Rotary piston pump with a piston formed by a plurality of plates filled with polymer material

Abstract

The invention relates to a rotary piston pump comprising a housing with a housing interior, an inlet opening, and an outlet opening; a first rotary piston which is mounted within the housing interior in a rotational manner about a first rotational axis; and a second rotary piston which is mounted within the housing interior in a rotational manner about a second rotational axis. The first rotary piston and the second rotary piston engage into each other in a region between the first and the second axis and displace liquid. The first rotary piston has a frame assembly which comprises multiple mutually spaced plates and is at least partly filled and enveloped with a polymer material.

Claims

1. A rotary pump, comprising: a housing with a housing interior; an inlet opening through which liquid can flow into the housing interior; an outlet opening through which liquid can flow out of the housing interior; a first rotary piston rotatably mounted about a first axis of rotation within the housing interior; and a second rotary piston rotatably mounted about a second axis of rotation within the housing interior; wherein the first rotary piston and the second rotary piston mesh in a region between the first and the second axis and displace fluid, and the first rotary piston has a framework arrangement comprising a plurality of mutually spaced-apart plates and the framework arrangement is at least partially filled and at least partially enveloped with a polymer material; wherein each of the plurality of mutually spaced-apart plates has the spacer element formed integrally thereon and produced by bending deformation of a portion of one of the plurality of mutually spaced-apart plates, the spacer element positioning the plurality of mutually spaced-apart plates at a predetermined spacing from one another; wherein each of the plurality of mutually spaced-apart plates has at least one spacer element abutment surface situated at a predetermined height above and pointing away from a plane of one of the plurality of spaced-apart plates in contact with an adjacent one of the plurality of mutually spaced-apart plates; and wherein three spacer element abutment surfaces are situated at a predetermined height above and pointing away from a plane of the one of the plurality of mutually spaced-apart plates in contact with an adjacent one of the plurality of mutually spaced-apart plates.

2. The rotary piston pump as claimed in claim 1, wherein the plurality of mutually spaced-apart plates are formed from a material that differs from the polymer material.

3. The rotary piston pump as claimed in claim 2, wherein the plurality of mutually spaced-apart plates are formed from a metallic material.

4. The rotary piston pump as claimed in claim 2, wherein the polymer material is a resiliently elastic material.

5. The rotary piston pump as claimed in claim 1, wherein the plurality of mutually spaced-apart plates are oriented parallel to one another.

6. The rotary piston pump as claimed in claim 1, wherein the spacing between the plurality of mutually spaced-apart plates is equal.

7. The rotary piston pump as claimed in claim 1, wherein each spacer element abutment surface comprises a mutually aligned and mutually spaced-apart spacer element abutment surface piece, and two adjacent plates of the plurality of mutually spaced-apart plates are in direct contact with one another via the spacer element abutment surfaces.

8. The rotary piston pump as claimed in claim 1, wherein the spacer element is formed from a material which differs from the polymer material.

9. The rotary piston pump as claimed in claim 8, wherein the spacer element is formed from a material that has a coefficient of thermal expansion which is less than 75% of the coefficient of thermal expansion of the polymer material.

10. The rotary piston pump as claimed in claim 1, wherein the polymer material comprises a prefabricated polymer component inserted in a cross-linked state through mutually aligned openings in the plurality of mutually spaced-apart plates, and a polymer material fraction formed by a flowable polymer material component which, in a flowable state, at least partially envelops the plurality of spaced-apart plates and the prefabricated polymer component and is thereafter cross-linked so as to assume a solid state.

11. The rotary piston pump as claimed in claim 1, wherein a mechanical connection between the polymer material and the plurality of mutually spaced-apart plates is formed by any of: adhesive bonding; positive locking between the polymer material and a surface of the plurality of mutually spaced-apart plates that de-limit openings or recesses in the plurality of mutually spaced-apart plates, which openings or recesses are filled with the polymer material; or non-positively locking connection by means of clamping elements which clamp the plates and the polymer material together.

12. The rotary piston pump as claimed in claim 1, wherein the second rotary piston comprises a framework arrangement comprising a plurality of mutually spaced-apart plates, the framework arrangement being at least partially filled and at least partially enveloped with a polymer material.

