Abstract: A thermally actuated device, such as an electrical circuit breaker (10) is provided with an ambient temperature compensation thermostat metal member (38) selected so that it bends when subjected to changes in temperature and compensates for ambient temperature effects on a thermostat metal trip arm for a selected current rating. Movement of such thermostat metal member is directly proportional to the flexivity of the material and to the square of the length of the member and indirectly proportional to the thickness of the member. Since packaging constraints make changes in length impractical, compensation members used to provide temperature compensation for different current ratings of the device typically have been made by using members of different thickness.

Abstract: A pushbutton resettable circuit breaker is shown having features to prevent manual opening by simply pulling outwardly on the pushbutton. In one embodiment, the pushbutton (16) is formed with slots (16b) which are configured to provide a reaction surface essentially inaccessible without a special purpose contact opening tool (30). The tool is provided with portions that are insertable into the slots and into engagement with the reaction surfaces for pulling the pushbutton out and manually opening the contacts. In a second embodiment, a small aperture 16k is formed through the rating tab and top and wall of the button and in alignment with a movable plunger (28). A special purpose contact opening tool (32, 34) can be inserted through the aperture to apply a force to the plunger and mechanically trip the circuit breaker.

Abstract: A circuit breaker (10) has a current carrying bimetallic element (18) which bends upon self-heating and upon being subjected to a selected overload current transfers motion to a connecting plate (32) which displaces a latch surface (42b) from a catch (34a) of a bell crank mechanism (34) allowing a spring biased operating member (28) to move movable contact means (12) out of contact engagement with stationary contact means (14) thereby tripping the circuit breaker. An arc sensing circuit (52) is coupled to the load circuit and upon sensing selected arcs causes an arc responsive actuator (56, 62) to be energized to transfer motion to the latch (42) to trip the circuit breaker.

Abstract: A circuit breaker (10) has a current carrying bimetallic element (18) which bends upon self-heating and upon being subjected to a selected overload current transfers motion to a connecting plate (32) which displaces a latch surface (42b) from a catch (34a) of a bell crank mechanism (34) allowing a spring biased operating member (28) to move movable contact means (12) out of contact engagement with stationary contact means (14) thereby tripping the circuit breaker. An arc sensing circuit (52) is coupled to the load circuit and upon sensing selected arcs causes an arc responsive actuator (56, 62) to be energized to transfer motion to the latch (42) to trip the circuit breaker.

Abstract: A circuit breaker (10) is shown having a movable electrical contact (36) adapted to move into and out of engagement with a stationary electrical contact (38, 40). A current carrying thermostatic trip member (42) has a portion movable in response to changes in temperature with a motion transfer member (46) transferring the motion to latch/catch mechanism (20, 24, 30, 32). The catch portion (30, 32) comprises a generally U-shaped adjustment element (30) formed of thermostatic material whose legs are fixed to the base (32a) of a catch member (32) which in turn is pivotably mounted in the casing of the circuit breaker. The bight (30c) of the adjustment element is free to move in response to temperature changes relative to the catch member. Overcurrent will cause the thermostatic trip member to transfer motion to the bight of the adjustment element causing the adjustment element and catch member to pivot and release a latch to thereby open the circuit breaker.

Abstract: A switching element (40, 40′) for use in a snap-acting electrical switch (10) has a pair of outer legs (40a, 40b; 40a′, 40b′) and a center leg (40c) extending in substantially the same direction from a junction portion. The outer legs have a semi-annular band portion which blend together at the junction portion and a center leg at one end of the band portion. A mounting portion extends from the other end of the semi-annular band portion and is provided with mounting apertures (40k, 40l) for placement on mounting posts (18, 20) in a warped, stressed condition. A strengthening portion (40n, 40r) is formed in each semi-annular band portion, preferably along the outer portion thereof, i.e., the outer portion being away from the junction portion. An electrical contact (32) is mounted on the distal free end of the center leg for snap-movement between a pair of stationary electrical contacts (28b, 30b).

