US1520937A

US1520937A - Lifting jack

Info

Publication number: US1520937A
Application number: US701861A
Authority: US
Inventors: Herbert L Dickey
Original assignee: Individual
Current assignee: Individual
Priority date: 1924-03-25
Filing date: 1924-03-25
Publication date: 1924-12-30
Anticipated expiration: 1941-12-30

Description

Dec, 30, 1924. E W

y H. L. DICKEY LIFT ING JACK Filed March 25, 1924 5 sheets-sheet L 1,520,937 H. L. DICKEY v LIFTING JACK Filed March 25, -1924 3 Sheets-Sheet 2 H. L. DICKEY LIFTING JACK Dec. 30, 1924- 1,520,937

Filed March 25. 1924 3 Sheets-Sheet 5 Patented Dec. 3o, 1924.

UETED HERBERT L. DICKEY, O'F DETROIT, MICHIGAN.

LIFTING JACK.

Application filed March 25, i924. Serial No. 701,861.`

To all whom t may cow/067%.' v

Be it known that I, HERBERT L. DICKEY, a citizen of the United States, residing at Detroit, in the county of Wayne, and State of Michigan, have invented certain new and useful Improvements in Lifting Jacks, of which the following is a specification.

This invention relates to a lifting jack. It is especially designed to fulfill the requirements of the trade for a jack that may be low in price but yet sturdy enough to do the required work. It is common practice to furnish all cars at the factory with a set of 'tools including a jack. Since these jacks must necessarily cost very little, it is my purpose to construct one in which the number of parts has been decreased and the cost of the jack in proportion.v I form the severa-l parts of the jack from stampings or mallea'ble castings and provide an easy assembly l of the several parts so as to decrease the labor cost. y

Another object of the invention is to provide yieldable means forcing the actuating dogs into engagement with the rack bar and an additional spring member for forcing one of the actuating dogs out of engagement with the rack bar, the parts being so arranged that the second mentioned means may be placed in an inoperative position when the rack bar is raised and when the rack bar is lowered this spring means functions so as to throw the lock dog out of engagement but adapted to be momentarily released to allow the locking dog to again engage the rack bar.

Fig. 1 is an elevational view of my improved form of lifting jack.

Fig. 2 is a bottom plan view lof the base support. l

Fig. 3 is a detail showing the means for locking the're'verse lever taken substantially on the line 3-3 of Fig. 1.

Fig. 4 is a detail taken on the line 4-4 of Fig. 2, showing how the housing and base lsupport are secured together.

Fig. 5 is a detail showing the working vparts of the jack in elevation when using the jack to raise the rack bar.

Fig. 6 "is `asimilar View showing a differentposition of the Yactuating parts.

Fig. '7 is a similar view showing the arrangements lof 'parts when the rack bar is .being lowered.

Fig. Sis a view similar to Fig. 7 showie-io or rig. i.

ing another position of the jack operating parts. y Y

Figi) is a transverse section on the line 9 9 of Fig. 5. I

Fig. 10 is a transverse section on the line Figs. 11 and 12 are transverse sections similar to Fig. 10 showing modified forms of the rack bar that may be used.

Fig 13 is a sectional detail taken on the line 13-18 of Fig. 7, showing the offset cam for throwing out the lifting dog.

' Fig. 1li is a detail in perspective of the reverse lever. p

15 is a section on the line 15-15 of Fig. 14.

Fig. 16 is a. detail in perspective ofthe spring tending to force the dogs into engagement with thelock bar. j

Fig. 17 is a detail in perspective "of the safety-pin type of spring for throwingout guidedvertically within the housing and is provided with the ratchet teeth d. As shown in Figs. 10 to 12 inclusive, these teeth are formed by cutting or casting grooves in the face of the rack bar which are concave transversely thereto.' In Figs. 11 and 12, I show a modified form of rack bar in which the rack bar is an I-beam section (Fig. 12) and Fig. 11 is an I-'beam section formed by securing two channels back to back. In using an `I-beam section such vas shown in these modified forms, it would be impossible to cut the groove straight across `as the .cut would break through` the flanges of the jI- beam and reduce the strength of the same, and the groove concave transversely of the rack bar does `not weaken the rack bar. By using'this form of rack bar I find that the costis materially reduced 'as is also the weight'without lessening the strength ofth jack.

