Note: Descriptions are shown in the official language in which they were submitted.
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PORTABLE ADJUSTABLE MOTORCYCLE PROP JACK
The invention relates to an apparatus for lifting motorcycles. More
particularly, the invention relates to apparatus especially adapted for
raising a
motorcycle's rear wheel.
BACKGROUND INFORMATION AND PRIOR ART:
Motorcycles are not always delivered from the manufacturer with a
centre stand that lifts the rear and/or front wheel off the ground. Typically
motorcycles are delivered with a side stand that operates by canting the
motorcycle
slightly to the left and held against leftward toppling by the cantilevered
and
pivotable ground biasing side stand. While the motorcycle is in the above
position
and resting on its sidestand, it is also resting on its front and rear tires
not allowing
the rear wheel to spin freely as it is locked by the contact with the ground.
Commonly, motorcycles require the rear wheel to spin freely to perform common
maintenance procedures such as chain cleaning, lubing or adjusting, and tire
or
wheel inspection and cleaning. Accordingly, it is desirable to provide a
lifting
mechanism for raising the rear of the motorcycle off the ground so the rear
wheel
may spin freely. Various mechanisms for raising a motorcycle's rear wheel are
known. However such mechanisms are typically over sized, mechanically complex,
unstable, difficult to use, not portable, not compactly stored, and not easily
adjusted.
The invention ameliorates the problems discussed above by providing a
motorcycle
jack, which is simple to use, easily adjustable, collapsible to a compact
storage
configuration, portable, lightweight, stable, and mechanically simple.
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PRIOR ART:
US 7,188,854 B1
US 2010/0001239 A1
US 6073915
US 2010/0320429 A1
CA 2406487 A1
US 5,118,126
SUMMARY OF THE INVENTION
According to the invention there is provided a portable adjustable jack
for raising the rear wheel of a motorcycle parked on its side stand being
comprised
of:
a channel shaped base member having a web and two side flanges;
a channel shaped lifting arm having a web and two side flanges;
a connecting pin mounting the lifting arm within the base member for
pivotal movement between a folded position in which the lifting arm is
contained
within the base member and an extended position in which the lifting arm moves
over-center to extend outwardly from the base member at an over-center angle
to
the base member to an upper end for supporting the rear wheel;
said side flanges of the lifting arm being connected to said side flanges
of the base member;
the web of the lifting arm being shaped at the upper end to a "V" cut
out or other concave shape to contact with a lifting point on the motorcycle;
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wherein the said lifting arm has the side flanges thereof at the end that
contacts the motorcycle formed at an angle inclined away from the web thereof
to
provide for usage on motorcycles with limited clearance caused by exhaust
pipes,
fenders, or other attachments at the rear of the motorcycle.
Preferably the base has a plurality of apertures in the flanges at
varying distances from each end of the base allowing the assembled device to
be
adjustable.
According to a second aspect of the invention there is provided a
portable adjustable jack for raising the rear wheel of a motorcycle parked on
its side
stand being comprised of:
a channel shaped base member having a web and two side flanges;
a channel shaped lifting arm having a web and two side flanges;
a connecting pin mounting the lifting arm within the base member for
pivotal movement between a folded position in which the lifting arm is
contained
within the base member and an extended position in which the lifting arm moves
over-center to extend outwardly from the base member at an over-center angle
to
the base member to an upper end for supporting the rear wheel;
said side flanges of the lifting arm being connected to said side flanges
of the base member;
the web of the lifting arm being shaped at the upper end to a "V" cut
out or other concave shape to contact with a lifting point on the motorcycle;
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wherein the base member has a plurality of apertures in the side
flanges thereof at varying distances from each end of the base member for
receiving
the connecting pin allowing the assembled device to be adjustable;
and wherein the lifting arm has an angled cut out in the side flanges
thereof which extends from the connecting pin partially down the length of the
lifting
arm allowing the lifting arm to maintain said over-center angle to provide the
over-
centre locking operation in the extended position despite which one of said
apertures
in the side flanges of the base member is selected.
Preferably the base has the apertures in the flange positioned slightly
nearer the open side of the channel shaped channel allowing the lifting arm to
rotate
freely within the base.
Preferably the said lifting arm has an outside web width smaller than
the inside dimensions of the base allowing it to fit within the base.
Preferably the said lifting arm has an appropriate length to allow it to
fold completely within the base when assembled to its shortest length for
compact
storage when not in use.
Preferably the said lifting arm has the flanges rounded or trimmed
around the aperture and includes a cut out in the web so the lifting arm can
rotate
within the base without obstruction.
Preferably the said lifting arm has the flanges at the end that contacts
the motorcycle formed at an angle inclined away from the web to provide for
usage
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on motorcycles with limited clearance caused by exhaust pipes, fenders, or
other
attachments at the rear of the motorcycle.
Preferably has an angled cut out in the flange which extends from the
rounded hinging end partially or completely down the length of the lifting arm
5 allowing the invention to maintain the angle required to provide the over-
centre
locking operation when engaged despite which apertures in the flanges are
selected.