Abstract: A heater for heating fluid is shown having a plurality of self-regulating electrical resistance heater elements 22 placed in electrically and thermally conductive relationship with heat transfer members 20, 120. The heat transfer members are each configured to form a plurality of fluid receiving channels so that when placed in a fluid stream heat generated by the heater elements will be dissipated to the fluid through the heat transfer members. Additionally, thermally conductive grease is used between the heater elements 22 and heat transfer member 20, 120 to better transfer the heat. The heater elements are arranged in groups with at least two heater elements in a group electrically connected in series and the groups electrically connected in parallel.

Abstract: A heater particularly adapted for use in automotive applications as a passenger compartment heater or the like has a housing with an opening and has a plurality of heat-exchanging fin members and self-regulating electrical resistance heater discs of positive temperature coefficient resistivity (PTC) disposed in the housing to heat air or other fluid which is passed through the housing opening in heat-transfer relation to the fin members. A thermally conductive grease is positioned between the PTC heater discs and fin members to enhance heat transfer. Springs resiliently position the fin members, grease and heater discs in thermally and electrically conductive relation to each other between terminals accessible from the housing exterior to retain the fin members, grease and heater discs engaged during thermal expansion and vibration for reliably energizing the heater discs to heat the fin members over a long service life.

Abstract: A system for heating the passenger compartment of an automotive vehicle has a hot water heater receiving heat from a vehicle engine arranged in series with a self-regulating electrical resistance heater of positive temperature coefficient of resistivity, has a power source for energizing the electrical resistance heater, and has a fan for directing air in heat-transfer relation to the hot water heater and to the electrical resistance heater in sequence to provide a heated air output to the passenger compartment. Fan speed is controlled to regulate the volume of air directed in heat-transfer relation to the heaters so that the electrical resistance heater is promptly and consistently capable of heating that volume of air to at least a selected minimum temperature such as 100.degree. F. as the heated air output is furnished to the passenger compartment, thereby to give a vehicle passenger an immediate and continuing sensation of comfort beginning very promptly after engine start-up even on a very cold day.

Abstract: A supplementary heating system particularly suitable for an automotive vehicle comprises a step down transformer coupled to the stator windings of the vehicle's alternator and a positive temperature coefficient (PTC) of resistivity heater electrically connected intermediate the stator windings and the transformer in parallel with the transformer. Due to the presence of the transformer the voltage regulator causes the alternator to operate at a higher than customary voltage to provide the conventional 14.4 volts for the vehicle's normal electrical loads with the high voltage used to energize the heater. The heater can be in the form of a so-called "honeycomb" having a plurality of parallely extending passages or cells disposed in the air stream going from the main heater into the passenger compartment and can be either a multiphase, single phase or direct current type.

Abstract: A pressure transducer having a capactive pressure sensing moudle disposed in a housing is biased against a sealing ring disposed in a chamber circumscribing a fluid pressure inlet by a retainer ring mounted in the housing. A selected back-up washer may be used to accommodate various size pressure sensing modules. The housing is sealed from the environs by means of a hermetic glass-to-metal header which mounts terminals to provide electrical coupling to electronics mounted in the housing.

Abstract: An automatic alternator is coupled to both a step up and a step down transformer. The outputs from the transformer are rectified and connected respectively to a windshield heater and to a circuit comprising the normal 14 volt car loads and the battery. A switch is coupled to the output of the step up transformer to control the energization of the windshield heater. Output leads from the alternator also bypass the transformer and are rectified with its DC output connected through switched to a positive temperature coefficient of resistivity heater and to the normal car load circuit.

Abstract: A supplementary heating system particularly suitable for an automotive vehicle comprises a step down transformer coupled to the stator windings of the vehicle's alternator and a positive temperature coefficient (PTC) of resistivity heater electrically connected intermediate the stator windings and the transformer in parallel with the transformer. Due to the presence of the transformer the voltage regulator causes the alternator to operate at a higher than customary voltage to provide the conventional 14.4 volts for the vehicle's normal electrical loads with the high voltage used to energize the heater. The heater can be in the form of a so-called "honeycomb" having a plurality of parallely extending passages or cells disposed in the air stream going from the main heater into the passenger compartment and can be either a multiphase, single phase or direct current type.