13. The rotary piston pump as claimed in claim 12, wherein the first and the second rotary piston have an internally situated, non-circular opening that is not filled with the polymer material and the first and second rotary piston, respectively, are rotatably mounted by means of a first and second shaft, respectively, one of the first and second shafts being arranged in the opening.

14. The rotary piston pump as claimed in claim 1, wherein each of the first and the second rotary piston have at least two rotary piston lobes which extend in a helical line along the outer circumference of each of the first and the second rotary pistons, and the plurality of mutually spaced-apart plates have a corresponding geometry with at least two rotary piston lobes.

15. The rotary piston pump as claimed in claim 14, wherein each of the plurality of mutually spaced-apart plates are geometrically identical, and the helical profile is realized by means of a non-circular, helically running outer contour of a drive shaft or hub in a positive locking fit with a central recess of the each of the plurality of mutually spaced-apart plates.

16. The rotary piston pump as claimed in claim 14, wherein the plurality of mutually spaced-apart plates are divided into at least two sets which are pushed onto a shaft or hub with a rectilinear, non-circular outer contour, wherein the plurality of mutually spaced-apart plates within a first set have a first geometry, and the plurality of mutually spaced-apart plates within a second set have a different second geometry, such that the angular position between a non-circular contour of a central recess and the rotary piston lobe differs between the plurality of mutually spaced-apart plates of the first and second sets.

17. A method for producing a rotary piston for a rotary piston pump for conveying particle-laden liquids comprising the steps of: forming a frame arrangement by arranging a plurality of mutually spaced-apart plates; at least partially enveloping the frame arrangement with a polymer material in a flowable state; and connecting the frame arrangement to the polymer material by crosslinking the polymer material; wherein two of the plurality of mutually spaced-apart plates are positioned so as to be mutually spaced apart and parallel to one another by means of at least one of a plurality of spacer elements and which have abutment surfaces for two adjacent plates of the plurality of mutually spaced-apart plates; and wherein each of the plurality of mutually spaced-apart plates has a one of the plurality of the spacer elements formed integrally thereon and produced by bending deformation of a portion of one of the plurality of mutually spaced-apart plates.

18. The method as claimed in claim 17, wherein the frame arrangement comprises the plurality of mutually spaced-apart plates, before being at least partially enveloped with the polymer material, being positioned parallel to and spaced apart from one another by means of the plurality of spacer elements, whereby the spacer elements are enveloped with the polymer material and form part of the rotary piston.

19. The method as claimed in claim 17, wherein the step of at least partial enveloping the plurality of mutually spaced-apart plates with the polymer material is performed according to a method comprising the additional steps of: filling a first fraction of the polymer material in a flowable state into a cavity of a casting mold in which the frame arrangement is arranged; cross-linking the fraction of the polymer material; and at least partially enveloping the frame arrangement and the cross-linked first fraction of the polymer material with a second fraction of the flowable polymer material by filling the second fraction of the polymer material in a flowable state into the cavity of the casting mold in which the frame arrangement and the cross-linked first fraction of the polymer material are arranged.

20. The method as claimed in claim 17, wherein, before the plurality of mutually spaced-apart plates are at least partially enveloped with the polymer material, the plurality of mutually spaced-apart plates are wetted with a primer solution either individually or after arrangement as the frame assembly.

21. The method as claimed in claim 17, wherein two of the plurality of mutually spaced-apart plates are positioned so as to be mutually spaced apart and parallel to one another by means of at least one of the plurality of spacer element pieces which are formed on the plurality of mutually spaced-apart plates by bending.

22. A method for producing a rotary piston for a rotary piston pump for conveying particle-laden liquids comprising the steps of: forming a frame arrangement by arranging a plurality of mutually spaced-apart plates; at least partially enveloping the frame arrangement with a polymer material in a flowable state; and connecting the frame arrangement to the polymer material by crosslinking the polymer material; wherein the polymer material is produced by the steps of: prefabricating a block polymer component by crosslinking a prefabrication fraction of the polymer material before the formation of the frame arrangement; arranging the block polymer component in openings or recesses in the plurality of mutually spaced-apart plates; arranging the plurality of mutually spaced-apart plates and the block polymer component in a cavity of a casting mold; at least partially enveloping the plates and the block polymer component with a flowable fraction of the polymer material in the state of a flowable polymer material by virtue of the flowable polymer material being filled into the cavity of the casting mold; and crosslinking the flow fraction of the polymer material such that it assumes a solid state in the cavity of the casting mold.

