FR2498697A1 - PRESSURE TRANSMITTER BETWEEN SEPARATE FLUIDS - Google Patents

Abstract

DIFFERENTIAL TYPE PRESSURE TRANSMITTER WITH OPPOSITE BELLOWS. IT INCLUDES A BOX 11 IN WHICH THE TWO INSULATED CHAMBERS 18, 19 OF THE DIFFERENTIAL SYSTEM ARE DEFINED BY A WATERPROOF TRANSVERSE BULKHEAD 34 TO 37 ON WHICH THE BELLOWS 38, 39 ARE MOUNTED AND CONNECTED 46 IN A CLASSIC WAY AND BY TWO BLOCKS 21, 23 MOUNTED ON RESPECTIVE THREADED RODS 30 AND 31 WELDED INTO THE AXIS OF THE OUTER WALLS 24, 25 OF THE HOUSING. THE VOLUME OF THE CAVITY DEFINED AT THE MOVING END 44, 45 OF EACH BELLOWS IS REDUCED BY THE FRONT PART OF THE CORRESPONDING BLOCK AND THE VOLUME OF THE RESPECTIVE CHAMBER IS ALSO REDUCED BY THE REMAINING PART OF THIS BLOCK. APPLICATION AS AN INSULATOR FOR PRESSURE SENSORS OR OTHER DEVICES IN A NUCLEAR INSTALLATION.

Description

The present invention relates to means for transmitting

  pressure mission by two or more separate fluids and, more particularly, an instrument similar to a manometer

differential bellows.

  No. 2,664,749 of January 5, 1954 discloses a differential pressure gauge characteristic of the prior art.

  Insulation devices used in

  to separate pressure sensors or other similar apparatus, in particular for reasons of

  temperature or radioactivity, are described in the

  American vouchers No. 3,696,659 issued October 10, 1972, and

  No. 3,956,937 issued May 18, 1976.

  In the prior art, the liquids expand

  excessively when heated in such devices.

  tive. This causes an excessive elongation of the bellows

sensors.

  According to the device of the present invention,

  disadvantages referred to above or other inconveniences

  disclaimers of the prior art are overcome by reducing the size of each of the two chambers in a stacker, and

  cavities of the bellows in an insulator.

  The invention will be better understood on reading the

  following detailed description, given as an example

  non-limiting with reference to the attached figure which represents a longitudinal sectional view of an insulator

  constructed according to the present invention.

  The figure represents an insulator 10 similar to a

  gusset differential pressure gauge. Insulator 10 has a bot-

  tier II comprising elements 12 and 13 having surfaces

  internal and external cylindrical 14, 15 and 16, 17 respectively

  tively. The surfaces 15 and 17 substantially surround sealed chambers 18 and 19, respectively. Inlets and / or outlets of the chamber 18 are provided in 20

and 21.

  Inlets of entry and / or exit of the room

19 are provided in 22 and 23.

  All exterior structure to surfaces 15 and 17

can be classic.

  Inside the same surfaces, everything can also be conventional, except the end walls 24 and 25 of casings 26 and 27, respectively, plugs 28 and 29, threaded rods 30 and 31, and welds 32 and 33. connecting the rods 30 and 31 to the end walls 24 and

, respectively.

  Parts 34, 35, 36 and 37 form a partition

  tight between rooms 18 and tg.

  The bellows 38 and 39 are each filled with a respective incompressible fluid, the fluid present in one

  being in communication with the one present in the other.

  Conventional bellows stroke limiting valves are provided at 40 and 41; they have O-rings 42 and 43, respectively. For example, see O-rings 31 and 32 in US Patent

  No. 2,632,474 issued on March 24, 1953, and the seats of

popes 29 and 30, respectively.

  The hollow ends 44 and 45 of the bellows 38 and 39, respectively, are fixed relative to one another

  by a rod 46, which is conventional.

  The holes 47 and 48 are large enough to allow the incompressible fluid to flow from the inside of one of the bellows inside the other and vice versa. For the remaining structures see the last mentioned patent. When the pressure in the chamber 18 is higher than in the chamber 19, the bellows 38 tends to compress and the bellows 39 tends to expand. The opposite is also true.

  If the maximum differential pressure is very low

  the elasticity constants of the bellows may be

  negligible. Otherwise, the elastic forces may or may not

  the movements of the bellows before a valve

race limitation does not close.

  Although the differential pressure can be indi-

  it is not essential that it be so.

  One can also provide a switch for a

  alarm, but this is not necessarily necessary.

  An important object of the present invention is to make the pressure in the chamber 18 trigger an organ in communication with the chamber 19, or vice versa, without

  the fluids in the chambers 18 or 19 do not mix.

  See the two aforementioned patents for more utility.

  It is obvious that the foregoing description

  has been made only as a non-limitative example and that other variants can be envisaged without going out for

as much of the scope of the invention.

Claims (3)

  t --- Device sensitive to the action of isomeric fluids   characterized in that it comprises a box (tl) having a central transverse partition (34 to 37) and a first (12) and a second (13) side wall around said box having an opening on each side separation; first (38) and second (39) bellows each having a fixed end sealed around the respective opposing sides of said partition, said first and second bellows respectively having a first (44) and   a second (45) movable closed end comprising respectively   a first and a second cavity, said cavities extending inward towards said separation; a first (28) and a second member (29); first (30) and second means (31) respectively fixing said first   and second elements on said stacker in a decent position   terminated relative to said stacker, said first and second members having respective first and second portions   housing in said first and second cavities, respectively   the first and second parts of the first and second   elements filling most of the volumes of the pre-   first and second respective cavities; and incompressible fluid parts filling each of said bellows and being   in communication with each other.   2 - Device according to claim 1, characterized   characterized in that said casement (1t) has a construction   forming a first (18) and a second chamber (19) in   out of said cavities and out of said first (38) and second (39) bellows, respectively, said first (28) and second (29) members having third and fourth portions, respectively, occupying substantially all of the interior space at the first (18) and the second chamber (19), respectively. 3 - Device according to claim t or 2, characterized in that said casing (1i) comprises first (24) and second (25) end walls which partially define said first (18) and second (19) chambers, respectively , said first and second means (30, 31)   fixing those third and fourth parts of those   first and second elements (28, 29) respectively to said   first and second outer walls, respectively.