Normally closed three-port valve

Patent metadata

Field	Value
Publication number	US-9435445-B2
Application number	US-201214439029-A
Country	US
Kind code	B2
Filing date	Oct 30, 2012
Priority date	Oct 30, 2012
Publication date	Sep 6, 2016
Grant date	Sep 6, 2016

Abstract

A normally closed three-port valve includes a valve member urged from a supply port side toward a main valve seat of a valve body in a valve closing direction and opened by a valve opening rod having a discharge channel. A back pressure chamber at a back of the valve member communicates with a channel on an output port side through a vent hole balancing fluid pressures acting on front and back surfaces of the valve member. The valve member includes a main body, a seat member, a securing member, and a pressing frame The seat member includes an elastic discoid sealing member, main and discharge seat surfaces, and communication holes open at a region between the main and discharge seat surfaces forming the vent hole. The securing member secures the seat member to the valve member main body. The pressing frame is at the circumference of the seat member.

First claim

The invention claimed is:

1. A normally closed three-port valve includes a valve member urged in a valve closing direction by a return spring from a supply port side toward a main valve seat provided in a valve body between an output port and the supply port; a discharge channel provided into a valve opening rod which makes the main valve seat open by applying a valve opening operating force to the valve member, and the discharge channel closed by bringing the rod into contact with a discharge seat surface on the valve member; and a balance mechanism configured to balance the fluid pressure acting on front and back surfaces of the valve member by providing a vent hole in the valve member when the valve member is at a valve open position, and the vent hole allowing a back pressure chamber of a back of the valve member to communicate with a channel for a main fluid on the output port side,
wherein the valve member comprises a valve member main body that is slidably held in a contacting and separating direction relative to the main valve seat and has a through hole formed therein to form the vent hole, a seat member that is formed of a discoid sealing member having rubber elasticity, that brings into contact with a main valve seat facing surface of the valve member main body, that has a main seat surface at a portion facing the main valve seat, that has the discharge seat surface formed at a portion facing an end surface of the discharge channel of the valve opening rod, and that has a communication hole allowing the through hole of the valve member main body to be open at a region between the main seat surface and the discharge seat surface, a securing member that is airtightly fitted into a central portion of the seat member so that a tip end thereof is locked in the valve member main body so as to secure the seat member to the valve member main body, and a pressing frame that holds a circumference of the seat member on the valve member main body, and
wherein respective members are formed by molding.

2. The normally closed three-port valve according to claim 1 ,
wherein the pressing frame that holds the circumference of the seat member on the valve member main body has a locking edge portion locked at the circumference of the seat member and the locking edge portion which clamps the seat member between the circumference of the valve member main body and the locking edge portion, and wherein a circumferential edge lower portion of the pressing frame, which is in contact with a circumferential edge of the valve member main body, is secured to the valve member main body by welding or bonding.

3. The normally closed three-port valve according to claim 1 ,
wherein a tip end of the valve opening rod applying the valve opening operating force to the valve member projects from the valve body to an outside, so that an outer end of the rod serves as a contacting end that is in mechanical contact with a valve operating mechanism.

4. The normally closed three-port valve according to claim 1 ,
wherein, in the main valve seat facing surface of the valve member main body, a groove that allows the communication hole provided corresponding to the region between the main seat surface and the discharge seat surface of the seat member of the valve member to communicate with the through hole of the valve member main body.

5. The normally closed three-port valve according to claim 1 ,
wherein, in the main valve seat facing surface of the valve member main body, a projection is inserted into the communication hole provided corresponding to the region between the main seat surface and the discharge seat surface of the seat member of the valve member and positions the seat member, and the projection suppresses narrowing of the communication hole due to deformation.

Assignees

• Smc Corp

Inventors

• Kuribayashi Akira
• Yamamoto Hitoshi

Classifications

• F16K11/04

  comprising only lift valves · CPC title

• F16K1/36 Primary

  Valve members (for double-seat valves F16K1/44 {; for butterfly valves F16K1/222, F16K1/223}) · CPC title

• F16K39/02 Primary

  for lift valves · CPC title

• F16K11/06 Primary

  comprising only sliding valves {, i.e. sliding closure elements} · CPC title