US1329098A - Jack - Google Patents

Description

P. W. SCHIEMAN.

JACK.'

APPLICATION FILED MAY 24. 1911.

Patented J an. 27, 1920i.

4 SHEETS`SHEET I.

lll IIlII||lIIIIIIIIIIIIIIHIIIIIIHIH Illll P. wscHlEMAN.

JACK.

APPLICATION FILED MAYZ4| 19|?.

Patented Jan. 27,1920.

4 SHEETS-SHEET 2.

' 'Illll P. W. SCHIEMAN.

JACK.

APPLICATION FILED MAY 24. 1917.

Patented Jan. 27, 1920.

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P. W. SCHIEMAN.

JACK.

APPLICATION FILED MAI/24, IsII.

Patented J an. 27, 1920.

4 SHEETS-SHEET 4.

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@o i IIIvIl. a 9 J 2 IMI' I 5 23 I a f u/ a a was ,/I; IIIII UNITED- STATES FATENT OFFICE.

PAUL W. SCHIEMAN, OF EOCKTLLE GENTER, NE'W YGRK, ASSIGNQR TO THE A. DEW'E'IS4 "V A CORPOBATIGN OF NEW YORK.

COMPANY, OF NEW YORK., N.

JACK.

Application led May 2, 1317.

To all whom t may concern.'

Be it lrnown that l, PAUL lN. SCHIEMAN, a citizen of the United States, and a resident of Rockville Center, in the county of Nassau and State of New York, have invented certain new and useful Improvements in Jacks, of which the following is a specification.

rEhe invention relates to a new manually operative jack adapted for use in connection with motor vehicles, as well as being capable of efficient use in lifting or jacking-up other vehicles and apparatus.

The jack of my invention comprises a general casi-ng, which will preferably be inade of stamped metal, a vertically movable lifting-bar mounted in said casing, and a pivoted manually operative handle for effecting the movement of said lifting-bar, together with certain more particularly novel features residing in a new construction and arrangement of operative parts connected and cooperating with the lifting pawls or dogs which alternately engage said lifting-bar during the o1 eration of said handle, means for reversing the action of said pawls or dogs so to secure the descent the lifting-bar when it is desired to lov.

the load, means for conveniently releasing both pawls or dogs from the lifting-bar when it may be desired to allow the said bar to drop to its lower position without the necessity of operating said handle, and an auxiliary low step or shoe which may be enliployed for engaging the load when the same cannot conveniently be received by the main head on the upper end of the liftingar, said auxiliary low step or shoe hav ing a novel construction and mounting adapting it for various adjustments and to successfully sustain the load which may be imposed upon it.

rIhe invention will loe fully understood from the detailed description her after presented, reference being had to the accompanying drawings, in which:

Figure l is a vertical section through a jack constructed in accordance with and embodying the invention, the parts of the mechanism of the jacl: being shown in the position the)7 occupy when the operating lever handle is in itsA per position and the vertically moi-fable lifting-bar has been starred in upward motion? the section be ing on the dotted line ll of Fig. 2;

Specification of Letters Patent.

Patented Jan. 27, 1920.

serial No. 170,589.

Fig. 2 is a front elevation, partly in vertical section, of the same, the front of the main casing having been removed so as to expose the interior mechanism;

Fig. 3 is a view corresponding with Fig. l, partly broken away, showing the relan tive relation of the various parts ofl the mechanism after the operating lever handle has been turned downwardly to nearly its lower position in the process of elevating the lifting-bar;

Fig. 4l is a corresponding view showing the relative relation of the parts of the mechanism after the operating lever handle has reached its lower position and the upper pawl or dog has passed into engagement with the liiting-bar;v

Fig. 5 is a perspective view of the jack, with the lever handle partly broken away and in its lower position and the mechanism set for effecting, from said handle,'the

lowering of the lifting-bar, and the lateral lifting' member or low step or shoe being shown at the side of the jack instead of at the rear thereof, as in Fig. l;

Fig. G .is a view corresponding with Fig. l, partly broken away, showing the relative relation of the parts of the mechanism when the same are set for the lowering of the lifting-bar, the operating lever handle being` shown somewhat above its lower position;

Fig. 7 is a corresponding view of a portion of the same illustrating the relative relation of the parts of the mechanism when the operating handle has reached a lowei` position than that illustrated in Fig. 6;

Fig. S is vertical section through the auxiliary lateral lifting member and is presented to illustrate the manner of vertically adjusting the step or shoe of the same;

Fig. 9 is a sectional view corresponding with Fig. l, but illustratingthe two dogs as ne;` ly tripped from the lifting bar;

Fig. l0 is a transverse section through the jack, taken on the dott-ed line 10-10 of Fig. l, and

Figs. 11 and l2 are detached perspective views of two parts of the operative mechanism of the jack identified hereinafter.

