WO1989012166A1

WO1989012166A1 - Multichamber pump, valve for such a pump and use of the pump

Info

Publication number: WO1989012166A1
Application number: PCT/CH1989/000099
Authority: WO
Inventors: Erich Kläui
Original assignee: Gebrüder Sulzer Aktiengesellschaft
Priority date: 1988-06-03
Filing date: 1989-05-25
Publication date: 1989-12-14
Also published as: BR8906986A; NO892276L; JPH02504539A; EP0345210A1; NO892276D0

Abstract

A multichamber pump (2) comprises a series of chambers (21, 21') with corrugated walls (22) or nesting walls. The chambers are separated by a valve tray (23) on which is mounted a valve (26) which has a lower resistance to flow in the direction of delivery (arrow) than in the reverse direction. The pump can be driven, i.e. the valve tray (23) can be moved, for example by a linear motor (24, 24', 25) or by a hydraulic motor. The multichamber pump (2) is suitable for delivering multiphase pumping media.

Description

Multi-chamber pump, valve for such a pump and use of the pump.

The invention relates to a multi-chamber pump with at least two chambers. The invention further relates to a valve for such a pump and uses of the pump.

Squeeze pumps are known, for example, in which a flexible hose with squeeze rollers, which are attached to a rotating wheel, is divided into several chambers in the pump section of the hose. The squeeze rollers press the hose against a solid base, for example a plate. Each of the chambers is filled with a conveying medium which is pumped on by the rolling of the squeeze rollers. These pumps often fail when the pumped medium is, for example, a liquid-gas mixture. Larger quantities of gas are only produced with insufficient efficiency. If the pumped medium also contains solids, there is a risk of damage to the flexible hose. The object of the invention is to provide a pump which is capable, for example, of conveying media with any and also changing mixing ratio of liquid and gas phase with sufficient efficiency. The pump should be able to deliver both the pure gas phase and the pure liquid phase. Another object of the invention is to provide a valve which is particularly suitable for such pumps. Another object of the invention is to show particularly advantageous further uses of such pumps according to the invention.

According to the invention, a multi-chamber pump with at least two chambers with variable volume is provided, the chambers being connected in series in the conveying direction of the conveying medium, and each of the chambers having at least one inlet valve and / or at least one outlet valve, one for the flow of the Delivery medium has lower flow resistance than in the opposite direction, and the chambers have means which allow the enlargement and reduction of the chamber volume of at least one of these chambers, and with drive and control means for enlarging and reducing the volume of at least one chamber. According to the invention, the valve is characterized by the features in the characterizing part of independent claim 22. The use of the multi-chamber pump is characterized according to the invention by the features in the characterizing part of independent claims 23 and 24.

The dependent claims relate to advantageous developments of the invention.

A multi-chamber pump according to the invention conveys problem-free single and multi-phase mixtures with any proportions of the individual phases in liquid and gaseous form Funding or funding medium. However, it is also possible to promote only one of the two phases alone with sufficient efficiency. By selecting a valve that causes a considerable mixing of the phases in the mixture as it flows through, the separation of the two phases is prevented. The arrangement of chambers directly adjacent to each other enables compact design, simple drive, possibly only a single valve base, and the double function of individual valves as an outlet valve for one chamber and an inlet valve for the next. The use of flexible chamber walls, for example bellows made of flexible material, such as an elastomer, enables simple constructions. The rather low compressive strength of such bellows alone can be significantly increased with a corset-like pressure jacket or pressure vessel.

A wide variety of systems are suitable for driving the pump, for example hydraulic pistons, in particular hydraulic ring pistons, electric linear motors, e.g. Synchronous or asynchronous motors designed as canned linear motors, forward and reverse spindle drives, rack and pinion drives, drives with clutches for forward and reverse running, etc.

The installation of spring elements as stops for, for example, oscillating telescopic tubes enables not only the gentle braking of these machine parts, but also the recovery of energy for the return in the opposite direction. Building the pump as a mechanical oscillator is particularly interesting and advantageous when operating at the resonance frequency, also in terms of energy consumption. As a spring element to compensate for pressure pulsations in the system, a cavity can be provided as a gas chamber which fills with gas when conveying, for example, a liquid-gas mixture. The cavity can be machined as part of a valve. However, the valve can also take over the function of a displacement body and / or separate displacement bodies can be provided which reduce the dead volume of the pump chambers (dead volume = volume of the delivery medium which remains in the pump chamber at the end of the delivery phase), which reduces the efficiency of the pump improved.

