WO2019091701A1

WO2019091701A1 - Stator assembly for an eccentric screw pump

Info

Publication number: WO2019091701A1
Application number: PCT/EP2018/077931
Authority: WO
Inventors: Sascha Plazar; Johannes Schulz
Original assignee: Seepex Gmbh
Priority date: 2017-11-07
Filing date: 2018-10-12
Publication date: 2019-05-16
Also published as: DE102017126002B3

Abstract

The invention relates to a stator assembly for an eccentric screw pump, comprising at least: a stator (1) made of an elastic material; and a stator housing (3) surrounding at least regions of the stator (1) in the circumferential direction and extending along the longitudinal direction, as well as consisting of at least two housing segments (12) and forming a stator clamping device with which the stator can be adjusted; characterised in that the housing segments (12) are provided with one or more respective clamping elements (14) between the end faces, and in that the housing segments (12) are connected to one another via one or more clamping profiles (13) extending along the longitudinal direction (L), wherein the clamping profiles (13) are each provided with one or more counter elements (16) which interlockingly cooperate with the clamping elements (14) in such a way that the housing segments (12) are adjusted in the radial direction in the course of a longitudinal shifting of the clamping profile (13).

Description

STATOR COMPONENT FOR AN ECCENTRIC SCISSOR PUMP

Description:

The invention relates to a stator assembly for an eccentric screw pump having at least one stator of elastic material, a stator circumferentially surrounding the stator at least partially and extending along the longitudinal direction stator shell, which consists of at least two shell segments and forms a Statorspannvorrichtung, with the stator deliverable bar , z. B. (in the radial direction) can be tensioned against the rotor.

Moreover, the invention relates to an eccentric screw pump with such a stator and a rotor. In such an eccentric screw pump, the rotor z. B. connected via at least one coupling rod to the drive or a drive shaft, wherein the coupling rod is also referred to as a propeller shaft. The coupling rod can z. B. be connected via a first joint to the rotor and a second joint with the drive shaft or connected to the drive connecting shaft. The stator is z. B. with its one end to the pump housing or a corresponding flange of the pump housing and connected with its other end to the terminal housing or a corresponding flange of this terminal housing. The pump housing is also referred to as a suction housing and the connection housing is z. B. also referred to as a connecting piece. In this case, the stator made of elastic material, for. B. made of an elastomer. It can be z. B. be a synthetic rubber or natural rubber or a rubber mixture.

Preferably, the stator is a longitudinally divided stator of at least two Statorteilschalen, z. B. stator half shells formed. However, the invention also includes embodiments with a one-piece stator. The stator jacket is z. B. made of metal and preferably in several parts, for. B. as a longitudinally divided shell composed of several (separate) shell segments. In any case, the stator jacket forms a stator clamping device, with which the stator can be tensioned in the radial direction against the rotor. Such an eccentric screw pump with Statorspannvorrichtung is z. B. from DE 10 2008 021 920 A1. The clamping takes place directly over clamping screws, which work in the radial direction on the end attachment flanges of the shroud segments. The extent known eccentric screw pump has proven excellent in practice, since not only a simple replacement of the rotor without costly disassembly of the pump is possible, but because the stator can be reliably delivered and retighten in a simple manner.

On this basis, it is proposed in such an eccentric screw pump with longitudinally split casing in DE 10 2014 1 12 550 B4 that the casing segments have at least one clamping flange with wedge-shaped clamping surfaces at the ends and clamping elements which are displaceable on the clamping flanges in the axial direction are placed with second wedge-shaped clamping surfaces , so that the stator jacket in the course of an axial displacement of the clamping elements in the radial direction against the stator can be tensioned. The axial displacement of the clamping elements can with adjusting elements, for. B. set screws, but must be absorbed primarily in the course of tensioning and consequently adjusting forces. During operation, however, then only reduced forces of these control elements

received, because for the most part, the forces are directly or indirectly absorbed by the axially displaceable clamping elements (in particular clamping rings). Incidentally, DE 102 41 753 C1 discloses a stator for an eccentric screw pump which is provided with an outer jacket which consists of a plurality of segments extending in the axial direction and connected to one another, the longitudinal edges of the segments being designed such that adjacent ones Intermesh segments and produce a load on train positive connection. The surfaces of the segments lie predominantly in one plane, so that the result of the connection of several segments to form a closed shell is a polygonal shape. The outside of the elastic stator itself also has a polygonal shape, so that there is a positive connection between the elastic stator and the interconnected shell segments.

