Vacuum safety valve

• US 4,070,001 A
• Filed: 07/06/1976
• Issued: 01/24/1978
• Est. Priority Date: 07/06/1976
• Status: Expired due to Term

• Current Assignee: Ronald R. Musgrove
• Original Assignee: Ronald R. Musgrove
• Inventors: Musgrove, Ronald R.
• Primary Examiner(s): Rosenthal, Arnold
• Application Number:
  US05/702,527
• Time in Patent Office: 567 Days
• Field of Search: 251/46, 251/33, 137/DIG. 8, 91/52
• US Class Current: 251/46
• CPC Class Codes: F16K 51/02 specially adapted for high-vacuum installations
• CPC Class Codes: Y10S 137/907 Vacuum-actuated valves

Abstract

A vacuum safety valve comprises a closed cylindrical valve body having one end connected to a system to be evacuated, and a tube extending from the side wall to a vacuum pumping system. The other end of the valve body includes a port connected to ambient air through a solenoid operated valve which is normally open when de-energized. An extendable bellows is secured about the port on the inside of the valve body, and the distal end of the bellows is sealed by a plate having a small bleed hole in the edge thereof. Should the pumping system fail, the solenoid valve is deactuated to open the bellows interior to ambient air. The air pressure expands the bellows and drives the plate against the interior port to seal off the system side of the valve before the vacuum therein is destroyed.

Claims

1. A vacuum safety valve, comprising a valve body having an inlet port and an outlet port, valve seating means disposed about said inlet port on the interior of said valve body, extendable bellows secured within said valve body and including means for engaging said seating means and sealing said inlet port when said bellows means is fully extended;

said valve body including a bellows port communicating with the interior of said extendable bellows and with a valve means which selectively opens to ambient air, said means for engaging said seating means including a plate secured in sealing fashion to the distal free end of said bellows, and further including a bleed port extending from said interior of said bellows through said plate to the peripheral edge thereof, said bleed port extending in constant, limited flow communication between said interior of said valve body and said interior of said bellows.

2. The safety valve of claim 1, wherein said seating means includes an O-ring seal disposed about said inlet port.

3. The safety valve of claim 1, wherein said valve body comprises a cylinder having said inlet port at one end thereof, and said extendable bellows is secured to the interior surface of the other end thereof.

4. The safety valve of claim 3, wherein said bellows port is disposed in said other end of said cylinder.

5. The safety valve of claim 4, wherein said outlet port is disposed in the wall of said cylinder.

6. The safety valve of claim 1, wherein said valve means is closed when actuated, and said extendable bellows is extended only by positive pressure therein introduced through said valve means when deactuated and open.