23. A rotary piston for a rotary piston pump for conveying particle-laden liquids comprising a frame arrangement which comprises multiple mutually spaced-apart plates, wherein the frame arrangement is at least partially filled and at least partially enveloped with a polymer material; wherein each of the plurality of mutually spaced-apart plates has a spacer element formed integrally thereon and produced by bending deformation of a portion of one of the plurality of mutually spaced-apart plates, the spacer element positioning the plurality of mutually spaced-apart plates at a predetermined spacing from one another; wherein each of the plurality of mutually spaced-apart plates has at least one spacer element abutment surface situated at a predetermined height above and pointing away from a plane of one of the plurality of spaced-apart plates in contact with an adjacent one of the plurality of mutually spaced-apart plates; and wherein three spacer element abutment surfaces are situated at a predetermined height above and pointing away from a plane of the one of the plurality of mutually spaced-apart plates in contact with an adjacent one of the plurality of mutually spaced-apart plates.

24. The rotary piston as claimed in claim 23, wherein the rotary piston is produced in accordance with a method comprising the steps of: forming a frame arrangement by assembling the plurality of mutually spaced-apart plates; at least partially enveloping the frame arrangement with a polymer material in a flowable state; and connecting the frame arrangement to the polymer material by crosslinking the polymer material.

25. A rotary pump, comprising: a housing with a housing interior; an inlet opening through which liquid can flow into the housing interior; an outlet opening through which liquid can flow out of the housing interior; a first rotary piston rotatably mounted about a first axis of rotation within the housing interior; and a second rotary piston rotatably mounted about a second axis of rotation within the housing interior; wherein the first rotary piston and the second rotary piston mesh in a region between the first and the second axis and displace fluid, and the first rotary piston has a framework arrangement comprising a plurality of mutually spaced-apart plates and the framework arrangement is at least partially filled and at least partially enveloped with a polymer material; wherein each of the plurality of mutually spaced-apart plates has one of a plurality of spacer elements formed integrally thereon, each of the plurality of spacer elements positioning the plurality of mutually spaced-apart plates at a predetermined spacing from one another; wherein each of the plurality of mutually spaced-apart plates has at least one spacer element abutment surface situated at a predetermined height above and pointing away from a plane of one of the plurality of spaced-apart plates in contact with an adjacent one of the plurality of mutually spaced-apart plates; wherein each of the first and the second rotary piston have at least two rotary piston lobes which extend in a helical line along the outer circumference of each of the first and the second rotary pistons, and the plurality of mutually spaced-apart plates have a corresponding geometry with at least two rotary piston lobes; and wherein each of the plurality of mutually spaced-apart plates are geometrically identical, and the helical profile is realized by means of a non-circular, helically running outer contour of a drive shaft or hub in a positive locking fit with a central recess of the each of the plurality of mutually spaced-apart plates.

26. A rotary pump, comprising: a housing with a housing interior; an inlet opening through which liquid can flow into the housing interior; an outlet opening through which liquid can flow out of the housing interior; a first rotary piston rotatably mounted about a first axis of rotation within the housing interior; and a second rotary piston rotatably mounted about a second axis of rotation within the housing interior; wherein the first rotary piston and the second rotary piston mesh in a region between the first and the second axis and displace fluid, and the first rotary piston has a framework arrangement comprising a plurality of mutually spaced-apart plates and the framework arrangement is at least partially filled and at least partially enveloped with a polymer material; wherein each of the plurality of mutually spaced-apart plates has one of a plurality of spacer elements formed integrally thereon, each of the plurality of spacer elements positioning the plurality of mutually spaced-apart plates at a predetermined spacing from one another; wherein each of the plurality of mutually spaced-apart plates has at least one spacer element abutment surface situated at a predetermined height above and pointing away from a plane of one of the plurality of spaced-apart plates in contact with an adjacent one of the plurality of mutually spaced-apart plates; and wherein the rotary piston has a plurality of rotary piston lobes which extend in a helical line along the outer circumference of the rotary piston, and the plurality of mutually spaced-apart plates have a corresponding geometry with a plurality of rotary piston lobes, each of the plurality of rotary piston lobes of the plurality of mutually spaced-apart plates having one of the plurality of spacer elements formed integrally thereon defining the spacer element abutment surface on each of the plurality of rotary piston lobes at a predetermined and equal radial distance from the axis of the rotary piston and proximate a distal end of each of the plurality of spaced apart plates and at predetermined height above and pointing away from a plane of the one of the plurality of mutually spaced-apart plates in contact with an adjacent one of the plurality of mutually spaced-apart plates.

