Interlocking sequence valve for liquid fuel

Claim 2

A pressure-operated check valve comprising: a valve body, open at both ends, having a central passage communicating between the ends, and provided with a fuel inlet port, a fuel outlet port and control port which is adapted to be connected to a pressure source, all ports opening into the central passage; a piston assembly, including a piston, coaxial with an mounted for slidable movement within the central passage of the body between open and closed positions, in the closed position, the assembly providing a seal between the inlet and outlet ports, while in the open position, the assembly permitting flow between the inlet and outlet ports; said piston assembly being exposed to and responsive to variations in the pressure at the control port to control the positioning of the piston assembly; a biasing means urging the piston assembly into a closed position until the pressure at the control port exceeds a predetermined level; a diaphragm, disposed across the central passage between the fuel inlet and outlet ports, which is unbroken when the piston assembly in in the closed position; and a rupturing means connected to the piston assembly for rupturing the diaphragm when the piston assembly moves to the open position.

Claim 3

The check valve of claim 1, in which the seal between the inlet and outlet ports is effected by an O-ring mounted on the piston.

Claim 4

a hollow section having an intermediate outside diameter and a shoulder where it joins the section having a small outside diameter, the shoulder serving to limit the motion of the piston assembly in the fully open position, the section having slots through the wall structure; the two hollow sections, having the same inside diameter, communicating with the fuel inlet port:

Claim 5

a hollow section having an intermediate outside diameter and a shoulder where it joins the section having a small outside diameter, the shoulder serving to limit the motion of the piston assembly in the fully open position, the section having slots through the wall structure; the two hollow sections, having the same inside diameter, communicating with the fuel inlet port:

Claim 6

two solid sections having a larger outside diameter than the hollow sections, including those sections of the piston which include the O-rings; and

Claim 7

two solid sections having a larger outside diameter than the hollow sections, including those sections of the piston which include the O-rings; and

Claim 8

The check valve of claim 1, in which the biasing means is a compression spring mounted about the piston.

Claim 9

The check valve of claim 1, wherein the rupturing means is a knife.

Claim 10

a necked-down section between the two solid sections, having a diameter approximately equal to the inside diameter of the hollow sections, the central passage adjacent this section communicating with the fuel outlet port; the width of the sections being so proportioned that, when the piston assembly is in the closed position, there is no communication from the fuel inlet port, through the two hollow sections, to the fuel outlet port, but in the open position there is such communication through the slots and the necked-down section of the piston.

Claim 11

a necked-down section between the two solid sections, having a diameter approximately equal to the inside diameter of the hollow sections, the central passage adjacent this section communicating with the fuel outlet port; the width of the sections being so proportioned that, when the piston assembly is in the closed position, there is no communication from the fuel inlet port, through the two hollow sections, to the fuel outlet port, but in the open position there is such communication through the slots and the necked-down section of the piston.

Claim 12

The check valve of claim 1, wherein: the valve body includes: a support, including the fuel inlet port, adapted to be attached to a fuel tank; a cap connected to the support; a housing, including the fuel outlet port and the control port, and connected to the cap; the support, cap and housing having the central passage communicating therethrough; and wherein the diaphragm is fixed in place, and before rupturing, closes the central passage between the sUpport and the cap; and wherein the piston assembly is located in the central passage of the housing and cap.

Claim 13

The check valve of claim 1, further comprising: another fuel inlet port wherein the flow of fuel through both fuel inlet ports is controlled by the pressure at the control port.

Claim 14

A pressure-operated check valve comprising: a valve body, open at both ends, having a central passage communicating between the ends, and provided with a fuel inlet port, a fuel outlet port and a control port which is adapted to be connected to a pressure source, all ports opening into the central passage; the valve body comprising: a housing, including the fuel outlet port at a central portion thereof and the control port at a first end thereof; a cap, connected to the housing at a second end thereof, the central passage through the cap constituting the fuel inlet port, the cap serving to limit motion of the piston assembly in the fully open position; a piston assembly coaxial with and mounted for slidable movement within the central passage of the body between open and closed positions, in the closed position, the assembly providing a seal between the inlet and outlet ports, while in the open position, the assembly permitting flow between the inlet and outlet ports; said piston assembly being exposed to and responsive to variations in the pressure at the control port to control the positioning of the piston assembly; the piston assembly comprises: a piston; an O-ring mounted on the piston near the control port, which serves to confine the pressure from the pressure source to the first end of the valve housing irrespective of the position of the piston assembly; and a biasing means urging the piston assembly into a closed position until the pressure at the control port exceeds a predetermined level.

Claim 15

A pressure-operated check valve comprising: a valve body, open at both ends, having a central passage communicating between the ends, and provided with a fuel inlet port, a fuel outlet port and a control port which is adapted to be connected to a pressure source, all ports opening into the central passage; the valve body comprising: a housing, including the fuel outlet port at a central portion thereof and the control port at a first end thereof; a cap, connected to the housing at a second end thereof, the central passage through the cap constituting the fuel inlet port, the cap serving to limit motion of the piston assembly in the fully open position; a piston assembly coaxial with and mounted for slidable movement within the central passage of the body between open and closed positions, in the closed position, the assembly providing a seal between the inlet and outlet ports, while in the open position, the assembly permitting flow between the inlet and outlet ports; said piston assembly being exposed to and responsive to variations in the pressure at the control port to control the positioning of the piston assembly; the piston assembly comprises: a piston; an O-ring mounted on the piston near the control port, which serves to confine the pressure from the pressure source to the first end of the valve housing irrespective of the position of the piston assembly; and a biasing means urging the piston assembly into a closed position until the pressure at the control port exceeds a predetermined level.

Claim 16

The check valve of claim 7, in which the seal between the inlet and outlet ports is effected by another O-ring mounted on the piston.

Claim 17

The check valve of claim 8, further comprising: a diaphragm disposed across the central passage between the fuel inlet and outlet ports, which is unbroken when the piston assembly is in the closed position; and a rupturing means connected to the piston assembly for rupturing the diaphragm when the piston assembly moves to the open position.

Claim 18

The check valve of claim 9, wherein the rupturing means is a knife.

Claim 19

The check valve of claim 9, wherein: the valve body includes: a support, including a fuel inlet port, adapted to be attached to a fuel tank; a cap connected to the support; a housing, including the fuel outlet port and the control port, and connected to the cap; and wherein the diaphragm is fixed in place, and before rupturing, closes the central passage between the support and the cap, and wherein the piston assembly is located in the central passage of the housing and cap.

Claim 20

The check valve of claim 7, further comprising: another fuel inlet port wherein the flow of fuel through both fuel inlet ports is controlled by the pressure at the control port.

Claim 21

The check valve according to claim 11, wherein the piston further comprises the following cylindrical sections: