GB745985A - Improvements in and relating to log cutting saws - Google Patents

Abstract

745,985. Control of motors. ETABLISSEMENT GUILLIET COMMERGNAT-GUILLIET ET CIE. Feb. 15, 1954 [Nov. 4, 1953], No. 4432/54. Class 38(3) [Also in Group XXIII] A device for controlling the transverse feed of the log-holding claws of a saw comprises a rotatable arm 27 which is set according to the amount of feed required and, when the feed motor 13 is started, the arm is connected to a disc 18 rotated by the motor and is moved in 'the direction of the arrow F until it operates a motor stop switch 35 mounted on a stationary bridge 19. The arm, which is rotatably mounted on an extension 26- of a shaft 17, is loaded by a spring 28 to bear against a handle 25 on an annular scale 23 marked in millimetres and is set by rotating the scale until the required feed distance is indicated on the scale by a pointer 24, the scale then being clamped by a screw 31. The motor start switch 44 is operated by pressing in a lever 41 which at its other end. raises a collar 39 on the extension 26 so that a collar 38 on a resilient lever 37 is also raised to pivot the lever about an axis 36 and engage a screw 47 (not shown) on a downward extension of the lever with the disc 18, which is fixed on the shaft 17, thus. connecting the arm 27 to the disc; a spring-loaded latch 48 slides under the lever 37 and maintains it in the raised position. The shaft 17 is connected by gearing 16 and by a pair of selsyn synchronous motors 11, 12 to the feed motor so as to rotate proportionally to the feed motor and it carries the arm 27 with it until the arm operates the switch 35 to stop the motor and the latch 48 is disengaged by a stop 52, thus releasing the arm so that it returns under the action of the spring 28 until it meets the handle 25. The disc has graduations, which are distributed over three circles and correspond to centimetres of transverse feed and, as it does not return with the' arm 27, it integrates . the feed movements in cooperation with a pointer 22. The feed 'motor is provided with an electromagnetic brake 14 and its push switch 44 may be operated independently of the control device bv a lever 45. The levers 37 and 41 may have return springs and to increase the resiliency afforded by the lever 37, a spring may be fitted to the screw 47 (not shown) that engages the disc 18.