Mechanisms for reducing eddy current losses in seal-less pumps and turbines with direct-drive impellers.

Abstract

Integrated motor pumps (IMPs) or integrated motor turbines (IMTs) include axial field permanent magnet synchronous motors (PMSMs) having a stator sealed by a disc-shaped non-conductive stator cover axially positioned between the stator and the PMSM impeller, such that eddy currents are not generated in the stator cover by the rotating permanent magnets of the impeller. The stator cover may be annular and may be directly attached to the stator housing or pressed against the stator housing by a bracket. The seal may be formed by an adhesive and / or by at least one gasket. The stator cover or bracket may include a flange extending axially adjacent to the stator housing and attached to the stator housing by any combination of interference fit, adhesive, locating screw, or protrusions extending into a recess. In an embodiment, the bracket flange is welded to the stator housing.

Description

Cross-reference to related applications

[0001] This application claims the benefit of U.S. Patent Application No. 18 / 407,054, filed January 8, 2024, the entire contents of which are incorporated herein by reference for all purposes. Application 18 / 407,054 relates to U.S. Patent No. 11,323,003, published May 3, 2022, the entire contents of which are also incorporated herein by reference for all purposes. Technical Field

[0002] This invention relates to pumps and turbines, and more particularly to integrated motor pumps and integrated motor turbines. Background Technology

[0003] refer to Figure 1A Integrated motor pumps (IMPs) and integrated motor turbines (IMTs) (sometimes referred to as “seal-less” pumps and “seal-less turbines” because the housing 104 is not penetrated by a drive shaft) are centrifugal devices that combine an impeller 100 and a motor or generator 102 within a common housing 104. Typically, the impeller 100 is attached to a rotating shaft 114, which is also fixed to a rotor 108. For simplicity, this disclosure sometimes refers only to IMPs, i.e., only to pumps that include a motor. However, it will be understood that the disclosure presented herein applies equally to turbines that include a generator, and that IMPs and other pumps mentioned herein generally refer to both pumps (IMPs) and turbines (IMTs), while motors generally refer to both motors and generators or alternators, unless the context otherwise states or requires.

[0004] Typically, IMPs are immersed in the process fluid, making it important in many cases to hermetically seal their sensitive magnetic and electrical components to protect them from contamination and conductive fluids. The stator assembly typically includes an electrical coil assembly 106, which comprises laminated steel, insulated copper wire, and insulating material. The rotor assembly 108 typically includes an electrical coil assembly (in the case of an asynchronous induction motor) or a permanent magnet assembly (in the case of a synchronous motor).

[0005] like Figures 1A to 1C As illustrated, the rotor 108 and stator 106 in a sealless pump or turbine are typically sealed within concentric cylindrical metal bushings 110, 112. (Reference) Figure 1B and Figure 1C The enlarged view shows that one drawback of this design is that eddy currents 116 are generated in the metal bushing 110 of the stator 106 due to the changing magnetic field 118 penetrating the stator bushing 110 between the stator 106 and the rotor 108. Because the rotor moves synchronously with the time-varying magnetic field, no eddy currents are generated in the bushing 112 of the rotor 108.

[0006] The eddy currents generated in the bushing 110 of the stator 106 represent an electrical load on the motor and reduce overall motor efficiency. The energy generated by the eddy currents 116 in the metal stator bushing 110 is converted into heat, raising the temperature of the stator bushing, which requires cooling. Manufacturers of enclosed motor pumps generally consider these eddy current losses to be acceptable because the welded metal stator bushing 110 is a robust solution and a well-proven, reliable method for hermetically sealing the stator assembly.

[0007] However, for some IMP applications, such as when pumping cryogenic liquids (e.g., liquefied natural gas LN2), and especially liquid hydrogen (LH2), which is much colder than LN2, the temperature rise of the stator bushing 110 due to eddy current 116 can be problematic. With the increasing use of hydrogen as a fuel supply, the collection, transportation, and distribution of LH2 are becoming increasingly important. In particular, “green” hydrogen is expected to play a key role in reducing carbon emissions in the coming decades. The term “green” hydrogen refers to hydrogen produced using renewable clean energy sources such as solar and wind power.

