AUTOMATIC PUMP SHUTDOWN CIRCUIT

• US 3,814,542 A
• Filed: 06/30/1972
• Issued: 06/04/1974
• Est. Priority Date: 06/30/1972
• Status: Expired due to Term

• Current Assignee: Edmundo J. Iglesias, Robert Mayer
• Original Assignee: Edmundo J. Iglesias, Robert Mayer
• Inventors: Mayer, Robert, Iglesias, Edmundo J.
• Primary Examiner(s): Freeh, William L.
• Application Number:
  US05/267,769
• Time in Patent Office: 704 Days
• Field of Search: 243/4 417/12,42 302/35
• US Class Current: 417/12
• CPC Class Codes: B65G 51/08 Controlling or conditioning the operating medium
• CPC Class Codes: F04B 49/02 Stopping, starting, unloading or idling control

Abstract

In response to a sustained drop in the vacuum in a pneumatic line, a circuit automatically shuts down the vacuum pump (which is coupled to the line) for a short interval, and then restarts the pump.

Claims

1. In combination, a vacuum pump normally operating to produce a partial vacuum in a line, a vacuum switch operated to the closed position in response to a decrease in the vacuum in said line to below a preset value, a first time delay relay connected in series with said switch and operating its contacts at the end of a first time interval, said relay having a pair of contacts which when operated act to shut down said pump;

and a second time delay relay connected in series with said switch and operating its contacts at the end of a second time interval, said second relay having a pair of contacts which when operated act to start said pump.

2. Combination of claim 1, wherein said second time interval exceeds said first time interval.

3. Combination of claim 1, wherein said second time interval is on the order of 60 seconds, and said first time interval is on the order of thirty seconds.

4. Combination set forth in claim 1, including also electrically energized counter means, said first relay having another pair of contacts which when operated cause energization of said counter means.