Method for sealing a slot closure wedge on an oil-cooled stator and slot closure wedge

Abstract

The invention relates to a method for sealing a slot closure wedge (20) on an oil-cooled stator (1) with direct slot cooling, in which a sealant (22) is introduced from the end face (20a) of the slot closure wedge (20) into at least one longitudinal distribution opening (24) of the installed slot closure wedge (20), the sealant (22) is guided from the at least one longitudinal distribution opening (24) to at least one transverse distribution opening (26) of the slot closure wedge (20), wherein, to seal the slot closure wedge (20) against the stator (1), the sealant (22) is introduced from the at least one transverse distribution opening (26) into a sealing groove (21) at the edges (20b) of the wedge. The invention further relates to such a slot closure wedge (20).

Description

[0001] The invention relates to a method for sealing a slot closure wedge on an oil-cooled stator according to the preamble of patent claim 1. Furthermore, the invention relates to such a slot closure wedge.

[0002] In the pre-development and development of electrical machines, heat dissipation and cooling are crucial factors for performance and service life. Oil-cooled stators with direct slot cooling are a well-known state-of-the-art solution for controlling operating temperatures. Accordingly, the development of high-performance stator cooling using oil directly on the conductors is being pursued. However, sealing the oil chamber near the conductors from the air gap presents a technical challenge. Inadequate sealing can lead to oil ingress, which impairs the machine's efficiency.

[0003] DE 10 2020 215 736 A1 already discloses an electric machine comprising a stator and a rotor, wherein the rotor and / or the stator has teeth, wherein the teeth have windings, and wherein a groove is formed between each pair of circumferentially adjacent teeth, wherein at least one wedge-shaped slot closure element is arranged in the groove. It is also disclosed that the slot closure element has at least one guide, in particular a channel, for a hardenable medium.

[0004] The object of the invention is to provide a possibility to improve the sealing of oil-cooled stators with direct slot cooling.

[0005] This object is achieved according to the invention by a method for sealing a slot sealing wedge on an oil-cooled stator having the features of patent claim 1 and by means of a slot sealing wedge according to the invention. Advantageous embodiments of the invention are the subject of the dependent patent claims and the description.

[0006] One aspect of the invention relates to a method for sealing a slot closure wedge on an oil-cooled stator with direct slot cooling, in which a sealing compound is introduced from the end face of the slot closure wedge into at least one longitudinal distribution opening of the installed closure wedge. Furthermore, the sealing compound is directed from the at least one longitudinal distribution opening to at least one transverse distribution opening of the closure wedge.

[0007] To achieve the object of the invention, it is provided that, to seal the slot closure wedge against the stator or stator body, the sealing compound is introduced from the at least one transverse distribution opening into a sealing groove or into a gap at the edges of the wedge. Accordingly, the sealing of oil-cooled stators with direct slot cooling should be enabled. Sealing is necessary, in particular, to prevent oil from penetrating the air gap. In other words, a method for sealing slot closure wedges and slot insulation bodies using a special sealing compound is described. This method contributes to ensuring a particularly oil-tight connection between the various components.

[0008] The basic principle of the described method for sealing slot closure wedges and slot insulation bodies is therefore based on the use of a special sealing compound. This sealing compound is applied to the end face(s) of the slot closure wedges and directed via longitudinal and transverse distribution openings to the spaces to be sealed between the slot closure wedges and the slot insulation bodies. The sealing compound is thus applied, for example, to the end face of the slot closure wedge. This can be achieved using various methods, including inserting the sealing compound into the slot closure wedges using special tools or automated processes. This application therefore enables a particularly even distribution of the sealing compound. The slot closure wedges comprise longitudinal and transverse distribution openings, which are designed as channels to direct the sealing compound from the end face of the wedge to the spaces to be sealed.The longitudinal distribution openings extend along the length of the wedge, while the transverse distribution openings are arranged laterally.

[0009] The actual sealing is achieved by introducing the sealing compound from the transverse distribution openings into a sealing groove or into the gap at the edges of the wedge. This creates an effective sealing barrier that prevents oil from penetrating the air gap. The sealing compound completely fills the gaps between the slot closure wedges and the slot insulation bodies, thus forming the intended oil-tight connection. The described method for sealing slot closure wedges and slot insulation bodies offers a number of advantages, for example, the efficiency of the electrical machine is improved by preventing oil from penetrating the air gap.