[0008] Renewable energy generators (such as windmills and solar panels) can sometimes be installed near energy consumption locations, such as placing solar panels on building rooftops or installing windmills next to factories. However, this approach is limited by site constraints and economies of scale. Instead, it is generally preferred to construct large-scale green energy facilities in optimal locations, such as large solar panel arrays in deserts or windmill farms in coastal waters, and then transport their power output to remote energy consumption locations. Besides taking advantage of favorable environments and achieving economies of scale, this approach has the advantage of being able to utilize existing distribution networks to benefit a larger number of energy consumers. However, it is still necessary to site such facilities near the consumer's grid.

[0009] Conversely, refer to Figure 1D The green energy produced at a remote location 120, including a water source 124, 122 can be used to produce hydrogen via hydrolysis 126. The hydrogen is compressed 128 and can be distributed to power plants wherever it is needed, similar to natural gas distribution. As with natural gas, liquefying the hydrogen 130 before transport 136 is generally more efficient, eliminating the safety concerns associated with gas pressurization and allowing the increased energy density to be contained within a given container space. Typically, LH2 is stored 132 and then transferred 134 to ships, train cars, or trucks as needed. Finally, after the LH2 has been loaded 136 to the import location 138, the LH2 is transferred 140 and stored 142 in a storage container, from which it can be transferred, for example, by truck 144 to a local power plant.

[0010] This method requires pumping liquid hydrogen (LH2) from liquefaction unit 130 into storage container 132, then unloading 134 and pumping it into a container on a ship or other transport vehicle 136. The LH2 is then pumped from transport vehicle 136 into inlet storage container 140, and finally from local storage 142 into local distribution vehicle 144, such as a truck. Therefore, energy-efficient pumping of LH2 with minimal vapor loss is a key part of this method.

[0011] Therefore, what is needed is an integrated motor pump (IMP) or an integrated motor turbine (IMT) that minimizes or eliminates stator bushing temperature rise caused by eddy currents. Summary of the Invention

[0012] This invention relates to an integrated motor pump (IMP) or integrated motor turbine (IMT) that minimizes or eliminates stator bushing temperature rise due to eddy currents. For simplicity, this disclosure sometimes refers only to IMP, i.e., a pump that includes only a motor. However, it will be understood that the disclosure presented herein applies equally to turbines that include generators, and that IMP and other pumps mentioned herein generally refer to both pumps (IMP) and turbines (IMT), while motors generally refer to both motors and generators or alternators, unless the context otherwise states or requires.

[0013] The disclosed IMP or IMT includes an axial field permanent magnet synchronous motor (PMSM). In embodiments, the disclosed IMP or IMT implements a “direct drive” configuration similar to that disclosed by the applicant in U.S. Patent 11,323,003, the entire contents of which are incorporated herein by reference for all purposes. Instead of being formed as elongated cylinders, the stator “bushing” is a stator cover shaped as an annular disk, due to the axial alignment of the permanent magnets and stator coils. According to the invention, the stator cover is non-metallic and non-conductive, thereby preventing the generation of eddy currents in the stator cover.

[0014] Because the stator cover is non-metallic, welding the stator cover to the stator housing is impossible. Instead, embodiments of the invention provide inner and outer gaskets that form and maintain the integrity of the seal even at low temperatures. In embodiments, the stator cover is securely pressed against the gasket by an inner and outer support. In some of these embodiments, the support is secured to the stator housing by welding the lower edge of the support to the stator housing (e.g., by electron beam welding). In other embodiments, the support forms a friction fit with the stator housing, is attached to the stator housing by locating screws, and / or by adhesive.

[0015] In another embodiment, the stator cover is directly attached to the stator housing. In this embodiment, the radially outer and radially inner peripheries of the stator cover are attached to the axial edges of the stator housing by an adhesive. In some of these embodiments, the adhesive attachment also forms a seal between the stator cover and the stator housing, eliminating the need for gaskets.

[0016] In other embodiments of these examples, the stator cover extends radially inward and outward beyond the stator housing and includes an inner cover flange and an outer cover flange that extend axially adjacent to the inner and outer walls of the stator housing and are attached to the stator housing by interference fit, adhesive attachment, or similar attachment means known in the art. The embodiments include any combination of the above attachment mechanisms for attaching the bracket or cover flange to the stator housing, except that the cover flange cannot be welded because the cover is non-metallic.