In order to improve the running and the mode of operation of the pump in the case of multi-phase conveying media, it may be advantageous to keep the ratio of, for example, the liquid to gas content within certain limits or not to let the liquid content drop below a predetermined amount, which is the case with recirculation devices can be achieved. In such recirculation devices, the conveying medium (gaseous and / or liquid) is fed via return lines from subsequent, preferably the last stage of a previous, preferably the first stage of the pump, in order to maintain or maintain the desired ratio of the phases. It would also be conceivable to arrange baffle plates or other liquid separators in front of the outlet valve in centrifugal separators in order to obtain this desired ratio of the phases.

The multi-chamber pump can be constructed from a series of identical stages connected in series, it being readily possible to generate a pressure increase of about 10 bar per stage, ie per chamber, and of about 30 bar or more in the case of telescopic tube constructions of the chambers . With such pumps pressure increases of 50 to 100 bar can be easily achieved.

The movement of the individual chambers or chamber floors is controlled in such a way that the most continuous possible conveyance is achieved. The number of stages N should generally be equal to 360 ° divided by the phase difference in degrees or a multiple thereof. For example, three stages connected in series, which run 120 ° out of phase with a time-symmetrical filling and delivery phase, already show excellent pump properties.

In push-pull operation (180 ° phase difference) e.g. the movements of the individual chambers or valve bases are controlled in such a way that one chamber is always alternately in the conveying phase and the neighboring chambers are in the filling phase.

The filling and conveying phase do not need to have the same duration. Rather, it may be advantageous to design the delivery or compression phase longer than the return or filling phase. The valve bottoms can be driven according to a trapezoidal course of movement, sinusoidally or otherwise according to a movement curve.

The interplay of the movement sequences of the stages can be achieved in different ways. It is particularly important that the subsequent stages are controlled and constructed in such a way that the adaptation to the physical conditions of the continuity equation (law of the constancy of the mass flow for a flow, ie the difference of the overflowing through a control surface in a period of time) the inflowing mass must equal that within this period disappeared from the control surface) continuously and without unnecessary energy expenditure. For example, in pure liquid operation, it is advantageous if the movement takes place according to a rigid cycle common to all stages. The synchronism becomes less important the larger the compressible part in the medium is in a multi-phase mixture. Systems of this type can be built in such a way that they adapt themselves to the funding optimum with a certain composition of the medium (self-adaptation). This self-adaptation can be achieved, for example, by driving each pump stage with a given output or by designing it for a certain maximum delivery pressure (pressure increase between the inlet and outlet of the stage). This avoids overloading individual stages and distributes the drive power evenly across the stages.

The performance of the drive of the individual stages of the pump can be adapted differently. Electric motors can be provided with a current and thus pressure and / or power limiter. Hydraulic motors e.g. can be supplied from a source with constant pressure, so that the pump stages adjust to constant delivery pressure.

Tower or storey valves are particularly advantageous for pumps according to the invention due to their large possible flow rate in the flow direction with a small flow resistance and excellent blocking resistance in the opposite direction, with a simple design and high reliability.

Because of the excellent intermixing of the conveying means during the pumping process, such a pump is also suitable as a direct current mass exchanger, direct current mixer and / or gassing device. The expression Direct current is to be interpreted as co-current (in contrast to a counter-current mixer). A pump according to the invention, which is used only as a mixer, can only have a slightly higher outlet pressure than the inlet pressure.

Another way to achieve self-adaptation is to let some of the valve bottoms run free, no longer in sync, i.e. the movements of the valve bottoms are no longer controlled by a common, predetermined cycle, but the valve bottoms themselves reverse their direction of movement at the end of their stroke by means of limit switches. In the case of pure liquid delivery, the stages still run synchronously due to the incompressibility of the liquid column. However, as the compressible proportion in the feed mixture increases, the synchronism is released, so that the stages can adapt in a practically ideal way to the requirements of the continuity equation, among other things. depending on the composition of the multi-phase feed mixture.

