Abstract: A variable air volume ventilation system (10) is disclosed in which the output air flow from a supply fan (13), delivered through a supply duct (11) to various places within a building, is returned by a return duct (15) through a return fan (17) and then through a connecting duct (18) back to the inlet (20) of the supply fan (13). The static pressure in the supply duct (11) is sensed by a static pressure sensor (40), and the output signal indicative of pressure is used by a variable frequency power supply (44) to provide power to drive the fan motors (36, 37) at a frequency inversely proportional to the difference between the sensed static pressure and a desired static pressure, thereby adjusting the flow through the ventilation system to match demand. Outside make-up air is provided through an outside air duct (50) and is fed into the return duct (15) at a position (52) near the inlet (16) of the return fan (17).

Abstract: An air mixing control type air conditioner used for an automobile for controlling the diffusing air temperature so as to follow a main temperature control at an assistant driver's seat side for a main temperature control at a driver's seat side and to also maintain desired high or low temperature difference with respect to the main temperature control. Thus, the diffusing air temperature of the sub control system following the main diffusing air temperature can be controlled in a range of a predetermined constant temperature difference with respect to the main diffusing air temperature of the main control system. Accordingly, desired automotive cmpartment temperature can be obtained merely by a single main control lever.

Abstract: An automotive air conditioning apparatus is provided which, in raising the temperature inside a vehicle cabin from a low level to a preset higher level in a maximum cooling mode or in lowering the cabin temperature from a high level to a preset lower level in a maximum heating mode, suitably controls in an initial stage of the procedure the revolution speed of a blower but does not drive an air mix door at all to keep it at an existing opening degree. When the revolution speed of the blower reaches a predetermined lowest speed, the air mix door begins to be driven to vary its opening degree progressively and suitably while, at the same time, a first reference temperature level for deactivating a compressor associated with a cooler is shifted to a second reference temperature level.

Abstract: An apparatus for controlling an air conditioner for an automobile comprises: an air conditioning unit including a heater unit for heating air passing through an air supply duct and a device for adjusting the amount of air passing through said duct, an air distributing unit for effecting switching among a plurality of air supply outlets into a compartment of the automobile, the unit including a ventilation supply outlet, and an air bypass containing an air valve for supplying cool air upstream of the heater unit to the ventilation supply outlet; a compartment temperature setting unit for setting a desired temperature value within the compartment; sensing units for sensing the temperature within the compartment and the amount of insolation in the compartment; a processing unit responsive to output signals from the compartment temperature setting unit and the sensing units for determining the desired temperature of air supplied to the compartment and for deciding relationships between the air supply temperature

Abstract: In a heating apparatus for motor vehicles, there is provided means for permitting part of air just heated by heater means provided in the apparatus to be directed toward a region upstream of the heater means so as to be again heated by the heater means, thereby causing the temperature in the vehicle chamber to be rapidly elevated, while at the same time preventing the humidity therein from being increased.

Abstract: In a heating and/or cooling system, two heat transmitting media are blended into a blended medium with adjustable temperature. The motor (M) of a blending member is controlled pulsewise in both directions by comparison pulses from a setpoint/actual value temperature comparison.In order to provide a system which is simple to construct, which is wear-resistant and which permits a quick and accurate adjustment of the blending member, the circuit arrangement for controlling the motor (M) contains a first pulse generator (TB1), which generates pulses of constant width commencing respectively with the end of a comparison pulse and is connected to second and third pulse generators (TB2, TB3). The second and third pulse generators (TB2, TB3) generate pulses of a width proportional to the actual value or the setpoint of the temperature, respectively, which directly control the motor (M) after comparison in a comparator (CO).

