US1571132A - Lifting jack - Google Patents

Description

Jan. 26 1926.

J. R. MARCHESSEAULT LIFTING JACK Filed Feb. 16, 1923 4 Sheets-Sheet 1 Jan. 26 1926.

- J. MARCHESSEAULT LIFTING JACK Filed Feb. 16 1923 4 Sheets-Sheet 2.

Jan. 26 1926.

J. R. MARCHESSEAULT LIFTING JACK Filed Feb. 16, 1923 4 Sheets-Shut 5 Jan. 26 1926.

J. R. MARCHESSEAULT L'IFTING JACK 1923 4 Sheets-Sheet 4 1 Filed Feb. 16

m 77IZIZENZOR. I

ORN Y I w w v v 4. 2 MW Ha A Patented Jan. 26, 1926.

warren sit OS PH t ,a a v M CA mam Stem a CORPORATION OF CONNECTICUTQ I} i raraur QFE-LQE.

MARQlaTESfiEAUL-T, or nn nenron'r, oonnncrrour, ass enpn To r111; MPANY, or nnrnenronr, CONNECTICUT, A

LIIE TIN 'G- JACK.

Application filed February 16, 1923. Seria1 No. 619,355.

To all whom it may concern Be it known that Ldosurn R. MARorInssnAUL'r, a citizen of the UnitedStates, residing at Bridgeport,Connecticut, have invented certain new and useful Improvements in Lifting Jacks, ofwhich I declare the following to be a full, clearfand exact description.

My invention relates to improvements in lifting jacks and has to do, more particularly, with jacks of the general type used in connection with automobiles.

The chief object of my invention is to provide a, lifting jack of improved and simplified construction which is strong and durable in construction but comparatively light and such that it may be manufactured ata comparatively low cost.

A further object of. my invention is to provide a lifting jack having pawl mechanism so arranged that the pawls, pawl-actuating spring and actuating lever may be assembled apart from the jack casing and I mounted in place in the latter by a simple and convenient assembling operation, thus making the construction very cheap and easy to manufacture.

A further object of my invention is to provide a lifting jack having an improved and simplified reversing 'mechanism by which the parts are changed, from lowering to raisingvposition and vice versa.

A further object of my invention is to provide an improved jack construction having a single pawl-actuating spring and means'whereby the change from raising to lowering position is effected by pressure applied to certain portions of the spring.

Further'objects, and" objects relating to details and economies of'constructionand. operat on, Wlll definitely appear from the detailed; description to follow. In one instance, I accomplish the objects of my in vention by the devices and means set forth in the following specification. My invention is clearly defined and pointed out in the appended claims. A structure constituting a preferred embodiment of my invention is illustrated in the accompanying drawings, forming a part of this specification, inwhich? Fig. 1 isa view ofthe ja k in Side elevatlon.

Fig. 5 is a detail sectional view on the line 55 of Fig. 2. i

Fig. 6 is a view of the spring.

Fig. 7 is a plan and side elevation view of the reversing lever, and

pawl-actuating 8. is a view of the jack, similar to Fig. 2, but showing the parts in lowering position.

In the drawings, the same reference numerals refer to the same parts throughout the severalviews and the sectional view is taken looking in the direction of the arrows at the ends of the section line.

It, has been common practice, heretofore, to construct lifting jacks consisting of a casing in which a rack is slidably mounted, the rack having a head which engages beneath the part to be lifted. The rack is actuated for raising or lowering the load, due to the coaction therewith of a lifting pawl carried by the actuating lever and a holding pawl mounted 011 a fixed pivot. Various spring devices have been suggested which yieldingly force the pawls into engagement with the rack during the raising movement and, when the mechanism is set for lowering,'interinittently throw the pawls into and out of engagement with the rack. My invention consists in mounting both the pawls and the spring which actuates them upon the act-uating lever so that the pawls, spring and leveirmay be assembled together andthen mounted in position inthe jack casing. My invention further consists in a single spring, preferably mounted on the holding pawl pivot, and acting 'on both the lifting and holding pawls, the action of on the pawls being changed, for reversing, by pressure applied to certain portions of the spring upthe spring. This spring is preferably coiled stud or projecting portion on the holding pawl. This spring has a spring and lever action, when'the mechanism is set forlowering, so that the movement of the lifting pawl tends to swing the holding pawl into and out of engagement with the rack but, when pressure is applied to the spring by the reversing lever the two arms of the spring act independently to throw the pawls into engagement with the rack.

