GB483956A - Automatic bell-ringing device - Google Patents

Abstract

483,956. Bell - ringing mechanism. BOCHUD, L. Aug. 7, 1937, No. 21809. [Class 13] In an automatic bell-ringing device comprising an electric motor provided with a speed-reduction gear for transmitting the drive of the motor to the rotatable shaft of the bell and an automatic lever-reversing device for intermittently changing the direction of the electric current to effect periodic reversal of the direction of rotation of the motor, the lever-reversing device comprises operated members and associated operating members, some of the members being carried by an extension of the motor shaft, whilst others are mounted on the counter-shaft of the speed reduction gear. The bell is mounted on a shaft carrying a wheel connected by a chain to a wheel 13 fast on the counter-shaft 14 of a reducing gear 18, 18<1> driven from an electric motor 15. The operating circuit and direction of rotation of the motor are controlled by contacts 32, 32<1> and 33, 33<1> engaged by contacts 26, 26<1> carried on an arm 25 rotatably mounted on the counter-shaft 14. Mounted loose on the motor shaft are cam discs 19, 19<1> integral with a gear wheel 20 meshing with a wheel 21 on the shaft 14. The discs 19, 19<1> have ramps 22, 22<1> and 23, 231 respectively which engage with rollers 27, 27<1> carried by arms 24, 24<1> integral with the arm 25. The member 25 is actuated to its circuit closing position by a finger 28 frictionally coupled to the motor shaft by discs 29, 29<1> and a spring 8. The arm 25 is normally biassed by a spring 31 to close the contacts 32, 32<1> and during the initial motion of the bell the finger 28 moves to the right. The inertia of the bell overcomes the torque of the motor and reverses its swing causing the finger 28 to rotate in an anticlockwise direction and to move the arm 25 to close contacts 33, 33<1>. These movements continue until the bell reaches a predetermined amplitude denoted by alpha in Fig. 7 when ramp 22<1> on disc 19 engages the roller 27 on arm 24 and moves the arm 25 together with the finger 28 to a central position thus opening the motor circuit. When on the return swing the bell again reaches the position A, the arms 24, 24<1> are not restrained bv the ramps 22<1>, 23<1> and the finger 28 moves the switch-arm to close contacts 33, 33<1> completing the circuit for the reversed drive. When the bell reaches the position B on its upward swing. cam 23 on disc 19<1> engages roller 271 on arm 241 and cam 22 on disc 19 engages roller 27 to move the contact member to its central position, and to hold the circuit open until the bell reaches B on its downward swing. In a modification. Figs. 4, 5 (not shown), the arm 25 is formed with a loop engaging the countershaft 14 and is integrally formed with arms corresponding to the arms 24, 24<1> shown in Fig. 2, and is actuated to its contact-making positions by forked projections carried by a ring frictionally mounted in a recess in a wheel keyed to the shaft 14. The upper end of the arm 25 is biassed to one or other of its contactclosing positions by a spring and lever arrangement.