[0017] This invention relates to an integrated motor-pump module (IMP) or an integrated motor-turbine module (IMT), comprising a module housing configured to allow fluid to flow from its inlet to its outlet; a stator housing housed within and fixed to the module housing; a shaft extending axially proximally from the stator housing; an impeller rotatable with or about the shaft; a plurality of permanent magnets fixed to the distal side of the impeller and configured to pass near the proximity of the stator housing as the impeller rotates about the shaft; a plurality of stator coils housed within the stator housing and configured to approach the permanent magnets as they pass near the proximity of the stator housing; the permanent magnets and stator coils being axially separated by a rotor-stator gap; and a non-conductive stator cover within the rotor-stator gap, the stator cover being fixed to the stator housing and forming a cover seal configured to prevent process fluid from entering the interior of the stator housing.

[0018] In one embodiment, the cover seal includes at least one gasket located between the stator cover and the stator housing.

[0019] Any of the embodiments described above may be an annular embodiment, wherein the stator housing extends about an axis and the stator cover is configured as an annular disk.

[0020] In some of these annular embodiments, the cover seal includes an inner gasket radially adjacent to the inner edge of the annular stator cover and an outer gasket radially adjacent to the outer edge of the annular stator cover.

[0021] Any embodiment of the annular embodiments may include a pair of brackets configured to radially overlap the inner and outer peripheries of the stator cover, respectively, the brackets being secured to the stator housing and configured to press the stator cover against the stator housing. In some embodiments of these embodiments, the brackets are attached to the stator housing by at least one of welding and adhesive attachment. In any embodiment of these embodiments, the brackets may include a bracket flange extending distally adjacent to radially inner and outer surfaces and radially outer outer surface of the stator housing. In some embodiments of these embodiments, the bracket flange forms an interference fit with the stator housing. In other embodiments of these embodiments, the bracket flange includes a radial protrusion extending into a recess in the stator housing, or the stator housing includes a radial protrusion extending into a recess in the bracket flange. In other embodiments of these embodiments, the bracket flange is attached to the stator housing by a locating screw. In yet another embodiment of these embodiments, the bracket flange is welded to the stator housing. In some embodiments of these embodiments, the bracket flange is welded to the stator housing by electron beam welding.

[0022] Alternatively, the stator cover can be directly attached to the stator housing. In some of these embodiments, the stator cover is directly attached to the stator housing using an adhesive. In some of these embodiments, the cover seal is formed by an adhesive.

[0023] In any of these annular embodiments, the stator cover may include a cover flange extending distally from radially inner and outer surfaces and radially outer outer surface of the stator housing. The cover flange may form an interference fit with the stator housing. In other embodiments, the cover flange is attached to the stator housing by an adhesive. In other embodiments, the cover flange is attached to the stator housing by a locating screw. In other embodiments, the cover flange includes a radial protrusion extending into a recess in the stator housing, or the stator housing includes a radial protrusion extending into a recess in the cover flange.

[0024] The features and advantages described herein are not exhaustive, and in particular, many additional features and advantages will be apparent to those skilled in the art from the accompanying drawings, description, and claims. Furthermore, it should be noted that the language used in this specification has been chosen primarily for readability and instructional purposes, and not to limit the scope of the subject matter. Attached Figure Description

[0025] Figure 1A This is a cross-sectional view of a seal-less pump from the prior art;

[0026] Figure 1B It is illustrated according to Figure 1A A simplified cross-sectional view of the radial extension of the magnetic field of the pump from the rotor assembly to the stator coil.

[0027] Figure 1C This is a close-up view of a portion of Figure 2, showing the generation of eddy currents in the stator bushing of the stator;

[0028] Figure 1D It is a flowchart illustrating the use of liquid hydrogen, a technology in the prior art, as a medium for transferring energy from green energy production sites to energy consumption sites;

[0029] Figure 2A This is a cross-sectional view of the IMP or IMT in an embodiment of the present invention, wherein the view is drawn to scale except for elements 210 and 212;

[0030] Figure 2B It is drawn to scale. Figure 2A A close-up view of a portion of the IMP or IMT module;

[0031] Figure 3 yes Figure 1A A simplified comparison of the shape of the existing stator bushing with that of the annular stator cover according to an embodiment of the present invention;

[0032] Figure 4 This is a simplified diagram illustrating the stator cover being axially penetrated by a magnetic field according to the present invention;

[0033] Figure 5A This is a cross-sectional view of the stator in an embodiment of the present invention drawn to scale, wherein the stator cover is pressed against the gasket by an inner bracket and an outer bracket welded to the stator housing;

[0034] Figure 5B It is drawn to scale. Figure 5A A close-up view of the stator;

[0035] Figure 6 This is a close-up view of the stator drawn to scale, which is similar to... Figure 5A However, the bracket is fixed to the stator housing by interference fit and / or adhesive;

[0036] Figure 7 This is a close-up view of an embodiment of the invention drawn to scale, wherein the stator cover is directly bonded and sealed to the stator housing by an adhesive;

[0037] Figure 8 This is a close-up view of an embodiment of the invention drawn to scale, wherein the stator cover is sealed to the stator housing by a gasket and directly bonded to the stator housing by an interference fit and / or adhesive bonding between the axial inner cover flange and the axial outer cover flange and the stator housing;

[0038] Figure 9This is a close-up view of an embodiment of the invention drawn to scale, wherein the stator cover is sealed to the stator housing by a gasket and is attached to the stator housing by extending an inwardly projecting protrusion provided on the cover flange into a recess provided in the stator housing;

[0039] Figure 10A This is a close-up view of an embodiment of the invention drawn to scale, wherein the stator cover is sealed to the stator housing by a gasket and attached to the stator housing by a plurality of locating screws inserted through a channel hole provided in the cover flange and screwed into a threaded hole provided in the stator housing; and

[0040] Figure 10B This is a close-up view of an embodiment of the invention drawn to scale, wherein the stator cover is sealed to the stator housing by a gasket and attached to the stator housing by locating screws that are screwed into threaded holes provided in the cover flange and press against the stator housing. Detailed Implementation

[0041] This invention relates to an integrated motor pump (IMP) or integrated motor turbine (IMT) that minimizes or eliminates stator bushing temperature rise due to eddy currents. For simplicity, this disclosure sometimes refers only to IMP, that is, only to pumps including a motor. However, it will be understood that the disclosure presented herein applies equally to turbines including generators, and that IMP and other pumps mentioned herein generally refer to both pumps (IMP) and turbines (IMT), while motors generally refer to both motors and generators or alternators, unless the context otherwise states or requires.

[0042] The disclosed IMP or IMT includes an axial field permanent magnet synchronous motor (PMSM). Reference Figure 2A and Figure 2B In embodiments, the disclosed IMP or IMT implementation is similar to a “direct drive” configuration disclosed by the applicant in U.S. Patent 11,323,003, the entire contents of which are incorporated herein by reference for all purposes. Unlike configuring the armature 108 and stator 106 in a separate motor 102 to drive shaft 114, which drives impeller 100 (e.g., Figure 1AAs illustrated, the disclosed IMP or IMT includes a permanent magnet 204 directly attached to the impeller 202 and arranged such that it is adjacent to and axially aligned with stator coils 208 disposed in the stator housing 206, allowing the stator to apply torque directly to the impeller 202, rather than indirectly to the impeller 100 by applying torque to the shaft 114. In some applications, the shaft 216 is directly or indirectly and firmly anchored to the stator housing 206, while the impeller 202 is rotatably supported on the shaft 216 by bearings 214, such that only the impeller 202, the permanent magnet 204, and the bearings 214 rotate. In other embodiments, the impeller 202 is fixed to the shaft 216, and the shaft 216 is supported by bearings such that it rotates together with the impeller 202.

[0043] Figure 2A The figure illustrates the IMP in this embodiment, which is configured to draw fluid from module inlet 228 and deliver the fluid to module outlet 230. The "rotor" (i.e., the assembly of rotating components) in the IMP module 200 includes an impeller 202 and a plurality of permanent magnets 204 cooperating with the impeller 202. The IMP module 200 also includes a stator housing 206 that houses stator coils 208 positioned axially opposite the permanent magnets 204.

[0044] The stator coil 208 is excited by a power supply 210 driven by a controller 212, and the magnet 204 and the stator coil 208 work together to function as a synchronous motor that applies rotational torque directly to the impeller 202. In some embodiments, the power supply 210 is an adjustable speed drive (ASD), such as a variable frequency drive (VFD), which makes the rotational speed of the impeller variable.

