US1207526A - Jack. - Google Patents

Description

'lPatentedl Dec. 5, 1916.

'0. v. FOWLER.

JACK.

APPLICATION FILED MAY 22. I916.

CHARLES V. FOWLER, 0F LOS ANGELES, CALIFORNIA.

JACK.

Specification of Letters Patent.

Patented Dec. 5, 191 6.

Application filed May 22, 1916. Serial No. 99,036.

To all whom it may concern Be it known that I, CHARLES V. FOWLER, a citizen of the United States, residing at Los Angeles, in the county of Los Angeles and State of California, have invented new and useful Improvements in Jacks, of which the following is a specification.

This invention relates to jacks, and pertains especially to jacks of the ratchet lever yp 1 It is an object of this invention to provide a jack with means whereby the load may be gradually raised or lowered step-by-step at the will of the operator.

1 It is another object to provide a simple means for a jack of the character described, whereby the pawls may be arranged toeither engage theratchet teeth on raising or on lowering as desired.

It is a'further object to provide a jack with a pawloperating means which may be quickly adjusted to throw the pawls into or out of the ratchet teeth as desired, and which does not include springs or other resilient means.

In the accompanying drawing forming a part of this specification, Figure 1 is a side elevation of a jack embodying the features of the present invention, the pawls being in position for lowering an object. Fig. 2 is a fragmentary side elevation in section showing the pawls in position for raising an object. Fig. 3 is a section similar to that shown in Fig. 2, but with the pawls arranged for lowering an object as in Fig. 1; Fig. 4 is a section as seen on the line 44 of Fig. 1. Fig. 5 is a fragmentary detail ofa front elevation of the lifting bar and standard.-

Referring more particularly to the drawing, 6 indicates a base upon which is supported a standard 7. Standard 7 is provided with a bore 8 extending longitudinally thereof. Opening to the bore 8 in diametrically opposite positions are slots 9 and 10 arranged in alinement with the axisof the standard Movably mounted for reciprocation in the standard 7 is a lifting bar 11, the upper end of which carries a head 12 suitable for engaging the object to be lifted or lowered. The lower end of the lifting bar 11 is slotted as indicated at 12, and provided with a transverse pivot pin 13.

Pivotally mounted upon the pivot pin 13 is a lever 14. One end of lever 14 is provided with a handle 15, whereby the lever may be conveniently operated.

' The exterior of the standard 7 adjacent the slots 9 and 10 is provided with a series of teeth or notches 16 and 17 which are adapted to be engaged by pawls 18 and 19 pivotally mounted intermediate their ends upon the lever 14. The upper ends of the pawls are formed of angularly disposed surfaces 20 and 21 forming abutments adapted to be engaged by a pawl block 22.

Pawl block 22 controls the pawls 18 and 19, and has a bore 23 of such diameter that it may freely slide over the standard 7 and may be rotated therearound.

The transverse dimensions of block 22 are greater in one direction than in the other, and the block is so constructed that when positioned with the greater dimension eX- 2 tending from pawl to pawl the under-surface of the block will be in a position to enof and overhang the sides of the pawls. I

thereby preventing rotary displacement of the pawl block, as the lifting bar is raised or lowered. Upon each side of the lever are formed lugs 27 and 28, one for each pawl. These lugs areso positioned that when either end of the bar is inclined downwardly the pawl on the lower end of the bar will be prevented from moving out of engagement with the tooth.

If it is desired to raise an object the jack is placed beneath it with the object resting on the head 12; the pawl block 22 is then disposed with the longest dimension from pawl to pawl or in the position shown in Fig. 2. Upon lifting the bar 14 the pawl 18 rests upon a ratchet tooth, the lever 14 pivoting about the pin 25. The pawl block 22 is raised by reason of the pawl 19 abutting the under-surface thereof. The weight of the pawl block resting upon the abutment 21 will force the pawl 19 inwardly and upon a ratchet tooth 17, as it reaches the upper shoulder thereof. Upon moving the lever bar 14 downwardly the pawl 19 resting upon a tooth. 17 will cause the lever to fulcrum about the pivot pin 26. The pawl 18 engages the block 22 and lifts it, the abutment 21 engaging the pawl block and moving the pawl inwardly to engage a next higher tooth 16. The operation may then be continued step by-step until the object has been raised.

