EP3988790A1 - Cartridge system and eccentric screw pump - Google Patents

Abstract

A cartridge system (16) for an eccentric screw pump (1), with a cartridge (17) for receiving a medium (M) to be metered, a stator (12) provided on the cartridge (17), which is used for metering the medium (M). a rotor unit (8) of the eccentric screw pump (1), and a plug (45) movably mounted in the cartridge (17) for sealing the cartridge (17) in a fluid-tight manner, the plug (45) comprising a rotor opening (46) through which the rotor unit (8) can be passed through.

Description

The present invention relates to a cartridge system for an eccentric screw pump and an eccentric screw pump, in particular a 3D print head, with such a cartridge system.

Progressing cavity pumps include a stator and a rotor rotating in the stator. When the rotor rotates, a medium to be metered is conveyed by the interaction of the rotor with the stator in a longitudinal direction of the eccentric screw pump away from a drive device of the eccentric screw pump according to the endless piston principle. The delivery volume per unit of time depends on the speed, size, pitch and geometry of the rotor. With such eccentric screw pumps, high-precision metering processes with a high degree of repeatability are possible. For this reason, progressing cavity pumps are suitable for use as print heads for additive or generative manufacturing.

In additive manufacturing or 3D printing, a component is built up in layers from a liquid, powder or paste-like material or medium. For example, if different formulations of the medium to be printed are tested, it is usually necessary to disassemble the entire progressing cavity pump, which is laborious and time-consuming, and to clean the components that come into contact with the medium, such as the rotor and the stator. It is therefore desirable for the eccentric screw pump to be cleaned as quickly and easily as possible.

Against this background, one object of the present invention is to provide an exchangeable cartridge system for an eccentric screw pump.

Accordingly, a cartridge system for an eccentric screw pump is proposed. The cartridge system comprises a cartridge for receiving a medium to be metered, a stator provided on the cartridge, which cooperates with a rotor unit of the eccentric screw pump to meter the medium, and a plug movably mounted in the cartridge for fluid-tight sealing of the cartridge, the plug having a rotor opening includes, through which the rotor unit can be passed.

The fact that the movably mounted stopper is provided in the cartridge prevents the medium to be metered from being contaminated. On the other hand, it is ensured that a drive device of the eccentric screw pump cannot be contaminated with the medium. Thus, all components in contact with the medium can be replaced by simply replacing the entire cartridge system. Contamination of the drive unit is not to be expected. This significantly simplifies the cleaning of the progressing cavity pump.

The progressing cavity pump preferably includes the rotor unit. However, the rotor unit can also be part of the cartridge. The rotor unit comprises a flexible shaft or flex shaft which is coupled to the drive mechanism of the progressing cavity pump. The flex shaft can also be referred to as a flexible shaft or cardan shaft. The flex shaft can also be a flexible rod, in particular a plastic flexible rod, or be referred to as such. In this case, the flex shaft can be made of a polyetheretherketone (PEEK), polyethylene (PE) or the like, for example. A rotor is provided on the front side of the flexible shaft, which interacts with the stator.

The stator preferably comprises an elastically deformable inner part or elastomer part with a central opening. The breakthrough preferably includes a helical or snail-shaped inner contour. In the stator is accommodated the rotatable rotor, which includes a corresponding to the inner part screw-shaped or snail-shaped outer contour. In addition to the exchangeable cartridge system, the progressing cavity pump also includes the previously mentioned drive device.

The rotor is driven via the flexible shaft by a drive unit, in particular an electric motor, of the drive device. The drive unit drives a drive shaft of the drive device, which is coupled to the rotor unit. The drive shaft can be rigidly connected to the rotor by means of the aforementioned flexible shaft or flex shaft. When the rotor rotates in the stator, the medium is conveyed away from the drive shaft according to the endless piston principle by the interaction with the inner part of the stator in a longitudinal direction of the eccentric screw pump. The delivery volume per unit of time depends on the speed, size, pitch and geometry of the rotor.

During operation of the eccentric screw pump, the rotor unit preferably performs an eccentric movement in the rotor opening. However, this is not mandatory. A purely rotational movement could also be provided. In this case, a joint or the aforementioned flex shaft is to be provided after stuffing, i.e. in the medium.

The cartridge is preferably cylindrical. In particular, the cartridge is a disposable syringe. This means that the cartridge system is preferably a disposable item. Alternatively, the cartridge system can also be used several times. The cartridge preferably has a Luer lock connection on the front side. This makes it easy to connect a nozzle to the cartridge. The cartridge can also be filled via the Luer lock connection.

In the present case, the fact that the stator is “provided” on the cartridge can mean that the stator is firmly connected to the cartridge. Alternatively, however, the stator can also simply be inserted into the cartridge or the like. This means that the stator can also be detachably connected to the cartridge. The stopper is mounted in the cartridge so that it can move linearly along the aforementioned longitudinal direction. The stopper follows the medium when dosing the medium. The rotor breakthrough is preferably provided centrally on the plug. The rotor breakthrough can be a stepped bore.

The medium can be, for example, an adhesive or sealant, water, an aqueous solution, a paint, a suspension, a viscous raw material, an emulsion or a fat. The medium can also be a gel or alginate. The medium can comprise cells, in particular human, animal or plant cells. The medium can be liquid or pasty. A paste or a pasty product is to be understood as meaning a solid-liquid mixture, in particular a suspension, with a high solids content. For example, the product can contain fillers, for example so-called microballoons, fibrous, in particular short-fibrous, fractions or the like.

The cartridge system or the cartridge can include an RFID chip (Radio Frequency Identification). In this way, in particular, a geometry of the stator can be recognized in order to be able to assign the appropriate rotor to the stator, for example. It is thus possible, for example, to identify a size. Furthermore, this also makes batch recognition of the medium received in the cartridge possible.

The cartridge system or the cartridge can also have a QR code (Quick Response) that is lasered into the cartridge, for example. This can be used to identify the medium held in the cartridge, for example. Information can then be read out, for example be, which allows conclusions to be drawn about the contents of the cartridge, namely the medium. For example, a batch recognition, a statement about the service life or the durability of the medium, a product tracking or the like is possible.

According to one embodiment, the stator and the cartridge are designed in one piece, in particular in one piece of material, or the stator and the cartridge are connected to one another in a form-fitting, force-fitting and/or cohesive manner.

In the present case, "in one piece" or "in one piece" is to be understood in particular as meaning that the stator and the cartridge form a common component and are not composed of different components. "One-piece material" means here that the stator and the cartridge are made of the same material throughout. Alternatively, however, the stator and the cartridge can also be two separate components which are connected to one another in a form-fitting, force-fitting and/or cohesive manner.

A form-fitting connection is created by the meshing or rear engagement of at least two connection partners, in this case the stator and the cartridge. For this purpose, for example, snap hooks or the like can be provided on the stator and on the cartridge. A non-positive connection requires a normal force on the surfaces to be connected. Force-locking connections can be realized by frictional locking. The mutual displacement of the surfaces is prevented as long as the counterforce caused by the static friction is not exceeded. For example, the stator is pressed into the cartridge. In the case of material connections, the connection partners are held together by atomic or molecular forces. Cohesive connections are non-detachable connections that can only be broken by destroying the connection means and/or the connection partner separate. For example, the stator is glued or vulcanized into the cartridge.

The stator can be made in one piece. However, the stator can also be designed in two pieces and has, for example, an inner part made of silicone, which has the snail-shaped opening, and an outer part, which is made of a different plastic material than the inner part. For example, the stator can have an elastomer on the inside and any desired thermoplastic on the outside. Alternatively, the stator can also be made from two different thermoplastics. The rear of the stator, ie facing the plug, can have a cone-shaped geometry. However, this is not mandatory.

According to a further embodiment, the rotor opening is closed with the aid of a diaphragm facing the stator.

The membrane can be pierced with the help of the rotor unit as soon as the cartridge system is mounted on the drive device. For this purpose, the rotor can have a tip, with the help of which the membrane is pierced. Alternatively, the membrane can also be pierced with the help of the rotor unit before the cartridge system is mounted on the drive device. In this case, the rotor unit is only connected to the drive device after the rotor unit has been inserted into the rotor opening.

According to a further embodiment, the membrane comprises a perforation, the perforation preferably dividing the membrane into a plurality of membrane sections.

The number of membrane sections is fundamentally arbitrary. For example, two, three or four membrane sections are provided. With the help of perforation it is possible to prevent parts of the membrane from tearing off when the rotor pierces the same and contaminating the medium. The perforation ensures that the membrane tears open evenly. The perforation can be cross-shaped, for example, and have two perforation sections crossing one another.

According to a further embodiment, the stopper comprises a pressure ring through which the rotor opening is passed and on which the membrane is provided.

The pressure ring preferably has the geometry of half an O-ring. The membrane is in one piece, in particular in one piece of material, connected to the pressure ring. The pressure ring runs completely around the rotor unit and constricts it. This provides a reliable sealing of the plug with respect to the rotor unit on the medium side. The pressure ring also acts as a tear stop if the membrane is pierced with the help of the rotor unit.

According to a further embodiment, the plug comprises a stiffening ring, remote from the pressure ring, through which the rotor opening is passed.

The stiffening ring preferably has a rectangular geometry in cross section. A rounding is provided at a transition from the stiffening ring into the rotor opening. The rounding makes it easier to insert the rotor unit into the rotor opening.

