DE1038361B - Pressure control or Locking device - Google Patents

Description

GERMAN

There are known pressure regulating and locking devices in the line of a flowing medium, wherein the closure piece is coupled to a membrane and in the space between the membrane and the closing piece is the supply pressure of the medium, on the other side of the closing piece the consumption pressure of the medium and on the other side of the membrane there is a control pressure. Changes in the supply pressure affect due to the large surface area of the membrane compared to that of the spanking piece to a large extent the consumption pressure, which is not or not always sufficient Dimensions of the control pressure can be compensated. For this reason, this is made from the closure piece and diaphragm existing system is relieved by the fact that the exposed to the supply pressure Surfaces can be made the same size.

The invention relates to such a pressure regulating or locking device in the line of a flowing medium, the medium being equal to the space between two coupled membranes large effective surface flows through and with a control force on the outer side of the one membrane and a counter pressure is effective on the outer side of the other membrane. With such an execution Both the control force and the counter pressure are supplied by mechanical means, bellows and spring.

The aim of the invention is to create a device of this type which responds to small adjustment forces and yet is able to precisely control a medium at high pressure. As a field of application the regulation of propane for heating purposes is mentioned. The calorific value of propane is S to 6 times that as large as that of town gas, and the line pressure is about 5 times as high. This makes the application a Control valve with a smaller diameter necessary.

According to the invention, the medium is now located on the outer side of the other membrane under the regulated or final pressure, and it exerts the counter pressure there by the fact that this membrane with a valve seat with an internal closure piece is provided, which is provided with a fixed stop cooperates, which pushes the closure piece when the membrane moves from its seat.

It is essential for the device according to the invention that the gas from the line first the Must flow through space between the two membranes. In the previously known devices was this is not the case. Rather, the gas flowed in through a line, and the gas flowed out this line was z. B. controlled by a piston valve. This slide becomes the piston itself Pressure regulating or locking device

Applicant:

ASW Apparatenfabriek NV,
Nijmegen (Netherlands)

Representative: Dr. W. Germershausen, patent attorney,
Frankfurt / M., Neue Mainzer Str. 49/51

Claimed priority:
Netherlands 6 October 1954

Willem Albertus van Kreuningen,

Nijmegen (Netherlands),
has been named as the inventor

adjusted, while the piston sleeve is also axially adjustable. Both adjustments are made by membranes. These membranes are not coupled together, as is essential to the invention. Yet It is more important that the membranes in the known device only under the already regulated down Pressure stand while it is essential to the invention is that the membranes are under the unregulated admission pressure.

In another known device, the unregulated gas pressure flows to which is then regulated so that the membrane is only under the regulated gas pressure. Located between the two membranes just another derived pressure. The fresh gas does not flow through the space between the two membranes.

The invention is explained with reference to the drawing. In this drawing a device is according to the invention shown schematically in cross section.

After passing through a tap (not shown), the gas to be regulated comes via line 1 into space 2 between membranes 3 and 4, which are clamped in housing 5. The supply pressure p _{v of} the medium thus prevails in space 2. The membranes 3 and 4 are coupled with rigid rods 6 or the like, which do not constitute an obstacle to the gas flow.

A small part of the gas is discharged directly from the space 2 via the line 7. These Amount of gas is fed to an opening, the size of which depends on the passage opening to be regulated.

809 600/2 * 1

3 4

The opening is shown schematically at 8. It becomes the minimum pressure p _r . The task is therefore to be controlled by a closure piece 9, which ensures that the valve 18, 19 closes when p _{r is} worn at 10 articulated arm 11. reached this minimum value. This can be done with this arm 11 from the bimetal element 12 around screw 25 at the end of the stop 20. Ground pivot point 10 pivoted. According to the invention, this bimetallic element further utilizes the fact that element 12 is determined by the temperature in the room, that when the pressure p _r drops, the force with which sets which is heated by the gas to be regulated. the locking piece 19 rests on the stop 20, too - of course, the locking piece 9 can also take from one.

