FR2811734A1 - FITTINGS DEVICE - Google Patents

Abstract

Improved valves for disc compressors with adjustable stroke. Valve device for regulating the modification of the stroke of adjustable stroke disc compressors, such as nutating disc compressors or inclined disc compressors with variable stroke, in which to modify the stroke the stroke is regulated. pressure in the engine space, in which a first connection (2) from the high pressure zone (3) to the pressurized zone (4) of the engine space and possibly a second connection (5) from the zone (4) ) under pressure from the engine space to the suction pressure zone (6) can be influenced, characterized in that the first connection (2) can be influenced by a first valve element (8) ) and the second connection (5), by a second valve element (11), the first valve element (8) and / or the second valve element (11) being essentially free of leaks in the state closed. The invention applies in particular to the regulation of the flow rate of nutation disc compressors and inclined disc compressors.

Description

The invention starts from a valve device for regulating the

  modification of the stroke of nutation and inclined disk compressors with variable stroke, in which, in the case of modifiable stroke compressors of this type, the pressure in the engine space is regulated. In the case of known compressors, there is created a connection from the high pressure area to the pressurized area of the engine space and a connection from the pressurized area of the engine space to the suction area, these connections can be

  influenced by throttles or valves.

  The object of the invention is to create an improved valve device

  in the case of disc compressors with changeable stroke.

  This is achieved by means of a valve device for regulating the modification of the adjustable stroke disc stroke, such as nutation disc compressors or inclined variable stroke disc compressors, in which to change the stroke is regulated the pressure in the engine space, in which a first connection from the high pressure area to the pressure area of the engine space and optionally a second connection from the pressure area of the engine space to the pressure area d can be influenced, in which the first connection can be influenced by a first valve element and the second connection, by a second valve element, the first valve element and / or the second valve element being essentially

free from leakage in a closed state.

  A valve device is preferred which contains two valve elements and can have three switching positions, a first switching position connecting the high pressure area with the pressure area of the engine space and locking the pressure area of the engine space with respect to the suction pressure area, a second switching position locking the high pressure area with respect to the engine space pressure area and connecting the space pressure area

  motor at suction pressure area and a third switch position

  tation separating both the high pressure area from the pressurized area

  engine space than the pressure area of the engine space with the suction pressure area. A valve device in accordance with

  the invention there causes the lowest possible loss of flow for regulating

  compressor lation. In the case of a preferred valve device, the valve elements are seat valve elements and may

  be operated by an operating mechanism, as a regulating element.

  A valve device is also preferred in which, in addition, as a safety mechanism, a targeted leak can be provided from the high pressure zone to the pressurized zone of the engine space, in order to guarantee, in the event of failure of the control circuits a safe operating condition by pivoting the return compressor as well as an oil return from

of the high pressure area.

  A tap device is also preferred in which the mechanism

  The operating mechanism can take three stable switching positions, one on the right, one on the left and one in the middle. We propose

  furthermore a valve device in which two of the

  1 5 mutation, in particular the right switching position and the left switching position, can be obtained by means of a reversible, remote-controlled force, while the middle switching position is obtained by restoring forces , like elastic forces. According to the invention, a

  valve device contains an operating mechanism with an electro-

  magnet. In the case of a preferred valve device, the electromagnet consists of a permanent magnet armature and a coil which can be

  traversed by a direct current whose poles can be reversed if necessary.

  There is also a valve arrangement in which the mechanism

  maneuvering nism can be represented by mechanical elements, such as for example bellows and / or throttles and springs and / or others

  electrical, hydraulic or pneumatic components.

  According to the invention, in the case of a ventilation device, the mechanism

  maneuver can maneuver periodically. In the case of another provision

  advantageous faucets, a control circuit for the operation of the operating mechanism uses for the control circuit a measurement of

  pressure as one of, possibly, multiple input signals.

  In addition, a valve device is preferred in which the electro-

  magnet can have a single coil or a double coil. According to the invention

  Also in the case of a valve device, the operating mechanism has a switching time of <20 ms and the switching can

  be done at the rate of this switching time even in per-

  nent. In addition, the invention provides a valve device in which the valve device allows rapid pivoting, back and forth, of the

  disc in the event of water hammer and interventions on the regulation.

  It is also preferred to cool the valve device by the coolant coming from the suction channel, by appropriate guidance of the

  refrigerant through the valve, by mounting the device

  tif tap either on the housing in the area of the suction channel or in the housing, so that it is surrounded, over a large portion, by fluid

  refrigerant from the suction side.

  The invention is described using the Figures which follow on examples of

preferred achievement.

  - Figure 1 shows the valve in a first switching position A. - Figure 2 shows the same valve in a second switching position B. - Figure 3 shows the valve in a third switching position C, which corresponds to the middle position of the

valve device.