In the case of the hydraulically driven pump, the individual stages can themselves be designed as differential cylinders, so that no separate drive cylinders are necessary.

For this purpose, each stage can be enclosed in a pressure vessel. The diameter of the bellows or of the telescopically interlocking tubular sleeves is smaller on the entrance side of the step than on the exit side.

Increasing or lowering the pressure in the pressure vessel results from the difference in diameter (Cross-sectional difference) in the movable part of the step an axial force that drives this movable part.

The advantage of such arrangements, in particular in the case of telescopic variants, is that the pressure in the pressure vessel can be kept higher than in the pumped medium itself. This prevents leakages to the outside. Internal leaks are hardly a problem if the pressure or drive fluid consists of the pumped medium itself or is selected so that it is compatible with it.

Bellows made of highly flexible material, such as Elastomers have the advantage that large percentage changes in length, for example 100%, are permissible. This allows the dead volume to be kept within limits. This also enables large-stroke, slow-running pumps of relatively short overall length to be realized. The disadvantage of such flexible bellows is their low pressure resistance of, for example, only about 5 bar, which can lead to large numbers of stages in the case of larger pressures to be achieved.

In contrast, metal bellows are much more pressure-resistant and, for example, still suitable for pressures of 20 bar. However, they allow changes in length in continuous operation, i.e. Pump movements, for example, only 10% too. With a conventional arrangement of the valve heads (valve head in the middle of the bellows), this leads to very high dead volumes. This disadvantage can be partially remedied by the asymmetrical arrangement of the valve levels (valve level at the end of the bellows).

Pump chambers in which the valve heads are driven directly, ie by means of a rigid mechanical connection, have the disadvantage that the linear motors are only fully utilized during the delivery stroke. Further the direct drive of the valve bottoms requires relatively large forces and low speeds.

Both lead to the fact that the linear motors become large and heavy, have a poor efficiency and are poorly used. Linear motors achieve better efficiency and can be built lighter and more compact if they are designed for lower forces and higher speeds and are fully loaded in both directions of movement. This is possible if the oscillating movement of the linear motor is transmitted to the valve bottoms by means of a suitable transmission. This transmission must be such that it converts the faster but less powerful movement provided by the linear motor into the slower but more powerful movement required for the valve bottoms and the forward and backward movement of the linear motor is used for conveying.

Such transmission can be mechanical, e.g. by means of cable or steel belt hoists, racks etc. or also hydraulically.

The invention is explained in more detail below with reference to the drawings, which show exemplary embodiments of the invention and details.

Show it:

Fig. 1 The basic scheme of an inventive

Pump with four driven valve heads with one valve each;

Fig. 2 schematically, in section, a pump with flexible bellows as chamber wall and with electrical linear motor as drive for a single valve base and with a tower valve in this valve base;

Fig. 3 schematically, in section, a pump with tubes that are telescopically moved into each other and with hydraulic cylinder drive for the valve bottom with a cone valve;

4 schematically, in section, a pump with tubes that are telescopically moved into one another and with a hydraulic ring piston drive for the valve base with a tilting disk valve;

Fig. 5 schematically, in section, a pump with tubes that are telescopically moved into each other and with an electric linear motor drive for the valve bottom with a lamella valve;

Fig. 6 schematically, in section, a tower or floor valve;

Fig. 7 schematically, in section, parts of a

Pump stage with a differential cylinder with hydraulic drive;

Fig. 8 schematically, in section, parts of a

Chamber pump with highly flexible bellows and pressure-resistant, less flexible metal bellows;

Fig. 9 schematically, in a section, a

Multi-chamber pump with linear motor and hydraulic reduction drive or transmission;

Fig. 10 in a schematic section two possible Types of magnetic drives for pump stages;

1 shows the pump 1 with the chambers 10, 11, 12 and 13 and the axially driven valve bottoms with the valves 14, 15, 16 and 17, in the flow direction / delivery direction (generally indicated by arrows) and against them Direction can be moved back and forth. The flow resistance of the valves 14, 15, 16, 17 is direction-dependent and significantly lower in the flow direction. A power supply 18 supplies the controls 19, 19 ', 19 "19" ^• and motors M, M', M ", M""with, for example, electrical or hydraulic energy. The walls of the chambers 10, 11, 12, 13 are here It is possible to ensure that a certain proportion of a phase of a multi-phase mixture is always present in the pump with the recirculation device R. The amplitude of the movements of the valve bottoms 14, 15, 16, 17 is determined, for example, by the limit switches or reversing switches E, E 'are limited and controlled.

