its
outer end, as the crank member 7 is rotated. By fixing the other
crank member 6 to the rotation of crank member 7, the crank member
6 is driven up by this process and from the position shown in FIG.
2, will initially move up and inwards along the footboard 18, hence
lifting the footboard 18 for the next depression of that board.
[0060] It can be seen that, in use, a rider may alternately depress
the footboards in a manner not unlike those provided in stepper
machines in gymnasiums. Alternate weigh transfers between each of
the boards continues the rotation.
[0061] Referring again to FIG. 1, it can be seen that connecting
axles 25, 26 provide the axis of rotation of the footboards 18, 19
with respect to the frame 2. Although it is not essential that
these axles are substantially co-axial connections, it is
preferred.
[0062] It should be noted that the axis of rotation of the
footboards is placed substantially further away from the centre of
rotation of the cranks than the radial length of those crank
members. In doing so, the angle that the footboards must rotate is
reduced to improve the riders stability on the scooter.
[0063] Referring to both FIGS. 3 and 4, it can be seen that the
left and right cranks are respectively at their bottom dead centre
positions with respect to the corresponding footboards.
[0064] At this moment, the upper crank member has passed the top
dead centre position relative to the footboard and, as will be
appreciated, drive will continue to be imparted to rotate the
instantaneous upper crank member clockwisely and advance it towards
the bottom dead centre. Thus, the instantaneous upper crank member
will continue to receive drive until the first crank arm portion is
transverse to the angle of the footboard. As shown in FIG. 3, the
left footboard 19 has reached its bottom dead centre position with
the footboard 19 and the first arm portion of the crank member 7 at
right angles to each other. In this position, it can clearly be
seen that the crank arm 6 has progressed beyond its own highest
vertical upwards position (which has already passed its top dead
centre) and is ready to be rotated downwards while driving the
opposed crank member 7 upwards.
[0065] FIG. 4 shows the other extreme when the right footboard 18
is at its bottom dead centre at which moment the footboard 18 and
the first radial crank arm portion of the crank member 6 at right
angles to each other. It will be noted that, at this instance, the
footboard 19 has passed the top dead centre and the tangential
component of the pedalling force acting by the footboard on the
crank member 7 will bring about downward movement of the crank
member 7 if sufficient driving force is applied. The phrases "top
dead centre" and "bottom dead centre" in the present context mean
the configuration at which the first crank arm portion is generally
at right angles to the footboard so that there is generally no
tangential component of the force acting by the footboard on the
first crank arm portion of the corresponding crank arm 7.
[0066] Referring generally to FIG. 5 and 6, an alternative
embodiment is shown whereby the footboards 18, 19 have been
replaced by extending arms 28, 29 connected to pedals 30, 31. The
arrangement is much the same as the previous embodiment and
operates in the same manner. It is simply a matter of choice as to
which a user or manufacturer may prefer.
[0067] The previous embodiments have all used a steering column 33
extended from the front wheel in a generally upright fashion.
Typically this is attached to the front wheel by the use of forks,
34. A rotational connection to the frame 2 allows the front wheel
to be turned independently to turn the scooter.
[0068] In FIG. 6, the same drive mechanism is applied to a bicycle.
The only principal difference aside from the usual increase in
diameter of the wheels of the vehicle is the inclusion of a seat
post 37 and seat 38. Otherwise, the arrangement and operation is
the same as described for the scooter.
[0069] It will be appreciated that the mechanism may be especially
suited to a scooter as the reciprocating motion of the footboards
may be easier to use when a particularly short crank arm is
provided. To obtain clearance between the ground and the crank,
such a short arm is necessary for a vehicle having wheels of
smaller diameter than those of a conventional bicycle. Although
small children can use conventional bicycles having small wheel
diameters, they are uncomfortable for adults to utilise as the
rotation movement of the knees is confined over a short range of
movement in completion of an entire circle of motion. In contrast,
the reciprocating motion of this scooter is easy to use for both
adult and children.
[0070] In the scooter arrangements, more recent additions to such
apparatus such as brakes and foldable frames have been provided. A
folding joint is provided in FIG. 1 as shown. Similarly, brakes and
the like could be incorporated if desired. However, if the driven
wheel such as the rear wheel 4 is provided with no forward
freewheeling, such that rotation of the wheel is always associated
with rotation of the cranks, braking can be applied by resisting
movement of the footboards. This is achieved by placing weight on
the rising footboard rather than driving a footboard further down
to go forward.
[0071] Referring to FIGS. 7 to 10, there is shown a scooter
incorporating yet another further embodiment of the present
invention of a drive mechanism. The scooter 1 is generally similar
to the scooter of FIG. 1 and includes a frame 2 interconnecting a
front wheel 3 and a rear wheel 4. A drive or gear wheel 14 is
provided on the frame 2 at a location intermediate between the
axles of the front 3 and rear 4 wheels.
