US50306A - Improved lifting-jack - Google Patents

Description

UNITED STATES PATENT OFFICE. f

H. S. SHEPARDSON, OF SHELBURNE FALLS, MASSACHUSETTS,'ASSIGNOR TO H. S. SHEPARDSON 85 OO., OF SAME PLACE.

IMPROVED LlFTlNG-JACK.

Specication forming part of Letters Patent No. 50,306, dated October 3, 1865.

To all whom it may concern.:

Be it known that I, H. S. SHEPARDsoN, ot' Shelburne Falls, in the'county of Franklin and State of Massachusetts, have invented certain new and useful Improvementsin Lifting- Jacks; and I do hereby declare the following to be a full, clear, and exact description ofthe construction and operation thereof, reference being had to the laccompanying drawings, making a part ot' this specification, in which- Figure l represents a side view ot the jack run down to its lowest position. Fig. 2 represents an edge view thereof; and Fig. 3 represents the jack as run up and locked bythe gear which moves it.

Similar letters ot' reference where they occur in the several n'gures denot-e like parts of thejack in all the drawings.

My invention consists in certain mechanism for running up thejack and forlocking it and its load when up by the same mechanism.

To enable others skilled in the art to make and use my invention, l will proceed to describe the same with reference to the drawings.

A represents the base ot' the jack, and B a permanent upright secured thereto.

O is the movable portion of the jack, and united to the stationary or immovable portion B by set-screws a passing through slots bin the part O and into the partB, so that the part O may move up and down on the part B. On the part B there is pivoted a toothed arc, D, to which a handle or lever, E, is attached, so that said arc may be readily turned by it; and upon the part Gis pivoted, as at c, an arm, F, that has a concave rack, d, upon it that can be thrown in and out of gear with the circular arc D, as may be required. When the jack is run down, as in Fig. l, the arm F swings back until it comes against the stud e, where it stops, and is held with its rack d in gear with the arc D. When the part O is run up with its load, as seen in Fig. 3, the arc D comes -against a stud or stop,j`, and in `that position,

the last tooth of the rack being in gear with the last Atooth of the are, the hand may be removed from the lever, and the part O will remain locked up until again let down by raising the lever E.

That thejack may be adapted to the raising of' carriages (to which purpose it. is most generally applied) and to the varying height of axles therein, the upper portion ot' the movable part O is stepped olf, as at g, and below these steps are a series ot' holes, h, into any one of which a pin may be placed, so that under almost any cireumstancesa single sweep ot' the lever E and its toothed arc D will raise the load and lock it up, as above stated, for any practical purpose.

For raising very heavy bodies or weights the teeth ot the arc, instead ot' having a radial pitch, as is common in gear-wheels, may be inclined more in a line under the Weight that it sustains, and the teeth orcogs (l ofthe arm F should be correspondingly inclined, and thus the superincumbent weight or pressure, instead ot tending to throw the arm ont ot' gear with the arc, would tend t0 hold them together, or at least render them passive.

Having thus fully described the nature, object, and purpose ot' my invention, whatIclaim therein as new, and desire to secure by Letters Patent, is-

In combination with the permanent portion B and the movable portion G ot' the jack, the toothed arc D and swinging toothed arm F, operating together for the purpose and in the manner substantially as herein described and represented. I

H. S. SHEPARDSON.

Witnesses:

. ARTHUR MAXWELL,

J. H. WILDER.

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