[0045] In addition to the impeller 202 and permanent magnet 204, the rotor includes a bearing 214 configured to allow the rotor to rotate about a fixed, non-rotating shaft 216, which acts as a short "support". In the illustrated embodiment, the bearing 214 is product-lubricated, and the shaft 216 is firmly anchored to the stator housing 206, which is firmly attached to the module housing 218. The shaft 216 is only slightly longer than the bearing 214 and does not rotate. Figure 2B As can be seen in the close-up partial view, only a very narrow gap 226 separates the permanent magnet 204 from the stator coil 208.

[0046] refer to Figure 3 Because the permanent magnet 204 and the stator coil 208 are axially aligned, instead of being configured as an elongated cylinder 110, the stator “shoulder” is an annular stator cover 300.

[0047] According to the present invention, reference Figure 4Instead of welding the metal cover to the stator housing, a non-magnetic, non-conductive stator cover 300 is sealed to the stator housing 206, allowing the magnetic field 118 to extend axially from the permanent magnet 204 across the rotor-stator gap 226, through the non-conductive stator cover 300, and to reach the stator coil 206. Because the stator cover 300 is non-conductive, no eddy currents are generated in the stator cover 300 through the magnetic field.

[0048] exist Figures 5A to 6 In this embodiment, the inner gasket 500 and the outer gasket 502 form a seal between the annular stator cover 300 and the stator housing 206. In the illustrated embodiment, the inner bracket 524 and the outer bracket 504, including axially extending bracket flanges 520, 526, securely press the stator cover 300 against the O-rings 500, 502 and maintain the integrity of the seal even at low temperatures. Figure 5A and Figure 5B In the stator housing 206, supports 504 and 524 are fixed to the stator housing 206 by welds 506 and 528 at the distal edges of supports 504 and 524, which are formed, for example, by electron beam welding.

[0049] refer to Figure 6 In other embodiments, the bracket flanges 520, 526 are secured to the stator housing 206 by interference fit and / or by applying an adhesive to the interfaces 518, 530 between the bracket flanges 520, 526 and the stator housing 206.

[0050] refer to Figure 7 In other embodiments, the stator cover 300 is directly fixed to the stator housing 206. Figure 7 In one embodiment, the axially outer and axially inner peripheries of the annular stator cover 300 are attached to the axially proximal inner and axially proximal outer edges of the stator housing 206 by adhesive 512. In the illustrated embodiment, the seal between the stator cover 300 and the stator housing 206 is entirely formed by adhesive 512, and gaskets 500 and 502 are omitted.

[0051] exist Figure 8 In one embodiment, the stator cover further includes an inner cover flange 532 and an outer cover flange 514, which extend axially distally along the radially inner and outer surfaces and the radially outer outer surface of the stator housing 206. In the illustrated embodiment, the cover flanges 514, 532 are secured to the stator housing 206 by an interference fit and / or by an adhesive applied to interfaces 522, 534 between the cover flanges 514, 532 and the stator housing 206.

[0052] Figure 9 The embodiments are similar to Figure 8In addition to the cover flanges 514, 532 being at least partially secured to the stator housing 206, this is because inwardly projecting protrusions 516, 538 at the distal edges of the inner cover flange 532 and the outer cover flange 514 extend into corresponding recessed rings 508, 536 disposed in the stator housing 206. In a similar embodiment, outwardly projecting protrusions are disposed in the stator housing 206, extending into recessed rings disposed on the inner surfaces of the cover flanges 514, 532.

[0053] Figure 10A The embodiments are similar to Figure 8 In addition to the cover flanges 514 and 532 being at least partially fixed to the stator housing 206, the positioning screws 540 and 542 are inserted through the channel holes provided in the cover flanges 514 and 532 and screwed into the threaded holes provided in the stator housing 206. Figure 10B The embodiments are similar, except that the positioning screws 540 and 542 are screwed into the threaded holes provided in the cover flange and press against the stator housing 206.

[0054] The embodiments include any combination of the above mechanisms for attaching the stator cover 300 to the stator housing 206 or for attaching the bracket to the stator housing 206, except that the cover flanges 532, 514 cannot be welded to the stator housing 206 because the cover flanges 532, 514 are non-metallic. It should be noted that in Figure 5A As shown in Figure 10, the stator coil 208 is wound around the magnetic core 510 inside the stator housing 206. The stator coil 208 can be a stacked iron core 208.

[0055] For purposes of illustration and description, the foregoing description of embodiments of the invention has been presented. Each page of this submission and all contents thereon (however characterized, identified, or numbered) are considered an essential part of this application for all purposes, regardless of their form or placement within the application. This specification is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Numerous modifications and variations are possible according to this disclosure.