Abstract: A heater unit for use in an air conditioner for automotive vehicles comprises: a casing formed therein with an air inlet passage, a discharging air passage communicating the air inlet passage with an upper or face-level air outlet or a floor air outlet, a heating air passage extending from the air inlet passage to the inlet of a heater core, and a hot air passage extending from the outlet of the heater core and terminating at least in a side wall of the heater core where it intersects with the discharging air passage; a temperature adjusting damper for adjusting the ratio of air being supplied from the air inlet passage to the discharging air passage and air being supplied from the air inlet passage to the heating air passage; and an auxiliary damper arranged at the intersection of the air discharge passage with the hot air passage or in its vicinity for interrupting the communication between the latter two passages.

Abstract: An air-conditioning method and system for an automotive vehicle according to the present invention automatically maintains the temperature of air within the passenger compartment at a value preset by a passenger compartment air temperature presetting device and adjusted to a comfortable temperature which varies according to the outside-air temperature in accordance with a predetermined relationship defined by three linear functions having two points of intersection. The method comprises the steps of calculating a basic outlet duct air temperature, calculating an outlet duct air temperature correction, adding the two calculated values, and calculating an air mix door opening percentage, in addition to calculating a comfortable passenger compartment air temperature.

Abstract: An apparatus for controlling the air conditioning of a vehicle in accordance with the operational condition of said vehicle, the state of air conditioning of the passenger compartment of said vehicle and the relationships among the passenger compartment temperature, the atmospheric temperature and a command value of the passenger compartment temperature.

Abstract: An automatic temperature control system for a vehicle air conditioner including a cool air supply mechanism having an air flow control device, an air flow dividing device for dividing a cool air flow supplied from the cool air supply mechanism into a primary flow and a secondary flow, a heat source for heating the primary flow, and a mixing mechanism for mixing the primary flow as warmed past the heat source, and the secondary air which remains cool, with each other.

Abstract: An air conditioning system particularly mounted in a passenger compartment of an automotive vehicle according to the present invention can be fixed in the maximum heating operation mode to produce a maximum effect of the defrosting function by only pushing a push-button switch engaged with a mode selector for maximizing the air blowing rate of a ventilating fan and also engaged with a three-way vacuum switch for opening a vacuum power servomechanism to the air to fix an air mix door in the maximum heating position.

Abstract: A vehicle air conditioner control method and apparatus for automatically controlling the air conditioning of the compartment of a vehicle in accordance with a predetermined automatic control pattern, uses a selector for selecting a desired air conditioning condition. In response to the command signal from the selector, changeover from the control parameters, such as, air flow rate and supply air temperature for an automatic control mode to the selected control parameters for a selected air conditioning mode is effected, thus making it possible to selectively control the air conditioning of the vehicle compartment in accordance with a predetermined automatic control mode and a selected air conditioning mode.

Abstract: An air treatment assembly through which flows an air flow. The air flow is introduced into a ducting system, at an intermediate part of which a heater element is mounted. A first damper upstream of the heater divides the air flow into a first air flow portion passing through the heater and a second air flow portion bypassing the heater. First and second air outlets downstream of the heater element pass air out of the ducting system. A second damper, downstream of the heater element and upstream of the outlets, is movable between a first position in which it hinders the first and second air flows from mixing, so that the air passed out from the first outlet is primarily air from the first air flow, and the air passed out from the second outlet is primarily air from the second air flow; and a second position, in which it does not substantially hinder mixing of the first and second air flows, which meet downstream of the heater and mix well before being passed out from the air outlets.

Abstract: A vehicle mounted air conditioner controlling system is disclosed and of which system comprises a vacuum mode controlling switch (41) being controlled by depression of push-button switches (56) for each mode and mounted on a controller, a shift actuator (43) and vacuum selectors (42, 42'). The system is controlled by uni-directional vacuum signal and blower outlet doors and the air intake door are controlled by respective actuator provided individually therefor.

Abstract: A damper door unit is swingably disposed in an air intake duct for selectively permitting outdoor intake introduction and indoor air introduction. The damper door unit comprises a main door which is swingably connected to the air intake duct to selectively close an outdoor air intake opening and an indoor air intake opening, and an auxiliary door which is swingably connected to the main door to selectively close and open an opening formed in the main door. When of warming of the passenger compartment is required, the main door takes a position to achieve outdoor air introduction. However, under low speed cruising of the vehicle or at standstill of the vehicle with the engine idling, the auxiliary door opens to a certain extent thereby permitting a certain degree of indoor air introduction.