, In the drawings, 15 designates the general exterior casing of the jack whose two sides and back portion are preferably in one integral stamping of sheet metal and whose front portion comprises a lower section 16 and an upper removable section 17, more clearly shown 1n F 1g. 5, which 1s fastened to the body of the general casing by screws 18 and by being interposed at its upper end behind a lug 19 formed of the general casing and extending frontwardly of the lift` ing-bar 20. The general casing composed of the parts is secured at their lower edges to a base composed of. a stamped metal exterior portion 21 and a filling 22, which may be of wood. The lower edges of the casing are flanged under adjacent portions of the base member 21, as shown in Figs. 1, 6 and 9. The base portion of the jack may be variously modified, but I illustrate a base which is capable of being readily constructed and comprising a stamped up metal part or cap 21 and a wood filling 22. The back portion of the general casing 15 is made narrow, as at 23 (Fig. 10), to serve as a guide for the lifting-bar 20. At convenient points the opposite sides of the guide 23 are provided with inwardly extending pins 24 entering vertical grooves 25 in the opposite sides of the lifting-bar 20 so as to aid in guiding said bar and retaining the same within the narrowed back portion of the casing 15. At the lower end of the liftingbar 20 and secured thereto are laterally extending pins 26 which are within the aforesaid grooves 2,5 and directly below the aforesaid pins 24, and during the upward movement of the lifting bar the pins 26 finally reach the pins 24, which are rigid with the casing 15 and at such time the pins 24 by their engagement with the pins 26 arrest the bar 20 on its upward movement, defining the limit of the upward movement of said bar. At the limit of its downward movement, the lifting bar 20 may extend into a recess 27 formed in the general base of the device.

The lifting-bar 20 is a strong metal bar which is rectangular in cross-section and has on its front face a series of rack teeth 28 adapted to the lower and upper pawls or dogs 29, 30, which alternately coperate with the' rack teeth 28 during the operation of the jack to either raise or lower the lifting-bar 20, although as hereinafter described, I have provided means by which both of said pawls may be released from the bar 20, so that said bar may descend by gravity. Upon the upper end of the bar 2O is provided a concave foot 31 adapted to receive the axle or other part of the object to be lifted and formed with a depending head or socket portion 32 which closely fits upon the upper end of the bar 20 and may be detachably connected therewith by means of an ordinary set-screw 33. The head or socket 32 is, at one side, formed with laterally extending arms 34 between which is pivotally mounted a supplemental bar 35 which extends downwardly along the general casing 15 and at its lower end may swing' against the same, so as to obtain support therefrom, as shown in Fig. 1. The socket in the head 32 is rectangular in crosssection and may be applied upon the bar 2O stood on reference to Fig. 5. rlhe bar 35 is of T-shape in horizontal crss-section, thereby forming a web portion which is hold by the pivot 36 between the arms 34 of the head or socket 32 and a head portion 37 affording flanges extending laterally from said web portion and which portion 37 is formed in its outer face with a series of recesses 38. Upon the bar 35 is placed a vertically adjustable step or foot 39 comprising a horizontal member 40, a downwardly extending member 41 engaging the outer face of the bar 35, and inner and laterally extending members 42 which embrace the side edges of the head 37 and extend inwardly along the inner faces of the iianges afforded by said head 37. The vertical portion 41 of the step or foot 39 is formed with a stud 43 adapted to enter any'of the recessses or sockets 38 formed in the outer face of the bar 35. The step or foot 39 is vertically adjustable on the bar 35, and in F ig. 8 l illustrate said step or foot in a tilted position releasing its stud 43 from one of the recessses or sockets 38 so that said step or foot may be slid either upwardly or downwardly on the bar 35 and have its stud 43 engaged with some other one of the sockets or recesses 38 for the purpose of varying the initial position of said step or foot 39. rlhe jack is used under varying conditions and sometimes the foot or shoe 31 may answer the requirements, but at other times the side supplemental step or foot 39 will become necessary, and in the construction presented' the initial height from the ground of said step or foot 39 may be varied to suit the conditions to be met with. `When the step or foot 39 is tilted upwardly, as shown in Fig. 8, it may be slid upwardly or downwardly on the head 37 of the bar 35 and have its stud 43 introduced in any of the sockets or recesses 38 to secure the proper vertical adjustment of said step, said step when reaching the de# sircd recess or socket 38 being turned into its horizontal position so as to project the stud 43 into such recess or socket 38.