Referring to the numbered parts of the drawing, in which I have shown a lifting jack constituting one embodiment of my invention, the jack casing, 10, is fastened to the base, 11, and houses the pawls and the parts associated therewith. The rack, 12, is channelshapcd and has the teeth, 14, struck out from the base of the channel. The head, 1.3, is fastened to the upper end of the rack. The inner end of the actuating lever, 15, is forked and terminates in the spaced parallel plates, 16, between which the lifting and holding pawls work. The actuating lever, 15, has socket to receive a handle constituting an extension of the lever. The lever, 15, is fulcrumed on the pivot pin, 17, which extends between and is supported by the side members of the casing, 10. The pivot pin, 17, also constitutes the fulcrum for the holding pawl, 23, which extends upwardly therefrom so that its free end is in proximity to the teeth, 14, of the rack, 12. The butt end of the pawl, 23, is positioned between the side plates, 16, of the actuating lever.

The pin, 18, carried by the inner ends of the side plates, 16, of actuating lever, 15, is the pivot on which the lifting pawl, 19, is mounted. Inasmuch as the pin, 18, is carried by the lever, 15, the pawl, 19, is raised and lowered as the handle of the lever is lowered. and raised. The butt end of the pawl, 19, is positioned between the side plates, 16, of the lever and its free end eX- tends into proximity with the rack teeth, 14, below the holding pawl, 23. One side of the pawl, 19, has a thickened portion or shoulder, 20, adjacent its pivot, and a transverse rib, 21, the rib being spaced from the shoulder so as to form the groove or slot, 22, between them. This slot, 22, receives one arm of the pawl-actuating spring.

The pawl-actuating spring is coiled around a boss, 27, formed on the holding pawl, 23, around the pivot, 17. One arm, 28, of this spring extends upwardly radially from the coiled portion, 26, and is lodged in the groove Or slot, 22, of the lifting pawl, sliding therein as the pawl is raised and lowcred. The opposite arm, 25, of the spring extends radially upward from the coiled portion, 26, and embraces a stud, 24, projecting laterallyfrom the side of the hold ing pawl near the free end thereof. The arm, 25, extends laterally, at 29, over the stud, 24, toward the free end of arm, 28, then downwardly, at 30, toward the pivot, 17, and is then bent back upon itself forming the free end portion, 31, which terminates adjacent the stud, 24. The portions, 30 and 31, of the spring lie on and are adapted to engage opposite sides of the stud, 24.

A reversing lever, 33, is pivotally mounted on one of the side members of casing, 10, by means of a screw, 32, which is screwed into the lev r, 33, and passes through a hole in the casing, 10. A spring, 35, compressed between the head of the screw, 32, and the casing, 10, forces the lever into frictional engagement with the inner surface of the casing, so that the lever will tend to remain in the position to which it has been adjusted. The lever, 33, has a laterally extending finger, 34, near its pivot, which is so located as to engage the portion, 25, of the spring.

In assembling the jack, the pawl, 19, may be pivoted in the actuating lever, 15, the holding pawl, 23, inserted in position in the actuating lever to receive the pivot, 17, and the spring mounted on the pawls with the coiled portion, 26, journaled on the boss, 27, arm, 28, in the groove or slot, 22, and the other arm embracing the stud, 24. The parts thus assembled may be inserted in the casing as a unit and secured in place by the simple operation of inserting the pivot pin, 17. It will be observed that this makes it very easy and convenient to assemble this jack and thus reduces the cost of manufaeture.

