US917874A

US917874A - Lifting-jack.

Info

Publication number: US917874A
Application number: US41593808A
Authority: US
Inventors: William R Johnson
Original assignee: Individual
Current assignee: Individual
Priority date: 1908-02-14
Filing date: 1908-02-14
Publication date: 1909-04-13
Anticipated expiration: 1926-04-13

Description

W. R. JOHNSON, LIFT ING JACK. APPLICATION FILED FEB. 14, 1908.

Patented Apr. 13, I909.

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WILLIAM R. JOHNSON, OF NEWPORT, NEBRASKA.

LIFTING-JACK.

Specification of Letters Patent.

Patented April 13, 1909.

Application filed February it, 1908. Serial No. 5,938.

T all whom it may concern:

Be it known that 1, WILLIAM R. JOHNSON, a citizen of the United States, residing at Newport, in the county of Rock, State of Nebraska, have invented certain new and useful Improvements in Lifting-lacks; and 1 do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled the art to which it appertains to maize and use the same.

This invention relates to lifting jacks and more particularly to that class which are constructed to lift from above, it being understood that the j acli may be put to a number of different uses where such power or lifting action is required.

The primary object of the invention is to provide a simple and very durable construction of ja k of this class and one embodying a novel arrangement and construction of parts and devices or elements tending to render the instrument adaptable to numerous uses under various conditions.

Such features of the invention as go to make up the generally useful structure aimed at, wfll be more fully described and pointed out in the description which is to follow, the claim, and the dra vings, in which,

Figure 1 is a side elevation of the acli showing the lever in engagement with one of the teeth of the rack bar of the jack and showing in dotted lines the position of the lever when moved to elevate the said rack bar, Fig. 2 is a top plan view of the jack, Fig. 3 is a front elevation, Fig. 4 is a rear elevation, Fig. 5 is a vertical longitudinal sectional view, and, Fig. 6 is a vertical transverse sectional view.

The jack embodied in my invention is shown in the drawings as comprising a frame made up of arched side members 7 which are connected in spaced parallel relation at their upper ends by means of bolts 8 carrying spacing sleeves and at their lower ends by means of bolts 9 which in addition to being engaged through the legs of the arched members are passed through the upper ends of supporting legs or standards 10 received between the legs of the arched members and designed for the support of the device. A brace bar 11 connects the legs of one of the arched side members and is held in place by one pair of the upper bolts 9. The legs of the arched side members and the supporting legs or standards 10 converge upwardly and consequently so much of the machine as has been described is in the form of an inverted ii.

Held against the inner or opposed faces of the frame members 7 their upper ends by means of the bolts 9, are plates 12 and these plates are formed at their upper edges with inwardly directed flanges 13 the edges of which are spaced. Received between the said edges of the flanges 13 is a vertical rack bar 14 the teeth of which are indicated by the numeral 15, it being understood that the rack bar is guided between the said edges of the flanges and also between the bolts 8 and that it has a free vertical movement. Loosely suspended from the lower end of the rack bar is a grappling hook 16 the use of which is obvious. In order to hold the rack bar at various adjustments I have provided a pawl which is pivoted to a pin 17 which connects the spaced arched frame members, this pawl being indicated by the numeral 18 and having its upper end en aged with the teeth of the rack bar interchangeably. The pan l is held in such engagement by means of a spring 20 which is connected at one of its ends to the upper end of one of the standards or supports 10 and at its other end to one end of a plate 21 which is secured to the pawl and extends transversely thereof, the other end of the plate being bent as at 22 to form a finger piece which may be grasped for the purpose of disengaging the pawl from the teeth of the rack bar.

In connection with the rack bar I provide means whereby it may be vertically moved and this means will now be described. A pair of links are pivotally suspended from the pin 17 and between these links at their lower ends there is pivoted a lever 24 the end of the lever beyond its pivot being bifurcated as at 25 for the reception of the rack bar 14, there being a pin 26 engaged through this end of the lever and across the bifurcation so that when the lever is engaged with the rack bar the teeth of the rack bar will engage over the pin so that vertical oscillation of the lever and at the same time successive engagement of the pin with the teeth, will result in a ver tical aching movement of the rack bar.

What is claimed, is: gageable with the rack bar to actuate the A lifting jack comprising a supporting same. 10 frame consisting of spaced members, a rack In testimony whereof, I affix my signabar shdabiy mounted therebetween, a pin I ture, in presence of two Witnesses. 5 extending between the members, a pawl piv- WILLIAM R. JOHNSON.

oted on said pin and engageable with the Witnesses: rack bar, links pivoted on said pin, and an ARTHUR A. GAINEs operating lever carried by said links and en- FRED TURNER.