US 1964624 A
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June 26, 1934. M. DWORK 1,964,624
Filed Jan. 20, 1932 2 Sheets-Sheet l INVENTOR (2x Dwork, a Mi ATTORNEY www 5 129W June 26, 1934. M. DWORK 1,964,624
Filed Jan. 20, 1932 2 Sheets-Sheet 2 INVENTOR l4 J/aac ,DWc r/Q MVQ ATTORNEY Patented June 26, 1934 UNITEDSTATES PATENT torrics V Max Dwork, Brooklyn, N. Y. I Application January 20, 1932, s rial No. 587,769 15 Claims. (or. 254-450) This invention relates to improvements in jacks particularly intended for use in connection with automobiles and other vehicles, but by no means restricted to such use, and its objects are as follows:-
First, to provide a jack of the type having a flexible lifting element of which one end is wound on a turnable winding shaft, therebeing a brake mechanism so combined with the actuating means of the shaft that the act of applying the brake will first serve to render the actuating means inoperative and then apply the braking force to the shaft so that the rate of unwinding of the lifting element can be controlled.
Second, to provide a jack which includes an element which is extensible in respect to a standard, in reference to which standard said element can be held at any starting point by means of a yoke which is adjustably clamped along the standard for the'purpose.
*ThirdQtc provide a grapple to be used in conjunction with the flexible lifting element, said grapple being especially adapted for use in connection with the jack, to which end it embodies certain locking means which assume a locking position in reference to the lifting element when the weight is applied. Y
Other objects and advantages will appear in the following specification, reference being had to'the accompanying drawings in which Figure 1 is a side elevation of the improved jack, illustrating its use for lifting the chassis of an automobile;
Figure 2 is a detail perspective viewof the the winding shaft when the actuating means of that shaft has been rendered inoperative.
Figure 6 is a detail vertical section, particularly illustrating the use of the yoke by means of which the extensible element can be adjusted to various starting points.
Figure '7 is a cross section taken on the line 7 of Figure 6.
Figure 9' is an elevation of theimproved grapple, showing it inone of its two closed positions. v
Figure 10 is a similar view of the grapple showing it in its second closed position.
One of the main purposes of the improved jack is to facilitate the jacking up of an automobile so' as to enable putting the jack in place without compelling the operator to get down to the ground leveland thereby soil his clothing as in the usual effort of workinga jack under the spring supports. As is presently brought out, the attachment of the jack is made to a projecting part of the chassis, the extra height being provided for by incorporating an element in the jack which is extensively adjustable inreference to a standard by meansof a-certai'n yoke. It must'be understood that the jack' is not limited to this particular use, because it can be employed for many other purposes such as jacks of other types are commonly employed for.
In Figure 1 the jack, generally denoted 1, is illustrated as comprising an element 2 which is extensible in reference to a standard 3, the relative adjustments being maintained-by a yoke 4 (Fig. 8) on which the element 2 rests and which can be set any where along the series of notches 5, 6 on opposite sides of the standard (Fig. 6). The adjustment of the yoke 4 along the standard 3 varies the altitude of the element 2 and the point from which the lifting operation will be started.
The yoke 4 comprises a rectangular band which is sufficiently over-sized in'one direction to make: room for the adjustments of a follower '7 (Figs. '7 and 8) which has end lugs 8 supported and guided by slots 9 in the opposite sides of the yoke. A screw 10, threaded in the adjacent end of the yoke. 4, has a rotatable connection 11 with the follower 7 so that the turning of the screw will move the follower back and forth and so either engage or disengage the tooth 12 with one of the notches 5 (Fig. 6).
At the opposite end of the yoke 4 there is a correspondinginturned tooth 13 which is intended to engage one of the notches'fi (Fig. 6). This end also carries a fingerpiece 14 by which and by the screw 10 the yoke 4 is lifted or lowered to new adjustments. It is readily seen that when the follower 7 is moved out far enough the yoke 4 can be moved'to any desired point along the standard 3, whereupon the screw 10 is turned in until the connection is made as shown in Figure 6. A leaf spring 14*, attached to one side of the yoke, presses against the standard 3 to hold the yoke firmly so that it will not fall down when loosened.
When there is no necessity for using the yoke 4 it will be pocketed within the confines of a wall 15 built up around the bottom of the standard 3 on the base 16. The standard 3 is integral with the base, and in practice the latter will be sufiiciently extended and of such a design as to provide an adequate support on the floor or ground. The wall 15 has an open side as at 17, and that portion opposite to the side is recessed at 18 to accommodate the fingerpiece 14.