Because of the geometry of the device, it is capable of lifting a heavy
motorcycle using lightweight materials.
Because of the hinging action, heavy motorcycles can be lifted easily.
The "V" tip centres and keeps the jack on its lifting point.
The apertures at varying distances from the ends of the base allow
adjustability.
The cut out in the lifting arm maintains the over centre locking position
despite which apertures are selected.
The spacers maintain the tension because the moving parts of the
device (the base and the lifting arm) never contact each other directly.
The rounded end of the lifting arm, the cut out in the web of the lifting
arm, and the off-centre apertures in the flanges allow the lifting arm to
rotate freely
within the base.
The invention folds to a compact configuration for storage and
transport.
BRIEF DESCRIPTION OF THE DRAWINGS:
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FIG 1. is an oblique view of the base portion of the invention.
FIG 2. is an oblique view of the lifting arm portion of the invention.
FIG 3. is a top view of the lifting arm portion of the invention.
FIG 4. is an oblique view of the assembled invention in the closed
position.
FIG 5. is a top view of the assembled invention in the closed position.
FIG 6. is a bottom oblique view of the assembled invention in the
engaged position.
FIG 7. is a top oblique view of the assembled invention in the engaged
position.
FIG 8. is a rear view of a motorcycle canted to its left resting on its
sidestand with the invention in the pre-engaged position.
FIG 9. is a rear view of a motorcycle canted to its left resting on its
sidestand with the invention in the engaged position and the rear wheel
clearing the
ground.
FIG 10. is a side view of the rear main components of a motorcycle
with the invention in position.
DETAILED DESCRIPTION:
FIG-1 is an oblique view of the base (1) portion of the invention
showing one or multiple apertures (3) available on each flange at varying
distances
from each end of the base (1).
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FIG-2 is an oblique view of the lifting arm (2) portion of the invention
showing:
Aperture (4) for connection to base (1)
Angled cut out (5) on the flange which extends from the rounded
hinging end of the lifting arm (2) partially or completely down the length of
the lifting
arm (2).
Angled cut (6).
"V" cut out (7) or other concave shape.
FIG-3 is a top view of the lifting arm (2) portion of the invention
showing:
"V" cut out (7) or other concave shape.
Cut out (8) allowing the lifting arm (2) to rotate within the base (1).
FIG-4 is an oblique view of the assembled invention folded in on itself
for storage. The base (1) is connected to the lifting arm (2) utilizing pin
(9) and
tensioning device (10).
FIG-5 is a top view of the assembled invention folded in on itself for
storage. The base (1) is connected to the lifting arm (2) utilizing pin (9),
the
tensioning device (10), and spacers (11) to keep the base (1) from directly
contacting the lifting arm (2).
FIG-6 and FIG-7 are front and rear oblique views of the assembled
invention in its engaged position. The angled cut out (5) in the lifting arm
(2) allows
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the invention to maintain a consistent over-centre lock irrespective of which
sizing
aperture (3) on the base (1) is selected.
FIG-8 is a rear view of a motorcycle canted to its left resting on its
sidestand (15) with the invention in its pre-engaged position. The lifting arm
(2) is in
contact with the rear of the motorcycle at a lifting point (14). Most lifting
points (14)
on the motorcycle will be attachments to the swingarm (13). The rear tire (12)
of the
motorcycle rests on the ground (16) and therefore locked in position by the
weight of
the motorcycle and unable to spin freely.
FIG-9 is a rear view of a motorcycle canted to its left resting on its
sidestand (15) with the invention in its engaged position. The lifting arm (2)
is in
contact with the motorcycle at a lifting point (14) on the swingarm (13). The
rear tire
(12) of the motorcycle is raised off the ground (16) and therefore able to
spin freely.
FIG-10 is a side view of the rear main components of a motorcycle
including the tire (12), the swingarm (13), the lifting point (14), the ground
(16), and
the assembled invention (1) and (2). The invention is in the pre-engaged
position as
the tire (12) is still in contact with the ground (16). The lifting arm (2) is
in contact
with the motorcycle at a lifting point (14) showing the "V" cut out (7) or
concave
notch that holds the device on the centre of the lifting point (14).
The invention is comprised of a base piece (1), a lifting arm (2), a pin
(9) connecting the base (1) and the lifting arm (2), secured with a tensioning
device
(10).
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When assembled, the base (1) and the lifting arm (2) are separated by
spacers (11) so as not to come into direct contact with each other.
The base (1) in its preferred embodiment is formed from "C" shaped
aluminium channel. The preferred dimensions are 9 inches in length, with a
base of
2 inches, and flanges of 1 inch. One or multiple apertures are available on
the
flanges to accept the joining pin (9) to connect the base (1) with the lifting
arm (2).
In the case of multiple apertures (3), the apertures (3) are available on each
flange
at varying distances from each end of the base (1). This configuration allows
for
extensive adjustability without jeopardizing the strength of the device. The
apertures
(3) are not necessarily centred on the base's (1) flange, but may be
positioned
slightly towards the open side of the "C" channel to allow the lifting arm (2)
to move
freely and reach an over-centre locked position when the invention is engaged.
