US1572856A - Tree jack - Google Patents

Description

Feb. 9 1926.

L. WATSON ET AL TREE JACK Filed July 21, 1925 lNl/KNTOBS L MIME/7E6 VVdlffQ/Z AIL/51777 Q M/dd/fiW/JJ ATTORNfY Patented Feb. 9, 1926.

UNITED STATES PATENT OFFICE.

TREE JACK.

Application filed July 21, 1925. Serial No. 45,027.

To all whom it may concern:

Be it known that'we, LAWRENCE Mason and AUSTIN O. MIDDLEMISS, citizens of the United States,residing in Vancouver,county of Clarke, and State of Washington, have invented a new and useful Tree Jack; and we do hereby declare that the following is a full, clear, and exact specification, such as will enable others skilled in the art to which it appertains to make and use the same. i

The invention is a jack that is particularly adaptable for falling trees or the like.

The object of the invention is to provide a small sturdy jack with a swivel head that may be placed in a small uneven space and that will exert a great pressure for a short distance.

Another object of the invention is to provide a small sturdy jack which is of a light weight and at the same time durable.

And a further object of the invention is to provide a small sturdy jack of a simple and economical construction.

\Vith these ends in view, the invention embodies a cylindrically shaped base with threads on its outer surface, a cylindrically shaped cap with a curved top and threads on its inner surface, and a head slidably held in an opening in the center of the ca 3.

Other features and advantages of the in vention will appear from the following description, taken in connection with the drawings, wherein Figure 1 is a vertical section through the 'ack.

1 Figure 2 is a View looking toward the lower side of the cap.

In the drawings, we have shown our device as it would be made wherein numeral 1 indicates the base, numeral 2, the cap and numeral 3 the head.

The base 1 may be cylindrically shaped as shown with the upper end open and the lower end closed, teeth at on the bottom and threads 5 in its outer surface. 7

The cap 2 is also cylindrically shaped with its lower end open and its upper end provided with a curved surface 6 having an opening 7 in the center, its inner surface provided with threads 8 to correspond with threads 5 of the base and its outer surface provided with lugs 9 by which it inlay be gripped by a spanner wrench or the li (e.

The head 3 is made of a solid circular piece of material with its under surface 10 curved to correspond with the upper surface of the section 6 and its upper surface provided with projections or teeth 11 similar to the teeth 4. In the center of the under side of the head 3 is a bolt 12 with its outer end threaded and provided with a nut 13 for holding a washer 14: against the inner surface of the section 6. It will be observed that by turning the nut 13, the friction between the washer and the under side of the section 6 may be adjusted.

It will be understood that changes may be made in the construction without depart ing from the spirit of the invention. One of which changes may be in the design of either of the'members, another may be in the use of other means for rotating the cap, and still another may be in the use of'other means for attaching the head to the cap.

The construction will be readily understood from the foregoing description. To use the device, the cap may be screwed down upon the base and when used for logging and particularly for falling and bucking timber, it will. be placed in a notch in a saw cut and it will be observed that as the cap is unscrewed or turned so that it will move upward, it will exert a tremendous pressure thereby eliminating wedges or the like. Although this device is particularly designed for this use, it is understood that it may be used for any similar work or for any other purpose.

Having thus fully described the invention, what I claim as new and desire to secure by Letters Patent, is

In a lifting jack, a cylindrically shaped base with threads on the outer surface, a cylindrically shaped cap with threads 011 the inner surface to correspond with the threads of the base, and means on the outer surface of the cap by which it may be rotated, said cap having a curved upper surface with an opening in the center and a head with a stem projecting through the opening of the cap, said stem having means at its inner end for adjustably and slidably holding the head to the cap.

LAWRENCE WATSON. AUSTIN O. MIDDLEMISS.

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