J. L. WHITE July 4, 1950 BUMPER JACK Filed July 7, 1945 FIG-2 FIG- II zu 43 l 2 I llll .i. m n a H a I 2FII|IIIT JOHN L.WHITE' IN VEN TOR.
\ ,47'70PNE Y Patented July 4, 1950 BUMPER JACK John L. White, Dallas, Tex., assignor to Robert C. Brown, J r., Highland Park, 111., as trustee Application July 7, 1945, Serial No. 603,647
Claims. (Cl. 254-107) This invention relates to lifting jacks and more particularly to a type of lifting apparatus known as a bumper jack.
The principal object of the invention is to providean inexpensive but effective and durable jack,
adapted primarily to lift vehicles for tire changes and other purposes by engaging the bumper of a vehicle and by virtue of a pair of spring pressed, circular elements or washers, loosely mounted on parallel uprights, together with a handle actuated oscillatable member, constrained'to alter- :nately rock the said washers on said uprights,
a housing embracing said elements, having means for engagement under the object to be lifted, is caused to be moved upwardly on said uprights to lift said object.
Another object of the invention is to provide a lifting jack consisting of the few working parts named, but supplemented by a releasing lever located conveniently near the operating handle, having the function to center the washers on the uprights and, through the joint action of the said lever, springs and handle, the said housing isreleased to the weight of the object lifted to lower the latter.
With the foregoing objects as paramount, the
invention has further reference to certain features of accomplishment which will become apparent as the description proceeds, taken in connection with the accompanying drawings where- Figure 1 is a perspective view of a jack constructed according to the invention.
Figure 2 is an elevational view, fragmentarily vshowing the upright support and showing the housing in vertical section.
Figure 3 is a plan view in transverse section, taken on line 33 on Figure 2, a portion of the oscillatable shaft being broken away.
Figure 4 is a side elevational view, and
Figure 5 is a detail perspective view of the oscillatable shaft for actuating the washers.
Continuing with a more detailed description of the drawing, reference is primarily made to Figure 1 wherein numeral I0 denotes a stand formedbybending a rod or tubing of suitable diameter to define an elongated U-shaped member con arm ll;
of a rectangular plate or strip l5 at the top and bottom, to which the inwardly turned edges of the plates M are spot welded at appropriate points. Thus, a rigid body, having open sides is provided and is apertured to slidably receive the uprights H.
The plates [4 of the housing I3 are further provided with aligned slots below their midsections to accommodate a lifting arm consisting of two fiat pieces of metal 56, welded together intermediate their ends and shaped to define a lifting arm H. The pieces l6 extend entirely through the housing l3 and their rear ends are bent reversely at l8 and flattened against the outer surface of the plate I I opposite the lifting A shoulder 19 (Figure 4) is formed in the under edge of the arm I! Where it enters the housing I3 to serve as an abutment, reinforcing the arm I1 when a load is imposed thereon, the flattened ends 18 of the plates l6 preventing them from being drawn from their positions in the housing under stress of a load.
To raise the housing I3 on the uprights l l' with a series of successive movements, a climbing ring or washer 20 is mounted on each upright and whose central opening is slightly larger than the diameter of the uprights. Bearing. upon the underside of each washer 2B is a coiled spring 2|, surrounding the upright therebelow. The wash- .ersZU are adapted to be alternately rocked on their uprights by means of an oscillatable stub shaft 22. This shaft has a reduced end 23, extending through an aperture in the housing wall 14 next adjacent the lifting arm ll. 'The opposite end of the shaft extends through an opening 24 in the opposite wall of the housing and, contributing to the structural economy and ease of assembly of the device, no means other than the washers 20, reposing in recesses 25 in the shaft 22, is required to hold the latter against longitudinal displacement in the housing.
The recesses 25 (Figure 5) are arranged longitudinally in shaft 22 on opposite sides thereof and in which the edges of the washers '20 are received in the manner shown. Sufficient clearance is allowed the edges in the recesses 25 to prevent binding thereof as the shaft 22 is oscillated.
One end of the shaft 22 is formed into a flattened pin 26, which is received by a correspondingly shaped recess in the end of a handle 21, the latter consisting of flat metal and is readily removable from the pin 26.
