DD288667A5 - ARRANGEMENT FOR MONITORING THE DENSITY OF A GAS - Google Patents

Abstract

The invention relates to an arrangement for monitoring the density of a gas in a hermetically sealed container, in particular for electronegative gases as filling medium in electrical switchgear. With the arrangement of a possible high maintenance-free operating time is to be made possible even if small leaks occur in the container. In particular, it should have a high level of safety against consequential damage during failures. For this, the arrangement should be such that it is intrinsically safe. It can be achieved that even if one of the hermetic pressure systems fails, information and / or shutdown of the system will occur immediately. At the same time, the prevention of gas density losses due to temperature compensation should be avoided. For this purpose, the interior of a first metal bellows is connected via a first capillary tube with a arranged in hermetically sealed container Fuehler, wherein the filling medium in the sensor, in the capillary, in the interior and in the container is the same and the interior of a second metal bellows via a second capillary with the hermetically sealed container is connected. Between both Metallbaelgen is a Stoeszel, on which an electrical switch is arranged, which is electrically connected to a solenoid valve, which is arranged in a located between the hermetically sealed container and a Vorratsbehaelter line. At Stoeszel a double switch is further arranged, wherein the Einschaltkontakt is closed by the first switching element of the double switch when the stroke of the Stoeszels in the direction of the bellows connected to the metal bellows exceeds a vorjuristierbaren limit and the Einschaltkontakt is closed by the second switching element of the double switch, if the stroke of the Stoeszel in the direction of the bellows connected to the bellows a pre-adjustable limit exceeds. FIG {monitoring; Density; electronegative gas; electrical switchgear; Temperature compensation; metal bellows; intrinsically safe arrangement}

Description

Metallbalges (12) a pre-adjustable limit is exceeded,

- The Einschaltkontakt (30) by the second switching element (29) of the double switch (26) is closed when a vorjustierbarer limit is exceeded by the stroke of the plunger (3) in the direction of the container (16) connected to the metal bellows (1).

Field of application of the invention

The invention relates to an arrangement for monitoring the density of a gas in a hermetically sealed container according to the preamble of the claim.

Characteristic of the known state of the art

In electrical switchgear, it is often expensive to surround the switchgear with an electronic gas to ensure proper operation. To avoid disturbances or dangers, the density of the

A solution described in DE-DS 314274B provides a special gas detector for controlling the density of the electronegative gas. In this case, a container, which preferably consists of a below a predetermined internal pressure standing, double-sided gas-tight sealed bellows, housed in the switchgear, wherein the position of the container bottom in densityÄ nderungun the electronegative gas for density change display in the longitudinal direction of the container is variable. The container bottom int at an adjustable distance from an outer stop underrides.

are formed, wherein the interior of the first metal bellows is connected via a first capillary tube with a temperature sensor arranged in the hermetically sealed container and the interior of the second metal bellows is connected via a second unsealed capillary with the hermetically sealed Behält. Ov \\ sX the VvANvneÄxvivftNTvVjeNAe'rtNQescVvue'öeTveTxii'ivicV.svsXemen g \ e \ cr \ to achieve emperaturVompensation and thus to avoid simulating gas density losses . In conjunction with a solenoid operated by an electric switch, it is also possible to compensate for gas density losses from a reservoir. In both described solutions, it is disadvantageous that they have no intrinsic safety, ie, that there is no information or shutdown of the system in case of failure of the hermetic temperature compensation system , as despite a gas density loss within the system a proper degree of filling is faked.

Object of the invention

The object of the invention is to monitor the temperature of the gases of the gas. It is necessary to monitor the gas content of the fuel gas It is possible, in particular, to ensure a high degree of security against consequential damage own in case of failures.

Dattagung desWesens the invention

The invention has for its object to design an arrangement for monitoring the density of a gas in a hermetically sealed container so that d ^! o whole arrangement is intrinsically safe. It can be achieved that it also in case of failure of the hermetic temperature compensation system for information or immediately to a shutdown of the

Plant comes to report consequential damage. According to the invention the object is achieved in that a double switch is arranged on the plunger, wherein the

E \ nscha \\ kon \ aV. \ Is closed by the yoke of the opepe maya \ s, the hub of the sxossis pointing towards the mW connected to the febAer, and the threshold limit If the stroke of the plunger in the direction of the metal bellows connected to the container exceeds a pre-adjustable limit value, the decision is made that the second switching element of the double switch exceeds and is closed.

With the invention, it has been possible to carry out the arrangement for monitoring the density of a gas intrinsically safe in a simple manner. As soon as one of the two pressure systems formed by the metal bellows fails, an exceeding of the previously adjusted limit stroke and thus by actuation of one of the two switching systems results in an information or a fv.bschaU.en the fvniage.

embodiment

The invention will be explained below with reference to the drawing of an embodiment. The single FIGURE shows a schematic representation of the arrangement according to the invention.

