WO1987006569A1

WO1987006569A1 - Garage vehicle hoist

Info

Publication number: WO1987006569A1
Application number: PCT/US1987/000973
Authority: WO
Inventors: Stephen J. F. Kertesz
Original assignee: Brodmann, George, L.
Priority date: 1986-04-30
Filing date: 1987-04-30
Publication date: 1987-11-05
Also published as: EP0265510A1; GB8610634D0

Abstract

A vehicle lift which has the capability of being operated in a number of different lift modes, including selecting between a conventional horizontal lift mode, or a tilt mode, or a lift mode which combines aspects of both the horizontal and tilt modes. The manner in which this is accomplished involves relocating one of the hinge points (13) of the lift linkage (44) on each side of the frame (22), which results in modifying the linkage geometry to convert the lift from one mode to another.

Description

GARAGE VEHICLE HOIST FIELD OF THE INVENTION The present invention relates to various improve vehicle hoists used in garages and service stations that ma be either mobile or fixed. BACKGROUND OF THE INVENTION

Access to the underside of automotive vehicles i frequently necessary in order to carry out certai maintenance and repairs. There are numerous different type and designs of vehicle lifts, both of the platform type an of the "wheel-free" type, with each best suited t particular jobs. It has been recognized for some time tha for many jobs, tilting the vehicle, as well as lifting it is most useful, since the undersurface of the vehicle to b serviced, being thus tilted, makes it more comfortable fo the mechanic to work on. Also, it helps natural light t better reach and illuminate the areas worked on. Because o these factors on such jobs, productivity will rise while, a the same time, operator fatigue will diminish. However, i is also recognized that fpr many other jobs, the mor conventional horizontal lift will still result in the mos comfortable position conducive to highest productivity an lowest rate of fatigue. Some lifts are known that can lif and tilt vehicles simultaneously, such as U.S. Patent No 3,844,421 (or tilt once the lifting has ceased), but thes all share one or more of the following drawbacks: a) bad access to much of the underside of th vehicle; b) insufficient maximum height of the lift; and c) complicated and therefore less- reliable, mor difficult to use, and rather expensive.

It is therefore desirable that lifts be made available that overcome one or more of" the aforementioned drawbacks.

OBJECTS OF THE INVENTION

It is a primary object of the invention to provide an improved vehicle lift, either of the fixed or mobile type.

The lift of the present invention allows the mechanic to select, prior to the commencement of lifting, whether a horizontal lift mode or a mode-combining lift with tilt is desired (and in some cases also select the direction and extent of tilt desired). Furthermore, the design must be simple to construct and to use, reliable, and less expensive than prior art designs.

SUMMARY OF THE INVENTION

In accordance with the present invention, there is provided a vehicle lift which has the capability of being operated in a number of different lift modes, including selecting between a conventional horizontal lift mode, or a tilt mode, or a lift mode which combines aspects of both the horizontal and tilt modes.

The manner in which this is accomplished involves relocating one of the hinge points of the lift linkage on each side of the frame, which results in modifying the linkage geometry to convert the lift from one mode to another.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 illustrates a side view of a lift showing parallelogram-type linkage;

Figure 2 is a plan view of the lift in Figure 1; Figure 3 is a diagrammatic illustration showing th lift of Figure 1 modified in accordance with the present invention and showing the- lift platform at various tilt positions;

Figure 4 is a diagrammatic illustration showing the lift of Figure 1 modified in a different manner and showing the lift platform at various horizontal and tilt positions;

Figure 5 illustrates a side view of a different type of lift;

Figure 6 is a diagrammatic illustration showing the lift of Figure 5 modified in accordance with the presen invention and showing the lift platform at various til positions;

Figure 7 is a diagrammatic illustration showing th lift of Figure 5 modified in a different manner and showin the lift platform at various horizontal and tilt positions;

Figure 8 is an end view of a pair of pins used in th lift of the present invention; and

Figure 9 is an elevational view of the pins shown in Figure 8. DESCRIPTION OF THE PREFERRED EMBODIMENTS

In Figures 1 and 2, there is shown a movable vehicl lift 20 of the "wheel-free" type. This means that when vehicle is lifted on such a lift, its wheels are free in mi air. The lift 20 includes a U-shaped base frame 22 wit wheels 24 mounted on one end as shown, which, in combinatio with one or more wheels not shown), support the other en of said frame and allow the lift to be rolled around in conventional manner.