The extensible element 2 includes a sleeve which has a sliding fit on the standard 3. Said element is slid along the standard when its rest yoke 4 is adjusted as stated before. The chassis 19, herein used as an example of the object to be lifted, is raised with respect to the element 2 by the following means:A winding shaft 20, journaled across the upper open part 21 of the sleeve which constitutes a mounting by which the'shaft is supported, fixedly carries a ratchet wheel 22 against which a pawl 23 acts with a step motion to give, the shaft 20 successive turns in one direction, thereby to wind a strap 24 or other flexible lifting element on the portion 25 of the shaft 20 (Fig. 3)
which serves as a drum. The shaft 20, ratchet wheel 22 and strap 24 chiefly comprise a structure to do lifting. That end of the shaft 20 which extends well outside of the open part 21 provides a journal both for'a lever base 26 and a brake arm 27. The base 26 has arms 28, 29 (Fig. 1). The arm 28 is forked at 39 (Fig. 3) to provide an adequate support for the pivot pin 31 of the pawl 23. The pawl is pressed toward the ratchet wheel 22 by a spring 32. The pawl has a roller stud 33 on the outside.
A lever 34 (Fig. 1) has a socketed end to receive the arm 29 to which the lever is secured by an appropriate screw 35. The screw is attached to the lever 34 by a chain 36 so that it will not be lost. The free extremity of the lever carries a removable cross bar 37 which is held in place by a thumb screw 38. This cross bar provides an extended grip so that the lever may be operated easier. When the jack is takenpdown the lever 34 is removed by loosening the screw 35.
So far it will be understood that working the lever 34 up'and down will cause a counterclockwise turning of the shaft 20 with a winding up of the flexible element 24 as the result, the lever and its pawl normally'being in gear, so to speak, with the foregoing lifting structure to work said structure. This element runs over an idler 39 which is mounted on a cross pin 40 in the closed top 41 of the element2. The closure 41 affords the advantage of covering and protecting the top part of the strap 24. If the strap were exposed at this point there would be the possibility of its becoming injured in rough handling of the jack.
The free end of the strap 24 carries a clip 42 from which a grapple 43 is loosely suspended (Figs. 9 and 10). This clip comprises a piece of metal, angled in the shape of an L (Fig. 1) with slots in each of the flanges. The strap 24 is passed through one of the slots and then riveted down. The other slot receives the upper ends 44, 45 of the grapple hooks 46, 47. These hooks are pivoted together at 48 at a point below the clip 42 so that it becomes necessary to lower the clip to a point adjacent to the pivot 48, or to raise the grapple until the pivot nears the clip, before the grapple hooks can be opened wide enough to release the chassis 19.
The respective upper ends 44, 45 are ma'dewith oppositely directed pairs of hooks 49, 50. These hooks coact with the ends of the clip 42 to secure the grapple hooks 46, 47 in either of two degrees of closure. The opposite faces of the hooks 49, have slightly projecting studs which are intended to act as stops against the clip to prevent any possibility of the grapple dropping out.
In order to engage the chassis 19 the grapple 43 is opened by slipping it upwards in the clip 42 and swinging the grapple hooks 46, 4'7 wide on the pivot 48. The grapple is then closed by moving the clip upwards over the outer curved surfaces 52. Thereupon one or the other set of the pairs of hooks 49, 50 can be brought into engagement with the ends of the clip 42 depending on whether it is desired to hold the grapple 43 as in Figure 9 or in Figure 10. If the first degree of closure is to be maintained the left hook 49 of the grapple hook 46 and theright hook 50 of the grapple 47 are coupled with the ends 42 (Fig. 9). If the second degree of closure is to be maintained the right hook 50 of the grapple hook 46 and the left hook 49 of the grapple hook 47 are coupled with the ends of the clip 42 (Fig. 10).
A back-check pawl 53 prevents reverse or clockwise turning of the shaft 20 as long as it is in engagement with the ratchet wheel 22. This pawl is pivoted at 54 on the extensible element 2, and the pin which constitutes this pivot also serves as the carrier for a brake frame 55 (Fig. 2). This frame comprises arms 56, 57, the outer ends of which are fixedly connected by a shaft 58 which extends far enough beyond the arm 57 to pass through a slot 59 in the brake arm 27 (Fig. 4), then to provide a movable mounting for the near end 60 of the pawl 53 and finally to support a crotch arm or release member 61 which has a crotch'62 at its upper end. The crotch 62 receives the roller stud 33 both to limit the downward movement of the lever 34 and to serve as the meansfor raising the pawl 23 in the act of applying the brake.
