Flush valve

Claim 2

In a valve of the class having a housing with an internal flow passage having an inlet and an outlet thereto with a primary seat therein, a piston carrying a primary seal to engage said primary seat, a cylinder in which said piston is reciprocable, and valve means controlling the venting of said cylinder to move the piston toward and away from the primary seal so as to close or to open the valve, respectively, the improvement comprising: a probe carried by said piston and extending through the primary seat into the flow passage and terminating upstream of the primary seat, there being a passage through the probe from the region of termination to the cylinder, an restrictor element slidably fitted to said probe upstream of said primary seal, and a spring biasing the restrictor element toward the upstream direction, the restrictor element comprising an annular body adapted to make a variable area orifice in said flow passage downstream from the free end of the probe.

Claim 3

Apparatus according to claim 1 in which fins are disposed on the probe to maintain it in alignment.

Claim 4

Apparatus according to claim 1 in which a counterbore is formed in the flow passage upstream from the primary seat with which the restrictor element cooperates to form said variable area orifice.

Claim 5

Apparatus according to claim 1 in which a deflector surface is formed adjacent to and surrounding said primary seal to direct fluid laterally from said primary seal.

Claim 6

Apparatus according to claim 4 in which a concave peripheral groove is formed in the outer wall of the piston, the deflector surface being upstream therefrom and of greater diameter.

Claim 7

A valve operable by differential fluid pressure, comprising: a housing with an internal flow passage having an inlet and an outlet; a primary seat in said flow passage; a cylinder having a central axis; a piston making a sliding, fluid sealed fit in said cylinder, and axially shiftable therein; a primary seal carried by said piston adapted to engage the primary seat and close the flow passage in one axial position of the piston, and to leave it open in another axial position thereof; a probe mounted to said piston and passing through the primary seat, and having a bore extending from the downstream end of the piston to a portion of the probe upstream from the primary seat in all axial positions of the piston; a vent passage extending from the cylinder on the downstream side of the piston to a region of lesser pressure than the pressure supplied to the valve; a poppet valve adapted to open or to close said vent passage, whereby to connect said cylinder to said lesser pressure, or to leave it closed so that the bore conducts supply pressure to said cylinder, thereby shifting said piston to open and to close the flow passage at the primary seat, respectively; a position lock to restrain the poppet valve in its open position until contacted by the piston; a restrictor element slidably fitted to said probe upstream of said primary seal; a spring biasing the restrictor element toward the upstream direction, the restrictor element comprising an annular body adapted to make a variable area orifice in said flow passage downstream from the free end of the probe; an annular deflector surface on said piston surrounding and adjacent to said primary seal to direct fluid laterally from said primary seal; and a concave peripheral groove in the outer wall of the piston of lesser lateral extent than the deflector surface.

Claim 8

A valve operable by differential fluid pressure, comprising: a housing with an internal flow passage having an inlet and an outlet; a primary seat in said flow passage; a cylinder having a central axis; a piston making a sliding, fluid sealed fit in said cylinder, and axially shiftable therein; a primary seal carried by said piston adapted to engage the primary seat and close the flow passage in one axial position of the piston, and to leave it open in another axial position thereof; a probe mounted to said piston and passing through the primary seat, and having a bore extending from the downstream end of the piston to a portion of the probe upstream from the primary seat in all axial positions of the piston; a vent passage extending from the cylinder on the downstream side of the piston to a region of lesser pressure than the pressure supplied to the valve; a poppet valve adapted to open or to close said vent passage, whereby to connect said cylinder to said lesser pressure, or to leave it closed so that the bore conducts supply pressure to said cylinder, thereby shifting said piston to open and to close the flow passage at the primary seat, respectively; a position lock to restrain the poppet valve in its open position until contacted by the piston; a restrictor element slidably fitted to said probe upstream of said primary seal; a spring biasing the restrictor element toward the upstream direction, the restrictor element comprising an annular body adapted to make a variable area orifice in said flow passage downstream from the free end of the probe; an annular deflector surface on said piston surrounding and adjacent to said primary seal to direct fluid laterally from said primary seal; and a concave peripheral groove in the outer wall of the piston of lesser lateral extent than the deflector surface.

Claim 9

A valve according to claim 6 in which the position lock is a ball-detent mechanism.

Claim 10

A valve according to claim 6 in which an axially adjustable element is threaded to the piston to adjustably determine the position occupied by the piston when it contacts the position lock.

Claim 11

A valve according to claim 6 in which a counterbore is formed in the flow passage upstream from the primary seat with which the restrictor element cooperates to form said variable orifice.

Claim 12

A valve according to claim 9 in which said restrictor element has a tapered outer surface which narrows as it extends in an upstream direction.

Claim 13

A valve according to claim 10 in which an axially adjustable element is threaded to the piston to adjustably determine the position occupied by the piston when it contacts the position lock.

Claim 14

A valve according to claim 11 in which the position lock is a ball-detent mechanism.

Claim 15

A valve according to claim 12 in which a push button is provided adjacent to the poppet valve to abut and open the same when pressed.

Claim 16

A valve according to claim 13 in which the housing is formed of two parts which are rotationally joined to each other, the outlet being formed in one of said parts and opening into the housing laterally relative to the axis of the cylinder.

Claim 17

A valve according to claim 14 in which the cylinder is formed within a neck in said housing, said neck extending axially into a cavity into which the outlet opens, there being a second deflector surface at the upstream end of said neck.

Claim 18

A valve according to claim 15 in which a restrictor valve is disposed upstream of the probe to limit flow through the valve.

Claim 19

A valve according to claim 15 in which fins are disposed on the probe to maintain it in alignment.

Claim 20

In a valve of the class having a housing with an internal flow passage having an inlet and an outlet thereto, with a primary seat therein, a piston carrying a primary seal to engage said primary seat, a cylinder in which said piston is reciprocable, the piston being movable toward and away from the primary seat to close or to open the valve, respectively, the improvement comprising: an axially shiftable poppet valve so disposed and arranged as to open or to close thereby to vent the cylinder or to close it, and a position lock having a ball-detent mechanism adapted to restrain the poppet valve in its open position until contacted by the piston.

Claim 21

In a valve of the class having a housing with an internal flow passage having an inlet and an outlet thereto, with a primary seat therein, a piston carrying a primary seal to engage said primary seat, a cylinder in which said piston is reciprocable, the piston being movable toward and away from the primary seat to close or to open the valve, respectively, the improvement comprising: an axially shiftable poppet valve so disposed and arranged as to open or to close thereby to vent the cylinder or to close it, and a position lock having a ball-detent mechanism adapted to restrain the poppet valve in its open position until contacted by the piston.