Among the novel features of the jack are the hinged bar 35 adapted to engage, at its lower port-ion. the general casing 15 and the adjustable step or foot 39 mounted` on said bar. lt will be observed that by reason of the pivoting of the bar 35 a weight imposed on the step or feo-t 39 will exert its forcel against the general casing 15 as well as en lili lid)

the pin or pivot 36, and that in consequence thereof such weight will not be likely to bend or break the lifting bar Q0 or do other damage to the jack, and this is a result which l dee-m to be of' very great importan-ce` The. tact that the supplement-al har 85 and step or i'oot 89 may be disposed at the rear of the general casing l5 or at either side thereof, is also a matter ot' importance in affording proper conveniences to the user of the ack. A wneight imposed on the step or foot 39 is well supported, not only the engagement ot the stud 43 with one of the sockets or recesses 38, but also by the inner wall ot' the vertical member 4l engaging the outer tace of the head 37 of the bar 35 and the engagement of the flanges 42 at the inner end ot' said step or foot 39 with the inner faces of the vertical flanges allorded by said head 37. T he bar 85 is provided at opposite sides of its lower end with pins 44 which serve to prevent the step or toot 39 from slipping downwardly off from said barv The bar 35 is prevented from having an)Y swiveling action around the bar 20', since said bar 20 is rectangular' in cross-section and the socket in the head 82 corresponds .in shape with and tits upon said bar 20'.

The pawl or dogl 80 is of substantial width, as shown in Fig. 2, and is pivot-ally mounted on a transverse pin 45, .vhich ex tends through the lower end of vsaid dog or pawl and through the opposite sides oit the general casing, and l may here state that the opposite sides of the general casing are made of double thickness, as shown in Fig.-

10, so as to afford. in a stamping, the requisite strength to withstand the uses to which the jack may be put. The double thickness of the sides of the general casing of the jack also afford substantial bearings for the pin 45 and the other pins or the like to be referred to hereinafter. rllhe upper end ci the pawl or dog 30 is adapted to the teeth of the lifting-bar 20, and adjacent to its up per end said dog or pawl 30 is formed on one side edge with an arm 46 which projects forwardly or toward the front of the jack and carries a small roller or pin 47 at the liront of a cam arm or plate 48 (Fig. 11) which is pivotally secured by a screw 49 to the upper front portion of a plate 50 (Fig. 12) which extends downwardly alongA the side ot the pawl or dog 29 and is mounted at its lower end upon the pivot pin 5l for the said dog or pawl 29. Vllhen the bar 20 is being lowered the upper cani shaped end oi the plate 48 is adapted to ride against the roller 47 and pull the engaging' end of the pawl 30 from the rack bar 2O at the time the dog 29 engages said bar. and thereafter the plate 48 will turn with the dog or pawl toward the bar Q0 when it is desired that said dog or pawl shall engage said bar 20 and support t ie load. During the upward movement of the lifting bar :20 the cam plate 48 has a nominal spring tension outwardly` or towai'd the front by the downwardly extending member 52 of a coiled spring 53 which is held upon a transverse pin 54 and has its downwardly extending member or arm confined behind a lip 55 formed on the. forward edge oi the plate 48. The. spring- 58 is ot' course stationary, and the dog or pawl 8O is stationary7 except for its pivotal movement, whereas the plate 48 has a vertical reciprocating` movement imparted to it during the operation ot the jack, and when the plate 48 is moifed upwardly, its upper cam shaped end is caused to ride against the roller 4T and pull the dog or pawl 80 outwardly from the lifting bar 20, this taking place moi'e especially during the descendingmovement ol? the lifting bar 2O and when the tension of the spring 58 has been materially increased by the means, hereinafter described, pro vided to so set the mechanism that the har 2O will descend when the lever handle is operated. The lower rearwardly projecting' portion of' the plate 48 is formed with a somewhat triangular]y-shaped slot or opening' 56, and within this opening` 56 projects a pin 57 which is rigid with the upper end of the lower pawl or dog 29. The opening 56 and pin 57 permit ot the plate 48 having a pivotal moven'ient with relation to the plate 50 and pawl or dog '29. The pin 51 upon w iich the lower dog or pawl 29 and plate 50 are secured does not extend through the sides of the casing ot the ack, but through the inner forked end of the handlesocket 58 which is pivotally mounted upon a pin 59 which extends through the sides ot the general casing ot thejack The inner end of the handle socket 58 serves as a crank for raising and lowering the dog or pawl 2,9 and parts connected therewith, and at its outer end said socket `is adapted to detachablhv receive a handle-bar 60, whereby the 'jack may be operated, said handle ba and socket constituting a lever handle for actuatingv the operative parts of the jack.

