Device and method for impregnating a stator for an electric motor

The device and method simplify and expedite the impregnation process by using a container with terminals for electrical heating and agent management, addressing inefficiencies in existing stator impregnation methods.

WO2025140813A1PCT designated stage expired Publication Date: 2025-07-03SEW EURODRIVE GMBH & CO KG
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Patent Information

Application Number
PCT/EP2024/083543
Authority / Receiving Office
WO · WO
Patent Type
Applications
Current Assignee / Owner
Priority Date
2024-03-06
Filing Date
2024-11-26
Publication Date
2025-07-03

AI Technical Summary

Technical Problem

Existing methods for impregnating stators in electric motors are complex, costly, and time-consuming, lacking a simple and efficient means to apply and cure a liquid impregnating agent effectively.

Method used

A device and method involving a container with input and output terminals for connecting stator windings to an electrical power source, allowing current flow to heat the stator and reduce impregnating agent viscosity, combined with a tank for agent conveyance and drainage, facilitating easy and quick impregnation and curing.

Benefits of technology

Enables simple, cost-effective, and rapid impregnation of stators by heating the stator to controlled temperatures for optimal impregnating agent application and curing, enhancing mechanical and electrical protection.

✦ Generated by Eureka AI based on patent content.

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    Figure EP2024083543_03072025_PF_FP_ABST
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Abstract

A device according to the invention for impregnating a stator (50) for an electric motor comprises a container (30) for receiving at least one stator (50) to be impregnated, wherein the container (30) is designed to receive a liquid impregnating agent, a plurality of input terminals (14, 15, 16), in particular exactly three input terminals (14, 15, 16), for connecting input lines (54, 55, 56) of windings of a stator (50) to be impregnated, and a plurality of output terminals (41, 42, 43), in particular exactly three output terminals (41, 42, 43), for connecting output lines (51, 52, 53) of windings of a stator (50) to be impregnated. A method according to the invention for impregnating a stator (50) for an electric motor comprises the following steps: inserting a stator (50) to be impregnated into the container (30); connecting the windings of the stator (50) to an electrical energy source; heating the stator (50) by means of a current flow through the windings during a preheating period; filling the container (30) with an impregnating agent; leaving the stator (50) in the impregnating agent as further current flow through the windings takes place during an impregnating period; discharging excess impregnating agent from the container (30); hardening the impregnating agent located on the windings as further current flow through the windings takes place during a hardening period; releasing the windings of the stator (50) from the electrical energy source; removing the impregnated stator (50) from the container (30).
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Description

[0001] Device and method for impregnating a stator for an electric motor

[0002] Description:

[0003] The invention relates to a device and a method for impregnating a stator for an electric motor with a liquid impregnating agent.

[0004] DE 102023 000 728 A1 discloses an electric motor with a stator. The stator comprises a plurality of stator windings. Connecting wires of the stator windings protrude from the winding heads of the stator windings. The electric motor also comprises a rotor that is rotatable about an axis of rotation relative to the stator.

[0005] The stator windings must be mechanically and electrically strengthened and protected against chemical and electrical influences. For this purpose, a liquid impregnating agent, such as a resin or a resin-hardener mixture, is applied to the windings and then allowed to cure. To apply the impregnating agent, it is known to sprinkle the windings with the impregnating agent or to immerse the windings in the impregnating agent.

[0006] From DE 103 60285 A1 a device for introducing impregnating agents into electrical components is known.

[0007] A device for painting electrical windings is known from JP H07-39 120 A.

[0008] From DE 196 31 474 01 a device for impregnating electrical windings is known.

[0009] From DE 102011 056 986 A1 a conductor connection terminal is known which comprises an insulating housing and a busbar.

[0010] DE 202015 102 597 U1 discloses a cable connector having an insulating housing. The invention is based on the object of specifying a device and a method for impregnating a stator for an electric motor.

[0011] The object is achieved by a device for impregnating a stator for an electric motor having the features specified in claim 1. Advantageous embodiments and further developments are the subject of the subclaims. The object is also achieved by a method for impregnating a stator for an electric motor having the features specified in claim 10.

[0012] A device according to the invention for impregnating a stator for an electric motor comprises a container for accommodating at least one stator to be impregnated, wherein the container is designed to hold a liquid impregnating agent. The device also comprises a plurality of input terminals, in particular exactly three input terminals, for connecting input lines of windings of a stator to be impregnated. The device also comprises a plurality of output terminals, in particular exactly three output terminals, for connecting output lines of windings of a stator to be impregnated.

[0013] The input and output terminals allow the windings of a stator to be impregnated to be connected to an electrical power source. An electrical power source connected to the windings enables a current to flow through the windings, thus heating the stator. At elevated temperatures, the viscosity of the impregnating agent decreases, and the impregnating agent flows around the stator windings. The device according to the invention thus makes impregnating a stator relatively simple, cost-effective, and quick.