[0010] In an advantageous embodiment of the invention, the sealant is directed into a plurality of transverse distribution openings. These transverse distribution openings are arranged, distributed, or positioned evenly or unevenly in the area of ​​the slot closure wedges and are also designed as controlled channels for the distribution of the sealant. This predetermined arrangement enables even distribution and thus sealing, preventing the occurrence of leaks. It also enables efficient use of the sealant, as it is directed or directed precisely where it is needed without clogging.

[0011] In another advantageous embodiment of the invention, the sealing compound is directed from the at least one longitudinal distribution opening to at least one diagonal distribution opening. These diagonal distribution openings are specifically designed to direct the sealing compound at a defined angle relative to the at least one transverse distribution opening and thus to the areas to be sealed. This allows for a further option for positioning the sealing compound along the edges of the slot closure wedges and slot insulation bodies.

[0012] In another advantageous embodiment of the invention, sealing compound is introduced into a plurality of longitudinal distribution openings. These longitudinal distribution openings run, for example, parallel along the length of the slot closure wedges and enable a uniform distribution of the sealing compound over the entire circumference of the slot closure wedges, thereby allowing more sealing compound to be distributed in a shorter time.

[0013] Finally, a further advantageous embodiment of this invention provides for any excess sealant to be expelled through the sealing groove. This feature not only allows for a predetermined dosage of sealant but also minimizes excess, with the return of the excess sealant enabling a clean seal along the groove closure wedges.

[0014] A further aspect of the invention relates to a slot sealing wedge for slot insulation on an oil-cooled stator with direct slot cooling. To seal the slot sealing wedge against the stator or stator body, the sealing compound can be introduced from the at least one transverse distribution opening into a sealing groove at the edges of the wedge. The slot sealing wedge utilizes the transverse distribution openings incorporated into the slot sealing wedge and thus associated with or integrated into the slot sealing wedge. These transverse distribution openings are thus provided as controlled channels for distributing the sealing compound. The positioning of these openings is designed such that the sealing compound is directed specifically into the sealing groove at the edges of the wedge. This enables uniform sealing along the contact surfaces between the wedge and the stator body.The main function is therefore to effectively seal the slot closure wedge against the stator body. This is achieved by the targeted introduction of the sealing compound into the sealing groove. The sealing compound fills all cavities and irregularities in this area, creating a tight and reliable seal.

[0015] The sealing of the slot-locking wedge against the stator body, as previously described in the process, serves the primary purpose of preventing oil from penetrating the air gap between the stator components. Efficient sealing ensures that the oil cooling system can perform its task with high quality, particularly by maintaining the desired temperature control. Oil penetration could impair the efficiency of the electric machine and lead to unwanted contamination in the surrounding area.

[0016] In an advantageous embodiment of the invention, a plurality of transverse distribution openings are arranged within a structure of the slot closure wedge. These transverse distribution openings are thus arranged within the slot closure wedge and serve as channels for the particularly rapid distribution of the sealing compound. The predetermined arrangement of these openings ensures that the sealing compound is evenly distributed into the sealing groove at various points along the edges of the wedge. This enables faster and more reliable sealing.

[0017] In another advantageous embodiment of the invention, a plurality of longitudinal distribution openings are arranged within a structure of the slot closure wedge. Here, too, the idea of ​​faster sealing is pursued, with these longitudinal distribution openings extending, for example, parallel to one another and along the length of the slot closure wedge and being usable as channels for the uniform distribution of the sealing compound.

[0018] In another advantageous embodiment of the invention, the sealing groove has a height that differs from the cross-section of the longitudinal distribution opening and / or has a width that is smaller than the height. These possible variations in the geometry of the sealing groove enable control of the sealant as well as adjustment of the sealing thickness and sealing speed. The different heights and widths of the sealing groove allow for targeted distribution of the sealant along the edges of the wedge and ensure a predetermined seal.