Similarly, DE 10 2006 021 897 B4 describes a stator shell for progressing cavity pumps, which is formed polygonformig, wherein in individual polygonal surfaces at least one groove is introduced, which is to reduce an adhesive effect between the elastomeric stator and the stator jacket. The stator shell is formed as a slotted stator having a longitudinally extending through slot, which slot may be covered by a closure strip extending along the longitudinal axis of the stator shell.

Based on this, DE 10 2012 008 761 B4 describes in DE 10 2012 a stator arrangement for an eccentric screw pump with a stator casing on the one hand and an elastomeric stator or stator insert on the other hand, the stator casing having cavities, recesses and / or elevations open on the front side.

has and preferably as profile body, z. B. chamber profile body is formed. The stator jacket can be formed as a longitudinally divided stator jacket made of at least two partial shells, which are detachably connected to one another and which are connected to one another by means of a positive connection and on the other hand by means of a closure unit.

Although the last-described stator arrangements make it possible to replace a stator or stator insert, variable delivery or clamping and in particular retightening is not possible.

In practice, however, there is a need to provide stator arrangements which enable in a simple manner a reliable infeeding / tensioning and, in particular, retensioning of the stator in order to be able to optimally adapt the stator to the respective conditions, in particular also at high operating pressure. - This is where the invention starts.

The invention has for its object to provide a stator for an eccentric screw pump of the type described above, which allows for simplified assembly and optimized clamping and delivery of the stator.

To solve this problem, the invention teaches in a generic Statoraggregat of the type described above, that the shell segments between the front ends on or on its outside (in the region of their longitudinal sides), each provided with one or more clamping elements,

that the shell segments over one or more along the longitudinal direction extending clamping profiles, the z. B. are formed as strip-shaped clamping profiles or clamping strips are connected to each other, wherein the clamping profiles are each provided with one or more counter-elements, which cooperate with the clamping elements such a form-fitting manner that the shell segments are delivered in the course of a longitudinal displacement of the clamping profile. This means that the shell segments are tensioned in the tangential direction and / or in the radial direction (that is to say in the direction of the rotor which can be mounted inside the stator).

The invention is based on the recognition that the delivery (in the radial direction) and consequently the tensioning of the elastomeric stator can be optimized if the infeed or tension is not (exclusively) via flanges connected to the shell segments at the end, but if the tensioning or infeed tensioning profiles (eg tensioning strips or clamping strips) are made available, which extend along the longitudinal direction of the stator and with which a tensioning of the individual shell segments can take place over the length of the shell segments. Because in the course of a displacement of the clamping profiles along the longitudinal direction arranged on the shell segments clamping elements on the one hand and arranged on the clamping elements counter elements on the other hand form-fit together so that in the course of a longitudinal displacement of the clamping profile, the shell segments delivered in the tangential and / or radial direction and consequently braced become. This can be z. B. realize that are arranged as clamping elements on the shell segments one or more clamping projections which protrude as elevations of the segment surface. Accordingly, one or more clamping recesses (for example recesses or recesses) can be used as counterelements on or in the clamping profiles

Openings) may be provided, so that the clamping projections of the sheath segments engage in the clamping recesses of the clamping profiles or clamping strips. But it is also possible conversely that the shroud segments recesses and the clamping profiles have projections.

Incidentally, for the displacement of the clamping profiles in the longitudinal direction (relative to the shell segments) preferably provided adjusting elements, the z. B. can be configured as screws or the like. Take such screws through z. B. openings in the end attachment flanges of the shell segments. Because the shroud segments each preferably have shroud portions extending along the longitudinal direction and circumferentially abut against the stator and the end of this shell sections of the shroud segments then the mounting flanges are connected, which serve to attach the shell to the other pump components, in particular pump housing and connector housing.

