×

Pressure checked electrical pressure switch

  • US 4,752,658 A
  • Filed: 06/22/1987
  • Issued: 06/21/1988
  • Est. Priority Date: 06/22/1987
  • Status: Expired due to Fees
First Claim
Patent Images

1. An electrical pressure switch for detecting a minimum operating pressure of a hydraulic system, comprising:

  • piston means for moving between first and second preselected positions in response to detecting a preselected pressure;

    means for switching between first and second conductive states in response to movement of the piston means between the first and second preselected positions; and

    means for fluidicly isolating the piston means from the hydraulic system in response to movement of the piston means from the first to the second preselected positions;

    wherein the piston means includes a housing having first and second end portions, and a bore of a preselected diameter opening onto the first end portion, a piston having first and second end portions and being disposed within the housing bore adjacent the housing first end portion, the piston first end portion being in fluid communication with the hydraulic system, a plunger having first and second end portions and being disposed within the housing adjacent the housing second end portion, the plunger first end portion being in contacting relation with the piston second end portions;

    wherein the isolating means includes the piston first and second end portions having preselected diameters respectively greater than and less than the bore opening diameter, and the hosuing bore having seat disposed about the periphery of the bore at the first end portion of the housing, the seat receiving the first end portion of the piston in a fluid sealing relationship upon an overpessure condition.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×