Abstract: A thermal switch includes a thermally responsive plate assembly including a metal support deforming from an initial shape before a header plate assembly is secured to a housing assembly, with a result that a position of a movable contact in the housing assembly is adjusted so as to be within a predetermined height range relative to an open end of a housing. A contact pressure of switching contacts after the assembling is produced by the height adjustment, and subsequently, a neighborhood of a part of the housing to which part the thermally responsive plate assembly is secured is deformed, so that an operating temperature is calibratable.

Abstract: A thermal switch includes a thermally responsive plate assembly including a metal support deforming from an initial shape before a header plate assembly is secured to a housing assembly, with a result that a position of a movable contact in the housing assembly is adjusted so as to be within a predetermined height range relative to an open end of a housing. A contact pressure of switching contacts after the assembling is produced by the height adjustment, and subsequently, a neighborhood of a part of the housing to which part the thermally responsive plate assembly is secured is deformed, so that an operating temperature is calibratable.

Abstract: A thermally responsive switch includes a hermetic container including a housing and a header plate hermetically secured to an open end of the housing, a conductive terminal pin inserted through the header plate, a conductive pin, a thermally responsive plate having one of two ends fixed to the terminal pin, a movable contact secured to the other end of the thermally responsive plate, and a fixed contact fixed via an electrical conductor to the terminal pin, the conductor having a fuse part and a heater. The fixed contact is fixed to a ceramic member disposed between the container and the fixed contact. The housing includes a bottom surface including both lengthwise ends between which the conductive pin is interposed. Both ends of the housing bottom surface are deformed axially relative to the conductive pin from an initial state, so that an operating temperature of the switch is calibratable.

Abstract: A protector for a three-phase electric motor has a container with a housing and a metal plate secured thereto. A protrusion is provided in the housing. Three conductive terminal pins, each with a fixed contact, protrude into the housing through the metal plate. A thermally responsive plate is connected to the three moveable contacts. The thermally responsive plate is dish shaped and reverses its direction of curvature at a predetermined temperature. Three moveable contacts are secured to the thermally responsive plate. An elastic member extends between the protrusion and the thermally responsive plate. A rotation member prevents the thermally responsive plate from rotating, thereby maintaining the moveable contacts in opposition to the fixed contacts. The conductive terminal pins are located at a neutral point side of phase windings of a three-phase motor so that AC current flowing into the three-phase motor is interrupted.

Abstract: A sealed electric compressor having a normally-off type pressure switch and a fuse element. The pressure switch is placed in a sealed housing, connected parallel to a main winding of an electric motor, and, when the pressure of refrigerant in the sealed housing is abnormally high, activates to short-circuit the main winding. The fuse element is connected in series to the main winding and an auxiliary winding of the electric motor and interrupts conduction of electricity to the electric motor when an excess current that is produced when the pressure switch short-circuits the main winding flows.

Abstract: A protector for a three-phase electric motor has a container with a housing and a metal plate secured thereto. A protrusion is provided in the housing. Three conductive terminal pins, each with a fixed contact, protrude into the housing through the metal plate. A thermally responsive plate is connected to the three moveable contacts. The thermally responsive plate is dish shaped and reverses its direction of curvature at a predetermined temperature. Three moveable contacts are secured to the thermally responsive plate. An elastic member extends between the protrusion and the thermally responsive plate. A rotation member prevents the thermally responsive plate from rotating, thereby maintaining the moveable contacts in opposition to the fixed contacts. The conductive terminal pins are located at a neutral point side of phase windings of a three-phase motor so that AC current flowing into the three-phase motor is interrupted.

Abstract: A thermally responsive switch includes a movable contact fixed to an end of a thermally responsive plate and a fixed contact which is conductively connected with a conductive pin through a conductor having a fuse part and a heater part to constitute a pair of switching contacts with the movable contact. The thermally responsive switch is used for disconnecting an AC current flowing to a motor inside a sealed electric compressor. The fixed contact is fixed to an electrically insulating ceramic member disposed between the fixed contact and a sealing container.

Abstract: A sealed electric compressor having a normally-off type pressure switch and a fuse element. The pressure switch is placed in a sealed housing, connected parallel to a main winding of an electric motor, and, when the pressure of refrigerant in the sealed housing is abnormally high, activates to short-circuit the main winding. The fuse element is connected in series to the main winding and an auxiliary winding of the electric motor and interrupts conduction of electricity to the electric motor when an excess current that is produced when the pressure switch short-circuits the main winding flows.

