US375769A - Lifting-jack - Google Patents

Description

UNITED STATES PATENT OFFICE.

GEORGE S. RIOKARD, OF COLUMBUS, OHIO.

LlFTlNG-JACK.

SPECIFICATION forming part of Letters Patent No. 375,769, dated January 3, 1888.

Application filed September '7, 1887. Serial No. 249,023. (No model.)

To all whom it may concern:

Be it known that I, GEORGE S. RICKARD, a citizen of the United States, residing at Columbus, in the county of Franklin and State of Ohio, have invented a certain new and useful Improvement in Lifting-Jacks, of which the following is a specification.

My invention relates to devices for lifting heavy objects, and has particular relation to that class known as vehicle-liftingjacks.

The objects of my invention are to provide a neat, simple, and effective lifting-jack by means of which heavy bodies may be readily and easily elevated to different heights, and to so construct the same as to prevent the binding of the elevatingarm against its standard when the former is being raised. These objects I attain in the manner illustrated in the accompanying drawings, in which Figure 1 is a side elevation of the liftingjack. Fig. 2 is a vertical section taken through the center of the same. Fig. 3 is a perspec tive view of one of the guide-blocks, and Fig. 4 is a plan view of the device.

Similar letters refer to similar parts throughout the several views.

A represents a vertical standard provided with a suitable base, B, with which it is firmly connected in any well-known manner.

0 represents a vertical lifting-bar, having its front side provided with a series of upwardly-inclined notches, c, and having cut inwardly from its rear side a T-shaped groove, (1, said groove extending the full length of the arm. Formed in the front surface of the standard A is a groove, a, corresponding with the groove (1.

F represents a metallic guide-block having two opposite sides grooved, as shown, in the form of an I-beam, and having a screw-hole, f, formed through its center at right angles with said grooves. This block F is secured to the bar 0, as shown, by inserting one of its halves into the similarly-shaped groove d until at a short'distance from the bottom of the arm, at which point it is securely fixed by means of a screw made to pass through the screw-holef and into the arm. The standard and arm may then be connected by raising the latter above the former and inserting the projecting half of the block F into the upper end of the groove a and allowing the arm to slide down until it rests on the base B. A block, F, corresponding with the block F, is then inserted within the H-shaped opening formed by the joining of the grooved parts of the standard and arm until at a short distance below the upper end of the standard, where it is fixed by means of a screw made to pass through the standard from the rear side into the screwhole of the block F. By this construction it will be seen that when the liftingbar 0 is raised or lowered, as hereinafter described, the block F will travel in the groove (1, and the groove (1 form a track for the block F.

Pivoted by means of a pivot-pin, s, on opposite sides of the upper portion of the standard are two metallic lever-arms, H, each of which in front of its pivotpoint is curved slightly upwardly, and has its rear portion curved rearwardl y and downwardly, as shown. The rear ends of the lever-arms H are secured in any suitable manner to one end of a leverhandle, it. To the upper or front ends of the arms H are pivoted, respectively, the corresponding ends of two parallel arms, I, the latter being connected at their outer ends by means of a transverse pin, i.

In order to elevate an object by my device it is necessary to first place it so that the upper end of the elevating-bar O is beneath the object to be raised. Said arm may then be elevated by raising the lever-handle until the cross-pin i may be inserted within the-desired notch c, and then forcing the lever down until in a position parallel, or nearly so, with the standard, as shown in Fig. lot the drawings. The lever having been brought to this position, it will be seen that the point of connection between the leverarrns and the arms I is in rear of the point of connection between the said levenarms and the standard, thus pre venting the vertical strain caused by the weight of the body being elevated from forcing the lever-handle up again.

I am awarethat it is common to lock connected parts by throwing the strain back of the lever-pivot point, and that the parts of lifting-jacks have been fitted together by means of grooves and tongues; but myinvention differs from these in securing a direct vertical leverage through the lever and arms I, and in arms H, having handle h, said arms being pivthe use of the grooved guide-blocks F F, by oted to the standard, arms I, having cross-pin means of which an easy and even bearing is i, the grooved and notched elevating-bar G, formed between the standard and elevatingand the block F, substantially as and for the 5 arm. purpose specified. V

Havin now fully described my invention What I claim, and desire to secure by Letters GEORGE RIGKARD' Patent, is In presence of In a 1iftingjack, the combination of the JOHN M. TIBBETTs,

[o grooved standard A, the guide block F, lever- G. W. DEVERE.

Images