US1231623A - Lifting-jack. - Google Patents

Description

G. LANE.

LIFTING JACK.

APPLICATlON FILED NOV- 29,19;- l ,%31 623, Patented July 3, 1917.

Illllllllllll UMTE @TATS OFFTQEQ GEORGE LANE, OF POUGHKEEPSIE, NEW YORK, ASSIGNOR TO LANE BROS. C0,, OF POU'GHKEEPSIE, NEW YORK LIFTING-J'ACK.

To all whom it may concern:

Be it known that I, GEORGE LANE, a citizen of the United States, and a resident of Poughkeepsie, New York, have invented certain new and useful Improvements in Lifting-Jacks, of which the following is a specification.

My present invention relates to improvements in lifting jacks adapted more espe cially for use in connection with motor vehicles, though by no means limited to such use, and is designed as an improvement or modification of the jack which forms the subject of Letters Patent of the United States, No. 1,122,235, dated December 22nd, 1914, and also on that disclosed in an application filed by me November 17, 1916, No. 131,911.

The invention has among its objects the following to wit:

To avoid the necessity of using any coil springs acting on the pawls, and to materially reduce the number of springs required;

To provide a. very simple and efficient manner of forcing the pawls alternately forward during the step by step lowering of the lifting bar;

To provide a convenient means under the control of the operator for permitting the lifting bar to drop freely to its lowermost position;

To have the parts completely housed and protected so as to prevent injury when the jack is subjected to rough usage, as while being carried in the tool boX of an automobile; and

To generally improve the construction with a view to increased simplicity, durability and economy of manufacture.

With these objects in view the invention includes the novel features of construction and arrangement and combination of parts hereinafter described and particularly defined by the appended claims.

Several embodiments of my invention are illustrated in the accompanying drawings, in which,

Figure 1 is a side elevation of a jack embodying my invention with one side plate of the casing removed to show the operating mechanism, the parts being in lifting posi tion.

Specification of Letters Patent.

Patented P111113 3, 1917.

Serial No. 134,159.

Fig. 2 is a view similar to Big. 1 with the parts in position to lower the lifting bar step by step.

Fig. 8 is a sectional detail view.

Referring by reference characters to these drawings the numeral 1 designates the base, 2 the standard and 8 the lifting bar which may be constructed and arranged as described in my aforesaid patent, the lifting bar having on one face the ratchet teeth 3 and at its upper end a suitable head 3*.

The holding pawl 4. is pivotallv supported in a suitable manner upon the standard while the lifting pawl 5 is similarly mounted upon the inner end of the lifting or actuating lever 6.

The actuating lever 6 is provided with a socket 6 to detachably receive a hand lever 7 and said actuating lever is pivoted at 10 between the side plates 8 suitably-secured to the standard and forming a housing or casing for the actuating lever, pawls and controlling mechanism hereinafter de scribed.

The actuating lever supports a carrier for pawl controlling or operating means, which carrier is movable longitudinally of the actuating lever or in a direction toward and from the lifting bar and pawls.

I prefer to make this carrier in the shape of a yoke or U-shaped member 11, one arm 11 of which is pivotally supported by the actuating lever, while the other arm 11" extends transversely through an open space 6* in the actuating lever so as to be capable of being swung in said space toward and away from the lifting bar.

To the portion of the carrier bar 11 which projects beyond the face of the actuating lever, is pivotally connected a pair of bell crank levers 12 and 12 of fiat sheet metal, one of which. as 12, lies in close proximity to the side of the actuating or socket lever, and the other, 12 lies close to the lever 12. This bell crank'12 has an upwardly deflected or extended arm a, which is connected by a link 13to the lifting pawl 5, while the other bell crank 12 has a downwardly deflected arm Z) similarly connected by link 14 with the holding pawl 4. Said bell cranks have rearwardly extended arms a and Z) respectively designed to cooperate with a stud or projection 15 on one of the side plates 8 to effect the step by step lowering of the lifting bar in the manner hereinafter described.

A spring 16 has its intermediate portion coiled around the extremity of the bar 11 and its ends extended in opposite directions and connected respectively to the arms a and b of the bell crank levers. The tension of this spring is such that it tends to press the pawls toward and into engagement with the teeth of the ratchet bar, and, conversely, the reaction tends to force the arm 11 of the carrier member away from the ratchet bar to the limit of movement allowed by the opening in the actuating lever through which said carrier projects or by the controller carried by the handle bar.

