JPH08149740A - Stator assembly for motor - Google Patents

Abstract

PURPOSE: To obtain a stator assembly for a motor in which the process for assembling various kinds of stator assemblies, having different functions on the side of a front supporting member, can be shared at least partially. CONSTITUTION: The stator assembly comprises a stator core 14, and front and rear supporting members 16, 18 disposed, respectively, at the front and rear ends of the stator core 14 in order to hold and secure the stator core 14. The front supporting member 16 comprises an auxiliary element 22 being secured to the stator core 14 and a main element 24 being fixed to the front end of the auxiliary element 22. A front bearing 32 for supporting a shaft 28 is fitted in the central hole 30 of the main element 24 whereas a rear bearing 44 for supporting the shaft 28 is fitted in the central hole 42 of the rear supporting member 18. The main element 24 is secured to the auxiliary element 22 after a semi-assembly, comprising the stator core 14, the rear supporting member 18 and the auxiliary element 22, is subjected to finish work. The main element, serving as a brake housing, can be coupled with the auxiliary element 22 in place of the main element 24.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stator assembly for an electric motor, and more particularly, to a stator core surrounding a rotor with a gap, and a stator core which is arranged at each of a front end and a rear end of the stator core in an axial direction to fixedly sandwich the stator core. In addition, the present invention relates to a stator assembly of an electric motor that includes a front support member and a rear support member that rotatably support the rotor via front and rear bearings, respectively.

[0002]

2. Description of the Related Art Heretofore, there has been known an electric motor of a type in which a stator is arranged outside a rotor, in which a housing for accommodating and supporting a stator core is omitted in order to reduce an outer diameter size. In this type of electric motor, generally, a stator core is fixedly sandwiched by a pair of support members respectively arranged at both ends in the axial direction, whereby a stator assembly is formed.

When the output end side of the shaft of the electric motor is front, the front support member of the pair of support members is integral with the peripheral wall portion fixed to the axial front end surface of the stator core and the front end of the peripheral wall portion. End wall portion extending inward in the radial direction. A hole through which the shaft of the rotor passes is defined in the center of the end wall portion, and a front bearing that rotatably supports the shaft is installed in this hole. Further, a flange for mounting the electric motor on the driven machine is formed on the outer edge of the end wall portion of the front support member.

The rear support member includes a first element that forms a cylindrical wall portion that is fixed in contact with the axial rear end surface of the stator core,
A second element attached to the rear end of the first element to form a radially extending end wall. The first element has a central opening into which the rotor can be inserted, and a hole through which the shaft of the rotor passes is defined in the center of the second element, and a rear bearing for rotatably supporting the shaft is installed in the hole. .

When assembling a rotor into a conventional stator assembly of this type, first, the front support member and the first element of the rear support member are fixed to the stator core, and then the rotor is inserted into their internal spaces. The second element is connected to the first element while the shaft is supported by the front bearing installed on the front support member and finally the shaft is supported by the rear bearing installed on the second element of the rear support member.

By the way, the stator core is generally formed by laminating a plurality of magnetic thin plates such as silicon steel plates and connecting them to each other by, for example, welding or caulking. Therefore, due to the slight warpage and bending of the magnetic thin plates that occur during mutual coupling,
The laminated stator core may have a slight deflection with respect to the axis. When such a bent stator core is fixed to the front support member and the rear support member that have been subjected to finish processing in advance in the bearing installation portion, the axes of the front bearing and the rear bearing are not arranged on the same straight line, There is a risk that the shaft cannot be supported. Therefore, conventionally, in the state where the front support member and the first element of the rear support member, which have not been finished yet, are fixed to the stator core and are integrally supported by a jig, the bearing mounting surface of the front support member, Mounting surface (inlay portion) of the front support member to the driven machine, first
After cutting and finishing the second element mounting surface of the element and the like, the second element having the bearing mounting surface and the mounting surface for the first element finished in a separate step is connected to the first element.