[0014] According to an advantageous embodiment of the invention, the container is cuboid-shaped and has a base plate, a first side wall, a second side wall, a first end wall, and a second end wall. The side walls are arranged opposite one another, and the end walls are arranged opposite one another. The container thus has a relatively simple structure.

[0015] According to an advantageous embodiment of the invention, the device comprises a terminal block having the output terminals. The output terminals of the terminal block are electrically connected to one another. By connecting the output lines of the windings of the stator to be impregnated, a star point is thus formed.

[0016] According to an advantageous embodiment of the invention, the device comprises a plurality of clamping units, each of which has one of the input terminals. The input terminals of the clamping units are electrically isolated from one another. Thus, a multi-phase electrical energy source can be connected.

[0017] According to an advantageous embodiment of the invention, the clamping units each have a contact point for connecting an electrical power source. The contact point of each clamping unit is electrically connected to the input terminal of the clamping unit.

[0018] According to an advantageous embodiment of the invention, the device comprises an electrical energy source, in particular a three-phase energy source, and the energy source has a plurality of supply lines, in particular exactly three supply lines. Each of the supply lines is electrically connected to a contact point. The electrical energy source connected to the contact points causes a current to flow through the windings and thus heats the stator.

[0019] According to an advantageous embodiment of the invention, the clamping units are attached to a wall of the container. The clamping units extend through the wall of the container, and the input terminals are each arranged on a side of the wall opposite the contact points. Thus, the electrical energy source can be connected to the contact points outside the container.

[0020] According to an advantageous embodiment of the invention, the container comprises a drain for draining the liquid impregnating agent. Thus, excess impregnating agent can be drained from the container after impregnation before the stator is removed from the container.

[0021] According to an advantageous embodiment of the invention, the device comprises a tank for storing the liquid impregnating agent. The tank is hydraulically connected to the container in such a way that impregnating agent can be conveyed from the tank to the container and from the container to the tank. Thus, the impregnating agent can be easily fed into the container before impregnation begins, and excess impregnating agent can be easily drained from the container after impregnation before the stator is removed from the container.

[0022] A method according to the invention for impregnating a stator for an electric motor with a device according to the invention comprises the following steps:

[0023] Inserting a stator to be impregnated into the container;

[0024] Connecting the stator windings to an electrical energy source;

[0025] Heating the stator by a current flow through the windings during a preheating period;

[0026] Pouring a waterproofing agent into the container;

[0027] Leaving the stator in the impregnating agent with continued current flow through the windings for an impregnation period;

[0028] Draining excess impregnating agent from the container;

[0029] Hardening of the impregnating agent on the windings with further current flow through the windings during a hardening period;

[0030] Disconnecting the stator windings from the electrical energy source;

[0031] Removing the impregnated stator from the container.

[0032] By means of the method according to the invention, the impregnation of a stator for an electric motor can be carried out relatively simply, inexpensively and in a short time.

[0033] Before the stator to be impregnated is inserted into the container, the supply lines of the electrical power source are each electrically connected to a contact point. After the stator is inserted into the container, the input lines of the stator windings are each connected to an input terminal. Likewise, the output lines of the stator windings are each connected to an output terminal. In this way, the stator windings are connected to the electrical power source.

[0034] After the electrical power source is switched on, a current flows from each phase of the electrical power source through one of the windings to the star point of the stator. The flowing current is regulated such that the stator is heated to a temperature of approximately 130°C during the preheating period. The preheating period is, for example, between ten and twenty minutes. The impregnating agent is then poured into the container until the stator is covered with the impregnating agent. The stator is left immersed in the impregnating agent during the impregnation period, while current continues to flow through the windings. The impregnation period is, for example, five minutes.

[0035] After the impregnation period, excess impregnating agent is drained from the container. The draining time for the impregnating agent is, for example, ten minutes. The flowing current is then regulated so that the stator is heated to a temperature of approximately 160°C during the curing period. The curing period is, for example, twenty-five minutes.

[0036] The electrical power source is then switched off. The input leads of the stator windings are disconnected from the input terminals. Likewise, the output leads of the stator windings are disconnected from the output terminals. This disconnects the stator windings from the electrical power source.

[0037] For example, the impregnated stator remains in the container for a while to cool down. Then, the impregnated stator is removed from the container.

[0038] The invention is not limited to the combination of features in the claims. Further possible combinations of claims and / or individual claim features and / or features of the description and / or the figures will become apparent to those skilled in the art, particularly from the problem and / or the problem posed by comparison with the prior art.