The part I have termed a handle-socket 58, is a hand actuating` lever and, preterably. instead oii'being made of considerable length said lever is Jformed with the usual socket. as shown, to receive the bar GO.

The dogs 29, 80 are normally pressed toward the lifting-bar "2O by means ot a spring` 60 which is mounted on a pin 6i (Fig. 2) and has a downwardly' extending end G2 pressing against the dog or pawl and au upwardly projecting,` end 68 pressing against the dog or pawl 30.

The lever handle is always rjiif'en its ordinary oscillatorv movement, whether it is desired that the lifting-'bar Q0 ol? the jack shall ascend or descend. In the position oi the parts shown in Figs. 1, 2, 8

and 4, the

oscillatory motion of the lever handle will, through the action of the pawls or dogs 29, 30 effect a step-by-step upward movement of the lifting bar 20 and load supported thereon. l however' provide means for so aliecting the relation of the inner mechanism of the jack that during the oscillatory motion of the lever handle, the lifting bar may, by a step-by-step movement, descend, and these means reside mainly in a thumbpiece or reverse setting lever 6-1 pivotall)` secured to the inner side wall of the general casing by means of a screw or the like 65 and having on its disk-shaped inner end a laterally projecting` pin 66 which normally is below an arm 67 of the spring 53 which acts against the plate 4:8. When the thumbpiece or lever 64 is turned upwardly or to the position shown in Figs. 1, 2, 3, l and 9, the pin 66 is carried downwardly from the arm 67 of the spring 53 and has no appreciable inluence on said arm or spring, except to almost wholly relieve the spring of its tension, and at this time the operation of the lever handle and pawls or dogs 29, 30 will be to elevate the lifting-bar 20. lNhen however the thumb piece or lever 64 is turned downwardly or to the position shown in Figs. 5, 6 and 7, the pin 66 will be carried upwardly against the arm 67 of the spring oand materially increase the tension or said spring so that its lower member will act with positive force against the cam plate 18, and under this condition of the mechanism the lifting-bar will descend by a stepby-step movement on the operation of the lever handle.

The means for effecting the drop or deA scent by gravity of the lifting bar 2O comprise a downwardly extending arm 68 which is integral with the body of the lifting pawl 29, and a trame 70 which is formed ot a bent metal rod having its lower end pivotally secured at 71 to a bracket 7:2 within the general casing 15. The frame 70 at its inner bent portion, which is of curved outline, rests against the arm 68 of the pawl 29, and the upper horizontal portion of the frame 7 0 projects through a hole 73 formed in the lower front portion 16 oi the casing 15 and within the casing is 'provided with a cross-pin 74, which prevents the upper end of the frame 70 from passing unduly out through the hole 73. rhe frame 70 has a limited oscillatory movement on the pivot 71, and during the ordinary use of the jack the arm 68 acts against the frame 70 so that the latter will oscillate, but at such time said irame 70 performs no duty. rlhe trame '70 is made use of only when the lifting bar 20 is to automatically drop, and at such time the frame 70 is caused to trip both of the pawls 29, 3G from said lifting bar. It is not necessary at any time that the lifting bar 2O be caused to drop, but it is thought to be a saving in time on some occasions to, after the bar 20 has been worked downwardly by means of the lever handle until the load has been taken off oi said bar, permit the bar to drop. When it may be desired that the bar 20, in my jack, drop automatically, l will withdraw the handle bar 60 from the socket 58 waen said handle bar and socket have been turnerL down to their lower position, and then poke or push the end of the bar 60 against the exposed eiid of the iframe 70, the result of which will be that the Yframe 70 will be forced inwardly against the arm 68 and effect the tilting outwardly ott' the pawls 29, 30 from the bar 20, leaving said bar unsupported and of course therefore permitting it to drop. `When the handle lever is turned to its lower position the arm 68 presses the frame 70 to an outei1 position or substantially that in which it is shown in Fig. 1, and at this time the lifting bar is supported on the pawl or dog 30. When, by means or the bar 60, the upper end et the Jrame 70 pusherL inwardly to carry the bend of said frame against the arm 68, both pawls 29, 3() are tilted outwardly and the bar 20 is allowed to drop. The presence et' the :trame 7 0 in position to cooperate witn the arm 68 and to be operated from a distance by the bar 60, is quite a convenience, because the exposed end of the frame 70 may be conveniently reached by the bar 60 from a distance and without any special' hunting for the exposed end of said frame 70, which will always be directly below the socket 58 for the bar 60. The tripping of the dogs from the lifting bar 20, when the lever handle is in its lower position, may be performed by pressing the frame 70 inwardly, whether the thumb piece or setting lever 64 is turned upwardly or downwardly, but this tripping oiE the pawls from the bar 2O is usually performed when the thumb piece or setting lever 64 is turned downwardly, because the dropping or' the bar 2O is not supposed to take place until said bar has been worked downwardly by the lever handle to such extent that the load has been relieved from its upper end. After the lifting bar has been allowed to drop, the settinO lever 64e should be turned upwardly so that the jack may be in condition for use for elevating purposes, and therefore after the frame 7 0 has been pushed inwardly, as yshown in F ig. 9, to trip both pawls from the lifting bar and said bar has been allo-wed to drop, the handle bar 60 may be used, at a reasonable distance from the jack, to turn the setting lever 64 to its upward position and then returned to the socket 58, thus leaving the jack in condition for further use it desired. ln Fig. 9 l illustrate a condition in which the bar 60 has been used to push the frame 70 inwardly for the purpose of permitting the bar 20 to drop and then employed for turning the setting lever G4 to its upward position, after which the handle bar 6() is shown as having been returned to the socket The operation of the jack will in many respects be understood. from the foregoing' description, but it is necessary that further explanation be made as to the mechanism more directly cooperating with the pawls or . dogs 29, 30.

