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US 5,212,466 AGranted
PTC thermistor and manufacturing method for the same
AssigneeFujikura Ltd.
InventorsMakoto Yamada, Setsuya Isshiki, Yukihiko Kurosawa, Masakazu Kuroda, Mori Hayashi
Life of this patent
Estimating the term…
Abstract
PTC (positive temperature coefficient) thermistors of a novel configuration and a method for their manufacture. The PTC thermistors have a PTC element sandwiched between two electrodes for which leads are formed as an extension of each of the two electrodes protruding beyond the edge of the PTC element. Several manufacturing methods avoid undue thermal and physical stress to the PTC composition while providing PTC thermistors having a variety of shapes and configurations.
Claims13
A PTC thermistor manufactured by a method including the steps of:
- (a) preparing a substantially flat plate shaped section of PTC composition demonstrating positive temperature coefficient behavior and having two contact surfaces;
- (b) preparing a pair of electrode plates each having a contact surface of which the surface area is greater than the corresponding contact surface of said section of PTC composition, said contact surface having a lead portion and a non-lead portion;
- and
- (c) sandwiching said section of PTC composition between said non-lead portions of said contact surfaces of said pair of electrode plates so that the non-lead portions of the contact surface of each of said pair of electrode plates comes to be bonded to a respective contact surface of said section of PTC composition and so that at least one lead portion of one contact surface of said electrode plates is caused to extend beyond said section of PTC composition and to provide an exposed planar conductive lead surface which extends beyond said section of PTC composition.
1 more element
A PTC thermistor manufactured by a method including the steps of:
- (a) preparing a substantially flat plate shaped sheet of PTC composition demonstrating a positive temperature coefficient behavior and having two contact surfaces;
- (b) preparing a pair of electrode plates each having a contact surface, each said contact surface having a plurality of lead portions and non-lead portions;
- (c) sandwiching said sheet of PTC composition between said contact surfaces of said pair of electrode plates so that at least a plurality of portions of each said contact surface of said sheet of PTC composition comes to be bonded to corresponding portions of said contact surfaces of said pair of electrode plates thereby forming a PCT thermistor plate;
- (d) cutting said PCT thermistor plate into a plurality of PCT thermistor chips, each of said PCT thermistor chips having non-lead sections which include a corresponding non-lead portion from each of said electrode plates and at least one lead section which includes a corresponding lead portion from at least one of said electrode plates;
- and
- (e) removing the PTC composition and the overlying portion of one of the plates from said at least one lead section, leaving the overlying portion of the other of the plates thereby forming an at least one electrical lead having an exposed conductive planar surface coplanar with the non-lead portion of said other of the plates.
3 more elements
A thermistor chip product made by the process of:
- (a) preparing a sheet of PTC composition demonstrating positive temperature coefficient behavior and having two contact surfaces;
- (b) preparing a pair of electrode plates each having a contact surface, each said contact surface having a plurality of lead portions and non-lead portions;
- (c) interposing a non-adhering agent in a plurality of locations between at least one contact surface of said sheet of PTC composition and at least one contact surface of at least one of said electrode plates;
- (d) sandwiching said sheet of PTC composition between said contact surfaces of said pair of electrode plates so that at least a plurality of portions of each said contact surface of said sheet of PTC composition comes to be bonded to corresponding portions of said contact surfaces of said pair of electrode plates thereby forming a PCT thermistor plate, and whereby said non-adhering agent is disposed between said at least one contact surface of said sheet of PTC composition and said at least one contact surface of said at least one electrode plate;
- (e) cutting said PTC thermistor plate into at least one PCT thermistor chip, said at least one PCT thermistor chip having non-lead sections which include a corresponding non-lead portion from each of said electrode plates and at least one lead section which includes a corresponding lead portion from at least one of said electrode plates and wherein said non-adhering agent is disposed between said at least one lead portion and the contact surface of the PTC composition adjacent it in said contact section.
2 more elements
A PTC thermistor comprising:
- (a) a section of PTC composition having a periphery and having positive temperature coefficient behavior;
- and
- (b) a pair of electrode plates disposed in contact with said PTC composition so that the section of PTC composition is sandwiched therebetween, at least one of said electrode plates having a lead portion integrally formed with a non-lead portion and said lead portion extending beyond the periphery of said section of PTC composition and providing an exposed planar conductive surface coplanar with the non-lead portion of the electrode plate thereby forming at least one electrical lead.
A PTC thermistor comprising:
- (a) a section of PTC composition having a periphery and having positive temperature coefficient behavior;
- and
- (b) a pair of rigid electrode plates disposed in contact with said PTC composition so that the section of PTC composition is sandwiched therebetween, each of said electrode plates having a lead portion integrally formed with a non-lead portion and said lead portion extending beyond the periphery of said section of PTC composition each lead portion thereby forming an electrical lead and each lead portion which extends beyond the periphery of the section of PTC composition being structurally self-supporting.
The PTC thermistor of claim 11, wherein said lead portion extending beyond the periphery of said section of PTC composition is self-supporting.
A PTC thermistor comprising:
- (a) a section of PTC composition having a periphery and having positive temperature coefficient behavior and being comprised substantially of an organic substance in which an electrical conductor is dispersed;
- and
- (b) a pair of electrode plates disposed in contact with said section of PTC composition so that said section is sandwiched therebetween, at least one of said electrode plates having a lead portion integrally formed with a non-lead portion and said lead portion extending beyond the periphery of said section of PTC composition, such that said lead portion provides an exposed planar conductive surface free from contact with said section of PTC composition, thereby forming at least one electrical lead;
- wherein each of said non-lead portions of said electrode plates and said PTC composition comprises a substantially curved peripheral edge,
- and wherein said at least one electrical lead extends from said substantially curved peripheral edge of at least one of said non-lead portions.
2 more elements
Dependencies are inferred from the claim text.