Note: Descriptions are shown in the official language in which they were submitted.
2121111
-- This invention relates to lateral extension devices for a plafform
of a vehicle lift of the type which supports a vehicle atop a pair of elevatableplafforms by means of the vehicle undercarriage, there generally being
support blocks interposed between the carriage and plafforms. In particular,
5 the present invention provides an arm positionable to provide support for the
undercarriage laterally beyond the support area of the plafform. The
invention also provides a method of equipping such a plafform with the lateral
extension device.
Vehicle lifts having paired rectangular plafforms are used in
10 servicing vehicles. Devices which support vehicles by means of a vehicle
frame or undercarriage are generally used where servicing of the vehicle tires
is necessary, such as for tire rotation. Of course, other maintenance or
service activities can be performed by use of such a device which provides
access to the underside of a vehicle.
Generally speaking, in use, a vehicle is not supported directly
on the plafforms of such a lift. Rather, rubber blocks are placed on the
plafforms directly below the portion of the vehicle frame to be supported.
Usually, four blocks are used, one below each corner area of the vehicle. Of
necessity then, the dimensions and spacing of the lift plafforms must take
20 into account the requirement that access be had to the vehicle wheels when
the lift is in its elevated position. Generally speaking, the aproach has been
to provide platforms of length shorter than the inner distance between front
and rear wheels of the vehicle.
This constraint has led to a problem with respect to
25 accommodation of vehicles of various sizes. Particularly, there are vehicles,such as small trucks, having relatively large frames for which it is difficult or
even impossible to locate rubber blocks for proper frame support on
conventionally configured lift plafforms.
- 2121111
-- 2 --
One approach to this problem has been the use of extension
members for longitudinal extension of commercially available lift plafforms.
Currently available extension members are of the same width as the lift
plafforms. Such a member includes a rectangular plafform extension area
5 having a pair of angle members running along two sides and extending
beyond the extension area. There are open grips at the free ends of the
angle members for engaging the lengthwise edges of a lift plafform. The
arrangement is such that the plafform edges are received within the grips
and the extension is located with the extension area adjacent the plafform
10 support area with upper horizontal arms of the angle members shouldered
along edges of the lift plafform.
This approach has the advantage of extending the length of
available support plafform area and installation of the extension members
involves no great skill. There are, unfortunately, a number of disadvantages.
15 One is, of course, that the extension members must be stored when not in
use.
A second disadvantage is related to the fact that many lifts are
installed such that when in the lowered position, the plafforms are sunken
into the surrounding area with the plafform upper support area flush, or at
20 least nearly flush with the surrounding area. The surrounding area, say a
garage floor, generally comes up to the outer edges of the plafforms to
present a relatively continuous floor area. It is therefore necessary to
partially elevate the plafforms before installation of the extensions, which is
inconvenient.
It can also be seen that any such extension necessarily
diminishes accessibility to the underside of the vehicle to service personnel.
2121111
In a broad aspect, the present invention provides a device for
lifting a vehicle having an undercarriage. The device includes a pair of
spaced apart plafforms, each plafform having a generally horizontal support
surface, each surface being coplanar with the other, for location thereon of
5 blocks for supporting the undercarriage of the vehicle. A jack is operably
connected to the plafforms for up and down movement of the platforms. A
lateral extension means for at least one of the surfaces is provided. The
extension means includes an arm pivotally connected atop one of the
plafforms such that the arm may be rotatably positioned with a portion of a
10 top surface thereof located laterally beyond the plafform surface for location
of a block on the portion of the top surface for supporting the vehicle
undercarrlage.
The device thus provides an adapter for a plafform of vehicle lift
to extend the support area of the platform. It may be included as part of the
15 lift or may be incoporated as part of an existing lift.
The arm can include an aperture in one of its ends be pivotally
connected to the plafform by a headed member inserted through the aperture
and secured to the plafform. In the preferred embodiment, the arm is a slot
located such that the arm is longitudinally slidable as well as rotatable with
20 respect to the headed member.
The extension means can be secured to a platform, as
described below in connection with the preferred embodiment, by an
apertured plate mounted below the underside of the plafform. The apertures
of the plate communicate with corresponding apertures in the plafform and
25 the headed member. Fasteners, such as threaded bolts, are inserted
through the corresponding apertures in the plate, plafform and headed
member to secure the headed member, and thus the extension means to the
plafform.