lll/Then the lifting-bar is to be elevated, the setting-lever will be turned to its upper position, shown in liig. l, and this, as hereinbefore explained, has the effect of leaving only a nominal tension on the spring 53 insutlicient to modify the action of the spring 60 whose ends respectively press against the pawls or dogs 29, 30, the plate 4:8 thus being deprived, during the elevation of the bar 20, of any special utility. Upon the oscillatory motion of `the lever handle, under the conditions just stated, the pawl or dog 29 becomes the lifting pawl or dog, and the pawl 30 hy engaging the lifting bar, serves to support said bar and the load thereon when the pawl or dog 29 recedes from a tooth of the lifting bar and moves downwardly to engage the next lower tooth thereof. ln the position of the parts shown in Fig. l, the lever handle has been turned to its upper position and the dog 29 has entered a tooth of the lifting bar 2O and the dog 30 is ready to recede from the lifting bar on the down-stroke of the lever handle or move to the position shown in nig. Gn the down-stroke of the lever handle, the dog 29 elevates the lifting-bar 2() and the dog 30 remains in readiness to again engage said lifting-bar after the pawl v29 has performed its duty and is to be withdrawn from aid bar, the pawl or dog 30 then taking the position shown in Fig. l, as distinguished from that illustrated in Fig. 3. The dogs or pawls 29, 30 act alternately and are pressed against the bar 20 by the spring 60. The release of the dog` 30 from the rack-bar 2O takes place when the dog 29 has 4engaged a tooth of said 'bar and has been actuated to elevate the bar 20, the dog 30 du 1ing this period riding out from the tooth of said bar it engaged so as to snap into position below the neXt lower tooth thereof preparatory to supporting the load when the pawl 29 has completed its upward stroke. On the Lip-stroke of the lever-handle, the pawl 30 supports the har 2() and the load thereon and the pawl or dog 29 rides down the bar 2O to engage. another tooth thereof.

