Ping Yin Lin

US Patent:

58552243, Jan 5, 1999

Filed:

Jul 11, 1996

Appl. No.:

8/680216

Inventors:

Ping Lin - Bedford MA
Rand Ackroyd - Methuen MA

Assignee:

Watts Investment Company - Wilmington DE

International Classification:

F16K 1500

US Classification:

137527

Abstract:

A check valve assembly mounted for engagement with a valve seat includes a flapper valve and a lever arm. The flapper valve includes a bracket pivotably mounted along a first hemisphere of the valve seat, a valve plate mounted to the bracket along a region generally spaced from a periphery of the valve plate, and a mounting assembly adjustably joining the valve plate to the bracket. The flapper valve has a closed position with the valve plate in sealing engagement with the valve seat about the periphery of the valve plate. The lever arm is pivotably mounted to the valve seat along a second hemisphere of the valve seat opposite the first hemisphere. The lever arm includes a lever surface disposed for moving contact with an engagement surface of the bracket and a biasing means for biasing the lever surface toward contact with the engagement surface.

US Patent:

60502932, Apr 18, 2000

Filed:

Jan 5, 1999

Appl. No.:

9/225427

Inventors:

Ping Lin - Bedford MA
Rand Ackroyd - Methuen MA

Assignee:

Watts Investment Company - North Andover MA

International Classification:

F16K 1500

US Classification:

137527

Abstract:

A check valve assembly mounted for engagement with a valve seat includes a flapper valve and a lever arm. The flapper valve includes a bracket pivotably mounted along a first hemisphere of the valve seat, a valve plate mounted to the bracket along a region generally spaced from a periphery of the valve plate, and a mounting assembly adjustably joining the valve plate to the bracket. The flapper valve has a closed position with the valve plate in sealing engagement with the valve seat about the periphery of the valve plate. The lever arm is pivotably mounted to the valve seat along a second hemisphere of the valve seat opposite the first hemisphere. The lever arm includes a lever surface disposed for moving contact with an engagement surface of the bracket and a biasing means for biasing the lever surface toward contact with the engagement surface.

US Patent:

55514731, Sep 3, 1996

Filed:

Jan 6, 1995

Appl. No.:

8/369415

Inventors:

Ping Lin - Bedford MA
Anthony L. Arthur - Derry NH

Assignee:

WattsRegulator Company - Wilmington DE

International Classification:

F16K 2402

US Classification:

137218

Abstract:

A fluid flow control valve, e. g. a pressure vacuum breaker, includes a thermal expansion relief valve for protecting the control valve against damage due to freezing. The control valve has a valve body of rigid material and defines a main conduit. The thermal expansion relief valve has a relief valve body mounted to the main valve and defines a relief conduit in fluid communication with the main conduit, a valve element the moves within the relief conduit between a first sealing position in engagement with a valve seat to resist flow and a second position spaced from the valve seat to allow flow from the main conduit through the relief conduit, and a spring urging the valve element toward sealing position with a predetermined force selected to exceed normal operating pressure of the main valve and to lie below pressure damaging to the main valve. A thermal expansion valve for protecting fluid flow control valves, e. g. by retrofit, is also described.