The vehicle is supported and lifted by two pairs o supporting arms 26, 28 and 30, 32 which form a vehicl support platform. Alternatively, one or more soli platforms may be used instead of individual supportin arms. Each one of these supporting arms is hinged at on end at hinge points 34, 36, 38, and 40 and is telescopic o adjustable in length, with lift pads 42 being disposed a the end of each arm.

On each side of the frame is a parallelogram type o linkage 44 having hinge points 11, 12, 13, and 14, as show in Figures 1 and 2. The linkage 44 includes a main lift ar 46, a guide arm 48, and a "short" link 50. The fourth lin of the parallelogram linkage 44 is an integral part of fram 22 and extends between hinge points 13 and 14. When link 5 pivots about hinge point 11, the supporting arms 26 and 2 also pivot with it about the same hinge point 11. This together with the known way that parallelogram linkage perform, insures that the supporting arms remain horizonta during the entire lifting and lowering operation, irrespective of the height to which pivot points 11 are raised.

The main lift arms 46 may be controllably raised and lowered by any one of several known conventional ways. For example, there is shown a pair of hydraulic cylinders 52 that are synchronized to extend and retract in unison. The necessary high pressure hydraulic fluid may be provided by known means, such as a pump 54 driven by either an electric motor 56 or a compressed air motor. The oil flow is controlled by a manual direction control valve 58 to effect either raising or lowering of the lift.

In the interest of safety and to comply with the national safety laws of many countries applying to vehicle lifts, it is necessary to provide some form of backup or safety system that does not allow the lift to collapse in the event of a loss of hydraulic pressure in one or both of said cylinders. One solution is to utilize hydraulic cylinders that are mechanically lockable in any position of extension. Such cylinders are described in my copending U.S. patent application. Serial No. 909,166, and PCT Application No. PCT/US 86/01954.

Lines X-X show the supporting arms 26, 28, 30, and 32 in their horizontal orientation and raised to their maximum height, while lines Y-Y represent the supporting arms again in their horizontal orientation but this time raised to some intermediate height. When the supporting arms are in their lowest horizontal position, hinge 11 moves in an arc to the position shown as Hi,. With the parallelogram- ype linkage described above, the supporting arms are maintained in a horizontal orientation, and tilting of the arms is not possible. However, in accordance with the teachings of the present invention, there is provided a system for modifying the parallelogram linkage into a non-parallelogram-type linkage which causes the supporting arms 26, 28, 30, and 32 to gradually move into tilted positions (as shown by dotted lines X'-X' and X"-X" in Figures 1 and 3 and Yχ-Yι in Figures 1 and 4) as the supporting arms are raised from their ground position in which they are horizontal. As will also be explained, the lift shown in Figure 3 causes the supporting arms to change their angle of tilt as the supporting arms move from their ground position to their maximum lift position. However, the lift shown in Figure 4 causes the supporting arms to reach their maximum tilt at approximately half the maximum height, after which the supporting arms gradually return to their horizontal position as they move to their maximum height. In accordance with the present invention, as shown in Figure 3, the non-parallelogram type of linkage is achieved by changing the hinge 13 to new positions, such as 13* or 13". This is accomplished by disconnecting arms 48 and 22 from hinge 13, adjusting the effective length of arm 22, and reconnecting arm 48 to another hinge point, such as 13' or 13". The alternative hinge points 13' or 13" are located at predetermined positions on frame 22, and these predetermined positions can be located along the arc 15, in a manner to be explained, which will change the amount of tilt achieved at the maximum height. It should also be understood that any one of the four hinge points can be relocated in the same manner, as will be explained herein.