In one embodiment, it is provided that the clamping elements have one or more wedge surfaces, for. B. wedge-shaped in some areas and / or if the clamping recesses have wedge surfaces, for. B. at least partially wedge-shaped. By this wedge-shaped configuration or the wedge surfaces, a deflection of the displacement in the longitudinal direction is then deflected in a tangentially aligned feed movement in the region of the clamping profiles, which then in turn causes a delivery of the stator jacket in the radial direction. This makes it possible to evenly clamp or deliver the elastic stator arranged in the interior of the stator jacket over the length, because the forces for the feed movement are not (only) on

the ends introduced into the shell segments, but distributed over the longitudinal direction of the stator segments.

Each counter element (eg each clamping recess) acts together with two clamping elements (eg clamping projections) of two side-by-side arranged jacket segments, so that z. B. via a clamping recess, the two arranged on different shell segments projections are contracted in the course of the tension.

There is the possibility that all clamping projections have wedge surfaces and that also the clamping recesses have wedge surfaces on both sides, so that each wedge-shaped clamping projection cooperates with a corresponding wedge surface.

In an alternative embodiment, there is the possibility that in a clamping recess not two wedge-shaped clamping projections, but only a wedge-shaped clamping projection and a non-wedge-shaped clamping projection, for. B. engage a straight, web-shaped clamping projection. This can be z. B. realize that a shell segment is equipped with wedge-shaped clamping projections and that adjacent shell segment is formed with web-shaped, straight clamping projections. The clamping recesses can then be (likewise) asymmetrical and have a wedge surface only at one edge and a straight surface at the other edge.

Incidentally, it is within the scope of the invention that all over the length of a shell segment distributed clamping projections are dimensioned identically and in the case of wedge-shaped clamping projections z. B. the same wedge angle

or have the same slope. Alternatively, however, it is also within the scope of the invention that the plurality of clamping projections arranged one behind the other are dimensioned differently and z. B. have wedge surfaces with different pitch. In addition, there is the possibility that the wedge surfaces of the clamping recesses of the clamping strips are dimensioned differently. Such a different dimensioning over the length of the clamping bar and / or over the length of the shroud segments, it is possible to realize a variable tension over the length of the shroud segments in the course of the displacement of the clamping bar, so that z. B. from the suction side to the pressure side an increasing tension can be realized or vice versa.

In an alternative embodiment, the clamping projections (on the shell segments) are not wedge-shaped or web-shaped, but as a pin and consequently pin-shaped, preferably round pins are provided. These round pins on the shell segments can then interact in turn with wedge-shaped or at least partially wedge-shaped clamping recesses on the clamping bars. Consequently, a tension with non-wedge-shaped clamping projections can also be realized via wedge-shaped clamping recesses. The peg-shaped and preferably round clamping projections have the advantage that friction forces can be reduced in the course of the tension. This effect can be further optimized by the fact that the cone-shaped clamping projections or clamping pins are rotatably attached to the shell segments, z. B. ball-bearing or sliding. It is also within the scope of the invention that the pin-shaped clamping projections are provided with a rotatable ring, so that the ring can rotate about the pin in the course of the tension. Always it is expedient if these pin-shaped projections cooperate with corresponding wedge surfaces of the tension.

The clamping profiles (eg clamping strips) may preferably be formed in one piece and z. B. be provided with one or more clamping recesses. Alternatively, however, it is also within the scope of the invention that the clamping profiles are composed of a plurality of longitudinally successively arranged profile segments, which are preferably releasably connected to each other. Thus, it is possible to provide a separate profile segment for each clamping recess available, so that about rod-shaped connections, for. B. threaded rods several such profile segments can be connected to each other to form a clamping profile. In this way, the clamping bar can be variably assembled and adjusted.