This jack construction operates in the following manner. hen it is to be used for raising a load, the head, 13, is placed beneath the load to be lifted and the reversing lever, 33, is moved to the position shown in Figs. 2 and In this position, the finger, 34, on the reversing lever engages the portion, 25, of the spring and exerts a pressure thereon, forcing it toward the rack. This causes the whole spring to rotate somewhat around the boss, 27, this movement being ieldingly resisted by the engagement of the arm, 28, with the shoulder, 20, and the portion, 31, with the stud, 24. hen pressure is applied thus by the reversing lever, 33, to the portion, 25, of the spring, the arms, 23 and 3 act on shoulder, 20, and stud, 24, respectively, and yieldingly force the lifting and holding pawls into engagement with the rack, 12. lVhen the parts are in the position shown in Fig. 2, the holding pawl, 23, engages one of the teeth, 14, of the rack and supports the load. If the handle fitting in the socket of the actuating lever, 15, is now raised, the pawl, 19, descends, riding over the inclined surface of one of the teeth, 14, and being forced by the pressure of the spring arm, 28, into engagement with the ower eeef a l etlithe handle is or e l 1 s't e h-E Wl; ssce dscar v ls with t the sa k 2, n the h lding paw ri s Ov t i cl ned's r ace of a tooth, ll, and is o -ced by spring arm, 31, into engagement vith the lower face ofsaid tooth. ,By repeated novements of the ac tuatinglevergthe rack, .12, is rnisedpne tooth at im hen it isdesi ed to w r th load, thereversinglever, 33, tulinod tothe position shown in Fig. '8, ,in which the finger, 4, d enot exert Pressures t e p rt ms e-sp ing- In ig.- he pa tare shown in position f lowering-and theiload is ca ed y h l t-i s pa l, 9, wh h is in engagement \vitlro-ne .o-f thejteeth, 3114, of the ra k- AS the handle of he actuating W 1 s ra sed, 5-11 6 ra l, .9, d scends and the rack descends with it until ftheholdr I s p wl, 2 engages he ooth, mm

above it. lVhe-n this occurs, the descent of the rack is interrupted and the loadshifts from the lifting pawl to the holding pawl, 23. hen this takes place, the pawl, 19, has moved (to such position with respect to pivot, 17, that the arm, 28, -O;f'il1 (3 spring engaging the rib, 2d, swings the pawl, 19', away from the ,rack. The handle is :now loweredcausing the pawl, 19 to ascend and, as the pawl ascends, its movement with respect to the pivot, 17, causes the arm, 28, of the spring to press on shouldsli, 2.0, and force he p w to ngagement w t the ne highest tooth of the rack. Continued upward mox ement o pawl, 19, lifts the rack slightly, thus Sh ting the load from the holding pawl, hen this takes place, the lifting pawl is insuch position that shoulder, 20,exerts a pressure on arm, 28, of the spring which is effective, when the load is ren'ioved from pawl, 23, to swing the spring around the boss, 27, causing portion, 30 thereof to bear on stud, 24k, and move pan "1,23, away from the rack so that the latter can be lowered one tooth, In this manner, the load maybe lowered step by step, one tooth at a time.

I am aware that the lifting jack illustrated herein as an embodiment of my invention may hechanged' or varied considerably with out departing from the spirit of my invention, and, therefore, I claim my invention broadly, as indicated by the appended claims.

Having thus -.desorib.edmy invention, what I claim as new and useful and desire to secure by Letters Patent is 1. A lifting jack comprising a casing, a rack slidably mounted therein, an actuating lever pivoted on said casing, a lifting pawl carriedby said lever and engaging said rack, a holding pawl pivoted on said. casing and engagin said rack, and a single spring n ounte on the holding pawl pivot only and ngaging b t of said auls, said pr ng 3. A lifting jack comprising a casing, a

rack slidably mounted therein, an actuating lever pivoted on said casing, a lifting pawl carried by said lever and engaging the rack, a holding pawl pivoted on the casing and engaging said raolga single spring journaled on a common pivot with said holding pawl and-engaging both of said pawls, and a re versing member movable to a position in which it engages andexerts pressure on said spring.

i, A lifting jack comprising a casing, a rack slidably mounted therein, an actuating lever pivoted on said casing, a lifting pawl carried by said lever and engaging the rack, a holding pawl pivoted on the casing and engaging said rack, a single spring journaled on a common pivot with said holding pawl and engaging both of sait pawls, and a reversing lever pivoted on said casing and movable to a position in which it engages and exerts pressure on said spring.

