Abstract: Flow control valves (19) are provided and interfaced with the HVAC ducts (14) at the efferent ends (16) in adjoining rooms of a structure. A flow control command device (29), mounted on the wall of the structure (25), is provided to control the flow of air through the HVAC ducts (14) in response to flow control commands. Flow control commands are transmitted by wireless means to the command decoder (22) and converted to flow control signals. A flow control signal bus (21) is provided to connect the flow control signals to the flow control valves (19). A master thermostat (32) is connected directly to the HVAC system (10) and in series with a slave thermostat (30). This series thermostat connection causes control of the HVAC system (10) to be determined by the thermostat located in the room that receives the higher air flow.

Abstract: A damper position control device for use in an automotive air conditioning system. The damper position control device includes a motor actuator which rotates an air mix damper in forward and reverse directions, an electric power source, and an electric power source switch device. The motor actuator includes a motor, a gear which is operatively connected to the drive shaft of the motor and an air mix damper and which rotates the air mix damper in forward and reverse directions in accordance with the rotations thereof, and a rotation control device including a regulator which governs the upper and lower rotational limits of the drive shaft of motor and gear. The regulator includes at least three fixed contacts each of which is parallel to the others, but has the different length, and a movable contact which is in contact with at least two of the fixed contacts and which cycles along fixed contacts in accordance with the rotations of the drive shaft of motor and gear.

Abstract: It is possible to accurately and easily detect an abnormality in an electronic expansion valve without cutting or separating an electronic expansion valve from a cooling medium circuit. When an excitation pulse current from a drive circuit is output, a magnet rotor of an electronic expansion valve rotates. A hall element detects the position change of the magnet rotor at this time as detection pulses. The number of the detection pulses at this time is sent to a first up-down counter via an amplifier and a rectifier and is counted. The number of excitation pulses is also counted by a second up-down counter. The abnormality detection element judges that there is normal operation when the two count numbers of the first and second counters are in agreement, and that there is an abnormality when the two are not in agreement.

Abstract: A system for controlling vehicle passenger compartment comfort. An electronic controller receives input from: (i) a thermistor array sensing blower plenum discharge temperature, (ii) a user movable Level Select Control (iii) a potentiometer sensing the position of a servo driven heater core water valve, (iv) an engine rpm tachometer generator and (v) a blower speed signal. The controller drives the servomotor for the water valve at a "High" rate until the valve position potentiometer indicates that the valve is within fifteen degrees (15.degree.) of the target, whereupon the controller drives the servomotor at a "Low" speed.

Abstract: Humidity control system for regulating the relative humidity of air which is forced through a spray painting booth. The humidity control system employs a water spray nozzle which atomizes water to quickly change the relative humidity and temperature of the ventilation air moving through the paint spray booth. A flow control valve which opens at a predetermined rate to control the water flow to the water spray nozzle in a manner which provides for an overdamped response to changes in the relative humidity level. The humidity control system further includes a motor for operating the flow valve, a controller for energizing the motor, and suitable sensors for providing feedback to the controller. The low predetermined rate at which the flow valve opens allows the water flow through the flow valve to be modulated by the length of time which the motor is energizes.

Abstract: A temperature regulating apparatus for an air-circulated refrigerator is disclosed, capable of keeping the refrigeration room temperature constant by way of closely regulating the flow rate of cold air admitted into the refrigeration room. Also disclosed is a control device for controlling operation of the temperature regulating apparatus. Such a temperature regulating apparatus comprises a core member 50 either extendible to open up the cold air inlet port 12 or retractable to close off the same. A multiple turns of a coil 54 surrounds the core member 50 in order to produce a varying level of inductance i.e. an electrical signal proportional to the axial displacement of the core member 50. This electrical position signal is transmitted to a control device 20 which serves to control the operation of the damper flap actuator based on the temperature signal from a temperature sensor 22.

Abstract: A refrigeration system control for a refrigerated container unit in which a compressor suction modulating valve is controlled during light loads near its valve seat by rapidly moving the suction modulating valve to an open position away from the valve seat and then moving the suction modulating valve to the desired position.

Abstract: An automotive air-conditioner has a casing forming an air passage through which an air passes and a film damper slidably disposed in the casing in such a manner to face to the air passage. The film damper having openings opens and closes the air passage. Holes are disposed on the film damper for indicating a position of the opening: Photointerrupters are disposed on the casing to detect the holes and output a present position signal that shows a present position of the film damper. A mode setting portion outputs a target position signal that shows a target position of the film damper. A microcomputer compares the present position signal with the target position signal, so that the microcomputer controls the film damper to stop at the target position.

