Abstract: An exhaust pressure maintenance system and apparatus for an engine exhaust system which imposes a scheduled back pressure on the engine independently of restrictions in the exhaust lines downstream from a pressure controller valve. The back pressure which is maintained is purposely lower at low flow rates than at high flow rates, so that the engine power is not unnecessarily diminished under these conditions.

Abstract: A moisture indicator particularly adapted for use in a refrigerant system to indicate by visual inspection the moisture content of refrigerant therein. A preferred embodiment of the indicator comprises a hygroscopic plastic sleeve which is mounted behind a sight glass within a housing such as a receiver. The whole sleeve can be impregnated with a cobalt salt whose color changes when exposed to water. In use, the color of the indicator may be visually compared with a reference color stripe which does not change color with the addition of moisture and which is preferably applied adjacent the cobalt salt. The sleeve can also be non-hygroscopic plastic, or even metal, coated with a thin film of hygroscopic plastic containing cobalt salts.

Abstract: An improved "reset" type odometer assembly having counting wheels rotatably supported on a shaft and interconnected by pinion gears therebetween for sequential counting as mileage progresses. A gear wheel between each of the counting wheels is engaged on its right side by a pinion gear which moves with each revolution of the counting wheel located to its right. In turn the gear wheel engages an outer pawl on a molded ratchet spring to cause corresponding rotation of the leftwardly positioned counting wheel. The ratchet spring also has an inner pawl which is engaged by a groove in the shaft when rotated to cause the ratchet spring and counting wheel to rotate during a reset mode of operation. During resetting, the gear wheel and pinion gears are stationary and the outer pawl moves between circumferentially spaced detents in the gear wheel.

Abstract: A thermostatically responsive valve for controlling fluid, including a thermally responsive power member for operating the valve and indicator means movable to an operative position indicative of an overheat condition in response to high fluid temperatures. Latch means are provided to prevent movement of the indicator means into the overheat position during an overheat condition when activated by the thermally responsive power member, so that the responsibility of the thermostat can be determined by examination.

Abstract: In a regenerative type gas turbine application, a mounting apparatus for a recuperator to support the recuperator between the relatively stationary end walls of a gas turbine housing while simultaneously permitting movement of the recuperator in plural directions with respect to the walls caused by thermal expansion.

Abstract: A refrigerant control valve for an air conditioning system in which a flow passage is formed between closely spaced poles of an electro-magnet which may be selectively magnetized by energizing a coil to produce a magnetic field through the pole members and across the flow passage. This attracts a quantity of small iron particles which are mixed with and circulate with the refrigerant and lubricating oil. The accumulation of iron particles on the surfaces of the pole members decreases the flow area between the poles and controls refrigerant flow.

Abstract: A thermally responsive freeze type actuator for operating an air conditioning throttle valve. The actuator includes a rigid walled tubular portion which contains water and is attached to an axially extendable and contractible bellows portion. The bellows portion contains an immiscible fluid such as oil which floats on the water. The pressure forces created by the formation of ice in the tubular portion is transmitted to the oil by compression of one end of a hollow bladder member made of flexible material such as rubber which extends axially through the tubular portion and the bellows portion.

Abstract: A piston type compressor for use in an automotive air conditioning system with variable pumping or compressing capacity which is automatically modulated in response to operating conditions. Compressor improvements are solely to the piston so that the present investment in fixed displacement compressors is not diminished. Previous compressors may be modified by the substitution of the improved pistons to create a variable capacity compressor. Specifically, the piston modifications include a pressure responsive displacement means on the piston end which extends into the compression chamber during portions of the intake stroke and compression stroke to effectively decrease the volumetric pumping capacity of the compressor whenever a predetermined low pressure is sensed.

Abstract: For use with an air outlet assembly having a damper valve therein with a crank arm extending from the side of the outlet, a combination lever and positioning spring adapted to engage the crank arm and pivot between first and second operative positions corresponding to open and closed positions of the damper. One end portion of the combination lever and spring which engages the crank arm has a bifurcated configuration with integrally jointed strip portions extending on either side of the crank arm. The lever is pivotally supported at a mid-portion and has a second end adapted for manual actuation. The bifurcated end portion forms an opening between the integrally joined strips through which the crank arm extends.

Abstract: A fluid control valve for a fluid system, such as an air conditioning system, in which a flow passage is defined by a radially flexible tubular member so that the flow area of the valve therethrough is variable. The tubular member and an encircling magnetic field producing means define an annular space therebetween containing a plurality of small iron particles which are attracted to an intermediate portion of the annular space when a magnetic field is produced, thereby causing inward movement of the flexible tubular member to decrease the valve's flow area.