Abstract: An emergency controller for an air conditioning system of an automotive vehicle which incorporates an electronic control circuit in the automatic temperature adjusting means to perform a proportional control over an air mixing door by the use of a vacuum power servo is operated to connect a vacuum source to the vacuum power servo or to cause the air to flow into the vacuum power servo so that the maximum cooling or heating operation can be achieved. Consequently, when a trouble occurs in the electronic control circuit during running in a high-temperature region or low-temperature region, the air conditioning system may immediately be fixed in the maximum cooling or heating operation without intervention of electric circuits.

Abstract: Disclosed is a terminal unit for an air conditioning system. The apparatus has a common chamber for primary and secondary air and a throttling valve at the primary air duct connection controlled by a zone thermostat. The terminal unit fan is independently controlled by an air flow sensor located ahead of the throttling valve in order to prevent fan overload.

Abstract: An air conditioner of a vehicle having a selectively controlled conditioned air blowing outlet system using a shift actuator (20) equipped with a number of negative pressure supplying ports (a, b, c, d), in which selection of the operation mode of the conditioner is represented by the supply of a negative pressure signal to any one of the supplying ports, which causes displacement of a piston (31) of the shift actuator (20). The displacement is conveyed to selected one or more of doors provided at the outlets via a link mechanism to control the outlets according to a predetermined program.

Abstract: In an internal combustion engine air intake temperature control system a pivotal valve is movable between two extreme positions of angular movement to open one and close the other of a cold air inlet and a warm air inlet to an engine air intake passage, said valve being biased in a direction to close said cold air inlet, and a thermo-responsive device in said intake passage includes an actuator constructed so as, in response to increasing temperature in said intake passage, to engage said valve and move it against said bias to open said cold air inlet and close said warm air inlet, said valve also being movable to open said cold air inlet, against said bias, in response to a predetermined pressure differential across said valve, and said thermo-responsive device including a stop member constructed so that, when the temperature sensed by said thermo-responsive device is below a predetermined value, the stop member is positioned so as to prevent complete closure of said warm air inlet by said valve.

Abstract: An intake control system comprising a mode selector which receives a first control pressure and a second control pressure, and, according to the temperature inside and outside the vehicle, adapted to supply selectively a plurality of different combinations of the first and second control pressures to a pressure activated actuator to switch an air intake system between at least an outside air position and a recirculating air position. An air intake changeover switch receives the pressure output by an air control switch, a first reference pressure and a second reference pressure, and supplies a certain combination thereof as the first and second control pressures, when operated, to the mode selector, thereby causing the actuator to switch the air intake system to the recirculating air position, irrespective of the switching state of the mode selector.

Abstract: Air mixing apparatus that is particularly useful in connection with a winter make-up air and a summer ventilation system for a factory, warehouse or the like includes inner and outer relatively movable ducts, the former having side walls, an air inlet through which outside air can be drawn into the outer duct and an air outlet through which air can exit from the outer duct. At least one first port is provided in the side walls of the outer duct for passage of inside air, i.e, air from inside the building, into the outer duct. The inner duct has at least one second port in its side walls through which air can pass into the inner duct, and the inner duct also has an air outlet for passage of air into the outer duct where it can exit from the air outlet of the outer duct. Baffles extend between the inner and outer ducts on either side of the at least one first port and with the inner and outer ducts define a header. A motor or the like can move the ducts relative to each other between two positions.

