Feeler operated saw guard

• US 3,880,032 A
• Filed: 08/22/1973
• Issued: 04/29/1975
• Est. Priority Date: 08/22/1973
• Status: Expired due to Term

• Current Assignee: Dwight C. Green
• Original Assignee: Dwight C. Green
• Inventors: Green, Dwight C.
• Primary Examiner(s): Schran, Donald R.
• Application Number:
  US05/390,555
• Time in Patent Office: 615 Days
• Field of Search: 83/102.1,478,860,544
• US Class Current: 83/102.1
• CPC Class Codes: B27G 19/02 for circular saws
• CPC Class Codes: Y10T 83/2077 By kerf entering guide
• CPC Class Codes: Y10T 83/7734 With guard for tool
• CPC Class Codes: Y10T 83/872 With guard means
• CPC Class Codes: Y10T 83/96 Guard

Abstract

A pivoted finger feels the thickness of a board by rotating to the angular position that allows the board to pass under the feeler. The feeler finger rotates a cam that in turn actuates a mechanism to lift the saw guard by the dimension indicated by the angular position of the feeler. Thereupon the board or other work piece can be cut by the saw. The guard preferably does not rest on the work piece so that work feeding friction is at a minimum. The guard raising mechanism may be mechanical, hydraulic or electric, and the mechanism may be mounted on a splitter for saw blades that can be set at an angle to the saw table other than 90*. The mechanism may be mounted on an over-the-table arm for stationary saws or for radial arm saws in which latter case the guard and feeler move with the saw.

Claims

1. In combination with a saw table having a saw projecting through the table, a guard mechanism comprising:

a. a support disposed above the saw table;

b. a feeler pivoted to the support and having one free end normally disposed closely adjacent to the saw table to be contacted by a work piece having relative movement with respect to the saw;

c. a first non-linear cam rotated by the feeler as the feeler rotates in response to being contacted by a work piece;

d. a second non-linear cam and mounted for rotation on the support;

e. a flexible tension strap connecting the cams together so that tHey rotate in unison;

f. and a saw guard disposed over the saw and normally positioned over the saw and close to the saw table and mechanically engaging at least one of said tension strap and cams for movement toward and away from the saw table, whereby rotation of the feeler by a work piece causes the cams to rotate and lift the guard vertically a distance just sufficient to allow the work piece to pass under the guard and contact the saw.

2. The combination of claim 1 wherein the free end of the feeler finger has a pointed terminus to dig into work pieces and thus act as an anti-kickback.

3. The combination of claim 1 wherein the saw is moveable to different angles relative to the saw table, the guard mechanism is mounted on a splitter plate, and the table is provided with a splitter plate lifting and lowering mechanism so that the feeler and guard maintain the same clearance from the table, regardless of the angle of the saw to the table.