The manner of obtaining predetermined hinge points 13' and 13" will now be explained. When the supporting arms 26, 28, 30, and 32 are in their ground position (which is horizontal), hinge point 12 moves into position 12^ as shown, with angle alpha remaining the same in both positions. Using the distance between hinge points 12 and 13 as a radius, an arc 15 is drawn through hinge point 13 using hinge point 12L as the center of curvature. In order to establish the new hinge point along arc 15, one must first decide the tilt angle beta required at maximum height and the direction of tilt required. Line 11-12 is then rotated about point 11 through the desired angle beta to establish a new position 12* or 12". New point 12' is then used as the center of curvature, with the radius of curvature being equal to arm 12-13 to draw another arc 16' which intersects arc 15 at the new hinge point 13' . New point 12" is used in the same manner to draw another arc 16" which intersects arc 15 at new hinge point 13". New hinge 13' establishes a new linkage 44', and new hinge 13" establishes another new linkage 44".

As shown in Figure 3, new hinge point 13' will cause supporting arms 26, 28, 30, and 32, represented by line L~^XL dⁿ their ground position), to move upwardly and gradually tilt in a counterclockwise direction and move through various intermediate positions, represented by X'-X' to the maximum height position X'-X'.

As shown in Figure 3, new hinge point 13" will cause supporting arms 26, 28, 30, and 32, represented by XL~XL ( ⁿ their ground positions), to move upwardly and gradually tilt in a clockwise direction and move through various intermediate positions represented by X"-X" to the maximum height position X"-X". As will be understood, "13* and 13" are merely representative of numerous new hinge points along arc 15, depending on the degree and direction of tilt desired at the maximum height position.

In accordance with the present invention, as shown in Figure 4, the non-parallelogram type of linkage is achieved by changing the hinge 13 to a new position, such as 13χ. This is accomplished by disconnecting arms 48 and 22 from hinge 13, adjusting the effective length of arms 22 and 48, and reconnecting them to the new hinge point 13_. The alternative hinge point 13χ is located at a predetermined position on frame 22, and this predetermined position is established in a manner to be explained and will achieve the desired amount of tilt at an intermediate lift position, such as shown by Yι~Yι in Figure 4.

The manner of obtaining predetermined hinge point 13 ι will now be explained. When the supporting arms 26, 28, 30, and 32 are in their ground position (which is horizontal), hinge point 12 moves into position 12L as shown. When the lift is in its uppermost position and the supporting arm are horizontal, as shown by Y_H-YH, hinge 12 is in positio 12_H.

One then selects the desired angle gamma of tilt a some intermediate lift positions, an example of which i shown by line Yχ-Yι, which places hinge point 12 at positio 12χ. These three points 12L, 12I, and 12_H establish an ar 17 having a particular radius of curvature and center o curvature 13j_ which is found by ordinary geometry methods. As shown in Figure 4, new -hinge point 13χ will caus supporting arms 26, 28, 30, and 32, represented by lin YL-YJ, (in their ground position), to move upwardly an gradually tilt and move through various intermediat positions until it reaches the desired tilt position, a shown by line Yι~Yι having the desired tilt angle gamma Further lifting of the supporting arms will cause them t gradually rotate out of their tilted position Yχ-Yι back t a horizontal position when it reaches maximum height, a shown by line Yg-Yg. It should also be understood that an one of the four hinge points can be relocated in the sam manner.

It should also be understood, that if some degree o tilt, rather than horizontal, is desired at the .. maximu height of the lift, this can also be achieved using the sam procedure explained above. That is, the desired angle o the supporting arms (represented by Yg-Y_jj) at the maximu height establishes a new hinge point 12_∑j prime, which tak with hinge points 12^ and 12]_, establish a new arc and n hinge point 13χ prime, in the same manner as described above In fact, if one specifies the desired degree of ti for any three lift heights, this will clearly establish arc whose center and radius of curvature may again be simp found by ordinary geometry methods. Note that t degenerate case of the above is when one specifies t desired degree of tilt for two particular lift height This is because two points may be re.garded as the degenera case of three points, with any two of these three poin coinciding. It is known from ordinary geometry that infinite number of circular arcs may be drawn through a two points, with the center of these circles all lying on line that perpendicularly bisects the line connecting sa two points.