[0019] Finally, in another advantageous embodiment of the invention, the sealing groove has at least one outlet opening for discharging an excess amount of sealant. The outlet openings thus allow an excess amount of sealant to be discharged from the sealing groove, ensuring efficient use of the sealing material and enabling a clean seal along the slot closure wedges and slot insulation bodies. Furthermore, the outlet signals that the sealant is evenly distributed.

[0020] The method and / or the slot-locking wedge can be adapted to various applications and geometries. Furthermore, the method and / or the slot-locking wedge offer an effective solution for preventing oil ingress and improving the performance and service life of electrical machines.

[0021] Further features of the invention emerge from the claims, the figures, and the description of the figures. The features and combinations of features mentioned above in the description, as well as the features and combinations of features mentioned below in the description of the figures and / or shown alone in the figures, can be used not only in the respective specified combination, but also in other combinations or on their own.

[0022] The invention will now be explained in more detail using a preferred embodiment and with reference to the drawings. They show: Fig. 1 shows a cross section of a possible embodiment of a partial region of a stator to illustrate a method according to the invention for sealing a slot closure wedge on an oil-cooled stator; Fig. 2 a perspective view of the slot closure wedge to illustrate a path of the sealing compound after insertion; Fig. 3 a further perspective view of the slot closure wedge to illustrate the sizes and dimensions of the openings and sealing grooves; and Fig. 4 a picture diagram of the distribution of the sealant with a time dependence.

[0023] In the figures, identical and functionally identical elements are provided with the same reference numerals.

[0024] Fig. Figure 1 shows a cross-section of a possible embodiment of a portion of a stator 10 to illustrate a method according to the invention for sealing a slot closure wedge 20 on a cooled or oil-cooled stator 1 with direct slot cooling. In particular, the stator 1 is shown with a stator core 10, a copper conductor 12, a lacquer layer 14, and a slot insulation 16. A cooling oil 18 and the slot closure wedge 20 are also shown.

[0025] In particular, an enlargement of the slot closure wedge 20 is shown, with the respective sealing grooves 21 on respective sides or on respective edges 20b, wherein a longitudinal distribution opening 24 is shown on the end face 20a of the slot closure wedge 20. A sealing compound 22 is shown in the longitudinal distribution opening 24 and in the respective sealing grooves 21 on the edges 20b.

[0026] In particular, a method for sealing a slot closure wedge 20 on the oil-cooled stator 1 with direct slot cooling is provided here, in which the sealing compound 22 is introduced from the end face 20a of the slot closure wedge 20 into the longitudinal distribution opening 24 of the installed slot closure wedge 20. The sealing compound 22 is thus guided from the at least one longitudinal distribution opening 24 to at least one transverse distribution opening 26 (not shown) of the slot closure wedge 20. This means that the sealing compound 22 is introduced through the longitudinal distribution opening 24 and thus introduced into the slot closure wedge 20. The sealing compound 22 is then passed into respective transverse distribution openings 26 along the longitudinal distribution opening 24 and exits from these transverse distribution openings into the sealing groove 21.The longitudinal distribution opening 24 and the transverse distribution opening 26 are respective channels that extend inside the slot closure wedge 20 and thus guide the sealing compound 22 to the sealing grooves 21.

[0027] In contrast to the transverse distribution opening 26, the oblique distribution opening 28 provides for an oblique or angled forwarding of the sealing compound 22 relative to the longitudinal extension direction of the longitudinal distribution opening 24. This makes it possible, in particular, to provide different areas or other channel designs within the slot closure wedge 20. Depending on the requirements, it should be possible to guide the sealing compound 22 as precisely as possible within the slot closure wedge 22 and then into the respective sealing grooves 21, so that the cooling oil 18 is sealed off from the surroundings of the stator 1.

[0028] Furthermore, it is also possible to allow an excess quantity 30 of the sealing compound 22 to flow out again through the sealing groove 21, so that the even distribution of the sealing compound 22 is particularly efficient. Thus, the excess quantities 30 or the excess of sealing compound 22 can flow out again and be removed.

