GB445425A - Device for hardening metal surfaces - Google Patents

Abstract

445,425. Hardening metal surfaces. I. G. FARBENINDUSTRIE AKT. - GES., Frankfort-on-Main, Germany. Oct. 8, 1934, No. 28761. Convention date, Oct. 7, 1933. [Class 72] An apparatus for hardening metal surfaces by the application of a flame and a subsequent quenching, is provided with a pyrometer and switching devices so that when the desired temperature of the surface has been attained, the supply of gas is automatically shut off and the supply of the quenching agent applied. The rotating pivot 1 is heated by the nozzles 6 of a burner 2 provided with a chamber 5 which is fed with fuel gases by a conduit 4 from tubes a, b passing through a cock 3. Additional air for combustion is fed by a conduit 7 from a pipe c to a chamber 8 the air passing through passage 2. The burner may be provided with a cooling chamber 7 the cooling agent being fed thereto by pipes x<1>, x<2>. When the pivot 1 has been heated to the required temperature, a magnet 11 is energized through an amplifying device 10 by a pyrometer 9, and by the attraction of the core 12 a rack 13 moves a toothed segment 14 connected with the plug of the cock 3, thus shutting off the gas supply and quenching agent flows from a pipe 5 through the conduits 4, 7 to quench the pivot 1. A time release on the magnet is adjusted to operate at the end of the time set for the quenching and then a spring 15 draws the rack 13 into the position set by the pawl 16 engaging a stop 19 when the supply of both the gas and quenching agent is cut off. If workpieces are to be hardened in series the device is arranged so that when the quenching is finished, the rack is drawn back into its original positions in which the pawl engages the stop 18 the gas supply being then opened. The stop 19 is dispensed with or suitable means are provided to prevent the pawl 16 engaging the stop 18 until the operation is finished. The main flange is then lit by a pilot jet and the operation repeated.