US718947A - Lifting-jack. - Google Patents

Description

PATENTED JAN. 20, 1903.

H. DEARBORN.

LIFTING JACK.

APPLICATION FILED JUNE 17, 1902.

30 MODEL.

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HENRY DEARBORN, OF PESCADERO, CALIFORNIA, ASSIGNOR TO EUGENE L. DEARBOR N, OF PESOADERO, CALIFORNIA.

LlFTiNG-JACK.

EPEGIFEGAEIION forming part of Letters Patent No. 718,947, dated January 20, 1903.

Application filed Tune 17, 1902.

To all whont it may concern.-

Be it known that I, HENRY DEARBORN, a citizen of the United States of America, and a resident of Pescadero, in the county of San Mateo and State of California, have invented certain new and useful Improvements in Lifting-Jacks, of which the following is a specification.

This invention is a lever-jack primarily devised for use in greasing wagons and other wheeled carriages,and comprises a novel linkwork by means of which I get great power or leverage, vertical action, and an automatic self-locking eifect.

In explaining my invention I shall refer to the accompanying drawings, which are integral herewith as a medium of illustration and in which I employ like reference characters to indicate like parts in the several figures.

Figure 1 is a side elevation of my invention, showing it in the lowered or released position of the jack with the actuating-lever vertically disposed. Fig. 2 is a rear elevation with the handle of the actuating-lever broken away to showa rearwardly-disposed ratchet and other detail. Fig. 3 is a view similar to Fig. 1, but showing the jack in its functional or raised position with the actuating-lever horizontally 0 disposed and its handle partly broken away.

Fig. 4 is a broken and enlarged side elevation illustrating the movable parts in a position intermediate between the two extreme positions shown in Figs. 1 and 3, respectively.

Fig. 5 is a front view looking from the left of Fig. 4.

The principal parts of my invention in the form here illustrated are a downwardly-inclined base A, a vertically-disposed lifting o ram or post 13, bent forwardly at its lower end to form a downwardly-pointed member B having the same inclination as the said base, links C and D pivotally securing this member 13 of the said ram or post and holding it parallel to the slanting portion of the base A, a lever E, pivoted at its lower end to the upper part of the base A rearward of said links, and a toggle-operating connection F, pivotally attached at one end to the said le vers E and similarly secured at the other end to the joint formed by the lower extremity Serial No. 112,096. (No model.)

of the member 13 of the ram or post and by the corresponding upper extremity of the lowermost link or links C.

As shown, the base of my improved liftingjack is composed of two vertical plates A A of metal, riveted together on the opposite faces of an intervening piece of wood board A and having outwardly turned bottom flanges A that are fastened by rivets or otherwise to a foundation-plate A I have illustrated this construction because it is so simple that it can be availed of anywhere, requiring no special manufacturing plant or facilities for its production. Let it be understood, however, that the mode of manufacture of the said base, as well as of the divers parts hereinafter described, can be varied in many particulars without departing from the principle or scope of my invention. The upper portion of this base A may be inclined at any suitable angle; but I prefer to have it at forty-five degrees to the level or horizon or one hundred and thirty-five degrees to the upright portion of the ram or post B, and consequently the thereto parallel member B of the latter will have the same incline.

The links 0 and D are preferably made in pairs, so as to grasp on opposite sides thereof the parts with which they are pivoted or hinged. These links are attached to the upper inclined portion of the base A and to the member 13* of the ram or post B by pivots G G and 1-1 1-1 (G G for C and H H" for D,) and they are arranged so as to admit of the free reciprocation of the said member above and forwardly of the said inclined portion of the base. The pivots G and H are at the same distance apart as the pivots G and H and the links C and D are of equal length in order always to maintain this member B at the same angle with the horizon in its upand-down movement-that is, so that the upward-and-downward action of the ram or post B shall practically be vertical. The length The means of actuation will presently be described.

A bifurcate portion E of the lever E (its lower end) is fulcrumed on the upper part of the base A oppositely to the toggle-joint or knee-joint formed at the articulation of the lower end of the bent member B of the ram or post B with the upper end of the links 0 by the pivot G .It is thus fulcrumed, preferably, at and by means of the pivot H, pertaining to the lower end of the links D, and it is linked with the said pivot G by means of the before-mentioned toggle-operating connection F, which consists of a pair of bars or rods engaged by G2 at their remote ends and likewise pivotally secured at their other ends to the said lever E by a pivot J, placed at a proper distance above the fulcrum H thereof.

