Automatic regulating valve apparatus

• US 6,263,905 B1
• Filed: 04/06/1999
• Issued: 07/24/2001
• Est. Priority Date: 10/08/1996
• Status: Expired due to Term

• Current Assignee: Kabushiki Kaisha Yokota Seisakusho
• Original Assignee: Kabushiki Kaisha Yokota Seisakusho
• Inventors: Yokota, Hiroshi, Yokota, Shingo
• Primary Examiner(s): RIVELL, JOHN A
• Application Number:
  US09/284,057
• Time in Patent Office: 840 Days
• Field of Search: 137/485, 137/486, 137/487, 137/488, 137/492, 137/501, 137/413, 137/414, 137/423
• US Class Current: 137/413
• CPC Class Codes: F16K 31/363 the fluid acting on a piston F16K31/38 takes precedence
• CPC Class Codes: G05D 16/028 Controlling a pressure difference control of flow G05D7/00
• CPC Class Codes: G05D 16/166 using pistons within the main valve
• CPC Class Codes: G05D 7/03 with auxiliary non-electric power G05D7/005 takes precedence
• CPC Class Codes: G05D 9/04 with auxiliary non-electric power
• CPC Class Codes: Y10T 137/7371 Fluid pressure
• CPC Class Codes: Y10T 137/7404 Plural floats
• CPC Class Codes: Y10T 137/7769 Single acting fluid servo
• CPC Class Codes: Y10T 137/7788 Pressures across fixed choke

Abstract

An automatic regulating valve apparatus comprises a main valve unit, and a pilot valve unit operatively connected to the main valve unit to control the main valve unit. The main valve unit comprises a main valve casing, a main valve element disposed in the main valve casing, and a main valve driving member disposed in the main valve casing together with the main valve element and having a pressure receiving area greater than that of the main valve element, the main valve element is disposed on the upstream side of a valve seat so as to form a restricting passage between the main valve element and the main valve seat, and the main valve driving member is disposed for sliding movement in a space defined by a cylindrical wall formed in the main valve casing so as to define a main valve driving pressure chamber together with the cylindrical wall. The pilot valve unit comprises pilot valves A and B which are operated for opening and closing operations according to the variation of a pressure difference across an orifice included in the main valve unit, a pressure difference across the main valve unit, liquid level on the downstream side of the main valve unit or the pressure on the upstream side of the main valve unit. The pilot valve A and the pilot valve B are arranged in series and connected between the upstream and the downstream side of the main valve unit by connecting passages with a chamber between the pilot valves A and B connected to the main valve driving pressure chamber. The pressure in the main valve driving pressure chamber is varied by the coordinated operations of the pilot valves A and B to regulate the opening of the main valve unit. Thus, the automatic regulating valve apparatus 4 exercises automatic control functions including a constant-flow control function, an emergency shutoff function, a liquid level control function and an upstream pressure control function.

Claims

1. An automatic regulating valve apparatus comprising:

a main valve unit and a pilot valve unit operatively connected to the main valve unit to control the main valve unit,

wherein the main valve unit comprises a main valve casing, a main valve element disposed in the main valve casing, and a main valve driving member disposed in the main valve casing together with the main valve element and having a pressure receiving area greater than that of the main valve element, the main valve element is disposed on an upstream side of a valve seat so as to form a restricting passage between the main valve element and the main valve seat, the main valve driving member is disposed for sliding movement in a space defined by a cylindrical wall formed in the main valve casing so as to define a main valve driving pressure chamber together with the cylindrical wall, a restrictor is disposed in a passage extending through the main valve unit;

the pilot valve unit comprises a pilot valve A and a pilot valve B which are operated by a balance of counteracting forces respectively produced by a pressure difference across the restrictor and a fixed-pressure applying member, the pilot valve A opens when the pressure difference across the restrictor rises above a predetermined level and closes when the same drops below the predetermined level, the pilot valve B closes when the pressure difference across the restrictor rises above the predetermined level and opens when the same drops below the predetermined level; and

the pilot valve A and the pilot valve B are arranged in series and connected between the upstream and the downstream side of the main valve unit by connecting passages with a chamber between the pilot valves A and B connected to the main valve driving pressure chamber; and

wherein a valve element is further provided, said valve element being capable of closing when liquid level on the downstream side of the main valve unit rises above a predetermined level and of opening when the same falls below the predetermined level, and placed in series in a connecting passage connected to the pilot valve B.

