JPH0231578B2 - - Google Patents

Description

[Detailed description of the invention] Technical field of invention The present invention relates to an electric motor and a method of manufacturing the same.

Prior Art and Problems Conventionally, permanent magnet field synchronous motors and induction motors that use a laminated stator core with laminated steel plates as part of the motor jacket have been used, for example, as AC servo motors. When using these electric motors as servo motors, for example,
Particularly high mechanical precision is required in terms of concentricity between the laminated stator core and the rotor, and concentricity between the output shaft of the rotor and the motor attachment part of a machine tool, etc. 1st
2 and 2, conventionally, thick end plates 3 and 4 are disposed at both ends of a laminated stator core 1 having laminated thin steel plates 2.
and the end plates 3 and 4 are firmly welded and fixed via a plurality of reinforcing rods (not shown), and the stator winding 6 is attached to the assembly 5 of the laminated stator core 1 and the end plates 3 and 4.
After winding the brackets, fitting portions 3a for fitting the brackets 7, 8 to the end plates 3, 4 of this assembly 5,
4a is formed by precision machining, while the brackets 7 and 8 have bearing member mounting surfaces 7a and 8a.
The fitting surfaces 7b and 8b to the fitting parts 3a and 4a are precisely machined in advance, and then the pair of brackets 7 and 8 are fitted into both ends of the assembly 5, and the pair of brackets are tightened with the fastening bolts 9. 7, 8 and the assembly 5 are firmly fixed, and a rotor (not shown) is rotatably supported by the stator brackets 7, 8 formed in this way via bearing members (not shown), thereby achieving a laminated type fixation. A motor was completed in which the child core 1 formed part of the outer jacket.

However, in the electric motor formed by the method described above, since the pre-machined assembly 5 and the pair of brackets 7 and 8 are connected, mechanical precision errors of each joint are accumulated due to the connection, and The tightening force of the bolts 9 causes distortion in the brackets 7, 8, etc., resulting in a decrease in the dimensional accuracy of the completed assembly. Further, since it is necessary to precisely machine the end plates 3, 4 of the assembly 5 and the fitting portions of the pair of brackets 7, 8, the number of man-hours for precision machining increases. Furthermore, since it is necessary to provide end plates at both ends of the laminated stator core 1, the number of parts and processing steps increase, leading to an increase in costs.

Purpose of the Invention In view of the problems of the prior art described above, the present invention provides an electric motor with high mechanical dimensional accuracy in a type of electric motor that uses a laminated stator core as a part of the motor jacket, and also provides such a high It is an object of the present invention to provide a method for manufacturing a high-precision electric motor at low cost and with a small number of processing steps.

Structure of the Invention According to the present invention, a laminated stator core made of a large number of laminated and bonded steel plates, a stator winding provided on the laminated stator core, and a stator winding provided on the laminated stator core; A pair of brackets bonded to both ends of the laminated stator core with an adhesive, and a fastening rod means that extends through the laminated stator core and firmly connects the pair of brackets and the laminated stator core. and a rotor rotatably supported by the pair of brackets via bearing members,
The parts of the bracket that are important for mechanical precision, such as the mounting surface for the bearing member and the mounting surface for external equipment, are formed by machining while the laminated stator core and the bracket are bonded and fastened. This is achieved by an electric motor characterized by:

Further, according to the present invention, the above object is achieved by providing a stator winding on a laminated stator core made of a large number of laminated and mutually fixed steel plates, and then installing bearings at both ends of the laminated stator core. a pair of brackets for rotatably supporting the rotor via a member are adhered with an adhesive, and then the pair of brackets and the laminated stator core are connected to each other by a fastening rod that penetrates the laminated stator core. After that, parts of the bracket that require mechanical precision, such as the mounting surface for the bearing member and the mounting surface for external equipment, are formed by machining, and then the pair of rotors are connected via the bearing member. This is achieved by a method of manufacturing an electric motor, characterized in that the electric motor is rotatably attached to the bracket of the electric motor.

Embodiments of the Invention Hereinafter, embodiments of the device of the present invention will be described along with a manufacturing method thereof.

3 and 4 show an embodiment in which the present invention is applied to a permanent magnet field type synchronous motor,
Figures 5 to 7 show the manufacturing process. Referring to these figures, the permanent magnet field type synchronous motor includes a laminated stator core 21 made of a large number of laminated electromagnetic steel plates 22. The laminated stator core 21 becomes part of the outer jacket of the motor. As shown in FIG. 5, the electromagnetic steel plate 22 is usually formed into a predetermined shape by punching an electromagnetic steel plate material. Here, the electromagnetic steel plate 22 is made to have a substantially octagonal outer shape, but the outer shape may be circular, for example. Here, the electromagnetic steel plates 22 of the laminated stator core 21 are fixed to each other and integrated along the lamination direction by welded portions indicated by the reference numeral 23 in FIGS. 3 and 6. For example, TIG welding can be used for welding. Note that instead of welding, the laminated stator core 21 may be integrated using adhesive, caulking, clipping means, or the like.

