DE102012013681A1 - Pump module, as well as positive displacement pump - Google Patents

Abstract

The invention relates to a pump module (4, 5, 6; 4 '; 4' ') with a housing (14) delimiting at least one flow channel (17), the at least one flow channel (17) having at least one inlet (7, 8, 9) connects to at least one outlet (10, 11, 12) and accommodates in each case a pump device that is oriented in the flow direction and that can be deflected in sections via individually controllable actuators. A medium to be pumped can be enclosed within at least one pumping chamber (20, 21), which can be encapsulated by sequential activation of the actuators between sections of the pumping device and each associated peripheral section of the at least one flow channel (17) and in the course of a pumping movement between the at least one inlet ( 7, 8, 9) and the at least one outlet (10, 11, 12) is movable. In order to provide a precisely conveying pump module with a simple structure at the same time, the actuators are accommodated by the housing (14), actuators (A1 to A6) which are located opposite one another on both sides of the flow channel and which are arranged in succession in the flow direction. Furthermore, the pump device is designed as an elastic membrane (18; 21; 22), which can be applied to an associated circumferential section of the at least one flow channel (17) by actuating one actuator each of the individual actuator stages (A1 to A6) ,

Description

Field of the invention

The invention relates to a pump module having a, at least one flow channel limiting housing, wherein the at least one flow channel connects at least one inlet with at least one outlet and each one oriented in the flow direction pumping device receives, which is deflected by individually controllable actuators sections, and wherein a conveying medium can be enclosed within at least one delivery chamber, which can be encapsulated by sequential activation of the actuators between sections of the pumping device and respective associated peripheral sections of the at least one flow channel and is movable between the at least one inlet and the at least one outlet in the course of a delivery movement. The invention further relates to a positive displacement pump for delivering a fluid, in which at least one aforementioned pump module is used.

In positive displacement pumps, a medium which has flowed into an interior of the pump via an inlet is usually encapsulated in a delivery chamber and subsequently displaced into an outlet. In order to prevent backflow of the medium into the inlet during this displacement and to prevent a sucking back of already displaced medium, an inlet and outlet control via pressure-controlled valves or other design measures is usually provided. As a result, however, the required number of components is increased and also makes it difficult to achieve a low final pressure, since the valves are usually differential pressure controlled and result in low pressures no sufficiently high contact forces in the valves. Depending on the manner in which the respective conveying movement is initiated, friction losses and vibrations also occur. Incidentally, positive displacement pumps are partially designed with pump modules in which the number of components is reduced and a conveying movement is as easy as possible to represent.

State of the art

From the JP 03 081585 A goes out a pump module, which has a cuboid flow channel limiting housing. The flow channel connects an inlet with an outlet and accommodates a pumping device. This pumping device is oriented in the flow direction and formed by a plurality of Piezoaktorenabschnitte which lined up a kind, lying within the flow channel lamella arise. By driving the individual Piezoaktorenabschnitte this blade can be deflected in sections, in which case it comes to rest with the respective sections of the surrounding housing and includes a medium to be conveyed within a respective delivery space formed thereby. If the piezoelectric actuators are now controlled sequentially, the medium enclosed in the respective delivery chamber is moved from the inlet to the outlet in the course of a peristaltic delivery movement.

Starting from the above-described prior art, it is an object of the present invention to provide a pump module in which a conveying movement can be introduced in a precise manner with a simultaneously simple construction.

Disclosure of the invention

This object is achieved on the basis of the preamble of claim 1 in conjunction with its characterizing features. The following dependent claims give each advantageous embodiments of the invention. A positive displacement pump, in which at least one pump module according to the invention is used, is evident from the further claims 8 to 10.