In Figure 5, there is shown a second type of movab vehicle lift 70, again of the "wheel-free" type, such that described in U.S. Patent No. 4,548,387. This lif unlike the type shown in Figures 1 and 2, is pushed und the vehicle to be lifted from the side of the vehicl Hence, when it is in its lowest position, much of t support arms or platform, as well as the main lift arm a leveling linkage, must be sufficiently near the ground pass freely under the vehicle to be lifted. This is o reason why a relatively more complicated linkage is utilized The lift 70 includes a smaller U-shaped base frame 72, with wheels 24 allowing the lift to be rolled around and under the vehicle to be lifted in a conventional manner.

The vehicle is supported and lifted by lift pads 76 that are located on the extremities of a telescopically-adjustable lift platform and support arm arrangement 78. The main lift arm 80 raises and lowers this lift platform 78 and is itself controllably raised and lowered by any one of several known conventional ways such as, for example, by means of a hydraulic cylinder (not shown). If a hydraulic cylinder is utilized to raise and lower the lift arm 80, then, in the interest of safety and to comply with the national safety laws of many countries applying to vehicle lifts, as stated before, it is necessary to provide some form of backup or safety system that does not allow the lift to collapse in the event of a loss of hydraulic pressure in said hydraulic cylinder.

One solution is to utilize a mechanically-lockable hydraulic cylinder, such as the type described in my various copending applications referenced earlier.

On each side of the lift arm 80, there is a leveling linkage consisting of two guide arms 82 and 84 and a boomerang-shaped linkage 86. These three leveling linkage components are hingedly connected, as shown in Figure 5 at hinge points 1, 2, 3, 4, 5, 6, and 7. This linkage, together with the lift arm 80, will be collectively referred to and is labeled as 88 in Figure 5. The leveling linkage maintains the lift platform 78 level, whether it is at its lowest ground position or any other raised position. It should be noted that it is the "correct" position of boomerang link 86 that (via guide arm 82) ensures that the platform 78 is level at all times. This "correct" position is assured by guide arm 84, or more exactly, the linkage connecting the four hinge points 4, 5, 6, and 7.

Lines A-A show the lift platform 78 in its horizontal orientation and raised to their maximum height, while lines B-B represent the lift platform again in its horizontal orientation but this time raised to some intermediate height. When the lift platform 78 is in its lowest horizontal position, hinge 1 moves in an arc to the position shown as lj.. With the linkage described above, the lift platform is maintained in a horizontal orientation, and the tilting of the platform is not possible.

However, in accordance with the teachings of the present invention, there is provided a system for modifying the aforementioned four-point linkage 4, 5, 6, and 7 in such _a way that this modified linkage will cause the lift platform 78 to gradually move into tilted positions (as shown by dotted lines A'-A¹ and A"-A" in Figures 5 and 6 and ^B1""^B1 ^{and B}11""^B11 iⁿ Figures 5 and 7) as the lift platform is raised from its ground position in which it is horizontal. As will also be explained, the lift shown in Figure 6 causes the lift platform to change its angle of tilt as the lift platform moves from its ground position to its maximum lift position. However, the lift shown in

Figure 7 causes the lift platform to reach its maximum tilt at approximately half the maximum height, after which the lift platform gradually returns to a horizontal position as it moves to its maximum height.

In accordance with the present invention, as shown in

Figure 6, the new linkage is achieved by changing the hinge

6 to new positions, such as .6' or 6". This is accomplished by disconnecting guide arm 84 and effective arm 72 from hinge 6 and reconnecting them to another hinge point, such as 6' or 6" after the effective length of arm 72 is adjusted. The alternative hinge points 6' or 6" are located at predetermined positions on frame 72, and their predetermined positions can be located along an arc 100, in a manner to be explained, which will change the amount of tilt achieved at the maximum height. The manner of obtaining predetermined hinge points 6¹ and 6" will now be explained.