In operating the jack, the arm I! is disposed under the object to be lifted, such as the bum-per of an automobile and the lower end of the stand I I] is set into a base consisting of a channel member 28 whose sides 29 are bent slightly inwardly to more nearly equal the diameter of the uprights I i in their relative spacing. The base prevents the stand from sinking into the ground and from sliding from under the load and a pin (not shown) inserted in holes a in the sides of the channel member 28, prevents displacement of the stand longitudinally of the base.
As the handle 21 is reciprocated vertically, the shaft 22 is oscillated, which action rocks the washers 2i on the respective uprights H alternately. For example, viewing the assembly as it appears in Figure 2; the shaft 22, is being rotated in a counter-clockwise direction, will raise the inner edge of the washer 2B-at the'right while the companion washer assumes-the weight of the load imposed on the housing I?! by the supporting or lifting arm l1. As the change is made in the position of the washer on the right, the spring 2i thereunder retains the same and shifts it to ahigher level on the upright. When the shaft 22 is rotated in the opposite or clockwise direction, the other washer is similarly actuated, the washer on the right being new effective to support the load and the spring under the active washer "functioning to elevate thesame. Oscillation of the handle and consequent rocking of the washers is continued until the object has been raised to the desired height.
To lower the housing It on the uprights I I, a release lever 36 is provided which is fastened, preferably by welding, to one of the washersizfl. It will be observed, especially in Figure 3 thattthe free end of the lever as is bent at right angles to overlie the handle 21 in order that it may be engaged by the thumb of the same hand used to actuate the handle. By pressing downwardly with the'thumb on the lever 30 to bring the washer to which it is attached into a horizontal .position as the handle 2? is gradually lowered to such'position as to dispose the companion washer also in a horizontal plane, a fixed angle member 3|, de-
pending from the upper end of the housing I 3will be engaged by the said companion washer, which latter, it will be understood is under the normal pressure of the spring 2! therebelow. With both washers now in a horizontal plane, they no longer function to support the housing l3, which latter,
under the weight of the load supported by arm l1;
falls downwardly with the load.
iMa-nifestly, the construction as shown and described is capable of some modification'and such modification as may be construed to fall within the scope and meaning of the. appended claims is also considered to be within the spirit and intent surrounding said uprights below-and bearing against said washers, a housing embracing said washers and springs, a shaft journaled in the walls, of said housing to oscillate between said washers and having recesses receiving the edges of said washers, a load lifting arm protruding from one wall of said housing, meansfor oscillating said shaft to actuate said washers to "eleclimbing, members upwardly.
4 vate said housing on said uprights and means for releasing said washers from frictional engagement with said uprights to lower said housing thereon.
2. In a lifting jack, a pair of uprights, a housing slidable longitudinally on said uprights and having a load supporting arm protruding therefrom, a pair of cooperating washers rockably mounted on said uprightsjjinjsaidhousing, stabilizing springs bearing against the undersides of said washers, means journaled in said housing between "said washers and engageable with each for alter- :nately rocking the same to advance said housing along said uprights, means for actuating said latter means and means for disposing and holding said washers in a plane at right angles to the axes of said uprights to release and lower said housing on the latter.
'3.In a lifting jack, a pair of uprights, washers rockably mounted on said uprights, a spring bearing against the underside of each of said washers, a housing for said'springs andwashers, having a load engaging arm thereon, means oscillatably mounted in said housing eifective to alternatev frictional engagement of saidwa'shers'and their respective uprights to advance said housing on said uprights andmeans for releasing said washers simultaneously from said uprights to lower said housing thereon. 1
v4. A lifting jack comprising a base, a U-shaped member including parallel uprights, fastening means fixed to the base extending between the uprights, a housing slidably mounted on the uprights and having'a load bearing member, cooperating friction climbing members rockably embracing the uprights within the housing, asubstantially straight load transmitting sha'ftxjournaled in the housing between the uprights and shaped to'engage the climbing members, whenbya load on the housing may be transmitted directly to both-climbing members by the 'load transmitting shaft, and springs for urging'the 5. Alifting jack-comprising parallel spaced-um rights, a housing slidably mounted on the uprights, a load bearing member rigid with the housing, cooperating friction climbing members REFERENCES orrnn The following references are of record infthe file of this patent:
UNITED STATES PATENTS Number Name Date 557,501 Ennis Mar. 31, 1896 991,965 Flint May 9,1911
1,033,? 15 Luker July 23,1912
Grover Apr. 29,1913