Fluid control valve

• US 4,456,218 A
• Filed: 02/18/1983
• Issued: 06/26/1984
• Est. Priority Date: 01/30/1980
• Status: Expired due to Term

• Current Assignee: Aisin Seiki Co., Ltd. (Aisin Corp.)
• Original Assignee: Aisin Seiki Co., Ltd. (Aisin Corp.)
• Inventors: Kawabata, Yasuhiro, Aoki, Kongo
• Primary Examiner(s): Cohan, Alan
• Assistant Examiner(s): Rivell, John A.
• Application Number:
  US06/467,743
• Time in Patent Office: 494 Days
• Field of Search: 251/61, 251/61.5, 251/63, 251/63.5, 251/63.6, 251/214, 251/324, 123/568
• US Class Current: 251/61.5
• CPC Class Codes: B60H 1/00485 Valves for air-conditioning devices, e.g. thermostatic valves valves per se F16K; thermostatic valves per se G05D23/02
• CPC Class Codes: F16K 31/1262 one side of the diaphragm being spring loaded

Abstract

A fluid control valve actuated by differential pressure across a diaphragm member. The diaphragm member is secured to a piston mounted thereon with a seal ring. The seal ring is in fluid-tight sliding engagement with a casing having an inlet port and an outlet port, but is brought into disengagement from the casing upon movement of the piston due to differential pressure across the diaphragm member. Thus, communication between the inlet and the outlet ports may be accomplished.

Claims

1. A fluid control valve comprising:

a casing having an inlet port and an outlet port,

a cover member rigidly coupled to said casing and including a port member formed therein,

vacuum pressure signal means communicating with said port member formed in said cover member;

a piston slidably mounted in said casing,

first seal ring means mounted on said piston for providing fluid-tight seal between said piston and said casing,

a diaphragm member having an outer periphery portion and an inner periphery portion,

said outer periphery portion being held between said cover member and said casing,

said inner periphery portion being secured to said piston,

a first chamber defined by said piston, said diaphragm member and said cover member, and communicating with said vacuum pressure signals via said port formed in said cover member,

a second chamber defined by said piston, said diaphragm member and said first seal ring means, and in constant communication with atmospheric pressure,

spring means positioned between said cover member and said piston for urging said piston in one axial direction thereof, and

second seal ring means mounted on said piston in fluid-tight sliding engagement with said casing so as to be disengaged therefrom upon axial movement of said piston wherein said first seal ring means further comprises a guide member mounted within said casing, a first seal ring member fluid-tightly mounted between said guide member and said piston and a second seal ring member fluid-tightly mounted between said guide member and said casing and wherein said guide member further comprises a flange portion and said casing further comprises a shoulder portion and an inner groove portion, and further comprising a snap ring positioned in said inner groove portion such that said flange portion is held between said shoulder portion and said snap ring.