According to a further embodiment, at least one circumferential annular groove is provided on the rotor opening.

The number of annular grooves is basically arbitrary. For example, two or three annular grooves are provided. The annular grooves together form a labyrinth seal which provides a reliable seal of the plug against the rotating rotor assembly. Furthermore, the annular grooves also serve as a receiving area for displaced material of the plug when the rotor unit performs an eccentric movement in the rotor opening. That is, the plug follows the movement of the rotor unit. This is achieved by selecting the appropriate material for the stopper.

According to a further embodiment, the plug has a circumferential first sealing lip facing away from the stator, which rests on the inside of the cartridge, and/or the plug has a circumferential second sealing lip facing the stator, which also rests on the inside of the cartridge.

The first sealing lip is preferably acted upon by compressed air and is thus pressed against the cartridge on the inside. The second sealing lip ensures, on the one hand, that the plug is sealed radially in relation to the cartridge and, on the other hand, that the medium is wiped off on the inside of the cartridge.

According to a further embodiment, the second sealing lip has greater rigidity than the first sealing lip.

In the present case, the “stiffness” is to be understood as meaning the resistance of the respective sealing lip to deformation. The rigidity can be influenced, for example, by a suitable geometry or a suitable choice of material. For example, the second sealing lip has thicker walls than the first sealing lip. This results in a higher rigidity of the second sealing lip.

According to a further embodiment, the first sealing lip extends further out of the plug at the end face than the second sealing lip.

That is, the first sealing lip is higher than the second sealing lip. However, the first sealing lip preferably has thinner walls than the second sealing lip.

According to a further embodiment, the cartridge system also includes the rotor unit, which is guided through the rotor opening.

That is, the rotor unit can be an integral part of the cartridge system. In this case, the rotor unit is detachably connected to the drive device. When the cartridge system is removed from the drive device, the connection between the rotor unit and the drive device is preferably also released at the same time.

According to a further embodiment, the rotor unit is permanently connected to the cartridge and/or the plug.

This can prevent the rotor unit from being used multiple times. Alternatively, however, the rotor unit can also be detachably connected to the cartridge and the plug. In the latter case, the rotor unit can be used several times. For non-detachable connection of the rotor unit to the cartridge, a cover closing the cartridge at the back can be provided, for example, which has an opening through which the rotor unit is passed. The rotor unit can have latching hooks or snap hooks, which can be pushed through the opening. As soon as the snap hooks have passed through the opening, the rotor unit is firmly connected to the cartridge and can no longer be separated from it.

According to a further embodiment, the rotor assembly is completely encapsulated by the cartridge.

This means, on the one hand, that the rotor unit cannot be separated from the cartridge and, on the other hand, that direct contact between the rotor unit and the drive device is not possible and not necessary. In this case, the rotor unit can be driven by the drive device, for example with the aid of a magnetic coupling. The encapsulation can take place by sealing the cartridge in a fluid-tight manner at the rear. A cover can be provided for this purpose.

According to a further embodiment, the rotor unit includes an interface for coupling the rotor unit to a counter-interface of the drive device of the eccentric screw pump.

The interface and the counter-interface serve to transmit torque from the drive device to the rotor unit. The interface can have, for example, two wrench flats arranged parallel to one another. In this case, the mating interface has two key faces that correspond to it. The cross-section of the rotor unit can be rectangular, star-shaped, triangular or square, or round. The interface and the counter-interface may include magnets to implement the aforementioned magnetic coupling.

According to a further embodiment, the interface comprises a latching lug which latches into the counter-interface when the rotor unit is connected to the drive device.

With the help of the detent, a form-fitting connection of the rotor unit to the mating interface is thus achieved. The counter interface is provided on the drive shaft of the drive device. In the event that the cartridge system is a disposable item, the detent is designed such that this is sheared off or broken off when the rotor unit is separated from the drive device. This means that the rotor unit can no longer be connected to the drive device. Alternatively, the detent can also deform elastically. In this case, the rotor unit can be used repeatedly.

According to a further embodiment, the interface comprises a plurality of elastically deformable arm sections on which the latching lug is provided.

For example, two or four arm sections are provided. The number of arm sections is basically arbitrary. Slots are provided between the arm portions. This results in a slit-shaped or cross-slit-shaped geometry. Alternatively, the interface can also have a polygonal, rectangular, triangular or star-shaped geometry.

According to a further embodiment, the cartridge system also includes the medium accommodated in the cartridge.

The medium can be, for example, an alginate, bone wax or any other biological or medicinal material. The medium can contain human, animal or plant cells. The medium can furthermore also comprise bacteria or viruses. A suitable medium can be selected depending on the use of the cartridge system in biomedicine, pharmaceutical technology or industry. The medium can also be a cyanoacrylate, for example.

According to a further embodiment, the stopper comprises an indicator which changes its state after the cartridge system has been used.

In particular, the indicator changes its status after a single use of the cartridge system. The indicator can be a dye, for example be. The change in state can be a color change. The condition may change with exposure to light and/or moisture. The indicator can thus be used to show that the cartridge system has already been used once. Furthermore, the indicator can only change its state after a predetermined time. Furthermore, the indicator can also be designed in such a way that it only changes its status after a predetermined number of uses of the cartridge system.

According to a further embodiment, the stopper is made of an air-permeable or air-impermeable material.

In the event that the plug is made of an air-permeable material, degassing of the medium is possible under the pressure of the plug on the medium. This is particularly important when processing liquid silicones or acrylates. Thus, bubbles formed in the medium can pass through the air-permeable material. For this purpose, the stopper consists of a porous, open-pored, gas-permeable material. For example, polytetrafluoroethylene (PTFE), polyethylene (PE), or other suitable material may be used. This allows gas bubbles trapped in the medium to escape through the porous material. The porosity of the material is selected, for example, in the range from 1 μm to 50 nm, preferably in the range from 10 μm to 50 nm, more preferably in the range from 20 μm to 50 nm. Thus, the viscous medium cannot escape through the stopper. Alternatively, the stopper may also have a built-in air-permeable membrane.

Furthermore, an eccentric screw pump, in particular a 3D print head, with a drive device and such an exchangeable cartridge system is proposed, which is detachably connected to the drive device.

A bayonet catch, for example, can be provided for the detachable connection of the cartridge system to the drive device. The medium is pressurized via the stopper with the help of compressed air or a spring element. Furthermore, an eccentric insert can also be provided in the stopper. The pitch of this insert is adapted to the volumetric quantity and therefore also to the stopper speed. A spindle drive is thus realized. The stopper is then positively controlled and thus follows the medium.

The progressing cavity pump can be mains-operated. However, the eccentric screw pump can also be battery operated. As a result, the progressing cavity pump is independent of a power grid. The progressing cavity pump can thus work independently as a handheld device. For example, the progressing cavity pump can be used to dose soldering paste at a manual workstation. The eccentric screw pump can thus be used in the manner of a pipetting device or pipetting aid, with the difference that the eccentric screw pump can also be used to meter highly viscous media. Furthermore, such a self-sufficient eccentric screw pump can also be used to treat quick wounds, for example to treat emergency personnel in the field, or in the operating room. In this case, for example, waxes, in particular bone waxes, adhesives, denture materials, artificial skin or the like can be dosed.

As used herein, "a" is not necessarily to be construed as being limited to exactly one element. Rather, several elements, such as two, three or more, can also be provided. Any other count word used here should also not be understood to mean that there is a restriction to precisely the stated number of elements. Rather, numerical deviations upwards and downwards are possible, unless otherwise stated.

Other possible implementations of the cartridge system and/or the eccentric screw pump also include combinations of features or embodiments described above or below with regard to the exemplary embodiments that are not explicitly mentioned. The person skilled in the art will also add individual aspects as improvements or supplements to the respective basic form of the cartridge system and/or the eccentric screw pump.

Fig. 1

zeigt eine schematische perspektivische Ansicht einer Ausführungsform einer Exzenterschneckenpumpe;

Fig. 2

zeigt eine schematische Schnittansicht der Exzenterschneckenpumpe gemäß Fig. 1;

Fig. 3

zeigt eine weitere schematische perspektivische Ansicht der Exzenterschneckenpumpe gemäß Fig. 1;

Fig. 4

zeigt eine weitere schematische perspektivische Ansicht der Exzenterschneckenpumpe gemäß Fig. 1;

Fig. 5

zeigt eine weitere schematische perspektivische Ansicht der Exzenterschneckenpumpe gemäß Fig. 1;

Fig. 6

zeigt eine schematische perspektivische Ansicht einer Ausführungsform eines Lagergehäuses für die Exzenterschneckenpumpe gemäß Fig. 1;

Fig. 7

zeigt die Detailansicht A gemäß Fig. 2;

Fig. 8

zeigt eine weitere schematische perspektivische Ansicht der Exzenterschneckenpumpe gemäß Fig. 1;

Fig. 9

zeigt eine weitere schematische perspektivische Ansicht der Exzenterschneckenpumpe gemäß Fig. 1;

Fig. 10

zeigt eine schematische perspektivische Ansicht einer Ausführungsform einer Schnittstelle einer Rotoreinheit für die Exzenterschneckenpumpe gemäß Fig. 1;