[0007]

When the electric motor having the stator assembly as described above is applied to a servomotor, a brake unit for holding the shaft stationary may be mounted on the shaft. In this case, generally, the rotating portion of the brake unit is fixed to the front end side of the shaft, and the stationary portion is housed in the brake housing. The brake housing is arranged on the axial front end surface of the stator core instead of the front support member described above. A front bearing is installed in the brake housing similarly to the front support member, and a flange for mounting on the driven machine is formed. Here, as described above, in order to eliminate the axial displacement of the bearing due to the bending of the stator core, a cylindrical auxiliary element that is abutted and fixed to the axial front end surface of the stator core is arranged between the brake housing and the stator core. It

With such a construction, in order to obtain the alignment of the bearing with respect to the shaft and the alignment of the shaft with respect to the machine to be driven,
After the auxiliary element and the first element of the rear support member, which have not been finished, are fixed to the stator core and are integrally supported by a jig, the auxiliary element and the first element are subjected to cutting and finishing, and then the auxiliary element. The second housing is connected to the first housing, and the second housing is connected to the brake housing whose bearing mounting surface and the like are finished in a separate process.

As described above, the electric motor with the brake unit and the electric motor without the brake unit have different constructions of the stator subassemblies at the stage of performing the cutting finishing process, so that the operation setting of the cutting machine corresponding to each is required. Therefore, the processing work was complicated. Further, in particular, since the stator assembly of the electric motor including the brake unit has a large number of parts as described above, there is a problem that the cost increases and the assembling work becomes complicated.

An object of the present invention relates to an electric motor having a plurality of types of stator assemblies having different functions on the front support member side, such as an electric motor having a brake unit on the output end side of a shaft and an electric motor not having a brake unit. An object of the present invention is to provide a stator assembly of an electric motor that can reduce the manufacturing cost of each electric motor by at least partially standardizing the assembly process of the assembly. Another object of the present invention is to provide a stator assembly of an electric motor that can reduce the number of parts of the stator assembly of the electric motor with a brake unit and simplify the assembly work.

[0011]

In order to achieve the above object, the present invention provides a stator core that surrounds a rotor with a gap, and a stator core that is disposed in contact with the axial front end surface and rear end surface of the stator core, respectively. In a stator assembly of an electric motor, which includes a front support member and a rear support member that are fixedly sandwiched and that rotatably support a rotor via a front bearing and a rear bearing, the rear support member is a rear bearing. Has a wall extending in the radial direction, and the front support member has an auxiliary element fixed to the axial front end surface of the stator core with an opening into which the rotor can be inserted, and the front bearing as a center. A main element having a wall extending in the radial direction to be installed and fixedly connected to the auxiliary element, and a desired main element is selected from a plurality of main elements having different functions, and the auxiliary element is optionally selected. Providing stator assembly body of the motor, characterized in that it can be connected.

[0012]

With the auxiliary element of the front supporting member and the rear supporting member fixed to the stator core, the main element mounting surface of the auxiliary element, the bearing mounting surface of the rear supporting member, etc. are subjected to cutting and finishing. As for the main element of the front support member, the mounting surface to the driven machine, the bearing mounting surface, etc. are finished in a separate process. The rear bearing is then installed on the rear support member and the front bearing is installed on the main element of the front support member. Next, in the internal space formed by the stator core, the auxiliary element, and the rear support member,
The rotor is inserted through the opening of the auxiliary element so that the rear bearing of the rear support member supports the rotor shaft. Finally, the main element is connected to the auxiliary element while the shaft is supported by the front bearing of the main element of the front support member.

At this time, for example, one of the main element that acts only as the mounting flange and the main element that also acts as the brake housing can be selected and connected to the auxiliary element as desired. Therefore, since the stator subassemblies at the stage of performing the cutting finish have the same structure in the motor with the brake unit and the motor without the brake unit, the assembly process of both motors is partially standardized and their manufacturing costs are reduced. Is reduced. Further, the number of parts of the stator assembly of the electric motor including the brake unit is reduced as compared with the conventional one, so that the assembling work is simplified.