2. The automatic regulating valve apparatus according to claim 1, wherein the restrictor is of a variable type.

3. An automatic regulating valve apparatus comprising:

a main valve unit and a pilot valve unit operatively connected to the main valve unit to control the main valve unit,

wherein the main valve unit comprises a main valve casing, a main valve element disposed in the main valve casing, and a main valve driving member disposed in the main valve casing together with the main valve element and having a pressure receiving area greater than that of the main valve element, the main valve element is disposed on an upstream side of a valve seat so as to form a restricting passage between the main valve element and the main valve seat, the main valve driving member is disposed for sliding movement in a space defined by a cylindrical wall formed in the main valve casing so as to define a main valve driving pressure chamber together with the cylindrical wall, a restrictor is disposed in a passage extending through the main valve unit;

the pilot valve unit comprises a pilot valve A and a pilot valve B which are operated by a balance of counteracting forces respectively produced by a pressure difference across the restrictor and a fixed-pressure applying member, the pilot valve A opens when the pressure difference across the restrictor rises above a predetermined level and closes when the same drops below the predetermined level, the pilot valve B closes when the pressure difference across the restrictor rises above the predetermined level and opens when the same drops below the predetermined level; and

the pilot valve A and the pilot valve B are arranged in series and connected between the upstream and the downstream side of the main valve unit by connecting passages with a chamber between the pilot valves A and B connected to the main valve driving pressure chamber; and

wherein a valve element is further provided, said valve element being capable of closing when liquid level on the downstream side of the main valve unit rises above a predetermined upper limit and of opening when the same falls below the predetermined lower limit, and placed in series in a connecting passage connected to the pilot valve B.

4. An automatic regulating valve apparatus comprising:

a main valve unit and a pilot valve unit operatively connected to the main valve unit to control the main valve unit,

wherein the main valve unit comprises a main valve casing, a main valve element disposed in the main valve casing, and a main valve driving member disposed in the main valve casing together with the main valve element and having a pressure receiving area greater than that of the main valve element, the main valve element is disposed on an upstream side of a valve seat so as to form a restricting passage between the main valve element and the main valve seat, the main valve driving member is disposed for sliding movement in a space defined by a cylindrical wall formed in the main valve casing so as to define a main valve driving pressure chamber together with the cylindrical wall, a restrictor is disposed in a passage extending through the main valve unit;

the pilot valve unit comprises a pilot valve A and a pilot valve B which are operated by a balance of counteracting forces respectively produced by a pressure difference across the restrictor and a fixed-pressure applying member, the pilot valve A opens when the pressure difference across the restrictor rises above a predetermined level and closes when the same drops below the predetermined level, the pilot valve B closes when the pressure difference across the restrictor rises above the predetermined level and opens when the same drops below the predetermined level; and

the pilot valve A and the pilot valve B are arranged in series and connected between the upstream and the downstream side of the main valve unit by connecting passages with a chamber between the pilot valves A and B connected to the main valve driving pressure chamber; and

wherein a pilot valve C is further provided, said valve C being operated by a balance of counteracting forces respectively produced by a pressure difference across the main valve unit and a fixed pressure applying element, capable of closing when the pressure difference across the main valve unit rises above a predetermined level and of opening when the same drops below the predetermined level;

a first float valve capable of closing when liquid level on the downstream side of the main valve unit rises above a predetermined upper limit and of opening when the same drops below the predetermined upper limit; and

a second float valve capable of closing when the liquid level on the downstream side of the main valve unit rises above a predetermined lower limit and of opening when the same drops below the lower limit; and

wherein the pilot valve C and the first float valve are placed in series in a connecting passage connected to the pilot valve B, and the main valve driving pressure chamber is connected through the second float valve to the downstream side of the main valve unit.