Fig. 11

zeigt eine schematische perspektivische Ansicht einer weiteren Ausführungsform einer Schnittstelle einer Rotoreinheit für die Exzenterschneckenpumpe gemäß Fig. 1;

Fig. 12

zeigt die Detailansicht B gemäß Fig. 2;

Fig. 13

zeigt eine schematische Teilschnittansicht einer Ausführungsform eines Kartuschensystems für die Exzenterschneckenpumpe gemäß Fig. 1;

Fig. 14

zeigt eine schematische Ansicht einer Ausführungsform eines Stopfens für das Kartuschensystem gemäß Fig. 13;

Fig. 15

zeigt eine schematische Schnittansicht des Stopfens gemäß Fig. 14;

Fig. 16

zeigt eine schematische Unteransicht des Stopfens gemäß Fig. 14;

Fig. 17

zeigt eine schematische Ansicht einer weiteren Ausführungsform eines Stopfens für das Kartuschensystem gemäß Fig. 13;

Fig. 18

zeigt eine schematische Schnittansicht des Stopfens gemäß Fig. 17;

Fig. 19

zeigt eine schematische Ansicht einer weiteren Ausführungsform eines Stopfens für das Kartuschensystem gemäß Fig. 13;

Fig. 20

zeigt eine schematische Schnittansicht des Stopfens gemäß Fig. 19;

Fig. 21

zeigt eine schematische Ansicht einer weiteren Ausführungsform eines Stopfens für das Kartuschensystem gemäß Fig. 13;

Fig. 22

zeigt eine schematische Schnittansicht des Stopfens gemäß Fig. 21;

Fig. 23

zeigt eine schematische perspektivische Ansicht einer Ausführungsform eines Befüllkonzept zum Befüllen des Kartuschensystems gemäß Fig. 13;

Fig. 24

zeigt eine schematische Schnittansicht einer weiteren Ausführungsform einer Exzenterschneckenpumpe;

Fig. 25

zeigt die Detailansicht C gemäß Fig. 24;

Fig. 26

zeigt eine schematische Teilschnittansicht einer weiteren Ausführungsform eines Kartuschensystems für die Exzenterschneckenpumpe gemäß Fig. 1 oder Fig. 24;

Fig. 27

zeigt die Detailansicht D gemäß Fig. 26; und

Fig. 28

zeigt eine schematische Teilschnittansicht einer weiteren Ausführungsform eines Kartuschensystems für die Exzenterschneckenpumpe gemäß Fig. 1 oder Fig. 24.

Further advantageous configurations and aspects of the cartridge system and/or the eccentric screw pump are the subject matter of the subclaims and the exemplary embodiment of the cartridge system and/or the eccentric screw pump described below. The cartridge system and/or the eccentric screw pump are explained in more detail below on the basis of preferred embodiments with reference to the enclosed figures.

1

shows a schematic perspective view of an embodiment of a progressing cavity pump;

2

shows a schematic sectional view of the progressing cavity pump according to FIG 1 ;

3

shows a further schematic perspective view of the progressing cavity pump according to FIG 1 ;

4

shows a further schematic perspective view of the progressing cavity pump according to FIG 1 ;

figure 5

shows a further schematic perspective view of the progressing cavity pump according to FIG 1 ;

6

shows a schematic perspective view of an embodiment of a bearing housing for the eccentric screw pump according to FIG 1 ;

7

shows the detailed view A according to 2 ;

8

shows a further schematic perspective view of the progressing cavity pump according to FIG 1 ;

9

shows a further schematic perspective view of the progressing cavity pump according to FIG 1 ;

10

FIG. 12 shows a schematic perspective view of an embodiment of an interface of a rotor unit for the progressive cavity pump according to FIG 1 ;

11

FIG. 12 shows a schematic perspective view of another embodiment of an interface of a rotor unit for the progressive cavity pump according to FIG 1 ;

12

shows the detailed view B according to 2 ;

13

shows a schematic partial sectional view of an embodiment of a cartridge system for the eccentric screw pump according to FIG 1 ;

14

FIG. 1 shows a schematic view of an embodiment of a plug for the cartridge system according to FIG 13 ;

15

shows a schematic sectional view of the stopper according to FIG 14 ;

16

shows a schematic bottom view of the stopper according to FIG 14 ;

17

shows a schematic view of a further embodiment of a plug for the cartridge system according to FIG 13 ;

18

shows a schematic sectional view of the stopper according to FIG 17 ;

19

shows a schematic view of a further embodiment of a plug for the cartridge system according to FIG 13 ;

20

shows a schematic sectional view of the stopper according to FIG 19 ;

21

shows a schematic view of a further embodiment of a plug for the cartridge system according to FIG 13 ;

22

shows a schematic sectional view of the stopper according to FIG 21 ;

23

shows a schematic perspective view of an embodiment of a filling concept for filling the cartridge system according to FIG 13 ;

24

shows a schematic sectional view of a further embodiment of an eccentric screw pump;

25

shows the detailed view C according to 24 ;

26

shows a schematic partial sectional view of a further embodiment of a cartridge system for the eccentric screw pump according to FIG 1 or 24 ;

27

shows the detailed view D according to 26 ; and

28

shows a schematic partial sectional view of a further embodiment of a cartridge system for the eccentric screw pump according to FIG 1 or 24 .

Elements that are the same or have the same function have been provided with the same reference symbols in the figures, unless otherwise stated.

the 1 shows a schematic perspective view of an embodiment of an eccentric screw pump 1 for metering a liquid or pasty medium. the 2 shows a schematic sectional view of the eccentric screw pump 1. The 3 shows a further schematic perspective view of the eccentric screw pump 1. The 4 shows a further schematic perspective view of the eccentric screw pump 1. The figure 5 shows a further schematic perspective view of the eccentric screw pump 1. Below is on the Figures 1 to 5 referenced at the same time.

The eccentric screw pump 1 includes a drive device 2. The drive device 2 has a drive unit 3, which can include an electric motor. The drive unit 3 is accommodated in a housing 4 . The housing 4 can be tubular. A bearing housing 5 is attached to the front of the housing 4 . The bearing housing 5 can be screwed to the housing 4 with the aid of a connecting element 6, for example.

The drive unit 3 drives a drive shaft 7 of the drive device 2 . The drive shaft 7 in turn drives a rotor unit 8 . The rotor unit 8 comprises a flexible shaft or flex shaft 9, which is coupled to the drive shaft 7 by means of an interface, and a helical rotor 10, which is attached to the front of the flexible shaft 9. The rotor 10 is thus driven by the flex shaft 9 .

The flex shaft 9 is elastically deformable and enables an eccentric movement of the rotor 10. The flex shaft 9 is used to transmit torque from the drive unit 3 to the rotor 10. The flex shaft 9 can be a wire cable which is coated or encased with a plastic material, for example. Instead of the flexible shaft 9, a universal joint or cardan joint can also be provided, which also enables an eccentric movement of the rotor 10. The flex shaft 9 can also be a flexible rod, in particular a plastic flexible rod, or be designated as such. In this case, the flex shaft 9 can be made of a polyetheretherketone (PEEK), polyethylene (PE) or the like, for example. The flexible shaft 9 can have a diameter of 3 mm, for example. The rotor 10 has a tip 11 at the front.

The rotor 10 and the flexible shaft 9 can, for example, be designed in one piece, in particular in one piece of material. "In one piece" or "in one piece" means here that the flex shaft 9 and the rotor 10 form a common component and are not composed of different components. In the present case, “in one piece” means that the flex shaft 9 and the rotor 10 are made of the same material throughout. The rotor unit 8 is preferably a plastic component. For example, the rotor unit 8 can be a one-piece plastic injection molded component.

Alternatively, the flexible shaft 9 and the rotor 10 can also be two separate components that are plugged into one another, for example, and are thus either detachably or non-detachably connected to one another. For example, the flexible shaft 9 can be made of a metallic material and the rotor 10 can be made of a plastic. The flex shaft 9 can be coated with an elastomer. Also the rotor 10 can be made of a metallic material. The rotor 10 can be made of stainless steel, for example. However, the rotor 10 can also be designed as a plastic component or ceramic component and can have a wide variety of coatings.

The eccentric screw pump 1 also includes a preferably at least partially elastically deformable stator 12. In particular, the stator 12 is an elastically deformable elastomeric part with a central opening 13. The opening 13 preferably includes a helical or snail-shaped inner contour. The rotatable rotor 10 is accommodated in the stator 12 and comprises a helical or snail-shaped outer contour corresponding to the stator 12 . An air supply line 14 is provided on the bearing housing 5 and is in fluid communication with an air duct 15 provided in the bearing housing 5 and leading out of the end face of the bearing housing 5 .

When the rotor 10 rotates, the medium is conveyed away from the drive shaft 7 according to the endless piston principle through the interaction with the opening 13 of the stator 12 in a longitudinal direction L, which is oriented from the drive device 2 in the direction of the rotor 10 . The delivery volume per unit of time is dependent on the speed, size, pitch and geometry of the rotor 10.

Eccentric screw pumps 1 are particularly suitable for conveying a large number of media, in particular viscous, highly viscous and abrasive media. The progressing cavity pump 1 belongs to the group of rotating displacement pumps. The main parts of the progressing cavity pump 1 are the drive device 2, the rotatable rotor 10 and the fixed stator 12 in which the rotor 10 rotates. The rotor 10 is designed as a type of round thread screw with an extremely large pitch, large thread depth and small core diameter.