It is provided in one embodiment that the shell segments a plurality of distributed along the longitudinal direction and spaced apart clamping elements, for. B. clamping projections and / or that the clamping profiles distributed more along the longitudinal direction and spaced from each other (corresponding) counter elements, for. B. have clamping recesses. Thus, it is expedient if at least three, preferably at least four longitudinally distributed clamping elements and / or counter elements are provided.

In a modified embodiment, however, there is also the possibility that the clamping profiles each have only a single clamping recess, which then, however, over a substantial part of the length of the clamping profile or the shell segments, z. B. extends over at least 50% of the length of the shell segments. The configuration of such a single clamping recess can be realized in the same way as described in connection with the plurality of clamping recesses. It is

then advantageous if the shroud segments each also have only a single clamping projection for each clamping profile, said clamping projections then also extend over a substantial part of the length of the shroud segments, z. B. over at least 50% of the length of the shell segments. Even with such an embodiment with only one over the length arranged clamping projection or a clamping recess, the tension can be optimized and in particular realize a uniform or deliberately uneven tension over the length, without providing over the length of a plurality of clamping projections and / or clamping recesses have to be. As a rule, in such an embodiment with only one clamping recess or one clamping projection, wedge surfaces with a smaller pitch will be realized than in embodiments with a plurality of clamping recesses or clamping projections. In an embodiment with a large pitch (for example with a plurality of clamping projections and / or clamping recesses), a relatively large travel distance in the tangential / radial direction can be achieved with a relatively small travel in the axial direction. In the case of wedge surfaces with a small pitch (for example, with only one clamping recess and / or one clamping projection), a relatively small travel in the axial direction can be achieved in the radial direction in a tangential direction, so that such a variant is particularly advantageous offers fine delivery.

It is fundamentally within the scope of the invention that the stator jacket is formed integrally longitudinally slit, so that it is formed by two firmly interconnected shell segments, which thus form the halves of a one-piece spreadable shell. The two longitudinal ends of this stator jacket are oriented with the interposition of a longitudinal gap against each other and with a (single) clamping profile against each other in tangential

Direction braced, so that the stator shell is stretched in total in the radial direction against the elastic stator or against the rotor disposed inside. The (elastic) stator can be formed in one piece or even in several parts.

Particularly preferably, however, the invention relates to embodiments in which the stator jacket is not integrally longitudinally slit, but is formed in several parts longitudinally divided and composed of several separate shell segments whose longitudinal ends are oriented in pairs with an intermediate circuit of a longitudinal gap against each other and each with a clamping profile against each other in tangential Direction be braced so that the stator shell is stretched in total in the radial direction against the elastic stator or against the rotor disposed therein. In such an embodiment with a "longitudinally split" stator jacket, therefore, a plurality of jacket segments are distributed over the circumference, with each individual jacket segment extending, for example, over the entire length of the stator jacket.

Likewise, it is alternatively possible to provide a stator jacket which has two or more shroud segments over the length of the stator, which are arranged one behind the other, based on the length of the stator or stator sheath, these individual shroud segments being distributed along the length by the clamping profiles according to the invention held together and stretched against each other. In this way, for example, a multi-stage stator assembly modular, so that even with stator units with a larger diameter, the individual jacket segments of the stator can still be easily moved and mounted. This has the advantage, in particular in the case of large-diameter stator units, that manual assembly can be carried out without the use of

Cranes, hoists or the like is possible. Such a structure of a plurality of successively arranged shroud segments is particularly possible because, according to the invention with the clamping profiles a tension of the stator over the length and not only at the ends. It goes without saying that this variant can be combined with distributed over the length of several shell segments with the variant in which a plurality of shell segments are distributed over the circumference, so that in a possible variant on the one hand over the circumference several shell segments are distributed, However, in turn, each of these individual jacket segments is also divided over the length considered in several segments.

The invention comprises in particular in the described longitudinally slotted variant of the stator shell embodiments in which the stator or stator are firmly connected to the shell segments, z. B. are vulcanized into the stator jacket.

However, the invention particularly preferably relates to embodiments in which the stator is arranged non-destructively or damage-free releasably in the stator shell and consequently is not materially connected to the stator jacket, so that the stator jacket on the one hand and the elastic stator on the other hand as separate parts replaceable available stand.