The arrangement initially comprises a sealed on one side Malallbelag 1, on the closed end face 2, a plunger 3 is supported. At the plunger 3 is a driver 4, through which a switch 7 is actuated by a direction indicated by a double arrow 5, introduced via the Motallbalg 1 longitudinal movement of the plunger 3 via a shift lever 6. Furthermore, located on the plunger 3 a DoppelscbaUer 26, whose switching elements 28; 29 actuate a switch 30. In this case, the position of the switch-on of the Einschaltkontaktes 30 by changing the position of the switching elements 28; 29 adjustable on the plunger 3 . The turn-on contact 30 is electrically connected to a display 31 serving the information. Furthermore, on the plunger 3 a z. B. by means of threaded axially displaceable and thus adjustable in its initial position EinsteiUeiler 9, on whose the Metalibaig 1 opposite end face 13 a differential pressure spring 8 is applied, which in turn is supported on a stationary stop 10. The axial movement of the adjustment plate 9 is limited towards the NieXaiibaio, \ dutch a stationary Knschiag AA

The metal bellows 1 facing away from the end of the plunger 3 abuts against the closed end face 11 of a metal bellows 12 closed on one side.

All the details mentioned so far are located in a housing 15, which is advantageously located outside of a hermetically sealed container 16 which is filled with an electronegative gas 17 to ensure the function of therein located, not shown electrical switchgear.

The housing 15 has an unillustrated Sichlfenster in which on the basis of a scale, the set by means of the adjustment plate 9 allowable variation of the density of the electronegative gas 17 can be read. In the container 16, a sensor 18 is arranged, which is connected via a capillary 19 with the interior 20 of the otherwise hermetically sealed metal bellows 12. A second Kapia / Iarrohrleitung 21 Tingt with one end / n the inner space 22 of the metal bellows 1, while the other end protrudes into the container 16.

The sensor 18, the Ysapiilarrohrieitungen 19; ΪΛ and the interiors 20; 22 of the two Nietalibälge A ; \ 2 are mix the same e \ eY.Vtoneo, aWvenC3as M vj \ e of fceftäWer AB a, e \ u \\\, where the YüWdrucYAm by ÜÜY \\ "" Vfc.VA ^ WauohtWWvmo , λθ \ ind 20 formed thermally sealed system is preferably equal to the filling pressure of the container 16. The container 16 is connected via a line 23 to a reservoir 24, wherein in the conduit 23, a solenoid valve 25 is arranged, which is electrically connected to the switching contact 27th of the switch 7 is connected.

The operation of the arrangement can be easily read from the schematic diagram showing the arrangement in case of failure of the pressure system formed by the metal bellows 12 of the capillary 19 and the sensor 18. Thus, if the density of the efektronegativen gas T 7 located in the container 16 begins within a range that can be detected by the setting plate 3 , the entire arrangement is in equilibrium when other pressure systems are hermetically sealed. Occurring temperature fluctuations are compensated by the metal bellows 12, which is under the action of the sensor 18.

When density losses occur, the pressure in the container 16 and thus also in the interior 22 of the metal bellows 1 decreases until the switch 7 is actuated by the occurring movement of the plunger 3 via the driver 4 and the shift lever 6. By closing the switching contact 27, the actuation of the solenoid valve 25, whereby the stored under higher pressure in the reservoir 24 electronegative gas 17 so long into the container 16 so long, until the required density value is reached again, so that the switching contact 27 is opened.

For example, in the case of a leakage of the metal bellows 12, there is a failure of this eyelet system, so that a density loss in the container 16 would no longer be corrected. Therefore, as soon as the stroke of the plunger 3 exceeds a pre-adjustable limit value, the switch-on contact 30 is closed via the switching element 28, and one, in this case visual information about the display 31. In the case of the other pressure device, for example by a failure of the solenoid valve 25 or by an additional reservoir 24

but this time in the opposite stroke direction, exceeds the vorjusVierbaren limit.

Claims (1)

Arrangement for monitoring the density of a gas in a hermetically sealed container, the - Two opposing separate pressure systems, the two pressurized spaces through the respective interior of a metal bellows on a first The interior of the first metal bellows is connected via a first capillary tube to a sensor arranged in the hermetically sealed container, and the liquid medium in the vicinity of the capillary tube, in the space and in the container g \. e \ ch is, • DevVrmerwaum des zv> je \\. ErvMö \ .a \ Vaa \ ges via e \ ttwox \ teV <Ap \\ auoV \ T \ e \\ unQrc \\\. is connected ctercvYvBtrrveWacYv abgeschJossenen container, - a is arranged between the two pressure systems plunger with a cam for actuating an electrical switch, which is connected to a solenoid valve which is arranged in an opening located between the hermetically sealed vessel and a reservoir pipe, - Has a arranged between the driver and a pressure system differential pressure spring, characterized in that on the plunger (3) a double switch (26) is arranged, wherein - The switch-on (30) by the first switching element $ R \ Ooopelschalters $ & \ closed