According to the invention, a pump module has a housing delimiting at least one flow channel, wherein the at least one flow channel connects at least one inlet to at least one outlet and accommodates a respective pump device oriented in the flow direction. This pumping device can be deflected in sections via individually activatable actuators, wherein a medium to be conveyed can be enclosed within at least one delivery chamber, which can be encapsulated by sequential activation of the actuators between sections of the pumping device and associated peripheral sections of the at least one flow channel and in the course of a conveying movement between the at least one inlet and the at least one outlet can be moved.

The pumping device is designed according to the invention in particular as a disk-shaped, plate-shaped or similarly constructed component and can be deflected in sections by individual segments are moved under the influence of the actuators orthogonal to the longitudinal extent of the pumping device. Here, depending on the number of deflected portions of the pumping device, one or more delivery chambers are enclosed with one or more peripheral sections of the flow channel, wherein in each case a medium to be delivered is enclosed in a delivery chamber. For the purposes of the invention, this medium is in particular, a fluid, ie a gas or gas mixture or a liquid or a liquid mixture. By means of a sequential actuation of the actuators, the thus limited, at least one delivery space is then moved between the at least one inlet and the at least one outlet of the pump module, so that the enclosed medium to be conveyed is also conveyed between inlet and outlet. This conveying movement is similar in this case with appropriate control of the actuators in particular a peristaltic movement of the pumping device.

The invention now encompasses the technical teaching that the actuators are accommodated by the housing and in each case form actuator stages on both sides of the flow channel that are opposite one another and are arranged successively in the flow direction. Furthermore, the pump device is designed as an elastic membrane, which is applied by driving one actuator each of the individual actuator stages, each with an associated portion to each an associated peripheral portion of the flow channel. In other words, therefore, the actuators, via which the pumping device located in the flow channel can be deflected in sections, placed in the surrounding housing, the actuators are hereby combined in pairs to actor stages, in which each of the respective actuators are located on both sides of the flow channel, so the an actuator of an actuator stage above the flow channel and the other actuator of this actuator stage are positioned below the flow channel. Overall, the actuator stages are arranged successively in the flow direction, so that in a flow along in the flow direction so the individual actuator stages are passed successively. The configured as an elastic membrane pump device can then be partially deflected by each driven an actuator of the individual actuator stages and this one, lying between the actuators of this actuator stage section of the membrane and applied to the local peripheral portion of the flow channel.

An inventive pump module is characterized by a simple structure with simultaneous reliable operation. Because by placement of the actuators in the housing itself at rest, these can be controlled in a simple manner via running in the housing lines, these lines are spatially separated from the flow channel and the medium conveyed herein. Furthermore, due to the nature of the conveying movement, it is possible to dispense with inlet-side and outlet-side valves, since the medium to be delivered is encapsulated by the section-wise deflection of the elastic membrane between the same and the circumference of the flow channel. The membrane is the only moving component, so that a long life of the pump module according to the invention can be achieved by appropriate optimization. In addition, the membrane can be precisely deflected as an elastic component and applied to the circumference of the flow channel, whereby the respective delivery chamber can be precisely defined and sealed. Furthermore, a pumping frequency of the pump module, as well as a pumping sequence, i. H. the definition of a size of the at least one delivery chamber, are set freely via the actuators, so that the pump module according to the invention is universally suitable for different applications, then depending on the type of desired promotion only a control of the actuators is to be varied. Overall, the pump module according to the invention is characterized by a simple structure with low manufacturing complexity and low noise.

In contrast, in the pump module of JP 03 081585 A a control of the, lying in the flow channel pumping device difficult because the sectionwise deflection provided on the lamellar component piezoelectric sections must be energized accordingly. For this purpose, appropriate contacts must be provided or lines are brought to the deflectable pumping device, which complicates the construction of the pump module accordingly and consequently increases the manufacturing effort. Furthermore, the lamella provided with piezo elements is less flexible than a membrane, especially as a definition of delivery chambers is fixed in accordance with an arrangement and size of the piezoelectric sections. Accordingly, a pumping sequence can not be tailored individually to individual applications. Even a snuggling of the lamella on the circumference of the flow channel is less accurate than an elastic membrane.