Incidentally, it is expedient if the (elastic) stator is formed or equipped on the outer peripheral side with one or more anti-rotation devices. Such a rotation can z. B. be realized in that the stator is equipped on the outer peripheral side with one or more webs which extend along the longitudinal direction of the stator shell. Such webs can be integrally formed on the stator, z. B. vulcanized

be and z. B. engage in the intermediate spaces or longitudinal gaps between the shell segments, so that the longitudinal webs are clamped as it were between two adjacent shell segments and thus form a rotation.

Alternatively, however, it is also possible to realize the rotation in another way, for. B. by the outer peripheral surface of the elastic stator has recesses or formations, which engage in corresponding recesses or formations on the inside of the stator shell. Alternatively or additionally, it is also possible to design the outer peripheral side of the stator and / or the stator casing to be polygonal on the inner peripheral side, in order to realize an anti-twist device in this respect.

The stator assembly according to the invention can be realized in a basically known manner for stators, which are integrally formed over the length. Optionally, however, it is also possible to arrange two or more elastic stators behind one another within the stator jacket.

The stator assembly according to the invention is characterized, inter alia, by a simple and easy construction of the stator shell, because the shroud segments can be made relatively light and slim with little material use, since the delivery not only distributed over the end flanges, but distributed over the length in the segments becomes. In addition, a symmetrical and thus optimized delivery over the entire length of the stator is made possible in particular. An eccentric screw pump with the stator assembly according to the invention can be operated at high pressures.

The invention is also an eccentric screw pump with a stator of the type described above, wherein the stator comprises the elastic stator and the stator jacket and the clamping profiles, which can also be regarded as part of the stator shell. Furthermore, the object of such an eccentric screw pump is a rotor which is rotatable in the stator. In principle, such an eccentric screw pump can furthermore have a drive, a coupling rod, a pump housing (eg suction housing) and / or a connection housing (eg a connecting piece). The basic structure of such an eccentric screw pump is known from the prior art and can be used within the scope of the invention.

In the following the invention will be explained in more detail with reference to a drawing showing only one exemplary embodiment. Show it:

1 shows an eccentric screw pump according to the invention in a simplified side view,

Fig. 2 shows a detail of a simplified vertical section through the

Pump according to FIG. 1

Fig. 3a shell segments of a first embodiment of the invention

Fig. 3b, a clamping profile for the shroud segments of Fig. 3a

3c shows the stator casing according to FIG. 3a with the clamping profiles according to FIG. 3b in the assembled state.

4a shows a modified embodiment of the figures 3a to 3c,

to 4c

Fig. 5a shows another embodiment of the invention

to 5c

6a shows a further embodiment of the invention

to 6c

Fig. 7a

to 7c, a further embodiment of the invention

8a, 8b, a modified embodiment of the invention.

In Figures 1 and 2, an eccentric screw pump is shown, which has in its basic structure a stator 1 made of an elastic material and a rotatable rotor 1 in the stator 2, wherein the stator is at least partially surrounded by a stator shell 3. The pump has a pump housing 4, which is formed in the embodiment as a suction housing, and a connection housing 5, which is also referred to as a discharge nozzle. Furthermore, the pump has a drive 6, which is connected via a connecting shaft or drive shaft 7 and a coupling rod 8 to the rotor 2. The coupling rod is connected in the embodiment via joints 9 on the one hand to the rotor 2 and on the other hand to the connecting shaft 7, wherein these joints 9 are formed so as to allow the eccentric movement of the rotor and the terminal end of the rotor. The suction housing 4 has a connection flange 10 and the connection housing 5 has a connection flange 11, wherein the stator 1 is arranged between these connection flanges 10, 11 and fixed in the axial direction. These connection flanges 10, 1 1 can be an integral part of

respective housing 4, 5 or be formed by separate adapter pieces.

The stator 1 is preferably designed as a longitudinally divided stator and for this purpose it consists of two merely indicated Statorhalbschalen 1 a, 1 b. Longitudinal means, along the stator longitudinal axis or parallel to this.