A stud e pivotally supports the .operan ing lever fin the housing (see Figsv to 8 inclusive) and the forward end of the lever pvotally supports the 'lifting dog h on `the pin or stud g carried thereby. The locking dog` 'i is pivotally supported on the stud c which is the fulcrurn of the lever. Ubviously, the locking dog has merely a rocking motion while the lifting dog has a recipro-r ating motion well as a rocking motion. .5i spring j is coiled about the stud c and the stud g which pivotally support the locking dog and the lifting dog respectively, the free ends of said spring bearing against the backs of the dogs for forcing the said dogs into engagement with the teeth d of the rack bar.

ln order to raise the racli bar c referring more particularly to VFigs. and (i, the operating lever f is roclfed thus imparting a reciprocating motion to the lifting dog. frs the le' is rocled from a position shown in Fig. 5 to that shown in Fig. 6, the lifting dog it is pulled d i wnwardly until it reaches a position so that the spring 'y' may force the dog into the nent lower notch of the rack During this movement the locking dog` 1 is in engagement with the rack bar and thusV prevents the saine from falling while the lifting dog is out of eng 'ement therewith. As the lever' /f is now rocking downwardly it will carry the lifting dog upwardly and thus raise the rack har the distance of one tooth. TWhile the rack bar is so raised, the locking dog merely rides out of the notch and falls into the next lower notch, whereupon the operation is repeated.

rIhe lowering of the rack bar presents a more complicated problem and in order to obtain the proper actuation of the lifting 'dog and the locking dog it requires a different actuation of the parts. lijivotalljyY supported on the housing on the pin '1,01 is a manually operated reverse lever which is provided with an offset cani mi, which when in the posit-ion shown in Figsk 5 and 6 when the rack bar is being raised, is in a noninterfering position with the lifting dog. But in F l and 8, the reverse lever is lowered or has been rotated in a clockwise direction so as to bring the cam m carried thereby into an interfering position with the lifting dog /i. ln 13, it will he seen how this can'rfif'iis oliset with respect to the plane of the reverse lever so as to lie in the Y plane of the lifting dog.

The edge of the lifting dog is cut away as at n for a purpose later to he described.

jx safety-pin type of spring designated 0 is coiled about the stud e one end of which bears down upon the stud which supports the lifting dog, and the other end bearing against the inside edge of the locking dog. The reverse lever is provided with a struck out tongue j? (Figs. le and l5) which is adapted to engage the end of the spring 0 and to hold the saine from engagement with the locking dog while the reverse lever is. inY a position as shown in Figs. 5 and 6. How

ever, when the reverse lever is lowered the struck out tongue j) releases the spring 0 and allows the same to bear against the lool;- ing dog. Vilhile the operating lever f is in he position as shown in lFig. 7, the lifting dog in a raised position which thus tends to wind up the spring o so that it will exert a force on the locking dog su'liicient to throw the saine out'of engagement with the racit bar. This spring is so constructed that when it is wound up as shown in Fig. 7, it will overcome the tendency of the spring j tending' to force the locking bar into engagement with the rack bar, and thereby `hold/tlm locking bar out of engagement with the rack har. As the operating lever is rocked to lower the lifting dog it will unwind the spring o and thus decrease the force ofv the spring bearing against the locking bar to hold, the same out of engagenient with the rack bar. As the force of the spring o is decreased the spring will overcome the spring 0 and force the locking dog into engagement with the rack bar. As the lifting dog is lowered the cani in strikes the lifting dog and throws the same out of engagement with the locking bar (see Fig. 8). The timing of the movement ofthe locking dog and tl e lifting dog is such that as the liftinoi dog lowered the 'rack will move downwardly therewith and as the locking dog released from the pressure of spring o it will engage trie next higher tooth of the rack har previous to the time when the lifting dog is forced completely out of engagenient with the rack bar. As the operating! lever is again rocked so as to raise the liftinf' dog, the cam m holds the dog out of engrgr-H with the rack bar until it has raised a sutlicient distance and then the spring ,7' forces the saine into engagement with the rack bar the said lifting dog engaging the next higher notch oi' the rack bar, whereupon when the operating lever reaches its full stroke the locking dog is forced out of engagement with the rack bar because of the fact that the spring 0 has been wound up and possesses suliicient force to overcome the force of the spring This cycle of operation will be repeated and the jack is lowered notch by notch until the racl bar has been lowered the required distance. Y