[0029] In particular, a slot closure wedge 20 for slot insulation 16 on an oil-cooled stator 1 with direct slot cooling is described here, wherein, for sealing the slot closure wedge 20 against the stator 1, the sealing compound 22 can be introduced from the at least one transverse distribution opening 26 or from arranged oblique distribution openings 28 into one of the sealing grooves 21 on the edges 20b of the slot closure wedge 20 or into both sealing grooves 21, depending on the design.

[0030] It is also possible to arrange a plurality of transverse distribution openings 26 within the structure of the slot closure wedge 20 and to use a plurality of longitudinal distribution openings 24 within the structure of the slot closure wedge 20, wherein the plurality of longitudinal distribution openings 24 can be arranged, for example, parallel to one another in the longitudinal extension direction of the slot closure wedge 20.

[0031] The Fig. 2 shows a perspective view of the emergency closure wedge 20 to illustrate a path of the sealing compound 22 after insertion into the longitudinal distribution opening 24. Here, the longitudinal distribution opening 24 is depicted as a channel, and thus the longitudinal distribution opening 24 extends in the longitudinal direction of the emergency closure wedge 20. This makes it possible to arrange respective transverse distribution openings 26 in the longitudinal direction of the longitudinal distribution opening 24, which lead the sealing compound 22 as channels on the respective sides to the respective sealing grooves 21.

[0032] The sealing compound 22 is shown in particular as arrows, which is guided through the longitudinal distribution opening 24 into the emergency closure wedge 20, then guided through the transverse distribution opening 26 to the sealing grooves 21 and then distributed along the sealing grooves 21.

[0033] Subsequently, it is possible to discharge an excess quantity 30 of the sealing compound 22 through respective outlet openings 21a. Here, too, it is possible to arrange respective oblique distribution openings 26 at the longitudinal distribution opening 24, although these are not shown.

[0034] In particular, it is also possible to arrange a plurality of transverse distribution openings 26 along the elongated extension direction of the longitudinal distribution opening. Thus, the sealing compound 22 is introduced into the emergency closure wedge 20, which, for example, hardens after a predetermined time and thus enables sealing at the sealing grooves 21.

[0035] Fig. 3 shows a further perspective view of the slot closure wedge 20 to illustrate the sizes and dimensions of the openings and sealing grooves 21. The sealing grooves 21 are formed with a cross-section Q of the longitudinal distribution opening 24 with a different height H and / or with a width B that is smaller than the height H. Accordingly, it is possible to provide different configurations of the dimensions of the respective openings relative to the sealing groove 21, thereby enabling a faster distribution of the sealing compound 22, but also a more precise and targeted distribution. Finally, the sealing groove 21 is designed such that at least one outlet opening is arranged for discharging an excess amount 30 of the sealing compound 22. The outlet opening has the reference number 21a.

[0036] Fig.4 shows an image diagram of the distribution of the sealing compound 22 with a temporal dependence. Here, at a time T1, the sealing compound 22 is introduced into the longitudinal distribution opening 24, which initially extends only through the longitudinal distribution opening 24 and thus extends in the longitudinal direction of extension of the emergency closure wedge 20. At a second time T2, which occurs after T1, the sealing compound 22 has already progressed further, whereby the path along the longitudinal distribution opening 24 is longer and distribution through the transverse distribution opening 26 in the direction of the sealing grooves 21 has taken place. At a third time T3, the sealing compound has progressed even further, whereby a plurality of transverse distribution openings 26, which are arranged along the longitudinal direction of extension of the longitudinal distribution opening 24, have now been passed through and are distributed over a larger area of ​​the respective sealing grooves 21.At a time T4, the entire sealing compound 22 is distributed almost over the entire area of ​​the respective sealing grooves 21, whereby the sealing of the stator or the emergency closure wedge 22 against the stator 1 is almost provided. Subsequently, when the sealing compound 22 is completely distributed, an excess amount 30 of the sealing compound 22 can exit again via respective outlet openings.

[0037] In other words, the process of sealing the slot closure wedge 20 on the oil-cooled stator 1 with direct slot cooling thus proceeds in several successive temporal phases, which illustrate the progressive progress of the sealing compound distribution of the sealing compound 22. At the beginning, in the first phase or first time T1, the sealing compound 22 lies exclusively in the longitudinal distribution opening 24 of the slot closure wedge 20. At this stage, the sealing compound 22 is confined to the longitudinal distribution opening 24 and has no contact with the adjacent transverse distribution openings 26 or the sealing grooves 21.