Then the lifting bar 2O is to be lowered, so as Vto lower the load imposed thereon, the setting-lever 64 will be turned to its lower position, shown in Figs. 5, 6 and 7, and this, as hereinbefore explained, has the etlect-ot` causing the pin 66 at the inner end of said lever tc move outwardly against the arm 67 of the spring 53 and thereby increase the Vension of said spring, through its arm 52, against the lip 55 of the plate 48. Upon the oscillatory motion of the lever-handle, under t ie conditions just stated, the pawls or dogs 29, 30 are alternately acted upon to effect the lowering of the lifting bar l2O by a step by step movement. Then the lever-handle is turned upwardly to lower the dog l29 and plate 48 (and therewith the loar 20), the plate t8 tilrns outwardly on the pivot L9 due to the shape of the upper portion of said plate and the tension of the spring-arm 52 against the same, and at .this time the dog or pawl 30, under the action of the springarm 63 is moved against the lifting-,bar20 so that it may support 4the same when the dog or pawl 29 is freed from said bar by .being turned outwardly therefrom on the pivot 5l, this turning-outwardly of the dog or pawl 29 being effected by the lowering on a downwardly and forwardly extending arcline of the pivot 5l and the upward and outward movement on an arc line of the rearwardly projecting lower portion of the plate -l-S, whereby the wall of its opening 56 is caused to act against the pin 57, which is rigid with the pawl or dog 29, to draw said dog or pawl n29 forwardly from the bar 20 in opposition to any fo ce the spring-arm 62 may exert. The joint action of the plate t8 and lever-handle near the end of the upward movement of said handle, has the effeet, before the dog 39 is ready to leave the lifting-bar, of substantially ypositioning .the dog 29 to engage said bar as soon as ,the lever-handle is turned downwardly. Upon the downward movement of the lever handle the dog 29 first `engages the lifting-bar 2() and elevates the same slightly so as to relieve the loa-d from the dog or pawl 30, and thereupon the arm of the spring 53 turns the plate -i-S outwardly, and this vacts against the roller or pin 4&7 connected with the dog or pawl 30 and moves said pawl outwardly from the lifting bar, the ,dog or pawl 29 then supporting said bar and the load imposed thereon. Upon the succeeding upward movement of Vthe lever-handle, Vthe liftingbar, supported by the dog or pawl 29, is lowered Yone step `and the dog or `pawl 30 becomes positioned to engage thetooth 28 next above the one it lhad previously engaged so that it may support s aid bar on the downward movement of the lever-handle or until the dog 29 has ascended a space equal to one space of the lifting bary and ,then moved inwardly to support said bar and uic-ve the same slightly in an upward direction so as to relieve the load from the pawl or dog 30 and permit said dog- 30 to he retracted troni the bar ,20 by the plate 48 under the action of the spring-arm against the lip 55. The oscillatory movement of the handle-bar is continued with the pawls alternately engaging the lifting bar 20, each always one tooth above the tooth it had previously engaged, until the load has been lowered sufficiently to relieve its strain from 0d the bar 20, and at that time the lifting bar 20 may be worked downwardly by the action of the lever-handle until it has reached its eXtreme lower position, or, at such time, the operator may withdraw the bar G0 from the socket 58 and push the same against the exposed end of the frame 70, thereby driving said frame inwardly against the arm 68 of the dog 29 and through said dog and plate 48 moving said dogs or pawls outwardly from the lifting bar, allowing said bar to automatically drop to its lowest position.

i The setting-lever 64 and plates 48 and 50 are ot' special importance when it is desired to lower the lifting-bar by a step by step movement on the usual oscillatory movement being imparted to the lever-handle. During the upward movement of the lever handle the dog or pawl 29 and plates 48 and 5() move downwardly, and due to the shape ot the upper end of the plate 48 the arm 52 of the spring 58 is permitted, at this time, to turn the upper portion ot' said plate 48 outwardly or toward the front, and during the downward movement of the lever-handle the forwardly curved protuberance or cam edge of the plate 48 is caused, after the dog or pawl 29 has engaged and slightly lifted the lifting-bar, to ride against the pin or roller 47 connected with the dog or pawl 30 and turn said pawl outwardly Jfrom the lifting bar. rlhe plate 48 is af cam-plate because on its upward movement it acts as a cam against the roller or pin 47 connected with the dog or pawl 30; and during the upward movement of the lever-handle the plate 48 is acted on by the spring 53 to move outwardly in a direction from the lifting bar, but at this time said plate 48 has no effect on the dog or pawl 30 because its upper inwardly bent portion then rides idly against the aforesaid roller or pin 47. On the upward movement ot the dog or pawl 29 the same operates through the pivot 49 and pin 57 to force the plate 48 upwardly so that its curved edge will ride inwardlv v against the pin 47 connected with the pawl 30 for iinally retracting said dog 0r pawl 30 'from the lifting bar, and on the downward movement of said dog or pawl 29 and plate 48, the plate 48 is turned outwardly by the spring-arm 52 and the upper arm 63 of the spring 60 is gradually freed to move the pawl or dog 30 against the lifting-bar.

On they down-stroke of the lever-handle, the plate 48 becomes lifted and is turned inwardly toward the lifting-bar, and on the first portion of said stroke of the leverhandle the dog 29 is moved against the bar Lea'aoee 20, and then on the continued downstrolre ot said lever-handle the dog 29 lifts the bar 20 so that the plate 48 may complete its movement and retract the dog 30, the bar 20 then being supported by the pawl or dog 29; and then on the upstrolre of the leverhandle, the dog 29 descends with the bar 20 and load imposed thereon and carries with it the plate 48, which turns outwardly under the it'orce of the spring-arm 52 and vfinally permits the spring-arm 63 to restore the dog or pawl into engagement with the lifting-bar 20 to support the same preparatory to the lever-arm being again turned downwardly to carry the dog Q9 upwardly to engage the next higher-up tooth of said bar and also to again effect the release of the pawl or dog 30 from the bar 20.

