Abstract: A method for adjusting the continuous speed of the blower of a heating and/or cooling system of the type including a thermostat having a mode selector switch which has at least one heating position, a cooling position, and an off position, a fan switch having an on position or state and an auto position or state, and a programmable control device responsive to the thermostat for generating speed select signals for use in setting the speed of the blower motor. The programmable control device is programmed or reprogrammed so that, when the mode selector switch is in its off position or when there is no call for heating or cooling at the thermostat, time dependent movements of the fan switch away from and back to its on position are recognized as requests for changes in the continuous speed of the blower motor.

Abstract: A fan motor is run at minimum capability at predetermined time intervals for a certain period of time when a heating mode is set but a blowing is stopped. Thus, with air around a temperature sensor disposed between inlet openings and a heat exchanger being not affected by the heat of the heat exchanger, measurement of a room temperature is carried out by the temperature sensor.

Abstract: A forced air heating and/or cooling system utilizing a permanent split capacitor (PSC) or shaded pole AC induction motor and including an actuator for energizing a source of heating and/or cooling effect may be controlled by a controller circuit which is operable to continuously vary the speed of the fan motor during a start-up phase and a shut-down phase of the heating and/or cooling cycle. The controller circuit includes terminals for connection to the source of electrical energy for the heating and/or cooling system and for connection to the system controls without altering the control function or circuitry thereof.

Abstract: A system and method for preventing a computer system from overheating when a processor or software controlling the processor which controls the cooling system fails. The apparatus utilizes a watchdog timer which receives periodic signals confirming proper operation of the processor. When these status signals are not received, the watchdog timer transmits signals causing the cooling system that prevents overheating of the computer system.

Abstract: An interface for a blower in an automotive vehicle. The interface allows a blower requiring a DC control voltage to be controlled by either (1) a DC control voltage or (2) a Pulse Width Modulated (PWM) signal. The interface converts the PWM signal to a DC voltage.

Abstract: A method for operating a heating or air conditioning system, especially for motor vehicles is provided, in which a temperature control fluid is drawn in via a discharge blower whose discharge power can be regulated, and is blown out after processing through at least one exhaust duct, whose outlet cross section can be regulated via a corresponding controllable control element. Each control element for outlet cross section regulation is automatically adjusted to assume a position that depends upon the outlet temperature of the temperature control fluid. The discharge blower power is adjusted according to a curve as a function of this outlet temperature.

Abstract: Systems and methods for controlling a draft inducer for use with a furnace. The draft inducer includes a fan for moving combustion chamber gases for inducing a draft in the furnace combustion chamber that causes a pressure drop across a heat exchanger. The density of the gases flowing across the heat exchanger and the fan differs from a first operating state of the furnace to a second operating state of the furnace. A motor drives the fan in response to a motor control signal so that different motor speeds result as a function of the density of the gases flowing across the fan. A control circuit generates the motor control signal as a function of a first set of speed/torque curves until a speed signal indicates that the motor has reached a predetermined speed. After the speed signal indicates that the motor has reached the predetermined speed, the control circuit generates the motor control signal as a function of a second set of speed/torque curves.

Abstract: The residential structure ventilating apparatus disclosed herein employs a variable speed exhaust fan. The speed is responsive to a sensor which detects air temperature at the exhaust port. The fan is energized when the sensed air temperature rises above a first preselectable temperature and the external environmental air is cooler that the air at the exhaust port. The fan speed is increased progressively from about one-half full speed at the preselected turn on temperature to full speed at a predetermined higher temperature. The fan is turned off when the exhaust port temperature falls below a second preselected temperature, lower than the first preselected temperature or when the external environmental temperature rises above the inside temperature, the fan speed being essentially constant between the first and second preselected temperatures.

Abstract: A cooling/heating apparatus having an automatic ventilating function and its method switches the ventilating function and the cooling/heating function in response to the pollution state of room air and maintains the room air in a pleasant state. The apparatus and method rotates the cooling/heating fan and the ventilating fan to be mutually supplemented and completed by the output of a gas sensor which changes its resistance value in response to the air pollution state within a room. The ventilating fan is rotated instead of said cooling/heating fan when the room air is polluted and ventilates the polluted air within a room.