The at least partially elastically deformable stator 12 preferably has one more thread turn than the rotor 10 and twice the pitch length of the rotor 10. This leaves conveying chambers between the stator 12 and the rotor 10 rotating therein and also moving radially, which continuously extend from an inlet side of the Stators 12 move to an exit side thereof. Valves to limit the pumping chambers are not required. The size of the delivery chambers and thus the theoretical delivery rate depends on the pump size. A 360° rotation of the rotor unit 8 with a free outlet results in the volumetric flow rate per revolution. The pump delivery rate can thus be changed via the speed. The actual flow rate depends on the back pressure that occurs.

The medium to be metered always tries to equalize the pressure from high to low pressure. Since the seal between the rotor 10 and the stator 12 is not static, medium will always flow from the pressure side to the suction side. These "slip losses" can be seen on the basis of a characteristic curve as the difference between the theoretical and the actual flow rate.

The shape of the pumping chambers is constant so that the medium is not compressed. With a suitable design, such an eccentric screw pump 1 can be used to convey not only fluids but also solids. The shearing forces that act on the material to be conveyed are very small, so that plant, animal and human cells, for example, can also be conveyed without being destroyed. A particular advantage of such an eccentric screw pump 1 is that the eccentric screw pump 1 delivers continuously and with little pulsation. This makes them suitable for use in potting plants. Even highly viscous and abrasive media can be pumped without any problems.

With the progressing cavity pump 1, a wide variety of media can be conveyed gently and with low pulsation. The spectrum of media ranges from water to media that no longer flow by themselves. Since the flow rate is proportional to the speed of the rotor 10, the eccentric screw pump 1 can be used very well for dosing tasks in conjunction with appropriate measurement and control technology.

The progressing cavity pump 1 combines many positive properties of other pump systems. Like the centrifugal pump, the progressing cavity pump 1 has no suction and pressure valves. Like the piston pump, the progressive cavity pump 1 has excellent self-priming performance. Like the diaphragm or peristaltic pump, the eccentric screw pump 1 can convey any type of inhomogeneous and abrasive media, including solids and fibrous materials.

Multi-phase mixtures are also conveyed safely and gently by the eccentric screw pump 1. Like the gear or screw pump, the eccentric screw pump 1 is able to cope with the highest viscosities of the medium. Like the piston, membrane, gear or screw pump, the progressing cavity pump 1 has a speed-dependent, continuous delivery flow and is therefore able to perform high-precision dosing tasks.

The eccentric screw pump 1 can in principle be used in all industrial sectors in which special conveying tasks have to be solved. Examples are environmental technology, especially pumping in the area of sewage treatment plants, the food industry, especially for high-viscosity media such as syrup, quark, yoghurt and ketchup, in the various low-germ processing stages, and the chemical industry, especially for safe pumping and dosing of aggressive, high-viscosity media and abrasive products.

With the eccentric screw pump 1, the exact dosing of different media is possible. A repeat accuracy of up to ± 1% can be achieved. Various embodiments of the eccentric screw pump 1 also allow two-component media to be discharged. Because of its design, namely that the rotor 10 moves in the medium and the interior volume of the suction side must be filled, such an eccentric screw pump 1 always has a certain dead space.

As previously mentioned, the rotor unit 8 includes the flex shaft 9 which is elastically deformable. This allows the rotor 10 to move eccentrically in the stator 12. It is also possible to implement this eccentric movement with the aid of joints, in particular universal joints or cardan joints. The stator 12 is subjected to a continuous load during operation, which is why it is subject to wear. This wear is compensated for by regularly replacing the stator 12, with the replacement intervals being determined by the media used and the process parameters.

With an eccentric screw pump 1 of this type, the medium to be conveyed has hitherto always been supplied from outside the eccentric screw pump 1 . Cartridges, hoses or the like can be provided for this purpose. The drive shaft 7 is sealed at an interface thereof with the drive unit 3 and must at least withstand the feed pressure or the pressure which is generated by the drive device 2 running backwards. The eccentric screw pump 1 is cleaned both by flushing it with cleaning liquid and by dismantling and manual cleaning. In many cases, heating or cooling of the eccentric screw pump 1 is possible.

In addition to the drive device 2 , the eccentric screw pump 1 includes a cartridge system 16 which is detachably connected to the drive device 2 . The cartridge system 16 includes a cartridge 17 which is designed as a plastic component, in particular as a plastic injection molded component. The cartridge 17 is in the form of a disposable syringe, for example. The cartridge 17 has a Luer lock connection 18 on the front. The rotor unit 8 can be part of the cartridge system 16 .

The cartridge 17 encloses a cylindrical interior 19 in which the medium to be explained later is accommodated. The interior 19 is a cartridge interior or can be referred to as such. The air duct 15 also opens into the interior space 19 . This means that the air supply 14 is in fluid connection with the interior space 19 via the air duct 15 provided in the bearing housing 5 and leading out of the end face of the bearing housing 5 .

Stator 12 is accommodated in interior space 19 . Stator 12 can be formed in one piece, in particular in one piece of material, with cartridge 17 . For example, the cartridge 17 and the stator 12 form a one-piece, in particular a one-piece plastic injection molded component. However, the stator 12 can also be made of a different material from the cartridge 17 . For example, the stator 12 is made of liquid silicone rubber or LSR, any elastomer, an engineering plastic, or the like.

The stator 12 can be molded onto the cartridge 17 in a plastic injection molding process. A two-component plastic injection molding process can be used for this purpose, for example. However, the stator 12 can, for example, also simply be pressed into the cartridge 17 and thus be connected to it in a non-positive and/or positive manner. A form-fitting one Connection is created by at least two connection partners engaging in one another or behind, in this case the stator 12 and the cartridge 17. For this purpose, for example, snap-in hooks or snap-in hooks can be provided on the stator 12 and/or the cartridge 17.

A non-positive connection, on the other hand, requires a normal force on the surfaces to be connected. Force-locking connections can be realized by frictional locking. The mutual displacement of the surfaces is prevented as long as the counterforce caused by the static friction is not exceeded. In this case, the stator 12 is preferably pressed into the cartridge 17 .

The stator 12 can also be connected to the cartridge 17 with a material connection. This can be done, for example, by the previously mentioned two-component plastic injection molding process. In the case of material connections, the connection partners are held together by atomic or molecular forces. Cohesive connections are non-detachable connections that can only be separated by destroying the connection means and/or the connection partner. For example, the stator 12 can be glued into the cartridge 17 .

The stator 12 is provided on the front side of the cartridge 17 . Away from the Luer lock connection 18 , the cartridge 17 comprises two arm sections 20 , 21 which can be brought into positive engagement with the bearing housing 5 in order to connect the cartridge system 16 to the drive device 2 . Furthermore, the cartridge 17 has a cone-shaped engagement section 22 ( 7 ).

As the 6 shows, the bearing housing 5 comprises a conical counter-engagement portion 23 which is suitable for engaging in the engagement portion 22. Of the Conical counter-section 23 includes a central opening 24 through which the drive shaft 7 is passed. On the outside, an annular groove 25 runs around the counter-engagement section 23, in which an O-ring 26 ( 7 ) recorded. The bearing housing 5 also includes a bayonet lock 27 which enables the cartridge system 16 to be connected to the drive device 2 quickly and easily. The bayonet catch 27 comprises two slot-shaped recesses 28, 29 provided on the bearing housing 5.

As the Figures 3 to 5 show, the cartridge system 16 is first attached to the cone-shaped counter-engagement portion 23, as a result of which it engages in the engagement portion 22 of the cartridge 17. The cartridge system 16 is then rotated 90° clockwise relative to the drive device 2 . The arm sections 20, 21 come into engagement with the recesses 28, 29 of the bayonet catch 27, as a result of which the engagement section 22 of the cartridge 17 is pushed further onto the counter-engagement section 23 until the O-ring 26 seals against the cartridge 17 and ends 30 ( 7 ) of the arm sections 20, 21 on an end face 31 ( Figures 6 and 7 ) of the bearing housing 5. The O-ring 26 is compressed in the process, as a result of which a fluid-tight sealing of the bearing housing 5 with respect to the cartridge 17 is achieved. In the present case, “fluid-tight” means in particular both gas-tight and liquid-tight. The interior 19 of the cartridge 17 can now be pressurized via the air duct 15 .

The sealing of the cartridge system 16 with the aid of the O-ring 26 on the cone-shaped counter-engagement section 23 makes it easy to mount the cartridge system 16 on the drive device 2 . When the cartridge system 16 is rotated in relation to the bearing housing 5, the cartridge system 16 is pulled against the bearing housing 5 due to the bayonet lock 27 and thus seals off the cartridge 17 with the aid of the O-ring 26. Of the The cone-shaped counter-engagement section 23 also enables the cartridge system 16 to be centered on the bearing housing 5.