When the lift platform is in its ground position (which is horizontal), hinge point 5 moves into position 5] Using the distance between hinge points 5 and 6, an arc 100 is drawn through hinge point 6 using hinge point 5L as the center of curvature. In order to establish the new hinge point along arc 100, one must first decide the tilt angle beta prime required and the direction of tilt required at the maximum height position. Line 1-2 is then rotated about point 1 through the desired angle beta prime to establish a new position 2' or 2". Because of t four-point linkage 1, 2, 3, and 4, the new positions 2' 2" for 2 determine corresponding new positions 3' or 3" f 3. Furthermore, because hinge points 3, 4, and 5 are all 5 boomerang-shaped linkage 86, the aforesaid new positions or 3" for 3 will give corresponding new positions 5¹ or for 5. New point 5' is then used as the center curvature, with the radius of curvature being equal to a 5-6 to draw another arc 101* which intersects arc 100 at t 0 new hinge point 6'. New point 5" -is used in the same mann to draw another arc 101" which intersects arc 100 at n hinge point 6". New hinge 6' establishes a new linkage 88 and new hinge 6" establishes another new linkage 88".

As shown in Figure 6, new hinge point 6* will cau the lift platform 78, represented by line

(in the ground position), to move upwardly and gradually tilt in counterclockwise direction and move through vario intermediate positions represented by A'-A' to the maxim height position A*-A*. As shown in Figure 6, new hinge point 6" will cau the lift platform 78, represented by line L-AJ. (in the ground position), to move upwardly and gradually tilt in clockwise direction and move through various intermedia positions, represented by A"-A" to the maximum heig 5 position A"-A".

As will be understood, 6' and 6" are mere representative of numerous new hinge points along arc 10 depending on the degree and direction of tile desired at the maximum height position. It should be understood that any one of the four hinge points 4, 5, 6, and 7 can be relocated in the above manner. in accordance with the present invention, as shown in Figure 7, the new linkage is achieved by changing the hinge 6 to new positions, such as 6χ or 6]_]_. This is accomplished by disconnecting guide arm 84 and arm 72 from hinge 6 and adjusting the effective length of arm 84 and reconnecting it to one of said new hinge points 6 or 6χχ. The alternative hinge points 6χ or 6^ are located at predetermined positions on frame 72, and these predetermined positions are established in a manner to be explained and will achieve the desired amount of tilt at an intermediate lift position, such as shown by Bχ-Bχ or B -Bχχ in Figure 7.

The manner of obtaining the predetermined hinge points 6χ and 6χχ will now be explained. When the lift platform 78 is in its ground position (which is horizontal), hinge point 5 moves into position 5j. as shown. When the lift is in its uppermost position and the lift platform 78 is horizontal, as shown by Bg-Bg, hinge point 5 is. in position 5β«

One then selects the angle gamma prime of tilt and the direction of tilt, desired at some intermediate lift position, examples of which are shown by lines Bχ-Bχ and Bιι-Bιχ. To obtain these desired tilts, line 1-2 is rotated about 1 through the desired direction and angle of til gamma prime establishing a new position 2χ or 2χχ. Again, because of the four-point linkage, these new positions 2χ o 2χχ for 2 will determine corresponding new position 3χ o 3χχ for 3. Furthermore, because hinge points 3, 4, and are all on boomerang-shaped linkage 86, the aforesaid ne positions 3χ or 3χχ for 3 will give corresponding ne positions 5χ or 5χχ for 5. Now, the three points 5χ., 5χ, and 5g establish an arc 102χ having a particular radius o curvature and center of curvature 6χ which is found b ordinary geometry methods. As shown in Figure 7, new hinge point 6χ will caus the lift platform 78, represented by line BL-BL (in it ground position), to move upwardly and gradually tilt an move through various intermediate positions until it reache the desired tilt position, as shown by line Bχ-Bχ having th desired tilt angle gamma prime. Further, raising of th lift platform will cause it to rotate out of its tilte position Bχ-Bχ back to a horizontal position when it reache maximum height, as shown by line Bn-Bg.

In a similar way, new hinge point 6χχ will cause th lift platform to assume positions B^-BL, Bχχ-Bχχ~, and Bg-Bg, as desired.

It should be understood that when using the new hing point 6χ, the effective length of guide arm 84 will have t be 5χ-6χ, and likewise, when using hinge point 6χχ, th effective length of guide arm 84 will have to be 5χχ-6χχ.

Again, it should be understood that if some degree o tilt is desired at the maximum height of lift, this can als be achieved using the same procedure as explained above.