[0039] The invention will now be explained in more detail with reference to the accompanying drawings. The invention is not limited to the exemplary embodiments shown in the drawings. The drawings only represent the subject matter of the invention schematically. They show:

[0040] Figure 1 : Device for impregnating a stator,

[0041] Figure 2: an enlarged view of the terminal block and

[0042] Figure 3: an enlarged view of the clamping units.

[0043] Figure 1 shows a device for impregnating a stator 50 for an electric motor. The device comprises a container 30 for accommodating a stator 50 to be impregnated. The stator 50 is located in the container 30. The container 30 is also designed to hold a liquid impregnating agent (not shown here).

[0044] The container 30 is cuboid-shaped. The container 30 has a base plate 31, a first side wall 33, a second side wall 34, a first end wall 35, and a second end wall 36. The side walls 33, 34 are arranged opposite one another, and the end walls 35, 36 are arranged opposite one another. The base plate 31, the side walls 33, 34, and the end walls 35, 36 enclose a trough-like receiving area within the container 30, which serves to accommodate the stator 50 and the impregnating agent. A cover side opposite the base plate 31 is open.

[0045] The stator 50 has a first winding, a second winding, and a third winding. The windings are wound from electrically conductive wires. The wires are coated, for example, with an insulating varnish layer. Each of the windings has an input line 54, 55, 56 and an output line 51, 52, 53. The windings are arranged concentrically around a central axis of the stator 50.

[0046] The device comprises a terminal block 40. The output lines 51, 52, 53 of the windings of the stator 50 are electrically connected to the terminal block 40. The terminal block 40 electrically forms a star point of the stator 50.

[0047] The device comprises a first clamping unit 11, a second clamping unit 12, and a third clamping unit 13. The first clamping unit 11 has a first contact point 17. The second clamping unit 12 has a second contact point 18. The third clamping unit 13 has a third contact point 19.

[0048] The clamping units 11, 12, 13 are attached to the first side wall 33 of the container 30. The clamping units 11, 12, 13 extend through the first side wall 33 of the container 30. The contact points 17, 18, 19 are arranged outside the receiving area of ​​the container 30.

[0049] The device comprises a three-phase electrical power source (not shown here). The power source has three supply lines. Each of the supply lines is electrically connected to a contact point 17, 18, 19. The clamping units 11, 12, 13 are each electrically connected to an input line 54, 55, 56.

[0050] The device comprises a tank for storing the liquid impregnating agent. The tank is hydraulically connected to the container 30 such that impregnating agent can be conveyed from the tank to the container 30 and from the container 30 to the tank. For this purpose, the device comprises, for example, a pump. Alternatively or additionally, the container 30 comprises a drain for draining the liquid impregnating agent.

[0051] Figure 2 shows an enlarged view of the terminal block 40 of the device shown in Figure 1. The terminal block 40 has a first output terminal 41, a second output terminal 42, and a third output terminal 43. Thus, the device comprises three output terminals 41, 42, 43 for connecting the output lines 51, 52, 53 of the windings of the stator 50 to be impregnated.

[0052] A first output line 51 of the stator 50 is connected to the first output terminal 41. A second output line 52 of the stator 50 is connected to the second output terminal 42. A third output line 53 of the stator 50 is connected to the third output terminal 43.

[0053] The output terminals 41, 42, 43 of the terminal block 40 are electrically connected to one another. Thus, the output lines 51, 52, 53 of the stator 50 are also electrically connected to one another. Thus, the terminal block 40 electrically forms the aforementioned star point of the stator 50. Figure 3 shows an enlarged view of the clamping units 11, 12, 13 of the device shown in Figure 1. The first clamping unit 11 has a first input terminal 14. The second clamping unit 12 has a second input terminal 15. The third clamping unit 13 has a third input terminal 16. Thus, the device comprises three input terminals 14, 15, 16 for connecting the input lines 54, 55, 56 of the windings of the stator 50 to be impregnated.

[0054] A first input line 54 of the stator 50 is connected to the first input terminal 14. A second input line 55 of the stator 50 is connected to the second input terminal 15. A third input line 56 of the stator 50 is connected to the third input terminal 16.

[0055] The first contact point 17 is electrically connected to the first input terminal 14. The second contact point 18 is electrically connected to the second input terminal 15. The third contact point 19 is electrically connected to the third input terminal 16. The input terminals 14, 15, and 16 of the clamping units 11, 12, and 13 are electrically isolated from each other. Thus, the contact points 17, 18, and 19 are also electrically isolated from each other.

[0056] A first phase of the electrical energy source is thus electrically connected to the first input line 54 of the stator 50 via a supply line, the first contact point 17, and the first input terminal 14. A second phase of the electrical energy source is thus electrically connected to the second input line 55 of the stator 50 via a supply line, the second contact point 18, and the second input terminal 15. A third phase of the electrical energy source is thus electrically connected to the third input line 56 of the stator 50 via a supply line, the third contact point 19, and the third input terminal 16.