Abstract: A two-stage furnace is operable at a high fire full rate mode and at a low fire partial rate mode when there is a call for high heat or low heat, respectively. In order for the furnace to be less prone to vent gas condensate formation when operating at low fire, and to permit the heat exchanger and vent pipe to reach equilibrium as soon as possible on both low fire and high fire, a shorter blower-on delay is provided for high fire and longer blower-on delay is provided on low fire.

Abstract: A method of cooling a computer having a plurality of components and at least one variable rate cooling unit including the steps of obtaining a cooling requirement for at least one of the components and varying the rate of at least one of the cooling units based on the obtained cooling requirements. In addition an apparatus for cooling a computer having a plurality of components, the apparatus including at least one variable rate cooling unit, an apparatus for obtaining a cooling requirement for at least one of the components, and an apparatus for varying the rate of at least one of the cooling units based on the obtained cooling requirements.

Abstract: A cooling system (10) with a control temperature sensor (24) for sensing the temperature of a coolant coil (14) for control of a coolant coil fan (18) in cooperation with ambient temperature sensed by a thermostat (30) to obtain optimum utilization of residual cooling power of the coolant coil (14) after the condenser (28) has been deactivated and to protect against overcooling and consequent icing of the coolant coil (14) in the event of inadvertent failure of the thermostat (30) to turn off the condenser(28).

Abstract: An interface is disclosed for operatively interconnecting a conventional thermostat and an electronically commutated motor ("ECM"). The interface provides enable, heating and rate signals to the ECM in response to the conventional fan, heat, valve and airflow signals from the thermostat.

Abstract: A field installable device for a conventional heating and air conditioning system (HVAC) is provided which operates a blower fan in conjunction with a standard thermostat. Presently, HVAC systems operate in four modes: heating, cooling, off and fan "on". The device includes a multi-pole, multi-speed motor and a control operatively connected between the thermostat and the motor. With the fan switch in the "on" position and heating or cooling called for, the control causes the blower to operate at a high speed, which may be different for heating or cooling. When the pre-selected temperature is reached the particular thermal operation (i.e., heating or cooling) is stopped. The control switches the motor to a speed substantially slower than the operating condition speed to provide continuing air circulation until the thermostat again calls for thermal operation. With the switch in "auto" position, the blower operates similarly to present systems.

Abstract: Enhanced cooling of electronic equipment (14) within an enclosure (10) is obtained by prescribing the relationship between the maximum allowable temperature difference .DELTA.T.sub.m between the exhaust and inlet air temperatures T.sub.e and T.sub.i versus the actual inlet temperature. Once a relationship between the maximum allowable temperature difference .DELTA.T.sub.m versus inlet temperature T.sub.i has been established, then each fan (22) which draws air through the enclosure is controlled so that the fan's speed is increased when the actual temperature .DELTA.T exceeds the maximum allowable temperature difference .DELTA.T.sub.m by a predetermined tolerance factor. In this way, factors such as increased heat load in the enclosure (10), diminution of the air flow therethrough, as well as an increase in the inlet air temperature, are taken account of in the control of fan speed.

Abstract: To reduce air suction noise in internal air recirculation mode of an air conditioner for an automotive vehicle, a difference in temperature between a target value and an actual value is calculated and the amount of blown air is decreased in the internal air recirculation mode, as compared with that in the external air introduction mode, by reducing a voltage applied to a blower fan motor, only when the calculated temperature difference is a predetermined value or less.

Abstract: A controller for a dual speed induction motor selectively applies operating power to the low speed motor terminal or the high speed motor terminal according to the open circuit/closed circuit condition of a low temperature thermostat and a high temperature thermostat. For low speed operation, operating power is conditionally applied to the low speed motor terminal through the low temperature thermostat and through the normally closed circuit of a single pole, double throw switch. For high speed operation, operating power is conditionally applied to the high speed motor terminal through the high temperature thermostat and the normally open circuit of the single pole, double throw switch. The operating position of the single pole, double throw switch is determined by a solenoid which is connected in series circuit relation with the high temperature thermostat.