The walls 21 and 22 of the chambers 21 'and 22' of the pump 2 of FIG. 2 are made of a flexible material, for example a reinforced elastomer. The tower valve 26 is mounted in the valve base 23, which is moved axially back and forth by the motor with the stator 24 and the stator winding 24 ′ and the armature 25. The pump 2 is encapsulated in a pressure vessel 27 and the space 28, 28 'surrounding the chambers 21' and 22 'is filled with a liquid which is under pressure. The hydrostatic pressure on the walls 21 and 22 of the chambers 21 ', 22' is thus equalized, which relieves the walls 21, 22. The cavity 26 'in the valve 26 fills with gas when the valve is in a vertical position and serves as a gas cushion or gas spring. The resilient stops 29, 29 ', 29 ", 29'" serve, inter alia, for Recovery of the kinetic energy of the moving parts of the pump.

In the pump 3 of FIG. 3, the pipe 31 moves in the fixed pipe 32. The seal 33 seals the gap between the two pipes 31, 32. The pipe 31 is connected to the valve base 34, which has a cone valve 35. The valve base 34 is driven by the hydraulic cylinders 37. The gas cushion or gas spring is formed in the cavity 38 here. The two displacement bodies 39 serve to reduce the dead space of the pump chambers.

In the pump 4 of FIG. 4 too, the walls of the pump chambers are formed by pipe parts, the standing pipe 41 and the moving pipe 42. The moving tube 42 is driven hydraulically, in that the tube 42 is designed as an annular piston which is alternately pressurized in the annular chambers 40, 40 ^r . A tilting disk valve 44 is provided here as the valve in the valve base 43.

The pump 5 of FIG. 5, which is only drawn on one side, again has a telescopic tube-like structure with the movable tube jacket 51 and the stationary tube jackets 52, 53. The lamella valve 55 is located on the valve base 54. As a seal between the tube jackets 51 and 52 or 51 and 53 serve the flexible roll membranes 56, 56 '. The pump is driven by the linear motor 57, which essentially comprises the stator 57 ', the winding 57''and the armature 57 "'. The permanent magnet 58 serves to polarize the motor. The cavities 50, 50 'are filled with liquid in order to stabilize and support the rolling diaphragms 56 and 56. The springs 59, 59 'together with the valve 55, the valve base 54, the tubular jacket 51 and the armature 57'"form the linear motor 57 and the permanent magnet 58 a mechanical oscillator, which is preferably operated at the resonance frequency.

2 to 5 show only individual stages and chambers of multi-chamber pumps according to the invention. A pump can of course consist of several such stages. It is also possible to have such pumps work in parallel according to the invention, or to arrange them in parallel. Each chamber has at least one inlet valve and one outlet valve.

Finally, FIG. 6 shows in two half-sided sections a tower or floor valve 6, on the left as an inlet valve and on the right as an outlet valve. The channels 60 in the jacket 61 of the valve 6 have a significantly lower flow resistance in the flow or conveying direction (arrows) than in the opposite direction.

However, other, preferably preloaded valve constructions, such as ball, cone, tilting disk, lamellar valves, etc. are also suitable for a pump according to the present invention.

The pump stage of FIG. 7 shows a pump stage with a differential cylinder as a telescopic variant. The pressure vessel 73 encloses the step. The outlet-side pipe jackets 74, 75 have a larger diameter than the inlet-side pipe jackets 76, 77. The liquid-filled pressure chamber 78 is connected via the pressure connection 79 to the hydraulic system for driving the pump. The spring 70 returns the valve base 71 to the starting position after each delivery stroke if the pressure of the delivery medium in the actual pump chamber itself is insufficient. FIG. 8 shows a pump concept with two stages connected in series, in which the advantages of the great flexibility of bellows or membranes made of highly flexible material are combined with the pressure resistance of metal bellows and large pressures are achieved with a few stages and a correspondingly small overall length.