By this toggle-joint arrangement it is manifest that the raising and lowering of the lever E varies the angle at G and hence reciprocates the member B which raises or lowers the ram or post B. As already understood, this part B of the ram or post B slants downward and is disposed above and parallei with the slanting edge of the supportingplates and board A A A of the base, and since the links 0 form various angles with the said part or member B by their kneelike action the latter will rock up and down in parallelism with the aforesaid slanting edge as the knee-angle becomes greater or less. I prefer to arrange the links 0 and D angularly with relation to the member 13*, so that the said links 0 and D or one of them are or is at right angles to the said member B when the lever E is in its intermediate position, as illustrated by Fig. 4:, that therefore when the lever E is horizontal the links 0 shall form an obtuse angle with the part 13*, thus elevating the ram or post B, as shown in Fig. 3, and that when the lever'E is vertical or up against the rain or post 13 the links 0 shall form an acute angle with the part B and thus bring the ram or post to its lowest position. The pivots G H, and J are all in a line and horizontally disposed with relation to each other when the lever E is in its horizontal position. at which position the bars, rods, or links F have drawn the pivot and angle G to its closest point toward the fulcrum H and raised the ram or post B to its greatest elevation. By dropping the lever a little below horizontal the lever manifestly becomes locked against the floor or ground, for which self-locking effect I arrange the pivots J, H, and G aforesaid at a properelevation on the base A.

To adjust the ram or post B so as to accommodate any desired height of object to be raised, I form one edge of the said ram or post with upwardly-trending ratchet-teeth K for the purpose of engaging and holding against any descending tendency an adjusting lifting-dog L, which dog is the means for contacting or grasping the object to be raised. This dog is provided with two opposing or holding pins M and N, transversely disposed with relation to the ram or post B, of which M is more elevated than N and engages the aforesaid teeth K,while N is on the opposite edge of the ram or post B and is made to impinge and be forced against said opposite edge as the ram or post and dog are forced up against the object to be raised, producing a self-locking ratchet-and-pawl device of convenient form,

the working of which is quite simple and re' quires no further explanation. I prefer to make the ram or post 13 of two parts,kept asunder, so as to form a longitudinal slot O,-by blocks P, placed at proper intervals and secured in their respective .positions by bolts or rivets Q. Within the said slot 0 the dogL acts and is laterally held secure. When the jack is fully released, the handle of the lever E comes into contact with and normally rests against the rear end of this dog L if the latter be at or near the position illustrated in the drawings, or, if much lower down, against the upper end of the ram or post B, thus checking the downward movement of the linkwork and connected parts along the slant of-the base A. The same effect is produced after the jack has been raised to its greatest elevation by swinging the lever E in the 0pposite direction to contact with the floor or ground on which the base A rests.

Although I prefer to make the links 0, D, and F in pairs, as above stated, it is obvious that single links similarly disposed would render substantially the same service; also, that the more important links are those marked D and F, respectively, the former coupling the bend of the member B of the ram or post B to the upper portion of the slanting base A and the latter likewise joining the point or lower end of the said member to the lever E. The links 0 are simply auxiliary and employed as a mechanical expedient to take up part of the strain in the use of the jack, particularly in lifting heavy weights. Let therefore the subjoined claims and their various clauses be interpreted in the light of this statement.

WhatI claim, and desire to cover by Letters Patent of the United States, is-- 1. In a lifting-jack, the combination of a base, a ram or post linked toand extending laterally at its lower end beyond its link connection with said base, and reciprocating means for said ram or post connected with its said laterally-extending lower end.

2. A lifting-jack comprising a base, a vertically-disposed ram or post having a forwardly-bent portion, and means for operating said ram or post comprising a linkwork including parallel links 0 and D pivotally secured to the base and the ram or post, the lower and upper pivots, respectively, of the links occupying inclined planes; substantially as described.

3. The combination, in a lifting-jack, of a base, a ram or post, a link D pivotally connecting the ram or post to the base, a lever,

and a link F pivoted at one end directly to the lever, and at its opposite end to the ram or post at a point outwardly beyond its link connection with the base; substantially as described.

4. In a lifting-jack, the combination with a base, of a vertically-disposed ram or post having a member parallel to the upper surface of said base, one or more links D connecting the base with said member, a lever adapted to stand up close to said ram or post, and one or more links F also interconnecting said member and the said lever at a suitable point above the latters fulcrum.

5. A lifting-jack consisting of a downwardly-slanting base, a ram or post having its lower end bent to conform to the slant thereof, one or more links connecting said member at its bend with the uppermost portion of said slanting base, and a lever fulcrumed on the base and thereabove also linked to said member at a point below its said bend.

6. A lifting-jack comprising a base having an inclined surface, a ram or post bent to conform to the incline of said base, links interconnectin g the ends of the bent portion of said ram or post with opposite parts of the base and holding said portion in parallelism with said inclined surface, a lever fulcrumed on the base-pivot of the link or links nearest the bend of said ram or post, a link connection coupling said lever above its pivot with the toggle-joint formed by the outer end of said bent portion and the farther link or links, and an adjusting lifting-dog on the ram or post; substantially as set forth.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

HENRY DEARBORN. n s.]

WVitnesses:

GEO. 0. Ross, F. H. THORPE.

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