[0057] Thus, a current flows from the first phase of the electrical energy source through the first winding to the star point of the stator 50. Likewise, a current flows from the second phase of the electrical energy source through the second winding to the star point of the stator 50. Likewise, a current flows from the third phase of the electrical energy source through the third winding to the star point of the stator 50. List of reference symbols

[0058] 11 first clamping unit

[0059] 12 second clamping unit

[0060] 13 third clamping unit

[0061] 14 first input terminal

[0062] 15 second input terminal

[0063] 16 third input terminal

[0064] 17 first contact point

[0065] 18 second contact point

[0066] 19 third contact point

[0067] 30 containers

[0068] 31 Base plate

[0069] 33 first side wall

[0070] 34 second side wall

[0071] 35 first front wall

[0072] 36 second end wall

[0073] 40 terminal block

[0074] 41 first output terminal

[0075] 42 second output terminal

[0076] 43 third output terminal

[0077] 50 Stator

[0078] 51 first output line

[0079] 52 second output line

[0080] 53 third output line

[0081] 54 first input line

[0082] 55 second input line

[0083] 56 third input line

Claims

Patent claims:

1. Device for impregnating a stator (50) for an electric motor, comprising a container (30) for receiving at least one stator (50) to be impregnated, wherein the container (30) is designed to receive a liquid impregnating agent, a plurality of input terminals (14, 15, 16), in particular exactly three input terminals (14, 15, 16), for connecting input lines (54, 55, 56) of windings of a stator (50) to be impregnated and a plurality of output terminals (41, 42, 43), in particular exactly three output terminals (41, 42, 43), for connecting output lines (51, 52, 53) of windings of a stator (50) to be impregnated.

2. Device according to claim 1, characterized in that the container (30) is cuboid-shaped and has a base plate (31), a first side wall (33), a second side wall (34), a first end wall (35) and a second end wall (36), and that the side walls (33, 34) are arranged opposite one another, and that the end walls (35, 36) are arranged opposite one another.

3. Device according to one of the preceding claims, characterized in that the device comprises a terminal block (40) which has the output terminals (41, 42, 43), and that the output terminals (41, 42, 43) of the terminal block (40) are electrically connected to one another.

4. Device according to one of the preceding claims, characterized in that the device comprises a plurality of clamping units (11, 12, 13), each having one of the input terminals (14, 15, 16), and in that the input terminals (14, 15, 16) of the clamping units (11, 12, 13) are electrically insulated from one another.

5. Device according to claim 4, characterized in that the clamping units (11, 12, 13) each have a contact point (17, 18, 19) for connecting an electrical energy source, and in that the contact point (17, 18, 19) of a clamping unit (11, 12, 13) is electrically connected to the input terminal (14, 15, 16) of the clamping unit (11, 12, 13).

6. Device according to claim 5, characterized in that the device comprises an electrical energy source, in particular a three-phase energy source, and in that the energy source has a plurality of supply lines, in particular exactly three supply lines, and in that each of the supply lines is electrically connected to a respective contact point (17, 18, 19).

7. Device according to one of claims 4 to 6, characterized in that the clamping units (11, 12, 13) are fastened to a wall (33, 34, 35, 36) of the container (30), and in that the clamping units (11, 12, 13) pass through the wall (33, 34, 35, 36) of the container (30), and in that the input terminals (14, 15, 16) are each arranged on a side of the wall (33, 34, 35, 36) opposite the contact points (17, 18, 19).

8. Device according to one of the preceding claims, characterized in that the container (30) comprises a drain for draining the liquid impregnating agent.

9. Device according to one of the preceding claims, characterized in that the device comprises a tank for storing the liquid impregnating agent, and that the tank is hydraulically connected to the container (30) in such a way that impregnating agent can be conveyed from the tank to the container (30) and from the container (30) to the tank.

10. A method for impregnating a stator (50) for an electric motor with a device according to one of the preceding claims, comprising the following steps: Inserting a stator (50) to be impregnated into the container (30); Connecting the windings of the stator (50) to an electrical energy source; Heating the stator (50) by a current flow through the windings during a preheating period; Pouring an impregnating agent into the container (30); Leaving the stator (50) in the impregnating agent with continued current flow through the windings for an impregnation period; Draining excess impregnating agent from the container (30); Hardening of the impregnating agent on the windings with further current flow through the windings during a hardening period; Disconnecting the windings of the stator (50) from the electrical energy source; removing the impregnated stator (50) from the container (30).

Citation Information

Patent Citations

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    DE102011056986A1

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    DE10360285A1

  • Line connection

    DE202015102597U1

  • Method and apparatus for varnish treatment of winding

    JP1995039120A