US161583A - Improvement in jig-saws - Google Patents

Description

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N ,1 1,5 3 Patented March 30,1875.

THK GRAPHIC C0.PHOTO -L|TN.39&41 PARK PLAGE,N-Y.

GILES S. WILLIAMS, OF MADISON, WISOONSIIT.

IMPRQVEMENT IN JlG-SAWS.

Specification forming part of Letters Patent No. 161,583, dated March 30, 1875; application filed December 10, 1874.

To all whom it may concern:

Be it known that I, GILEs S. WILLIAMS, of Madison, in the county of Dane and State of Wisconsin, have invented certain new and useful Improvements in Jig-Saws; and I do hereby declare the following to be a full and exact description of the same, reference being had to the accompanying drawings, forming part of this specification, in which Figure 1 is a side elevation, partly in section, showing my improvements; and Fig. 2 is a front elevation of the same.

Similar letters of reference in the accompanying drawings denote the same parts.

My invention has for its object to improve the construction of jig-saws for the general purpose of rendering them more complete and efficient in their operation. To this end the invention consists, first, in vibrating the saw-frame by means of a compound double toggle-lever, connecting it directly with the operating-treadle. It also consists in connecting the compound double toggle-lever to the frame of the machine, by means of a vibrating pivot-arm, for the purpose of in creasing the reciprocations of the saw. It also consists in connecting the compound double togglelever with one or more balancewheels by means of a crank-shaft and connecting-rod, for the purpose of equalizing the movements of the saw.

In the accompanying drawings, A is the frame of the machine, made of the requisite height, and provided at its rear end with the upright B, and at its front end with the sawing-table G. D is the saw-frame, composed of the beams E E, pivoted or hung between the uprights, and connected at their rear ends by a strap or loop, F. G 1s the saw, passing through the table 0 in the usual manner, and connected to the forward ends of the saw-frame by the loops H I. The loop I fits over the end of the upper arm, so as to move up and down thereon, and is provided with a cam-lever, J bearing upon the top of the arm, by the operation of which the saw is strained or loosened. Between the loop F at the rear end of the saw-frame and the top of the upper beam a metal or rubber spring, K, is interposed to assist in preserving the tension of the saw, and to compensate for the wear of the locking-cam lever. L is an upright, pivoted in a foot-bar, M, at the front of the frame, and N is the treadle, mounted upon the pivot of the upright. 0 is a short bar or rod, pivoted at its upper end to the lower beam of the saw-frame beneath the saw and P is a longer intermediate bar, pivoted to the top of the upright and lower end of the bar 0, so as to connect the two, as shown in Fig. 1. Q is an arm, hinged at its inner end to a central cross-bar, R, of the frame, and pivoted at its outer end to the center of the bar P.

The several bars, together with the upright, form a compound lever, by the operation of which the saw-frame is vibrated, while the arm Q, holding the center of the bar P in position, causes it to oscillate upon a central pivot, and therefore increases the vibrations of the saw when the treadle is operated.

The inner end of the pivot-arm Q is necessarily hinged to the central cross-bar, because its outer end moves through a short are when the compound lever is in operation. Otherwise the connections must either give way, or the lever become immovable.

S is a pivoted rod, connecting the upper end of the upright with the crank of a crossshaft, T, arranged at the rear of the frame, and carrying two balance-wheels, U U.

When the compound lever is in operation the oscillations of the upright communicate motion to the balance-wheels through the medium of the connecting-rod and crank-shaft, for the purpose of steading the movements of" the compound lever, and therefore equalizing the strokes of the saw. Instead of employing two, one large balance-wheel may be used, if preferred.

By my invention the mechanism for operating jig-saws is greatly simplified and cheap- L ened, while the efficiency of the machine is increased by doubling the vibrations of the saw withirra given time, and rendering such vibrations steady and uniform.

Instead of applying the compound lever to a saw-frame it may be applied to various other devices where a vibrating or reciprocating motion is required without departing from the spirit of my invention, as will be readily understood.

Having thus described my invention, What I claim as new isit 1. The compound double toggle-lever connectin g the saw-frame of a jig-saw directly with the operating treadle, substantially as described, for the purpose specified.

2. The vibrating pivot-arm Q, connecting the compound lever to the frame of the machine, substantially as described, for the purpose specified.

3. The combination of the compound lever, vibrating pivot-arm Q, and the balance-Wheels with the saw and frame of the machine, substaantially as described, for the purpose specifie GILES S. WILLIAMS.

Witnesses OLIVER SWIFT, BENONI S. WILLIAMS.

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