2121111
_ -- 4 --
Most often, the jack is a scissor jack which includes, for each
plafform, a first support member pivotally connected to the underside of the
plafform along a horizontal axis but at the same time being fixed against
horizontal movement with respect to the plafform. There is a second support
5 member pivotally connected to the first member, the upper end of the second
support member being horizontally movable with respect to the plafform
along its lengthwise axis, most such plafforms being rectangular. Generally,
there is a pair of such first support members rigidly connected to each other
and a pair of such second support members rigidly connected to each other.
10 The upper ends of the second support members are connected to each other
by a shaft fitted with rollers, which rollers are in horizontal rolling contact with
an underside of the plafform.
Each apertured plate extends downwardly from the underside of
the plafform and the rollers are dimensioned to provide a clearance between
15 the shaft and the underside of the plafform for the plate. This permits the
upper ends of the second support members, during their horizontal travel, to
pass by under the apertured plate during the lifting and lowering operations
of the jack.
The arm of a lifting device of the present invention can include
20 mounting means for a block housing situated in the arm surface locatable
laterally beyond the platform surface. The mounting means preferably is a
hole in the arm and the block housing includes a downwardly directed pin for
receipt in the hole. Optionally, the device includes the block housing and/or
the block.
Another option is the provision of a low friction material along
the portion of the underside of the arm in abutment with the plafform surface
for reducing friction between the arm and surface during movement of the
arm.
2121111
-- 5 --
The support surface of each plafform is often rectangular and
usuallly, the device includes a pair of the lateral extension means on each
plafform, each located at a longitudinal end of the plafform.
Preferably, each arm may be positioned in a retracted position
5 within edges of the rectangular plafform to which it is connected and there is a cover for each of the arms, positionable over the arms when in the
retracted position. Each cover can include a pair of cavities, one each for
receipt of an upper portion of the headed member, for holding the cover in
place. It would be usual for the underside of the cover to be largely
10 supported by the arms in the retracted positions, to permit blocks to be
placed on the cover for supporting the vehicle undercarriage, if this happened
to be necessary.
In a second broad aspect, the present invention is a method of
equipping a plafform of a device for lifting a vehicle having an undercarriage
15 with lateral extension means. This method could be used, for example, to
retrofit existing lifts or it could be included in manufacturing of a new lift.
According to the method, there is a pair of spaced apart
plafforms for supporting the vehicle by means of the undercarriage, each
plafform having a generally horizontal support surface and each surface
20 being coplanar with the other, and a jack operably connected to the plafforms for up and down movement of the plafforms. The method includes mounting
an arm pivotally atop one of the plafforms at a point central of the surface of
the plafform such that the arm may be rotatably positioned with a top surface
thereof locatable laterally beyond the platform surface for support of the
25 vehicle.
- 2121111
_ -- 6
It is possible for the arm to have an aperture in one of its ends
so that the method includes the step of connecting the arm to the platform by
a headed member inserted through the aperture.
The the aperture can be a slot located such that the arm is
5 longitudinally slidable with respect to the headed member and the headed
member can include a plurality of downwardly open apertures. The method
would thus include forming, for example by drilling, apertures corresponding
to the apertures of the headed member in the plafform and locating below
the underside of the plafform an apertured plate with corresponding apertures
10 of the plate, plafform and headed member in communication with each other
and securing fasteners through the communicating apertures.
Particularly, the invention also includes a method of equipping a
plafform of a device for lifting a vehicle having an undercarriage with lateral
extension means, in which the device includes a pair of spaced apart
15 platforms for locating blocks thereon for supporting the vehicle by means of
the undercarriage, each plafform having a generally horizontal support
surface and each surface being coplanar with the other, and a scissor jack
operably connected to the plafforms for up and down movement of the
plafforms, the jack including, for each plafform, a first support member
20 pivotally connected to the underside of the plafform along a horizontal axis
and being fixed against horizontal movement with respect to the plafform and
a second support member pivotally connected to the first member, the
second support member being horizontally movable with respect to the
plafform, wherein there is a pair of such first support members rigidly
25 connected to each other and a pair of such second support members rigidly
connected to each other, wherein the upper ends of the second support
members are connected to each other by a shaft fitted with rollers in
horizontal rolling contact with the underside of the platform, and wherein the
rollers are dimensioned to provide a clearance between the shaft and the
2121111
.~ -- 7 -
underside of the plafform for the plate, in which the method includes
providing an aperture through the support surface of such a plafform, and
mounting an arm pivotally atop one of the plafforms by means which passes
through the aperture and extends into the clearance and abuts the underside
of the plafform to permit rotationally positioning the arm with a top surface
thereof located laterally beyond the plafform support surface for location of a
block on the top surface for support of the vehicle.
