Stator for an electric motor

Abstract

Stator for an electric motor (30), in particular for an EC motor, comprising a stator housing (12) in which a stator winding (16) is received, a support body (18) formed by overmolding a laminated core (26) with an insulating plastic material on which the stator winding (16) is held, the support body (18) projecting from the laminated core (26) of the stator (10) at both axial ends and forming receptacles (28) for the stator winding (16) around which the stator winding (16) is wound, and a temperature sensor (22) for temperature monitoring, which is held in a recess (20) of the support body (18), characterized in that the recess (20) is provided within a receptacle (28) and the temperature sensor (22) is inserted into the recess (20) and is fixed there between the stator winding (16) and the support body (18) by means of a thermally conductive paste.

Description

[0001] The invention relates to a stator for an electric motor, in particular for an EC motor, comprising a stator housing in which at least one stator winding is accommodated, a support body on which the at least one stator winding is held, and a temperature sensor for temperature monitoring.

[0002] Such a stator is known from DE 198 59 011 C1. US 2015 / 0 155 760 A1 describes an insulator with a stem section between the tooth and the stator coil, and a flange with a notch that holds a temperature sensor between the holder and the stator coil via a holder. DE 10 2010 064 051 A1 relates to a winding support part for electrical machines, in particular a winding support half, with a U-shaped base part, a winding support collar arranged at the end, positioning structures for holding connection sections of the winding wire, and a guide element for guiding the connection sections. DE 10 2007 062 059 A1 relates to a winding support with insulating material that partially encloses tooth and yoke sections of a primary part segment and electrically insulates windings of adjacent segments. This simplifies the manufacture of the primary part.JP 2010-154600A describes a temperature sensor holder comprising a mounting element for fixing it in the stator and a protective element for the wire to the connector. US 2011 / 0285220A1 describes a rotating electrical machine comprising a stator, an insulating resin sheath around the winding, a rotor with a shaft, a terminal block at the winding end, and a housing. JP 2008-136324A describes a rotating electrical machine comprising an annular stator, a coil wound around the stator teeth, a resin part for fixing the coil to the stator core, a hole in the resin part, and a temperature sensor inserted into the hole and supported by the inner surface of the resin part. JP 2003-92858A relates to a structure for mounting a temperature sensing element that detects the temperature of a motor winding to prevent a winding fire.

[0003] This design incorporates a support body surrounded by an electrically conductive stator winding and featuring a detachably attachable thermal protection element. To ensure good, thermally conductive contact between the thermal protection element and the stator winding, a sleeve-shaped receiving body made of a metallic material is permanently integrated into the stator winding. The receiving body protrudes from the stator winding at one open end, allowing the thermal protection element to be inserted into this open end after the stator winding has been installed.

[0004] This allows for reliable monitoring of the stator winding against overheating.

[0005] However, a disadvantage of this design is that the sleeve for the temperature protection element must be wound into the stator winding. This results in a complicated and expensive manufacturing process.

[0006] On the other hand, it is generally known in the prior art to directly wrap a temperature sensor in a stator winding.

[0007] This also has the disadvantages described above.

[0008] Against this background, the invention is based on the objective of disclosing a stator in which a temperature sensor for temperature monitoring is incorporated in close contact with at least one stator winding, resulting in a simple manufacturing process.

[0009] Furthermore, a suitable manufacturing process for producing such a stator should be specified.

[0010] This problem is solved according to the invention in a stator of the type mentioned at the outset by holding the temperature sensor in a recess of the support body.

[0011] The problem solved by the invention is thus resolved.

[0012] According to the invention, a recess is provided in the support body into which the temperature sensor can be inserted radially from the outside after the winding has been applied and fixed there between the at least one stator winding and the support body. Thus, the winding of the stator windings is not obstructed by the temperature sensor.

[0013] In a preferred embodiment of the invention, the support body is designed as a plastic injection molded part in which a recess for the temperature sensor is provided.

[0014] Preferably, the at least one support body protrudes from the stator's core at both axial ends, so that receptacles for the at least one stator winding are formed at both axial ends.

[0015] The temperature sensor can be inserted into the recess from the outside and fixed in place.

[0016] These measures enable simple and cost-effective mounting of the temperature sensor in the area of ​​at least one stator winding.

[0017] The stator is preferably designed as a stator for a so-called EC motor, i.e., an electronically commutated motor. EC motors have the advantage of being brushless. The rotor is set in motion by a rotating magnetic field generated by a suitable control unit in the stator.