The handle bar 7 is designed to be locked in position in the socket of the actuating lever by a spring pawl 7. The handle bar carries at one side a longitudinally movable rod 17 suitably held in position, as for instance, by having its front end doubled backward upon itself, and guided iuan elongated opening in the end of the handle bar, as disclosed in my aforesaid application. The rear end. of the rod is connected to a suitable actuating device, preferably in the form of a winged button, indicated at 18, also disclosed more in detail in said application.

The forward. end of the rod passes into a groove in the side wall of the actuating lever in line with the carrier or yoke bar 1 1 andwhen the handle bar is in position in the actuating lever socket and the rod 17 has been pressed forward by the proper rotation of the button, the carrier is pushed forward against tension of the spring 16 and both links 13 and 11 are placed under increased compression, and the bell cranks are moved forwardly and. spread apart sutliciently to cause their arms a and Z) to be always out of contact with the stud 15. Movement of the actuating lever up and down then causes the pawls to alternately engage the teeth of and lift the ratchet bar, the idle pawl riding, over the teeth of. the bar as the working pawl is effecting the lifting holding action. The position of the parts during the lifting action is shown in Fig.1. j

The lifting bar having been raised to the proper height and,it beingdesired to lower the load, the button 18 is turned to retract the rod' 17, (as indicated by the dotted lines Fig. 3,) This allows the carrier to move backward or outward under the tension of the spring, which causes the arms d, b,

which beforewere widely separated, to close down upon opposite sides of thestuchor rojection 15 into close proximity thereto. gupposing, for example, that at the completion of the lifting action the jack has come to rest. with the hand lever depressed and the upper pawl retaining the load (as shown in full lines, Fig. 2) and the rod 17 to have been moved backward to allow the spring to force the bell cranks backwardly as above stated, the contact of the stud 15 with the arm 6 holds the same, rocked against the tension of the spring, in position to draw the holding pawl out of engagement with the teeth of the ratchet bar. Raising of the handle bar in the direction of the arrow carries the carrier 11, which is the pivot of the bell crank levers, upwardly which tends to move arm 6 away from the contact pin, allowing the bell crank lever to be rocked on its pivot by the spring tomove the holding pawl toward the ratchet bar. At the same time the lifting pawl, and with it the ratchet bar, is being lowered. The parts are so proportioned that the holding pawl does not move into engagement with the ratchet bar until it has cleared the next upper tooth, when it drops into the recess between the teeth of the ratchet bar and receives the load. By this time the carrier pivot l1 has moved upwardly sufficiently far to cause the arm a to contact with the stud or projection 15 which rocks the bell crank lever 12, so as to throw the arm a thereof backward against the tension of the spring, thus drawing the lifting dog out of engagement with the ratchet bar. Downward movement of the handle now shifts carrier pivot 11 soas to allow' the lifting, pawl to be again pressed toward the ratchet bar, but in moving for ward it clears the tooth which it had previously engaged and comes into operative relation tothe next upper teeth ready to re ceive the same andlower the lifting bar an other step on the next upward movement of the actuating lever. Thus in the lowering action the pawls are alternately drawn away from the ratchet bar and forced into engagement therewith by spring action. The.

of the distance, as, for instance, when a motor car axle has been,lowered sufliciently to allow the tire to contact with the ground.

In order toprovide means for effecting this dropping of the lifting bar which shall be under the control of the operator, 1, provide the arm a with an extension or thumb piece a projecting beyond the back edge of the side plate 8. To drop the ratchet bar it is only necessary to grasp the socket lever with the thumb bearing against this thumb,l-.5

lowermost position.

piece a and move the socket lever downwardly. The result of this is that the socket or actuating lever in its downward movement draws the holding pawl backwardly clear of the ratchet teeth in the manner hereinbefore described while the pressure of the thumb on the extension a rocks the bell crank lever connected to the lifting pawl and draws the latter backwardly out of engagement with the ratchet teeth. Both pawls thus being disengaged from the ratchet teeth, the lifting bar drops freely to its This provides an extremely simple and effective method for the quick dropping of the lifting bar which is accomplished by a predetermined and voluntary act on the part of the operator, and hence there is no danger of an unexpected drop with the possibility of the pinching of the fingers, as I have found sometimes occurs in constructions where an automatic drop is provided when the jack is used by people unfamiliar therewith.

As the bell crank extension a lies immediately against the side of the actuating lever and is protected by the overhanging side plate, it is not likely to be injured while the jack is being carried in the tool box of a motor vehicle. All other working. parts are housed and fully protected by the plates. While I have shown in the drawings one side plate removed to show the operating parts, it will be understood that in actual practice the side plates are made to completely cover the working mechanism hereinbefore described.