27. The rotary piston pump as claimed in claim 26, wherein three spacer element abutment surfaces are situated at a predetermined height above and pointing away from a plane of the one of the plurality of mutually spaced-apart plates in contact with an adjacent one of the plurality of mutually spaced-apart plates.

28. The rotary piston pump as claimed in claim 26, wherein the plurality of spacer elements are produced by bending deformation of a portion of one of the plurality of mutually spaced-apart plates.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) A preferred embodiment of the invention will be described on the basis of the appended figures, in which:

(2) FIG. 1 is a perspective view of a rotary piston according to the invention obliquely from the front;

(3) FIG. 1a is a view as per FIG. 1 without polymer material;

(4) FIG. 1b is a view as per FIG. 1 without polymer material having two different sets of spaced-apart plates;

(5) FIG. 2 is a perspective view of the embodiment as per FIG. 1 obliquely from the side;

(6) FIG. 2a is a view as per FIG. 2 without polymer material;

(7) FIG. 3 is a frontal view of the embodiment as per FIG. 1;

(8) FIG. 3a is a view as per FIG. 3 without polymer material;

(9) FIG. 4 is a side view of the embodiment as per FIG. 1;

(10) FIG. 4a is a view as per FIG. 4 without polymer material;

(11) FIG. 5 is a perspective view obliquely from the side of the hub body of the embodiment as per FIG. 1a;

(12) FIG. 6 is a frontal view of a frame sheet of the embodiment as per FIG. 1;

(13) FIG. 7 is a perspective view of a frame sheet of the embodiment as per FIG. 1;

(14) FIG. 8 is a frontal view of a spacer element of the embodiment as per FIG. 1;

(15) FIG. 9 is a perspective view of a spacer element of the embodiment as per FIG. 1; and

(16) FIG. 10 is a perspective view of the pump housing.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(17) As referenced in the Figures, the same reference numerals may be used herein to refer to the same parameters and components or their similar modifications and alternatives. For purposes of description herein, the terms “upper,” “lower,” “right,” “left,” “rear,” “front,” “vertical,” “horizontal,” and derivatives thereof shall relate to the present disclosure as oriented in FIG. 1. However, it is to be understood that the present disclosure may assume various alternative orientations and step sequences, except where expressly specified to the contrary. It is also to be understood that the specific devices and processes illustrated in the attached drawings, and described in the following specification, are simply exemplary embodiments of the inventive concepts defined in the appended claims. Hence, specific dimensions and other physical characteristics relating to the embodiments disclosed herein are not to be considered as limiting, unless the claims expressly state otherwise. The drawings referenced herein are schematic and associated views thereof are not necessarily drawn to scale.

(18) FIG. 10 shows a rotary lobe pump with a housing 100 with first rotary piston and second rotary piston 140, 145, respectively, arranged inside said housing. The housing 100 comprises a housing interior 100′; an inlet opening 110 through which liquid can flow into the housing interior 100′; an outlet opening 120 through which liquid can flow out of the housing interior 100′; the first rotary piston 140 rotatably mounted about a first axis of rotation 140′ within the housing interior 100′; and the second rotary piston 145 rotatably mounted about a second axis of rotation 145′ within the housing interior 100′; wherein the first rotary piston and a second rotary piston mesh in a region between the first and the second axis 140′, 145′ and displace fluid.

(19) As a preferred embodiment, a three-lobe rotary piston with twisted rotary piston lobes 41, 42, 43, which follow a helical line, is shown. It is basically to be understood that the invention is applicable to rotary pistons with straight rotary piston lobes or twisted rotary piston lobes or rotary piston lobes with a geometry that differs from these, and can be used for rotary pistons with two, three, four, five, or more rotary piston lobes.