That is, if the lift platform is tilted out of horizonta position BJJ-BH to some tilted position desired, at maximu height, this will result in a new position for 5jj, say 5 prime. Then, the three points 5L, 5χ, and 5H prime define new arc whose center say 6χ prime and radius of curvatur are found by ordinary geometry methods. In this case, th effective length of guide arm 84 will have to be 5χ-6 prime. It should be understood that any one of the hing points 4, 5, 6, or 7 may be relocated in the above manner.

It should be understood that, in actual practica applications, rather than having discrete hinge points, suc as 13, 13' and 13" in Figure 3 or 6, 6¹ and 6" in Figure 6, the base frame may be appropriately slotted along arc 15 i Figure 3 or arc 100 in Figure 6 and a known mechanis utilized that would allow the hinge point to be locked a any intermediate position along said slots.

In a similar way, when the guide arm links ar required to be adjustable in length, there are several know ways that this can be achieved. One way is to have link with extra hinge point(s) in addition to the normal 2 (on at each end). For example, a link may have an additiona boring, such that the effective length of the arm i adjusted by using this additional boring as the new hing point. Alternatively, the link may be telescopic and b either discretely adjustable or continuously adjustable. Naturally, it is absolutely essential to the safety, and also to prevent damage to the lift, that whenever a lif has a "right"(R) and a "left"(L) set of linkages and one of these is individually adjusted prior to the lifting of th vehicle, the other linkage must be adjusted in the same manner.

One simple, reliable* and inexpensive yet foolproof solution will be given by way of example. Consider a lift of the type shown in Figures 1, 2, and 3, and let us assume that a pair of guide arms as -48, Figure 1 is to be utilized. Let us further assume that two alternative pairs of hinge points 13 and 13" only are to be utilized to give either a straight lift or a lift that gradually tilts the vehicle. The - left and right guide arms 48 are made identical with a bush at their ends bored out to accept th shaft pins, as shown in Figure 8. These pins have the usual heads 93, and the shaft portion 90 is of the correct diameter and width to mate with the aforementioned lower bushes of guide arms 48. However, the two pins shown on Figures 8 and 9 that are supplied with the lift are not identical, as one has a hexagonal section stem 91, while the other has a round section stem 92 as shown. The lift base frame 22 would have suitable mating borings positioned with centers at 13 and 13", both left and right side to accept the stems of these pins. However, these borings are crossed from the left to the right side of the lift. For example, the right side boring at position 13 would be hexagonal, while the left side boring at position 13 would be round. Then, the right side boring at position 13" would be round, while the left side boring at position 13" would be hexagonal. It should be noted from Figures 8 and 9 that the round and the hexagonal stems of the pins are so sized that each will only be enterable into its own mating boring in lift base frame. Clearly, this solution will ensure that the lift operator never has one linkage set at hinge point 13, while the other is set at hinge point 13".

It should be here mentioned that the lift platform will vary from one design to the next as, for example, the lift in Figures 1 and 2 has supporting arms that are hinged and telescopic, while the lift in Figure 5 has a telescopically-adjustable platform. Irrespective of the type of arms or platform, a suitable means must be provided for locking said arms or platform against accidental movement. However, several such means are already known and are quite conventional. Similarly, a means must be provided for making sure that the automobile does not slide down the sloping platform or arms, off the lift. One well-known means is to employ an interchangeable set of "hands" (some with forks and some with pegs, etc.), instead of the fixed lift pads 42 of Figures 1 and 2, and other solutions are also known. While I have illustrated my invention by means o specific embodiments, it is to be understood that numerou changes and modifications may be made therein withou departing from the spirit or scope of the invention a defined in the appended claims.

Claims

WHAT IS CLAIMED IS;

1. Apparatus for selectively lifting and tiltin vehicles, comprising: a base support frame having first and second hinge points defining a first arm therebetween; a vehicle support platform having third and fourth hinge points defining a second arm therebetween; a third arm connecting said first and third hinge points; a fourth arm connecting said second and fourth hinge points; said frame, platform, first arm, second arm, third arm, fourth arm, and said first to fourth hinge points defining a parallelogram-type linkage for maintaining sai platform horizontal in all positions; lifting means for raising and lowering sai platform between a loading position and a raised positio wherein said platform is either horizontal or tilted; a fifth hinge point to be used instead of a selected one of said four hinge points by disconnecting th two arms from said selected one of said four hinge point and reconnecting said two arms to said fifth hinge point, with the length of one of said two arms being adjustable an the other arm remaining fixed in length, so that actuatio of said lifting means moves said platform from said loadin position to a raised position wherein said platform is at a angle.

