DE1220009B - - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. Cl .:

HOIh

German class: 21c-35/10

Number: 1220 009

File number: A 46451 VIII d / 21 c

Filing date: June 29, 1964

Opening day: June 30, 1966

Heatable gas pressure switches are already known. The compressed gas, e.g. B. SF ₆ gas, circulates there in a closed circuit system. This circulatory system consists of a low-pressure tank, a high-pressure tank and a compressor. The compressed gas from the compressor is fed to the high-pressure container, in each case when the temperature of the compressed gas in the high-pressure container falls below a certain level or when the gas pressure in the high-pressure container has dropped too far. When the high-pressure gas falls below a certain temperature, the gas pressure difference between the high-pressure and the low-pressure container decreases and a bimetal valve is activated. As a result, a pressure relay responds and activates the compressor, which feeds the gas heated by the compression to the high-pressure container. This process results in an undesirably long delay before the correct operating temperature is restored. The invention avoids these disadvantages by making it possible to work with a small pressure difference and a short time delay.

The invention relates to a pressurized gas switch with a circulation system for the pressurized gas, consisting of a high pressure tank, a low pressure tank and a compressor, the sucks in relaxed compressed gas from the low-pressure container and transfers it to the high-pressure container with overpressure feeds again.

The invention consists in that the high-pressure container is complete and the low-pressure container is partially thermally insulated that pressure relief valves from the high pressure tank to the low pressure tank it is provided that the compressor is followed by a heating element and that for switching the compressor and the heating element relays are provided, one of which is dependent on the pressure of the gas in the high pressure vessel, one of the temperature of the gas in the high pressure vessel and one of the Switch-off command to the switch is dependent.

The invention is explained in more detail using an exemplary embodiment:

In Fig. 1, 1 denotes a single-pole compressed gas switch with two switching points la. The switching points are located in the switching chambers 3. The switching chambers are connected to the high-pressure container 4. The switching chambers are housed in the low-pressure container. Through the pipe 2 a low-pressure tank is connected with the low pressure side of the compressor. 8 The high pressure side of the compressor is connected to the high pressure container via the pipeline 8 α. In this pressurized gas switch with a circulatory system for
the compressed gas

Applicant:

Public company Brown, Boveri & Cie.,

Baden (Switzerland)

Representative:

Dr.-Ing. E. Sommerfeld, patent attorney,

Munich 23, Dunantstr. 6th

Named as inventor:

Dipl.-Ing. Egbertus Adrianus Frowein,

Nussbaumen (Switzerland)

Claimed priority:
Switzerland of June 10, 1964 (7582)

The compressor sucks in expanded compressed gas from the low-pressure container and feeds this back to the high-pressure tank with overpressure. The high pressure container is by means of a Heat insulating layer 5 completely thermally insulated. The low pressure tank is not closed by a Thermal insulation layer 24 partially thermally insulated. Overpressure valves 7 are attached to the switching chambers 3, which allow an outflow of the compressed gas to the low-pressure container when the gas pressure difference exceeds a specified value in the two containers.

The compressor 8 is followed by the heating element 9 via the pipes 8 α and Aa. This consists of the pipe coil 9 a, to which the heating coil 9 b is applied. The heating element 9 is used to increase the temperature of the compressed gas after leaving the compressor in a certain prescribed manner. Gas pressure meter ρ and temperature sensor t in the high-pressure container 4 are used to keep the pressure and the temperature of the compressed gas at a certain operating value. When the heating coil is switched on, the compressed gas is heated before it enters the high-pressure container.

It can be advantageous to install a bypass parallel to the pipe coil 9a of the heating element.