According to an advantageous embodiment of the invention, the actuators are formed by magnetic coils. These are in particular in each case surrounded by a material of high permeability, such as iron, and generate when energized a corresponding magnetic field, via which the elastic membrane is deflected with their respective associated sections. In order to achieve the partial deflection of the membrane in the magnetic field, the membrane according to an embodiment of the invention consists either of a magnetorheological elastomer material or is formed of an elastomeric material, in which in each of the actuator stages associated portions of the membrane a ferromagnetic material is introduced. A magnetorheological elastomer is a composite material a soft elastomer matrix with magnetically polarizable particles provided therein, which can be acted upon by the magnetic field. In the case of the design of the membrane made of an elastomeric material with ferromagnetic material incorporated therein, in particular sheet metal segments are encapsulated with elastomeric material in the meaning of the invention, so that a composite system is configured.

According to an alternative embodiment of the invention, the actuators are formed by electrodes. With appropriate energization of these electrodes each case an electric field is generated, via which the elastic membrane in turn can be deflected in sections. For this purpose, the elastic membrane then consists in particular of an electrorheological elastomer material which is formed from an elastomer with particles introduced therein, which are pulled in the electric field in the direction of the respective energized electrode and accordingly cause a partial deflection of the elastic membrane.

According to a further embodiment of the invention, the housing consists of at least two housing parts, wherein the housing parts and the intermediate membrane are designed as circular discs. Furthermore, the at least one inlet is provided radially on the outside and communicates via the flow channel with the at least one outlet, which is placed centrically in the radial direction. In this case, the pump module thus has a circular structure, wherein the medium to be conveyed is conveyed from radially outside to radially inside to the outlet. For the purposes of the invention, however, the inlet can also be placed centrically just as well, and the at least one outlet can be located radially on the outside. Due to the circular structure of the pump module several pump modules can be connected in series without problems by the individual circular pump modules are stacked axially and depending on the desired circuit shown a parallel supply of individual feeds or after at least one outlet of a module with the at least one inlet of the subsequent module after Type of series connection is coupled. In a circular structure of the pump module of circular discs then the actuators are to make corresponding annular, so for example as annular coils or annular electrodes. As an alternative to the circular structure, however, a rectangular structure of a pump module is also conceivable in principle.

In a further development of the invention, the actuator stages are placed equidistantly or at different distances from each other in the flow direction. Depending on the shape of the pump module and the type of medium to be conveyed, the at least one delivery chamber can be kept constant in its volume or changed during its movement between the at least one inlet and the at least one outlet. Thus, a medium in the form of a gas or a gas mixture can be compressed when being conveyed from the at least one inlet to the at least one outlet by the distances between the actuator stages are selected equidistantly in the flow direction in an annular structure of the pump module, so that the at least one pumping chamber at Movement of a radially outer inlet to the centric outlet steadily reduced due to the decreasing annular surfaces between the actuator stages and thus a compression of the gas is made. Similarly, in the case of a rectangular structure, a constant reduction of the at least one delivery chamber can be defined by different distances between the actuator stages.

On the other hand, if the medium to be delivered is a liquid, a reduction in a volume of the at least one delivery chamber is usually undesirable because of the incompressible behavior of the liquid. When moving between the at least one inlet and the at least one outlet, this volume can be kept constant either by placing the individual actuator stages in a circular pump module with uniform spacing in the direction of flow relative to one another or by maintaining uniform spacings in a rectangular structure of the pump module are selected between the actuator stages. Finally, a delivery of a liquid in a circular structure of the pump module and equidistantly placed actuator stages is possible if the at least one inlet is centric in the flow direction and the at least one outlet is provided radially outwardly so that a volume of the at least one delivery chamber when moving between Inlet and outlet enlarged.

