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 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

Abstract: A thermal motor protector includes a cylindrical metal housing having an open end and a bimetal disposed in the housing so that its one side is opposite to an housing inner bottom. The bimetal has a shallow dish-shaped portion so that it inverts its curvature at a first temperature with a snap action and re-inverts its curvature at a second temperature. A support is disposed in the housing opposite to the other side of the bimetal and has a preselected elasticity. A fixed contact member is disposed in the housing, and a movable contact member is held by a stationary member in the housing so as to be movable relative to the fixed contact member. A pressure strip is formed separately from or integrally with the movable contact member so as to project from and to be moved with it, the pressure strip having a distal end in contact with the support so that a force is applied to the bimetal at a predetermined pressure.

Abstract: A thermal motor protector includes a first support for supporting a thermally responsive element and a second support for supporting a fixed contact. The first and second supports are mounted on and insulated from a header plate. The thermally responsive element is secured to the first support through a fixing strip and has a central shallow dish-shaped portion and carries a movable contact at its distal end. A calibration mechanism includes a male screw, a hole formed in the first support and elastically slender clamping portions clamping the screw when it is screwed into the hole. The diameter of the hole is smaller than the outer diameter of the screw. The stiffness of the fixing strip is determined so that variations in the ratio of the current bypassed into the calibration mechanism to the current flowing through the fixing strip and thermally responsive element can be substantially ignored.

Abstract: An acceleration responsive switch, for operating an air bag system installed in an automobile, includes a cylindrical receptacle for containing an electrically conductive liquid such as mercury and an inert gas, a metallic lid having an open end and hermetically secured to the open end of the receptacle, and a pair of electrodes having one ends extended into the receptacle through the open end of the lid, respectively such that the one ends of the electrodes are brought into contact with the conductive liquid when a shock acting on the receptacle causes the conductive liquid to move within the receptacle.

Abstract: A thermally responsive switch includes an elliptic dome-shaped receptacle, a support conductively secured at one of two ends to an inner surface of one of two ends of the receptacle in the direction of its length, a bimetallic thermally responsive element secured at one end to the other end of the support with the other end opposite to an inner surface of the other end of the receptacle in the direction of its length with a predetermined space interposed therebetween, the thermally responsive element carrying a movable contact on the other end, and a metallic lid secured to the open end of the receptacle so as to hermetically close the open end of the receptacle. The lid has a through-hole through which a terminal pin is disposed with an electrically insulative material charged in the through-hole. Alternatively, two terminal pins may be disposed through two through-holes respectively.

Abstract: A thermally responsive switch used in enclosed motor-compressors includes a supporter formed of a single metallic plate and including a support arm cantilever mounting a thermally responsive bimetallic or trimetallic element carrying a movable contact at one end, first and second beams disposed in a relation that the support arm is interposed between these beams, and an operative temperature calibration strip integrally extended from the first beam. The calibration strip is slidably inserted between the support arm and the second beam into a wedge structure in the state that the calibration strip is bent at the root portion. Consequently, when the calibration strip is bent with the slidable movement, the support arm is bent so that the contact pressure between the contacts is set, an amount of bending deformation of the support arm corresponding to an amount of bending deformation of the calibration strip.

Abstract: This invention relates to a three-phase thermal protector having two pairs of fixed and movable contacts for opening and closing the neutral of wye-connected phase windings of a three-phase induction motor.

Abstract: A structure for mounting a motor protector substantially as a thermally responsive switch in an enclosed electric compressor including an electric motor and a compressing means provided in a closed housing. The structure includes a terminal support provided air-tightly through an upper wall of the compressor housing, a plurality of conductive pins for connecting an external power-supply circuit to the motor, the conductive pins projecting inside and outside the terminal support. One of the inner conductive pins is conductively connected to a terminal pin provided in the motor protector or to an equivalent thereof. Thus, the motor protector is disposed and held within the compressor housing so that heat is exchanged between the motor protector and a coolant gas. A motor winding is connected to the other terminals and the other conductive pins provided in the terminal support.

Abstract: A thermally responsive snap-acting switch consists of an elastic plate cantilever mounted at one end on a header, a thermally responsive element which includes a central dish-shaped portion for inducing snap action and one end of which is connected with the other end of the elastic plate in an opposed relation to the elastic plate, a support one end of which includes a portion receiving a connection between the elastic plate and the thermally responsive element so that it slides and is inclined on the receiving portion, and a projection which exerts a force on the dish-shaped portion of the thermally responsive element to calibrate the operative temperature of the thermally responsive element. The calibration is performed either by employing a screwed stud as the projection or by plastically deforming the receiving portion of the support.