7 To lower an object the pawl block 22 is rotated so that its lesser dimension is disposed from pawl to pawl, as illustrated in Fig. 3. Upon lowering the lever 14 a slight amount the pawl 18 engages the pawl block 22, pawl 19 resting upon a tooth 17 and V V lever bar pivoting about pin 26. The pawl block engages abutment and forces the pawl '18 out of a tooth 16'. By then raising the lever bar the pawl 18 is disengaged from pawl block 22, the latter resting upon it engages the next lower tooth 17; The opera'tion of lowering is continued until pawl 18 isrel'easedand then the lever 14 is raised. Byalternately raising and lowering the lever,the lifting barll is lowered.

If it is desired toquickly lower the lifting bar after an 'objeet has been raised, then 1 the pawl block is'rotated to its position for lowering the bar;*neXt,the2h-and1e 15 is,

raisedso that the pawl block rests upon both pawls thereby forcing them out of en gagement' with theteeth on the standard.

In" this condition the lifting bar is free to move from its'upper to its'lower position, the pawls remaining' o'ut of engagement with theteetha What I claim is:

' 1'. In a lifting jack, the combination of n t a member mounted thereon,a lever pivotally a notched standard, reciprocable lifting secured to said lifting member, a pair of oppositelvdisposed pawls pivotally'mounted intermediate their ends on said lever and 1 adapted to engage the notches on said stand- 1 ard, a pawl block disposed upon' said pawls,

I said. block mounted for rotation, and means thereonten'ding to force'said pawls out of said notches whe'n in engagement with a pawl, and other means on said block tending to force said pawls into said notches when in engagement with a pawl.

2. In a lifting jack, the combination of a notched standard, a reciprocable lifting member mounted thereon, a lever pivotally secured to said lifting member, a pair of oppositely disposed pawls pivotally mounted intermediate their ends on said lever and adap'ted'to engage the notches on said standard, a pawl block disposed upon said pawls, said block having oppositely disposed surfaces for engaging the pawls on adjacent sides of their pivotal point and oppositely disposed surfaces for engaging the pawls upon the opposite sides of their pivotal points. I

3. In a lifting jack, the combination of a notched standard, a reciprocable lifting member mounted thereon, a lever pivotally secured to said lifting member, a pair of oppositely disposed pawls pivotally mounted intermediate their ends on said lever and adapted to engage the notches on said standard, each of said pawls provided on its upper end with abutments, one abutment disposed on each side of the pivotal point, a pawl block disposed'upon said pawls having two oppositely disposed i faces for .engagement with the complementaryabutinents on said pawls, and'another pair of oppositely disposed faces for engagement with the other abutments' on said pawls.

4. In a lifting jack, the combination of a'notched' standard, a reciprocable lifting member mounted thereon, a lever pivotally secured to said lifting member, a pair of oppositely disposed pawls pivotally mounted intermediate their ends on said lever and adapted to engage the notches 011 said standard, each of said pawls provided on its up per end with abutments', one abutment disposed on each side of the pivotal point, a weighted pawl'block having dimensions in transverse directions such that when resting upon, said pawls in' one position it will engage the inner abutinents and when rotated to another position it will engage the outer abutments.

In witness that I claim the foregoing I have hereunto subscribed my name this 12th day of May, 1916.

' CHARLES v. FOWLER.

" flop ies oft1iis'petent may be: obtained for five'cents each, by addressing the Commissioner of Patents,

.7 Washington, D. G.

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