Tyco Electronics Corporation

Other

Raychem Limited

William C Beadling

James J Toth

Justin N Chiang

Shou-Mean Fang

Michael T Zhang

Mark S Thompson

Martin G Pineda

Deepak Nayar

Thanh U Chung

A composite circuit protection device includes a laminar insulating member and first and second laminar circuit protection devices. Each of the first and second laminar circuit protection devices includes (1) a first laminar electrode, (2) a second laminar electrode, (3) a laminar PTC resistive element which (i) exhibits PTC behavior, (ii) has a first face to which the first electrode is secured and an opposite second face to which the second electrode is secured, and (iii) defines first and second apertures which run between the first and second faces, (4) a third laminar conductive member which (i) is secured to the second face of the PTC resistive element in the area of the first aperture, and (ii) is spaced apart from the second electrode, (5) a fourth laminar conductive member which (i) is secured to the first face of the PTC resistive element in the area of the second aperture, and (ii) is spaced apart from the first electrode, (6) a first transverse conductive member which lies within the first aperture defined by the PTC resistive element, runs between the first and second faces of the PTC element, is secured to the PTC element, and is physically and electrically connected to the first laminar electrode and to the third laminar conductive member, but is not connected to the second laminar electrode, and (7) a second transverse conductive member which lies within the second aperture defined by the PTC resistive element, runs between the first and second faces of the PTC element, is secured to the PTC element, and is physically and electrically connected to the second laminar electrode and to the fourth laminar conductive member, but is not connected to the first laminar electrode. The first and second laminar devices are physically secured together in a stacked configuration, with the laminar insulating member between them; and the devices are connected together electrically by interfacial electrical connections between adjacent electrodes and laminar conductive members so that when an electrical power supply is connected to (i) one of the electrodes and (ii) the third or fourth laminar member on the same face of the PTC resistive element as the electrode (i), the first and second laminar circuit protection devices are connected electrically in parallel.

Electrical devices

A laminar sensor ( ) for detecting changes on a laminar substrate ( ). The sensor includes a laminar sheet ( ) which has a first surface ( ) and a second opposite surface ( ), and is made from a conductive polymer composition which exhibits temperature dependent resistance behavior, preferably PTC behavior. A plurality of sensing elements ( ) are electrically connected, preferably in series, on the sensor. Each sensing element is formed as an electrode pair containing a first electrode and a second electrode. The first and second electrodes ( ) may be on the same surface of the laminar sheet or on opposite surfaces of the sheet. Two electrical leads ( ) are present for connecting the sensing elements into a circuit, which may be used to detect changes in resistance which occur when a sensing element is exposed to an elevated temperature, a change in pressure, or a solvent.

Distributed sensor

Electrical devices, particularly circuit protection devices, contain conductive polymer elements whose edges are formed by breaking the conductive polymer element, along a desired path, without the introduction of any solid body into the element. The resulting cohesive failure of the conductive polymer produces a distinctive fractured surface. One method of preparing such devices involves etching fracture channels in the electrodes of a plaque containing a PTC conductive polymer element sandwiched between metal foil electrodes, and then snapping the plaque along the fracture channels to form individual devices.

Electrical device

A laminar sensor for detecting changes on a laminar substrate. The sensor includes a laminar sheet which has a first surface and a second opposite surface, and is made from a conductive polymer composition which exhibits PTC behavior. A plurality of sensing elements are electrically connected in series on the sensor. Each sensing element is formed as an electrode pair containing a first electrode and a second electrode. The first and second electrodes may be on the same surface of the laminar sheet or on opposite surfaces of the sheet. Two electrical leads are present for connecting the sensing elements into a circuit, which may be used to detect changes in resistance which occur when a sensing element is exposed to an elevated temperature, a change in pressure, or a solvent.

Sensor

Electrical devices containing a conductive polymer element having a

A circuit protection device in which a PTC element made from a PTC composition includes or has at a boundary thereof a mechanical stress riser. The device will be tripped by, and provide reversible protection against, a first set of fault conditions, and will also provide protection at least one time against a second, more severe, set of fault conditions which cause physical disruption of the device and which cause the device to have a substantially infinite resistance. Devices of the invention are useful in protecting against relatively high voltages.

Growing community of inventors

San Jose, CA, United States of America

William C Beadling