The stator shell 3 is also formed as a longitudinally divided shell and it has a plurality of shell segments 12, which serve as clamping segments and form a Statorspannvorrichtung, that is about these shell segments 12 can be the elastic stator 1 against the rotor and thus tension in the radial direction. However, in the context of the invention, the tensioning or delivery of the stator jacket 3 does not take place via the end attachment flanges of the shell segments, as is the case in the prior art, but with the aid of (separate) tensioning profiles 13, which are designed as tensioning strips. Reference is made, by way of example, to a comparative consideration of FIGS. 3a to 3c, which show a first embodiment of the invention. 3a shows the jacket segments 12 of the stator jacket 3. The stator jacket 3 can be composed of two or more such jacket segments 12 which are distributed over the circumference. In the illustrated embodiments, four shroud segments 12 are provided. It can be seen in FIG. 3a that the shroud segments 12 each have a plurality of clamping elements 14 on or on their outer sides, which are arranged between the front ends of the sheath segments. These clamping elements 14 may be z. B. act as protruding from the segment surface clamping projections 14. These can be z. B. integrally formed on the shell segments 12 and integrally formed therewith. In the illustrated first

Embodiment of Fig. 3a, these clamping projections 14 are provided with wedge surfaces 15, that is, the clamping projections 14 themselves are wedge-shaped. FIG. 3b now shows a tensioning profile 13 in the exemplary embodiment as a tensioning strip, which serves for tensioning and thus delivering the shell segments 12 shown in FIG. 3a. For this purpose, the clamping profile 13 on a plurality of counter-elements 16, which are formed in the embodiment as clamping recesses 16 and openings 16. These clamping recesses 16 are in turn also equipped with wedge surfaces 17, so that the clamping recesses 16 are wedge-shaped.

With the help of the clamping profile 13 shown in Fig. 3b, the shroud segments 12 shown in Fig. 3a can be clamped together. Reference is made to Fig. 3c, because there it can be seen that the clamping profiles 13 and their clamping recesses 16 so cooperate with the clamping projections 14 on the shell segments 12 that the shell segments 12 in the course of a longitudinal displacement along the longitudinal direction L of the clamping profile 13 in the radial Direction delivered and therefore be curious. Because in the course of the displacement of the clamping profile 13 (relative to the shell segments) along the longitudinal direction L, the wedge surfaces 17 of the clamping recesses 16 cooperate with the wedge surfaces 15 of the clamping projections 14, so that the shell segments 12 contracted in the region of their longitudinal ends 18 and consequently be clamped in the tangential direction, so that the longitudinal gap 19 between the longitudinal ends 18 of the shell segments 12 decreases. In the region of these longitudinal ends 18 and of the longitudinal gap 19, consequently, a tangential delivery takes place in the course of the longitudinal displacement of the clamping profile 13, which, however, leads to a delivery or tension in the radial direction relative to the entire circumference of the stator jacket.

It can be seen in FIGS. 3a to 3c that, in this embodiment, a plurality of clamping projections 14 on the one hand and clamping recesses 16 on the other hand are provided over the length of the stator jacket 3, so that symmetrical infeed is realized over the entire length of the stator. The shell segments 12 on the one hand and the clamping profile 13 are provided with opposing wedges, so that by moving the clamping profile against the shell segments these pressed against each other and so the clamping is adjusted.

Figures 3a to 3c show an embodiment in which the clamping recesses 16 are formed symmetrically with two-sided wedge surfaces 17, so that all clamping projections 14 (both sides) are wedge-shaped. In contrast, Figures 4a to 4c show a modified embodiment in which the clamping recesses 16 are formed asymmetrically with only a single wedge surface 17 each. The clamping recesses 16 are thus formed wedge-shaped only on one side. Accordingly, in two juxtaposed shell segments 12, only the clamping projections 14 of a shell segment are wedge-shaped and the clamping projections 14 of the adjacent shell segment 12 are not wedge-shaped, z. B. web-shaped straight.