5. An automatic regulating valve apparatus comprising:

a main valve unit and a pilot valve unit operatively connected to the main valve unit to control the main valve unit,

wherein the main valve unit comprises a main valve casing, a main valve element disposed in the main valve casing, and a main valve driving member disposed in the main valve casing together with the main valve element and having a pressure receiving area greater than that of the main valve element, the main valve element is disposed on an upstream side of a valve seat so as to form a restricting passage between the main valve element and the main valve seat, the main valve driving member is disposed for sliding movement in a space defined by a cylindrical wall formed in the main valve casing so as to define a main valve driving pressure chamber together with the cylindrical wall, a restrictor is disposed in a passage extending through the main valve unit;

the pilot valve unit comprises a pilot valve A and a pilot valve B which are operated by a balance of counteracting forces respectively produced by a pressure difference across the restrictor and a fixed-pressure applying member, the pilot valve A opens when the pressure difference across the restrictor rises above a predetermined level and closes when the same drops below the predetermined level, the pilot valve B closes when the pressure difference across the restrictor rises above the predetermined level and opens when the same drops below the predetermined level; and

the pilot valve A and the pilot valve B are arranged in series and connected between the upstream and the downstream side of the main valve unit by connecting passages with a chamber between the pilot valves A and B connected to the main valve driving pressure chamber; and

wherein a pilot valve D is further provided, said valve D being operated by a balance of counteracting forces respectively produced by a pressure difference across the restrictor and a fixed pressure applying element, capable of opening when the pressure difference across the restrictor rises above a predetermined level and of closing when the same drops below the predetermined level;

a first float valve capable of closing when liquid level on the downstream side of the main valve unit rises above a predetermined upper limit and of opening when the same drops below the predetermined upper limit; and

a second float valve capable of closing when the liquid level on the downstream side of the main valve unit rises above a predetermined lower limit and of opening when the same drops below the lower limit;

wherein the pilot valve D and the first float valve are placed in series in a connecting passage connected to the pilot valve B, and the main valve driving pressure chamber is connected through the second float valve to the downstream side of the main valve unit.

6. The automatic regulating valve apparatus according to claim 5, wherein three valve elements of the pilot valves A, B and D are disposed coaxially so as to move together according to the balance of the counteracting forces produced by the pressure difference across the restrictor and the fixed-pressure applying means.

7. An automatic regulating valve apparatus comprising a main valve unit and a pilot valve unit operatively connected to the main valve unit to control the main valve unit;

wherein the main valve unit comprises a main valve casing, a main valve element disposed in the main valve casing, and a main valve driving member disposed in the main valve casing together with the main valve element and having a pressure receiving area greater than that of the main valve element, the main valve element is disposed on an upstream side of a valve seat so as to form a restricting passage between the main valve element and the main valve seat, the main valve driving member is disposed for sliding movement in a space defined by a cylindrical wall formed in the main valve casing so as to define a main valve driving pressure chamber together with the cylindrical wall;

the pilot valve unit comprises a pilot valve A and a pilot valve B operated by a balance of counteracting forces respectively produced by a pressure difference across the main valve unit and a fixed-pressure applying means, the pilot valve A is capable of opening when the pressure difference across the main valve unit rises above a predetermined level and of closing when the same drops below the predetermined level, the pilot valve B is capable of closing when the pressure difference across the main valve unit rises above the predetermined level and of opening when the same drops below the predetermined level, the pilot valves A and B are arranged in series and connected between the upstream and the downstream side of the main valve unit by connecting passages with a chamber between the pilot valves A and B connected to the main valve driving pressure chamber;

a first float valve capable of closing when liquid level on the downstream side of the main valve unit rises above a predetermined upper limit and of opening when the same drops below the predetermined upper limit, and a second float valve capable of closing when the liquid level on a downstream side of the main valve unit rises above a predetermined lower limit and of opening when the same drops below the lower limit are employed; and

the first float valve is placed in series in a connecting passage, connected to the pilot valve B, and the main valve driving pressure chamber is connected through the second float valve to the downstream side of the main valve unit.