The operation just above outlined continues so long as the user of the jack desires to lower the lifting bar by the oscillatory motion of the lever-handle.

W hat claim as my invention and desire to secure by Letters Patent is:

l. A jac r comprising a casing and base, a vertical toothed bar mounted in said casing to support the load, an actuating hand lever pivotally mounted at its inner portion between the sides oit said casing, a pawl having a pin on its side and pivotally mounted on the inner end of said actuating lever and operable therefrom and adapted to engage said bar, and a second pawl pivotally mounted between said sides and adapted to engage said bar while the other or first pawl is disengaged operatively therefrom, said second pawl having' a projecting arm combined with a cam-plate pivotally mounted adjacent to the side of said rst pawl and having an upper portion to engage said arm and a lower angular portion containing an opening receiving said pin on said first pawl, and a spring engaging said cam-plateand acting to turn the upper portion of said pla-te outwardly against said arm ot said second pawl, said cam plate having an edge to ride against said arm when said plate is moved upwardly and withdraw said second pawl from said toothed bar and to recede from said arm when moved downwardly and thereby permit said second pawl to engage said bar and support the load until the iirst pawl is again moved upwardly and has engaged said bar, whereby on the oscillator-vv movement ot the actuating lever the liftingbar becomes lowered.

2. A jack comprising a casing and base, a vertical toothed bar mounted in said casing to support the load, an actuating` hand lever pivotally mounted at its inner portion between the sides of said casing, a pawl having a pin on its side and pivotally mounted on. the inner end oi said actuating lever and operable therefrom and' adapted to engage said bar, and second pawl pivotally mounted between said sides and adapted to engage said bar while the other or first pawl is disengaged operatively therefrom said seoond pawl having a projecting arm, combined with a cam-plate pivotally mounted adjacent to the side of said first pawl and having an upper portion to engage said arm and a lower angular portion containing an opening receiving said pin on said rst pawl, a spring engaginON said cam-plate and acting to turn the upper portion of said plate outwardly against said arm or" said second pawl, said cam-plate having an edge to ride against said arm when said plate is moved upwardly and withdraw said second pawl from said toothed bar and to recede from said arm when moved downwardly and thereby permit said second pawl to engage said bar and support the load until the first pawl is again moved upwardly and has engaged said bar, and a setting lever for controlling the action of said spring on said cam-plate.

3. A jack comprising a casing and base, a vertical toothed bar mounted in said casing to support the load, an actuating hand lever pivotally mounted at its inner portion between the sides of said casing, a pawl having a pin on its side and pivotally mounted on the inner end of said actuating lever and operable therefrom and adapted to engage said bar, and a second pawl pivotally mounted between said sides and adapted to engage said bar while the other or iirst pawl is disengaged operatively therefrom, said second pawl having a projecting arm, combined with al cam-plate pivotally mounted adjacent to the side oi said first pawl and having an upper portion to engage said arm and a lower angular portion containing an opening receiving said pin on said irst pawl, a spring engagino1 said cam-plate and acting to turn the upper portion of said plate outwardly against said arm of said second pawl, said cam-plate having an edge to ride against said arm when said plate is moved upwardly and withdraw said second pawl from said toothed bar and to recede from said arm when moved downwardly and thereby permit said second pawl to enga-ge said bar and support the load until the first pawl is aga-in moved upwardly and has engaged said bar, and means operable from without said casing for releasing said bar to drop.

il. A jack comprising a. casing and base, a vertical toothed bar mounted in said casing to support the load, an actuating hand lever pivotally mounted at its inner portion between the sides of said casing, a pawl having a pin on its side and pivotally mounted on the inner end of said actuating lever and operable therefrom and adapted to engage. said bar5 and a second pawl pivotally mounted between said sides and adapted to engage said bar while the other or iirst pawl is disengaged operatively therefrom, said second pawl having a projecting arm, combined with a cam-plate pivotally mounted adjacent to the side of said iirst pawl and having an upper portion to engage said arm and a lower angular portion containing an opening receiving said pin on said first pawl,

a spring engaging said cam-plate and acting to turn the upper portion ot said plate outwardly against said arm of said second pawl, said cam-plate having an edge to ride against said arm when said plate is moved upwardly and withdraw said second pawl from said toothed bar and to recede from said arm when moved downwardly and thereby permit said second pawl to engage said bar and support the load until the first pawl is again moved upwardly and has engaged said bar, an arm extending downwardly from said first pawl, and a movable frame within said casing in near relation to said downwardly extending arm and having an exposed portion to be subjected to pres sure when said frame is to be forced against said arm 'for effecting the release of said bar to drop.

