Abstract: A telephone line overcurrent protector adapted to be mounted on a circuit board is shown having a cup shaped housing in which a PTC element is placed with leads extending out of the housing through apertures in a bottom cover. The bottom cover is formed in one embodiment with a frangible diaphragm to provide guided pressure release upon catastrophic failure of the PTC element, in another embodiment with open apertures in the bottom cover and in yet another embodiment with means to mount a snap out member closing an aperture in the bottom cover, both for the same purpose of providing guided pressure release.

Abstract: A split phase electric motor starter and protector are shown having a housing which receives a PTC starter switch and a motor protector and provides various wiring options for connecting the PTC switch and, if desired, a capacitor to a motor depending upon the particular requirements of an application. The housing optionally accommodates a capacitor support bracket.

Abstract: A motor winding system having a main winding and a start winding circuit with a start winding and a PTC resistor in series therewith wherein the resistor is electrically removed from the circuit at a predetermined time after motor starting and remains in this state until motor shut off. The start winding circuit also includes a bimetallic switch in series with the resistor and a series circuit of a capacitor and an electromagnet in parallel with the resistor and switch. At motor start up, current from the main power source is applied across the main winding and the start winding circuit heats up the resistor and causes an increase in the resistance thereof. Also, current through the switch and PTC heat causes the bimetallic element to snap or move when it has reached a predetermined temperature to open the start winding circuit.

Abstract: A circuit breaker has two thin flat terminals embedded in an electrically insulating housing exposing respective broad flat sides of the terminals in spaced side-by-side relation to each other in a housing chamber. The circuit breaker has a thermostat metal member secured at one end to one exposed side of one terminal to mount the member extending along a chamber wall and has a contact at its opposite end to engage and disengage the other terminal to close and open a circuit in response to a selected current in the circuit. The contact comprises a material which erodes during repeated cycling of the circuit breaker. The thermostat metal member has a portion of reduced cross-sectional area adapted to burn out and separate the member into two sections to open the circuit if the contact welds or sticks to the other terminal. A stop on the housing intercepts movement of one of the member sections after burn out to avoid shorting of the circuit.

Abstract: A circuit breaker device has a chamber in which is disposed a single break contact system using low contact resistance material mounted on movable and stationary supports arranged in a loop configuration in order to direct arcs between the contacts through an arc chute into a remote portion of the chamber. A push-button is connected through a kinematic linkage which transfers motion using minimal frictional engagement to a movable contact to bring the movable contact into and out of engagement with a stationary contact and to latch the contacts in engagement during normal operation. A cantilevered current carrying bimetal transfers motion caused by I R heating of the bimetal to an ambient compensating bimetal connected to the latch mechanism. The kinematic linkage includes a latch surface which engages a rollable cylindrical reaction surface of the latch mechanism to cause the movable contact to come into engagement with the stationary contact upon depression of the push-button.

Abstract: A circuit breaker device has a chamber in which is disposed a single break contact system using low contact resistance material mounted on movable and stationary supports arranged in a loop configuration in order to direct arcs between the contacts through an arc chute into a remote portion of the chamber. A push-button is connected through a kinematic linkage which transfers motion using minimal frictional engagement to a movable contact to bring the movable contact into and out of engagement with a stationary contact and to latch the contacts in engagement during normal operation. A cantilevered current carrying bimetal transfers motion caused by I2R heating of the bimetal to an ambient compensating bimetal connected to the latch mechanism. The kinematic linkage includes a latch surface which engages a rollable cylindrical reaction surface of the latch mechanism to cause the movable contact to come into engagement with the stationary contact upon depression of the push-button.

Abstract: A circuit breaker device has a chamber in which is disposed a single break contact system using low contact resistance material mounted on movable and stationary supports arranged in a loop configuration in order to direct arcs between the contacts through an arc chute into a remote portion of the chamber. A push-button is connected through a kinematic linkage which transfers motion using minimal frictional engagement to a movable contact to bring the movable contact into and out of engagement with a stationary contact and to latch the contacts in engagement during normal operation. A cantilevered current carrying bimetal transfers motion caused by I.sup.2 R heating of the bimetal to an ambient compensating bimetal connected to the latch mechanism. The kinematic linkage includes a latch surface which engages a rollable cylindrical reaction surface of the latch mechanism to cause the movable contact to come into engagement with the stationary contact upon depression of the push-button.

Abstract: A compact, low cost, snap-acting thermostatic switch which can be automatically assembled comprising a single member housing, an unrestrained snap-acting disc, a stationary contact means and a movable contact means with a transfer means attached thereto in which calibration in assembled form can be performed as a single final operation.

Abstract: A system for monitoring usage of seat belt means in a motor vehicle includes electrically operable visual signaling means and electrically operable audible signaling means. A first switch is operable in response to initiation of motor vehicle operation for connecting the signaling means to an electrical power supply in the vehicle. An additional switch is operable in response to fastening of the vehicle seat belt means for preventing operation of the audible signaling means. An electrical resistor of positive temperature coefficient of resistivity is arranged to be heated to a selected temperature with a selected time delay after initiation of motor vehicle operation for preferably terminating operation of both signaling means after such time delay even if the vehicle seat belt means are not fastened.

Abstract: A system for monitoring usage of seat belt means in a motor vehicle includes electrically operable visual signaling means and electrically operable audible signaling means. A first switch is operable in response to initiation of motor vehicle operation for connecting the signaling means to an electrical power supply in the vehicle. An additional switch is operable in response to fastening of the vehicle seat belt means for preventing operation of the audible signaling means when the seat belt means are properly fastened. A pair of first electrical resistors of positive temperature coefficient of resistivity which are adapted to display a sharp increase in resistivity when heated to predetermined operating temperatures are arranged in series between the vehicle power supply and the visual and audible signaling means respectively for terminating operation of said signaling means individually when said first resistors are heated to said operating temperatures.