Hermetic mounting system for a pressure transducer
First Claim
1. A transducer for measuring a pressure comprising:
- a diaphragm having a relatively thin center section, said diaphragm being fixed in response to variations of a pressure to be measured, having disposed on one side of said center section a strain sensitive element;
a main support member for said diaphragm having a first and second end and a passageway extending therethrough, said diaphragm bonded to said first end of said main support member so that said center section is in substantial alignment with said passageway of said main support member;
support collar means surrounding a section of said main support member having a space between said main support member and said support collar means, and said support collar means extending to form a housing having walls and a base adapted to be connected to said pressure, said walls and said base enclosing said diaphragm and said main support; and
a sealing glass which occupies said space between said support collar means and said main support member providing a hermetic seal therebetween.
1 Assignment
0 Petitions
Accused Products
Abstract
A pressure transducer (50) of the type utilizing a diaphragm (8) with strain sensitive elements (14) formed in the diaphragm surface where the strain sensitive elements (14) are connected to an electronics assembly (4) to produce an electrical output in response to deflection of the diaphragm (8). A diaphragm assembly (26) is bonded to an intermediate support member (28) which is in turn bonded to a main support member (32) which is joined to a support collar (42) and hermetically sealed thereto with a sealing glass (40) where each element (2, 28, 32, 42) has a substantially matched coefficient of thermal expansion so as to reduce any induced thermal stresses and resultant measurement errors where the sealing glass (40) and the support collar (42) have a greater coefficient to produce a compressive type seal at high temperature. A pressure fitting (58) is joined to the external fluid pressure to be measured where the fluid is conducted to the diaphragm (8) through a plurality of passageways (30, 34, 56) in the support elements (28, 32, 44). A main housing (48) encloses the pressure sensing assembly (2) and support members (28, 32, 42) thereby providing protection from the environment.
94 Citations
32 Claims
-
1. A transducer for measuring a pressure comprising:
-
a diaphragm having a relatively thin center section, said diaphragm being fixed in response to variations of a pressure to be measured, having disposed on one side of said center section a strain sensitive element; a main support member for said diaphragm having a first and second end and a passageway extending therethrough, said diaphragm bonded to said first end of said main support member so that said center section is in substantial alignment with said passageway of said main support member; support collar means surrounding a section of said main support member having a space between said main support member and said support collar means, and said support collar means extending to form a housing having walls and a base adapted to be connected to said pressure, said walls and said base enclosing said diaphragm and said main support; and a sealing glass which occupies said space between said support collar means and said main support member providing a hermetic seal therebetween. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
-
-
13. A transducer for measuring a pressure comprising:
-
a lower transducer member adapted to be connected to a source of pressure to be measured, said lower transducer member having a passageway; a housing having walls and joined to said lower transducer member forming a cavity; a diaphragm having a relatively thin center section, said diaphragm being flexed in response to variations of a pressure to be measured, having disposed on one side of said center section a strain sensitive element; an intermediate support member for said diaphragm formed of an electrically insulating glass, said intermediate support member having a first end and a second end with a passageway extending therethrough, said diaphragm bonded to the first end of said intermediate support member so that said active area is in substantial alignment with said passageway; a main support member for said intermediate support member having a first and a second end with a passageway extending therethrough, said second end of said intermediate support member bonded to said first end of said main support member so that said passageway of said main support member is in substantial alignment with said passageway of said intermediate support member; a support collar surrounding said main support member and attached to said lower transducer member inside said cavity and having a void between said support collar and said main support member; and a sealing glass which occupies said void between said support collar and said main support providing a hermetic seal therebetween. - View Dependent Claims (14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25)
-
-
26. A transducer for measuring a pressure comprising:
-
a lower transducer member adapted to be connected to a source of pressure to be measured, said base having a passageway; a main housing having walls and attached to said lower transducer member forming a cavity; a crystalline diaphragm having a relatively thin center section, said diaphragm being flexed in response to variations of said pressure, having disposed on one side of an active area thereof at least one strain sensitive element with a thicker support portion at the periphery of said diaphragm; an intermediate support member for said diaphragm formed of a borosilicate glass, said intermediate support member having a first end and a second end with a passageway extending therethrough, said diaphragm thicker support portion anodically bonded to the first end of said intermediate support member so that said active area is in substantial alignment with said passageway said intermediate support member having a coefficient of thermal expansion substantially equal to said diaphragm; a main support member for said intermediate support member formed of a crystalline silicon having a first end and a second end and a passageway extending therethrough, said second end of said intermediate support member anodically bonded to said passageway of said main support member so that said passageway of said main support member so that said passageway of said main support member is in substantial alignment with said passageway of said intermediate support member said main support member having a coefficient of thermal expansion substantially equal to said intermediate support member; a support collar formed of a precipitation hardened steel surrounding a section of said main support member and attached to said lower transducer member and having a void between said support collar and said main support member said support collar having a coefficient of thermal expansion approximately four times as great as that of said main support member; a support washer having a passageway therethrough in substantial alignment with said passageway of said main support member located at said second end of said main support member, a peripheral edge of said support washer contacting said support collar; a sealing glass which occupies said void between said support collar and said main support member providing a hermetic seal therebetween said sealing glass having a coefficient of thermal expansion of 0% to 50% greater than that of said main support member; an electrical signal conditioning means mounted in said housing and electrically connected to said strain sensitive element; and an electrical connector mounted to said housing at an end opposite to said lower transducer member and electrically connected to said electrical signal conditioning means. - View Dependent Claims (27, 28, 29, 30, 31, 32)
-
Specification