US253300A - Lifting-jack - Google Patents

Description

(No Model.)

' F. LEHMAN.

LIFTING JACK. No. 253,300. Patented Feb. 7,1882.

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Lay-i WITNESSES UN rra a ATENT LlFTlNG-JACK.

SPECIFICATION forming part of LettersPatent No. 253,300, dated February 7, 1882.

Application filed December 2, 1881. (No model.)

To all whom it'may concern:

Be it known that I, FREDERICK LEHMAN, of Milwaukee, in the county of Olackamas and State of Oregon, have invented certain new and useful Improvements in Lifting-Jacks; and I"do hereby declare that the following is a full, clear, and exact description of the invention, which will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, which form a part of this specification.

Figure l is a perspective view. Fig. 2 is a vertical sectional view. Fig. 3 is a vertical section on the line 00w, Fig. 2. Fig. 4 is a horizontal section on the line y y, and Fig. 5 is a horizontal section on the line 2 2.

Corresponding parts in the several figures are denoted by like letters of reference.

This invention relates to lifting-jacks to be used for various purposes for which great exertion of power is required, such as raising houses, pulling stumps, and the like, and it consists in certain improvements in the construction of the same, which will be hereinafter fully described, and particularly pointed out in the claims.

In the drawings" hereto annexed, A represents an upright supported upon a suitable base, B, and having a vertical slot, 0, in which the GXiJBllSlOILSlldG. D works, as will be hereinafter described. A metallic collar, E, is arranged at the upper end of the slot in upright A, to guide the slide D, and the latter is provided near its lower end with laterally-projecting studs F, working in recesses or grooves Gin the sides of slot 0.

To the upper end of slide D is swiveled a plate, H, having its ends bent upward and pointed or sharpened to form a bearing for the weight to be raised, or to enable. a chain or rope to be made fast for the same purpose. The lower end of slide D is formed with a hook, I, projecting through the slot U, which said hook may likewise be used to support the weights to be raised.

To the rear side of the upright A are secured a pair of curved or semicircular arms or brackets, J J, between which is pivoted thehand-lever L. At a short distance from its fulcrum the said hand-lever is con nected by pivoted rods K with the outer end of a lever, M,

pivoted between a pair of rods or hangers, N

N, projecting downward from a bolt, 0, secured transversely at the upper end of upright A, and upon which the said rods or hangers are pivoted.

I? is a sleeve or collar somewhat larger in circumference than the slide D, which it encircles, as shown. Said sleeve, which may be termed the lifting-sleeve, is provided with rearward-projecting arms Q, to which the inner end of the lever M is pivoted.' The sides of the sleeve 1? are provided with laterallyprojecting pins orstudsRRprojectingthrough slots S S in the sides of upright A, and con nected to springs T, by which the said sleeve P is thus forced automaticallyin a downward direction. Encircling the slide D above the lifting-sleeve is a similarly-constructed holding-sleeve, U, which is pivoted to the lower end of an arm, V, pivoted upon and extended downward from the transverse bolt 0. The sleeve U is provided with pins or studs W, projecting laterally through slots X in the sides of the upright, and connected to springs Y, by which the sleeve U is forced in adownward direction.

Z is a latch or lever pivoted to the side of upright A, and provided with a thumb-piece, A, and a pin, B, projecting inward through one of the slots X and bearing against the under side of sleeve U, which may thus, by pressure upon the thumb-piece A, be raised, as will be presently described.-

The operation of myinvention will be readily understood from the foregoing description; taken in connection with the drawings hereto annexed. By operating the hand-lever the lifting-sleeve is first slightly tilted so as to clamp the extension-slide and hold it by friction while being raised for the distance the said sleeve is capable of being raised-by a single downstroke of the hand-lever. the latter is being raised for a repetition of the operation the gripe of the lifting-sleeve is released and the slide D is clamped by the "holding-sleeve U, which is thrown into en- When the slide D is released and said slide permitted to drop by its own weight into the slot or socket in upright A.

Having thus described myiuvention, I claim and desire to secure by Letters Patent of the United States- 1. [n a lifting-jack, the combination of the upright A and slide D, the sleeves P U, having arms or studs projecting through slots in upright A, the springs T Y, and lever mechanism, substantially as described, for operating the slide D through the medium of sleeve P, all arranged and operating as herein described.

2. In a lifting-jack, the combination, with FREDERICK LEHMAN.

Witnesses:

W. W. GIBBS, P. A. MARQUAM, Jr.

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