Cylinder pressure sensor for an internal combustion engine
First Claim
1. A pressure responsive device for providing an electrical signal comprising a body of ceramic piezoelectric material having a first surface and an opposite surface, and a mounting arrangement for the body permitting the piezoelectric material between those surfaces to be compressed in response to an applied pressure to provide an electrical signal more precisely corresponding to the pressure, the mounting arrangement including a rigid load-spreading means having one end which is juxtaposed to a predetermined major portion of the first body surface and having rigid securing means which extend over all of said major first body surface portion precisely conformed to and rigidly secured to each and every part of that major first body surface portion to be in substantially uniform load-transferring relation to each and every part of that major first body surface portion, a rigid support means having one end which is juxtaposed to a predetermined major portion of the opposite body surface and having rigid securing means which extends over all of said major opposite body surface portion precisely conformed to and rigidly secured to each and every part of that major opposite body surface portion to be in substantially uniform load-transferring relation to each and every part of that major opposite body surface portion to form a combination piezoelectric unit, and the support means of the combination unit is fixedly attached to a rigid mounting body at a selected location so that the remainder of the combination unit including the body of piezoelectric material and the load-spreading means extend therefrom in cantilever relation to receive an applied pressure on the load-spreading means to compress the piezoelectric body material disposed between said major surface portions of the body of piezoelectric material to a substantially uniform extent to provide an electrical signal precisely corresponding to the applied pressure, said rigid securing means comprising the product resulting from forming said securing means in situ against said major body surface portions to be precisely conformed to each and every part of said major body surface portions.
2 Assignments
0 Petitions
Accused Products
Abstract
A presure sensor for providing an electrical signal corresponding to pressure in a cylinder of an automotive engine has a rigid load-spreading element rigidly secured to a first surface of a ceramic piezoelectric body by a rigid bonding material precisely conformed to the first surface to be in substantially uniform load-transferring relation to all parts of the first body surface, has a rigid support member rigidly secured to a parallel, opposite surface of the ceramic piezoelectric body by a rigid bonding material precisely conformed to the opposite surface to be in substantially uniform load-transferring relation to all parts of the opposite body surface to form a piezoelectric unit and has a peripheral part of the rigid support member precisely mounted with an interference fit in a bore in a metal component of a mounting structure so that the body of a piezoelectric material and the load-spreading element extend in a cantilever relation at a precisely determined location to be engaged by force applied through a diaphragm in response to an applied pressure to provide an electrical signal precisely corresponding to the pressure.
54 Citations
22 Claims
- 1. A pressure responsive device for providing an electrical signal comprising a body of ceramic piezoelectric material having a first surface and an opposite surface, and a mounting arrangement for the body permitting the piezoelectric material between those surfaces to be compressed in response to an applied pressure to provide an electrical signal more precisely corresponding to the pressure, the mounting arrangement including a rigid load-spreading means having one end which is juxtaposed to a predetermined major portion of the first body surface and having rigid securing means which extend over all of said major first body surface portion precisely conformed to and rigidly secured to each and every part of that major first body surface portion to be in substantially uniform load-transferring relation to each and every part of that major first body surface portion, a rigid support means having one end which is juxtaposed to a predetermined major portion of the opposite body surface and having rigid securing means which extends over all of said major opposite body surface portion precisely conformed to and rigidly secured to each and every part of that major opposite body surface portion to be in substantially uniform load-transferring relation to each and every part of that major opposite body surface portion to form a combination piezoelectric unit, and the support means of the combination unit is fixedly attached to a rigid mounting body at a selected location so that the remainder of the combination unit including the body of piezoelectric material and the load-spreading means extend therefrom in cantilever relation to receive an applied pressure on the load-spreading means to compress the piezoelectric body material disposed between said major surface portions of the body of piezoelectric material to a substantially uniform extent to provide an electrical signal precisely corresponding to the applied pressure, said rigid securing means comprising the product resulting from forming said securing means in situ against said major body surface portions to be precisely conformed to each and every part of said major body surface portions.
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13. A piezoelectric unit for use in a pressure responsive device to provide an electrical signal in response to an applied pressure comprising a body of ceramic piezoelectric material having a first surface and an opposite surface to be compressed between the surfaces in response to an applied pressure to provide an electrical signal corresponding to the pressure, a rigid load-spreading element having one end juxtaposed to a predetermined major portion of the first body surface and an opposite body end for receiving an applied pressure thereon, a rigid organic-based layer of bonding material which extends over all of said first major body surface portion precisely conformed to said one end of the rigid load-spreading element and to each and every part of said first major body surface portion for rigidly securing the element in substantially uniform load-transferring relation with each and every part of the first major body surface portion, a rigid support member having sufficient thickness to be substantially rigid having one end juxtaposed to a predetermined major portion of the opposite body surface for mounting the unit, and a rigid organic-based layer of bonding material which extends over all of said opposite major body surface portion precisely conformed to said one end of the rigid support member and to each and every part of said opposite major body surface portion for rigidly securing the support in substantially uniform load-transferring relation with each and every part of the opposite major body surface portion, said bonding material comprising the product resulting from forming said bonding material in situ against said major body surface portions to be precisely conformed to each and every part of said major body surface potions.
- 15. A pressure responsive device for providing an electrical signal comprising a body of ceramic piezoelectric material having a first surface and an opposite surface having relatively thin electrical contacts thereon, and a mounting arrangement for the body to permit the piezoelectric material between those surfaces to be compressed in response to an applied pressure to provide an electrical signal corresponding to the pressure, the mounting arrangement including a rigid load-spreading element having one end juxtaposed to the electrical contact on a predetermined major portion of the first body surface, a rigid organic-based layer of electrically-conductive bonding material which extends over all of said first major body surface portion precisely conformed to said one end of the load-spreading element and to each and every part of said one electrical contact on said first major body surface potion in electrical engagement with said contact for rigidly securing the element in substantially uniform load-transferring relation to each and every part of said first body major body surface portion, a rigid support member having sufficient thickness to be substantially rigid having one end surface juxtaposed to the other electrical contact on a predetermined major portion of the opposite body surface, a rigid organic-based layer of electrically conductive bonding material which extends over all of said opposite major body surface portion precisely conformed to said one end surface of the rigid support member and in electrical engagement with said other electrical contact for rigidly securing the support member in substantially uniform load-transferring relation to each and ever part of said opposite major body surface portion to form a combination piezoelectric unit, a rigid metal component having a through bore therein, and diaphragm means secured to the metal component in sealing relation to one end of the bore to apply force to the load-spreading element in response to an applied pressure, a peripheral portion of the rigid support member in the combination piezoelectric unit being disposed with an interference fit in the bore so that the body of piezoelectric material and the load-spreading element extend therefrom in cantilever relation to dispose an opposite end of the load-spreading element to be engaged by the diaphragm means in response to applied pressure to provide an electrical signal precisely corresponding to the applied pressure, said bonding material comprising the product resulting from forming said bonding material situ against said major body surface portions to be precisely conformed to each and every part of said major body surface portions.
Specification