What I claim is 1. A jack comprising a standard, a lifting bar, an actuating lever, a lifting pawl and a holding pawl cooperating with said lifting bar, a single spring tending constantly from the actuating to press both said pawls toward the lifting bar, and means for alternately drawing said pawls away from the ratchet bar against the spring tension.

2. A jack comprising a standard, a lifting bar, an actuating lever, a lifting pawl and a holding pawl cooperating with said lifting bar, a pair of levers pivotally supported lever and connected respectively to said lifting and holding pawls, spring means tending normally to rock said levers to press the pawls toward the lifting bar, and means for alternately rocking said levers against the spring tension as the actuating lever is operated.

3. A jack comprising a standard, a lifting bar, an actuating lever, a lifting pawl and a holding pawl cooperating with said lifting bar, a pair of levers pivotally supported from the actuating lever and connected respectively to said lifting and holding pawls, spring means tending normally to rock said levers to press the pawls toward the lifting bar, and contact means supported from the standard for alternately rocking said levers against the spring tension.

4. A jack comprising a standard, an actuating lever, a lifting bar, a lifting pawl and a holding carrier supported by said actuating lever to be movable lengthwise thereof to either of two determined positions, a pair of levers pivotally supported from said carrier and connected respectively to said pawls, a spring reacting between said levers and tending to force said pawls yieldingly toward the ratchet bar, manually controlled means for determining the position of said carrier, and contact means supported from the standard adapted to alternately rock said levers against the spring tension when the carrier is in its rearmost position.

5. A jack comprising a standard, an actuating lever, a lifting bar, lifting and holding pawls cooperating therewith, a pair of levers having a common fulcrum supported from said actuating lever to be movable lengthwise thereof, links connecting said levers to said pawls, a spring connected to said fulcrum and exerting tension on said levers to press the pawls toward the lifting bar, contact means supported from the stand ard for alternately rocking said levers when the fulcrum is in its outermost position, and means for pressing the fulcrum toward the lifting bar aganst the tension of the spring.

6. A jack comprising a standard, a lifting bar, an actuating lever, a lifting pawl and a holding pawl cooperating with said lifting bar, a single spring tending constantly to press both said pawls toward the lifting bar, means for automatically alternately drawing said pawls away from the ratchet bar against the spring tension and manually operated means for drawing one of said pawls backward against the spring tension.

7. A jack comprising a standard, a lifting bar, an actuating lever, a lifting pawl and a holding pawl cooperating with said lifting bar, a pair of levers pivotally supported from the actuating lever and connected respectively to said lifting and holding pawls, spring means tending normally to rock said levers to press the pawls toward the lifting bar, and contact means supported from the standard for alternately rocking said levers against the spring tension, and manually controlled means for rocking one of said levers.

8. A jack comprising a standard, an ac tuating -ever. a lifting bar, lifting and holding pawls cooperating therewith, a pair of bell crank levers pivoted to a common fulcrum movably supported lengthwise of said actuating lever, a spring reacting between said levers and fulcrum, said levers having substantially vertically extending arms connected to said pawls, and having also rearpawl cooperating therewith, a

wardly extended arms, a contact device supported from the standard and adapted to cooperate with said rearwardly extended arms when the fulcrum is in its r'earmost position, and means for shifting said fulcrum forwardly against the tension of its spring.

9. A jack comprising a standard, an actuating lever, a lifting bar, lifting and holding pawls cooperating therewith, a pair of bell crank levers pivoted to a common fulcrum movabl-y supported lengtlnvise of said actuating lever, a spring reacting between said levers and fulcrum, said levers having suh-' stantially vertically extending arms con nected to said pawls, and having also rearwa'rdly extended arms, a contact device supported from the standard and adapted to cooperate with said rearwardly extended arms When the fulcrum is in its rearmost position, and means for shifting said fulcrum forwardly against the tension of its spring, and an extension on one of said arms to enable the same to be manually operated against the spring tension.

10. A jack comprising a standard, a lifting bar, an actuating lever, a lifting pawl and a holding pawl cooperating with said lifting bar, a pair of hell crank levers pivota-lly supported from the-actuating lever and connected respectively to said lifting and holding pawls, and a fixed abutment on the jack frame for alternately contacting with said bell crank levers as the actuating lever is operated.

In testimony whereof, I aflix my signature.

GEORGE LANE.

Copies: of. this atent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G.

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