Abstract: A system for controlling vehicle passenger compartment comfort. An electronic controller receives input from: (i) a thermistor array sensing blower plenum discharge temperature, (ii) a user movable Level Select Control (iii) a potentiometer sensing the position of a servo driven heater core water valve, (iv) an engine rpm tachometer generator and (v) a blower speed signal. The controller employs proportional-integral-derivative (PID) strategy in a microprocessor to generate a control signal for operating the heater core valve servo motor to maintain the plenum discharge air at a constant temperature irrespective of wide swings in engine rpm/water pump speed or user selector changes in blower speed.

Abstract: A conventional thermostat has separate high and low temperature switches for controlling a reversible motor driving a modulating damper or valve whose position controls the temperature of an enclosure by controlling the injection and removal of heat from the enclosure. In the improvement, relay contacts control the current flow to the thermostat's heat and cool anticipator resistors, and only relay control current flows through the motor windings. This avoids degraded motor performance resulting from anticipator resistor current flow through the motor windings and makes the anticipator resistor current level independent of the motor impedance. The relay chosen is one whose activating element draws very little current to close the relay contacts. The preferred embodiment uses a solid state relay which includes a light emitting diode whose light emissions control the impedance of a semiconductor circuit forming the "contacts" of the relay.

Abstract: A system for controlling temperature of air to be discharged into a cabin of a vehicle in an automatically controlled air conditioner system of an automotive vehicle. The air conditioner system is provided with a cooling unit and a heating unit for cooling and heating conditioning air in the air conditioner system for delivery to the cabin of the vehicle. The air conditioner system includes a mechanism for mixing the cooling air and the heating air in a stepwise manner so as to generate a controlled temperature of conditioning air to be discharged into the vehicle cabin with a moderate adjustment in transition so as to maintain a desired vehicle cabin temperature.

Abstract: A method of closely controlling the supply air temperature delivered from an air conditioning unit into a mobile cargo container wherein the supply air temperature is compared to a desired set point temperature and a suction control valve in the air conditioner compressor inlet line is adjusted in response to the sensed difference between the supply air temperature and the set point temperature. Three different preprogramed control modes are available which are selected automatically in response to the amount of deviation between the compared temperatures that are used to bring the supply temperature down the set point temperature and hold it under steady state conditions within .+-.0.25.degree. C. of the set point. A trim heater is placed in the supply air passage to warm the supply air any time the control valve is in a full closed position. This increases the heating load on the unit so that operating time of the unit will be prolonged and the compressor will not be cycling ON and OFF.

Abstract: A hot/cold water mixing device includes a hot water supply valve disposed in a hot water feed pipe for regulating the amount of hot water passing therethrough, a cold water supply valve disposed in a cold water feed pipe for regulating the amount of cold water passing therethrough, a water mixture pipe connected between the hot and cold water feed pipes and a water outlet, and a control mechanism for controlling an actuating mechanism to open and close the hot and cold water supply valves complementarily to each other.

Abstract: A method and apparatus for controlling the mixing of two fluids to form a mixed fluid, and the volume discharge rate of the mixed fluid. In a particular application, the two fluids are hot and cold water, and the mixing is controlled to effect temperature control of the mixed water. A specially-designed integral temperature control and volume control valve is included as part of the system. Operation of the valve is controlled by two stepper motors, which in turn are controlled by signals developed by a control unit. Means for setting a desired temperature and volume rate discharge, as well as means for displaying the set temperature and volume rate discharge, are also provided.

Abstract: Disclosed is a temperature control system for airconditioners having air blend doors which are controlled by electrical signals related to the room temperature such that the amount of cool air to be reheated by a heater and the amount of cool air bypassing the heater have an appropriate proportion so as to achieve a desired room temperature, and a sensor which provides an electrical signal representing the degree of opening of the air blend door. The degree of opening of the air blend door is recognized with reference to the electrical signal from the sensor corresponding to the full-closed position or full-open position of the air blend door. The system has a function of zero-adjusting the sensor automatically following the control operation.

Abstract: A control system for heating installations which is responsive to a pre-selected target air temperature and a pre-selected radiant heat output.

Abstract: An air conditioning control system has inputs for room temperature and air velocity voltage signals. Both signals are scaled and compared to determine which signal is larger, and the magnitude of the difference. The control circuit drives a variable speed damper motor in a direction determined by the greater of the two scaled input signals. The motor is driven at a rate proportional to the magnitude of the difference between the two signals. Means for setting the maximum and minimum open damper positions are provided within the control circuit.