The valve bottoms 85, 86 are arranged at the lower and upper ends of the metal bellows 87, 88. This means that even with the small strokes caused by the metal bellows, there are no large dead volumes. Large pressure differences can be achieved in gas operation, which makes it possible to keep the number of stages low. The steps are enclosed by the liquid-filled pressure container 89, 89 '. The bellows 81 made of flexible material is located between the valve bottoms. Due to the flexibility of this bellows, the pressure in the pressure vessel is always the same as that between the valve bottoms. As a result, the flexible bellows is not deformed under pressure and the metal bellows are only subjected to the pressure of a single step. As a result of the same internal and external pressure ratios, highly flexible bellows can be used and, at the same time, favorable overall lengths can be achieved. The length of a step is reduced by almost half compared to a step in which the highly flexible bellows 81 would be replaced by one or more metal bellows. The drive of the valve bottoms 85, 86 is not shown here and can take place in any form. Finally, the bellows 81 could also be omitted. However, this would make the dead volume approximately larger.

9 shows an example of a multi-chamber pump with hydraulic transmission, reducing the fast drive movement of a linear motor to slower drive movements of a hydraulic drive. The pump consists of the chambers 92 with the valve bottoms 93. This are driven by the cylinders 94. The pump is surrounded by the tubular linear motor 95, the armature 95 'of which acts on the cylinder 96. The cylinders 94 of successive valve bottoms are alternately connected to the upper and lower pressure chambers of the cylinders 96, respectively. By appropriate selection of the piston surfaces of the cylinder 94 and. 96 can be any transformation ratio of the forces or the speeds are achieved and set.

The example shows a pump train with four valve bottoms. However, the principle described can be applied to any number of chambers, and in extreme cases only a single linear motor is required for the entire pump train. Instead of the tubular linear motors enveloping the pump line, motor units arranged next to the pump line could of course also be provided separately.

The reciprocating movement of the valve bottoms can also be done without a direct mechanical connection between the valve bottom and drive means, e.g. by means of magnetic fields, generated resp. be forced on them.

The essential elements of the pump stage with magnetic drive from FIG. 10 consist of the primary part 107, 108, the can 109 made of non-magnetic material which also forms the chamber wall, the secondary part 110 with valve base 111 and the valve 112. Secondary part 110 and valve base 111 form a piston with the seal 113, which can move axially freely in the can 109.

The primary part 107, 108 generates a magnetic field, which acts on the secondary part 110 through the can 109 and drives it in the axial direction. The primary part can either come from the stator consist of a linear motor with winding or it can consist of an arrangement of magnetic poles which are mechanically moved back and forth. The secondary part is analogous to the armature of a linear motor, and is designed to match the primary part, for example as a DC, synchronous, reluctance or induction machine armature.

In FIG. 10, two possible exemplary embodiments for the pump stage are shown on each side. The left half shows a stator 107 'with its winding 107' 'as the primary part. The right half shows an arrangement of magnetic poles as the primary part, which are moved up and down with the aid of the hydraulic cylinder 104. The arrangement of magnetic poles consists of the ring-shaped pole shoes 108 'made of soft iron and the permanent magnets 108 "located in between and also arranged in a ring. The magnets are polarized so that the magnetic flux essentially follows the direction 108'" shown. The secondary part 110 is constructed in the same way as the primary part 108 and in principle also fits the stator 107 shown on the left. However, the pump train can also be divided into several sections and a separate linear motor can be assigned to each section.

Claims

1. Multi-chamber pump (1), with at least two chambers (10, 11, 12, 13) with variable volume, the chambers (10, 11, 12, 13) being connected in series in the conveying direction (arrow) of the conveying medium, and each of the chambers (10, 11, 12, 13) has at least one inlet valve (14) and / or at least one outlet valve (15) which has a lower flow resistance in the conveying direction for the flow of the conveyed medium than in the opposite direction , and the chambers (10, 11, 12, 13) have means which make it possible to enlarge and reduce the chamber volume of at least one of these chambers, and with drive (M, M ', M ", M"') and control units ¬ means (19, 19 ', 19 ", 19'") for enlarging and reducing the volume of at least one chamber (10, 11, 12, 13).

