Oil pressure transducer

• US 4,805,460 A
• Filed: 11/03/1987
• Issued: 02/21/1989
• Est. Priority Date: 11/03/1987
• Status: Expired due to Fees

• Current Assignee: Chrysler Motors Corp (Stellantis NV)
• Original Assignee: Chrysler Motors Corp (Stellantis NV)
• Inventors: Griffin, Ranald L., Kerstiens, Anthony J., Glover, Alfred H., Betterton, Joseph T.
• Primary Examiner(s): WOODIEL, DONALD
• Application Number:
  US07/116,438
• Time in Patent Office: 476 Days
• Field of Search: 73/725, 73/719, 73/746, 338/42, 338/39
• US Class Current: 73/725
• CPC Class Codes: H01H 3/0213 Combined operation of electric switch and variable impedance, e.g. resistor, capacitor H01H9/061 takes precedence
• CPC Class Codes: H01H 35/34 actuated by diaphragm

Abstract

A pressure transducer to measure and indicate fluid pressure levels including a housing in which a diaphragm and piston assembly is movable in response to pressure changes, the piston having a portion extending therefrom to engage a switch contact thereby disengaging the switch when the fluid pressure falls below a desired level.

Claims

1. An improved fluid pressure transducer, comprising:

generally hollow first and second housing members attached together in an end to end manner;

a diaphragm member with a peripheral edge and a flexible mid portion, the edge being attached between the housings and the mid portion having first and second surfaces whereby the first surface is exposed to pressurized fluid and the second surface is exposed to atmosphere thereby generating a net pressure force on the mid portion;

a piston member having an end portion operatively attached to the mid portion, an integral tubular portion of the piston extending within the second housing, whereby the piston is supported for axial reciprocation in the interior of the second housing corresponding to the movements of the mid portion;

the second housing having an outwardly extending end wall which defines an end recess;

a terminal support member insertably adjustable within the recess and having an elongated central portion which extends generally co-axially into the interior of the second housing;

an electrical circuit board attached to the terminal support member and extending in the axial direction with respect to the piston member and through the interior of the tubular piston, an electrical resistance grid on one exposed surface of the circuit board;

a contact support member attached to the piston for movements therewith and having a contact thereon adapted to slide along the elongated grid as the piston moves relative to the stationary circuit board;

the central portion of the terminal support member is separated into two spaced side edge portions to engage and support the board yet expose the surface of the board and the grid thereon to the contact portion of the assembly, whereby the resistance of a pressure indicating circuit including the contact and the circuit board varies in response to the relative movement therebetween and corresponding to the pressure of fluid adjacent to the diaphragm.

2. An improved fluid pressure transducer, comprising:

generally hollow first and second housing members attached together in an end to end manner;

a diaphragm member with a peripheral edge and a flexible mid portion, the edge being attached between the housings and mid portion having first and second surfaces whereby the first surface is exposed to pressurized fluid and the second surface is exposed to atmosphere thereby generating a net pressure force on the mid portion;

a piston member having an end portion operatively attached to the mid portion, an integral tubular portion of the piston extending within the second housing, whereby the piston is supported for axial reciprocation in the interior of the second housing corresponding to the movements of the mid portion;

the second housing having an outwardly extending end wall which defines an end recess;

a terminal support member insertably adjustable within the recess and having an elongated central portion which extends generally co-axially into the interior of the second housing;

an electrical circuit board attached to the terminal support member and extending in the axial direction with respect to the piston member and through the interior of the tubular piston, an electrical resistance grid on one exposed surface of the circuit board;

a contact support member attached to the piston for movements therewith and having a contact thereon adapted to slide along the elongated grid as the piston moves relative to the stationary circuit board;

the dimensions of the recess and the terminal support member are such relative to one another that the insertion of the support member in the recess is resisted by significant friction sufficient to maintain the support member in the recess despite normal attachment and detachment forces exerted thereon by an associated electrical connector, whereby the resistance of a pressure indicating circuit including the contact and the circuit board varies in response to the relative movement therebetween and corresponding to the pressure of fluid adjacent the diaphragm.