5. A lifting jack comprising a casing, a rack slidably mounted therein, lever pivoted on said casing,a lifting pawl carried by said lever and engaging the rack, a holding pawl pivoted on the actuating lever pivot and engaging said rack, a single spring journaled around said pivot and engaging both of said paw'ls, and a reversing membermovable to a position in which it engages and' exerts pressure on said spring.

6. A lifting jack comprising a casing, a rack slidabl-y mounted therein, an actuating lever pivoted on said casing, a lifting pawl carried by said lever and engaging said rack, a holding pawl pivoted on said casing and engaging said rack, and a single spring journaled on an axis coincident with that of the holding pawl and having one arm engaging the lifting pawl and another arm engaging opposite sides of a portion of the holding paw-l near the free end thereof.

7. A lifting jack comprising a casing, a rack slidably mounted therein, an actuating lever pivoted on said casing, a lifting pawl carried by said lever and engaging said rack, a holding pawl pivoted on the casing and engaging said rack, and a single spring journaled on an axis coincident with that of the holding pawl and having one arm positioned in a slot in the lifting pawl and he other a m eng g n p i d s of an actuating stud on the holding pawl near the free end thereof.

8. A lifting jack comprising a casing. a rack slidably mounted therein, an actuating lever pivoted on said casing, a lifting pawl carried by said lever and engaging said rack, a holding pawl pivoted on the casing and engaging said rack, and a spring coiled around the holding pawl pivot only and having one arm engaging the lifting pawl and another arm lying alongside of the holding pawl and engaging opposite sides of a stud projecting laterally from the holding pawl.

9. A lifting jack comprising a casing, a rack slidably mounted therein, an actuating lever pivoted on said casing, a lifting pawl carried by said lever and engaging said rack. a holding pawl pivoted on said casing and engaging the rack, said pawl having a stud projecting from one side thereof, and a wire spring having a coil intermediate its ends journaled around the holding pawl pivot, one arm extending radially from said coil into engagement with the lifting pawl. and a second arm extending radially from said coil toward the free end of said holding pawl, thence extending toward the free end of the first-mentioned arm above said stud. thence extending radially toward said coil between said stud and the lifting pawl, and thence bent back upon itself to form a free end extending on the opposite side of said stud from the lifting pawl.

10. A lifting jack comprising a casing, a rack slidably mounted therein, an actuating lever pivoted on said casing. a lifting pawl carried by said lever and engaging said rack. a holding pawl pivoted on said casing and engaging said rack, a single spring journaled on an axis coincident with that of the holding pawl and having one arm engaging the lifting pawl and another arm embracing a portion of the holding pawl near the free end thereof. and a reversing member movable into engagement with said spring near the free end of the holding pawl.

11. A lifting jack comprising a casing, a rack slidably mounted therein. an actuating lever pivoted on said casing, a'lifting pawl carried by said lever and engaging said rack. a holding pawl pivoted on said casing and engaging the rack, a spring coiled around the holding pawl pivot and having one arm engaging the lifting pawl and another arm lying alongside of the holding pawl and embracing a stud projecting laterally therefrom. and a reversing lever pivoted on the casing and movable to a position in which it exerts pressure on said spring adjacent the portion embracing said stud.

