US2543308A - Portable jack - Google Patents

Description

E. WOLF PORTABLE JACK Feb. 27, 11951 2 Sheets-Sheet 1 Filed Nov. 13, 1945 R O T N E v m Edward wolf ATTORNEYS E. WOLF PORTABLE JACK Feb. 27, 1951 2 Sheets-Sheet 2 Filed Nov. 13, 1945 INVENTOR Edward wolf mm m ATTORNEYS Patented Feb. 27, 1951 UNii hD S'i'A'iiEfi @FFEQE PORTABLE JACK Edward Wolf, Stockton, Calif.

Application November 13, 1945, Serial No. 628,119

This invention relates in general to an improved portable jack of the wheel-supported type used in garages, automobile storage or parking establishments, or the like, for the purpose of readily and conveniently moving automobiles from one place to another without starting the engine thereof.

In particular the present invention represents improvements over the device shown in U. S. Patent No. 2,254,055, dated August 26, 194d.

One object of this invention is to provide, in a portable jack which includes a whee supported, hand controlled frame having a jack. unit on one end thereof, novel power actuated mechanism arranged to operate the jack unit and drive the wheel supported frame along the floor, selec tively.

Another object of the invention is to provide a portable jack, as above, wherein the power mechanism for operating the jack unit includes a fluid pressure actuated power cylinder coupled in novel manner to the jack unit; there being an operator-controlled fluid pressure supply system connected to the power cylinder whereby the operator regulates the position of the jack unit.

A further object of the invention is to provide a portable jack, of the type described, wh rein the drive mechanism for the wheel supported frame includes a driven axle unit arranged to impart a semi-differential drive to the transversely spaced front wheels of the device so as to facilitate manipulation thereof when said wheels are being driven.

A further object of the invention is to provide simple and inexpensive device, and yet one which will be exceedingly effective for the purpose for which it is designed.

These objects are a complish d by means of such structure and relative arrangement of parts as will fully appear by a perusal of the following specification and claim.

In the drawings similar characters of reference indicate corresponding parts in the several views:

Figure 1 is a side elevation of the improved portable jack.

Figure 2 is a rear end elevation of the jack.

Figure 3 is a sectional plan view of the jack.

Figure 4 is an enlarged fragmentary cross section showing the front wheel drive assembly.

Figure 5 is a diagram of the valve-controlled fluid pressure system for the power cylinder.

Figure 6 is a diagrammatic plan view of modifled drive mechanism.

1 Claim. (01. 254-2) CPI Referring now more particularly to the characters of reference on the drawings, and at present to Figs. 1-4 inclusive, the improved portable jack comprises an elongated, substantially horizontal frame, indicated generally at i; said frame being cast in one piece and includin transversely spaced, forwardly projecting side beams 2, and a platform 3 at its rear end. At its forward end the frame i is supported by a pair of transversely spaced floor engaging wheels 6 carried on a cross shaft 5 and adapted to be driven in the manner hereinafter described. Adjacent the forward end of the platform 3 the frame l is supported, on opposite sides, by outboard caster wheels 6.

At its forward end the frame 5 supports a jack l which includes a longitudinally extending, vertically disposed parallel linkage 3 pivotally supporting an automobile engaging pad 9 on its forward end. Adjacent its inner end the parallel linkage 8 is pivotally connected between the side beams 2, with the uppermost one of the links in the form of a bellcrank having a depending rear leg it.

A fluid pressure actuated power cylinder H is mounted lengthwise between the side beams 2 adjacent the rear ends thereof and said cylinder includes a forwardly projecting piston rod l2. At its forward end the piston rod is connected to a cross head unit it which includes rollers M on opposite sides, and which rollers ride in corresponding, inwardly facing channels iii amxed to the innermost faces of the side beams 2 whereby the cross head unit 53 is guided for movement in a substantially horizontal plane. A connecting rod i6 is pivotally connected between the cross head unit it} and the lower end of the bellcrank leg iii of the parallel linkage 8.

