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Publication numberUS545504 A
Publication typeGrant
Publication dateSep 3, 1895
Filing dateApr 29, 1895
Publication numberUS 545504 A, US 545504A, US-A-545504, US545504 A, US545504A
InventorsFrancis M. Hoover
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
US 545504 A
Abstract  available in
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

(No Model.)



No. 545,504. Patented Sept. 3,1895.

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est .l

A tion of a circular saw projecting above a work- UNITED STATES PATENT OEEICE.



SPECIFICATION forming part of Letters Patent No. 545,504, dated September 8, 1 895. Application led April 29,'1395- Serial No. 547,510 (No model.)

To all whom it may concern:

Be it known that I, FRANCIS M. HOOVER, a citizen of the United States, residing at Brookville, in the county of Franklin andwState of Indiana, have invented certain new and useful Improvements in Saw-Guards; and I do hereby declare the following to be a full, clear, and exact description of the invention, reference being had to the annexed drawings, which form a part of this specification.

My invention comprises a guard which is so constructed as to -inclose the segmental porbench or table within which it is journaled, the device being capable of performing the fourfold duties of a fender that prevents the operators fingers being caught by the saw, of a screen that prevents him `being injured by flying splinters, of a clamp that holds the stuff down on the table with a yielding pressure, and of a protector that prevents the saw being injured by anything falling upon it, as hereinafter more fully described.

In the annexed drawings, Figure lis a front side elevation 0f my improved guard attached to a table or bench, the latter being sectioned, and the segmental portion of a circular saw indicated with dotted lines. Fig. 2 is an elevation of the rear side of the guard, the table and its saw beingomitted. Fig. 3 is a plan of said guard. Fig. 4 is a side elevation of the kerf-plate and its accessories. Fig. 5 is a vertical section of said plate, taken at the line z z of Fig. 2. Fig. 6 is a plan of a dovetail clamp, wherewith this kerf-plate is coupled to a bed-plate of the guard. Fig. 7 is'a section through a spring that assists in imparting a yielding pressure to a pair of side plates of the guard. Fig. 8 is a vertical section of a portion of the korf-plate, taken in the plane of a pair of integral guides of said presser-plates.

Of the above illustrations, Figs. 5, 6, and 7 are drawn on an enlarged scale.

The attaching member of my guard is a fiat bed-plate A, having transverse slots c a near its ends to admit countersunk heads of screws or bolts, wherewith said plate is adjustably .secured upon a bench or table B. In addition to these slots the bed-plate has a pair of circular pits c a', that receive thumb-nuts C C', engaged with the upper ends of screws c c', connecting a parallel clamp-plate D to said bed-plate A. This clamp-plate is located below the bedplate, the two members A D serving to hold a flange e, projecting horizontally from one side of a vertical dovetail plate E, and near the top of the same. Plate E is wider at bottom than at top, as seen in Fig. 2, and its edges are flared, as represented in Fig. 6, to fit snugly within a pair of undercut guides f f of the kerf-plate F. This plate is a thin rigid piece of metal of the same width as an ordinary circular saw, one edge of said plate being notched at G and its opposite edge being notched at H. Furthermore, the upper edge ot' said plate has a vertical slot I, that communicates at bottom with a rearward extension 12, as more clearly seen in Fig. 4. Adapted for ready attachment to this kerfplate is a springfbar .Ithe straight upper portion of which has a longitudinal slot j just wide enough to clear said plate and terminating at rear with a cross-piecej of such a size as to be passed down through the slot I, and then engage with its extension i. Again, said spring-bar has a notch j on one side to admit a hook or other keeper K, attached to the kerf-plate, one end of said spring being bent or'inclined upwardly at J to facilitate the insertion of stuff under said guard.

LL are parallel presser-plates pivoted to the spring-bar at ZZ and united at the opposite end by a cross-piece L, these three members L L L being usually made of a single piece of sheet metal.

M is a loop or shackle applied to the presservplates and adapted to engage with either one of the notches H of the kerf-plate, as seen in Fig. 4. The presser-plates are slotted verticallyr at N N and then-bent inwardly, thus forming horizontal guides. n n', that bear against the opposite sidesof the kerf-plate F and con tine said plates L LA to a vertical path when they are moved up and down. (See Fig. 8.) Fitted within these presser-plates is a bent spring O, the central portion of which constantly bears against the under side of the spring-bar J, as more clearlyjseen in Fig. 7, the opposite ends of said spring being bent outwardly at o o and then passed through said plates. j


P P are pins inserted in these plates in such a manner as to cause the spring O to force them down with considerable pressure.