The foregoing support of the arm 61 on the shaft 58 is pivotal for the purposes of applying the brake. proper position by a limiting piece 63 which fits around the winding shaft 20 and carries a stud 64 to occupy a slot 65 in the crotch arm 61. A spring 66 presses on the pawl 53 in such a way as to normally keep it in engagement with the ratchet wheel 22. A spring 6'7 (Fig. 2) presses on the brake frame 55 in such away as to normally keep the frame 55 against a stop 79 on the side of the jack.-
A brake lever 68 is loosely pivoted at 69 (Fig. 2) tothe arm 57 of the brake frame. This arm is so formed as to provide a shoulder 70 with. which a lug '11 on the brake lever 68 is engageable (Fig. 5) when the lever 68 is lifted in the act of applying the brake. This brake chiefly comprises a slot 72 (Fig. 4) in the upper end of the arm 27, acting as the brake band, and the surface of the winding shaft which acts as the drum. The shaft passes through the slot so that this relationship may be had;
Attention is directed to Figure 1. The chassis 19 has an attached semi-elliptical spring 73 by which the axle 74 of the wheel 75 is supported. Inasmuch as the use of the jack 1 is predicated on the lifting of the chassis 19 it follows that if there were no restraint the spring 73 would sag to an undesired extent before the wheel 75 left the ground. Sag-limiting means is therefore used. This comprises a strap or other flexible element 76 which is looped under the axle and has its The crotch arm 61 is retained in its ends attached to the chassis. by means of an appropriate coupling 7'7. Upon raising. the chassis the spring '73 will sag only as permitted by the element 76. I
. The operation is readily understood. Upon desiring to raise .the chassis 19 the grapple 43 is coupled with it (Fig. 1) in the manner brought out in detail above. The lever 34 is Worked up and down, eachdown stroke causing. a counterclockwise turn of the winding shaft 20 by means of the pawl 23 and ratchet wheel 22. It is the winding up of the flexible element 24, by which the grapple43 is carried, that does the raising of the chassis. Reverse turning of the shaft 20 is prevented by the backcheck pawl 53. r
It will be observed that the entire shaft and actuating means are carried by the extensible element or sleeve 2. The progressively higher adjustments of the sleeve 2 along the standard 3 bring the operating lever successively nearer to the operator so that it comes within easier reach.
the higher the adjustment of said extensible element.
Should it be desired to let the chassis 19 down the brake lever 68 is pulled up. .This brake lever has two purposes, first, to render the foregoing actuating means inoperative, second to apply the brake. In this respect the brake lever is a common operator since its first act is to operate the release means 61 and associated parts, and its second act is to bring the brake means 27 (Fig. 5) into action. Before using the brake lever 68 the operator should see to it thatthe lever 34 has been pushed down as far as possible, in other words, until the rollerstud 33 is saddled in the crotch 62 (Fig. 2).
Now upon lifting the brake lever 68 the first act comprises the engagement of the lug 71 with the shoulder of the brake frame 55 (Fig. 5). Tracing the upward push through the various articulations, there will be a primary lifting of the shaft 58 and of the crotch arm 61. This turns the pawls 53 and 23 away from the ratchet wheel 22.
While these pawls 53 and 23 are being turned away from the ratchet wheel 22 the slot '72 (Fig. 4) is being consumed, so to speak, so that by the time the pawls have been moved away the bottom ofthe slot '72 will have reached the now freed shaft 20 and made contact therewith (Fig. 5). Then it only becomes a matter of either pulling up harder on the brake lever 68 orreleasing the tension in order to so control the shaft 20 that the strap 24 unwinds at the proper speed. Upon letting the lever 68 down and releasing it altogether the foregoing actuating means, particularly the pawls 53, 23 will be restored to engagement with the ratchet wheel 22.
It has already been brought out that any desired starting point for the lifting action of the jack may be established by adjusting the yoke 4 along the standard 3. This yoke will ordinarily sustain the extensible element 2 at a given elevation but said element may be additionally supported by a set screw 78 (Fig. 1) which can be screwed in until its point bites against the standard.
1. In a jack, a turnable winding shaft, a lifting element connected with the shaft, actuating means for turning the shaft in one direction so as to cause a lift by said element, a. brake arm having an opening through which the shaft extends, a release member to render the actuating means inoperative so as to'loosen the shaft for reverse rotation, and means to first operate the release member and second to move the brake arm until a wall of the opening binds against the. shaft to control said rotation. 1
2. In a jack, a turnable winding shaft, a lifting elementconnected with the shaft, a ratchet wheel and pawl device for'turning the shaftin one direction so as to cause a lift by said element, brake means to brake the shaft, a lever to move the brake means to a braking position, and means which isfirst operated by the movement of the lever to disengage the pawl from the ratchet Wheel and so loosen the shaft for reverse rotation.
