GB578622A - Improvements in or relating to brake devices for power transmission mechanism - Google Patents

Abstract

578,622. Loading ordnance. HARVEY, V. P., MASON, J. A., and MOLINS MACHINE CO., Ltd. July 16, 1942, No. 9907. [Class 92 (i)] [Also in Group XXXIV] To bring a driven device to rest when the power is cut off from the driving device, the tendency of the driven device to overdrive the driving device is utilized to apply a brake. The braking device is described as applied to a gun-loading tray 1 which is arranged to be oscillated about a pivot 2 between the two positions shown, the broken-line position being that in which the shell 3 is in alignment with the breech of the gun. The tray is driven by a motor 10 through a crank 5 on a wheel 7 geared to a worm 8 splined at 18 to the motor shaft so as to be axially movable and carrying a friction disc 11 for engagement with a non-rotatable disc 12 pressed by a spring 16 adjustable by a nut 14. The motor may be controlled by a hand-switch 21 or automatically as described in Specification 578;621. When the motor is driving the tray, the axial thrust of the worm is taken, by a bearing 19, but when, prior to the tray reaching either of its end positions, the circuit is broken, the tendency of the wheel 7 to drive the worm effects axial displacement of the worm and compression of the spring 16 to an extent determined by clearance provided at a second thrust-bearing 20, the friction discs 11, 12 being engaged with a corresponding pressure. The axial movement of the arm may instead apply brake blocks to an external surface of the worm through linkage. According to the Provisional Specification, spiral, rack, bevel or ordinary spur gearing may be used instead of worm gearing, the axial thrust or the slight relative movement between two gears due to reversal of the direction of the tooth pressure being used to actuate a brake.