The piston rod it of the power cylinder H is normally retracted, and at which time the parallel linkage a is in a down position so that the automobile engaging pad 8 is lowered. How ever, when the cylinder H is actuated to advance the piston rod l2 and connecting rod it, the leg id is forcefully swung forwardly, resulting in upward swinging of the parallel linkage 8 and elevation of the pad e for the purpose of raising an automobile under which the pad is disposed.

The power cylinder I i is actuated through the medium of a fluid pressure system which will hereinafter be described.

An air-cooled type, relatively small gasoline engine H is supported above the platform 3 by a .U- shaped pedestal it open lengthwise of the device, and through which pedestal a longitudinal countershaft l9 extends; said countershaft being supported from the platform 3 by suitable bearings. The countershaft IQ is constantly driven from the engine i2 by a pulley and. belt unit, indicated generally at 20; said unit including a bottom pulley 2! fixed on the countershaft l9.

The countershaft i9 is supported for limited axial shifting movement, which is accomplished through the medium of a cam-type shifting assembly 22 mounted on the rear end of the platform 3 in cooperative relation to the corresponding end of said countershaft I9. The shifting assembly 22 includes a lever 23 operative by a pull link 24 from a hand grip 25 connected to the top of an upstanding, inverted U-shaped steering handle 26 included in the device at its rear end.

On its face the bottom pulley 2| is formed with a friction disc 2? adapted for movement to and from driving engagement with a friction wheel 28 slidably splined on a cross shaft 29 ahead of said bottom pulley 2!. The friction wheel 28 is adjustably positioned on the cross shaft 29 by means of a shifting device 30 operated by a shifting lever assembly 3! supported in a suitable manner between forwardly and downwardly inclined braces 32 which stabilize the handle 26.

By advance of the countershaft it through the medium of the cam-type shifting assembly 22, the friction disc 2'! is brought into driving engagement with the friction wheel 23, causing rotation of the cross shaft 29; such rotation being reversible by shifting said friction wheel 28 to one side or the other of the axis of the friction disc 21.

The countershaft 29 is connected, in driving relation and by means of a sprocket and chain unit 33, with an endless, sprocket-supported drive chain 34 which extends along one of the side beams 2 beneath a chain guard 35.

At its forward end the endless drive chain 34 extends about a sprocket 38 fixed on the cross shaft inwardly of one of the wheels 4. A semidifferential drive is provided between the shaft 5 and the wheels 4 in the following manner:

A collar 37 is fixed on the shaft 5 adjacent the wheel 4 opposite the wheel corresponding to the sprocket 38, and lugs 38 project from said sprocket and collar, respectively, for engagement with other lugs 39 on the wheels 4. It will thus be seen that when the endless chain 34 is driven to rotate the sprocket 35 and cross shaft 5, each of the wheels 4'- is driven by engagement of the corresponding lugs 38 and 39, and yet said wheels may turn to right or left on the floor without any skidding action thereof.

The fluid pressure system for the power cylinder comprises the following:

A pump 49 is mounted on the platform 3 to one side of the countershaft IS and is driven by another countershaft 4! adapted to be connected, through the medium of a. clutch 42, and sprocket and chain unit 43, with said countershaft if); the clutch 42 being controlled by the operator from adjacent the handle 26 by means of a shifting lever assembly 44.

The piping system is shown diagrammatically in Fig. 5, and includes a pressure feed conduit 45 which leads from the pump 46 to the power cylinder H; fluid being supplied to the pump 46 from a tank 46 through a supply conduit 41. The tank 46 may be located at any convenient point on the device, and in the present embodiment is suspended beneath the platform 3.

Upon operation of the pump, fluid under pressure feeds through the conduit 45, including a check valve 48 interposed therein, and thence passes to the cylinder H in actuating relation to the same, causing elevation of the jack unit in the manner previously described. When the pump stops the check valve 48 closes and the jack unit remains elevated until the cylinder l I is released, as follows:

A relief conduit 69 leads from the conduit between the check valve 48 and cylinder H to connection with the supply conduit 41 between the pump ll] and tank 46; there being a normally closed hand valve 59 interposed in the relief conduit 49. The hand valve 50 is controlled by a hand lever B! disposed adjacent the handle 26. When the cylinder H has been actuated to raise the jack unit, it can thereafter be released by bleeding back the pressure therefrom through the relief conduit 49 upon opening of the hand valve 50, whereupon the fluid pressure delivers back to the tank 46.