(20) The rotary piston according to the invention has a rotary piston hub 10 that is typically produced from a metallic material. The rotary piston hub 10 has a cylindrical inner geometry with a groove 11 for the connection fixedly in terms of torque to a drive shaft by means of a parallel key. Use may basically also be made of other shaft-hub connections which are suitable for transmitting torque from the shaft to the hub, for example, polygonal shafts, which interact with a corresponding inner geometry of a polygonal hub, conical connections which connect the shaft to the hub by means of a non-positively locking connection, toothings between shaft and hub, and the like. The rotary piston hub 10 is surrounded by three rotary piston lobes 41, 42, 43, which are arranged around the circumference of the rotary piston hub 10 with a 120° pitch, and which, in an axial direction of the rotary piston hub 10, twist through approximately 60° in the circumferential direction along a helical line. It is basically to be understood that the number of degrees of twist should be selected in a manner dependent on the number of lobes in order to achieve pulsation-free operation, a leakage-free pump action, and prevention of a backward flow through the pump in all rotational positions of the rotary pistons. Accordingly, in the case of two-lobe pistons, a twist of the lobes through 90°, in the case of three-lobe pistons, a twist of the lobes through 60°, and in the case of four-lobe pistons, a twist of the lobes through 45°, and generally a twist of the lobes through 180° divided by the number of lobes, should be adhered to or not exceeded.

(21) The rotary piston lobes 41, 42, 43 are coated both on their flanks and at their tips and end sides with a polymer material. Said polymer material is also partially formed in the interior space of the rotary piston lobes 41, 42, 43; the exact configuration will be discussed in detail below.

(22) As polymer material, use is preferably made of a resiliently elastic material, which may in particular be a rubber material hardened by vulcanization.

(23) FIG. 1a, 1b, 2a, 3a and 4a show a frame structure that serves for producing a connection rigid in terms of torque between the rotary piston lobes and the rotary piston hub 10. The frame structure comprises multiple frame sheets 20a, 20b, 20c, 20d, etc., which basically correspond to the cross-sectional contour in an axial cross section of the rotary piston, but which are of smaller dimensions than the cross-sectional dimension. FIG. 1b shows a frontal view according to FIG. 1a of an embodiment having two different sets of spaced-apart plates. FIG. 1b shows a first set of plates 20a′, 20b′, 20c′ and a second set of plates 20a″, 20b″, 20c″, which are pushed onto a hub with a rectilinear, non-circular outer contour. The plates of the first set have a first geometry and the plates of the second set have a second geometry. The difference in geometry lies in the interface of the plates to the hub.

(24) Each frame sheet consequently has three lobes 21, 22, 23, which are arranged with a pitch of 120° with respect to one another. Furthermore, each frame sheet has a central recess 24; in this regard, see FIGS. 6 and 7. Said central recess 24 is designed so as to produce a connection fixed in terms of torque between the frame sheet and the rotary piston hub 10. In the preferred embodiment, this is achieved by virtue of the recess being substantially circular and having three grooves 25 distributed over the circumference, which grooves 25 interact in positively locking fashion with three webs 12, 13, 14, which are formed congruently with respect to said grooves 25, on the outer surface of the rotary piston hub 10, as can be seen from FIG. 5. It is basically to be understood that the connection fixed in terms of torque between frame sheet and rotary piston hub may be implemented in different ways; alternatively, to the embodiment illustrated here, it is also possible for embodiments to be formed with a single groove and with a corresponding single web, and alternatively, other connection types may be implemented with a toothing or the like. In the case of the embodiment shown, the circumferential length of the grooves 25 in the frame sheet amounts to approximately 60°, giving rise to a uniform distribution of the three set-back circumferential parts and the three protruding circumferential parts of the central recess 24 in the frame sheet. Here, the groove-like recess is arranged in each case in the region of the rotary piston lobes in order to permit expedient material utilization and a slim form of the frame sheet in the region between the rotary piston lobes.