The dotted lines S S S, in Fig. 1, represent the upper portion of a circular saw that occupies a slot b in the bench or table B, to which latter my guard is applied, as follows:

The bed-plate A is yrst let into a mortise, so as to be flush with the upper surface of the table, as seen in Fig. 1, in order that there may be no obstruction oiered to the stuff to be sawed, the plate being properly adjusted by fasteners that traverse the slots a a and the fitting being rendered still more accurate by shifting the flange e between the two clamping devices A D. The object of these various adjustments is to locate the kerf-plate F accurately in line with the saw, so as to prevent anypossible binding,andafterthis precaution has been attended to the nuts c c are tightened, thereby holding the flange e and dovetail plate E immovably in place. N ow as the kerf-plate F is coupled to this dovetail piece E by the guides f f', it is evident said plate is retained against lateral play, but is free to slide up in the event of an accident, and then to drop down as far as these connec tions Eff will permit, the normal position of said connections being seen in Fig. 2.

In coupling the spring-bar J to the kerfplate the hook or other fastening K is iirst thrown back and the longitudinal slot j of said bar is passed down over said plate F in such a manner as to cause the cross-piecej of the bar to traverse the vertical slot I of said plate. The spring-bar is next shifted rearwardly, thereby causing this cross-piece j to enter the rear extension t' of said slot, while at the saine time the front end ot' slot j engages with either one of the notches G, according to the tension to be imparted to said spring J. I-Iook K is now engaged with the notch j, so as to prevent longitudinal shifting of said bar in either direction and thereby preserving it at the desired stiffness or tension. This tension is suiiicient to hold the bar down on the table B with some degree of force, and the parallel presserplates L L are also forced down. by the other spring O. Such being the normal positions of 'all the operative parts of the-guard, it is evident an entrance 'l is attorded between the table B and inclined end J of the spring-bar, and when the stuff is fed in at this entrance said spring is gradually raised. As the stuff is advanced, the presser-plates L L are also raised, and by the time the board or other piece has reached the saw said piece is held in place by the combined action of the two springs J and O. As soon, however, as the stuff is severed, the springJ is the tirst to swing down on thetable, and when the piece has passed completely through the machine the presser-plates L L again resume their normal positions, and these automatic actions will take place, no matter how thick or thin the lumber may be. Again, owing to the peculiar arrangement of the springs .I and O, their combined pressure will be uniform on any thickness of stud.

From the above description, in connection with the annexed drawings, it is evident the curved portion of spring .I acts as a guard over the saw, while the presser-plates L L serve as fenders at the sides thereof. Consequently it is impossible for a persons finger to accidentally come' in contact with the segment of the saw projecting above the table B; but when it is desired to inspect any of the saw-teeth it can be done after swinging up the free end of the presser-plates L L and engaging their shackle M with one of the notches I-l, as seen in Fig. et.

I claim as my invention- 1. A spring-bar applied to a kerf-plate, and having side presser-plates pivoted to it, which plates are provided with an independent spring.

2. A saw-guard including a bed-plate; a v

clamp-plate connected thereto; a dovetailplate having a lateral-Harige inserted between said plates; a kerf-plate having guides that admit said dovetail-plate; and a spring-bar applied to said korf-plate.

3. The combination, in a saw-gnard, of a kerf-plate; a spring-bar applied thereto; and a pair of spring-actuated side-plates L, L', pivoted to said bar, said plates being provided `with inwardly-bent integral-guides n, n', that bear against the opposite sides of said herfplate, in the manner described, and for the purpose stated.

4. A saw-guard including a hert-plate; a spring-bar applied to it; side presser-plates pivoted to said bar; and a device for retaining the free ends of said plates in an elevated position.

5. A saw-guard including a spring-bar; a pair of side presser-plates pivoted thereto; and a spring O, having a central bend in contact with said' bar; its ends applied to said plates; and pins P, P', inserted in the latter', near the ends of said spring O.

6. A saw-guard including a kerf-plate having a slot I, provided with a lateral extension 11; a spring-bar J having a longitudinal slot j, cross-bar j', and notch j and a keeper K applied to said plate, and engaged with notch j.

7. The combination, in a saw-guard, of the slotted bed-plate A tt a; clamp-plate D, secured thereto; dovetail plate E, having a flange e, fitted between said plates A, D; kort'- plate F, having guidesjf, that engage with said plate, E a keeper K, applied to said plate F; alongitudinally-slotted spring-barJjjj, carried by said plate F and side presser-plates L, L', pivoted to said spring-bar, and retained in their normal positions by a spring 0.

In testimony whereof I affix my signature in presence of two witnesses.






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