However, variable or constant volumes of a delivery chamber can also be defined by a corresponding setting of the pumping sequence. Since an encapsulation and a movement of the respective delivery chamber is controlled by controlling the corresponding actuator stages, by varying the actuation of the actuator stages, a size and change of the delivery chamber can be set almost freely. Thus, a compression of the medium, which otherwise takes place due to the distance of the actuator stages to each other and the structure of the pump module during movement of the pumping chamber, thereby either increased or decreased, so that the exhaust side each desired pressure level of the medium can be achieved.

According to the invention, at least one pump module designed according to one of the aforementioned variants forms a positive displacement pump via which a fluid can be conveyed and which is in particular a pre-pump of a turbopump. Preferably, however, a plurality of pump modules are arranged in a series and / or parallel connection in a pump housing, so that pumping via the individual pump modules in parallel or sequentially to one another into a common outlet.

According to a further advantageous embodiment of the invention, the actuators of the at least one pump module are controllable via power electronics. About such a power electronics different pumping frequencies and pumping sequences can be represented by appropriate control of the actuators easily, in which case a coordinated control of several pump modules can be done. Apart from a power electronics associated with the one or more pump modules, this may also be a corresponding electronics of another pump, such as a turbomolecular pump, or another system.

The invention is not limited to the specified combination of the independent claims or the dependent claims. It also results in ways to combine individual features, even if they emerge from the claims, the following description of embodiments of the invention or from the figures. The reference of the claims to the drawings by use of reference numerals is not intended to limit the scope of the claims

Preferred embodiments of the invention are explained below with reference to the accompanying drawings. These show:

1 a schematic representation of a positive displacement pump according to a first preferred embodiment of the invention;

2 a schematic representation of a pump module of the positive displacement pump 1 , according to a first embodiment possibility;

3 a representation of individual switching sequences of the pump module 2 ;

4 a schematic representation of a pump module of the positive displacement pump 1 , according to an alternative embodiment possibility;

5 a schematic representation of a pump module of the positive displacement pump 1 , according to another alternative embodiment of the invention; and

6 a schematic representation of a positive displacement pump according to a second embodiment of the invention.

Detailed description of the drawings

Out 1 is a schematic view of a positive displacement pump according to a first embodiment of the invention, which is in this positive displacement pump is in particular a backing pump of a turbomolecular pump. The positive displacement pump has a pump housing 1 in which between one side of the pump housing 1 provided inlet side 2 and a front outlet side 3 several equally constructed pump modules 4 . 5 and 6 are provided. The pump modules 4 to 6 are each designed as circular, rotationally symmetric modules, which each have a ring-like inlet 7 respectively. 8th respectively. 9 each with the inlet side 2 in connection and via one, centrally located outlet 10 respectively. 11 respectively. 12 together to the outlet side 3 promote. The pump modules 4 to 6 are therefore in a sequence in a parallel circuit in the pump housing 1 recorded and promote a fluid, in particular in the form of an air mixture, from the inlet side 2 to the outlet side 3 , Furthermore, in the pump housing 1 another power electronics 13 taken over which the individual pump modules 4 . 5 and 6 can be controlled.

Out 2 Next, a schematic single view of the pump module continues 4 which, however, in structure, the pump modules 5 and 6 equivalent. As can be seen, the pump module has 4 over a housing 14 , which consists of two housing parts 15 and 16 composed, which are each designed as discs with a circular cross-section and an intermediate flow channel 17 limit, by the housing parts are arranged at a distance from each other. The flow channel 17 connects the annular inlet 7 , which is only hinted at here, with the centric outlet 10 , where in 2 for reasons of clarity in the radial direction, only one half of the pump module 4 is shown. About the flow channel 17 So can fluid, starting from the inlet 7 , the case 14 flow radially through the outlet 10 axially to the common, in 1 to see outlet side 3 reach.