The housing blank is cut in such a manner that the saine may he folded in at the front so as to close the housing at the front with the exception of where the operating lever projects through the housing. rihe housing is formed with a slot q through which the reverse lever is adapted to project. The upper end of the slot is enlarged as at fr forming the shoulder s on which the reverse lever 7u rests when it is pushed up. ji coil spring t bears against the reverse lever and tends to force the saine downwardly but the shoulder s is inclined at such an angle that this 4downward force tends to push the reverse lever' yto the left (see Fig. 3) and prevent the same `from falling into slot g. To use the jack so as to lo-wer the raclr bar, it is merely necessary to push the lever 7c from off the shoulder s' whereupon the spring t will force the same down the slot into the position shown in Figs. 7 and 8 whereby the ack may be used to lower the rack bar.

Referring to Fig. 9, it will be noticed that the handle or operating lever f is split at the end and flattened as at u. The studs e. and g which pivotally support the locking dog z' and the lifting dog it are carried by the flattened end of the lever f. The outer` end of the lever is tubular in cross section and adapted to vreceive an loperating bar or lever o so that one may obtain the necessary leverage to operate the jack. About the pin w, which pivotally supports the reverse lever 7c, is a spacing sleeve ai which is of such a diameter' that it will just touch the rack bar and thus guides the rack bar as the saine is reciprocated vertically.

IVhat I claim is: p Y

l. In a lifting jack, the combination of a housing, a rack bar guided vertically therein,

a lever pivoted in the housing, a lifting dog pivotally supported by the lever for engag- 'ing the teeth of the rack, a locking dog piv otally supported for engaging the teeth of the rack, and a differential stressing spring means engaging the locking dog and controlled by the lifting of the lifting dog to cause the spring stress tending to release the locking dog from said rack bar to overcome the spring stress tending to engage the locking dog with said rack bar and controlled by the descent of the lifting dog to cause the spring stress tending to engage the locking dog with said rack bar to overcome the force of the spring stress tending to release the locking dog from said rack bar.

2. In a lifting jack, the combination of a housing, a rack guided vertically therein, a pivoted lever supported by the housing, a locking dog, a lifting dog carried by the pivoted lever, the two dogs arranged to engage the teeth of the rack, a spring engaging both dogs for yieldably forcing the same into engagement with the rack, and a spring for engaging the locking dog alone and e1'- erting a counterforce on said locking dog, whereby as the lifting dog is raised by the lever the locking dog is forced out of engagement with the teeth of the rack, and whereby the lowering of the lifting dog reduces the force of the spring tending to release the locking dog to allow the spring for forcing the same into engagement to overcome such counterforce.