The base (1) may be constructed of other materials, in differing
dimensions, and with a single aperture (3) or a multitude of apertures (3) but
the
materials, dimensions, and construction described have shown to be light and
strong, and also provide sufficient adjustability and an appropriately stable
foundation for the motorcycle when the invention is engaged.
The lifting arm (2) in its preferred embodiment is formed from "C"
shaped aluminium channel with its outside base width being slightly smaller
than the
inside dimensions of the base (1) allowing it to fit within the base (1). The
preferred
length of the lifting arm (2) is 7 inches allowing it to fold completely
within the base
(1) for compact storage when not in use.
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When the lifting arm (2) is placed within the flanges of the base (1), the
apertures (3) on the base (1) and the apertures (4) on the lifting arm (2)
accept the
pin (9), the two spacers (11), and the tensioning device (10) to form the
complete
assembled invention. The lifting arm (2) has the flanges rounded around the
5 aperture (4) and includes a cut out (8) allowing the lifting arm (2) to
rotate within the
base (1) without obstruction. The opposite end of the lifting arm (2) can be
formed
at an angle (6) to provide for usage on motorcycles with limited clearance
caused by
exhaust pipes, fenders, or other attachments at the rear of the motorcycle.
The end
of the lifting arm (2) that engages the motorcycle includes a "V" cut out (7)
or other
10 concave shape to ensure proper and secure contact with the lifting point
(14) on the
motorcycle. The flange on the lifting arm (2) includes an angled cut out (5),
which
extends from the rounded hinged end of the lifting arm (2) partially or
completely
down the length of the lifting arm (2). This allows the invention to maintain
the angle
required to provide the over-centre locking operation when engaged as shown in
FIG-6, FIG-7, and FIG-9 despite which apertures (3) in the base (1) are
selected.
The lifting arm (2) may be constructed of other materials, in differing
dimensions and shapes, but the materials, dimensions, and construction
described
have shown to be light and strong, and also provide sufficient adjustability
and an
appropriately stable foundation for the motorcycle when the invention is
engaged.
The preferred embodiment of the pin (9) is a common steel machine
bolt with enough threading on the shaft to accept the tensioning device (10),
which
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may be a common nut. The pin (9) and tensioning device (10) may be comprised
of
components constructed from different materials in other configurations.
The spacers (11) are assembled on the pin (9) between the base (1)
and the lifting arm (2). The spacers (11) can be comprised of metal, nylon, or
any
other appropriate materials. The spacers (11) responsibility is to separate
the base
(1) from the lifting arm (2) so that the invention can be operated repeatedly
without
affecting the tension between the moving parts of the invention. When the
device is
assembled, the tensioning device (10) is slightly tightened to provide nominal
friction
between the spacers (11) and the base (1) and the lifting arm (2). This
nominal
friction allows the invention to be opened easily to any angle and allow it to
maintain
that position with no further mechanical or human intervention required. This
allows
the invention to be set in its pre-engaged position as shown in FIG-8 and then
engaged as shown in FIG-9 while keeping the users hands safely clear of
operation.
For operation, the invention is placed in the pre-engaged position
shown in FIG-8 and FIG-10 and then engaged as shown in FIG-9 by the user by
applying pressure on the base (1) at the pivot point of the base (1) and
lifting arm (2)
with their foot downwardly and towards the motorcycle. The invention extends
and
lifts the rear of the motorcycle and then rotates past 180 degrees into the
over-
centre locking position. When the invention is engaged, the rear tire (12) of
the
motorcycle rises slightly off the ground (16) allowing it (12) to spin freely.
To disengage the invention from the lifted motorcycle, the user pushes
on the inside pivot point formed by the base (1) and the lifting an-n (2) of
the
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invention outwardly and away from the motorcycle enough to overcome the over-
centre locked position. The invention then disengages and the motorcycle's
rear tire
(12) settles onto the ground (16).
The safe operation of the invention is most importantly dependent on
the strength of the motorcycle's sidestand (15). Generally motorcycles are
supplied
with sidestands (15) that are over-engineered to withstand substantially
greater
stress loads than that which would occur by simply canting the motorcycle to
its side
and resting it on the sidestand (15). However with continuing efforts to
reduce the
weight of motorcycles, some may be supplied with a sidestand (15) that is not
capable of carrying the additional weight the invention would transfer to the
sidestand (15) while engaged.
The invention is intended to lift the rear tire (12) off the ground (16)
only enough to allow the rear tire (12) to spin freely. If for any reason the
invention
should fail, the motorcycle only drops a minimal distance to the ground (16)
and the
impact is easily absorbed by the motorcycle's suspension.
The effectiveness of the invention may be hindered by the placement
of the sidestand (15) on the motorcycle. Cruiser style motorcycles typically
have the
sidestand (15) positioned further forward on the motorcycle's frame and the
weight
distribution between the invention, and the front and rear wheels are not
shared
proportionately. This can cause the motorcycle rear tire (12) to slide across
the
ground (16) instead of lifting the rear tire (12) off the ground (16).