[0056] Although this application is shown in a limited number of forms, the scope of this disclosure is not limited to these forms but is subject to various changes and modifications. This application does not expressly describe all possible combinations of features falling within the scope of this disclosure. Features disclosed herein for various embodiments are generally interchangeable and combined into any non-contradictory combination without departing from the scope of this disclosure. Specifically, unless the dependent claims are logically incompatible with each other, the limitations given in the following dependent claims may be combined with their corresponding independent claims in any number and in any order without departing from the scope of this disclosure.

Claims

1. An integrated motor pump module (IMP) or an integrated motor turbine module (IMT), comprising: A module housing configured to allow fluid to flow from its input end to its output end; A stator housing, which is housed within the module housing and fixed to the module housing; A shaft that extends axially toward the proximal side from the stator housing; An impeller, the impeller being capable of rotating together with the shaft or rotating about the shaft; A plurality of permanent magnets are fixed to the distal side of the impeller and configured to pass near the proximal side of the stator housing when the impeller rotates about the shaft. A plurality of stator coils are housed within the stator housing and configured to approach the permanent magnet as the permanent magnet passes near the proximal side of the stator housing, the permanent magnet and the stator coils being axially separated by a rotor-stator gap; as well as A non-conductive stator cover is located within the rotor-stator gap, the stator cover is fixed to the stator housing and forms a cover seal with the stator housing, the cover seal being configured to prevent process fluids from entering the interior of the stator housing.

2. The IMP or IMT according to claim 1, wherein, The cover seal includes at least one gasket located between the stator cover and the stator housing.

3. The IMP or IMT according to claim 1 or claim 2, wherein, The stator housing extends around the axis, and the stator cover is configured as an annular disk.

4. The IMP or IMT according to claim 3, wherein, The cover seal includes an inner gasket radially adjacent to the inner edge of the annular stator cover and an outer gasket radially adjacent to the outer edge of the annular stator cover.

5. The IMP or IMT according to claim 3 or claim 4 further includes a pair of supports configured to radially overlap with the inner and outer peripheries of the stator cover, respectively, the supports being fixed to the stator housing and configured to press the stator cover against the stator housing.

6. The IMP or IMT according to claim 5, wherein, The bracket is attached to the stator housing by at least one of welding and adhesive attachment.

7. The IMP or IMT according to claim 5 or claim 6, wherein, The bracket includes a bracket flange that extends distally from the radially inner and outer surfaces and the radially outer outer surface of the stator housing.

8. The IMP or IMP according to claim 7, wherein, The bracket flange and the stator housing form an interference fit.

9. The IMP or IMT according to any one of claims 5 to 8, wherein: The support flange includes a radial protrusion that extends into a recess disposed in the stator housing; or The stator housing includes a radial protrusion that extends into a recess disposed in the support flange.

10. The IMP or IMT according to claim 7, wherein, The bracket flange is welded to the stator housing.

11. The IMP or IMT according to claim 10, wherein, The bracket flange is welded to the stator housing by electron beam welding.

12. The IMP or IMT according to claim 7, wherein, The bracket flange is attached to the stator housing by a positioning screw.

13. The IMP or IMT according to any one of claims 1-4, wherein, The stator cover is directly fixed to the stator housing.

14. The IMP or IMT according to claim 13, wherein, The stator cover is directly fixed to the stator housing by adhesive.

15. The IMP or IMT according to claim 14, wherein, The cover seal is formed by the adhesive.

16. The IMP or IMT according to any one of claims 13-15, wherein: The stator housing extends about the axis; The stator cover is configured as an annular disk; and The stator cover includes a cover flange that extends distally adjacent to the radially inner and outer surfaces and the radially outer outer surface of the stator housing.

17. The IMP or IMT according to claim 16, wherein, The cover flange forms an interference fit with the stator housing.

18. The IMP or IMT according to claim 16, wherein, The cover flange is attached to the stator housing by an adhesive.

19. The IMP or IMT according to any one of claims 16-18, wherein: The cover flange includes a radial protrusion that extends into a recess disposed in the stator housing; or The stator housing includes a radial protrusion that extends into a recess provided in the cover flange.

20. The IMP or IMT according to claim 16, wherein, The cover flange is attached to the stator housing by a positioning screw.

Images