US2593596A - Circular saw guard - Google Patents

Description

April 22, 1952 G. v. oLsoN 2,593,596

CIRCULAR SAW GUARD Filed March 24, 1949 2 sxm'rs-SHEET 1 .INI/ENTOR. GEORGE V. OLSON April 22, 1952 G. v. oLsoN 2,593,596

CIRCULAR SAW GUARD l Filed March 24, 1949 2 SHEETS- SHEET 2' INI/ENTOR. GEORGE GLSON Patented Apr. 22, 1952 f UNITED STATES PATENT OFFICE 1 Claim.

My invention relates to improvements in saw guards and more particularly to improvements in guards applicable to circular saws.

The object of my invention is to provide a saw guard that is designed to eliminate congestion.

Another object of my invention is to provide a device that is equipped with an adjustable spreader or. splitter that acts as a guide and stabilizer for the guard.

Still another object of my invention is to provide a device that incorporates rigidity, eliminates whipping, and provides visibility while in use.

A further object of my invention is to provide a device that will accommodate various thicknesses of board and is provided with a pair of anti-backlash cams supported on both sides of the saw guard and arranged in a manner whereby they may be retained in an inoperative position.

A still further object of my invention is to provide a guard that is suspended in a manner that eliminates practically all of the backward movement of the guard before raising. l

It will be manifest to anyone familiar with th art that my device as described, incorporates all the desirable features enumerated above, may be constructed economically and yet be eicient for the purpose for which it is intended.

Other and further objects of my invention will become more apparent as the description proceeds when taken in conjunction with the drawing in which:

Figure 1 is a side View of the assembled device having its one side cover removed, and showing the device attached to a conventional saw table, the guard being in a down position.

Figure 2 is a similar view as shown in Figure 1, but showing the guard in a raised or upward position.

Figure 3 is a fragmentary top view of the assembled device.

Figure 4 is a side View of the assembled device.

Figure 5 is a bottom view of the device as shown in Figure 4.

Figure 6 is a fragmentary cross-sectional view taken at the line 6 6 in Figure 2.

Figure 7 is a fragmentary cross-sectional view taken at the line 'I--T in Figure 1, and

Figure 8 is an enlarged view of one of the antibacklash cams attached to the sideA plate of the device.

Similar characters of reference indicate corresponding parts throughout the several views and referring now to the same, there is a guard body consisting of a top plate Ill and two vvertical side plates Il and II forming an enclosure, open at its lower face and closed at the top. The side plates to the enclosure are provided with elongated apertures I2 which act as ventilators, and the side plates II and II are held in parallel spaced relation to one another by means of spacers I3 disposed over pins I4 fastened 'tothe side plates.

(Cl. 14S- 159) There is a spreader or splitter I5 at the rearward end of the guard assembly. This splitter or spreader is constructed of a good grade of steel, is wide and thin in cross section and is provided with open slots I6 at its lower edge to allow its vertical adjustment when supported by the bolt I6 engaging the table structure shown as I1.

This table I'I is equipped with a slot shown as I8 to accommodate a circulator saw blade I 9 which is shown in phantom, which saw blade is mounted to an arbor 20 in a conventional manner.

The spreader I5 is angularly disposed and is equipped with a pair of horizontal members shown as 2I which are attached to the upper end of the spreader I5 by means of bolts shown as 22. There are oil-set link members shown in two pairs, 23 and 23'; these members are pivotally attached at 24 to the member 2l at their upper ends, and at 25 to the side plates II and II at their lower ends. The links 23 and 23 are of the same length and are shown angularly disposed with their lower ends in a rearward position when the guard assembly rests on the surface of the table I1 as shown in Figure l. This feature reduces, to a minimum, the rearward movement of the guard as the work piece is inserted under the guard, against the front guide which is shown as 26 and which is angularly disposed at its flatforward end. It is shown cast integral and is attached to the side plates II and II' by means of screws 21. The guide member 26 is provided with an elongated opening 28 at its top which provides visibility and enables the operator to observe the engagement of the teeth of the saw I9 with the work piece when the cut is started.

Obviously the top plate I6 encloses the top only and is provided with an open portion 29 to allow for the engagement of the member 26 at the forward end of the guard assembly. Y

The swivel mounting of the link members 23 to the side plates II and II is shown in detail in Figure 6. It will be noted that there are pins 36 having inwardly disposed members 3| of a diameter greater than the pins 30. The pins 30 are disposed within the link members23, the pins acting as a bearing for the pivoted mounting of the link members 23. The spacer Washer 32 separates the member 23 from the inside face of the side plates II and II and the .pinsare journaled in bearings shown as 33 which bearings are mounted within the `side gplates. Thel entire assembly is held in position by means of lock rings 34 engaging-a-semi-oircular groove 35 encircling the outer periphery oi? the pins 3G. The faces 36 of the enlarged members 3| contact the surface of the splitter or spreader l5 on both sides thereof, thereby providingstabilization and .rigid itytothguard assenrlblyfY f In Figure 7 I show a cross section of a pivot support indicated at the line 1 1 in Figure 1. There is a pin 31 supported by the horizontal members 2| attached to the spreader I5. This pin 31 is equipped with a cylindrical spacer shown as 38 disposed between the members 2|, and the link members 23' are pivotally mounted to the pin 31 on the outside of the members 2| and the spacer washer 39 engages the outer periphery of the pin 31 at its extreme ends between the members 23 and the inside face of the plate and Obviously the same constructionis employed to support the upper end of the link members 23 disposed near the rearward end of the guard assembly.

