US1195261A - parkin - Google Patents

Description

W. H. PARKIN.

LIFTING JACK.

APPLICATION FILED MAR. 13. I915. 1,195,261. Patented Aug. 22, 1916.

2 SHEETSSHEET WITNESSES: llVI/E/VTOR A TTOR/VE VS W. H. PARKIN.

LIFTING JACK.

APPLICATION FILED 1111111. 13, 1915.

1,]. 95,26 1 Patented Aug. 22, 1916.

2 SHEETSSHEET 2.

ME NnRnls rsrsns co.. PNDTO-LITNO WASHINGYUN. n. c.

WALTER I-I. PARKIN, 0F NILES, MICHIGAN, ASSIGNOR TO NATIONAL STANDARD COMPANY, OF NILES, MICHIGAN.

LIFTING-J'ACK.

Application filed March 13, 1915.

To all whom it may concern:

Be it known that I, WALTER H. PARKIN, a citizen of the United States, residing at Niles, in the county of Berrien and State of Michigan, have invented certain new and useful Improvements in Lifting-Jacks, of which the following is a specification.

This invention relates to improvements in lifting jacks.

The main objects of this invention are: First, to provide an improved lifting jack in which the parts are simple in form and readily assembled and one in which the parts are not likely to be injured or disarranged in handling or transporting, as in an automobile. Second, to provide an improved reversing jack which is positive in operation and is quickly adjusted for raising or lowering. Third, to provide an improved lifting jack having these advantages which is simple and economical in structure and strong and durable in use.

Further objects and objects relating to details and economies of construction and operation will definitely appear from the detailed description to follow.

I accomplish the objects of my invention by the devices and means described in the following specification.

The invention is clearly defined and pointed out in the claims.

A structure which is a preferred embodiment of my invention is clearly illustrated in the accompanying drawing forming a part of this specification, in which:

Figure I is a rear perspective view of my improved lifting jack. Fig. II is a detail front elevation showing the arrangement of the actuating lever and other parts within the standard housing. Fig. III is a detail vertical section on a line corresponding to line 33 of Figs. II and V, the reversing member being shown in inoperative position. Fig. IV is a similar detail vertical section with the reversing member in operative position, the parts being shown by full lines in the position occupied when the lever is in its raised position. Fig. V is a detail section on the line corresponding to the broken line 55 of Fig. III. Fig. V1 is a detail vertical section on a 11119 orresponding to line .,6-.. .of Fig. V.

Specification of Letters Patent.

Patented Aug. 22, 1916.

Serial No. 14,204..

In the drawing, similar reference characters refer to similar parts throughout the several views, and the sectional views are taken looking in the direction of the little arrows at the ends of the section lines.

Referring to the drawing, the frame or standard 1 is provided with a suitable way for the rack bar 2 which is provided with a suitable head 3 at its upper end and step 3 on its rear side. The standard is also pro vided with a housing 1 having a downwardly offset recess 5 at one side of the rack bar. This recess is preferably offset rear" wardly providing a shoulder 6 in the front wall of the housing. The actuating lever 7 is slotted at its inner end, the shank only of the lever being shown. The lever is mounted on a pivot 8 arranged through the slot ted portion thereof. The pawls 9 and 10 are arranged in the slot of the lever. The pawl 9, which is the holding pawl, is mounted on the pivot 8 for the lever, while pawl 10, which is the lifting pawl, is mounted on the pivot 11 disposed on the lever at the inner side of its pivot 8 so that as the lever is rocked on its pivot the pawl 10 is raised and lowered.

The pawls are held yieldingly in engage ment with the rack by means of the coiled springs 12 which are arranged on the pivots at one side of the pawls within the lever slot as shown in Figs. V and VI. The springs are provided with arms 13 at one end which engage the pawls and with arm-like extensions 14 at the other end which engage the lever, the extensions 14 resting within the lever in the structure shown. A web 15 extends across the lower edge of the slot to reinforce the lever.

The pawls 9 and 10 are provided with laterally projecting pins 17 and 18 respectively. The reversing member 19 is mounted on the lever pivot 8 at one side of the lever to coact with these pins. The inner end of the reversing member 19 is, in the structure illustrated, provided with an offset 20 having a groove 21 therein. The reversing member is actuated by the U-shaped spring 22 which is arranged with its bight end in the recess 5, the bottom of the recess being rounded to re ceive the spring, see Fig. III. The rear arm 2.3 of the spring rests against the rear wall of the recess which is provided with a groove 24 for the spring, the upper end of the spring being below the shoulder 6, so that the spring is effectively retained and supported in position with its free arm engaging the groove 21 in the reversing member.

