US922856A - Lifting-jack. - Google Patents

Description

A. M. COLT.

LIPTING JACK.

APPLICATION FILED MAY 6, 1908.

Patented May 25, 1909.

Mfzwaees:

A. M. COLT.

LIFTING JAUK.

APPLICATION FILED MAY 6, 1908.

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BATAVIA, NEW YORK.

LIFTING-JAGK.

No. eeaese.

Specification of Letters Patent.

Patented May 25, 1909.

Application filed May 6, 1908. Serial No. 431,281.

To all whom it may concern:

Be it known that l, ALVA M. (Your, a citizen of the United States, residing at Batavia, in the count of Genesee and State of New York, have invented a new and useful Imrovement in Lifting-Jacks, of which the folowing is a specification.

This invention relates to lifting jacks and more particularly to lever-operated jacks suitable for lifting automobiles or wagons.

The objects of the invention are to produce a powerful lifting jack of compact, simple and inexpensive construction in which the weight can be either raised or lowered step b. step by like motions of the hand lever; a o to roduce a jack composed of few arts of simple and stron construction Whic are separable and can e readily assembled for use and taken apart to enable them to be more readily stored away or transported; also to construct the jack so that the lifting dogs can be'arranged very close to the lifting ar to give a powerful leverage with a short hand lever; and also to rovide a novel spring device for controllin t e action of the hfting do s to enable the li ting bar to be moved at wil in either direction by the same motion of the lever.

In the accompanying drawings, consisting of two sheets; Fi ure 1 is an elevation, partly in section, of a li ting jack embodying the invention. Fig. 2 is a detached perspective view of one of the lifting dogs. Fig. 3 is a fragmentary transverse sectional elevation of the jack. Fig. 4' is a detail sectional elevation of the turn button for controlling the di-- rection of movement of the lifting bar. Fig. 5 is a fra mentary sectional elevation of the parts of the jack separated. Fig. 6 is a fragmentary sectional elevation of the jack, in line 6-6, Fig. 3 showing the same adjusted for raising the lifting bar. Fi 7 is a similar view thereof, showing the jar; adjusted for lowering the lifting bar. Fig. 8 is a horizontal section in line 8-8, Fig. 6.

Like letters of reference refer to like parts in the several figures. V

A re resents the standard or frame of the the toothed lifting bar, C the hand jack,

ever, and D D the dogs for operating the lifting bar.

The standard may be of any suitable construction, but preferably consists, as shown, of a hollow column or pipe (I. screwed at opposite ends into a base a, and a frame or castin a having lever openings a at opposite si es thereof.

The lifting bar B is movable vertically in and is guided by the standard, and is provided at itsupper end with a suitable lifting head 5 and at op osite sides with ribs formed with ratchet teet b.

The lever C extends into the standard frame a through one of the side 0 enings thereof and is provided at opposite si es with projecting trunnions c which rest in open seats 0, Figs. 3 and 5, provided therefor in the inner sides of the op osite portions of the frame at Open-ended horizontal grooves c in the opposite sides of the frame lead from the openings 0. of the frame to said trunnion seats to guide the trunnions into the seats when placing the lever in the standard. A'

hole 0 Fig. 3, extends vertically through the inner end of the lever through which the lifting bar passes.

The lifting dogs D D are pivoted in the hole 0 of the lever at opposite sides of the lifting bar so that their u per ends or noses can swing into and out o engagement with the teeth of the lifting bar. The dogs preferably have integral pivot trunnions or studs (1 at opposite sides which rest in open seats d in the ever at opposite sides of the hole 0 thereof, and the dogs are preferably hollow or of U-shape in cross section, as shown in Fig. 2, so that the sides of the dogs can straddle the toothed ribs of the lifting bar. This construction of the dos enables them to be located closer to the ifting bar than solid dogs of the same size and strength could be, and this close arrangement of the dogs gives an increased leverage. The distribution of the weight of the metal in the dogs is such that their upper ends tend to swing away from the lifting bar and rest against the u er edges of the end walls of the hole 0 in t e i causing the noses of the dogs to engage the ratchet teeth of the lifting bar for raising the same. This s ring preferably consists of a resilient wire ent to the shape shown in Figs. 6 and 7. It is secured centrally by a screw 6, or other means, to one side of the standard frame a above the dogs and has two legs or side portions which have spring coils and extend downwardly from the securing screw and have outwardly bent lower portions with inbent ends 6 The legs of the spring normally tend. to close toward each other, as shown in Fig; 6, and when in this position their inbent ends bear on lugs cm stated. The turn button consists of a short the spring and s shaft pas'singthrough a hole in the side of the standard frame and having a thumb piece or handle at its outer end for turning it and an elongated head f at its inner end located between the legs of the spring and having notched ends adapted to engage the legs of read the same when turned from the vertica position shown in Fig. 6 to the horizontal position shown in Fig. 7. The turn button preferabl has a lug f, Fig. 4,.entering a segmenta recess f 2 in the standard frame and adapted to strikethe ends of said recess to limit the rotary movement of the turn button. The legs of the spring E bearingagainst the head f hold the turn button in either position to which itis turned.

The spring E could be of somewhat different shape than shown in the drawings and still operate in the same manner, and instead of the two legs or portions of s ring being made in one integral piece, it Wlll be manifest that the two portions could be separate pieces suitably secured in place, and the term s ring is employed in this specifica tion wit .thls broader meaning. Any other suitable device could-be used in lace of the turn button for spreading the egs of the spring.