Abstract: The present invention provides an air-handling unit that can supply air, to a desired space, which is cold, which is cooler than the set point of the thermostat for that space and hence is referred to as cool air, which is warmer than that set point and hence is referred to as warm air, or which is hot. That unit can operate even when very low pressure air is supplied to it; and hence it is connectable to a conventional low pressure cold air duct. That unit may have a heat source incorporated into it, may utilize air from that space which is cooler than that set point and hence can be referred as cool air, and may utilize air from the space which is warmer than that set point and hence can be referred to as warm air. Dampers in that unit control the amount of cold air and cold air that is supplied to that space, and a blower and the heat source in that unit control the amount of warm air and hot air which is supplied to that space.

Abstract: An air conditioner of an automatic temperature adjusting type used particularly for controlling the air temperature within a passenger compartment of an automotive vehicle. According to the present invention, the air conditioner controls simultaneously the air flow rate of a fan providing the air supply, and an air mixing door which controls the flow of air through either a heater or a bypass around the heater. The control is such that over an intermediate portion of the adjustment range the fan and air mixing door are operated together whereas at end portions of the adjustment range the fan is adjusted without moving the air mixing door. This is achieved by use of a particularly convenient gear mechanism of novel design.

Abstract: A vacuum regulator valve (10) is disclosed comprising a force-balance modulator valve subassembly (114, 118, 119, 122, 124, 126) mounted to a housing (12, 30) having inlet (14) and outlet (16) fluid ports. A vent insert (114) is adjustably biased through a biasing spring (166) by a rotary cam arrangement which includes a spring (64) biased rotary input member (48) rotatably mounted on a housing tubular projection (40). A ring-shaped drive member (144) is rotatable with input member (48) and supports a cup-shaped cam member (154). As projections (152) on the reaction member (144) rotate relative to cam surfaces (160), the cam follower is moved linealy relative to the vent insert. Locking tabs (50, 146, 148, 150) and alignment grooves (46, 80, 96, 98) enable the cam arrangement to be assembled in a predetermined angular position and locked to the housing without fasteners. An externally accessible adjustment member (162) enables valve calibration after final assembly.

Abstract: Air conditioning apparatus is disclosed. The apparatus is a terminal of the mixing type, receiving primary conditioned air, and delivering that air or a mixture including that air and recirculated air as required, for air conditioning. The rate at which primary conditioned air is delivered to the zone is varied between a maximum and a predetermined lesser rate as the air conditioning load on the space varies between a maximum and an intermediate load. The apparatus also includes a blower, nozzle or the like for inducing a flow of air from outside, and for mixing the induced air with primary conditioned air, so that such mixture is delivered to the zone. According to preferred embodiments which are disclosed, the apparatus is effective to deliver to the zone such a mixture of primary conditioned air and induced air under all conditions of air conditioning load on the zone.

Abstract: Air flows to the conditioned space through a cool air duct and a warm air duct which feed a common delivery duct. The inlet of the cool air duct is connected to a cool air supply duct of a parent system; and inlet of the warm air duct communicates with the return air plenum. Flow control components are air actuated and are controlled by actuators responding to a varying air pressure control signal, which is the output of a thermostat in the conditioned space producing a varying signal pressure signal related to varying temperatures. Dampers in the cool air duct and warm air duct provide for alternative air flow from either of these ducts to the delivery duct. The volume of air flow in the cool air duct is controlled by a modulating damper which responds to a selected signal pressure range. The air flow in the warm air duct is controlled by a fan and dampers, controlled through change of the signal pressure in either direction relative to a selected signal level.

Abstract: An apparatus for mixing high and low pressure air from a jet engine and introducing the air to an air duct of the air conditioning system of an aircraft. The apparatus provides a plurality of high pressure nozzles inside an air-mixing chamber. By controlling the opening and closing of the nozzles individually, a stepped area ratio of high pressure air with low pressure air is provided for regulating the temperature of the mixed air to the air conditioning system of the aircraft while the aircraft is taking-off, climbing, cruising at various altitudes and landing.

Abstract: An air induction unit having a first induction means to induce secondary air through a first induction opening into a stream of primary air to produce an air stream of mixed primary and secondary air, and a second induction means to induce additional secondary air into the mixed air stream through a second induction opening.