Laminated stator core 2 integrated as described above
1 is wound with a stator winding 24 in a conventional manner. A portion of the stator winding 24 protrudes from both end faces of the laminated stator core 21, and the protruding portion is molded with resin.

Brackets 29,
30 are adhered with adhesives 27 and 28, respectively. The pair of brackets 29 and 30 and the laminated stator core 21 are connected to the laminated stator core 21.
A plurality of fastening rod means passing through the
Here, it is firmly fastened and fixed by a fastening bolt 31. The fastening bolt 31 is attached to one of the brackets 2
It is screwed into a screw hole 32 formed in 9. The pair of flanges 29 and 30 and the laminated stator core 21 may be fastened together using fastening bolts and nuts.

A bearing member 33 consisting of a holder 34 and a bearing 35 is attached to one bracket 29, and a bearing member 36 consisting of a holder 37 and a bearing 38 is attached to the other bracket 30. The bearing members 33 and 36 are attached to the brackets 29 and 36 by means such as screwing or press fitting.
Attached to 30. These bearing members 33, 36
A shaft 40 of a rotor 39 is fitted into the bearings 35 and 38 by means such as press fitting. Here, the rotor 39 is mounted on a shaft 40 with a permanent magnet 41 and a yoke 4 made of a large number of laminated electromagnetic steel plates.
However, when the present invention is applied to an induction motor, a rotor having windings is used.

Bearing members 3 are attached to the brackets 29 and 30, respectively.
Mounting portions 29a and 30a are formed for positioning and holding the holders 34 and 37 of 3 and 36, and a mounting portion 29b is formed on the output side bracket 29 for positioning and holding the holders 34 and 37 on a machine tool, etc. There is. These mounting portions have a cylindrical surface and an end surface perpendicular to the central axis of the cylindrical surface. These mounting portions are precisely machined with a pair of brackets 29, 30 and a laminated stator core 21 firmly fastened and fixed using adhesives 27, 28 and fastening bolts 31. This machining can be performed by fitting the inner peripheral surface of the laminated stator core 21 into a mandrel of a cutting machine. Fastening bolt 3
Even if the laminated stator core 21 and the brackets 29, 30 are slightly deformed due to the tightening force in step 1, the mounting portions of the brackets 29, 30 are machined afterwards, so the desired shape can be achieved. It can be finished with precision. The brackets 29 and 30 are fastened and fixed by fastening bolts 31 while being bonded to both end faces of the laminated stator core 21, which is made up of a number of laminated steel plates 22 that are fixed to each other, so that they can be fastened and fixed by fastening bolts 31 during machining or after machining. This makes it possible to reliably prevent misalignment between the laminated stator core 21 and the brackets 29, 30.

Therefore, the laminated stator core 21 and rotor 3
9, the concentricity between the shaft 40 of the rotor 39 and the motor mounting part of the machine tool, etc., and
Accuracy errors such as the perpendicularity between the motor mounting part of a machine tool etc. and the shaft 40 of the rotor 39 are determined only by the accuracy during machining, and the laminated stator core 21, brackets 27, 30, etc. Accumulation of errors due to the combination of is impossible.

Since the rotor 39 is inserted into the laminated stator core 21 and the pair of brackets 29 and 30 after they are fastened and fixed, the inner diameter of one of the brackets, here the bracket 30, is larger than the maximum outer diameter of the rotor 39. is also set large. The inner diameter of the other bracket 29 may be smaller than the outer diameter of the rotor 39. Note that the bearing members 33 and 36 are attached to the bracket 2.
It may also consist only of bearings that are press-fitted into the bearings 9 and 30.

The electric motor with the above configuration is first laminated and welded.
After the stator windings 24 are provided on a laminated stator core 21 made up of a large number of steel plates 22 fixed to each other by means 3, a rotor is attached to both ends of the laminated stator core 21 via bearing members 33 and 36. A pair of brackets 29, 30 for rotatably supporting the bracket 39 are adhered with adhesive, and then the pair of brackets 29, 30 are attached with an adhesive.
30 and the laminated stator core 21 are firmly fastened with fastening bolts 31 passing through the laminated stator core 21, and then the mounting surfaces 29a, 30a for bearing members in the brackets 29, 30 and external equipment such as machine tools are connected. The mounting surface 29b is formed by machining, and then the rotor 39 is rotatably mounted to the pair of brackets 29, 30 via the bearing members 33, 36, thereby completing the assembly.