3. In a lifting jack, the combination of a housing, a rack guided vertically therein, a pivoted lever supported by the housing, a

locking dog, a .lifting dog carried by ythe pivoted lever, the two dogs arranged to'engage the teeth of the rack, yielding means operating on the dogs tending to force the same .into engagement with the rack, anda safety-pin type of spring, one end engaging the locking dog and the otherendfengaging the lifting dog whereby the raising'of the said lifting dog tends to wind up the spring soV that the same will exert va force on the locking dog to disengage the saine from the rack and the lowering of said lifting -dog unwinds the spring to allow lthe yielding means to Vforce the locking dog into engagement with the rack. f

4. Ina lifting jack, the'combination of a housing, `a rack guided vertically therein, a pivoted lever supported by thefhousing, a locking dog, a lifting dog carried by the pivoted lever, the two dogs arranged -to engage the teeth `of the rack, yielding lmeans operated `on the dogs for forcing `the same into engagement with the rack, and a safetypin type of spring having one end engaging the locking dog andthe other; end engaging the stud which pivotally supports the lifting dog, whereby the raising of said lifting dog windsup the spring vto force the locking dog out of engagement with'the rack while the lowering of the lifting dog disengages the lifting dog from the teeth of the rack bar and unwinds the spring so that the yieldable means may force the locking dog into engagement with the rack bar before the said lifting dog is disengaged from the teeth of said rack bar.

5. In a lifting jack, the combination of a housing, av rack guided vertically therein, an operating lever pivotally supported by the housing, a lifting dog pivotally supported by the pivoted lever, a locking dog supported at the fulcrum point of said lever, the two dogs arranged to engage the teeth of the rack, yieldable means for forcing the dogs into engagement with the rack, and a safety-pin type of spring anchored to the fulcrum of the operating lever and locking dog, and having one end engaging the lifting dog and the other end engaging the locking dog, whereby the raising of the lifting dog winds upl the spring to throw the locking dog out of engagement with the rack and the lowering of the lifting dog unwinds the spring to allow the yieldable means to force the locking dog into engagement with the rack.

6. In a lifting liaclr, the combination of a housing, a rack guided vertically therein, a pivoted lever supported by the housing, a locking dog, a lifting dog carried by the pivoted lever, the two dogs arranged to engage the teeth of the rack, yielding means operating on the dogs to force the saine into engagement with the rack, a reverse lever supported by the housing and provided with a. cam which maybe thrown into an interfering or non-interfering position with the lifting dog7 and a spring anchored to the housing and having one end engaging the lifting dog and the other end the locking dog whereby the lowering of the lever winds up the spring and exerts a force on the locking dog to disengage the same from the rack and the lowering of the lifting dog causes the same `to strike the cam carried by the reve-rse lever tov throw the lifting dog out of engagement with the rack and unwinds the spring to allow the yielding means to Lforce the locking dog into engagement with the rack.

7. In a lifting jack, the-combination of a housing, a rack guided vertically therein, a pivoted lever supported by the housing, a locking dog, a lifting dog carried by the pivoted lever, theV two dogs arranged to engage the teeth of the rack, a reverse lever provided with a cam offset in the plane of the lifting dog and adaptedto be moved into an interfering position with said lifting dog, and yielding means operating on the dogs whereby when the lifting dog is forced downwardly by the lever the yielding means serve to throw the locking dog into engagement with the teeth and the cam carried by the reverse lever strikes the lifting dog to throw the same out of engagement with the rack.

8. ln a lifting jack, the combination of a rack bar having ratchet teeth with intervening grooves concave transversely of the rack bar, dogs engaging said ratchet teeth, and means for actuating said dogs to raise or lower said rack bar.

9. n a lifting jack, the combination of a rack bar formed of an I-beam section and having ratchet teeth with intervening grooves concave transversely of the rack bar, dogs engaging said ratchet teeth and means for actuating said dogs to raise or lower the rack bar.

10. In a lifting jack, the combination of a rack bar, formed of a pair of channel members secured together bach to back to form an -section, said rack bar having ratchet teeth with intervening grooves concave transversely of the rack bar to forni ratchet teeth, dogs engaging said ratchet teeth, and means for actuating said dogs to raise or lower said rack bar.

In testimony whereof l affix my signature HERBERT L. DICKEY.