From the flow channel 17 is also a membrane 18 recorded in the, in 2 shown rest position centered between the two housing parts 15 and 16 located. For this purpose, the membrane 18 for example, in the region of the annular inlet 7 in a suitable manner between the housing parts 15 and 16 clamped. The present is the membrane 18 It is also designed as a disk with a circular cross-section and consists of an elastomeric material, in which several, concentrically around the outlet 10 lying sheet metal rings B1 to B6 are integrated.

As further out 2 it can be seen, a plurality of actuator stages A1 to A6 are further provided in the radial direction respectively at the level of the individual sheet metal rings B1 to B6, which in the flow direction from the inlet 7 to the outlet 10 are arranged consecutively. Each of the actuator stages A1 to A6 is composed of two actuators, which are on both sides of the flow channel 17 and each one of the sheet metal rings B1 to B6 are arranged on both sides. The actuators of the Aktorstufen A1 to A6 are formed by opposing magnetic coils M1.1 to M6.2, which are each surrounded by iron and, combined in pairs, the actuator stages A1 to A6 result. Of each of the actuator stages A1 to A6 is about the power electronics 13 one of the paired magnetic coils M1.1 or M1.2 or M2.1 or M2.2 or M3.1 or M3.2 or M4.1 or M4.2 or M5.1 or M5.2 resp M6.1 or M6.2 energized, so that generated by the respective magnetic coil, a magnetic field and the respective intermediate sheet metal ring B1 or B2 or B3 or B4 or B5 or B6 pulled to the respective coil and thus the membrane 18 is deflected in sections. In doing so, the membrane settles 18 with the respective section to the respective housing part 15 respectively. 16 and thus to a peripheral portion of the flow channel 17 , wherein by appropriate control of the individual coils M1.1 to M6.2 between membrane 18 and the housing parts 15 and 16 Pumping rooms are definable.

In 3 is a complete, exemplary switching sequence for the pump module 4 out 2 shown. As can be seen here, in five individual sequences I to V, a conveying movement from the inlet 7 to the outlet 10 are represented, wherein the single sequence V then in turn corresponds to the single sequence I. In each case one of the coils M1.1 to M6.2 is driven by the individual actuator stages A1 to A6, so that the intermediate membrane 18 with each associated sections each in the direction of one of the housing parts 15 or 16 is deflected and finally rests on this. About the total of six actuator stages A1 to A6 can be on the one hand between the membrane 18 and the housing part 15 delivery spaces 19 and 19 ' and on the other hand between the membrane 18 and the housing part 16 delivery spaces 20 and 20 ' define which in each case in the course of the pumping sequence from the inlet 7 to the outlet 10 to be moved.

This conveying movement, which resembles a peristaltic movement, is now exemplary with reference to the delivery room 19 on the respective single sequences I to V under the synopsis of 2 and 3 First, in the first single sequence I, the delivery room 19 is encapsulated by energizing the magnetic coils M1.1, M2.2, M3.2 and M4.1 and a corresponding amount of fluid between membrane 18 and housing part 15 locked in. The pump room 19 will then continue in the single sequence II in the direction of outlet 10 moved by the solenoid coil M2.1 and Aktorstufe A4 instead of the solenoid M4.1 the solenoid M4.2, and at the actuator stage A5, the magnetic coil M5.1 is energized at the actuator stage A2 instead of the solenoid M2.2. For the transition to the further single sequence III, the magnetic coil M3.1 and the actuator stage A5 instead of the magnetic coil M5.1 then the magnetic coil M5.2 is driven in comparison to the single sequence II in the actuator stage A3 instead of the solenoid M3.2. In addition, the solenoid coil M6.1 is to be energized in the actuator stage A6. Finally, in the single sequence IV that in the pump room 19 located fluid in the outlet 10 promoted by the solenoid Mule M4.1 instead of the solenoid M4.2 and the actuator A6 instead of the solenoid M6.1, the solenoid M6.2 is operated compared to the single sequence III in the actuator stage A4. In the single sequence V, a new cycle begins with encapsulation of the delivery chamber 19 ' ,