[0014]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing a preferred embodiment of the present invention. In each drawing,
The same components are designated by common reference numerals. FIG. 1 shows a stator assembly 10 of an electric motor according to an embodiment of the present invention.
The stator assembly 10 includes a stator core 14 that surrounds the rotor 12 with a gap, and a front support member 16 and a rear support member that are respectively arranged at the front end and the rear end of the stator core 14 in the axial direction to fixedly sandwich the stator core 14. 18 and. The stator core 14 is formed by laminating a plurality of magnetic thin plates such as silicon steel plates and connecting them to each other by, for example, welding or caulking. The windings 20 are installed in a plurality of slots 19 (see FIG. 2) formed in the inner peripheral portion of the stator core 14 at equal intervals in the circumferential direction.

The front support member 16 has an auxiliary element 22 that forms a cylindrical wall portion that is fixed in contact with the axial front end surface of the stator core 14, and an end that is attached to the front end of the auxiliary element 22 and extends in the radial direction. It comprises a main element 24 forming a wall. The auxiliary element 22 comprises a central opening 26 into which the rotor 12 can be inserted. A hole 30 through which the shaft 28 of the rotor 12 passes is defined in the center of the main element 24, and a front bearing 32 that rotatably supports the shaft 28 is installed in the hole 30. Further, on the outer edge of the main element 24, a flange 3 for mounting the electric motor on a target machine is driven.
4 is projected radially outward. The mounting flange 34 has a bolt hole 36 through which a mounting bolt (not shown) penetrates.
(See FIG. 4) is formed.

The rear support member 18 includes a peripheral wall portion 38 which is fixedly contacted with an axial rear end surface of the stator core 14, and a peripheral wall portion 3.
8 and an end wall portion 40 integrally extending radially inward from the rear end. A hole 42 through which the shaft 28 of the rotor 12 passes is defined in the center of the end wall portion 40, and a rear bearing 44 that rotatably supports the shaft 28 is installed in the hole 42. Winding 20
The auxiliary element 22 of the front support member 16 and the rear support member 18 are attached to the stator core 14 on which the plurality of bolts 46 are installed.
(See FIG. 2). The bolt 46 is inserted, for example, from the rear support member 18, penetrates the stator core 14, and is screwed to a female screw portion 48 (see FIG. 3) provided on the auxiliary element 22. In the state of this subassembly, a resin impregnation step is performed for the purpose of insulating and waterproofing the laminated structure of the stator core 14 and fixing the winding 20.

Further, this subassembly is a jig (not shown).
The main element mounting surface 50 of the auxiliary element 22, the bearing mounting surface 52 of the rear support member 18, and the like are subjected to cutting finishing. The main element 24 of the front support member 16 has a mounting surface 54, a bearing mounting surface 56, etc. for the driven machine machined in a separate process. Then, the rear bearing 44 is installed on the bearing mounting surface 52 of the hole 42 of the rear support member 18, and the front bearing 32 is installed on the bearing mounting surface 56 of the hole 30 of the main element 24 of the front support member 16. Next, the rotor 12 is inserted through the central opening 26 of the auxiliary element 22 into the internal space formed by the stator core 14, the auxiliary element 22, and the rear support member 18, and the shaft 28 is attached to the rear bearing 44 of the rear support member 18. Support.
Finally, the front bearing 32 of the main element 24 of the front support member 16
The main element 24 is connected to the auxiliary element 22 while supporting the shaft 28 in the. As shown in FIG. 4, the main element 24 is fixed to the auxiliary element 22 by a plurality of bolts 58. These bolts 58 are provided at a position different from that of the female screw portion 48 and the auxiliary element 2 is provided.
It is screwed to the female screw portion 60 (see FIG. 3) provided on the No. 2.

