Claims
- 1. A pressure relief manometer comprising:
- a container for liquid;
- a liquid mass in said container;
- first generally upright tube means for containing a first column of said liquid responsive to barometric pressure;
- second generally upright tube means substantially parallel to said first tube means, said second tube means containing a second column of said liquid responsive to pressure variations in a test area;
- said first upright tube means extending into said container below the surface of said liquid and terminating at a terminal opening of said first tube means;
- a portion of said second tube means extending into said container concentrically within said first tube means to a location below said liquid,
- said second tube means terminating at a terminal opening below said terminal opening of said first tube means, and
- selectively openable and closeable vent means communicating with the interior of said container for venting gas pressure within said container.
- 2. The manometer as recited in claim 1, wherein: said vent means included means for selectively connecting said vent means with a source of vaccuum or with atmosphere outside of said container.
- 3. The manometer as recited in claim 1, further including: selectively openable and closeable valve means on said first tube means for isolating said first column of liquid from the outside atmosphere.
- 4. A manometer which comprises:
- a reservoir having a first outlet at a top surface and a second outlet operatively disposed on a side surface;
- a liquid partially filling said reservoir;
- a first tube having a closed top end fixedly positioned in said first outlet and an open bottom end extending into said liquid;
- a second tube of smaller diameter than said first tube having a lower section hermetically sealed to and axially passing through said closed top end of said first tube and extending into said liquid to a depth below said opened bottom end of said first tube;
- a barometric arm having a lower end hermetically connected to same top end of said first tube and communicating therewith and an upper end hermetically connected to an upper section of said second tube;
- a first stop cock valve operatively disposed in said barometric arm intermediate said lower and upper ends of said barometric arm;
- scale means fixedly connected between said second tube and said barometric arm; and
- valve means for alternatively evacuating and pressurizing a space above the liquid level of said liquid in said reservoir.
GOVERNMENTAL INTERESTS
The invention described herein may be manufactured, used and licensed by or for the Government for governmental purposes without the payment to me of any royalties thereon.
US Referenced Citations (2)
Number |
Name |
Date |
Kind |
1582942 |
Thomas |
May 1926 |
|
1918635 |
Cummings |
Jul 1933 |
|