US1020879A - Lifting-jack. - Google Patents

Description

G. R.- BOOTH.

LIFTING JACK.

APPLICATION FILED APR. 1, 1911.

Patented Mar. 19, 1912.

[NI ENTOR f K. M

A flu mg! UNITED srairns PATENT OFFICE.-

G-LEIN' RUSSELL BOOTH, OF GHANA. ILLINOIS.

LIFTING-J'ACK.

To all whom it may concern.

Be it known that I, GLEN It. Boo'rir, a resident of Ghana, in the county of Ogle and State of Illinois, have invented certain new and useful Improvements in Lifting Jacks; and I do hereby (itjtiltii't. the following to be a full, clear, and exact description of the invention, such as will oi'nihle others skilled in the art to which it pertains to make and use the same.

This invention relates to lifting jacks adapted for raising the axles of automobiles, or other weights.

The main object of the invention is to provide a simple and etiicient. construction which in one adjustment raises the load on operation of the handle, and. in another adjustment lowers the load on like operation of the handle.

The invention consists in the construction hereinafter described and particularly pointed out in the claims.

In the accompanying drawing which illustrates the invention and forms a part of the specification, Figure it is a side elevation of the jack, a side cover-plate being broken'away; Figs. 2 and 3 show a holding pawl, and a lifting pawl; Fig. 4 is a view showlng means for stopping the lifting bar at a predetermined elevation; Fig. a shows a spring bearing.

Numeral 1 denotes the standard of a jack having a box or box-like enlargement 2, one side of which has a removable cover 3, said box being partly divided vertically by a web or partial partition 5.

Numeral 4 denotes a lifting bar or rack having ratchet teeth along one side to be engaged by a liftlng pawl, as usual in this class of devices.

In this jack the lifting pawl 6 is pivoted at 7 to the jack-operating handle 8 which is pivoted at 80, said pivot terminating at the plane of the open side of the box. The head of said pawl has a transversely extending notched lug 50 forming a bearing for a spring.

Pivoted tov the pawl 10 one end of which is adapted to engage and to release the lifting rack teeth, andthe other end of which carries a post 11, said holding pawl and post 11 being on different sides of the pivot. Pressing the lifting pawl toward the lifting rack or bar Specification of Letters Patent.

Application filed April 1, 1911.

standard at 9 is a holding Patented Mar. 19, 1912.

Serial No. 618.398.

arm 13. As shown, and as preferred, said two spring arms are formed of'one wire, roiled and loosely held at an intermediate point around the hub or collar bya clamping washer or directly by the head on the pivot 9.

A. suitably shaped pawl-controlling revorsing lever 120, is pivoted on the web in box One arm curves upward and toward the handleside of the jack, and to it, near its end, is pivotally connected a link 15 having an elongated slot which loosely engages the post ll. In the adjustment shown in full lines in Fig. 1 said link leaves the holding pawl free to be moved into engagement with the lifting bar teeth by the spring ill. The other end of lever 120 is curved upward and backward, extending under the lug 50, but in this adjustment out of the range thereof.

16 is a spring pressing upward on a shoulder of lever 11.20. Said spring is merely slipped into place, being normally held therein by the removable side plate 3.

Loosely mounted in front of the web on the extended end of the pivot 80, is a swinging dog '18 which when in raising adjustmentholds up the adjacent end of the lever 120 and the link 15 so that when the jack handle is moved down a full stroke, the lifting pawl will raisethe lifting bar a little more than the length of one tooth, and the holding pawl will be forced under a tooth to hold the lifting bar during reverse movement of the handle and lifting pawl to cause the latter to engage the next lower tooth, and so on repeatedly.

After the lifting bar is raised and 'is being held by the pawl 10, in order to lower it, the dog 11.8 is swung to dotted position (Fig. 1) and spring 16 tilts the lever 120, pullin down the link 15 against the post 11, and carrying the opposite end of the lever into the path of the lifting pawl lug. In this condition of parts the rack is held by pawl 10, the jack handle falling freely part way down, and the lifting pawl moves under a The standard 1 1s cast with an opening 25 in one side into which projects an integral lug 26. The lifting bar has at its foot a shelf or lug 27 and a longitudinal groove. After the bar is placed in the standard said lug 26 is bent inward so as to come into the path of the shelf27 to arrest the rack. The opening 25 beingcomparatively large a suitable tool can he used therein for reversely bending. the lug when it is required to remove the lifting bar for any reason.

The number of parts of'the jack operating mechanism is small, and the parts are such that they can be readily put in place and removed. Both the spring 16 and the dog 18 are preferably only secured by the overlying cover plate. The holding pawl, lifting pawl and the handle, are all back of the web 5 (although the two pawls have extensions to the front of the web), and the controlling lever, its spring, and thedog 18, are in front of said web. So also is the spring acting on the pawls.

For strength and for ease of removal, the handle pivot and also the holding pawl pivot, not only pass through the web 5 but also through the back side of the box.

The impro-vement'is not limited to parts of the exact form and. arrangement shown as they can be varied within the scope of the invention. Thus, the torsion spring having arms 12* and 13, instead of being clamped directly against the web 5, may be held on a collar or hub cast on the web and through which the pin 9 passes, and which permits the spring to turn to a certain extent on the collar while the pawls are -moved to their difi'erent positions. The link between the holding pawl and the pivoted pawl-control ling lever may be directly pivoted to the former and connected to the latter by pin and elongated slot, this being a mere reversal of the construction shown and described;

What I claim and desire to secure by Letters Patent is,--

1. In a jack, the combination of a standard comprising a box, a lifting rack, a lift ing pawl, an operating handle on which the lifting pawl is pivoted, a holding pawl pivoted intermediate its ends to said standard, a pawl-controlling lever pivoted to the standard, a yielding connection between said pawl-controlling lever and said holding pawl, said connection with the holding pawl being on the other side of the pivot from the rack-engaging end, and a locking and unlocking dog for said lever also pivoted to said standard.

2. In a jack, the combinationvof a standard comprising a box, a lifting rack, a lift ing pawl, an operating handle to which the lifting pawl is pivoted, a holding pawl pivoted to said standard, a pawl-controlling lever pivoted to the standard, and a locking and unlocking dog for said lever also pivoted to said standard, said dog being supported on an extension of the handle pivot.

3. A jack comprising a standard having a box, a partial partition dividing said box,

a lifting rack, a lifting pawl, a holding pawl, and a handle, all mounted behind said partition; a pawl-controlling lever, a spring acting thereon, said lifting pawl having an-extension beyond the partition into coiiperative relation with the pawlcontrolling lever, and said holding pawl being operatively connected at 1ts end remote from said rack to the pawlcontrolling lever, and a lever adjusting dog in front of said partition.

4:. In a jack, the combination with alifting rack, a lifting pawl, and a holding pawl, of a single spring held by the holding pawl pivot at an intermediate point, the tension of said spring being applied by both of said pawls.

5. In a jack, the combination with a lift- .ing rack, a lifting pawl, and a holding pawl centrally pivoted, a post' thereon op posite the rack-engaging end, of a pawlcontrollingdever, a link connected to said pawl-controlling-lever and having an elongated opening through which said post projects, whereby in one adjustment of the link the post is free to move in the opening and in another adjustment it is not.

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

GLEN- RUSSELL BOOTH. Vitnesses VIOLET M. BOOTH, WM. DILDINE.

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