The counter-engagement section 23 thus fixes the cartridge system 16 on the drive device 2. The use of the bayonet lock 27 reliably prevents the cartridge system 16 from becoming detached from the drive device 2 unintentionally. Sealing takes place via the conical engagement section 22 and the conical counter-engagement section 23 and the O-ring 26. The bayonet catch 27 can be used to exert uniform pressure on the cartridge 17 so that the end faces 30, 31 are pressed against one another. The geometry of the counter-engagement section 23 is adapted to the engagement section 22 of the cartridge 17 .

the 8 shows a further schematic perspective view of the eccentric screw pump 1, wherein the cartridge 17 is not shown. As previously mentioned, between the rotor unit 8, in particular the flex shaft 9, and the drive shaft 7 there is an interface 32 ( 10 and 11 ) intended. As the 10 and 11 show, the interface 32 comprises two key faces 33 arranged opposite one another and a plurality of elastically deformable arm sections 34, 35. In this way, as in FIG 10 shown, two such arm portions 34, 35 may be provided.

As the 11 shows, four arm sections 34 to 37, for example, can also be provided. Slots 38, 39 are provided between the arm portions. This enables an elastic deformation of the arm sections 34 to 37. On the arm sections 34 to 37 there is a ring-shaped circumferential detent 40. The detent 40 is interrupted at the slots 38,39. The provision of two slots 38, 39 or four arm cuts 34 to 37 is optional and is particularly suitable for rotor units 8 that are made of a harder plastic.

As the 12 shows, the drive shaft 7 comprises a counter-interface 41 corresponding to the interface 32. The counter-interface 41 comprises key surfaces 42, 43 corresponding to the key surfaces 33. The key surfaces 33 and the key surfaces 42, 43 serve to transmit torque from the drive shaft 7 to the flexible shaft 9. The mating interface 41 also includes a shoulder 44 which is designed as a circumferential annular groove. The detent 40 engages in the paragraph 44 in a form-fitting manner.

To connect the rotor unit 8 to the drive device 2, the interface 32 of the rotor unit 8 is pushed into the interface 41 of the drive shaft 7, as in FIGS 8 and 9 shown. The arm sections 34 to 37 of the interface 32 deform in a spring-elastic manner until the detent 40 engages in the shoulder 44 of the counter-interface 41 in a form-fitting manner. To separate the rotor unit 8 from the drive device 2, the rotor unit 8 is pulled out of the drive shaft 7 so that the interface 32 and the counter-interface 41 separate from one another.

In the event that the rotor unit 8 is a disposable item, the detent 40 can be sheared off the interface 32 or break off. As a result, it is no longer possible to reconnect the rotor unit 8 to the drive device 2 . In the event that the rotor unit 8 is used several times, the arm sections 34 to 37 deform elastically when the rotor unit 8 is pulled out of the drive shaft 7, so that the locking lug 40 no longer engages positively with the shoulder 44 of the counter interface 41. The rotor unit 8 can now be pulled off the drive device 2 . Due to the fact that the detent 40 does not shear off in this case, the rotor unit 8 can also be used several times.

Now returning to that 2 the cartridge system 16 includes a plug 45 accommodated in the cartridge 17. The plug 45 is mounted in the cartridge 17 in a linearly displaceable manner along the longitudinal direction L. That is, the plug 45 can move along the longitudinal direction L and counter to the longitudinal direction L in the cartridge 17 . The rotor unit 8 , in particular the rotor 10 , is guided through the plug 45 . For this purpose, a rotor opening 46 that breaks through the plug 45 is provided.

The cartridge system 16 with the cartridge 17, the stator 12 and the plug 45 preferably forms a disposable or a disposable item. The cartridge system 16 can also include the rotor unit 8 , in particular the rotor 10 . However, this is not mandatory. Alternatively, the cartridge system 16 can also be used several times. In the latter case, the cartridge system 16 can be refilled.

Disposable process solutions, also known as single-use technologies, are used in particular to manufacture biopharmaceutical products. This means complete solutions from one-way systems, which are also referred to as single-use systems, for an entire process line. This may include, for example, media and buffer preparation, bioreactors, cell harvest, depth filtration, tangential flow filtration, chromatography, and virus inactivation.

Various defined media are required for biotechnical processes. These include nutrient solutions, cells, buffers for stabilizing the pH value, as well as acids and bases for adjusting and regulating the pH value during cultivation. All media used must be sterilized before use. For this purpose, two main processes are used in biotechnology: heat sterilization at at least 121 °C at 1 bar overpressure for at least 20 minutes and sterile filtration. For media that are heat sensitive components such as vitamins, proteins and peptides, sterile filtration is the method of choice.

The difference between the production of single-use media and buffers and conventional methods lies in the use of appropriate single-use products that are specially developed for this purpose, such as special bags, single-use mixing systems and filters, and appropriate pumps. In contrast to conventional filters, the filters used are pre-sterilized. In some cases, the bags, filters and pump heads are already connected to form a complete single-use system. The entire system is supplied connected and pre-sterilized to avoid contamination. In addition to the aforementioned single-use procedures, each of which is based on a basic process engineering operation, special methods and devices have been developed in the world of single-use biopharmaceutical production that are mainly only used here, such as sterile couplings and tube welding devices.

The disposable process solutions available are each to be regarded as a self-contained module. As part of a one-way production process, the basic process engineering operations required for the production and purification of the target product are connected in series. The preconfigured single-use systems, which consist of hoses, single-use tanks, pump pots and filtration or chromatography modules, are self-contained. Sterile connection technologies, usually hose connections, are therefore required to connect two consecutive process steps.

On the one hand there are mechanical one-way couplings, on the other hand there are devices with which thermoplastic hoses can be welded together in a sterile manner or existing connections can be severed and the hose ends can be welded. For connections through a wall special rapid transfer systems have been developed. At present, most production processes using single-use products are still so-called hybrid processes, in which single-use systems are combined with conventional stainless steel and glass systems. A distinction is made here between closed systems, in which the one-way systems are linked together in the order of the process steps, and station systems, in which the intermediate products are transported to the next process step using mobile containers.

In biopharmaceutical production, the term "single use" (often also referred to as "disposable") defines an item that is intended for single use. Usually this consists of a plastic material such as polyamide (PA), polycarbonate (PC), polyethylene (PE), polyethersulfone (PESU), polyoxymethylene (POM), polypropylene (PP), polytetrafluoroethylene (PTFE), polyvinyl chloride (PVC) , cellulose acetate (CA) or ethylene vinyl acetate (EVA), and is discarded after use. Accordingly, single-use technology (SUT) is to be understood as a technology based on single-use systems (SUS).

As the 13 shows, the plug 45 includes the rotor opening 46, through which the rotor unit 8, in particular the rotor 10, is passed. As the 13 furthermore shows, the stator 12 comprises an inner part 47, in particular an elastomer part, on which the opening 13 with the helical inner geometry is provided, and an outer part 48, which accommodates the inner part 47. The outer part 48 is tubular and takes the inner part 47 in itself. The inner part 47 is elastically deformable. For example, the inner part 47 can be made of a thermoplastic elastomer (TPE) and the outer part 48 can be made of a polyurethane (PU).

The stator 12 can be a one-piece or a multi-piece component. For example, the inner part 47 can be pressed into the outer part 48 . Alternatively, the inner part 47 and the outer part 48 can also be produced as a one-piece component in a two-component injection molding process. For example, the elastomer part 47 is made of a liquid silicone or LSR. The outer part 48 can be made of any thermoplastic material, such as PE, ABS, PP or the like. Alternatively, the elastomer part 47 can also be made of a thermoplastic material.

For example, the stator 12 is inserted, clipped, glued into the cartridge 17 or connected to it in some other way. In particular, the stator 12 can, as mentioned above, be designed in one piece, in particular in one piece of material, with the cartridge 17 . However, the stator 12 can also be removed from the cartridge 17 .

With the help of the air supply 14, the plug 45 can be subjected to an overpressure. A sterile filter or moisture filter can be provided on the air supply 14 . This can be provided both inside the bearing housing 5 and outside, for example in the air supply 14 .

Returning now to plug 45, as shown in FIGS Figures 14 and 15 shown, a cylindrical or barrel-shaped geometry. In particular, the stopper 45 is constructed rotationally symmetrically to a central or symmetrical axis 49 . The stopper 45 can be made, for example, from an LSR, a two-component silicone, PE, POM, PP, PTFE or from an elastomer. The stopper 45 can also be made of a porous, open-pored, gas-permeable material such as PTFE or PE. As a result, gas bubbles trapped in the medium can escape via the porous plug 45 . The porosity of the material is preferably in the range from 1 μm to 50 nm, for example in the range from 10 μm to 50 nm, more preferably in the range from 20 μm to 50 nm. Alternatively, the plug 45 can also include a built-in membrane.

Facing away from the stator 12 , the plug 45 includes a first sealing lip 50 that runs completely around the axis of symmetry 49 . The first sealing lip 50 rests against the cartridge 17 on the inside. Facing away from the first sealing lip 50 , the plug 45 includes a second sealing lip 51 , which also bears against the cartridge 17 on the inside. The second sealing lip 51 is placed on the medium side. The first sealing lip 50 is placed away from the medium. The second sealing lip 51 has a wiping function and is more rigid than the first sealing lip 50. Viewed along the axis of symmetry 49, the more flexible first sealing lip 50 extends further out of the plug 45 than the second sealing lip 51.