12. A lifting jack comprising a casing, a raclr slidably mounted therein, an actuating lever pivoted on said casing, a lifting pawl carried by said lever and engaging said rack. a holding pawl pivoted on said casing-and engaging said rack, saidpawl having a stud projecting from one side thereof a wire spring having a coil intermediate its ends journaled around the holding pawl pivot, one arm extending radially from said coil into engagement with the lifting pawl, and a second arm extending radially from said coil toward the free end of said holding pawl, thence extending toward the free end of said first-mentioned arm above said stud, thence extending radially toward said coil between said stud and the lifting pawl, and thence bent back upon itself to form a free end extending on the opposite side of said stud from the lifting pawl, and a reversing member movable into engagement with the radially extending portion of said spring adjacent its junction with the portion extending above said stud.

13. A lifting jack comprising a casing, a rack slidably mounted therein, an actuating lever pivoted on said casing, a lifting pawl carried by said lever and engaging said rack, a holding pawl pivoted on the actuating lever pivot and engaging said rack, and a single spring journaled on an axis coincident with that of said pivot and having one arm engaging the lifting pawl and an other arm embracing a portion of the holding pawl near the free end thereof.

14:. A lifting jack comprising a casing, a rack slidably mounted therein, an actuating lever pivoted on said casing, a lifting pawl carried by said lever and engaging said rack, a holding pawl pivoted on the actuating lever pivot and engaging said rack, and a single spring journaled on an axis coincident with that of said pivot and having one arm positioned in a slot in the lifting pawl and the other arm embracing a stud on the holding pawl near the free end thereof.

15. A lifting jack comprising a casing, a rack slidably mounted therein, an actuating lever pivoted on said casing, a lifting pawl carried by said lever and engaging said rack, a holding pawl pivoted on the actuating lever pivot and engaging said rack, and a spring coiled around said pivot and having one arm engaging the lifting pawl and another arm lying alongside of the holding pawl and embracing a stud projecting laterally from the holding pawl.

16. A lifting jack comprising a casing, a rack slidably mounted therein, an actuat ing lever pivoted on said casing, a lifting pawl carried by said lever and engaging said rack. a holding pawl pivoted on the actuating lever pivot and engaging the rack, said pawl having a stud projecting from one side thereof, and a wire spring having a coil intermediate its ends iournaled around said pivot, one arm extending radially from said. coil into engagement with the lifting pawl, and a second arm extending radially from said coil toward the free end of the holding pawl, thence extending toward the free end of the first-mentioned arm above said stud, thence extending radially toward said coil between said stud and the lifting pawl, and thence bent back upon itself to form a free end extending on the opposite side of said stud from the lifting pawl.

17. A lifting jack comprising a casing, 21 rack slidably mounted therein, an actuating lever pivoted on said casing, a lifting pawl carried by said lever and engaging said rack. a holding pawl pivoted on the actuating lever pivot and engaging said rack, a spring coiled around said pivot and having one arm engaging the lifting pawl and another arm lying alongside of the holding pawl and embracing a stud projecting laterally from the holding pawl, and a reversing lever piv oted on the casing and movable to a posi tion in which it exerts pressure on said spring adjacent the portion embracing said stud.

18. A lifting jack comprising a casing, a 'aek slidably mounted therein, an actuating lever pivoted on said casing, a lifting pawl pivotall; mounted on said lever and engaging said rack, said pawl having a slot in one side face thereof, a holding pawl en aging said rack and pivoted on an axis coincident with that of said lever, said pawl having a stud projecting from one. side thereof, and a spring journaled around the pivot of said holding pawl and having one arm positioned in the slot of the lifting pawl and another embracing the stud on the holding pawl.

19. A lifting jack comprising a casing, a rack slidably mounted therein, an actuating lever pivot-ed on the casing, a lifting pawl pivotally mounted on said actuating lever, a holding pawl having a hub portion around its pivotal axis, and a spring coiled around the hub portion of said holding pawl only and acting on both said pawls, said pawls, spring, and actuating lever being capable of assembly outside of the casing and subsequent mounting in the casing as a unit.

In testimony whereof, I aflix my signature.

JOSEPH R. MARCHESSEAULT.

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