USRE2117E - Improvement in sawing-machines - Google Patents

Description

PATENT OFFICE.

F. W. ROBINSON, OF RICHMOND, INDIANA.

IMPROVEMENT IN SAWlNG-MACHINES- Specification forming part of Letters Patent No. 49,791, dated September 5, 1865; Reissue No. 2,1 l 7, dated November 28, 1865.

TocoZZ whom t may concern:

Be it known that I, F. W. ROBINSON, of the city ot' Itichmond, and State of Indiana, have invented certain new and useful Improvements in DragSaws; and I do hereby declare the following to be afull, clear, and exact description of the same, which will enable others skilled in the art to make and use the saine, reference being had to the accompanying drawings, forming a part of this specification.

This invention relates to that class of dragsaws used for cross cutting timber, and is designed to produce a simple and durable machine coinposed of few parts and operating with little friction.

Figure l is a side view of my invention. Fig. 2 is a horizontal section of the same taken in the line x no, Fig. 1.

Similar letters of reference indicate like parts.

A represents a bar, which rests upon transvcrsebars G and forms the base of the framing of the machine.

D is a driving shaft, having upon it a crankpulley, E, to which a pitman, F, is attached. This pitman is connected with the saw-bar G at the butt or heel of the saw G', as shown at a.

G is a saw-bar, working between guides b I), which are attached to the bar A, and the saw has a guide, H, resting on its back or upper edge, said guide bring tltted in a groovevin a ratchet-bar, I, attached to the bar A or base of the machine. The saw-bar G is provided with a slot or opening in its back end of a length equal to the throw ofthe saw, and may be constructed either straight, or may be inclined downward, as shown in the drawings, said slot working upon africtionroller, Il', on an upright attached to the base. To the front end of the saw-bar G the saw G is rigidly attached. The sawbar G and the saw G', reciprocating together, are held in position by the friction-roller II at the rear end, and the guides b b at the front end of' bar G. The operation of the pitman F not only gives the reciprocating motion to the saw-bar and saw,

but from its position gives a vertical pressure y bearing for the rear end of the saw-bar almost without friction. The rear end ofthe saw-bar may be arranged with inclined slides, or may terminate in a rod working in a suitable opening, or any similar or analogous device may be used to provide the proper guides and bearings at that point.

Any of the ordinary devices may be used in connection with my invention for carrying the logs to the saw, and also for raising the saw during this process.

It will be observed that during the operation of sawing the saw and saw-bar have only two bearings, the one upon the log to be sawed and the other upon the roller H, placed at or near the driving-shaft, thus producingapressure upon the saw while cutting, and at the same time generating a reciprocal motion of the saw with great simplicity.

When the bent saw bar, as shown in the drawings, is used, or by the use of dipped or inclined slides at the rear end of the sawbar, a rocking motion will be given to the saw, which in large logs facilitates the clearing of saw-d ust from the kerf, thus avoiding friction.

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

A drag-saw in which the saw is rigidly attached to the saw-bar when said saw-bar isr provided with a slot at its rear end working upon or in guides situated at or near the drivin gshaft.

F. W. ROBINSON. Witnesses WM. T. DENNIS, FRANK DENNIS.

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