The rotor opening 46 comprises a plurality of annular grooves 52, 53 running around the axis of symmetry 49, which together form a labyrinth seal 54 in order to seal the flex shaft 9 and/or the rotor 10 against the plug 45 in a fluid-tight manner. With an eccentric movement of the flex shaft 9 in the rotor opening 46 displaced plug material is pressed into the annular grooves 52, 53. The number of annular grooves 52, 53 is arbitrary. For example, two such annular grooves 52, 53 can be provided. However, only one annular groove 52, 53 can also be provided.

On the upper side, ie facing away from the medium, the plug 45 comprises a stiffening ring 55 which runs completely around the axis of symmetry 49 and which is broken through by the rotor opening 46 . A rounding 56 is provided in a transition between the stiffening ring 45 and the rotor opening 46 , which makes it easier to insert the rotor unit 8 into the rotor opening 46 .

Facing the medium, ie facing away from the stiffening ring 55, a pressure ring 57 is provided. The pressure ring 57 constricts itself around the rotor unit 8 and seals it off. The pressure ring 57 is in the form of a halved O-ring. The rotor opening 46 is closed with the aid of a membrane 58 which is connected to the pressure ring 57 . The membrane 58 can be pierced with the help of the rotor 10, in particular with the help of the tip 11 of the rotor 10. If the membrane 58 is punctured, the pressure ring 57 ensures that the stopper 45 does not tear any further.

As the 16 shows, the membrane 58 comprises a plurality of membrane sections 59 to 62. The number of membrane sections 59 to 62 is arbitrary. For example, two, three or four membrane sections 59 to 62 can be provided. A performance 63 which is cross-shaped is provided between the membrane sections 59 to 62 . The perforation 63 comprises a first perforation section 64 and a second perforation section 65 which are placed perpendicular to each other and form the cross-shaped perforation 63 . The provision of the perforation 63 makes it possible to prevent parts of the membrane 58 from becoming detached when the rotor 10 pierces it.

The plug 45 seals both on the first sealing lip 50 and on the second sealing lip 51 with an overlap. This means that the sealing lips 50, 51 are compressed radially in the cartridge 17. At the same time, a wiping function on the side of the medium and on the inside of the cartridge 17 is realized.

The stopper 45 or the material used for the stopper 45 can include an indicator which changes its state when the stopper 45 is used or after a certain period of time. The indicator can be a dye, for example. That is, the plug 45 changes color with a single use. For example, plug 45 discolor on contact with air or moisture or the medium. For example, the plug 45 changes color after a certain time, for example eight hours.

the 17 and 18 show another embodiment of a plug 45. The plug 45 according to FIGS 17 and 18 is particularly suitable for low to medium-viscosity media. As previously mentioned, the plug 45 comprises two sealing lips 50, 51. In contrast to the plug 45 according to FIGS Figures 14 to 16 includes the plug 45 according to 17 and 18 three annular grooves 52, 53, one of which in the 18 only two are provided with a reference number. Facing the medium, the plug 45 comprises a conical section 66 which bulges out of the plug 45. When using the plug 46 according to FIGS 17 and 18 the stator 12 has a cone-shaped geometry corresponding to the cone section 66 of the plug 45, in particular a counter-cone section 67, as for example in FIG 13 is shown.

the 19 and 20 show a further embodiment of a plug 45. In contrast to the plug 45 explained above, the plug 45 according to FIG 19 and 20 only one sealing lip 51 facing the medium. Furthermore, no annular grooves 52, 53, as mentioned above, are provided on the rotor opening 46. The plug 45 according to 19 and 20 is particularly suitable for low to high viscosity media. However, the stopper 45 is particularly preferably suitable for highly viscous media. In this case, the rotor opening 46 is designed as a stepped bore.

the 21 and 22 show another embodiment of a plug 45. The plug 45 according to FIGS 21 and 22 is particularly suitable for low to high viscosity materials. The plug 45 according to 21 and 22 differs from the plug 45 according to the 19 and 20 characterized in that the rotor breakthrough 46 is designed such that the plug 45 only in the area thin-walled membrane 58 is in contact with the plug 45. The plug 45 comprises only one circumferential sealing lip 51 facing the medium. In this case, the plug 45 is preferably made of a particularly elastic material.

The eccentric screw pump 1 can be used in particular for additive or generative manufacturing. That is, the progressive cavity pump 1 is a 3D print head or can be referred to as such. 3D printing is a comprehensive term for all manufacturing processes in which material can be applied layer by layer to create three-dimensional objects. The layered structure is computer-controlled from one or more liquid or solid materials according to specified dimensions and shapes.

Physical or chemical hardening or melting processes take place during construction. Typical materials for 3D printing are plastics, synthetic resins, ceramics and metals. Meanwhile, carbon and graphite materials have also been developed for 3D printing carbon parts. Although it is a primary forming process, no special tools are required for a specific product that have stored the respective geometry of the workpiece, such as casting molds. 3D printers are used in industry, model making and research to produce models, samples, prototypes, tools, end products or the like. Furthermore, these are also used for private use. There are also applications in home and entertainment, construction, and art and medicine.

These processes are used in the parallel production of very small components in larger quantities, for unique items in jewelry or in medicine and dental technology, both in small series production and in individual production of parts with a high geometric complexity, also with additional function integration. In contrast to primary shaping, forming or subtractive manufacturing processes such as cutting, 3D printing becomes more economical as the complexity of the component geometry increases and the number of pieces required decreases. In recent years, the areas of application for these manufacturing processes have been expanded to other fields. 3D printers were initially used primarily for the production of prototypes and models, then for the production of tools and finally for finished parts, of which only small quantities are required.

A number of fundamental advantages over competing manufacturing processes are leading to an increasing spread of the technology, including in the series production of parts. Compared to the injection molding process, 3D printing has the advantage that the time-consuming production of molds and mold changes are no longer necessary. Compared to all material-removing processes, such as cutting, turning, drilling or the like, 3D printing has the advantage that there are no additional processing steps after the primary shaping. In most cases, the process is energetically cheaper, especially if the material is only built up once in the required size and mass. However, as with other automated processes, post-processing may be necessary depending on the area of application.

Further advantages are that different components can be manufactured on one machine and complicated geometries can be generated. Using the progressing cavity pump 1 for 3D printing is an extrusion-based process. Silicones, polyurethanes, ceramic and metal pastes, epoxy resins and acrylates, for example, can be processed with the aid of the eccentric screw pump 1 .

The advantages over other technologies that are able to print liquids are the applicability for high viscosities, the high precision and process stability, the wide range of materials that can be used and the high application speed. Other technologies are dependent on material adjustments, some of which are strong, in order to achieve a meaningful printing process. For example, light-based technologies for liquids always depend on the presence of a photon crosslinker, whereas the progressing cavity pump 1 can print completely independently of the curing mechanism.

In particular, the eccentric screw pump 1 can be used for so-called bioprinting. The field of application of bioprinting is still very young and represents the latest step in cell culture technology. It can be seen as a special form of additive manufacturing at the interface between medical technology and biotechnology. The topic of "bioprinting" is often introduced with words about the great need for donor organs. It is essential that tissue and organs are artificially produced in the future in order to meet the enormous demand. Realistically, this vision is still a long way off if it should ever become reality.

Nevertheless, the use of simpler tissue constructs is getting closer. For example, cartilage implants or simulated skin areas for faster wound care are conceivable. Bone wax and bone replacement materials are also possible. Individually manufactured bone implants made from body-compatible materials are already in use. However, this is not to be seen as bioprinting in the narrower sense, as no biological materials are used.

Great potential can be seen in the research field of "drug discovery". Here you can find out about side effects and interactions within a very short time different active ingredients can be obtained. For this purpose, "mini-organs" are printed, which can depict all the essential functions of a shelf organ. Using microfluidic techniques, these mini-organs can be combined into multi-organ systems and the systemic effects of active substances can thus be tested without the need for animal experiments.

In bioprinting, cell-loaded gels or matrices are produced for maintaining and cultivating the same with the aid of the eccentric screw pump 1, in particular with the aid of a bioprinter. This is done through a layered structure, which is known from additive manufacturing. Since most of the media used in bioprinting are loaded with living cells, which can only be produced with considerable expenditure of time and money, gentle application is essential. The stress on the deployed cells increases with the cell density and the viscosity of the medium. For meaningful constructs, however, the highest possible cell density and stability are required. This creates a tension between cell concentration and application technology.

The special feature of the eccentric screw pump 1 consists in the design of the cartridge system 16 as a disposable item. In this case, the cartridge system 16 containing the stator 12 is replaced after it has been used once. The drive device 2 itself remains. It is also necessary to replace the plug 45, which is part of the cartridge system 16. It is also possible to exchange the rotor 10 in the event that this is part of the cartridge system 16 .

Using the cartridge system 16 as a single-use printhead has many advantages over established methods. A high level of precision and resolution can be achieved during the application. Process fluctuations are compensated and enable consistent and reproducible printing results. Ambient parameters are leveled. It is a gentle product Delivery of low to high-viscosity media possible. There is no clogging of a dosing needle.

There is no compromise between cell-friendly application and precision. The application can be done without pulsation. Active withdrawal of medium into the cartridge system 16 is possible in order to prevent thread formation or dripping. The hygienic implementation or sterilization enables a contamination-free process. This is guaranteed by the one-time use. A low dead volume enables almost complete extrusion of the medium. Easy integration into existing bioprinters is possible. The design does not require a separate controller and is geometrically optimized for bioprinters. It is easy to handle without additional tools.

