Patent GB-725917-A (GB)
Title: Improvements relating to machines for hardening peripheral surfaces of circular bodies, such as wheels, cams and the like
IPC: C21D1/08
Filed: 1953-09-28
Abstract: 725,917. Hardening metals. PEDDING- HAUS, P. C., and PEDDINGHAUS, W., [trading as PEDDINGHAUS, P. F. [Firm of]]. Sept. 28, 1953 [Oct. 15, 1952], No. 26622/53. Class 72. A machine for hardening the peripheral surfaces of wheels, cams, &c., 1 in which the periphery of the rotating work 1 to be hardened is heated by preheating burner V and hardening burner H and is then quenched by a spray B is characterized in that cams 6, 7, 8 for the control of the preheating and hardening burners and the spray, and also of the drive of the machine, are arranged on a camshaft 5, which is connected by gearing 3, 4 to the main shaft 2 carrying the work, the transmission ratio of said gearing being such that the camshaft makes exactly a complete revolution during a complete operation of the machine, said camshaft being driven with a speed of rotation relative to that of the work such that, during the time a point on the periphery of the work rotates through 360 degrees plus the distance of the spray nozzle from the preheating burner, the said camshaft makes, at most, a complete revolution. The mode of operation is as follows. After fitting the work 1 on the main shaft 2, current is supplied to the magnet coil 34 by actuating pressbutton switch 35, whereby switch 33 is connected in circuit. Driving motor 27 thus rotates the main shaft 2 through gearing 28-31 and the shaft 5 is also rotated by the toothed wheels 3, 4, and thus cam 8 closes switch 26. Hence magnet coil 34 of switch 33 remains energized, so that the motor 27 continues to run after switch 35 is released. When switch 26 responds, water valve 36 is connected, and water supply to quenching nozzle B is opened; simultaneously, cam 6 closes switch 24, so that electromagnetic valves 40, 41 are energized and the burner V is fed with gas and oxygen, this mixture being ignited by a pilot flame, so that the burner V heats the periphery of the work. After due rotation, the part of the work heated by burner V arrives under burner H and'spray B. Simultaneously, cam 7 has turned through an angle #, so that switch 25 is closed by roller 10 thus actuating electromagnetic valves 42, 43 which open the gas and oxygen supply for burner H. The preheated part of the work is thus brought to the hardening temperature and is then quenched by spray B. On further rotation, the first hardened part finally arrives at the burner V. Simultaneously, cam 6 has rotated so that the roller 9 falls into its disconnecting position opening switch 24 and deenergizing valves 40, 41 thus putting burner V out of action. On still further rotation, the first hardened part arrives at burner H when roller 10 falls into the recessed portion of cam 7, opening switch 25, disconnecting electromagnetic valves 42, 43 and thus burner H. When the work has moved further forward by the distance of the burner H from the spray B, the roller 11 drops into the recess in cam 8, opening switch 26, disconnecting magnet coils 34, 36 thereby opening switch 33 and thus stopping the motor 27 and also stopping the water supply to spray B.