Abstract: A system for automatic control of water temperature by means of a plurality of pushbuttons or their equivalent bearing indicia identifying a range of available temperatures which, when actuated through appropriate circuitry, control the water valve setting as to the proportion of hot water to cold water and vice versa and as to the volume of water.

Abstract: An electronic circuit controls a non-linear electromechanical valve in order that the temperature of approximately 25 gallons of coolant water within a reservoir may be maintained within +2.8.degree. C. to -0.0.degree. C. of a set point temperature from 35.degree. F. to 100.degree. F. The valve regulates circulation of such coolant within a secondary cooling loop incorporating a non-linear heat exchanger for thermal exchange with building water flowing from 20 to 30 gallons per minute. The reservoir coolant water is subject to an essentially instantaneously variable thermal load of 0 to 20 kilowatts due to circulation through logic modules in a primary coolant loop. The electromechanical valve control circuit receives an external set point temperature signal, and a reservoir coolant temperature signal which is offset in conversion from degrees Kelvin to degrees Centigrade.

Abstract: The invention relates to thermostatic apparatus for controlling the heating fluid supply temperature in a central heating installation having at least two radiators in different rooms. With each room having a thermostat for controlling the radiators therein, the apparatus operates so that the most active thermostat is given priority in controlling the temperature of the heating fluid.

Abstract: A closed loop control circuit for regulating the response of an automatic temperature control system is disclosed. The temperature control system provides automatic regulation of the temperature for the passenger compartment of a vehicle by positioning a blend air door in response to three control parameters. Two of the control parameters, the actual temperature of the passenger compartment and the desired temperature of the passenger compartment, are serially combined in one leg of a bridge circuit and compared against another leg of the bridge presenting the third control parameter, the position of the blend door. An unbalanced condition in the bridge circuit is corrected by the repositioning of the blend door until the error between the two legs is nulled. Repositioning is accomplished by a pair of differential amplifiers which detect the sense of the error and thereafter provide an interrupter control function to a vacuum modulator.

Abstract: An electronic reversible motor operated valve assembly adapted to be controlled by a two-wire thermostat. The assembly includes a valve casing having a pivotally mounted valve member, and a reversible motor drive unit having forward and reverse motor windings which, when alternately energized, effect pivoting of the valve member between closed and open positions to control fluid flow through the valve casing. The assembly includes a triac having a first annode and a gate coupled across the two wires of the thermostat, and having a second annode and the gate coupled across separate end terminals of the motor windings. Commonly connected end terminals of the motor windings and the first annode of the triac are coupled to an A/C power source to afford biasing the triac. When the thermostat switches to an off state, the triac is biased on and the reverse motor winding is energized to pivot the valve to the open position.

Abstract: A control system for proportionally operating an actuator is disclosed having a condition responsive device comprising an element movable in response to a sensed condition and a sensing device for sensing the movement of the element, the actuating means being connected to the sensing device for movement in response to the movement of the sensing element and a feedback mechanism responsive to the movement of the motor for repositioning the sensing device and the sensing element relative to one another for providing proportional control.

Abstract: Apparatus for controlling the opening and closing of windows in a greenhouse or other structure which includes temperature sensing means for producing a control signal, means for producing a second control signal corresponding to a temperature at which the windows are to be opened, means actuated by the windows for producing a third control signal, means comparing the third signal with the first and second signals to produce a comparison signal which functions to operate motors to open and close said windows.

Abstract: A heating control system for automatically controlling the temperature within a space is provided. The heating control system includes a temperature sensor for detecting changes in temperature without the space and in response thereto producing a control signal having a substantially linearly variable potential, the increase or decrease in the variable potential being directly varied in response to changes in temperature without the space. A heat supply includes a control valve adapted to be selectively opened to increase the rate at which heat is supplied to the space and be selectively closed to decrease the rate at which the heat is supplied to the space. A rheostat having a shiftable contact is coupled to the control valve and is disposably controlled thereby to produce a variable reference feedback signal having a substantially linearly variable potential in response to the selective opening and closing of the control valve.

Abstract: A stack damper control arrangement for use in a heating system including a furnace having a fuel-fired burner apparatus and a vent stack for conducting combustion products away from the burner apparatus and a damper plate pivotally mounted within the stack and movable between a fully open and a fully closed position, includes a reversible drive motor which is energizable in response to a request for heat to drive the damper plate to the open position, a first limit switch operated when the damper plate reaches the open position to effect the deenergization of the motor, the motor being reenergized at the end of the heating cycle to drive the damper plate to the closed position, and a second limit switch operated when the damper plate reaches the closed position to effect the deenergization of the motor.