With the help of the plug 45, both the interior 19 of the cartridge 17 can be sealed off from the environment and the drive unit 3 can be protected against contamination with the medium. Because the medium is not supplied via a hose or pipeline, but is held directly in the cartridge system 16, the dead volume can be reduced since the medium is very expensive and even the smallest amounts are too valuable to use as dead volume to lose. Loss-free feeding and at least almost complete emptying of the cartridge system 16 are ensured.

Since the cartridge system 16 is a disposable item, it can be easily sterilized. Due to the fact that the cartridge system 16 can be replaced, the drive device 2 itself does not have to be cleaned. It is therefore not necessary to completely dismantle the drive device 2 in order to clean the eccentric screw pump 1 . The cartridge system 16 can be changed very easily and quickly are, whereby the eccentric screw pump 1 is ready for use again in a very short time.

Biological media are usually dosed within a working range of + 4 °C to + 40 °C, since most cells can only survive in a narrow temperature range. The media to be printed are very often subject to a temperature-controlled gelation mechanism that ensures dimensional stability during printing. This requires precise temperature control. Refrigeration is also important so that some cell types do not die and certain gels can be printed.

The medium can be sealed off from the interior space 19 with the aid of the eccentrically sealing plug 46 . This leads to freedom from contamination and ensures that sensitive components, for example the drive unit 3, are protected. The plug 45 serves not only for sealing, but also fulfills the function of power transmission to the medium in order to supply a preliminary pressure for the metering of the same. This form can be applied, for example, by compressed air supplied via the air supply 14 or by a spring.

the 23 12 schematically shows a filling concept for filling the cartridge system 16. First, the plug 45 is pushed into the cartridge 17. FIG. The membrane 58 of the plug 45 faces the stator 12 . The plug 45 is pushed into the cartridge 17 until the plug 45 is in contact with the stator 12 .

A syringe 68 filled with a medium M is then connected to the Luer lock connection 18 of the cartridge 17 via an adapter 69 . The cartridge system 16 is now filled with the medium M, with the plug 45 moving away from the stator 12 . Once the cartridge system 16 with the Medium M is filled, the cartridge system 16 is connected to the drive device 2 . Here, the membrane 58 is pierced by the rotor 10 . Furthermore, a nozzle 70 is attached to the Luer lock connection 18 . The cartridge system 16 is connected to the drive device 2 with the aid of the bayonet lock 27 . The dosing of the medium M can now be started.

To fill the cartridge 17 and to protect the medium M from the environment, it is necessary for the plug 45 to be closed. This is solved in that the stopper 45 is provided with the perforable membrane 58 in the middle. After the cartridge system 16 has been filled, this should still be tight when the rotor 10 pierces the membrane 58 from above. Furthermore, the plug 45 must allow the eccentric movement of the rotor 10 while the cartridge system 16 is being completely emptied and still remain sealed. This is achieved by an appropriate choice of material for the plug 45.

In order to largely eliminate dead space, it is necessary for the medium M to be able to remain in as few indentations, cavities or undercuts as possible. A product-contacting inner geometry of the cartridge 17 that is as simple as possible is therefore well suited. Therefore, the cartridge 17 is also cylindrical on the inside. The potential disadvantage that the rotor 10 has to be guided through the center of the cartridge 17 and that medium M can potentially stick to the rotor unit 8 is compensated for by the wiping function of the plug 45 . An optimal emptying of residues is achieved by a conically tapering stator 12 and a correspondingly shaped plug 45, as is also the case, for example, in FIGS 13 and 18 is shown.

It is difficult to completely clean and sterilize an eccentric screw pump, taking into account the feasibility in everyday laboratory work. However, this problem can be solved by the introduction of the cartridge system 16 to be fixed as a one-time item. The one-time use of the pump parts that are essential for dosing guarantees absolute security in terms of sterility and freedom from contamination. All parts that come into contact with the product can be replaced after a single use, that is to say after the cartridge system 16 has been emptied once. Both the stator 12, which is firmly connected to the cartridge 17, and the rotor 10 and the plug 45 can be exchanged.

To ensure single use, the following measures can be taken. The rotor-stator combination can be designed for a small dosing volume up to failure. The stopper 45 can be irreversibly destroyed after a single use, for example by puncturing the membrane 58. It is possible for the rotor 10 to snap into the cartridge 17 so that it cannot be separated from the cartridge system 16. An irreversible closure of the cartridge 17 is possible, so that the damaged stopper 45 cannot be replaced. Furthermore, a color indication is possible, which indicates a single use.

The handling of the cartridge system 16 is simplified to such an extent that a user only has to fill the cartridge system 16 , insert the rotor unit 8 into the drive device 2 and tighten the cartridge system 16 on the drive device 2 . Dismantling and assembly are possible without tools. The cartridge system 16 can be filled, operated and exchanged in a sterile manner without leaving any residue. After use, the rotor 10, in particular the rotor unit 8, is automatically removed from the drive device 2 when the cartridge system 16 is pulled off. The handling is therefore largely the same as that of a regular cartridge. The extrusion is controlled via stepper motor signals from a controller. No separate control is required, which improves handling in practice.

In order to be able to use the progressing cavity pump 1 in existing 3D printers, a reduction in weight and size is desirable. The greatest savings are possible by selecting a suitable drive unit 3. Since the sealing of the drive unit 3 does not have to withstand high pressures, it can also be made smaller. The materials for the drive device 2 are chosen so that they are as light as possible. The housing 4 can be partially made of metal or plastic. Since the components rotor 10, stator 12, plug 45 and cartridge 17 are made of plastic, the weight is further reduced.

The temperature of the medium M can be regulated via an external element that can be plugged onto the cartridge system 16 . The cooling or heating takes place directly on an outer surface of the cartridge 17 and can be kept constant over the entire length of the cartridge 17 by means of an adapted shape. There is no thermal bridge between the drive unit 3 and the cartridge system 17, as a result of which the increase in engine temperature does not have a direct effect on the contents of the cartridge. This is implemented on the one hand by the relatively large distance between the drive unit 3 and the cartridge system 16, on the other hand by a suitable choice of materials. Plastic prevents the conduction from the drive unit 3 to the medium M. Metal provided on the drive unit 3 promotes heat dissipation to the environment.

In addition to the use of the eccentric screw pump 1 in the field of bioprinting, other areas of application are also conceivable. In additive manufacturing, the use of the progressing cavity pump 1 does not have to be limited to bioprinting. Materials such as silicones, epoxy resins, polyurethanes, ceramic, metal and solder pastes can also be printed. With a compact design, it is also conceivable to open up the market for amateur 3D printers.

Another possible application is the printing of meat substitute products. Strict hygienic regulations also apply here. Many different materials are used and the viscosity can be very high. It is irrelevant whether the substitute products were generated directly from animal sources or are reproduced or replaced by plant sources.

Use in the chemical industry is also possible. Some chemicals are generally not suitable for printing with progressive cavity pumps due to their tendency to stick. For example, cyanoacrylates pose a problem because they can cure in the presence of moisture and completely destroy the progressive cavity pump. A closed system in the form of the cartridge system 16 explained above, which can be quickly replaced in the event of a malfunction without major damage, is advantageous.

The use of the cartridge system 16 also makes sense in a laboratory environment in which small quantities are tested and rapid product changes take place. If, for example, different formulations of an adhesive compound are tested, the entire eccentric screw pump would always have to be dismantled and cleaned in the case of an eccentric screw pump without such a cartridge system 16 . Since there are no sterility requirements for adhesives, it would also be conceivable to only change the cartridge 17 and not the rotor unit 8 . Different cartridge sizes ensure usability in different areas.

In medical technology, among other things, use as a hand applicator would be conceivable. The cartridge system 16 can be used for the precise application of material in wound care, in the body, in operations, in dental treatments or for dispensing medication. One The interface between additive manufacturing and medical technology is, for example, the printing of tablets. Problems with interactions, overdosing and underdosing as well as forgetting to take a tablet can be counteracted by individually creating tablets with patient-specific active ingredients and active ingredient contents. The eccentric screw pump 1 can also be used for printing tablets.

the 24 shows a schematic sectional view of a further embodiment of an eccentric screw pump 1. The 25 shows the detailed view C according to FIG 24 . The eccentric screw pump 1 according to the 24 differs from the eccentric screw pump 1 according to the 1 and 2 only in that the cartridge system 16 has a spring element 71 which is arranged between the plug 45 and the bearing housing 5 . Ring-shaped pressure pieces 72, 73 are provided on both sides of the spring element 71. In addition, pressurization via the air supply 14 is also possible. The interior 19 of the cartridge 17 can also be subjected to a negative pressure, in particular a vacuum.

In contrast to the eccentric screw pump 1 according to the 1 and 2 this task is taken over by the spring element 71 instead of pressurizing the plug 45 with air. The spring element 71 has a linear characteristic. The exertion of force on the plug 45 can take place on the one hand via air pressure, with the aid of a spring force of the spring element 71 or with the aid of a spindle drive (not shown). In the latter case, an eccentric insert in the plug 45 is provided. The pitch of this eccentric insert is adapted to the volumetric quantity and therefore also to the stopper speed. That is, the plug 45 is positively guided.