[0018] The invention further specifies a method for manufacturing a stator for an electric motor, in particular for an EC motor, in which a support body for receiving at least one stator winding is manufactured from a plastic by an injection molding process, wherein a recess for a temperature sensor is created by a slide during injection molding, and wherein, after the application of the at least one stator winding to the support body, a temperature sensor is inserted radially from the outside into the recess and fixed between the at least one stator winding and the support body.

[0019] Manufacturing the support body using an injection molding process allows for simple and cost-effective production. The recess for the temperature sensor can be created during the injection molding process using a slide.

[0020] For this purpose, the sheet metal core is preferably overmolded with plastic, so that receptacles are formed at both axial ends of the stator, onto which the stator windings are wound.

[0021] If several predetermined positions are to be provided for the installation of one or more temperature sensors, several slides can be provided in the injection mold.

[0022] It is understood that the features of the invention mentioned above and those to be explained below can be used not only in the combinations specified, but also in other combinations or on their own, without leaving the scope of the invention.

[0023] Further features and advantages of the invention will become apparent from the following description of a preferred embodiment with reference to the drawing. The drawing shows: Fig. 1 a perspective view of a stator according to the invention for an EC motor; Fig. 2 a side view of the stator according to Fig. 1; Fig. 3 a sectional perspective view of the stator according to Fig. 1; Fig. 4 an enlarged section of the stator according to Fig. 3 in the area of ​​the temperature sensor and Fig. 5 a simplified schematic representation of an EC motor in which the stator according to the invention can be installed.

[0024] In the Fig. Figures 1 to 3 show a stator according to the invention and are collectively designated by the number 10.

[0025] The stator 10 has a stator housing 12. On the inside of the stator housing 12, a plurality of stator windings 16 are provided, each of which is wound on an associated support body 18.

[0026] As especially from Fig. As can be seen in more detail in Figure 3, the sheet metal core 26 of the stator 10 is overmolded at both its axial ends with an insulating plastic material, so that support bodies 18 with receptacles 28 at both axial ends are formed around which the stator windings 16 are wound.

[0027] In this case, a recess 20 is provided at at least one point on the support body 18, which is designed to accommodate a temperature sensor 22.

[0028] As can be seen from the enlarged illustration according to Fig. As can be seen in Figure 4, the temperature sensor 22, with its sensor head, can be inserted directly into the recess 20 after the stator windings 16 have been applied and is preferably fixed therein by means of a thermally conductive paste (not shown). The associated connecting leads of the temperature sensor 22 are connected to a control circuit with which the electric motor is controlled and monitored.

[0029] In Fig.Figure 5 is a simplified representation of an EC motor, designated as 30. The EC motor has a stator 10 of the type described above. A rotor 32 is rotatably mounted within the stator 10. A control circuit 36 ​​serves to control the stator in order to generate a rotating magnetic field. Only two connecting lines 34, which connect the control circuit 36 ​​to the stator 10, are shown here as an example. However, it is understood that the stator windings 16 are connected to the control circuit 36 ​​via a circuit board with at least three lines 34.

[0030] The connecting lines 24 of the temperature sensor 22 are also connected to the control unit 36.

Claims

[1] Stator for an electric motor (30), in particular for an EC motor, with a stator housing (12) in which a stator winding (16) is accommodated, with a support body (18) which is formed by overmolding a sheet metal core (26) with an insulating plastic material, on which the stator winding (16) is held, wherein the support body (18) protrudes from the sheet metal core (26) of the stator (10) at both axial ends and forms receptacles (28) for the stator winding (16), around which the stator winding (16) is wound, and with a temperature sensor (22) for temperature monitoring, which temperature sensor is held in a recess (20) of the support body (18), characterized by that the recess (20) is provided within a receptacle (28) and the temperature sensor (22) is inserted into the recess (20) and is fixed there between the stator winding (16) and the support body (18) by means of a thermally conductive paste. [2] Stator according to claim 1, characterized bythat the support body (18) is designed as a plastic injection-molded part in which a recess (20) for the temperature sensor (22) is provided. [3] Electric motor (30), in particular EC motor, with a stator (10) according to one of the preceding claims. [4] Method for producing a stator (10) for an electric motor (30), in particular for an EC motor, in which a support body (18) is produced by overmolding a sheet metal core (26) for receiving a stator winding (16) from a plastic by an injection molding process, wherein a recess (20) for a temperature sensor (22) is produced by a slider during injection molding, and wherein after the stator winding (16) has been applied to the support body (18), a temperature sensor (22) is inserted into the recess (20) and fixed between the stator winding (16) and the support body (18) by means of a thermally conductive paste, wherein to produce the support body (18) the sheet metal core (26) of the stator is overmolding so that receptacles (28) are formed at both axial ends of the stator, onto which the stator winding (16) is wound.

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