Out 2 is here seen that the actuator stages A1 to A6 are placed equidistantly from each other. In combination with the circular structure of the housing parts 15 and 16 and also the membrane 18 reduce the pumping rooms 19 . 19 ' . 20 and 20 ' in the radial conveying movement continuously in its volume, since the ring volumes defined between the actuator stages A1 to A6 to the outlet 10 become continuously smaller. This has the consequence that in the respective delivery room 19 respectively. 19 ' respectively. 20 respectively. 20 ' located fluid when pumped from the inlet 7 to the outlet 10 is compressed.

About the power electronics 13 must be within each of the actuator stages A1 to A6 and also between the actuator stages A1 to A6 quick change executable to pressure fluctuations in the delivery chambers 19 . 19 ' . 20 and 20 when moving to the outlet 10 keep as low as possible.

Out 4 goes an alternative embodiment possibility of a pumping module 4 ' which instead of the pump modules 4 to 6 at the positive displacement pump in 1 Application can be found. Unlike the pump module 4 out 2 is a membrane 21 thereby formed by a magnetorheological elastomeric material, said magnetorheological elastomeric material consists of an elastomer with nanoscale particles introduced therein. In a magnetic field, a force acts on these particles, which in turn causes the desired, segmental deflection of the membrane 21 to represent a, analogous to in 3 described conveying movement, can be displayed. Otherwise, this corresponds to 4 illustrated pump module 4 ' the pump module 4 out 2 ,

Furthermore, goes from the 5 a further, alternative embodiment possibility of a pump module 4 '' which is also used instead of the pump modules 4 to 6 off at the positive displacement pump 1 Application can be found. In contrast to the embodiment according to 2 the actuator stages A1 to A6 are in this case formed by paired and opposite electrodes E1.1 to E6.2. These electrodes E1.1 to E6.2 can in turn individually via the power electronics 13 be controlled to represent a peristaltic conveying movement. At a, caused by the individual electrodes E1.1 to E6.2 electric field, a sectionally deflection of a membrane 22 In the present case, this is formed from an electrorheological elastomer material which consists of an elastomer with nanoscale particles introduced therein. Under the action of an electric field acts on these particles, a force, which in turn causes the partial deflection of the membrane 22 can be caused. Otherwise corresponds to the design of the pump module 4 '' in 5 again the variant of a pump module 4 out 2 ,

Finally, it is still in 6 a schematic view of a positive displacement pump according to a second embodiment of the invention shown. Unlike the variant off 1 are the pump modules 4 to 6 not arranged in a parallel circuit, but placed in the manner of a series circuit in the flow direction one behind the other. For this purpose, the inlet 7 of the pump module 4 with the inlet side 2 connected to the positive displacement pump, during its outlet 10 with the inlet 8th of the pump module 5 is coupled. The outlet 11 of the pump module 5 turn stands with the inlet 9 of the pump module 6 in connection, its outlet 12 with the outlet side 3 the positive displacement pump is coupled. Here is the respective outlet 10 respectively. 11 respectively. 12 only on an upper side of the respective pump module 4 respectively. 5 respectively. 6 provide, ie only the respective overhead housing part 15 to penetrate centrally with an axially extending through hole. Incidentally, the embodiment of the positive displacement pump corresponds 6 but the variant 1 ,

By means of the individual embodiments of pump modules 4 to 6 respectively. 4 ' respectively. 4 '' is a promotion of a medium with a simple structure and at the same time reliable operation possible. These pump modules can be interconnected in any way for the design of a positive displacement pump. In particular, an application in the area of a fore pump or pre-pump stage of a turbomolecular pump comes into consideration.

