High pressure sensor apparatus with low cost compact packaging system

• US 5,827,972 A
• Filed: 11/02/1993
• Issued: 10/27/1998
• Est. Priority Date: 11/02/1993
• Status: Expired due to Term

• Current Assignee: Sensata Technologies Incorporated (Sensata Technologies Holding Plc)
• Original Assignee: Texas Instruments, Inc.
• Inventors: Armacost, John M., Bishop, Robert P., Dague, Bryan J., Bartosh, Robert L., Balcarek, Richard J., Beringhause, Steven, Strott, Douglas B.
• Primary Examiner(s): FELBER, JOSEPH LEON
• Application Number:
  US08/146,868
• Time in Patent Office: 1,820 Days
• Field of Search: 73/756, 73/724, 73/726, 73/727, 29/621.1, 29/25.41, 338/4, 338/42, 361/283.1, 361/283.2, 361/283.3, 361/283.4
• US Class Current: 73/756
• CPC Class Codes: G01L 19/14 Housings G01L19/0007, G01L19/0084, G01L19/0092, G01L19/04, G01L19/06 take precedence
• CPC Class Codes: G01L 19/143 Two part housings
• CPC Class Codes: G01L 19/147 Details about the mounting of the sensor to support or covering means
• CPC Class Codes: G01L 9/0072 using variations in capacitance
• CPC Class Codes: G01L 9/0075 using a ceramic diaphragm, e.g. alumina, fused quartz, glass

Abstract

A fluid pressure sensor particularly useful for measuring pressure up to approximately 2000 psi has a hexport (12, 112, 212, 312) formed with a stop surface (26, 326) in a bottom wall (18) circumscribing a fluid pressure inlet (16). A pressure sensing module (22) is received on the stop surface and a distal end (40) of a wall (20, 120, 320) of the hexport is crimped to lock the pressure sensing module onto the stop surface with the stop surface limiting the amount of compression of an O-ring (30) disposed contiguous to and inboard of the stop surface. In one embodiment the crimp is placed directly on a metal ring (38) attached to a plastic connector (32) which in turn transfers the crimping force to the pressure sensing module. In other embodiments (FIGS. 2, 3) the crimp is placed directly in the pressure sensing module to form a subassembly. In one embodiment, a separate sleeve (142) member connects the subassembly to the plastic connector while in another embodiment the connector is provided with an extended skirt which snaps over the hexport to connect the connector to the subassembly. In yet another embodiment, the plastic connector (332) is formed with a strengthening flange (334) received around the pressure sensing module and the crimp is formed directly on the plastic connectors to reduce contact stresses in the crimp and compensate for crimp wall springback.

Claims

1. A pressure sensor comprising:

a metallic housing having a bottom wall formed with a fluid pressure inlet in the bottom wall and having a sidewall extending upwardly from the bottom wall to a distal end,

a pressure sensing module having a pressure responsive surface communicating with the fluid pressure inlet and disposed within the housing closely adjacent the upwardly extending sidewall, the upwardly extending sidewall circumscribing the pressure sensing module,

an annular stop surface integrally formed as part of the bottom wall, the stop surface disposed a selected first distance above the remainder of the bottom wall, the pressure sensing module received on the stop surface,

a seal formed of resilient material received on the bottom wall contiguous to and inboard of the stop surface, the seal formed of resilient material having a height of a second distance greater than the first distance whereby compression of the seal by the pressure sensing module is limited by the stop surface,

the distal end of the upwardly extending sidewall being crimped inwardly to place a force on the pressure sensing module biasing the module against the stop surface, and

a connector attached to the housing to provide electrical connection to the pressure sensing module.

2. A pressure sensor according to claim 1 in which the connector comprises an electrically insulative member mounting electrical leads through a bottom wall of the member, the member having an annular flange, a metallic annular element having a top surface and an inner surface, the inner surface being attached to the annular flange and the top surface being engaged by the crimped distal end of the sidewall of said metallic housing.

3. A pressure sensor according to claim 1 in which the crimped distal end of the sidewall of said metallic housing engages the pressure sensing module, the connector comprising an electrically insulative member mounting electrical leads through a bottom wall of the member, the member having an annular flange and further comprising a metallic sleeve having first and second ends, the sensor received within the sleeve with the first end of the sleeve crimped over the annular flange of the member and the second end of the sleeve crimped onto the metal housing to interconnect the connector and the housing.

4. A pressure sensor according to claim 3 further including a resilient seal disposed between the annular flange of the member and the crimped distal end of the upstanding sidewall.

5. A pressure sensor according to claim 1 in which the crimped distal end of the sidewall of said metallic housing engages the pressure sensing module, the connector comprising an electrically insulative member mounting electrical leads through a bottom wall of the member, the member having an annular flange with a skirt depending downwardly therefrom to a free distal end, an inwardly extending lip formed at the free distal end of the skirt, the lip being adapted to snap over a portion of the metal housing to interconnect the connector and housing.

6. A pressure sensor according to claim 5 further including a resilient seal disposed between the skirt and the metal housing.

7. A pressure sensor according to claim 1 in which the connector comprises an electrically insulative member mounting electrical leads through a bottom wall of the member, an annular shoulder integrally attached to the bottom wall of the member, the shoulder having a top surface and a bottom surface, the bottom surface engaging the pressure sensing module and the crimped distal end of the upwardly extending sidewall of the housing engaging the top surface of the shoulder.

8. A pressure sensor according to claim 7 in which the connector is composed of a reinforced resin.

9. A pressure sensor according to claim 7 in which the connector is composed of one of polyphenylene oxide/nylon and polyetherimide.

10. A pressure sensor according to claim 1 in which the pressure sensing module has a side wall extending between top and bottom surfaces, and in which the connector comprises an electrically insulative member mounting electrical leads through a bottom wall of the member, an annular shoulder integrally attached to the bottom wall of the member, the shoulder having a bottom surface engaging the pressure sensing module and an annular wall portion extending downwardly from the bottom surface over at least a portion of the side wall of the pressure sensing module.

11. A pressure sensor according to claim 1 in which the pressure sensing module is generally cylindrical having a bottom surface with a circular outer peripheral surface portion and the annular stop surface is aligned and engaged with the outer peripheral surface portion.

12. A pressure sensor according to claim 1 in which the pressure sensing module is generally cylindrical having a bottom surface with a circular outer peripheral surface portion and the annular stop surface is aligned and engaged with the bottom surface inboard of the outer peripheral surface portion.