[0038] After a certain period of time, which has elapsed after the first phase, the sealing compound reaches the transverse distribution openings 26, which represents the beginning of the second phase or the second time T2. Here, the sealing compound 22 begins to move from the longitudinal distribution opening 24 toward the sealing grooves 21. This thus marks the beginning of distribution into the surrounding channels.

[0039] In the third phase, or at the third time T3, the sealing compound 22 has passed through a plurality of transverse distribution openings 26. Now, the sealing compound 222 begins to distribute over a wider area of ​​the sealing grooves 21. The distribution extends further along the groove closure wedge 20.

[0040] Finally, in the fourth phase or at the fourth time T4, the sealing compound 22 is practically completely distributed in the sealing grooves 21. The sealing of the slot closure wedge 20 with respect to the stator 1 is almost complete. The sealing compound 22 can thus be evenly distributed. Furthermore, an excess amount 30 can escape from the respective outlet openings 21a. This enables an effective seal between the slot closure wedge 20 and the stator 1.

[0041] In summary, the invention proposes a method for sealing slot closure wedge 20 for slot insulation on an oil-cooled stator 1 with direct slot cooling. List of reference symbols 1 stator 10 stator lamination pack 12 copper conductors 14 coats of paint 16 Slot insulation 18 Cooling oil 20 slot locking wedge 21 Sealing groove 21a Exit opening 20a front side 20b margins 22 Sealant 24 Longitudinal distribution opening 26 Cross distribution opening 28 inclined distribution openings 30 excess quantity H Height B Width Q cross-section T1-T4 time points QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2020 215 736 A1

[0003]

Claims

[1] Method for sealing a slot closure wedge (20) on an oil-cooled stator (1) with direct slot cooling, in which a sealing compound (22) is introduced from the end face (20a) of the slot closure wedge (20) into at least one longitudinal distribution opening (24) of the installed slot closure wedge (20), the sealing compound (22) is guided from the at least one longitudinal distribution opening (24) to at least one transverse distribution opening (26) of the slot closure wedge (20), characterized by in that, in order to seal the slot closure wedge (20) against the stator (1), the sealing compound (22) is introduced from the at least one transverse distribution opening (26) into a sealing groove (21) at the edges (20b) of the wedge. [2] Method according to claim 1, characterized by that sealing compound (22) is fed into a plurality of transverse distribution openings (26). [3] Method according to claim 1 or 2, characterized bythat the sealing compound (22) is guided from the at least one longitudinal distribution opening (24) to at least one oblique distribution opening (28). [4] Method according to one of the preceding claims, characterized by that sealing compound (22) is introduced into a plurality of longitudinal distribution openings (24). [5] Method according to one of the preceding claims, characterized by that an excess amount (30) of the sealing compound (22) is discharged again through the sealing groove (21). [6] Slot closure wedge (20) for slot insulation (16) on an oil-cooled stator (1) with direct slot cooling, characterized by in that, in order to seal the slot closure wedge (20) against the stator (1), the sealing compound (22) can be introduced from the at least one transverse distribution opening (26) into a sealing groove (21) at the edges (20b) of the wedge. [7] Slot closure wedge (20) according to one of the preceding claims, characterized bythat a plurality of transverse distribution openings (26) are arranged within a structure of the slot closure wedge (20). [8] Slot closure wedge (20) according to one of the preceding claims, characterized by that a plurality of longitudinal distribution openings (24) are arranged within a structure of the slot closure wedge (20). [9] Slot closure wedge (20) according to one of the preceding claims, characterized by that the sealing groove (21) has a height (H) different from a cross-section (Q) of the longitudinal distribution opening (24) and / or the sealing groove (21) has a width (B) smaller than the height (H). [10] Slot closure wedge (20) according to one of the preceding claims, characterized by that the sealing groove (21) has at least one outlet opening (21a) for the discharge of an excess quantity (30) of the sealing compound (22).

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