Abstract: A cover for an automotive vapor canister has a heat-spreading member heated by a self-regulating electrical resistance heater of positive temperature coefficient of resistivity for heating air which is periodically introduced into the canister for purging the canister. The cover has a first cover of thermally insulating material defining a thin inner air flow path section to pass air being introduced into the canister over the heat-spreading member for transferring heat to the air and to receive additional heat within the first cover and has a second cover of thermally insulating material defining a thin outer air flow path section overlying and connected with the inner air flow path section to pass the air over the first cover prior to being advanced into the inner flow path section for withdrawing said additional heat from the first cover to preheat the air and improve air heating efficiency.

Abstract: A cover for an automotive vapor canister has a heat-spreading member heated by a self-regulating electrical resistance heater of positive temperature coefficient of resistivity for heating air which is periodically introduced into the canister for purging the canister. The cover has a first cover means of thermally insulating material defining a thin inner air flow path section to pass air being introduced into the canister over the heat-spreading member for transferring heat to the air and to receive additional heat within the first cover means and has a second cover means of thermally insulating material defining a thin outer air flow path section overlying and connected with the inner air flow path section to pass the air over the first cover means prior to being advanced into the inner flow path section for withdrawing said additional heat from the first cover means to preheat the air and improve air heating efficiency.

Abstract: A resistor particularly useful as a multiphase, self-regulating fluid heater has passages extending through a body of ceramic resistance material of positive temperature coefficient of resistivity (PTC) for heating fluid adapted to pass therethrough. Several embodiments are provided with electrically conductive coatings formed on inner walls of the passages with the passage walls defining thin webs of the resistance material having uniform thickness from end to end. The passages are arranged in a plurality of sets with the conductive coating on the walls of the passages of each set interconnected and adapted for electrical connection with a respective electrical phase. The passages of the sets are alternated relative to one another throughout the body with a passage of one set immediately adjacent only to passages of other sets. The passages are configured in different embodiments including hexagonal, triangular and rectangular as seen in plan view showing one end of the body.

Abstract: A supplementary heating system particularly suitable for an automotive vehicle comprises a step down transformer coupled to the stator windings of the vehicle's alternator and a positive temperature coefficient (PTC) of resistivity heater electrically connected intermediate the stator windings and the transformer in parallel with the transformer. Due to the presence of the transformer the voltage regulator causes the alternator to operate at a higher than customary voltage to provide the conventional 14.4 volts for the vehicle's normal electrical loads with the high voltage used to energize the heater. The heater can be in the form of a so-called "honeycomb" having a plurality of parallely extending passages or cells disposed in the air stream going from the main heater into the passenger compartment and can be either a multiphase, single phase or direct current type.

Abstract: A body comprising a ceramic electrical resistance material of positive temperature coefficient of resistivity adapted to display a sharp increase in resistivity when heated to a selected temperature has passages extending through the body between opposite ends of the body for passing fluid through the passages in heat-exchange relationship to the body and has means electrically contacting spaced-apart portions of the body for directing electrical current through the body to self-heat the body. The body is made with an improved structure in an improved manner and is particularly adapted for use as a self-regulated fluid heater within a small or irregularly-shaped conduit or the like.

Abstract: A fuel system for an internal combustion engine has an electrical resistance heater accommodated in low profile gasket means at a location between a throttle body mounting flange and a mating intake manifold flange for heating the throttle body. The gasket means comprises a relatively rigid electrically insulating spacer forming a chamber, a heat-transfer member and a terminal secured to opposite sides of a heater for mounting and making electrical connection to the heater which is accommodated in the spacer chamber, and relatively thin outer layers of more compressible gasket material for sealingly engaging the throttle body and mating manifold flange means respectively.

Abstract: A fuel system for an internal combustion engine has an electrical resistance heater accommodated in gasket means disposed between a throttle body flange and a mating flange on an intake manifold so that the heater is located immediately adjacent an idling speed fuel inlet nozzle or the like in the throttle body for transferring heat to the nozzle area through the throttle body flange to prevent freeze-up of the nozzle during engine operation.