Abstract: Precision measuring machine (10) has a bed (12) with a tailstock (14) and headstock (16) mounted thereon. Anvils (36, 42) are respectively mounted on the tailstock and headstock. Duct walls enclose the lower portion of the bed so that fan (62) can move air therepast. Cap shrouds (72, 82) receive air from fan shrouds (68, 84) to flood air over the tailstock and headstock. Anvil shrouds (76, 90) respectively cover anvils (36, 42) and receive air through tubes (80, 92) to also flood the anvils with air. In this way, the precision measuring machine is bathed in ambient air to reduce dimensional changes due to temperature changes.

Abstract: Apparatus and method for controlling a motor having a stationary assembly with a plurality of winding stages for carrying motor current and further having a rotatable assembly in driving relation with a blower in an air handling system. The apparatus provides control of the blower speed over a range of static pressure variations to maintain relatively constant preselected rate of air flow in the system. The apparatus receives a preselected flow rate signal representing the preselected air flow rate. A microprocessor, responsive to both the preselected flow rate signal and a speed signal, generates a desired torque signal which is a function of both the preselected flow rate signal and the speed signal. The desired torque signal is compared to a signal representing motor torque and a comparison signal representing the comparison is generated.

Abstract: A testing system for determining accelerated weathering characteristics of various items such as fabrics and paint samples. Rack means are provided for carrying samples to be tested. A source of irradiation of the inner-facing surfaces of the samples carried on the rack is also provided, along with a blower system for directing a stream of air through the rack. In accordance with this invention, a generally conical member is positioned in the stream of air to redirect the stream outwardly in a generally conical flow path. The generally conical flow path is positioned by the conical member to flow across the inner-facing surfaces of the samples carried on the rack.

Abstract: Electronic control system for a gas-fired/hot air furnace includes a primary control unit which controls the flow of fuel to the furnace. The furnace has heating and cooling space thermostats and a comfort fan to supply heated or cooled air to the space being monitored by the thermostats and an induced draft blower which supplies combustion air into the furnace for heating. A first switch and associated relay drive selectively energizes the comfort fan for low speed heating operation and a second relay switch and associated relay drive selectively energizes the comfort fan for high speed cooling operation. Actuation of the heating thermostat energizes a third switch and associated relay drive which energizes the induced draft blower. A high temperature thermostat located to sense excessive furnace temperatures is also connected to actuate the third relay to energize the induced draft blower in an excessive temperature condition.

Abstract: A variable speed motor is regulated responsive to the load torque acting on the blower wheel. The load torque acting on the blower wheel is determined by means of a coast down procedure in which the motor is briefly de-energized and the rate of angular change d.omega./dt is determined. The load torque acting on the blower wheel can be determined knowing the moment of inertia and d.omega./dt. The average motor RPM during the coast down is then related to a torque value where an RPM vs. CFM relationship has been empirically determined for that blower wheel. A microprocessor then computes the final motor RPM necessary to achieve the desired air delivery (CFM) using the fan law equations.

Abstract: A fire condition detection and control system for use with air moving and filtering units. The system includes one or more remote fire condition detection units, which sense heat or smoke and, upon such sensing, transmit a signal indicative of an alarm condition to one or more air moving and filtering units located within a containment area. The transmission is by wireless radio frequency transmission and/or a wired transmission line or cable. The air moving and filtering units detect the alarm condition and disconnect power to the blower motor of the air moving and filtering unit. The receiver and control circuitry may be integral with the air moving and filtering unit, or may be part of a separate control unit that plugs into conventional air moving and filtering units.

Abstract: A temperature-controlled accelerated weathering test apparatus concentrates solar radiation upon target samples and controls the flow rate of cooling ambient air circulated across the target samples in order to maintain the target sample temperature substantially constant despite variations in ambient daytime temperature and variations in solar radiation intensity. A temperature sensor is secured to an aluminum panel mounted upon the target board of the test apparatus proximate to the target samples for generating an electrical signal relating to the temperature of the target samples. The temperature sensor and related aluminum panel are coated black to enhance absorbtion of solar radiation. A controller responsive to the electrical signal generated by the temperature sensor controls the application of electrical power to a blower motor used to circulate cooling ambient air across the target samples.