609 587/322

3 4

Line to be arranged, which to keep the shut-off valve 10 on- element as low as possible. A cheap-

shows. When the shut-off valve 10 is open, the compromise flows through the following measure

Most of the compressed gas from the compressor reaches:

The low-pressure container 2 is partially with

Bypassing the heating element, when 5 is closed, a thermal protection 24 insulates, to the extent that

Shut-off valve all pressurized gas flows from the grain - that at the highest occurring ambient

pressor through the heating element. Pressing the temperature reduces the heat loss of the current-carrying

Shut-off valve is carried out by means of a switching magnet, parts of the switch are cut off from the environment.

10 α through the relay P and through the relay S. For will give. This ensures that the prescribed,

the control of the compressor and the heating current do not set the maximum temperatures for these parts

for the heating element and possibly the switching exceeded. The heating output is through this

solenoids of the shut-off valve, the actuating relay measure is reduced to a minimum.

T, P, S provided. Relay T with the temperature According to a further embodiment of the invention

Sensor t works as a function of the temperature is shown in Fig. 2 in the direction of flow of the gas

of the gas in the high pressure container, relay P with 15 a cooler 22 and parallel to it a bypass

the pressure meter ρ depending on the pressure of the line with a shut-off valve 23 is provided.

Gas in the high-pressure container and relay S when the shut-off valve 23 is operated except

Issue the switch-off command to the switch. through the pressure relay and the Sehaltreläis

The interconnection of the relays T, P and S with additionally by a relay T ₁ , which is dependent on the Tempedem compressor or with the heating coil 9 b and ao temperature of the gas in the low-pressure container of the heating element 9 is done in such a way that further is the N Each pressure vessel with only the following cooperation results: If the partially existing heat insulation 24 is provided. Temperature of the gas in the high-pressure container to.
and the heating element 9. The possibly existing 35 The mode of operation of the arrangement according to F ig, 2 shut-off valve 10 is closed. is the following:

This is fueled gas in the high- _First . _{Too low TeniperatlH} . of the gas
pressure tank pumped causing pressure there and _{in the} high pressure tank
Temperature rise. When a predetermined pressure in the high-pressure container is exceeded, the temperature relay T responds, the compressor 8 then the pressure relief valves 7, and it is set in motion, the bridging valve 10 gas circuit is closed and the heating element 9 is switched on

High pressure tank ^ Overpressure valves - Low - ^The shut-off valve 23 is open The compressor

pressure chamber - Compressor heating element- ** »& ^gas *» the low pressure tank 2 an ^ utid

High pressure ^{tank 3} S WPP * ^{es un} ^ ^r bypassing the cooler 22 through the

Heating element 9 in the pressurized container 4, The

a. This is maintained until the heated gas heats this container and the switch required The temperature of the gas in the high-pressure chamber 3 rises and then escapes through the excess space is reached again. As a result of this directly on pressure valves 7 in the low pressure tank, the the temperature in the high-pressure chamber reacting 40 is also warmed up at the same time. From there flows Control is the set temperature in the high pressure the gas back to the compressor 8. The heating room restored in no time. The process continues until the desired temperature is reached

If a lowering of the high pressure tank is achieved due to internal leakage losses and the relay T

of the gas pressure in the high-pressure container enters, drops,

the P-relay responds. This causes the compression to 45 Second: Too high temperature in the

Sor m operation set and the line valve 10 low pressure tank
opened, whereupon the compressor bypassed

of the heating element 9 the high pressure space in the shortest possible time. The temperature relay T ₁ responds, which brings the comm time to the required setpoint pressure. When presser 8 is set in motion, and the shut-off switch-off command is given to the Sehaltstellen 50 valve 23 is closed. The cooler 22 is effective and so to extinguish the arc from the sam, the shut-off valve 10 is open, and the yeast high-pressure container 4 or the switching chambers 3 element 9 is bypassed.