As mentioned above, after the laminated stator core 21 and the brackets 29, 30 are firmly fastened and fixed, the parts that require mechanical precision are precisely machined. It is no longer necessary to process the joints with high precision in advance. If the brackets 29 and 30 are, for example, aluminum die-cast products, they can be combined with the laminated stator core 21 without any machining after molding, and then can be machined, which greatly reduces the number of machining steps. . Also, bracket 29,
Laminated stator core 21 with coupling recess for 30
Laminated stator core 2
It is not necessary to provide thick end plates at both ends of the device. Therefore, the number of parts can be reduced.

One embodiment and several modifications have been described above, but according to the electric motor and method for manufacturing the same according to the present invention, various changes can be made within the scope of the invention as set forth in the claims.

Effects of the Invention As is clear from the above description, the electric motor according to the present invention includes a laminated stator core made of a large number of laminated and bonded steel plates, and a stator winding provided on the laminated stator core. A wire, a pair of brackets bonded to both ends of the laminated stator core with an adhesive, and a wire extending through the laminated stator core to firmly connect the pair of brackets and the laminated stator core. It includes a fastening rod means for fastening, and a rotor that is rotatably supported by the pair of brackets via bearing members, and the mounting surface for the bearing members in the brackets, the mounting surface for external equipment, etc. Since the necessary parts are formed by machining with the laminated stator core and the bracket bonded and fastened together, the number of parts is small and the mechanical precision is high. This means that we can provide electric motors.

In particular, the bracket in the present invention is fastened and fixed by fastening bolts while being bonded to both end faces of the laminated stator core, which is made up of a large number of laminated steel plates that are fixed to each other. Misalignment between the laminated stator core and the bracket can be reliably prevented.

Further, in the method for manufacturing an electric motor according to the present invention, after providing stator windings on a laminated stator core made of a large number of laminated and mutually fixed steel plates, bearing members are attached to both ends of the laminated stator core. A pair of brackets for rotatably supporting the rotor are bonded together with an adhesive, and then the pair of brackets and the laminated stator core are connected by fastening rod means passing through the laminated stator core. After fastening firmly, parts of the bracket that require mechanical precision, such as the mounting surface for the bearing member and the mounting surface for external equipment, are formed by machining, and then,
Since the rotor is rotatably attached to the pair of brackets via bearing members, the combination of the laminated stator core and the brackets must be performed before the laminated stator core and the brackets are connected. There is no need to machine the surface with high precision or to insert end plates or the like. Therefore, an electric motor with a small number of parts and high mechanical precision can be manufactured at low cost and with a small number of manufacturing steps.

[Brief explanation of drawings]

Fig. 1 is a schematic exploded sectional view of a stator of a conventional electric motor, Fig. 2 is a partial sectional view showing an assembled state of the stator of the electric motor shown in Fig. 1, and Fig. 3 is an embodiment of the device of the present invention. 4 is a partial right side view of the electric motor shown in FIG. 3, and FIG. 5 is a sectional view of the electric motor shown in FIG.
FIG. 6 is a perspective view showing the laminated stator core of the motor shown in FIG. 3 during manufacture, and FIG. 7 is a perspective view of the stator assembly of the motor shown in FIG. 3. It is an exploded schematic sectional view showing a state in the middle of attachment. 21... Laminated stator core, 22... Steel plate, 23...
Welded portion, 24... Stator winding, 27, 28... Adhesive, 29, 30... Bracket, 31... Fastening bolt, 33, 36... Bearing member, 39... Rotor.

Claims (1)

[Scope of Claims] 1. A laminated stator core made of a large number of laminated and bonded steel plates, a stator winding provided on the laminated stator core, and both ends of the laminated stator core. a pair of brackets bonded to each other with an adhesive; a fastening rod means extending through the laminated stator core and firmly fastening the pair of brackets and the laminated stator core; and a rotor rotatably supported via a bearing member, and parts of the bracket that require mechanical precision, such as the mounting surface for the bearing member and the mounting surface for external equipment, are connected to the laminated stator core. An electric motor characterized in that the electric motor is formed by machining in a state where the bracket is bonded and fastened. 2. After installing stator windings on a laminated stator core consisting of a large number of laminated and bonded steel plates,
A pair of brackets for rotatably supporting the rotor are bonded to both ends of the laminated stator core with an adhesive via bearing members, and then the pair of brackets and the laminated stator core are attached to the laminated stator core. It is firmly fastened by a fastening rod means that penetrates the laminated stator core, and then, parts of the bracket that require mechanical precision, such as the mounting surface for the bearing member and the mounting surface for external equipment, are formed by machining, A method of manufacturing an electric motor, comprising: thereafter rotatably attaching a rotor to the pair of brackets via a bearing member.