LIST OF REFERENCE NUMBERS

1

pump housing

2

inlet side

3

outlet

4, 4 ', 4' '

pump module

5

pump module

6

pump module

7

inlet

8th

inlet

9

inlet

10

outlet

11

outlet

12

outlet

13

power electronics

14

casing

15

housing part

16

housing part

17

flow channel

18

membrane

19, 19 '

delivery chamber

20, 20 '

delivery chamber

21

membrane

22

membrane

A1 to A6

Aktorstufen

B1 to B6

sheet metal rings

M1.1 to M6.2

solenoids

E1.1 to E6.2

electrodes

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• JP 03081585 A [0003, 0010]

Claims (10)

Pump module ( 4 . 5 . 6 ; 4 '; 4 '' ) with one, at least one flow channel ( 17 ) limiting housing ( 14 ), wherein the at least one flow channel ( 17 ) at least one inlet ( 7 . 8th . 9 ) with at least one outlet ( 10 . 11 . 12 ) and each receives a pump device oriented in the flow direction, which can be deflected in sections via individually actuatable actuators, and wherein a medium to be conveyed within at least one delivery chamber ( 20 . 21 ) which can be enclosed by sequential activation of the actuators between sections of the pumping device and per respective peripheral sections of the at least one flow channel (FIG. 17 ) capsulebar and in the course of a conveying movement between the at least one inlet ( 7 . 8th . 9 ) and the at least one outlet ( 10 . 11 . 12 ) is movable, characterized in that the actuators from the housing ( 14 ) are formed and that in each case on both sides of the flow channel opposing actuators form Aktorstufen (A1 to A6), which are arranged successively in the flow direction, wherein the pumping device as an elastic membrane ( 18 ; 21 ; 22 ), which by controlling one actuator each of the individual actuator stages (A1 to A6), each with an associated section to each an associated peripheral portion of the at least one flow channel ( 17 ) can be applied. Pump module ( 4 . 5 . 6 ; 4 ' ) according to claim 1, characterized in that the actuators are formed by magnetic coils (M1.1 to M6.2). Pump module ( 4 . 5 . 6 ; 4 ' ) according to claim 2, characterized in that the membrane ( 18 ; 21 ) consists of a magnetorheological elastomeric material or is formed of an elastomeric material, in which in the, the actuator stages (A1 to A6) associated sections each a ferromagnetic material is introduced. Pump module ( 4 '' ) according to claim 1, characterized in that the actuators are formed by electrodes (E1.1 to E6.2). Pump module ( 4 '' ) according to claim 4, characterized in that the membrane ( 22 ) of an electrorheological elastomeric material ( 23 ) consists. Pump module ( 4 . 5 . 6 ; 4 '; 4 '' ) according to claim 1, characterized in that the housing ( 14 ) of at least two housing parts ( 15 . 16 ), that the housing parts ( 15 . 16 ) and the intermediate membrane ( 18 ; 21 ; 22 ) are configured as discs of circular cross-section, and that the at least one inlet ( 7 . 8th . 9 ) is provided radially on the outside and via the flow channel ( 17 ) with the at least one outlet ( 10 . 11 . 12 ), which is centrally placed in the radial direction. Pump module ( 4 . 5 . 6 ; 4 '; 4 '' ) according to claim 1, characterized in that the actuator stages (A1 to A6) are placed in the flow direction equidistant or at different distances from each other. Positive displacement pump for delivering a fluid, in particular a backing pump of a turbo pump, comprising at least one pump module ( 4 . 5 . 6 ; 4 '; 4 '' ) according to any one of the preceding claims. Positive displacement pump according to claim 8, characterized in that in a pump housing ( 1 ) several pump modules ( 4 . 5 . 6 ) are arranged in a series and / or parallel connection. Positive displacement pump according to claim 8, characterized in that the actuators of the at least one pump module ( 4 . 5 . 6 ; 4 '; 4 '' ) via power electronics ( 13 ) are controllable.

Images