through the contacts of the contact points, which "jet" The compressor sucks in gas that is too hot from the Are designed like, pressurized gas in the low pressure Niederdruekbehälter 2 and pumps it through the container flows, is with the recharging of the 55 cooler 22 in the high pressure container 4 and the Hochdrupkbehälters not waited until the pressure in the switching chambers 3- After the gas left the cooler 22 this container has sunk so far that it has left, it is on approximate ambient P-relay responds It is cooled down by the switch-off temperature and at the same time cools the current command S-relay actuated directly, which direct parts of the Sehalters. Due to the overprintable turns on the compressor, 60 valves 7 it gets into the low pressure tank, where

When the stop command is over, it has meanwhile had a cooling effect, and then flows

the pressure in the high-pressure tank has dropped so far back to the compressor.

gen that the P relay has responded. This cooling process is maintained for so long

Relay takes over control of the compressor until the temperature in the low-pressure container

and the shut-off valve until the target pressure in the high 65 has reached the desired value again and that

pressure vessel is restored. Relay T ₁ drops out.

In the system according to Fig. 1, efforts will be made to determine the effect of the system on internal pressures.

the total heating output of the compressor and heating losses in the high-pressure space or containers, the

Response of the relays P and S is the same as that of the system in FIG. 1 described.

It is clear that the additional cooling of the current-carrying switch parts with the gas circulation described can only take place as long as the gas that the high pressure container and thus the switching chambers is supplied, has a temperature which is higher than the permitted temperature of the Gas in the high pressure container to avoid condensation.

Below this temperature, the cooling system cannot be used and the heat generated by the current-carrying parts of the switch is generated, on the uninsulated part 24 α of the low-pressure tank transmitted to the environment.

In the arrangement according to FIG. 2, the low-pressure container so insulated that at an outside temperature slightly higher than the specified minimum temperature of the pressurized gas in the high-pressure container, the current-carrying parts dissipate their heat loss via ao can release the uninsulated part of the low-pressure tank to the environment without the regulation exceed the specified maximum temperature for these parts. Because the specified minimum temperature of the high-pressure gas is far below the highest ambient temperature, a significantly larger part of the low-pressure tank are thermally insulated than in the case of the arrangement according to FIG. 1. The heating power to be used in the system according to FIG. 2 significant less.

At an outside temperature at which the switch must be heated, the heat generated is the Live parts dissipated by the natural cooling. When the outside temperature is higher Depending on the current load, additional cooling of these parts may be required.

Seen as a whole, the insulation of the low-pressure container achieves that at low ambient temperatures the heating power and the running time of the compressor are greatly reduced. If the ambient temperature is high, the compressor must run for a certain time in order to achieve additional cooling of the live parts.

Depending on the climatic conditions, a suitable choice of the ratio of the heat-insulated area to the uninsulated area of the low-pressure tank a minimum of annual output of the compressor.

Claims (3)

Patent claims: 1. Compressed gas switch with a circulatory system for the compressed gas, consisting of a high pressure container, a low pressure container and a compressor, which sucks in the expanded compressed gas from the low pressure container and supplies it with excess pressure to the high pressure container, characterized in that the high pressure container (4) is completely and the low pressure container ( 2) is partially thermally insulated, that pressure relief valves (7) are provided from the high-pressure container (4) to the low-pressure container (2), that the compressor (8) is followed by a heating element (9) and that for switching the compressor (8) and the heating element (9) Relays (P, T, S) are provided, one of which (P) depends on the pressure of the gas in the high-pressure container, one (T) on the temperature of the gas in the high-pressure container and one (S) on the switch-off command to the switch . 2. Compressed gas switch according to claim 1, characterized in that in a bypass line a shut-off valve (10) operated by a switching magnet (10 a) is arranged for the heating element (9) is. 3. Compressed gas switch according to claim 1, characterized in that the compressor (8) in the flow direction of the compressed gas, a cooler (22) is connected downstream and that a shut-off valve operated by a switching magnet (23 a) (23) is present in a bypass line parallel to the cooler (22). 1 sheet of drawings 609 587/322 6.66 ® Bundesdruckelei Berlin