The embodiment according to FIGS. 5 a to 5 c corresponds with regard to the configuration of the clamping recesses and the clamping projections of the embodiment according to FIGS. 3 a to 3 c. However, this embodiment differs from the previously discussed embodiments in that the clamping profiles 13 are not each formed in one piece, but are composed of a plurality of (detachable) interconnected and longitudinally successively arranged profile segments 13a,

wherein the profile segments 13a may be connected to each other with connecting elements 13b, z. B. with threaded rods or the like. FIGS. 6a to 6c show an alternative embodiment in which the clamping projections 14 distributed over the length and / or the clamping recesses 16 are not dimensioned identically, but have different dimensions. In this case, an embodiment is shown in which the clamping recesses 16 and / or the clamping projections 14 have different slopes of the wedge surfaces 15, 17. Thus, the delivery over the length of the stator can be made variable.

In Figures 7a to 7c, a further modification of the invention is shown in which although the clamping recesses 16 each have one or more wedge surfaces, for. B. wedge-shaped. The clamping projections 14 themselves, however, are not wedge-shaped, but are formed as a spigot spigot, which are round and are optionally rotatably attached to the shell segments. In this way, the frictional forces can be reduced in the course of the feed movement.

Incidentally, the variants described in the figures illustrated can also be combined with one another. So there is z. B. in the embodiment of Fig. 4a to 4c the possibility distributed over the length to realize different gradients, as shown in Figures 6a to 6c. Moreover, in the embodiment illustrated in FIGS. 3 a to 3 c and 4 a to 6 c and 6 a to 6 c and 7 a to 7 c, it is possible to implement these in several parts analogously to the embodiment according to FIGS. 5 a to 5 c.

Incidentally, FIGS. 8a and 8b show a modified embodiment in which each clamping strip 13 has only one clamping recess 16, which in turn is wedge-shaped at least on one side, preferably on both sides. In the illustrated embodiment, the clamping projections 14 are wedge-shaped, wherein also distributed over the length only a single clamping projection is provided. Also in this embodiment can be realized over the length of a perfect delivery.

Incidentally, it is shown in the figures that one or more adjusting elements 20 are connected to the stator casing or to the shroud segments 12, with which the clamping profiles 13 are displaceable along the longitudinal direction L in order to realize the desired delivery. The adjusting elements 20 may be set screws, threaded rods or the like. These adjusting elements 20 preferably pass through recesses in the end attachment flanges 21 of the shell segments 12. These openings 22 may, for. B. be equipped with an internal thread, so that screws 20 can screw into the threaded holes in the mounting flanges 21, wherein the screws 20 then work with their front ends against the front ends of the clamping profiles 13. These embodiments are shown in the figures. Alternatively, however, there is also the possibility that the adjusting elements 20, z. B. screws or threaded rods engage in end-side threaded holes or blind holes in the clamping profiles, in which case preferably slot-like perforations are provided in the mounting flanges to allow a displacement of the adjusting in the tangential or radial direction in the course of the feed movement. In this variant, it is for example

possible that the adjusting elements (for example, screws) via corresponding projections or the like (for example via the screw heads) are supported on the mounting flanges, so that in the course of screwing into the threaded bore an adjusting movement is realized. Incidentally, it is alternatively also possible to arrange or support the adjusting elements on the connecting flanges 10, 11 of the housings 4, 5. This is not shown in the figures.

The figures show embodiments in which the stator shell 3 consists of several separate shell segments 12 and also the stator 1 itself preferably consists of a plurality Statorteilschalen 1 a, 1 b. However, the principle according to the invention with the terminal block 13 shown in FIG. 3 can also be realized in the case of a one-piece, longitudinally slotted stator jacket. Incidentally, there is optionally also the possibility that the stator jacket 3 consists of several shell segments, which are arranged one behind the other along the length of the stator jacket and which are preferably clamped together with the clamping profiles according to the invention. Thus, in particular, there is also the possibility that in the case of the stator jacket 3 shown in the figures, which consists of several separate shell segments 12, each of these shell segments 12 again viewed over the length of two or more individual shell segments or segment sections, which then be held together using the clamping profiles and braced against each other. Such an embodiment is not shown in the figures.