The extreme rear end of the plates and il are angularly disposed at 40 and the spacer I3 over the pin -|4 at 4| limit the downward movement of the guard, the angle 40 permitting the gradual descent of the guard assembly as the Work piece is passed through. The lower edge of the plates and are provided with inwardly disposed angular members 42 constructed integrally with the plates, and these angular members are cut out at 43 to permit a pair of anti-backlash cams shown as 44 to extend downward through the cutout portion 43 thereby causing the teeth 45 on both of the cams 44 to contact the upper surface of the work piece being fabricated. The cams 44 are rotatably mounted to the pins 25' extending through the plates Il and which act as a support for the bottom of the links 23'. The rearward end of the cams 44 have a `screw which is shown as 46 threadedly inserted therein, and the platesv and Il' have an aperture 41 of a diameter larger than the head of the screw 45 which guide and limit the movement of the cam 44 for its engagement and disengagement of the teeth-45 with the upper surface of the work piece.

Inasmuch as the cams 44 are mounted to each side wall of the guard, it will become manifest that equal support is provided on both sides of the saw while the cams are in contact and in engagement with the work in process. Y

In Figure 8 of the drawing, is shown an enlarged view of the cam construction illustrating the manner in which the pins 25 `are retained in position by means of a spring collar shown as 48 engaging semi-circular grooves on the outer periphery of the pins 25. If desirable, the cams may be retained in an inoperative position vby use of a conventional washer over the pin 25.

From the above description, it will become apparent that the unit as described incorporates a sturdy guard that is ventilated by means of the slots, and Vis slideably sup-ported against side movement by the engagement with the side walls of, the spreader. Four lifting links of equal length and langulariy disposed, control the objectionable backward movement when the work piece is inserted and provide a maximum lifting range of the entire assembled guard. The inclined rearward end of the guard permits the gradual downward movement when the work piece is passed through under the guard. The guard assembly is shown employing collars or snap rings to overcome the objectionable nut and bolt `arrangement which is commonly used for this type of purpose.

-The cast forward end permits a gradual feed of the work piece and provides visibility. rPhe fiat angular engaging surface at the front provides ease of inserting the work piece thereby gradually raising the guard while the device is in use, and a double arrangement of the backlash cams provides safety and security in feeding the work piece while the wide spreader to which the entire guard is attached, eliminates any whipping action or side play.

While I have shown a specic arrangement of the component parts constituting the device, I am fully cognizant of the fact that many changes may be made in their form and contour without affecting their operativeness and I reserve the right to make such changes as I may deem advisable or convenient without departing from the spirit of my invention or the scope of the appended claims.

Having thus described my invention, what I claim and desire to secure by Letters Patent of the United States is:

A guard of the character described to be used in combination with a circular saw and table, said guard consisting of an enclosure constructed of a top plate and a pair of vertically disposed spaced parallel side plates, pins extending between saidl plates and secured thereto, a spacer mounted on each of said pins and interposed between said plates, said side plates being each provided with a plurality of elongated apertures, a splitter blade, means for adjustably mounting said splitter blade to said saw table, said blade having open slots in its lower edge constructed of a vwide plate of substantially thin cross section extending longitudinally with said enclosure, a support member horizontally disposed and having a portion entirely enclosed within said guard, extending forward from said blade and attached to the upper end thereof, a plurality of link members of equal length oppositely disposed from one another, said link members pivotally attached at their upper end to said horizontal support member and at their lower end to the inner face of the vertical side plates forming said enclosure, said enclosure encasing a portion of said splitter head and horizontal member, and provided with a spacer member rearward from said splitter blade to arrest the travel of said enclosure in its downward path, thereby retaining said link members in an angular position, inwardly extending members supported at the lower end of a pair of said link members for slideable contact with both sides of said splitter :blade members extending inwardly from sai-d guard to said splitter blade throughout the movementof said guard to and from the table, a pair of anti-backlash cams rotatably mounted to said vertical side plates on the lower en-d thereof, said cams equipped with serrations on the lower face thereof, means on said side plates for limiting the upward movement of said cams, said side plates provided with an angularly disposed rear edge extending upward from their bottom edge and an engaging member attached to the forward end of said vertical plates between said plates, said engaging member provided with an angularly disposed contact surface at its front and an aperture through its top.

GEORGE V. GLSON.

REFERENCES @FEED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 299,480 Kuhlmann May 27, 1884i 1,255,385 Jones Feb. 12, 1918 1,496,212 French June 3, 1924 "2,425,331 Kramer Aug. 12, 194?

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