Improvements in electrically operated temperature regulating mechanisms

摘要

437,002. Thermostats. VAPOR CAR HEATING CO., Inc., 80, East Jackson Boulevard, Chicago, U.S.A. Feb. 4, 1935, No. 3572. Convention date, Feb. 26, 1934. [Class 64 (ii)] An arrangement for automatically controlling the temperature of air supplied from a fan C to a chamber through a duct B comprises a heater D, a cooler E and a selector switch K by means of which the heater or the cooler may be put in operation, the switch also having contacts to enable one of a number of predetermined temperature settings of the control apparatus to be selected. The temperature is thermostatically controlled by means of thermostats 47, 82, 84, 111, 117, 118, a separate thermostat being provided for each temperature setting. The switch has a central neutral position and anticlockwise movement from this position causes energization of the heater and selection of the appropriate thermostat associated therewith. Similarly clockwise movement causes energization of the cooler which is supplied from a refrigerator G. Linked with the switch K by a lever 41 is a snap action switch LL<1> which snaps over when the neutral position of the switch K is passed to connect the relay P to control the fan motor when the switch K is on the heater contacts, and to connect the relay P to control the refrigerator motor 10 when the switch K is on the cooler contacts. When the switch K is on a heater contact, e.g. as shown, the contacts of the thermostat 47 are connected across the winding 52 of a relay N energized through the bridging contact 13 of the switch K. Closure of the thermostat-contacts short circuits the relay winding 52 which operates to cause the valve 5 on the steam supply to be shut by the energization of a solenoid 67. Movement of the valve lever trips a switch 71 which opens the circuit of solenoid 67 and resets the circuit of solenoid 79 for reverse action when the thermostat contacts open due to fall of temperature. The speed of the fan motor C is controlled by a thermostat M through relays O and P, when the temperature rises the fan speed is increased by a resistance 87 being short circuited. When the switch K is on a cooler contact, e.g. contact 25, the thermostat 111 is placed in series with the winding of relay O and the relay P is connected by the switch L, L<1> to the motor 10. When the thermostat contacts close due to a rise of temperature the relays O and P operate to close the circuit of the motor 10 and start the refrigerator G. When the temperature drops the relays O, P open to stop the motor. An additional contact 27 is provided for running the refrigerator constantly independent of temperature variations.