a variable other than the room temperature. Gradually falling control pressure p _s results in the. The opening 8 merges into the line 15, an excess of force upwards, so that the membranes which are raised against a constant counter pressure and the passage cross section blows. In the present case, this line runs in through the valve 18, 19 is smaller and p _r decreases, a burner nozzle 16 from where a pilot flame, the stop 20 may be such branding with the screw 25, will be provided, that in the case p _s = 0 Control pressure p _r ge

The pressure in the line 15 corresponds to the adjustment 15 rade has the value to reduce the gas consumption to ¹ U des

ment of the closure piece 9 and thus the controlled variable to keep full consumption.

ie in this case the room temperature. Assuming that the weight of the room temperature to be moved is the same as the opening 8 wide open membrane system then exactly that of the control and if the pressure in the line 15 is almost the same as the pressure exerted, the force must be high like the supply pressure p _v . Via the line 17 20 effective surfaces of the membranes 3 and 4, the pressure in the line 15 will be - with p _s to be just equal, so that the pressure p _{v has} a resulting - control pressure in the space above the aunt zero . It is taken into account that membrane 3 is guided. the upper membrane is curved upwards, whereby

The lower membrane 4 is provided in the middle with its effective surface when lifting, while valve seat 18, which is arched downward in the space 22 rend the lower membrane 4, together with a spherical closure piece 19 so that their effective surface when lifting. This works with a stop 20 takes. So there is a position when lifting, together. When the membrane 4 bends downwards through which the two effective surfaces bend against each other, the closure piece 19 leaves the valve seat 18, and the force exerted by the gas pressure p _v so that the gas from the space 2 into the space 21 over- 30 between the two membranes can flow out onto the system. From this space 21 is practiced over which is equal to zero. This is the location, which line 22 tapped the consumption gas and z. B. achieved when adjusting the stop 20 at p _s = 0 is fed to a burner 24. The pressure in the room is, because when the gas consumption is set to ¹ U 21, the consumption pressure, which here at the same time as p _r, just reaches such a value that the force of counter and control pressure for the membrane system fun- 35 the pressure p _r das Weight of the moving parts measured and can be referred to as p _T. equals.

If the control pressure p _{r is} below the lower membrane. If p _v should now vary somewhat, this results in bran 4 being smaller than the control pressure p _s , so there is no difficulty in moving, because the influence of the pressure p _v causes the membranes 3 and 4 to move downwards ; the passage through the equally large effective membrane upper cross-section between the closure piece 19 and the 40 surfaces is balanced. If p _v increases with a larger seat 18, and p _{r increases} until the open position of the valve 18, 19 changes, then the same value as p _s results, apart from its own weight which varies in the same respect moving parts. The burner pressure p _r , which then ensures that the work through, so for full consumption. If the passage cross-section at the valve 18, 19 is higher, but room temperature is set, the valve 8, 9 is closed and 45 is closed until the required pressure p _{r is} achieved,
thus also p _s = 0, and the diaphragms go according to. The stop 20 can now be designed to be resilient at the top, the passage cross-section between the locking piece 19 and the seat 18 decreasing so that it elastically descends from the locking piece 19. That can be pressed. The valve 18, 19 is exposed to the pressure p _r then decreases to such a value, difference in the pressures p _v and p _r , that the weight of the moving parts is balanced 50 which the latter is the lower. Which will; the burner 24 burns low. takes force resulting from this pressure difference

For safety reasons, however, the gas may be closed when the closure piece 19

need not be lowered further than until ¹ U of its seat 18 approaches.