Instead of the main element 24, the stator assembly 10 can have a main element 62 acting as a brake housing as shown in FIG. Main element 62
Is the peripheral wall portion 6 fixed to the axial front end surface of the auxiliary element 22.
4 and an end wall portion 66 integrally extending radially inward from the front end of the peripheral wall portion 64. A hole 68 through which the shaft 28 of the rotor 12 passes is defined in the center of the end wall portion 66.
A front bearing 70 that rotatably supports the shaft 28 is installed on the shaft 8. On the outer edge of the main element 62, a flange 72 for attachment to the machine to be driven by the electric motor is formed. Further main element 62
Is the stationary part of the brake unit (only the coil 74 is shown)
Is housed and fixedly supported. The rotating portion (not shown) of the brake unit is fixedly connected to the front end side of the shaft 28 corresponding to the stationary portion.

As described above, the main element 62 is the stator core 1
The subassembly consisting of 4, the rear support member 18, and the auxiliary element 22 can be fixed to the auxiliary element 22 by means of a plurality of bolts (not shown) like the main element 24 after finishing as described above. . Further, the main element 62 has a mounting surface 76 and a bearing mounting surface 78, etc., to be machined as a drive target, which are finished in a separate process. Therefore, the assembling process of the electric motor having the brake unit and the electric motor not having the brake unit is made common until the stage where the stator subassembly is subjected to the cutting and finishing process, so that the manufacturing cost of both electric motors is reduced. Further, since the rear support member 18 is an integral member, the number of parts of the stator assembly of the electric motor including the brake unit is reduced as compared with the conventional one, and the assembling work thereof is simplified.

Although the present invention has been described based on the preferred embodiments, the present invention is applicable to various types of stator sets having mounting flanges of different shapes corresponding to the shape of the mounting portion of the machine to be driven. It also works extremely effectively when producing the body. In this case, by dividing the front support member into a main element having a mounting flange and an auxiliary element fixed to the stator core, all types of stator assemblies are assembled up to the stage of finishing the subassembly. The process is standardized, and thus the manufacturing cost is reduced.

[0021]

As is apparent from the above description, according to the present invention, the rear support member of the stator assembly is an integral member, and the front support member is fixed to the auxiliary element fixed to the stator core and the auxiliary element. Formed from the main element connected to
A desired main element is selected from a plurality of main elements having different functions and can be connected to the auxiliary element at any time. Therefore, according to the present invention, there is provided a motor having a plurality of types of stator assemblies having different functions on the front support member side, such as a motor having a brake unit on the output end side of a shaft and a motor not having the brake unit. The assembly process of is standardized at least up to the stage before connecting the main element to the auxiliary element,
This reduces the manufacturing cost of each electric motor. Also,
Since the number of parts of the stator assembly of the electric motor with a brake unit is reduced as compared with the conventional one, the assembling work is simplified.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional exploded side view of a stator assembly of an electric motor according to an embodiment of the present invention, which is shown with a rotor.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is a sectional view taken along line III-III in FIG.

FIG. 4 is a cross-sectional view taken along line IV-IV in FIG.

5 is a partial cross-sectional exploded side view of a stator assembly of an electric motor according to another embodiment of the present invention having a front support member different from the stator assembly of FIG.

[Explanation of symbols]

 12 ... Rotor 14 ... Stator core 16 ... Front support member 18 ... Rear support member 20 ... Winding 22 ... Auxiliary element 24, 62 ... Main element 26 ... Center opening 28 ... Shaft 30, 42, 68 ... Hole 32, 70 ... Front Part bearings 34, 72 ... Mounting flanges 44 ... Rear part bearings 46, 58 ... Bolts 48, 60 ... Female thread part 74 ... Coil

Claims (1)

[Claims] 1. A stator core that surrounds a rotor with a gap, and axially front and rear ends of the stator core are respectively disposed to fixedly sandwich the stator core and through a front bearing and a rear bearing, respectively. In a stator assembly of an electric motor comprising a front support member and a rear support member that rotatably support the rotor, the rear support member has a wall extending in a radial direction centered on the rear bearing. An auxiliary element fixed to the axial rear end surface of the stator core; the front support member having an opening into which the rotor can be inserted and fixed to the axial front end surface of the stator core; A main element fixedly connected to the auxiliary element with a wall extending in the radial direction centering on the partial bearing, and a desired main element from a plurality of main elements having different functions Can be connected to the auxiliary element at any time by selecting.