  In FIG. 1, the valve device, in the switching position A, authorizes the arrival of the coolant under high pressure in the engine space. In zone 1 of the compressor body, a connection 2 leads from side 3 of the compressor under high pressure to the engine space. Similarly in the right half of Figure 1, a link 5 leads from the engine space 4 to

  side 6 under suction pressure. In an obviously 7 oriented trans-

  versally with respect to the connection 2 is arranged, with freedom of movement, a valve element in the form of a piston 8 which is pushed by a spring 9 against a permanent magnet frame 14. On the right side of the

  Figure I are arranged in a space 10 arranged transversely relative to

  port to the link 5, a valve element in the form of a second piston 1 1 and a spring 12, the piston 1 1 being, in this position, urged to come

  with its front edge in a tap seat 1 7 and therefore to be sealed hermetic-

  only the pipe 5. The armature 14 of the permanent element is located in another recess 13 disposed inside a coil 15. In this representation, the coil 15 is traversed by a direct current which creates a magnetic field so that the permanent magnet passes into the left end position shown here and is therefore pushed to come with a collar 18 against a stop 19. This leads to the fact that the permanent magnet 14 maintains the piston 8 in a position opening against the spring 9 so that the compressor fluid can flow into the engine space via the connection 2 going from the high pressure side 3 to the engine space 4 passing through an annular slot 21 , which leads to an increase in the pressure in the engine space and therefore to a pivoting, in return, of the disc in the direction of a smaller stroke of the compressor. The characteristic of this opening can also, rather than by the annular groove 21 shown here, be formed at will otherwise. What is important above all for this valve device according to the invention is that an appropriately modifiable opening can be made for the flow of the pressurized fluid and that in the closed state those of the elements of taps that are closed operate a hermetic seal, without leakage. The recess 13 in which the permanent magnet armature moves, is closed, to the right, by a second stop 20 which corresponds to the surface of the collar 18. On the right side of the armature 14 of the permanent magnet is can see a slot 16 between the right surface of the permanent magnet armature and the piston 1 1 closed, so that the spring 12 can push the piston 1 I into the seat 1 7

giving a secure seal.

  Figure 2 shows the same valve device in a

  second switching position B, in which the fluid flow

  engine space manager on the suction side is authorized. On this representation

  the same parts are again designated by the same references. In this switching position, the coil of the magnet 1 5 is traversed by a direct current with poles reversed with respect to Figure 1, which leads to the fact that the armature of the permanent magnet 14 now moves in direction opposite and that the collar 18 is pushed against the stop 20. The armature of the permanent magnet now acts on the piston 11 against the force of the spring 12 and the flow of the fluid under pressure can flow from the motor space 4 towards the suction side 6, which leads to the fact that the pressure drops in the motor space and that the compressor disc pivots in the other direction. In this position, the connection 2 on the high pressure side 3 to the engine space 4 is hermetically sealed by the fact that the piston 8 is on its seat 23. Between the piston and the armature of the permanent magnet is

  a slot 24 and the force of the spring 9 pushes the piston 8 on its seat 23.

  Figure 3 shows the valve device according to the invention in a third position C in which the coil is not traversed by the current. The armature of the permanent magnet 1 4 is held there in a middle position by the two springs 9 and 12 by means of the pistons

  8 and l 1. It is important that between the armature of the permanent magnet and the

  tones 1 1 and 8 there is sufficient clearance (which is not shown in the drawing) so that the two pistons 8 and 1 1 can provide a hermetic seal on their respective seats 23 and 17 and that this valve device is therefore absolutely leak-free, which is necessary for regulating the angle of

  disc swiveling with low flow loss.

  In the event of a necessary modification of the pivoting angle of the disc, the current is generated in an appropriate manner, by means of a regulation circuit, by the coil 15. It can also be envisaged as a mechanism for safety for the regulating valve device a constant throttle 24, shown here in Figure 3 on the left in the form of a narrow channel in part 1 of the body, which, even in the event of failure of the regulating valve device or the associated regulation circuit, allows a certain flow of the coolant from the high pressure side 3 towards the engine space 4 and therefore a pivoting, in return, of the pivoting disc to come into the minimum position, as well as a continuous return of the oil from the high pressure area. But we could also consider a mechanism

  of this type in the form of a small additional choked section

  shut machined in the geometrical characteristics of the seat or of the piston 8, which leads to the fact that this piston can no longer then provide a hermetic seal. We can consider an implementation of this security mechanism

  in the form of grooves, grooves or other flow sections.

