US70908A - Improvement in carbiage-jaci - Google Patents

Description

J. B. SMALL.

Lifting Jack. X No. 70,908. Patented Nov. 12, 1867.

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JOSIAH B. SMALL, OF no STON, MASSACHUSETTS. Letters Patent No. 70,908, dated November 12, 1867.

IMPROVEMENT 11v CARRIAGE-JACK.

TO ALL PERSONS TO WHOM THESE PRESENTS MAY COME:

Be it known that I, JOSIAH B SMALL, of Boston, in the county of Suffolk, and State of Massachusetts,

have invented a new and useful Improvement in Carriage-Jacks and do hereby declare the same to be fully described in the following specificatiom and represented in the accompanying drawings, of which- Figure 1 is a side elevation, and I Figure 2 an end elevation of my improved jack.

, 'In the carriage-jack shown in' the United States Patent No. 36,587, the lever D is connected with the notched bar 0 by means of links F, but the notched bar, while being operated, turns in a curve on a centre pin, and thus causes a lateral movement, as well as a vertical movement, of the carriage while in the act of being raised by the jack.

In the carriage-jack represented in the United States Patent No. 37,902, the notched slider is applied to its standards so as to play vertically between them, and is moved by a cammed lever, which is very objectionable on account of the friction and wear occasioned by it.

In the jack shown in the United States Patent No. 42,050, the notched slider moves on an inclined plane,

and is moved b-ya cammed lever acting against a friction-rollen' This jack has the disadvantage of producing lateral motion of the carriage, or, in case the carriage does not move, the axle, while being elevated, is liable to slip off the step of the slider. v

There is alsoanother jack, recently invented by C. H. Paine, and for which he filed in-thc Patent Oflice an application for a patent, on .or about the eighth day of August, A. D. 1867 This latter jack has a lever jointed tovits slidc-bar, and also to a toggle jointed to the base of the standard, to which such slide-bar is connected. By pullingup the longer arni'ofthe lever, the slide-bar will be elevated vertically. The great disadvantage of this latter jack is that the efl'ort made to raise the longer arm of the lever has'a tendency to throw the whole jack and carriage forward, forywhen thc lever is at'an angle of forty-five degrees to the horizon,

one-halt" thelifting force bearing on the lever tends to move the jack and carriage horizontally. It is very desirable-to avoid this it possible, or, in other words, to raise the jack vertically without at the same time prodncing any lateral movemeut'of it. This I accomplish by my jack, in which the notched slider A has its shank a arranged between and against two' upright-posts, B' O, erected on a base-board, D. These posts are connected near their upper ends by two horizontal bars, E E,-and there isa stud, a, extended from the inner *sideof one of the posts, and into a groove, 6, made'in the lower part of the shank a. Thus,'by means of the two posts,

their connection-bars E E, and the stud a and groove 6, the notched sliderwill be guided invertieal directions- I while it may be in the act of being elevated. A, toggle, F, is applied to each side of the shank, and so as-to turn on a pin, a, projecting from the latter. The two toggles hang down from their supports, and are jointed at their lower ends to the shorter arms ererof a furcated lever, G, which spans the rear post, and turns on a fulcrum or bolt, f, extending through the arms and the post. I

When the longer arm of this lever is seized and forced downward, the toggles and the shorter-arms of itsprongs will operate a s sets 0t toggles to effect the elevation of the notched bar, and when the lever may have descended so as to carry the centre of its joint, with each toggle, a little back of a straight line extending from the upper'joint of the toggl'e to the fulcrum of the lever, the inner end or part k of the lever-fork will bring up against the post, and serve as a stop to hold the notched slide up under the-weight or downward pressure of the carriage upon it.

Thus, in my improved jack, I combine the advantages of vertical movement of the slider, and downward movement of the lever to climb the same, with the advantage of the toggles over the cammed lever, or the same and a friction-roller. make a very simple and eflieient jack; therefore I make no claim to any of the other carriage-jacks hereinbefore mentioned; but 7 What I claim as my invention is My improved carriage-jack, as constructed with its notched lifter or slider, arranged with guide-posts in manner as described, and as having two toggles and a forked lever, and a stop, it, thereof, arranged and combined together and with it and one of the posts, in manner as specified.

- JOSIAH B. SMALL.

Witnesses:

R. H. EDDY, F.. P. HALE, Jr,

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