Abstract: A device is disclosed which causes a fan of a heating and/or air conditioning system to continue to run until the temperature in the duct work of the system reaches a desired temperature, so as to remove all heated and/or cooled air from the system, however, the device is designed so as to not cause the fan to be actuated due to changes in the duct work temperature which are due to changes in outside temperature or causes other than the operation of the system. A sensor which is located in the duct work controls the operation of the fan in response to temperature changes only if the sensor control circuit is first energized by the operation of the system.

Abstract: The fan speed controller disclosed herein is particularly useful in the cooling of electronic equipment and provides a feedback control characteristic from an exhaust air temperature sensor such that the change in outlet temperature over the range of air flow rates is substantially equal to the change in temperature rise of typical heat generating devices in electronic equipment over that same range. Accordingly, device temperature is maintained substantially constant over a range of varying input air temperatures. Preferably, the controlled fan includes a d.c. motor which is energized in a pulsed d.c. mode to prevent stalling or instability at low flow rates.

Abstract: A furnace is operated such that the air-fuel ratio and the temperature rise are maintained constant so that the efficiency remains constant over the range of operation.

Abstract: The fan speed controller disclosed herein mounts directly on a fan whose speed is to be controlled and provides electronic speed control circuitry mounted in a disk-like enclosure aligned with the fan hub. The enclosure is compartmented and apertured to provide a representative air flow past a temperature sensitive element employed by the circuitry. Fan speed is controlled as a function of air temperature above a sharply defined minimum to provide effective cooling with minimal noise generation.

Abstract: An adaptive motor control for a furnace with or without an evaporator coil determines and delivers the desired CFM for each thermostat cycle. Specifically, a circulating air blower driven by an ECM is initially set at a known duty cycle for each thermostat cycle and the delivered CFM is calculated. The RPM necessary to deliver the desired CFM is then determined and the ECM is set accordingly.

Abstract: In an air conditioning system for automobiles including a temperature control apparatus having temperature setting device for setting a vehicle compartment temperature, a temperature sensing device for sensing an actual vehicle compartment temperature, a temperature difference signal device for generating a difference signal in accordance with a difference between the set vehicle compartment temperature and the sensed actual vehicle compartment temperature, and air flow control device for controlling the rate of air flow from a blower so as to provide varying air flow rates up to a maximum air flow rate in accordance with the value of the difference signal, a detecting device for detecting that the air condition system is at a heating operation, and a control arrangement responsive to the output from the detecting device and the value of the difference signal for controlling the air flow rate control device so that the rate of air flow from the blower is maintained at a predetermined flow rate which is less t

Abstract: An automobile air conditioning system is provided with a control system for controlling the flow rate of hot or cool air discharged into the passenger compartment. The air flow rate is controlled in relation to the sensed value of the ambient air temperature and the temperature of a heat source of the air conditioning system. If the sensed temperatures are lower than predetermined reference levels, the air flow rate is gradually increased at a moderate increasing rate. The air flow rate is more rapidly increased when the sensed heat source temperature is higher than the reference level.

Abstract: An automobile air conditioning system is provided with a control system for controlling the flow rate of hot or cool air discharged into the passenger compartment. In this control system, the air flow rate is increased with an increase of the absolute value of the temperature difference between a predetermined reference temperature and a room temperature of the compartment detected by a sensor, and is decreased with a decrease of the absolute value.

Abstract: Central air conditioning equipment which performs air conditioning for a plurality of rooms, comprises a terminal air quantity control unit which is installed in order to communicate with each room and which controls the quantity of the air stream which is distributed to each room through a duct, and an air quantity control device, attached to an air conditioner, which controls a blower to reduce the blown air quantity until at least one of dampers reaches a first position to allow air flow when all of the dampers are not in the first position, which controls the blower to decrease the blown air quantity when an air quantity detected by an air quantity sensor is smaller than an air quantity set by a setter while at least one of the dampers is located in the first position, and which controls the blower to maintain the blown air quantity when the air quantity detected by the air quantity sensor is equal to the air quantity set by the setter.

Abstract: An air supply and return system for heating and cooling a room, including an air flow loop having a first set of openings positioned high in a wall of the room (high vents) and a second set of openings positioned low in a wall of the room (low vents). The air flow loop includes a reversible air moving device, heating and cooling coils, and ducts connecting the reversible air moving device, filters, and the heating and cooling coils to the high vents and the low vents. During the cooling cycle, air is withdrawn from the room through the low vents, circulated with high air flow by the air mover through the ducts, filter, and the cooling coils, and discharged to the room from the high vents. During the heating cycle the air mover, and thereby the direction of air flow within the duct system, is reversed.