  One can also imagine that the control of the two pistons 8 and 11 ensuring a hermetic seal could be done by means of a regulating mechanism, remote-controlled, produced in any other way and whose

  structure corresponds to the function, described here, of the permanent magnet armature

  nent and direct current coil. One can imagine there all forms of force mechanisms working in remote control like bellows,

  hydraulic or pneumatic mechanisms, which, through choke-

  elements and springs, exert appropriate forces on the pistons or

  electrical elements of other type, such as for example electro-

  two coil magnets. Compared with currently known regulation strategies, an essential aim of the invention is to give the lowest possible loss of flow for the regulation of a compressor of this type, which is in particular achieved by hermetically sealing the three pressure zones mentioned. Furthermore, this embodiment of the invention saves costly constructions of packings as known.

  in the case of known valves with bellows and electro-

  valves in the state of the art.

  Another advantage of the invention is that it does not possibly require any separate throttling holes, holes which, for example with diameters of 0.2 mm, are sensitive to dirt. Through sections of

  valves can be ordered very quickly, in the case of this provision

  It is also possible to quickly tap the compressor back and forth in the event of water hammer, to obtain a low intervention on the flow rate and to modify the mass flow rate. By means of a periodic operation of the extreme switching positions, the pressure of the engine space can, with an appropriate regulator, be regulated so that this regulation can give stable positions of the pivoting disc. Thanks to the design of the valve elements in the form of seats, an efficiency improvement of 610% can be expected compared to valves with

  drawer that have a corresponding gas leak. The commu-

  A ventilation device of this type is preferably worth 20 ms or less and can optionally be used in operation with pulse width modulation.

Claims (14)

  1. Faucet device for regulating the modification of the stroke of adjustable-stroke disc compressors, such as nutation disc compressors or inclined variable-stroke disc compressors, in which to change the stroke of the disc, the pressure in the engine space, in which a first connection from the high pressure area to the pressure area of the engine space and optionally a second connection from the pressure area of the engine space to the pressure area of suction can be influenced, characterized in that the first connection can be influenced by a first valve element (8) and the second connection, by a second valve element (11), the first element   valve (8) and / or the second valve element (11) being essential-   Leak-free when closed.   2. valve device according to claim 1, characterized in that the valve device contains two valve elements and can have three switching positions, a first switching position connecting the high pressure zone (3) with the zone (4) under pressure from the engine space and locking the area (4) under pressure from the engine space with respect to the suction pressure area, a second switching position locking the area under high pressure (3) by relative to the pressure area (4) of the engine space and connecting the pressure area (4) of the engine space to the suction pressure area and a third switching position separating the high pressure area as well (3) with the area (4) under pressure from the engine space as the area   (4) under pressure from the engine space with the suction pressure area.   3. valve device according to claim 2, characterized in that the valve elements (8, 1 1) are elements of seat valves and can be operated by an operating mechanism as a regulating element.   4. Valve device according to claim 3, characterized in that, in addition, as a safety mechanism (24) can be provided a targeted leak from the high pressure area to the pressure area of the engine space for , in the event of failure of the control circuits, guarantee a safe operating state by pivoting the return compressor as well as   return of oil from the high pressure area.   5. valve device according to claim 2, characterized in that for the regulation of the compressor there is a loss of flow most weak possible.   6. Valve device according to claim 3, characterized in that the operating mechanism can take three stable switching positions, a position on the right, a position on the left and a middle position.   7. Valve device according to claim 3, characterized in that two of the switching positions, in particular the right switching position and the left switching position, can be obtained by means of a reversible force, remote-controlled, while the middle switching position is obtained by restoring forces, like elastic forces.   8. Valve device according to claim 7, characterized by the   causes the operating device to contain an electromagnet.   9. A valve device according to claim 8, characterized in that the electromagnet contains a permanent magnet armature (14) and a coil (15) which can be traversed by a direct current, the   poles can be reversed if necessary.   10. Valve device according to claim 7, characterized in that the operating mechanism can be represented by mechanical elements, such as for example bellows and / or throttles and   springs and / or other electrical, hydraulic or pneumatic components.   1 1. valve device according to one of the preceding claims,   characterized by the fact that the operating mechanism can operate periodically.   12. Valve device, according to one of the preceding claims,   characterized by the fact that a control circuit for the operation of the operating mechanism uses for the control circuit a measurement of   pressure as one of, possibly, multiple input signals.   13. Valve device according to one of the preceding claims,   characterized in that the electromagnet can have a single coil or a double coil.   14. Valve device according to one of the preceding claims,   characterized by the fact that the operating mechanism has a switching time of <20 ms and that the switching can be carried out at the rate of   this switching time, even in continuous operation.   1 5. Valve device according to one of the preceding claims,   characterized by the fact that the valve device allows rapid swiveling back and forth of the disc in the event of water hammer and of interventions on regulation.   16. Valve device according to one of the preceding claims,   characterized by the fact that the valve device is validly cooled by a suction-side refrigerant, to protect the coils and the magnets contained therein.