2. Multi-chamber pump according to claim 1, characterized gekennzeich¬ net that each chamber (10) has a valve plate with at least one inlet valve (14 or 15) and / or a valve plate with at least one outlet valve (15 or 16) that at least one the valve bottoms can be moved to and from the others in such a way that the volume of the chambers (10, 11) is controllably larger and smaller.

3. Multi-chamber pump according to claim 1 or 2, characterized in that adjacent chambers (10, 11) have a valve base with at least one valve (15) in common, which is for the upstream chamber

(10) Exhaust valve and for the downstream chamber

(11) Intake valve is.

4. Multi-chamber pump according to one of claims 1 to 3, characterized in that the chambers (10, 11) are designed like hollow cylinders and their jacket wall consists of bellows-like flexible material.

5. Multi-chamber pump according to claim 4, characterized gekennzeich¬ net that at least one of the chambers (21 ', 22') is encapsulated in a pressure vessel (27).

6. Multi-chamber pump according to one of claims 1 to 3, characterized in that the chambers are rigid and tube-like and the tube jackets (31, 32) interlock telescopically.

7. Multi-chamber pump according to one of claims 1 to 6, characterized in that the drive means comprise at least one linear motor (24, 24 ', 25).

8. Multi-chamber pump according to one of claims 1 to 7, characterized in that the drive means comprise at least one hydraulic piston motor (37).

9. Multi-chamber pump according to claim 8, characterized in that the at least one hydraulic piston motor is designed as an annular piston motor (40, 40 ', 42).

10. Multi-chamber pump according to one of claims 1 to 9, characterized in that dasε εie resilient stop elements (29, 29 ', 29 ", 29'"), against which parts of the chambers (25) moving against and / or from each other run up .

11. Multi-chamber pump according to one of claims 1 to 9, characterized in that the drive means as mechanical oscillator with spring elements (59, 59 ') are formed.

12. Multi-chamber pump according to claim 11, characterized gekenn¬ characterized in that it has a single-phase AC motor (57 ", 57 '", 58) for exciting the mechanical oscillator.

13. Multi-chamber pump according to one of claims 1 to 12, characterized in that at least one chamber (21 '), preferably in a valve (26), has a cavity (26') which can be at least partially filled with gas.

14. Multi-chamber pump according to one of claims 1 to 13, characterized in that it has a recirculation device (R) for at least one phase of a multi-phase delivery medium.

15. Multi-chamber pump according to one of claims 1 to 14, characterized in that the drive means are arranged in a jacket-like manner around the chambers.

16. Multi-chamber pump according to one of claims 1 to 15, characterized in that the chamber walls of adjacent chambers have bellows made of differently flexible materials.

17. Multi-chamber pump according to one of claims 1 to 16, characterized in that these chambers have different cross sections.

18. Multi-chamber pump according to one of claims 1 to 17, characterized in that the drive of Ventil¬ floors takes place magnetically.

19. Multi-chamber pump according to one of claims 1 to 18, characterized in that at least one pressure chamber has displacement bodies for reducing the dead volume.

20. Multi-chamber pump according to one of claims 1 to 19, designed as a self-adaptive system, in which each pump stage is driven with a predetermined maximum output or its drive is designed for a predetermined, maximum delivery pressure.

21. Multi-chamber pump according to one of claims 1 to 20, designed as a self-adaptive system, in which at least the valve bottom of a stage εich reverses εelbεt at the stroke end.

22. Valve for a multi-chamber pump according to one of claims 1 to 21, which is designed as a tower or floor valve (6).

23. Use of a multi-chamber pump according to one of claims 1 to 21, as a pump for conveying a multi-phase delivery medium, in particular for liquid-gas mixtures or liquid-gas-solid matter.

24. Use of a multi-chamber pump according to one of claims 1 to 21 as a direct-current mass transfer machine, a direct-current reactor, a direct-current mixer and / or as a gassing device for the conveying media.