3. In a jack, a turnable winding shaft, a lifting element connected with the shaft, a ratchetwheelsecured to the shaft, actuating means in cluding a pawl operable against saidwheel to. turn the shaft in one direction and cause a lift by said element, a back-check pawl engaging said wheel to prevent reverse rotation, brake means to brake the shaft during reverse rotation, a lever to move the brake means to a braking position, and means which is first operated by the move-- ment of the lever to disengage both pawls from I said wheel to loosen the shaft for reverse rotation.
' 4. In a jack, a turnable shaft, a lifting element connected with the shaft, means for turning the shaft in one. direction and cause a liftbysaid element, brake means which is inactive during said turning but which is active during free reverse turning, release means to render the turning means inactive, and means which is operable in one movement to first operate the release means to free the shaft, second to bring the brake means into play to control the free reverse turning of the shaft.
ing the other end of the pawl with the brake arm,
and a lever to act on said connection, first to disengage the pawl from the ratchet wheel, second to shift the brake arm against the shaft.
6. In a jack, a turnable shaft, a mounting by which the shaft is supported, a lifting element; connected with the shaft, a ratchet wheel secured to the shaft, a pair of pivoted pawls engaging said wheel, a stud on one of the pawls, a crotch arm pivoted on the other pawl and having a crotch to receive the stud, a brake arm loosely connected at its opposite ends with the crotch arm pivot and the shaft, and a lever to shift the crotch arm pivot thereby to disengage both pawls and then shift the brake arm against the shaft.
7. In a jack, a movable crotch arm having a crotch, a turnable shaft beside which the arm is movable, a mounting by which the shaft is supported, a lifting element connected with the shaft, means for turning the shaft including a pawl with a stud to occupy the crotch, and means loosely connecting the crotch arm with the shaft to limit the movements of the arm.
8. In a jack, a standard having a base, a yoke adjustable along the standard, and a wall on the base spaced from the standard to receive the yoke when not in use.
9. In a jack, a lifting element, a slotted clip carried by an end of said element, a grapple suspended from the clip slot, comprising grapple 15 0 arms having an arrangement of hooks at one end for engaging the ends of the clip to lock the grapple arms in a closed position, and a pivot connecting the arms being movable toward the clip to release the hook arrangement. i
10. In a jack, a turnable windingshaft and a lifting element connected with the shaft, a mounting by which the shaft is supported, actuating means for turning the shaft including a ratchet on the shaft and a pair of pawls, one being an actuating pawl andthe other a back-check pawl,
a brake arm and brake means on it applicable "for turning the shaft including aratchet fixed on the shaft and a pair of pawls engaging the ratchet one being an actuating pawl the other a' back-check pawl, brake means for the shaft, a release member for the actuating pawl, a -movable structure with which the back-check pawl, brake means and release member have common connection, and means for moving said structure to successively disengage the pawls from the ratchet and to apply the brake means to the winding shaft.
12.'In a jack, a lifting element, a slotted clip carried by said element, grapple arms suspended from the clip, and oppositely directed pairs of hooks on each grapple arm, being adjustable in theclip slot so that'sel'ected ones of the pairs of hooks may be engaged with the. ends of the clip.
13. In a jack, a lifting element, a slotted clip carried by said element, grapple arms suspended from the clip, said arms having a pivot by which they are connected, oppositely directed pairs of hooks on the upper end of each arm, the upper ends extending through the clip slot, and outwardly curved surfaces on opposite sides of said upper ends beingxengageable by the ends of the slot in moving the clip from the grapple arm pivot toward said hooks thereby to close the grapple arms, the. selected ones of the hooks being engageable with the ends of the clip to holdthe grapple arms in either of two degrees of closure.
14. In a jack, a structure in the jack to do lifting means which is normally in operative connection and operable to work said structure, brake means for said structure being normally inactive, a, release means to throw the first means out of operative connection and so free the lifting structure, and a commonoperator which isrmovable first to operate the release means and second to bring the brake means into action.
15. In a jack, a turnable shaft, a mounting by which the shaft is supported, a lifting element connected with the shaft, a ratchet wheel secured to the shaft, actuating means carried by said shaft and including a pawl to turn the.
and then shift the brake arm to tighten it on the shaft for a braking effect.
' MAX DWORK.