a acl; comprising a casing and base, tical toothed bar mounted in said casing tor supporting the load, an actuating or pivotally mounted at its inner ietween the sides oi.l said casing, a pant, pivotally mounted on the inner end ot L`id actuating lever and operable therefrom and adapted to engage said har7V a second pawl pivotally mounted between said sides and adapted to engage said bar while the main pawl is disengaged operatively therefrom, a plate pivotally mounted a 'leent to the side o't said main pawl so to move therewith and having an edge in engagement with said second pawl. and a spring engaging-isaid piate and acting to turn the same against said second pawl. raid edge being a cam to ride against said second pawl when said plate is inoved upwardly and withdraw said second pawl from said toothed bar and to recede from said lpawl when said plate is moved downwardly and thereby permit said second pawl to engage said bar and support the load until the main pawl is again moved upwardly and has engaged said bar, whereby on the oscillatory movement of the actuating lever the lifting bar becomes lowered.

6. A jack comprising` a casing and hase. a vertical toothed bar mounted in said casing for supporting the load, an actuating hand lever pivotally mounted at its inner portion between the sides of said casing, a main pawl pivotally mounted on the inner end oi' said actuating lever and operable therefrom and adapted to engage said bar, a second pawl rivotally mounted between said sides and adapted to engage said bar while the main pawlis disengaged operatively therefrom, a

plate pivotally mounted adjacent to thix side ol said main pawl so as to move therewit and having an edge in engagement witl sa second pawl7 and a spring engagingl ,sa plate and acting to turn the same against said second pawl, said edge being a cam to ride against said second pawl when said plate is moved upwardly and withdraw said second pawl :trom said toothed bar and to recede trom said pawl when said plate i moved downwardly and thereby permit saii second pawl to engage said bar and support the load until the main pawl is again moved upwardly and has engaged said bai: whereby on the oscillatory movement ot the actuating' lever the lifting bar becomes lowered, combined with a manually operative setting-lever for controlling the action ot' said spring on said cani-plate.

7. A jack comprising av casing and base, a vertical toothed bar mounted in said casing for supporting the leach an actuating hand lever pivotally mounted at its 'inner portionbetween the sides ot said casing'a a main pawl pivotally mounted on the inner end ot said actuating lever and operable therefrom and adapted to engage said bar, a second pawl pivotally mounted between said sides and adapted to engage said bar while the main pawl is disengaged operatively therefrom, a plate pivotally mounted adjacent to the side of said main pawl so as to move therewith and having an edge Vin engagement with said second pawl, and

a spring engaging said plate and acting to turn the same against said second pawl said edge being a cam to ride against said second pawl when said plate is moved upwardly and withdraw said second pawl troni said toothed bar and to recede from said pawl when said plate is moved downwardhv and thereby permit said secondpawl to engage said bar and support the load until the main pawl is again moved upwardly and has ougaged said bar, whereby on the oscillatory movement ot the actuating lever the litting bar becomes lowered, combinl1 means operable from without said -f releasing' said bar to drop.

8. il jack comprising a casing and base, a vertical toothed bar mounted in .aid casing for supporting the load, an actuating hand lever pivotally mounted at its inner portion between the sides of said casing, a main pawl pivotally mounted on the inner end of said actuating lever and operable Jtherefrom and adapted to engage said bei a second pawl pivotally mounted betw said sides and adapted to engage said while the main pawl is disengaged one atively therefrom, a plate pivotally mounted mljacentl to the side of said main pawl so as to move therewith and having an edge ,in engagement with said second pawl7 and a spring engaging said plate and acting to turn the same against said second pawi, said edge being a cam to ride against said second pawl when said plate is moved npwardly and withdraw said `second nav-:l trom said toothed bar and to recede 't' said pawl when. said plate is moved d` .vardly and thereby permit said second i to engage said bar and support the load until the main pawl is again moved upwardly and has engaged said bar, whereby on the oscillatorj movement ot the a ing lever the lifting bar becomes lon combined with an arm connected with said main pawl, and a movable 'frame within sa 1d casing and having an exposed portion to ne subject-ed to pressure for moving said trame against said pawl-arm to thereby release said bar to drop.

Signed at New York, in the county et New York, and State of New York, this 23rd day of May A. D. 1917.

PAUL W. SCHlElillN.

CHAS. C. GILL.

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