In the drawings, which illustrate an embodiment of the invention,
Figure 1 illustrates a typical scissor lift with a known plafform
extension installed,
Figure 2 is an isometric view showing the top, side and an end
of the upper portions of a lift having a plafform extension of the present
nvention,
Figure 3 is a vertical section of the plafform and extension of
the present invention taken along a line 3-3 of Figure 2, and
Figure 4 is an exploded sectional view of the Figure 2
embodiment of the present invention taken along line 4-4 of Figure 2.
Turning to the drawings, scissor lift 10 having scissor jack 11 is
shown in an elevated position supporting a vehicle in Figure 1 on spaced
apart plafforms 12. Each plafform 12 has known rear extension member 14
connected thereto. The vehicle undercarriage sits on rubber blocks 16 each
of which in turn sits directly on one of the plafforms. During the lifting and
lowering operations, each of the upper ends of jack members 18 moves
horizontally along the underside of the plafform it supports. Each of the
upper ends of jack member 20 is pivotally connected to the underside of the
2121111
~_ - 8
plafform along a horizontal axis transverse to the lengthwise direction of the
plafform, but at the same time jack member 20 is horizontally fixed with
respect to the plafform, in a fashion understood by those skilled in the art.
Movement of the lift is driven by pistons 22. As can be seen, each platform
5 is supported by pairs of such members, there being a pair of jack members
18 rigidly connected to each other and a pair of jack members 20 being
rigidly connected to each other by cross-stuts. Members 18, 20 are pivotally
connected to each other. The term "scissor jack" or "scissor lift" derives from
the resemblance between this arrangement and a pair of scissors.
The upper ends of paired jack members 18 are connected to
each other by shaft 24 shown in Figure 3. Each shaft end is fitted with roller
26 each of which is in direct rolling contact with the underside of the plafformsupported by the member. Roller 26 is shown in phantom in Figure 3 and
the horizontal back and forth direction of movement of shaft 24 is indicated
15 by arrow 28, this direction corresponding to the horizontal direction of
movement of the upper ends of jack members 18.
Each plafform provides a generally rectangular and horizontal
upper support surface 30. The plafforms are coplanar with each other, that
is, the support surface of one is the same height as the other and their
20 positions with respect to each other remain unchanged as the jack moves the
supports up and down. In this way, relatively flat coplanar surfaces are
provided for the placement of blocks 16 which in turn support the
undercarriage of a vehicle to be raised to an elevated position by the lift.
Each platform is provided with arms 32 for lateral extension of
25 the surface available for support of a vehicle by the lift. Each plafform has a
pair of arms 32, one arm at each longitudinal end of the platform. The arms
of the preferred embodiment are essentially identical to each other, and as
2121111
such comments made with respect to one arm would generally apply to the
remaining arms.
Arm 32 is connected atop plafform 12 by headed member 34.
Headed member 34 is fastened to the plafform by means of apertured plate
5 36 in abutting contact with the underside of the plafform and threaded bolts
38. The bolts are each inserted through communicating plate apertures 39,
plafform apertures 40 and headed member apertures 42. Apertures of the
headed member are downwardly open threaded holes into which the matingly
threaded bolts are threadedly engaged.
The elongate arm has slot 44 through which the stubby shank
45 of the headed member is inserted. Slot 44 is sized so the arm is held
atop the plafform. Arm portions surrounding the slot are sandwiched
between head 64 and the support surface 30 so that the arm is freely
rotatable about vertical pivot axis 49. The arm can thus be rotated
15 horizontally with respect to the headed member as indicated by direction
arrow 46. The arm is also horizontally slidable back and forth along the
longitudinal axis of the slot with respect to the headed member as indicated
by direction arrow 48 which emanates from axis 49. Of course, the position
of arrow 48 is determined by the rotational position of the arm which can
swing a full 360 about axis 49. The underside of the arm can be coated or
have adhesively or otherwise affixed thereto a low-friction material such as
neoprene. Such material would enhance movement of the arm with respect
to the plafform, and assist in preserving the surface of the plafform against
which the arm slides and rotates.
The arm is dimensioned such that its free end 50 may be
positioned laterally beyond plafform surface 30 to thereby effectively extend
the surface area available for locating a block for support of a vehicle.