(25) Each frame sheet furthermore has a circular recess 26, 27, 28 in each rotary piston lobe. The frame sheets of the rotary piston according to the invention are, therefore, designed so as to exhibit a maximum material saving while predefining the outer contour of the rotary piston and a connection fixed in terms of torque formed in direct contact with the rotary piston hub 10.

(26) As can be seen from FIG. 5, in an axial longitudinal direction along the circumferential surface of the rotary piston hub, the webs 12, 13, 14 run along a helical line which corresponds to the helical profile of the rotary piston lobes. As a consequence of this, the inner frame of the rotary piston according to the preferred embodiment can be constructed from multiple frame sheets which are all of corresponding design. Aside from this preferred embodiment, other refinements of the rotary piston according to the invention are also conceivable and advantageous in certain applications. For example, an embodiment may also be advantageous in which the webs are formed rectilinearly in an axial longitudinal direction on the rotary piston hub. In conjunction with the frame sheets shown in FIGS. 6 and 7, this refinement yields a rotary piston with straight rotary piston lobes. Furthermore, in the case of a rotary piston hub of said type being formed with straight webs, a helical profile of the rotary piston lobes can be achieved by virtue of frame sheets of different design being used in alternation. This different design must in this case consist in that the angular offset between the grooves 25, on the one hand, and the rotary piston lobe sections 21, 22, 23, on the other hand, differs in the different embodiments of the frame sheets. Here, the angular difference arises from the desired gradient of the rotary piston lobes along the helical profile and the axial spacing of the frame sheets on the rotary piston hub 10.

(27) As can be clearly seen in particular from FIG. 2a and FIG. 4a, the rotary piston according to the invention is constructed from a total of ten frame sheets. These frame sheets are arranged on the rotary piston hub 10 so as to be uniformly spaced apart axially over the entire axial length of the rotary piston. In each case, two adjacent frame sheets are positioned relative to one another by means of three spacer element pieces 30 which form a spacer element. Instead of the spacer element being made up of three spacer element pieces 30, it is in some applications advantageous, for the simplification of the assembly process, for the spacer element to be produced in one piece, for example, by virtue of the three spacer element pieces 30 being connected to one another by means of webs or the like.

(28) A spacer element piece 30 is shown in FIGS. 8 and 9. As can be seen from these Figures, the spacer element piece 30 has a substantially ring-shaped body that has a central axial recess 31. On an end side of the spacer element piece 30, there is formed an encircling shoulder 32. The outer diameter of said shoulder 32 is slightly smaller than the inner diameter of the circular recesses 26, 27, 28 in the frame sheets, and thereby permits positive locking centered positioning of the spacer element piece 30 within said recesses. On the opposite side, the spacer element piece 30 is formed with a planar end surface. As an alternative to this, it is basically possible for a corresponding encircling shoulder, which realizes defined positioning of two adjacent frame sheets with respect to one another, to also be formed on the opposite side. In the case of the spacer element pieces being used for a rotary piston with straight rotary piston lobes, the shoulders on the two end sides may in this case be coaxial with respect to one another; in the case of the spacer element piece 30 being used for a rotary piston with a helical profile of the rotary piston lobes, the shoulders should be formed with a corresponding eccentric offset with respect to one another.

(29) Each spacer element piece 30 furthermore has, in one circumferential section, a rounded recess 33, the radius of which corresponds to the radius of the outer surface of the rotary piston hub 10. The spacer element pieces 30 can in this way be positioned so as to lie directly on the rotary piston hub 10 and be secured against relative rotation.

(30) A rotary piston according to the invention is constructed by means of a frame which comprises multiple frame sheets 20 and in each case three spacer element pieces 30 between two adjacent frame sheets 20. By means of this construction, a sturdy frame structure is provided which defines the contour of the rotary piston lobes and exhibits a positive locking connection to the rotary piston hub. It is to be understood that the frame sheets are preferably produced from a metallic material. The spacer element pieces 30 may preferably be produced from a polymer material.

