GB886632A - Electrically actuated rotary valve zone heating control system - Google Patents

Abstract

886,632. Automatic temperature control systems. DOANE, D. B. Oct. 9, 1958, No. 8355/59. Divided out of 886,631. Class 38 (4). [Also in Groups XXIX and XXXVII] A plurality of motor-actuated rotary valves 11, Fig. 1, each carrying a switching device and each controlled by a temperature-sensitive device, e.g. a thermostatic switch 93, Fig. 8, have an electric power source at 90 common to all the temperature-sensing devices, switching devices and valves and an electrically-operated heat-transfer medium flow producing device, e.g. the electric motor pump 107 passing heat transfer medium through the valves, which is electrically connected to the switching devices and electrical circuitry so arranged that any one of the switching devices brings the flowproducing device into operation. The rotary valve comprises a valve 11 controlling flow through the body 10, a base-plate 25 removably attached to the body and carrying a unidirectional electric motor 64 mounted on a terminal plate 43 and a rotary switch 55, and a motor shaft extending through the terminal plate and through and connected to the rotary switch into driving engagement with the stem 33 of the valve for unidirectional co-rotation of the switch and the valve. On heat demand thermostatic switch 93 connects with contact 92 and current flows from a transformer secondary coil at 90 via a conductor 80 continuously in contact with the rotor 72 of the switch, and via rotor arm 87 connecting contact 79 through the motor 89 which then begins to open the valve and turn rotor 72. When the valve is partially open rotor arm 87 engages contact 81 whereby current flows through a relay for operating a pump circulating heating medium through the valve. When the valve is fully open arm 87 leaves contact 79 and engages contact 82 and motor 89 stops. When the heat demand is satisfied switch 93 returns to contact 94 whereby current flows via contact 80, rotor 72, arm 87 engaging contact 82 so that motor 89 continues rotating in the same direction until arm 87 leaves contact 81 to stop the circulating pump and when the valve is closed arm 87 leaves contact 82 and diametrically opposite rotor arm 88 engages contact 79 preparatory to operating the valve on a further heat demand. The base-plate 25, Fig. 3, has brackets 30, 31 engaging ears 22, 23 on the valve body to hold the plate in position and carries a plate 35 located on the base-plate by a bridge 34 which engages a notch 32 in the valve stem to retain the valve in the body. The terminal plate is secured to the base-plate by spacers 41, 42 and the switch s carried beneath the terminal plate by spacers 53, 54. A circuit is shown and described in which three valves are controlled from the same power source and in which the three switches control a single circulating pump relay. In a further arrangement the circulating pump motor is driven directly from the mains through the switch and contact 81 without the use of a relay.