| 摘要 |
<p>1,146,096. Automatic temperature control systems. LANDIS & GYR A.G. May 1, 1967 [June 22, 1966], No.20110/67. Heading G3R. An automatic temperature ventilation or air conditioning control system has the sensing and setting members fed with A.C. and connected by a single pair of heads to a differencing circuit which controls the restoring circuit. Positive half cycles from an A.C. supply 4 flow serially through a thermistor 9 of either sign, diodes 11, 16 and resistor 17, and negative half waves through a setting resistor 10, diode 12, resistor 18 and diode 15, the voltages across resistors 17, 18 charging capacitors 21, 22 in series opposition, the difference being applied to a transistor amplifier 26, energizing a relay 39 or 41 according to the sense of the error. For proportional control, a variable resistor (42) Fig. 2 (not shown) driven from a heating fluid-flow valve motor may be series connected with resistor 17. A further resistor (44) may adjust the dead zone. A further circuit 2 may be connected across terminals 45, 46 for combined heating and cooling systems. Resistors 9, 10 may be multiplied and may be of relatively high resistance to resistors 17, 18. The amplifier 26 is supplied from a potentiometer comprising a resistor 31 and diode 32, the diode having preferably the same transmission characteristic as transistor 33 to assist stabilization.</p> |