As the 25 1, a slide bushing 74 for supporting the drive shaft 7 in the bearing housing 5 is provided. The slide bushing 74 includes a first sealing ring 75 and a second sealing ring 76. It is also possible for only one sealing ring 75, 76 to be provided. The sealing ring 75 seals against a vacuum in the interior space 19 .

the 26 shows a schematic sectional view of a further embodiment of a cartridge system 16. The 27 shows the detailed view D according to FIG 26 . In this further development of the cartridge system 16 , latching hooks or snap hooks 77 , 78 are provided on the inside of the cartridge 17 . Furthermore, a cover 79 closing the cartridge 47 is provided. The cover 79 can be plate-shaped and includes a central opening 80 through which the rotor unit 8 is passed. The cover 79 includes a peripheral engagement section 81 which engages behind the latching hooks 77 , 78 . That is, the cover 79 can, as in the 27 indicated by arrows, are pressed into the cartridge 17, the engagement section 81 snapping in behind the snap hooks 77, 78. The cover 79 can no longer be separated from the cartridge 17.

Latch hooks or snap hooks 82, 83 can be provided on the rotor unit 8, in particular on the flexible shaft 9. The number of snap hooks 82, 83 is arbitrary. The snap hooks 82, 83 can engage behind the cover 79. In particular, the snap hooks 82, 83 protrude radially further out of the rotor unit 8 than the diameter of the opening 80 is large. The rotor unit 8 can be guided through the opening 80 . As soon as the snap hooks 82, 83 have passed through the opening 80, they engage behind the cover 79. Now the rotor unit 8 can no longer be separated from the cartridge system 16 either.

That is, the cartridge system 16 and all components of the cartridge system 16 can actually only be used once. Alternatively, however, the rotor unit 8 and the plug 45 could also be cleaned and repeatedly be reused. However, the cover 79 can at least ensure that the cartridge 17 is only used once. The advantage here can be seen in single use or contamination, for example in the case of toxic or carcinogenic active substances, as well as in cleaning and self-protection.

the 28 shows a schematic sectional view of a further embodiment of a cartridge system 16. The cartridge system 16 according to FIG 28 is fully encapsulated. A cover 84 is provided on the back of the cartridge 17 for this purpose. The cover 84 is glued or fused to the cartridge 17, for example. The cover 84 is connected to the cartridge 17 in a fluid-tight manner.

The cartridge system 16 is thus completely encapsulated and, in addition to the cartridge 17, includes the stator 12, the rotor unit 8 and the plug 45 (not shown). The interface 32 of the rotor unit 8, in particular the flex shaft 9, is designed as a non-contact interface. In particular, the interface 32 is provided on the flexible shaft 9 . Accordingly, a corresponding counterpart interface is provided on the drive device 2 . The interface 32 can be a magnetic coupling or part of a magnetic coupling, for example.

In principle, all embodiments of the cartridge system 16 or the cartridge 17 can have an RFID chip (Radio Frequency Identification). In this way, in particular, a geometry of the stator 12 can be recognized in order, for example, to be able to assign the appropriate rotor 10 to the stator 12 . It is thus possible, for example, to identify a size. Furthermore, batch recognition of the medium M contained in the cartridge 17 is also possible.

The cartridge system 16 or the cartridge 17 can also have a QR code (English: Quick Response), which is lasered into the cartridge 17, for example. With this, for example, the medium M accommodated in the cartridge 17 can be identified. Information can then be read out, for example, which allows conclusions to be drawn about the contents of the cartridge 17, namely the medium M. For example, a batch recognition, a statement about the service life or the durability of the medium M, a product tracking or the like is possible.

The eccentric screw pump 1 can be mains operated or battery operated. This means that battery operation of the drive unit 3 is possible. As a result, the eccentric screw pump 1 is independent of a power grid. The eccentric screw pump 1 can thus work independently as a handheld device. For example, the eccentric screw pump 1 can be used to meter soldering paste at a manual workstation. The eccentric screw pump 1 can thus be used in the manner of a pipetting device or pipetting aid, with the difference that the eccentric screw pump 1 can also be used to dose highly viscous media M. Furthermore, such a self-sufficiently working eccentric screw pump 1 can also be used to treat quick wounds, for example for field treatment by emergency services, in doctors' surgeries or in the operating room. In this case, for example, waxes, in particular bone waxes, adhesives, medicines, denture materials, artificial skin or the like can be dosed.

Although the present invention has been described using exemplary embodiments, it can be modified in many ways.

REFERENCE LIST

1

progressing cavity pump

2

drive device

3

drive unit

4

Housing

5

bearing housing

6

fastener

7

drive shaft

8th

rotor unit

9

flex shaft

10

rotor

11

Top

12

stator

13

breakthrough

14

air supply

15

air duct

16

cartridge system

17

cartridge

18

Luer lock connector

19

inner space

20

arm section

21

arm section

22

engagement section

23

counter engagement section

24

breakthrough

25

ring groove

26

o ring

27

bayonet lock

28

recess

29

recess

30

face

31

face

32

interface

33

wrench flat

34

arm section

35

arm section

36

arm section

37

arm section

38

slot

39

slot

40

detent

41

counter interface

42

wrench flat

43

wrench flat

44

Unit volume

45

Plug

46

rotor breakthrough

47

inner part

48

outer part

49

axis of symmetry

50

sealing lip

51

sealing lip

52

ring groove

53

ring groove

54

labyrinth seal

55

stiffening ring

56

fillet

57

pressure ring

58

membrane

59

membrane section

60

membrane section

61

membrane section

62

membrane section

63

perforation

64

perforation section

65

perforation section

66

cone section

67

counter-cone section

68

Injection

69

adapter

70

jet

71

spring element

72

Pressure piece

73

Pressure piece

74

sliding bush

75

sealing element

76

sealing element

77

snap hook

78

snap hook

79

lid

80

breakthrough

81

engagement section

82

snap hook

83

snap hook

84

lid

A

detail view

B

detail view

C

detail view

D

detail view

L

longitudinal direction

M

medium

Claims (20)

Cartridge system (16) for an eccentric screw pump (1), with
a cartridge (17) for receiving a medium (M) to be dosed,
a stator (12) which is provided on the cartridge (17) and which interacts with a rotor unit (8) of the eccentric screw pump (1) to meter the medium (M), and
a plug (45) movably mounted in the cartridge (17) for fluid-tight sealing of the cartridge (17), the plug (45) comprising a rotor opening (46) through which the rotor unit (8) can be passed. Cartridge system according to Claim 1, in which the stator (12) and the cartridge (17) are formed in one piece, in particular in one piece of material, or in which the stator (12) and the cartridge (17) are connected to one another in a positive, non-positive and/or cohesive manner. Cartridge system according to Claim 1 or 2, in which the rotor opening (46) is closed with the aid of a membrane (58) facing the stator (12). Cartridge system according to Claim 3, in which the membrane (58) comprises a perforation (63), the perforation (63) preferably dividing the membrane (58) into a plurality of membrane sections (59-62). Cartridge system according to Claim 3 or 4, in which the plug (45) comprises a pressure ring (57) through which the rotor opening (46) is guided and on which the membrane (58) is provided. Cartridge system according to Claim 5, in which the stopper (45) comprises a stiffening ring (55) facing away from the pressure ring (57) and through which the rotor opening (46) is guided. Cartridge system according to one of Claims 1 - 6, in which at least one circumferential annular groove (52, 53) is provided on the rotor opening (46). Cartridge system according to one of claims 1 - 7, wherein the plug (45) facing away from the stator (12) comprises a circumferential first sealing lip (50) which rests on the inside of the cartridge (17), and / or wherein the plug (45) dem Stator (12) facing a circumferential second sealing lip (51) which also bears on the inside of the cartridge (17). Cartridge system according to Claim 8, in which the second sealing lip (51) has a greater rigidity than the first sealing lip (50). Cartridge system according to Claim 8 or 9, in which the first sealing lip (50) extends further out of the stopper (45) at the end face than the second sealing lip (51). Cartridge system according to one of Claims 1 - 10, further comprising the rotor unit (8), which is passed through the rotor opening (46). Cartridge system according to Claim 11, in which the rotor unit (8) is permanently connected to the cartridge (17) and/or the plug (45). A cartridge system according to claim 11 or 12, wherein the rotor unit (8) is completely encapsulated by the cartridge (17). Cartridge system according to one of claims 11 - 13, wherein the rotor unit (8) comprises an interface (32) for coupling the rotor unit (8) to a counter-interface (41) of a drive device (2) of the eccentric screw pump (1). Cartridge system according to Claim 14, in which the interface (32) comprises a latching lug (40) which latches into the counter-interface (41) when the rotor unit (8) is connected to the drive device (2). Cartridge system according to Claim 15, in which the interface (32) comprises a plurality of elastically deformable arm sections (34 - 37) on which the latching lug (40) is provided. Cartridge system according to one of Claims 1 - 16, further comprising the medium (M) accommodated in the cartridge (17). A cartridge system according to any one of claims 1-17, wherein the plug (45) comprises an indicator which changes state after use of the cartridge system (16). Cartridge system according to one of claims 1 - 18, wherein the plug (45) is made of an air-permeable or air-impermeable material. Eccentric screw pump (1), in particular 3D print head, with a drive device (2) and an exchangeable cartridge system (17) according to one of Claims 1 - 19, which is detachably connected to the drive device (2).

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