The operation of the jack is as follows: If it is deslred-to raise the lifting bar the turn button F is turned to the vertical position shown in Fig. 6, which allows the legs of the e noses of the dogs into operative engage ment with the teeth of the lifting barf Then by oscillating the hand'lever the dogs are a ternately raised and lowered. When the lever is forced downwardly the dog D ascends and en aging under one of the ratchet teeth raises t e lifting bar while the other dog D spring to close toward eachv otherand press I t slldes downwardly over the inclined face of one of the teeth and is caused to sna under the tooth by the spring. When the ever is ralsed the dog D ascends and lifts the bar whlle thedog D descends and takes a new hold, 'so that the lifting bar and the weight thereon are raised with each movement of the lever. To lower the weight the turn button is turned to the horizontal position shownin Fig. 7, which spreads the le s of the spring E, lifting its ends ofi of the ugs on the dogs. Then when the lever 1s depressed the dog D engaging the length of one tooth under one of the. teeth descends and lowers the lifting bar and the other dog D ascends, being held by its weight out of engagement with the teeth of the bar until the upper edge of the end wall of the hole 0 in t e lever strikes the dog and presses it inwardly be neath one of the teeth, when, by the con tinued downward movement of the lever, the ascending dog takes the-load ofi of the descending dog, which then swings by gravlty clear of the teeth. U on raising the lever the dog D descends and lowers the lifting bar and the other dog D rises to take a new hold on another tooth in the same manner as the other dog D when the lever was lowered, the dogs thus acting alternately to lower the lifting rod and its weight the length of one tooth with alternate ments of the lever. 11 the spring E is s read, as explained, to cause the lowering of the lifting bar, its ends are held in a osition to strike the lugs on the dogs as the proach the upper limit of their movement, and throw the dogs into engagement. with the ratchet teeth. Thus the spring alone would serve to actuate the dogs to either raise or lowerthe lifting bar, but the end walls of the hole a of the lever arranged as described for positively actuating the dogs for lowering the lifti g bar are desirable and are referably employed.

The spring E is secured in the standard and is not connected with the pawls but is simply adapted to bear against them, and when the legs of the spring are spread apart by turning the turn button F to the horizontal position, the lever with the dogs in place thereon can be readily placed in position in and removed from the standard, the lifting bar B of course being first "taken out of the standard. The do s are removably seated in the lever and can e removed from the same when the lever is taken out of the standard.

I claim as my invention 1. In a lifting ack or the like, the combination of a standard, a lifting bar movable therein provided with o osltely disposed ratchet teeth, a lever f dicrumed on said pp and down moveogs apstandard, dogs carried by said lever at o I posite sides of its fulcrum for engaging sald ratchet teeth, a s ring secured to said standard, means for ad iustlng said spring to cause 1t to engage and press said dogs into engage- -ment with said ratchet teeth at the end of the'down strokes of said dogs for raising said mg bar or to leave the dogs free to swin out o engagement with said teeth at the end of the down strokes of the dogs for lowerin said hftlng bar, and parts which engage said dogs and move them into engagement with said ratchet teeth at the end of their up strokes when they are left free by said spring, substantially as set forth.

2 In a lifting Jack or the like, the combinatlon of a stan ard, a lifting bar movable therein providedwith 0 ositely disposed ratchet teeth, a lever crumed on said standard, dogs carriedby said lever at opposite sides of its fulcrum for engaging sald ratchet teeth, a s ring secured to said standard, and means or adjusting said spring to one position in which it presses said dogs a ainst said ratchet teeth for raising said li ting bar or to another position in which it leaves said dogsfree to swing away from said ratchetteeth at theend of the down strokes of the dogs and remain out of engagement with said teeth during a part of the up strokes of said dogs and then moves said dogs into enga ement with said ratchet teethat the end 0 their up strokes for lowering said lifting bar, substantially as set forth.

3. In a lifting jack or the like, the combination of a standard, a lifting bar movable therein and provided with oppositely disposed ratchet teeth, a lever fulcrumed on said standard, oppositely arranged dogs ivoted on said lever at op osite sides 0 its fulcrum for engaging sa1 ratchet teeth, a spring secured to said standard and having opposite legs for pressing said dogs into engagement with sald ratchet teeth for raising said liftin bar, means for spreading said legs of the sprlng to leave said dogs free to swing by gravity away from said ratchet teeth at the end of the down strokes of the dogs for lowering said lifting bar, and parts on said lever for moving sald dogs into enga ement.

with said ratchet teeth at the end of t eir up strokes when they are thus freed from said spring, substantially as set forth. I

4. In a lifting jack or the like, the combination of a standard, a lifting bar movable in said standard and having oppositely arranged ratchet teeth, a lever fulcrumed on said standard, dogs pivoted on said lever at opposite sides of its fulcrum to cooperate with said ratchet teeth, a spring secured on said standard above the fulcrum end of said lever and having opposite legs which, when left free to spring toward each other, press said dogs into engagement with said ratchet teeth for raising said lifting bar, a turn button on said standard between said spring legs and adapted to be turned to spread said spring legs apart to leave said dogs free to swing away from said ratchet teeth for'lowering said lifting bar, and means for movin said dogs to engage said teeth at the end 0 their up strokes when said dogs are free from said spring, substantially as set forth.

Witness my hand, this 24th day of April,

ALVA M. COLT. Witnesses:

ALFRETTA BUCHHOLTZ,

NEWELL K. Conn.

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