2. Apparatus for selectively lifting and tiltin vehicles, comprising: a base support frame having first and secon hinge points defining a first arm therebetween; a vehicle support platform having third an fourth hinge points defining a second arm therebetween; a third arm connecting said first and third hing points; a fourth arm connecting said second and fourt hinge points; said frame, platform, first arm, second arm third arm, fourth arm, and said first to fourth hinge point defining a parallelogram-type linkage for maintaining sai platform horizontal in all positions; lifting means for raising and lowering sai platform between a loading position and a raised positio wherein said platform is either horizontal or tilted; a fifth hinge point to be used instead of selected one of said four hinge points by disconnecting th two arms from said selected one of said four hinge point and reconnecting said two arms to said fifth hinge poin with said two arms being adjustable in length, so tha actuation of said lifting means moves said platform fro said loading position to a raised position wherein sai platform is at an angle.

3. Apparatus for selectively lifting and tiltin vehicles, comprising: a base support frame having first and secon hinge points which define one side of a first four-side linkage, said first four-sided linkage having third an fourth hinge points; a vehicle support platform having fifth and sixt hinge points which define one side of a second four-side linkage; said first and second four-sided linkages bein rigidly connected together; lifting means for raising and lowering sai platform between a loading position and a raised positio wherein said platform is horizontal; a seventh hinge point to be used instead of selected one of said first, second, third, and fourth hing points by disconnecting the two arms from said selected on of said hinge points and reconnecting said two arms to sai seventh hinge point, with the length of one of said two arm being adjustable and the other arm remaining fixed i length, so that actuation of said lifting means moves sai platform from said loading position to a raised positio wherein said platform is at an angle.

4. Apparatus for selectively lifting and tiltin vehicles, comprising: a base support frame having first and •secon hinge points which define one side of a first four-side linkage, said first four-sided linkage having third an fourth hinge points; a vehicle support platform having fifth and sixt hinge points which define one side of a second four-side linkage; said first and second four-sided linkages bein rigidly connected together; lifting means for raising and lowering sai platform between a loading position and a raised positio wherein said platform is horizontal; a seventh hinge point to be used instead of selected one of said first, second, third, and fourth hing points by disconnecting the two arms from said selected on of said hinge points and reconnecting said two arms to sai seventh hinge point with said two arms being adjustable i length, so that actuation of said lifting means moves sai platform from said loading position to a raised positio wherein said platform is at an angle.

SUBSTITUTE SHEET

5. Apparatus for selectively lifting and tilting vehicles, comprising: a base support frame having first and second hinge points defining a first line; a vehicle support platform having third and fourth hinge points defining a second line; a first arm connecting said first and third hinge points; a second arm connecting said second and fourth hinge points; said first and second lines being non-parallel when said support platform is in a raised position; and lifting means for raising and lowering said platform between a loading position and a raised position wherein said platform is at an angle.

6. Apparatus in accordance with any one of Claims 1 and 2, wherein on one side of said frame, said selected one of said four hinge points has a first-shaped bore and said fifth hinge point has a second-shaped bore, and wherein on the other side of said frame, said selected one of said four hinge points has a bore having said second shape, and said fifth hinge point has a bore having said first shape, and further including only two pins having stems with said first and second shapes for being received within said first and second-shaped bores.

7. Apparatus in accordance with any one of Claims 3 and 4, wherein on one side of said frame, said selected on of said four hinge points has a first-shaped bore and said seventh hinge point has a second-shaped bore, and wherein on the other side of said frame, said selected one of said four hinge points has a bore having said second shape, and said seventh hinge point has a bore having said first shape, and further including only two pins having stems with said first and second shapes for being received within said first and second-shaped bores.

ESHEET