Abstract: An air cleaner of an internal combustion engine including an air inlet conduit connected to a main body containing a filter element and composed of upper and lower longitudinally extending conduit portions formed of a synthetic resin and connected together. The lower conduit portion is formed integrally with a heated air inlet port, and the upper conduit portion is formed integrally with a stepped flange for constituting a lower half portion of a housing of a vacuum motor. A cap is joined by supersonic melt adhesion or bonding to the stepped flange with an outer peripheral edge of a diaphragm being held therebetween, to provide an upper half portion of the housing of the vacuum motor. The diaphragm is connected at its upper portion to a valve body for opening and closing the heated air inlet port which is controlled by the vacuum motor of the diaphragm type.

Abstract: Disclosed is a temperature control apparatus for an air conditioner of an automobile. This temperature control apparatus comprises a push button switch for elevating the set temperature and a push button switch for lowering the set temperature.Every time the push button switch for elevating the set temperature is depressed, the set temperature can be elevated by, for example, 1.degree. C. On the other hand, every time the push button switch for lowering the set temperature is depressed, the set temperature can be lowered by, for example, 1.degree. C. Accordingly, the temperature can easily be set at an optional level by operating these switches appropriately. The so set temperature is digitally and visually displayed very clearly by a digital indicator.

Abstract: The damper system for controlling the flow of a gaseous fluid in a duct member is disclosed in which the combination of parallel and opposed flow characteristics is utilized to produce a composite rate of flow which varies substantially linearly with the angle of rotation of the damper blades over the full opening range. A plurality of damper blades pivotally mounted in substantially louvered fashion is utilized in one embodiment in which alternate pairs of blades are rotated in opposite directions to produce alternate parallel and opposed passage flow characteristics. In addition to being linear, the alternate parallel and opposed flow characteristics of the adjacent blade systems of the damper provide an additive advantage in mixing flow from different streams each being provided with one of the dampers. This can be produced by combining the alternate swirling and sheet flow of the damper openings in a manner which produces intermeshing of the flow and complete mixing of the two streams.

Abstract: A linkage connection for connecting a wax thermostat and membrane actuator drive assembly to a flapper-type flow proportioning valve in the air intake system of a carburetor-equipped internal combustion engine, the connection comprising a connecting cylinder formation in the flapper wall with a transverse slot and a groove in an extension of the thermostat housing with two positioning flanks which cooperate with the connecting cylinder.

Abstract: A regulator assembly for an automatic temperature control system for the passenger compartment of an automotive vehicle. Regulation is by vacuum signal modulated by a sensor responsive to the difference between a selected temperature and the temperature of air in the passenger compartment of the vehicle. A vacuum actuator operated by the modulated vacuum signal is provided for operating an air-blend door for controlling the passage of blower driven heated and cooled air into the passenger compartment. The regulator includes a compact removable vacuum signal modulator subassembly of a bimetal temperature sensing element directly coupled to a vacuum signal modulator valve. Direct feedback of the position of the vacuum actuator to the bimetal sensing element is provided. The modulator is of the type employing balancing of the pressure forces of the vacuum signal against the bias of the bimetal element for positioning the modulator valve.

Abstract: A thermostatic valve for compensating for the change in the intake air temperature of an internal combustion engine. The thermostatic valve has a temperature detector attached to a housing provided with a port in communication with atmosphere, a pipe in communication with a vacuum motor, a pipe in communication with the portion of the intake passage downstream from the throttle valve of carburetor and a pipe in communication with the float chamber of the carburetor and also with the air cleaner of the engine. A first valve element adapted to be operated by the temperature detector, and a second valve element adapted to be operated by the first valve element are disposed in the housing and are pressed against respective valve seats formed in the housing by means of springs. The introduction of vacuum in the intake passage into the vacuum motor for adjusting the intake air temperature is controlled in response to the change in the intake air temperature.

