Fill limiting filler valve unit

• US 4,064,907 A
• Filed: 09/30/1976
• Issued: 12/27/1977
• Est. Priority Date: 09/30/1976
• Status: Expired due to Term

• Current Assignee: REGO Company
• Original Assignee: REGO Company
• Inventors: Billington, Evans R., Batka, Robert J.
• Primary Examiner(s): Bell, Jr., Houston S.
• Application Number:
  US05/728,038
• Time in Patent Office: 453 Days
• Field of Search: 141/198, 141/18, 141/95, 251/298, 137/446, 137/448, 137/614.2
• US Class Current: 137/614.2
• CPC Class Codes: F16K 31/26 with the valve guided for rectilinear movement and the float attached to a pivoted arm
• CPC Class Codes: F17C 13/021 having the height as the parameter
• CPC Class Codes: F17C 2250/0413 with floats
• CPC Class Codes: F17C 5/02 for filling with liquefied gases
• CPC Class Codes: Y10T 137/7478 With interposed cam, gear or threaded connection
• CPC Class Codes: Y10T 137/88054 Direct response normally closed valve limits direction of flow

Abstract

A high volume filler and automatic fill-limiting valve unit for customer LP Gas dispensing systems in which tandem backflow check valves are opened by incoming replenishing liquid. When a prescribed outage fill level is reached, the inner one of the valves is released from a mechanical restraint of a float control to convert and operate as an inflow check valve which is closed by the incoming flow pressure drop across it to arrest further inflow and permit the outer one of the valves to also close if it is mechanically free to do so. In either case after inflow shutoff the inner valve under spring pressure resumes its normal outflow check valve position to free the float mechanism and independently supplement the backflow check valve function of the outer valve.

Claims

1. A fill limiting filler valve assembly for a liquefied petroleum gas service tank comprising:

a filler valve housing extendable through the wall of a storage tank and pivotally supporting a cam means at the liquid fill limit of the tank and including a normally closed filler backflow check valve for connection to a pressure filler hose in sealed relation and having a valve member coacting with an inlet port to open under inflowing liquid filling pressure;

fill control means having spaced inner and outer open valve ports with a valve chamber between them through which the replenishing liquid flows;

valve means in said chamber including a valve head and valve stem mounted in said housing for reciprocating the valve head in said chamber to obstruct selectively free flow of liquid through said inner and outer ports;

resilient means urging said valve means to open said inner port in the direction counter to the pressurized inflow;

liquid level responsive means including a float pivotally mounted upon said housing and a cam follower on said valve stem coacting with the cam means when the fill level limit of the tank is approached;

said cam means having a cam surface engaged by said follower to hold said valve means in a full flow open position with respect to said inner port during filling operation, said follower moving from said cam surface into the cam relief recess when the fill limit of the tank is reached to permit flow through said inner valve port to be obstructed by said valve head in the direction of flow under inflowing filling pressures;

bleed means for equalizing pressures on opposite sides of said inner valve when closed against its port; and

said resilient means urging said inner valve to open and retract said follower upon equalization of pressures on opposite sides of said inner valve port.

2. The filler valve unit defined in claim 1 in which:

said cam means is engaged by said follower only during the time and backflow check valve is open to hold the inner valve seat open while the fill level is below said fill limit.

3. The filler valve unit defined in claim 1 in which said cam means includes a rotary cam differential which has a substantially radial orientation following a sharp corner graduated enough for inertially retarding vertical load of movement the float means when closing the inlet port to permit closure of the inflow check valve without a hammering.

4. The combination defined in claim 1 in which said inner check valve is a normally closed outflow check valve supplementing said backflow check valve when the latter is closed, and opens under incoming pressure when said latter opens for filling purposes.

5. In a liquefied gas dispensing system:

a customer storage tank having a horizontal opening in the wall thereof at a predetermined fill limit level;

a filler valve unit received in said opening defining in tandem a connection for a filler hose for supplying LP Gas in its liquid phase under pressure above the vapor pressure in the tank and including

a. a normally closed outer backflow check valve disposed downstream of a valve port and normally closing against said port and opening under incoming liquid phase pressure;

b. an inner check valve means reciprocable in a chamber between spaced opposing inlet and outlet ports and defining full flow passage intermediate the opposing ports, said outlet port being in communication with the interior of the tank, means for urging the check valve means to close said inlet port but responsive to pressure in said inlet port for movement to close said outlet port;

c. float means responsive to the level of liquid in the tank for releasably holding said inner check valve means at said intermediate position of its movement for full flow through said opposing ports; and

float controlled means for releasing said inner check valve means to close when said predetermined fill level is reached.

6. The combination defined in claim 5 in which said float controlled means releases said inner check valve means to close its said inlet port.

7. The combination defined in claim 5 including pressure equalizing means interconnecting the tank and said chamber.

8. A filler valve unit comprising a valve housing extending through the wall of a storage tank and pivotally supporting a cam means at the liquid fill limit of the tank comprising:

check valve means having spaced inflow and outflow check valve ports defining a valve compartment betweem them through which replenishing liquid can flow and a valve member for alternately closing said inner and outer ports;

resilient means for urging said valve member to close said inflow check valve port;

liquid level responsive means including a float pivotally mounted upon said housing and a cam follower journaled on said valve stem coacting therewith at the fill level limit of the tank;

said cam means having a cam surface engaging said cam follower to hold said valve member in open position with respect to said inflow and outflow check valve ports for full flow between them and to move across the edge thereof into a recess when the fill limit of the tank is reached;

said cam wall being inclined to the line of movement of said follower to permit said valve member to close against said outflow port under inflowing filling pressures;

means for equalizing pressures on opposite sides of said outflow check valve port; and

spring means urging said outflow check valve to open upon equalization of pressures on opposite sides of said inner valve.

9. A fill limiting filler valve assembly for a liquefied petroleum gas service tank comprising:

a filler valve housing extendable through the wall of a storage tank and pivotally supporting a cam means at the liquid fill limit of the tank and including a normally closed filler valve for connection to a pressure filler hose in sealed relation and having a resiliently closed back flow check valve member opening an inlet port under inflowing liquid filling pressure;

fill control means having an inner valve port with a valve chamber through which the replenishing liquid flows;

valve means in said chamber mounted inside the wall of said housing including a valve head and a valve stem for driving the valve head in said chamber to obstruct flow of liquid through said inner port;

resilient means urging said valve means to open said inner port against pressurized liquid inflow;

liquid level responsive means including a float pivotally mounted upon said housing and a cam follower on said valve stem coacting with the cam means when the fill level limit of the tank is approached;

said cam means having a cam surface engaged by said follower to hold said valve means in a full flow open position with respect to said inner port during filling operation, said follower moving from said cam surface into a cam relief recess to raise the float above its valve release position when the fill limit of the tank is reached to permit flow through said inner valve port to be obstructed by said valve head in the direction of flow under inflowing filling pressures;

bleed means for equalizing pressures on opposite sides of said inner valve when closed against its port; and

said resilient means urging said inner valve to open and retract said follower upon equalization of pressures on opposite sides of said inner valve port.