The reversing member is provided with a handle 25 which projects from the housing for convenience in manipulation. \Vith the parts thus arranged the springs serve to actuate the reversing member when in one position, that is, with its inner end above the horizontal plane of its pivot, as best shown in Fig. IV, and also serves to hold it in inoperative position when its inner end is swung below the horizontal plane of its pivot, best show-n in Fig. III. With the re versing member in its inoperative position, as shown in Fig. III, the oscillation of the lever 7 will raise the rack.

To reverse the rack, that is to adjust the jack so that the rack is lowered when the lever is operated, the reversing member is shifted to the position as shown in Fig. IV, in which position it alternately acts on the pawls to cause them to engage and disengage the rack as the lever is operated.

This operation of the parts is as follows:

Assuming the parts to be in the position as shown by full lines in F i IV, in which the lifting pawl is engaged and the holding pawl disengaged, the upward stroke of the lever lowers the lifting pawl 10 and owing to the load on the pawl its pin engaging the reversing member swings it downward to the position shown by dotted lines in Fig. IV, against the tension of its actuating spring, allowing the holding pawl to swing into engagement with the rack and receive the load. When the load is released from the lifting pawl the reversing member actuating spring 22 overcomes the pawl spring and disengages the lifting pawl from the rack carrying it to the position shown by dotted lines in Fig. IV, and holding it out of engagement with the rack during the upstroke of the lever. As soon as the load is shifted from the holding pawl to the lifting pawl the reversing member disengages the holding pawl from the rack.

The reversing member is provided with a notch 26 into which the pin 18 rests when the lever is at the end of its upstroke, and with a shoulder 27 which engages the pin 17 011 the pawl 9 when the lever is at the end of its downstroke.

WVith the parts thus formed and arranged they are simple and economical toproduce and easily assembled and the structure is also very compact and the parts are protected so that they are not likely to become injured or disarranged. I have illustrated and described my improvement'in the form in which I have embodied the same in a small or automobile jack. My improvements are, however, desirable for embodiment in jacks for other uses.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is: j

1. In a lifting jack, the combination" of a rack bar, a standard having a slideway for said rack bar and a housing with a downwardly offset recess at one side of the rack bar, there being a groove in the rear wall of the recess and a shoulder at the upper end thereof, the lower end of the recess being rounded, a lever slotted at its inner end, a pivot for said lever arranged through its slottedend and through said housing, a pair of pawls having laterally projecting pins arranged in the slot of said lever, one of said pawls being arranged on the lever pivot and the other on a pivot disposed on the lever at the inner side of its pivot, coiled springs arranged on said pivots at one side of the pawls and within the lever slot, one end of the springs being engaged with the pawls and the other ends having extensions engaging the lever, a reversing member mounted on said lever pivot at the side of the lever to engage said pins on said pawls, the inner end of the lever being offset toward the pawls and grooved, and a U-shaped spring arranged in'said recess with its bight resting in the bottom thereof and with its rear arm below said shoulder and engaging said groove in the rear wall of the recess, its front arm being engaged with the groove in the end of said reversing member and yieldingly supporting it in operative position to eoact with said pawls when its inner end is above the horizontal plane of its pivot and holding it in inoperative position when its inner end is below such plane.

2. In a lifting ack, the combination of a rack bar, a standard having a slideway for said rack bar and a housing with a downwardly offset recess at one side of the rack bar, a lever slotted at its inner end, a pivot for said lever arranged through its slotted end and through said housing, a pair of pawls arranged in the slot of said lever, one of said pawls being arranged on the lever pivot and the other on a pivot disposed on the lever at the inner side of its pivot, coiled springs arranged'on said pivots at one side of the pawls and within the lever slot, one end of the springs being engaged with the pawls and the other ends having extensions engaging the lever, a reversing member mounted on said lever pivot atthe side of the lever to coaot with said pawls, and a U-' shaped spring arranged in said recess with its bight resting in the bottom thereof and with its rear arm engaging the rear wall of the recess, said reversing member being slidably engaged with the free arm of said spring so that it is actuated thereby to coact with said pawls when its end engaged with said spring is swung to a position at one side of its pivot and is held in inoperative position by said spring when its end engaged therewith is swung. to the opposite side of its pivot.

23. In a lifting jack, the combination of a 'aek bar, a standard having a slideway for said rack bar and a housing with a downwardly offset recess at one side of the rack bar, there being a groove in the rear wall of the recess and a shoulder at the upper end thereof, the lower end of the recess being rounded, a lever slotted at its inner end, a pivot for said lever arranged through its slotted end and through said housing, a pair of pawls having laterally projecting pins arranged in the slot of said lever, one of said pawls being arranged on the lever pivot and the other on a pivot disposed on the lever at the inner side of its pivot, springs for holding said pawls yieldingly in engagement with said rack bar, a reversing member mounted on said lever pivot at the side of the lever to engage said pins on said pawls, the inner end of the lever be ing offset toward the pawls and grooved, and a U-shaped spring arranged in said recess with its bight resting in the bottom thereof and with its rear arm below said shoulder and engaging said groove in the rear wall of the recess, its front arm being engaged with the groove in the end of said reversing member actuating the reversing member when in one position and holding it in inoperative position when in another position.

4. In a lifting jack, the combination of a rack bar, a standard having a slideway for said rack bar and a housing with a downwardly offset recess at one side of the rack bar, a lever slotted at its inner end, a pivot for said lever arranged through its slotted end and through said housing, a pair of pawls arranged in the slot of said lever, one of said pawls being arranged on the lever pivot and the other on a pivot disposed on the lever at the inner side of its pivot, springs for holding said pawls yieldingly in engagement with said rack bar, a reversing member mounted on said lever pivot at the side of the lever to coact with said pawls, and a U-shaped spring arranged in said recess with its bight resting in the bottom thereof and with its rear arm engaging the rear wall of the recess, said reversing member being slidably engaged with the free arm of said spring so that it is actuated thereby to coact with said pawls when its end engaged with said spring is swung to a position at one side of its pivot and is held in inoperative position by said spring when its end engaged therewith is swung to the opposite side of its pivot.

5, In lifting jack, the combination of a rack bar, a standard having a slideway for said rack bar and a housing with a downwardly oil'set recess at one side, a lever slotted at its inner end, a pivot for said lever arranged through its slotted end and through said housing, a pair of pawls arranged in the slot of said lever, one of said pawls being arranged on the lever pivot and the other on a pivot disposed on the lever at the inner side of its pivot, springs for holding said pawls yieldingly in engagement with said rack bar, a reversing member pivotally mounted on the lever pivot to alternately engage said pawls, and a U-shaped actuating spring therefor arranged with its bight resting in said recess and with one arm free, said reversing member being slidably engaged with the free arm of said spring so that it is actuated thereby to coact with said pawls when its end engaged with said spring is swung to a position at one side of its pivot and is held in inoperative position by said spring when its end engaged therewith is swung to the opposite side of its pivot.

63. In a lifting jack, the combination of a rack bar, a standard having a slideway for said rack bar and a housing with a downwardly ofl'set recess at one side, a lever pivoted within said housing, a pair of pawls, one of said pawls being pivotally mounted on said lever and the other being pivotally supported to coact with said rack bar, springs for holding said pawls yieldingly in engagement with said rack, a pivotally mounted reversing member arranged to alternately engage said pawls, and a U-shaped spring arranged with its bight end in said recess with one arm free, said reversing member being slidably engaged with the free arm of said spring so that it is actuated thereby to coact with said pawls when its end engaged with said spring is swung to a position at one side of its pivot and is held in inoperative position by said spring when its end engaged therewith is swung to the opposite side of its pivot.

7. In a lifting jack, the combination of a rack bar, a standard having a slideway for said rack bar, a pivoted lover, a pair of pawls, one of said pawls being pivotally mounted on said lever and the other being pivotally supported to coact with said rack bar, springs for holding said pawls yieldingly in engagement with said rack, a pivotally mounted reversing member arranged to alternately engage said pawls, and a blade spring disposed at the inner side of the reversing member pivot to extend above and below its horizontal plane and in engagement with the inner end of said reversing member yieldingly supporting it in operative position to coact with said pawls when its inner end is above the horizontal plane man;

of its pivot and holding it in inoperative my hand and seal in the presence of two position when its inner end is below such Witnesses.

plane, the inner end of said reversing mem- WALTER H PARKIN L her having sliding engagement With said f spring permitting its adjustment from one Witnesses:

ANNA MILLER,

position to the other.

HELEN form.

In Witness whereof, I have hereunto set Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C.

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