To summarize, the above described portable jack is manipulated by an operator as follows:

The operator grasps the upstanding handle 25 and rolls the device under an automobile until the pad 9 is in correct position. Thereafter the shifting iever assembly i l is operated to cause driving of the pump 10, with resultant raising of the jack unit to desired height, whereupon drive of the pump is stopped by release of the clutch 42. Thereafter the hand grip 25 is operated to cause driving engagement between the friction disc 22' and friction wheel 28, the latter having first been set in forward or reverse driving direction. The drive is then imparted to the front wheels 4, in a direction to move the jackedup automobile. Steering of the portable jack, and the automobile supported thereby, is accomplished by the operator through manipulation of the handle 28.

In Fig. 6 there is illustrated a modification of the drive which may be employed between the engine and the sprocket and chain unit 33 In this embodiment the engine drives a pulley 5! on an axially immovable countershaft 52 journaled on the platform. Between the pulley 5! and the sprocket and chain unit 33 there is interposed a manually engageable clutch adjacent the pulley 5i, and a bevel-gear type reversing unit 5 3 is connected between said clutch and the sprocket and chain unit 33. The pump as would be driven from the countershaft 52 in the same manner as it is now driven from the countershaft I9, including a sprocket and chain unit 55 and a manually engageable clutch 56.

From the foregoing description it will be readily seen that there has been produced such a device as substantially fulfills the objects of the invention, as set forth herein.

While this specification sets forth in detail the present and preferred construction of the device, still in practice such deviations from such details may be resorted to as do not form a departure from the spirit of the invention, as defined by the appended claim.

Having thus described the invention, the following is claimed as new and useful and upon which Letters Patent are desired:

A portable :Eack comprising an elongated wheel supported frame, an engine on said frame, a clutch controlled means for selectively placing certain of the wheels supporting the frame in or out of driving relation with the engine whereby to allow the frame to be driven from point to point, an upstanding rigid steering handle on the frame at one end thereof, a lift jack unit on the frame at the opposite end thereof. a fluid pressure actuated power cylinder mechanism connected in operative relation with the jack to effect the raising of the jack when pressure is admitted to the cylinder, and a fluid pressure system for supplying fluid under pressure to said cylinder, such system comprising a pump, clutch centre d means for selectively placing the pump in out of driving relation w th the engine, a fluid supply reservoir, a condr t lcading from the reserve-1r to the intake side oi the pump, a conduit leading from the outlet side of the pump to the power cylinder, a check valve in the latter conduit operative to pr vent hack pressure from the cylinder through the pump, a third conduit leading from the second named conduit at a point between the cylinder and check valve and. hence to the reservoir, a con trol valve in the third named conduit which valve may be normally maintained in closed position while th pump is connected in driving relation with the engine and after disconnection therewith, and while the jack is in raised position, whereby to hold. the jack in raised position while allowing the engine to be then conn cted in driving relation with the driven wheels to transport any object supported on the jack from point to point with the travel of the frame, a

6 manually operable lever connected in operative relation to the control valve and extending to a position adjacent the steering handle, and a separate operating means for the respective clutch controlled means and each including an operating handle disposed adjacent the steering handle.

EDWARD WOLF.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 15 Number Name Date 99,56? Haussknecht Feb. 8, 1870 1,232,949 Hollis Apr. 9, 1918 1,895,583 Manley May 19, 1931 1,813,429 Sexton July '7, 1931 1,953,670 Cochin Apr. 3, 1934 2,254,055 Wolf Aug. 26, 1941 2,299,159 Kennedy Oct. 20, 1942 2,384,059 Wolf Sept. 4, 1945 FOREIGN PATENTS N umber Country Date 442,148 Great Britain Feb. 3, 1936

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