2121111
- 10-
ln the disclosed embodiment, the arm is provided in its free end
with hole 51 for the mounting of block housing 52. Block housing 52 has
downwardly depending pin 54 which is rotatably received with hole 51. Block
housing 54 has upwardly facing surface 56 upon which sits rubber spacer
block 58 for supporting a vehicle undercarriage. The block housing surface
area is surrounded by upstanding walls 60 for holding the block in the
housing.
The load-bearing portion of an arm which extends beyond the
edge of the plafform to which the arm is connected is supported by the
underlying plafform while the slotted end is held down by the headed
member. It will be appreciated that the strength and dimensions of the arm,
plafform, headed member and securing bolts combine to determine the load
capacity of the load-bearing portion of the arm of the disclosed embodiment.
The lifting device of the present invention thus includes means
for laterally extending the surface available for locating a block for supporting
the undercarriage of a vehicle laterally beyond the rectangular upper areas
provided by the plafforms. As can be appreciated from the drawings, the
available area can be extended longitudinally beyond the ends of the
rectangular platforms and the support area can be extended beyond the
lengthwise sides or edges of the rectangular area, as desired.
When not in use, or when the extended support area is not
needed, each of the arms can be positioned in a retracted position as shown
in the plafform to the right in Figure 2. Cover 62 is fitted over each pair of
retracted arms (block housings having been removed) of a plafform. Heads
64 of headed members 34 project into cavities or apertures 66 of the cover
to hold the cover in place. As can be seen from Figure 4, the underside of
the cover is largely supported by the arms in their retracted positions. The
ends and center portions of the cover are supported by hollow transverse
2121111
-11 -
members 68. In this way, rubber spacer blocks may be placed on the cover,
if this is so desired when the extension arms are not in use.
An existing lift may be equipped with the arm and mounting
means described above to increase the utility of the lift. Such a retlofilling
process would involve drilling, or otherwise providing plafforms with holes 40
in a suitable location. In the disclosed embodiment, the holes are provided
in the central area of each of the plafform rectangles and particularly so as tolocate the headed member on the longitudinal center line of the rectangle,
but any central position which provides appropriate strength for support of a
vehicle would be suitable. Once holes for insertion of shanks of bolts 38
therethrough are provided, an arm is suitably located on the plafform, that is,
the arm is moved into place so that its slot is located to overlie the holes to
permit installation of a headed member 34. The stubby shank of the
threaded member is thus inserted downwardly into the slot so that its
threaded aperture 42 communicate with apertures 40 of the plafform. The
apertured plate is moved into place with its apertures in communication with
the plafform and headed member holes and bolts 38 threadingly installed.
Flat headed bolts would generally have slots in their heads for such purpose.
Typical support area dimensions of plafforms are about 36
inches long by 22 inches wide (about 91 cm by about 56 cm). The overall
length of the extension arm of the preferred embodiment is about twenty-two
inches and generally the pivot point (location of the center of the headed
member) is spaced eight inches from the longitudinal end of a plafform while
being located along a longitudinal center line. The width of the wide portion
of the arm is about six inches and the arm has a thickness of about one inch.
The slot of the arm is about twelve inches long and about two inches wide
and the slot extends to within about one inch of the end of the arm. The
hole for the block housing has a radius of about % inches (1.9 cm) and is
centered at a point about 11/4 inches (3.2 cm) from the end of the arm. The
2121111
- - 12-
apertured bottom plate has a radius of about 43/4 inches (12 cm) and a
thickness of about 3/8 inches (95 cm). Clearance between shaft 24 and the
underside of bottom plate 36, as it extends downwardly below the underside
surface of the plafform, is about 1/8 inches (0.32 cm). The extent of the
5 clearance in such an arrangement is determined by the outer radius of rollers
26. The arm, headed member and apertured plate are all made of material,
such as steel, of suitable strength. The cover is about 81/4 inches (21 cm)
wide and 54 inches (137 cm) long with its hollow end support members
adding about another two inches to its overall length. The cover of the
10 disclosed embodiment is of 11 gauge H.R.S. plate. Rubber blocks are
typically about five inches cubed.
It is possible with the present invention to obtain lateral
extension members suitable for use in supporting vehicles of at least 7000
pounds. For example, a commercially available scissor lift known as
15 SPACEMAX 7000 and currently available from Hydralift Industries Ltd. of
Richmond Hill, Ontario, Canada can be readily ret,orilled with the extension
described herein by the process described above.