Claims

1 . Stator assembly for an eccentric screw pump with at least one stator (1) of elastic material, - a stator (1) in the circumferential direction at least partially surrounding and extending along the longitudinal direction stator shell (3), which consists of at least two sheath segments (12) and a Statorspannvorrichtung forms, with the stator is deliverable, characterized in that the shell segments (12) between the front ends are each provided with one or more clamping elements (14), that the shell segments (12) via one or more along the longitudinal direction (L) extending Clamping profiles (13) are connected to each other, wherein the clamping profiles (13) are each provided with one or more counter-elements (16) which cooperate with the clamping elements (14) in such a form-fitting manner that the shell segments (12) in the course of a longitudinal displacement of the clamping profile ( 13) in the tangential and / or radial direction n.

2. Statoraggregat according to claim 1, characterized in that the clamping elements (14) are formed as protruding from the segment surface clamping projections.

3. Statoraggregat according to claim 1 or 2, characterized in that the counter-elements (16) as Spannausnehmungen, z. B. depressions or openings, are formed, in which engage the clamping projections.

4. Statoraggregat according to one of claims 1 to 3, characterized in that the clamping elements (14) one or more wedge surfaces (15), z. B. at least partially wedge-shaped and / or that the counter-elements (16) one or more wedge surfaces (17), z. B. at least partially wedge-shaped.

5. Statoraggregat according to one of claims 1 to 4, characterized in that the clamping elements (14) are designed as pins, which are preferably designed to be round and optionally rotatably connected to the segment surface or are designed to be rotatable.

6. Statoraggregat according to one of claims 1 to 5, characterized in that the plurality of distributed along the longitudinal direction clamping elements (14) and / or counter-elements (16) are dimensioned differently by z. B. wedge surfaces (15, 17) are provided with different pitch.

7. Statoraggregat according to one of claims 1 to 6, characterized in that the clamping profiles (13) each consist of several z. B. releasably interconnected and longitudinally successively arranged profile segments (13 a) are assembled.

8. Statoraggregat according to one of claims 1 to 7, characterized in that the clamping profiles (13) with adjusting elements (20), z. B. screws or the like, in the longitudinal direction (relative to the shell segments) are displaceable, wherein the adjusting elements (20) z. B. openings in end

Pass through mounting flanges (21) of the shroud segments (12) and / or are supported on end-side mounting flanges (21).

9. Statoraggregat according to one of claims 1 to 8, characterized in that the stator jacket (3) is integrally formed longitudinally slotted and formed by two firmly interconnected shell segments (12) whose longitudinal ends (18) with the interposition of a longitudinal gap (19) against each other oriented and with a clamping profile (13) against each other in the tangential direction can be clamped.

10. Statoraggregat according to one of claims 1 to 8, characterized in that the stator jacket (3) is formed in several parts longitudinally divided and composed of several separate shell segments (12) whose longitudinal ends (18) in pairs with the interposition of a longitudinal gap (19) against each other are oriented and each with a clamping profile (13) against each other in the tangential direction can be clamped.

1 1. Stator unit according to one of claims 1 to 10, characterized in that the sheath segments (12) more, z. B. three or more, distributed along the longitudinal direction and spaced apart clamping elements (14), z. B. clamping projections, and / or that the clamping profiles (13) more, z. B. three or more along the longitudinal direction (L) distributed and spaced-apart counter-elements (16), z. B. clamping recesses have.

12. Statoraggregat according to one of claims 1 to 1 1, characterized in that the stator (1) is arranged detachably in the stator casing (12).

13. Statoraggregat according to one of claims 1 to 12, characterized in that the stator (1) formed as a multi-part longitudinally divided stator and a plurality of Statorteilschalen, z. B. half shells, is composed.

14. Statoraggregat according to one of claims 1 to 13, characterized in that the stator (1) is formed or equipped on the outer peripheral side with one or more Verdrehsicherungen, z. B. with bars.

15. Eccentric screw pump with a stator according to one of claims 1 to 14 and with a in the stator (1) rotatable rotor.