Abstract: A multistage space thermostat control system for controlling a refrigeration heat pump and a furnace controls the heat pump from a first stage of a space thermostat and a furnace from a second stage with anticipation circuit means associated with said thermostat control system which is changed in effectiveness depending upon the operation to reduce temperature swings in the space.

Abstract: A furnace fan control for providing operation of the fan after the termination of the furnace burner in an adaptive manner to provide for longer fan operations after the burner turns OFF, as the burner ON time increases.

Abstract: A method for measuring the running time of a signal transmitted by a transmitter and received by a receiver is devised, where the signal is transmitted and received by the same transducer. For transmitting the transmitter is driven by an electrical pulse train, and in receiving the received signal is converted back into an electrical signal. In receiving triggering is done on the trailing edge of the envelope of the received signal. At the transmitting side the transducer after its incitement is driven by a pulse train being in phase opposition to the original inciting signal and having a larger amplitude than the original inciting signal which results in a higher steepness of the envelope. At the receiving side the maximum amplitude is measured, and the triggering point of time is determined when the actually measured value of the envelope falls below a certain percentage value of the maximum value.

Abstract: A two wire rechargeable battery powered electric time controlled thermostat apparatus adapted to be connected by two wires to a source of alternating current voltage and control apparatus for controlling the supply of temperature condition medium to the space wherein the thermostat is located with a rectifying circuit means in the thermostat apparatus for recharging the battery from the source over the two wires.

Abstract: A temperature controller with a remote sensor having a high temperature cutoff with circuit means to prevent operation of the unit if tampered with to bypass a safety function. A remote sensor has a thermal fuse and diode feeding a pulsating D.C. voltage to a control circuit having a capacitor and an impedance means to which pulsating D.C. is fed. If the sensor unit is bypassed the thermal fuse in the controller burns out to render the controller inoperative.

Abstract: A pressure operated regulator valve has a regulator spring that is held in place by a spring holder. The spring holder may be inserted into a spring housing and once inserted is locked in place. Adjustment of the valve spring may be made but the spring cannot be removed.

Abstract: A control system for a refrigeration heat pump apparatus and an auxiliary heating apparatus has a two stage thermostat with the first stage normally controlling the heat pump apparatus and the second stage normally controlling the auxiliary heating apparatus. An outdoor temperature thermostat is used to transfer the control of the auxiliary heating apparatus to the first stage when the outdoor temperature drops below a predetermined value and the heat pump is deenergized as its efficiency drops at that low outdoor temperature. Each of the stages of the thermostat has an anticipation means such as a heater to artificially heat the temperature responsive element. In order to improve the control and reduce the large change in temperature when the auxiliary heat is switched over to the first stage, both of the anticipation heaters of the first and second stage are connected to be controlled by the first stage during the operation of auxiliary heat by the first stage.

Abstract: A gas burning furnace has a burner in which the premixed fuel/air ratio of the burned gas in the burner flame is measured by a flame rod sensing the ionization current. The flame rod is connected to a fuel/air controller which controls the gas and primary air to the burner to maintain the maximum flame ionization current which results in an excessive amount of gas to the burner. The secondary air to the combustion chamber is proportionally controlled to add sufficient oxidant to the gas combustion in the combustion chamber to ensure complete combustion. Other properties of the flame or combustion products can also be used.

Abstract: A space thermostat for the sight handicapped has a raised pointer on the center control point adjustment means which cooperates with raised numbers representing temperature on a cover ring surrounding the control point adjustment means whereby a sight handicapped person can place a finger on the raised pointer and move the control point adjustment means by feeling the raised number to the desired temperature setting for the desired temperature in the space.

Abstract: A humidity control having a Nylon ribbon sensing element which changes in length with moisture changes has an adjustable connecting member for changing the effect of the element on an operated switch to compensate for different expansion rates of manufactured elements.