Abstract: A device for adjusting the intake air temperature of a carburetor-equipped internal combustion engine whose air intake system has a flapper valve in a duct junction admitting cold raw air and/or preheated raw air to the intake filter, depending on the raw air temperature, the flapper valve position being controlled by a pneumatic membrane actuator which receives negative pressure from the intake manifold, via a vacuum line with a thermostat-controlled relief valve responsive to the temperature of the air mixture. In the drive connection between the membrane actuator and the flapper is arranged a wax thermostat which increases or decreases the effective length of the connection in response to the ambient air temperature, thereby adding the thermostat displacements to the actuator displacements, the effective length of the drive connection being further adjustable by means of a threaded connection which is arranged between the membrane support body of the actuator and the wax thermostat.

Abstract: An apparatus for supplying conditioned air at a substantially constant temperature and humidity. The apparatus includes a supply duct coupled to a source of supply air for carrying the supply air therethrough. A return duct is coupled to the supply duct for carrying return conditioned air therethrough. A temperature reducing device is coupled to the supply duct for decreasing the temperature of the supply and return conditioned air. A by-pass duct is coupled to the supply duct for selectively directing portions of the supply and return conditioned air around the temperature reducing device. Another by-pass duct is coupled to the return duct for selectively directing portions of the return conditioned air around the supply duct and the temperature reducing device.

Abstract: An air cleaner temperature sensor for use in sensing the temperature of the air in an air cleaner and modulating the temperature of the air entering the air cleaner in response to the temperature in the air cleaner comprising a plastic body having an inlet adapted to be connected to a vacuum source and an outlet through which the vacuum can be connected to a motor for controlling the flow of air to the air cleaner. The body includes an opening to the ambient air surrounding the body, a valve in said opening and a bimetallic element is supported by the body and is operable to control the valve element such that the flow of air through the ambient air inlet is controlled by the bimetallic element, the body has a cover and an integral plastic hinge connecting the cover to the body. The cover has a portion thereof extending along the side wall of the body and an interengaging mechanical means between the cover and the body to lock the cover in position.

Abstract: The invention provides an air terminal capable of serving multiple zones with either variable volume, constant temperature air or variable temperature, constant volume air, or both, without any reheating of cold air. The terminal consists of a cold air plenum and a return air plenum. The cold air plenum is served with cold air from a primary cold duct. The air is introduced into this plenum through a damper which is controlled by a regulator for maintaining a constant pressure in the cold air plenum. The return air plenum is supplied with return air by a constant pressure recirculating fan mounted in the terminal. Constant volume, variable temperature air is supplied to the zones through thermostatically controlled mixing dampers which mix air from the cold plenum with air from the return plenum. A heating unit downstream from the mixing dampers selectively raises the temperature of the air provided to a zone.

Abstract: A mixed air conditioning controller is formed as a factory assembled and adjusted unit in a compact housing, with simple and direct input/output field connectors. Various temperature and humidity input devices are field connected to produce a sequenced control of the air dampers and mechanical cooling and heating devices, as well as auxiliary devices. The controller includes a primary input related to room demand, an outside air temperature input, with an interlocked control to the damper, a fan status input, a minimum air supply control and a by-pass switch having a low limit input. The logic network connecting the input/output includes pneumatic switching, pressure selecting and comparing devices of a diaphragm-controlled-orifice construction connected to function as fluidic repeaters, pressure regulating valves and pressure isolating and switching devices. The controller includes a conditioning channel and a damper channel.

Abstract: Two fluid streams of different temperatures flow through two concentric pipes, the flow of each stream being modulated to achieve a desired mixture temperature. An in-line slide valve is interposed in one fluid flow path, and an in-line poppet valve is interposed in the other fluid flow path. A thermally responsive element is positioned downstream to sense the temperature of the mixed fluid stream, the element being connected via a rod to both the slide valve and the poppet. When the mixture temperature varies from a preselected temperature, the thermally responsive element moves the rod to gradually close the slide valve and open the poppet, or gradually close the poppet and open the slide valve, thereby changing the flow of both fluid streams and maintaining the desired mixture temperature.