(31) The frame structure constructed in this way with the rotary piston hub is hereinafter filled and enveloped with the polymer material. This filling and enveloping process may, in particular, take place such that three, already-hardened, for example, vulcanized polymer strands, are pushed through the openings 26, 27, 28 of the frame sheets 20, wherein it is particularly advantageous for an elastically deformable polymer material with an outer diameter slightly smaller than the inner diameter of said openings to be used for this purpose in order that it can follow the helical profile in which said openings are staggered relative to one another. Alternatively, it is also possible for prefabricated vulcanizable polymer strands to be inserted into the openings; in this case, the vulcanization of the polymer strands takes place during the subsequent vulcanization of the coating or envelopment with the rest of the polymer material.

(32) Following this, the frame structure thus prepared, with the prefabricated polymer fractions already inserted, can be encapsulated and enveloped with a liquid polymer material, whereby the cavities within the frame structure are completely filled. By means of the large volume fraction of the already-hardened and crosslinked polymer material, little shrinkage of the polymer material occurs during the course of the crosslinking thereof. In particular, it is also possible for two-stage encapsulation with the liquid polymer material to be performed in a time-offset manner in order, in a first encapsulation process, to realize filling up to, or up to slightly below, the outer edge of the frame sheets, and, in a subsequent second encapsulation process, to realize the complete outer contour with envelopment of the frame. The material thickness is basically dependent on the usage situation and on the overall dimensions of the rotary piston; for example, a material thickness of at least 5 mm of polymer material may be provided between the outer edges of the frame sheets and the outer contour of the rotary piston.

(33) Owing to its construction, the rotary piston according to the invention has a rigid construction that can be subjected to high torque. At the same time, the fraction of metallic material is significantly reduced, whereby the weight of the rotary piston and the consumption of valuable starting materials are considerably reduced. The manufacture of the rotary piston is greatly simplified owing to the possible modularity with the use of identical components. Accordingly, for example, through the use of different rotary piston hubs with different gradients of the webs formed thereon or lengths, it is possible to produce rotary pistons with different gradient of the rotary piston lobes or different lengths in a modular system.

(34) It will be understood by one having ordinary skill in the art that construction of the described present disclosure and other components is not limited to any specific material. Other exemplary embodiments of the disclosure disclosed herein may be formed from a wide variety of materials, unless described otherwise herein.

(35) For purposes of this disclosure, the term “operably coupled” (in all of its forms, couple, coupling, coupled, etc.) generally means the joining of two components (electrical or mechanical) directly or indirectly to one another. Such joining may be stationary in nature or movable in nature. Such joining may be achieved with the two components (electrical or mechanical) and any additional intermediate members being integrally formed as a single unitary body with one another or with the two components. Such joining may be permanent in nature or may be removable or releasable in nature unless otherwise stated.

(36) For purposes of this disclosure, the term “operably connected” (in all of its forms, connect, connecting, connected, etc.) generally means that one component functions with respect to another component, even if there are other components located between the first and second component, and the term “operable” defines a functional relationship between components.

(37) It is also important to note that the construction and arrangement of the elements of the present disclosure as shown in the exemplary embodiments is illustrative only. Although only a few embodiments of the present innovations have been described in detail in this disclosure, those skilled in the art who review this disclosure will readily appreciate that many modifications are possible, e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc. without materially departing from the novel teachings and advantages of the subject matter recited. For example, elements shown as integrally formed may be constructed of multiple parts or elements shown in multiple parts may be integrally formed, the operation of the interfaces may be reversed or otherwise varied, the length or width of the structures and/or members or connector or other elements of the system may be varied, the nature or number of adjustment positions provided between the elements may be varied. It should be noted that the elements and/or assemblies of the system may be constructed from any of the wide variety of materials that provide sufficient strength or durability, in any of the wide variety of colors, textures, and combinations. Accordingly, all such modifications are intended to be included within the scope of the present innovations. Other substitutions, modifications, changes, and omissions may be made in the design, operating conditions, and arrangement of the desired and other exemplary embodiments without departing from the spirit of the present innovations.

(38) It will be understood that any described processes or steps within described processes may be combined with other disclosed processes or steps to form structures within the scope of the present disclosure. The exemplary structures and processes disclosed herein are for illustrative purposes and are not to be construed as limiting.

(39) It is to be understood that variations and modifications can be made on the aforemen-tioned structure and method without departing from the concepts of the present disclosure, and further it is to be understood that such concepts are intended to be covered by the following claims unless these claims by their language expressly state otherwise.