Abstract: A power supply usable with various size loads has an input circuit receiving pulses of voltage at 25 kilohertz. The pulses are modulated in width depending upon the input to a pulse-width modulation IC receiving inputs indicative of the output voltage and current delivered to the load. A backup current limiting circuit comprising a transistor which is biased by the voltage to the load, limits the signal to the pulse-width modulation IC to limit the width of the pulse to maintain the output current within limits.

Abstract: An enthalpy control circuit has a humidity responsive capacitive element in one leg of a bridge circuit and a temperature responsive resistance element in another leg. The circuit is powered by a pulsating DC voltage of 1 kilohertz frequency for providing DC output, from an integrator connected to the output of the bridge circuit, indicative of enthalpy. A feedback from an integrator output to the bridge circuit is provided by chopping the DC output into appropriate AC for rebalance. Another feedback circuit around an amplifier provides a reference point compensated for offset voltages brought about by conditions such as temperature affecting circuit components.

Abstract: A control device for controlling temperature conditioning apparatus is connected to a thermostatic switch means having a circuit requiring a small current to maintain the circuit active during the open cycle of the thermostat switch means. A positive temperature coefficient resistor is placed in parallel with the input circuit of the control device to provide a low input impedance to the control device for maintaining the small current without activating the control device. During the operation of the thermostat with the switch closed, a larger current to the positive temperature coefficient resistor causes the resistor to increase in temperature and thus its impedance so the wattage dissipated by the PTC resistor is reduced to minimize the heat dissipation and thus the temperature of the control.

Abstract: A gas valve assembly has a safety valve and two controlled valves connected in series. A first of the controlled valves is electromatic and a second is a conventional pressure controlled valve. A control knob provides for manual control of the safety valve and for locking the first electromagnetically controlled valve in an off position. The manual control knob, when in the off and pilot positions, causes a stop member to be moved against the movable core member of the electromagnetic operator to hold the electromagnetic controlled valve in an off position.

Abstract: A control system for a refrigeration heat pump having an outdoor coil through which air is blown by a fan for extracting heat from outdoor air with means to defrost the coil periodically has a differential pressure responsive means responding to the differential air pressure across the outdoor coil. A time control means periodically operates the heat pump for a time controlled operation for predetermined time period (such as 90 minutes of elapsed operating time) and measures and stores the value of the differential pressure across the coil at the end of the time period in memory. A control means controls the heat pump between the periodically time controlled operations for normal operations for a total elapsed time operation in a pressure controlled operation until the pressure differential as previously stored occurs at which time a defrost cycle is initiated. Periodically a time controlled operation is initiated to update the pressure stored in the memory.

Abstract: Apparatus mounted adjacent a gas burner comprising a tube attached to a high voltage electrode to form a spark gap of high voltage gas ignition and flame proving system wherein raw gas is supplied through the tube to enrich the gas mixture to a lower air to gas ratio around the spark gap to enhance ignition.

Abstract: A control valve apparatus has an in line ON/OFF valve and an ON/OFF and modulating valve made by placing actuator members in a non-magnetic material tube and surrounding the tube with electromagnetic coils and an iron casing. Openings at each end provide for connections to a gas supply and an outlet for an appliance.

Abstract: A valve assembly has a rigid valve plate with a hole therein for receiving a stem member of the valve actuator. A resilient valve member is mounted on the rigid valve plate by having a peripheral portion overlapping the valve plate. To prevent high pressure gas from entering the hole around the valve stem member through the valve plate to distort the resilient valve member, a solid backup member is mounted inside the resilient valve member adjacent the rigid valve plate.

Abstract: A control system for an induced or forced draft combustion apparatus has a single pressure transducer for providing an electrical signal indicative of pressures by alternately responding to the fuel pressure to the combustion apparatus and the fuel pressure plus the induced draft lower suction pressure. The signal output of the transducer is connected to a controller for controlling the fuel flow to maintain a predetermined fuel/air ratio for efficient and safe combustion of the fuel in the combustion apparatus.