Abstract: A thermal protector includes a header plate and a metal housing having an open end hermetically welded to an peripheral edge of the header plate. The housing is formed into a generally slender shape so as to be suited for mounting on end turns of a stator winding of a three-phase electric motor. A thermally responsive element includes a shallow curved portion at which the element changes states of curvature with snap action in response to different ambient temperatures. The thermally responsive element has two movable contacts secured to it to be disposed symmetrically about a center of the curved portion so that the movable contacts are engageable with and disengageable from fixed contacts respectively. A push piece is disposed in the housing to exert a pushing force on a normally convex side of the thermally responsive element. The pushing force is adjusted by deforming the outer surface portion of the housing for calibration of the operating temperature.

Abstract: A thermal protector for a hermetic electrically-driven compressor includes a thermal switch and a cluster socket. The protector is mounted inside a compressor housing on a terminal assembly mounted in a wall of the compressor housing. A casing of the thermal switch and a header plate hermetically closing an open end of the casing integrally form a flange on the peripheral edges when the header plate is secured to the casing. The thermal switch has two terminals one of which is provided with a receptacle into which one of terminal pins of the terminal assembly is fitted, and the other terminal is connected to a common lead wire of a compressor motor. The cluster socket has a plurality of terminal cavities for connecting windings of the motor to the terminal assembly. A body of the socket has a face having a pair of holding portions for holding the flange. Each holding portion has a hook-shaped portion at an end.

Abstract: A thermal protector for a hermetic electrically-driven compressor including a hermetically sealed housing in which a power-supply terminal, an electric motor and a compressor are enclosed with a predetermined amount of refrigerant gas is disclosed. The thermal protector includes a thermally responsive switch having first and second lead terminal pins for securing first and second connecting terminals respectively and a holder formed from an electrically insulating material and including first, second and third cavities. Each of the first and second cavities has an opening in its one side. The first cavity accommodates the thermally responsive switch while the second cavity accommodates a secured portion between the lead terminal and the connecting terminal with a hardenable electrically insulating filler filling up the second cavity. Alternatively, the second connecting terminal is secured to a wall of the holder by an insert molding so as to extend through the wall, instead of use of the filler.

Abstract: A thermally responsive switch for protecting electric motors against overcurrent and overheating conditions includes a metallic receptacle having an elongated dome-shaped portion and an opening opposite to the dome-shaped portion, a metallic header plate secured to the one end of the receptacle so as to hermetically close the opening afterwards and having a through-aperture, a thermally responsive element disposed in the receptacle in parallel with the header plate and carrying a movable contact at one end, a rod terminal secured in the aperture of the header plate by an electrically insulating material filled in the aperture for hermetic sealing so that the terminal extends through the aperture, a fixed contact support disposed in the receptacle to be perpendicular to the terminal and having an end to which a fixed contact is secured, the support being connected at the other end to the end of the terminal projected into the receptacle, by solder, and a spring for urging the support so that it is disconnected

Abstract: A three-phase thermal protector includes a hermetic receptacle composed of an elliptic dome-shaped cover having an opening at one end and a header plate having two terminal pins extending through respective apertures formed in it, and a switch assembly mounted in the receptacle. Two fixed contacts are secured to the respective terminal pins. The switch assembly includes a metal operating temperature calibrating plate with one end welded to the cover, a bimetallic thermally responsive element having one end secured to the calibrating plate and the other end having a central dish-shaped portion, and a thermally-responsive-element support to which the supported end of the thermally responsive element is welded. The thermally responsive element carries two movable contacts symmetrical about the center line.

Abstract: A thermally responsive switch includes an elliptic dome-shaped metal receptacle, a header metal plate hermetically secured to the receptacle and having a through-aperture at one of two longitudinal ends, an electrical conductor inserted through the aperture of the header plate and secured with an electrically insulating material such as glass, a support having at one of two longitudinal ends a fixed portion secured to the end of the conductor in the receptacle and a supporting portion positioned away from its other end in the direction of the fixed portion, a bimetal secured at one of its two ends to the supporting portion of the support and carrying a movable contact at the other end, the bimetal having a central shallow dish-shaped portion reversing its curvature with a snap action in response to the temperature, a fixed contact secured to the header plate in the vicinity of its other longitudinal end, and a calibrator interposed between the inner wall of the receptacle and the other end of the support oppo