Raychem Limited

Other

Metcal, Inc.

Andrew Tomlinson

Mark S Thompson

Philip S Carter, Jr

John P Ekstrand

James M Taylor

Edward S Sherman

Michael Hodges

Michael Styrna

The invention is a circuit protection device comprising a first and a second female terminal. The device further comprises a first fuse clip in electrical contact with the first fuse terminal and a second fuse clip in electrical contact with the second fuse terminal. A positive temperature coefficient element, preferably planar, is positioned between and makes electrical contact with both the first fuse clip and the second fuse clip. In a first embodiment, at least one of the first and second fuse clips is spring-loaded, i.e., has an inherent resiliency. In this same embodiment, portions of the first and second fuse clips overlap, and the positive temperature coefficient element is secured between the overlapping portions of the first and second fuse clips. In the second of the two preferred embodiments, the first fuse clip, the second fuse clip, and the positive temperature coefficient element are generally coplanar.

Circuit protection device with female terminals and PTC element

A heater employs a ferromagnetic or like material heated by a varying magnetic field to heat the ferromagnetic material wherein the ferromagnetic material has a large cross-section comprised of many members of small cross-section insulated from one another and wherein for medical applications each member may be surrounded by a heat conductive electrically conductive coating.

Thermal induction heater

A conductive polymer composition which exhibits PTC behavior comprises a crystalline organic polymer, carbon black, and a high resistivity particulate filler. The high resistivity filler is semiconductive and has a resistivity at least 100 times that of the carbon black. Compositions of the invention exhibit good resistance stability when exposed to thermal cycling. They are useful in electrical devices requiring compositions with high resistivity.

Conductive polymer compositions

An electrical system which comprises (1) a temperature-sensitive device comprising a PTC or NTC element, (2) a load in series with the temperature-sensitive device and (3) a control device in parallel with the load and the temperature-sensitive device. The control device is a device whose resistance can be changed from a high value (which may be infinite) to a low value or vice versa, by a change in the electrical or physical environment thereof, e.g. a diode, triac, thyristor, PTC device or NTC device. The system is connected to a power supply so that, under normal conditions of operation, either (a) the temperature-sensitive device has a low resistance and the control device has a high resistance, whereby the load is activated, or (b) the temperature-sensitive device has a high resistance and the control device has a low resistance, whereby the load is isolated. By an appropriate change in the power source, e.g. its size or direction, or in the physical environment of the control device, e.g. its temperature, the relative resistances of the temperature-sensitive device and the control device can be reversed, thereby isolating or activating the load. The system is particularly useful for isolating a remote load, e.g. a telephone, while retaining a continuous circuit e.g. through the legs of a telephone circuit, for example for test purposes.

Growing community of inventors

Palo Alto, CA, United States of America

Andrew Tomlinson