Abstract: A thermally actuated switching device is disclosed that comprises a fixed contact placed on a proper member, a thermally actuated member such as a bimetallic member in the center of which is formed of a thin dish shape which contributes to a snap-action caused by heating of the bimetallic member, a bracket keeping the thermally actuated member in the concave-formed condition, a movable contact, which contacts on or removes from the fixed contact and is secured on the free end of the thermally actuated member, and a heat-resistant arc shield cantileverly held on the free end of the thermally actuated member or on a proper supporting member against the movable contact mounted surface of the thermally actuated member, so that the arc shield protects the thermally actuated member from an arc being introduced to it and prevents the deviation of the operation temperature of the thermally actuated member at the open or close action.

Abstract: A thermally responsive switch device includes; a bimetallic plate enclosed within a metallic enclosure in a cantilever manner and having a central dish-shaped portion for snap movement. The bimetallic plate carries a movable contact at one free end to be in making contact relationship with a fixed contact which is placed into the enclosure. A calibrator projection is provided with the enclosure to engage with the dish-shaped portion to exert point pressure between the contacts. A reinforcer extension is disposed in the enclosure and has one end secured to the inner side of the enclosure and its other end sandwiching the dish-shaped portion in cooperation with the projection so as to prevent the cantilever support end of the plate from being deformed irrespective of often repeated snap actions of the plate in response to the ambient temperature or the like.

Abstract: A snap action type thermally responsive switch comprising a fixed contact secured to a stationary frame, a rectangular thermally responsive plate having a central dish-shaped portion and being secured at one lengthwise end to the stationary frame and carrying a movable contact, the plate being determined at the ratio of length to width to be more than two, a calibrator screw projecting toward the convex side of the dish-shaped portion to depress thereagainst at the normal temperature, the calibrator means being positioned to contact the dish-shaped portion within the region ranging from the central point to a point away from the central point that is equal to one-third of the width of the plate in the direction toward the secured end thereof.

Abstract: A seismosensitive device comprises a hermetically sealed enclosure having a recess at the bottom, a first annular surface provided around the recess and having a radial gradient substantially of horizontal level and a second annular surface provided around the first annular surface and progressively diverging from the lower to upper portions with a slope having a gradient greater than that of the first annular surface. A switch assembly comprising a drop of mercury placed at the recess, an electrode bar provided with the enclosure, a needle contact secured to the electrode bar to have its lower end immersed into the drop is provided. When the mercury drop moves along the gradient surfaces significantly smoothly to separate from the needle contact upon tremor of the earth, the switch will open.

Abstract: In a hermetic type thermally responsive switch comprising a fixed contact support having a fixed contact at its end and cantilever disposed in a hermetically sealed vessel, a elongated support supporting a thermally responsive disk which has a movable contact and cantilever disposed in said vessel through a connecting means; said fixed contact support comprises laminated metallic sheets each having different elastic modulus, while a spacer means is interposed in electrically, thermally insulated relationship between said elongated support and said connecting means so as to calibrate the snap temperature of said disk.

Abstract: A thermally responsive switch comprises a housing enclosing a contact arm bearing a fixed contact and a thermally responsive snap-acting element designed to move and return with snap action depending upon the degree of switch self-generated heat or the ambient temperature. One end of the snap-acting element carries a movable contact and its other end is the supporting portion connected to a metallically elastic member mounted in the housing. To a stationary member integrated with the housing, an end support element and a central support element are respectively mounted. The end support element engages the supporting portion of the snap-acting element against the elastically urging force of the elastic member to push in one direction, while the central support element engages a middle portion of the snap-acting element to push in the opposite direction.

Abstract: In a seat belt retractor having a reel to which a belt is anchored at one end and which is spring biased pawl is pivotally mounted on a retractor frame for movement into and out of engagement with a pair of ratchet-toothed flanges provided on the reel. Disposed coaxially with the reel are a cam wheel rotatable simultaneously therewith and an inertia wheel rotatable through a predetermined angle relative to the cam wheel. These wheels have on and along their peripheries protuberances which are disposed at a predetermined pitch. During rotation of the reel in a direction of belt extension at relatively low acceleration, the inertia wheel is rotated in synchronism with the cam wheel via a spring. This spring yields, upon a high acceleration being imparted to the reel in the direction of belt extension, to permit the inertia wheel to lag behind the cam wheel by the predetermined angle.

Abstract: A seat belt retractor incorporates a fail-safe locking mechanism that is actuated by vehicle acceleration to lock a retractor drum against rotation in the belt unwinding direction. A pair of locking wheels are arranged coaxially with the drum for simultaneous rotation therewith, and a detent movable into and out of engagement with both locking wheels is biased, by biasing means such as a spring, into engagement therewith. Normally, the detent is restrained from engagement with the locking wheels against the force of the biasing means by an actuator associated with an inertial element constituting a part of acceleration sensing means. Upon displacement of the inertial element from its normal position of rest, the actuator permits the detent to move into engagement with the locking wheels by the force of the biasing means.