full consumption, because otherwise the flame standing on the burner would go out too easily due to the selection of the spring for the flame. The stop 20 is set up in such a way that if p _r the smallest value of the gas consumption can still reach a minimum value - at ¹ U of the maximum gas consumption still bring about too high a room temperature, while needing - the force mentioned on the closure end on the other hand, the outside temperature again 19 has become just big enough that it does not need to be so high that it can be pressed in without a resilient stop 20. Can get by with heating. The resulting drop in pressure p _s drops p _r because the difficulty can be eliminated by lifting the membrane system and setting up the passage through which the system is such that the gas consumption valve 18, 19 is smaller. By lowering the is only reduced to ¹ U of the full pressure p _r increases the need on the locking piece 19 and, if this would still be too high, pressing force so that the resilient stop 20 is immediately completed. Until ¹ U of the maxi- 65 is pressed in a little further. This leads to a reduction in gas consumption, so there is a uniform reduction in the passage cross-section of the control valve, and below this minimum gas consumption 18, 19, which initially decreases p _r , but the control is required by in and out this in turn leads to a downward movement of the shift is achieved. The gas consumption of ¹ A of the full membrane system and thus to a restoration of power naturally corresponds to a certain 70 of the pressure p _r and to a new equilibrium.

However, it should be taken into account that the membrane system does not sink as far as it would theoretically be the case with the same size and constant membrane surfaces, because when lowering the effective surface of the upper membrane 3 increases and that of the lower membrane 4 decreases. This means that p _r has become somewhat lower in the new position, and this increases the downward force on the locking piece 19, so that the resilient stop 20 is pressed in further than one would expect if p _{T remained the same.}

There is thus a relative movement of the locking piece 19 and the seat 18 towards one another, and because this leads to a further reduction in the pressure p _r , this movement is progressive, which means that as soon as the resilient stop 20 is pressed in a little, the closure piece 19 also reaches the seat 18 completely and thus the gas supply is immediately terminated. As I said, it is ensured that this takes place when p _{r reaches} a desired minimum value.

If then p _A begins to rise again, the membranes 3 and 4 are pressed down. The pressure p _{v then} holds the closure piece 19 against the stop 20 and thus also decreases. In this case, however, the spring which supports the stop is tensioned and its force reaches such a value that the locking piece 19 is pushed off by the stop 20 and snaps back into its original position. An equilibrium is then established anew, p _r is higher than before because p _{s has} now become greater than 0.

If the device described above is adapted to a burner 24 with a smaller opening, but is used for a burner with a larger opening, the pressure p _r , whereby the valve 18, 19 is opened, corresponds to a larger passage cross-section and thus to a lower position of the membranes 3 , 4. The effective surface of the lower diaphragm 4 is then smaller and that of the upper diaphragm 3 is larger, so that p _v provides an upward force excess which is compensated for by a greater pressure p _s. In other words, the opening of the valve 18, 19 then does not take place at p _s = 0, but before the zero value is reached.

Claims (4)

Patent claims. 1. Pressure control or locking device for a flowing medium, which the room effective surface of the same size flows through between two coupled membranes, whereby a control force on the outer side of one membrane and a control force on the outer side of the other A back pressure is effective, characterized in that on the outer side of the membrane other membrane (4), the medium is under the regulated or ultimate pressure and there the Counterpressure is exerted in that the membrane (4) has a valve seat (18) with an internal closure piece (19) is provided, which cooperates with a fixed stop (20) which pushes the closure piece (19) off the seat (18) when the membrane (4) moves. 2. Apparatus according to claim 1, characterized in that the stop (20) in the direction the center line of the valve (18,19) is adjustable. 3. Apparatus according to claim 1 or 2, characterized in that the stop (20) in the direction the center line of the valve (18,19) is resilient. 4. Apparatus according to claim 3, characterized in that the stop (20) is arranged in such a way and its suspension is chosen such that the closure piece (19) at a predetermined Value of the pressure difference between the supply pressure and the regulated final pressure of the Completes the medium. Considered publications:
German Patent No. 368 015;
Swiss Patent No. 217 578;
Dutch patent specifications No. 10 648, 53 836. 1 sheet of drawings © 809 600 / 2S1 9.5 &