Abstract: An improved thermally responsive freeze actuator for operation of an air conditioning throttle valve between the evaporator and compressor to maintain the pressure and temperature of evaporator refrigerant above a freezing level. The improved actuator includes a rigid-walled tubular portion containing water and an attached axially extendable bellows portion. The water in the tubular portion is separated from the bellows portion by a deep cup shaped member or diaphragm of elastomeric material. The deep pocket of the diaphragm encloses one end of a push rod. As the water surrounding the pocket portion of the diaphragm changes to ice the rod is moved axially from the tubular portion. The other end of the rod engages the bellows which may be stationary mounted to a frame member to cause the entire actuator to move with respect to a valve seat.

Abstract: A refrigerant control valve for an air conditioning system including a flow passage formed by a tubular member of non-magnetizable material encircled by an annularly shaped electromagnetic coil. The electromagnet is housed in a shell having an inner cylindrical wall located adjacent the tubular member and which extends from one end of the shell toward the second end and terminating therebetween to form an end surface. The second end of the housing shell has a threaded opening which encircles the tubular member and into which a calibration nut or member extends. The calibration member has an end surface which is spaced closely from the end surface of the cylindrical wall by rotation of the calibration member to produce a desired magnetic field therebetween when the electromagnetic coil is energized.

Abstract: An odometer assembly having a shaft on which a plurality of numbered counting wheels are mounted for rotation and including a rotatable service indicator wheel supported on the shaft next to the highest order counting wheel for rotation therewith until a flag portion which overlays the indicator wheel becomes visible to the vehicle operator. A drive mechanism between the service indicator wheel and the highest order counting wheel couples the wheels together for the aforementioned rotation and thereafter permits the highest order counting wheel to rotate with respect to the service indicator wheel. A rotatable reset lever means is also provided to counter-rotate the service indicator wheel back to its original non-indicating position.

Abstract: A low profile two-bed catalytic converter including substantially identical top and bottom housing plates and top and bottom catalyst-retaining plates therebetween which define an inclined catalyst-containing space. A plurality of openings in the retaining plates distribute exhaust flow uniformly through the catalyst-containing space. A partition made up of two spaced plates has a plurality of uniformly distributed exhaust flow apertures therein and extends through the catalyst-containing space to divide the space into upper and lower catalyst beds. An air distribution means between the partition plates has outlet nozzles for discharging air laterally into streams of exhaust gas flowing through apertures in the air distribution means as the exhaust gases pass from the upper to the lower catalyst bed.

Abstract: A piloted refrigerant valve for an air conditioning system to control refrigerant pressure within an evaporator to prevent frost accumulation on its exterior surfaces. The valve includes a disc-shaped hollow thermal sensor filled with water which solidifies and expands upon sensing the freezing temperature to cause a pilot valve to block a bleed port and thereby increase the fluid pressure above a reciprocally mounted piston valve. The pressure force produced on the piston valve moves it to a closed position to block refrigerant flow and resultantly to increase refrigerant pressure and temperature in the evaporator. After an initial start-up period of operation, the sensor maintains a position which locates the reciprocal piston valve so as to produce a substantially constant non-freezing temperature of refrigerant in the evaporator.

Abstract: A refrigerant control valve for air conditioning systems of the hot gas bypass type including a bypass passage between the compressor outlet and the evaporator inlet through which refrigerant flow is regulated by a pressure operated valve member one side of which is exposed to compressor outlet pressure and the other side of which is exposed to refrigerant pressure in a control chamber. The control chamber is connected by a bleed passage to the compressor inlet and a Schrader-type bleed valve therein to allow the discharge of refrigerant from the control chamber when open so that an opening pressure differential is established across the valve when the bleed valve is open. A sensor-actuator for the bleed valve is supported near the evaporator outlet in the refrigerant flow therefrom and includes a housing with a rigid wall and a movable wall which encloses an interior space filled with water.

Abstract: A humidity-biased temperature responsive switch for controlling an automobile air conditioning compressor which closes at a warmer ambient temperature when the humidity is low than when the humidity is greater. The switch includes a sensor element having a metal strip and a hygroscopic plastic strip laminated together so that the different thermal coefficients of expansion will cause the free end of a cantilever-mounted sensor to move a contact. Absorption of water from the ambient air causes the plastic to swell and elongate and resultantly moves the contact into a closed position at a lower temperature than when the humidity is low.

Abstract: A vehicle cooling system utilizing a remotely located radiator and cooling fan permitting the vehicle engine to be enclosed by insulating material for reducing noise. The radiator in the preferred embodiment illustrated is mounted horizontally in an air passage formed partially by the passenger compartment roof. A fan is located below the radiator for drawing air therethrough when the vehicle is idling. The fan is powered by a hydraulic motor which receives pressurized coolant from the engine water pump.

Abstract: A combination high pressure relief valve and magnetic clutch disconnect switch for an air conditioning compressor which utilizes an automatically resetting valve member. The escape of pressurized refrigerant under control of the relief valve pressurizes the interior of a cap member on the end of the relief valve and thereby disconnects the ground circuit portion of the electromagnetic compressor clutch. This renders the system inoperative until the cap can be replaced and the original cause of the high pressure is determined and remedied.