[0072] The drive or driving wheel 14 includes a pair of crank
members each having a first crank arm 60, 70 radially extending
from the axle 8 of the drive wheel 14. A second crank arm or a
connecting arm 61, 71 which is substantially parallel to the axle 8
of the drive wheel, is provided at the distal end of each of the
crank members 6 and 7 (or, in other words, the distal end of each
of the first crank arms 60, 70) and extends away from the drive
wheel. The drive or gear wheel 14 is connected to the rear wheel 4
via a transmission link which is an endless slotted chain in the
present specific example. Of course, a driving belt may also be
utilized with appropriate modifications.
[0073] Similar to the scooter of FIG. 1, a pair of footboards 18,
19 are pivotally mounted on the frame and are disposed on the two
sides of the frame 2 or drive wheel 14. Unlike the embodiment of
FIG. 1 in which the pivotal axles of the footboard are located
intermediate between the drive wheel 14 and the rear wheel 4, the
pivotal axles of the footboards 18, 19 of the present embodiment
are mounted intermediate between the drive wheel 14 and the front
wheel 3.
[0074] Each of the footboard 18, 19 includes a plank surface on the
underside on which the connecting arm or the second crank arm
portion 61, 71 of a crank member can slide while the crank member
is undergoing rotational motions. The footboard, particularly the
plank surface, is arranged in a driving engagement with the
connecting arm of the crank member so that when the connecting arm
is elevated above the axle 8 of the drive wheel, downward movements
of the footboard will cause the connection arm to slide with
respect to the plank surface and to rotate in a direction to drive
the rear or driven wheel. At the same time, it would be noted that
the pairs of footboard and crank member are in alternate driving
engagement relationship. For example, when one footboard is driving
the corresponding crank member downwards, the other footboard is
being pivotally moved upwards by the other corresponding crank
member to prepare for the next downward driving of the crank member
in contact with it.
[0075] The footboard 18, 19 further includes a downwardly dependent
member which provides a screen to keep the end of the connecting
arm (or the second arm portion) away from the outside to prevent
external matters, such as ends of trousers, from being caught. This
downward dependent member also supports the scooter in the tilted
upright position as shown in FIG. 10.
[0076] In the present embodiment, it will be seen that when the
footboard drives the crank member downwardly, the drive wheel will
be driven anti-clockwisely. To ensure that this counter-clockwise
rotation is translated into a clockwise rotation of the rear wheel
in order to forwardly drive the scooter, a simple wheel-drive
mechanism 90 is incorporated on the rear wheel so that the slotted
chain will pass the upper part of the toothed wheel attached to the
rear wheel instead of engaging with the lower half of the toothed
wheel as in FIG. 3. By this arrangement, counter-clockwise rotation
of the drive wheel will bring about clockwise movement of the rear
wheel and therefore provides forward drive to the rear wheel.
[0077] To provide an efficient or effective machine drive mechanism
while still comfortably accommodating a user's feet, it is highly
preferable that the inclination of the footboard with respect to
the horizontal plan is about 18.degree.. For the present example,
the distance between the crank axle and the footboard pivotal axle
is considerably larger than the effective length of the crank
members, i.e., the length of the first crank arm portion, for a
useful machine ratio. In the present specific example, the distance
between the crank and footboard axle is about 270 cm and the
effective length of first crank arm portion is about 75 cm.
[0078] Thus, it has been described in the various embodiments above
drive mechanisms or arrangements which convert substantially
rectilinear motions (i.e., vertical movements of the feet of a
user) to circular motions of the cranks and the driving wheels.
Furthermore, it will be noted with a shorter distance between the
axles of the footboard and the crank members, a longer pair of
crank arms will result in a greater maximum angular distance
between the two footboards. With this arrangement, when one
footboard is at the bottom dead center, the other footboard will
have well passed its top dead center and downward pressure of that
footboards will produce easier or more efficient downward movements
of the footboard towards the bottom dead center.
[0079] Thus it can be seen that an alternative drive mechanism and
a vehicle with such a mechanism is provided that may have
advantages over the conventional rotational movement of pedals,
especially when applied to scooters. It may also provide an
alternative form of exercise to users rather than the conventional
bicycle.
[0080] The invention has been described with reference to a number
of embodiments but should not be considered restricted to those
particular embodiments. Specific integers referred to throughout
the description are deemed to incorporate known equivalents where
appropriate. In particular, while wheeled vehicles in the form of
scooters have been described, it will be understood that the drive
mechanisms can be easily adapted to other wheeled or non-wheeled
machines such as stepping exercisers or other stationery set-ups
without loss of generality.
* * * * *