Abstract: A control system is disclosed for use in a restaurant having a forced air input air conditioning and/or heating system and a grill with an exhaust fan operating therewith. The invention includes an exhaust fan sensor means for monitoring the operative condition of the exhaust fan. A grill control means is provided for controlling the on/off operation of the grill. An air input sensor means senses the operative condition and the air flow of the air conditioning and/or heating system. A controller is connected for monitoring the sensors and for inhibiting operation of the grill upon an inoperative condition of the exhaust fan. The controller further inhibits operation of the air conditioning and/or heating system upon an inoperative condition of the exhaust fan thereby insuring the correct temperature within the restaurant. The invention may optionally include a stand-by power supply, a line voltage monitor and programmable thermostatic controller.

Abstract: A control circuit for a typical home heating and cooling system, including means to control relative humidity, is shown. The control circuit includes a standard 24 volt transformer in conjunction with a thermostat selector switch and a fan selector switch. As is common in many heating and cooling systems, a multiple speed blower is included with the higher speed being used during the cooling cycle. In addition to the standard relay for normal operation of the multiple speed blower motor in the typical home heating and cooling system, the control circuit includes an economizer control relay which activates when the thermostat selector switch is in the cool position and the fan selector switch is ON to cause the blower motor to run at a high speed while the compressor is running and at a low speed while the compressor is not running.

Abstract: The control system maintains air temperature comfort in a zone of a commercial structure. Outside air is supplied into the zone for ventilation purposes and for cooling the zone to the desired temperature whenever possible to minimize the use of mechanical air cooling apparatus and thereby reducing energy consumption. Heating and cooling coils temperature condition the supplied air. A pneumatic control system selectively activates the heated, cooled or ventilated air supplied in the zone. A two-speed supply fan, controlled by the pneumatic control system, operates in a first state at only low speed to reduce energy consumption, or in a second state at automatic thermostat two-speed control (high or low). The fan in this second state operates at low speed except when maximum cooling is required and then switches back to low speed operation from high speed when the ambient temperature in the zone approaches the desired temperature.

Abstract: A control system adapted to be secured to a solid fuel burner, such as a fireplace or a stove, to create and regulate forced fluid heat exchange and forced draft in the burner. The system comprises an electrical draft inducer/damper mounted in the burner flue, a fluid heat exchanger mounted over the burner firebox, and a control apparatus capable of deactivating the draft inducer/damper and the heat exchanger, automatically damping the flue, when combustion in the burner subsides. The control system, including the draft inducer/damper and heat exchanger, may be incorporated with a solid fuel burner, thus comprising a heating system.

Abstract: A control circuit for a typical home heating and cooling system is shown. The control circuit includes a standard 24 volt transformer in conjunction with a thermostat selector switch and a fan selector switch. As is common in many heating and cooling systems, a multiple speed blower is included with the higher speed being used during the cooling cycle. In addition to the standard relay for normal operation of the multiple speed blower motor in the typical home heating and cooling system, the control circuit includes an economizer control relay. The economizer control relay activates when the thermostat selector switch is in the cool position and the fan selector switch is ON to cause the blower motor to run at a high speed while the compressor is running and at a low speed while the compressor is not running.

Abstract: A ventilated enclosure is formed by an air duct, one end of which is closed ff by a partition pierced with ventilation apertures and the other end of which is closed off by a wall to which is attached at least two fans and which is provided with openings through which air drawn into the interior of the enclosure from its exterior is passed. Each fan is provided with a detection device for detecting inadequate ventilation. The detection device is positioned in the area which is swept by the stream of air which is produced by the associate fan when in operation and generates a signal when the output of air from this fan falls below a predetermined limiting value. Each detection device consists of a thermal detection element designed to emit a signal when its temperature becomes equal to a predetermined temperature threshold and an air non-return casing.

Abstract: An improved fan controller for forced-air temperature conditioning apparatus for buildings, such as for example, forced warm air furnaces in which the fan turn-off is controlled as a function of the difference in temperature between the plenum temperature and the return air temperature.