James F Strickland

US Patent:

39927792, Nov 23, 1976

Filed:

May 19, 1975

Appl. No.:

5/578414

Inventors:

Michael R. Marks - Shelton CT
James P. Strickland - Bourbonnais IL

Assignee:

Textron, Inc. - Providence RI

International Classification:

B23D 5702
B27B 1700
F16D 4904

US Classification:

30381

Abstract:

A brake for quickly stopping the cutting chain of a chain saw in the event of a kickback or other mishap comprises a narrow band of spring steel which wraps at least 11/4 turns around the drum of the centrifugal clutch by which the chain is driven. One end of the band is anchored while the other end is connected to an operating lever which is rotatable between a released position in which the brake band is released from the drum and an applied position in which the brake band is applied to the drum. The operating lever has a peripheral portion which has an interfering engagement with a cooperating portion on a rotatable actuating lever to which a guard or other sensing member is connected. By reason of this interfering engagement the operating lever remains in one or the other of its positions until forcibly moved to the other position by the guard member operating through the actuating lever. The mechanism can thus be set with the operating lever in released position and tripped by force applied to the guard member to rotate the actuating lever and thereby actuate the operating lever to bring the brake band into engagement with the drum.