Abstract: Upon sensing an excessive temperature in a plenum supplying secondary air to a mixing box, a thermostatic element opens a valve to exhaust air from a pneumatic actuator for opening a normally closed secondary air damper. This action permits the damper to close and so prevent flow of secondary air from the plenum into the mixing box. The control may be tested by applying auxiliary heat to the thermostatic element. The control may be made to prevent spread of smoke by making the application of heat to the thermostatic element responsive to a smoke detector.

Abstract: An economizer system for air conditioning uses a space thermostat to determine a demand for cooling and an outside air controller to determine whether cooling shall be mechanical or natural. A mixed air controller senses the temperature of the mixture of outside air and recirculated air and adjusts the relative proportions as desired by means of a controlled bidirectional damper, moving at a rate far less than the response time of the mixed air controller. This slow bidirectional damper movement in response to the mixed air control sensors causes the dampers to modulate in an inexpensive and reliable manner.

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 air discharge terminal unit comprises a plenum housing having a main air inlet, a main air outlet and an induced air inlet, the induced air inlet being located unilaterally along the flow path of the air between the main air inlet and the main air outlet to control the flow of air from the main air oulet.

Abstract: A control for an induction air mixing box for mixing conditioned primary air and induced secondary air for delivery at a substantially constant volume rate of flow into a condition controlled space, the volume rate of flow of primary air being maintained constant at a predetermined rate, said predetermined rate being resettable as a function of the sensed condition in the space. The induced rate of flow of secondary air is restricted as another function of the sensed condition, the change in rate of flow of the secondary air being inverse to that of the primary air.

Abstract: A device for adjusting the intake air temperature of carburetor-equipped internal combustion engines having an air intake system with a flapper valve in a duct junction admitting cold raw air and/or preheated raw air to the intake filter, depending on the raw air temperatures, the flapper valve position being controlled by a pneumatic membrane actuator receiving negative pressure from the intake manifold, via a vacuum line with a thermostat-controlled relief valve responsive to the temperature of the air mixture. In the drive connection between the membrane actuator and the flapper is arranged a wax thermostat which increases or decreases the effective length of the connection in response to the ambient air temperature, thereby adding the thermostat displacements to the actuator displacements.

Abstract: An output member of the present actuator is connected to control a temperature door in an air conditioning duct leading into an automobile passenger compartment and thereby the temperature in the compartment. The output member is connected to and moved by a diaphragm which is positioned by opposing forces of a diaphragm spring and modulated intake manifold vacuum. A valve is controlled by first and second bimetal springs which act in parallel against a feedback spring connected between the valve and the diaphragm. The first bimetal spring is responsive to air temperature in the compartment. The second bimetal spring is responsive to air temperature in the duct and compensates for variations in the operation of the air conditioning system caused by variations in load and the like.

Abstract: A heating and air conditioning system and a special variable volume terminal box associated therewith, the system utilizing energy dissipated by the lighting and other building facilities in a controlled manner through the functioning of the variable volume terminal box.

Abstract: An air conditioning system for conditioning the air in a plurality of enclosed areas in a building. Conditioned air at a temperature level which may be varied is supplied to a first terminal for discharge into an area. Conditioned air at a relatively constant temperature level is delivered to a second terminal for discharge into the area. The quantity of constant temperature air discharged into the area is regulated in accordance with the temperature level therein. The quantity of the variable temperature air stream discharged into the area is regulated in accordance with the quantity of constant temperature air discharged into the area.

Abstract: A primary fluid nozzle induces secondary fluid flow through an induction port opening. A damper valve element is provided at the induction port and is constantly biased open. A variable flow fluid inlet is positioned to one side of the nozzle orifice and arranged to direct fluid against the induction port damper tending to close the damper depending upon the flow of fluid through the variable flow fluid inlet. Thus, when primary fluid flow increases through the variable flow inlet, the secondary fluid damper tends to be closed, reducing secondary fluid flow.