JPH0520989B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method of manufacturing a stator for brushless motors such as step motors, induction motors, and hysteresis motors.

(Prior Art) Brushless motors are widely used as small control motors such as step motors. FIG. 2 is a plan view showing the configuration of a conventional brushless motor as viewed from the axial direction. A stator 4 is disposed around the outer periphery of a rotor 3, which is composed of a rotating shaft 1 and a permanent magnet 2 fixed to the outer periphery of the rotor 3. The stator 4 is composed of a core 5 made of laminated stamped silicon steel plates and three coils 6a to 6c.The core 5 has three magnetic pole parts 7a to 7c that protrude to face the rotor 3. It has a yoke part 8 that forms a magnetic path, and each coil 6a to 6c is wound around each magnetic pole part so as to supply magnetic flux in the direction of the rotor 3.

When an excitation current is sequentially applied to each coil 6a to 6c,
A rotating magnetic field directed toward the rotor 3 is sequentially formed between each magnetic pole via the yoke 8, and the rotor 3 rotates.

Various types of brushless motors have been put into practical use, from large motors to small motors.
Because it has a simple configuration and is easy to maintain, it is used as a small motor for control purposes.In particular, with the development of small control equipment, there is a demand for the development of small brushless motors with large torque.

(Problems to be Solved by the Invention) The stator of a brushless motor is assembled by bundling stamped silicon steel plates to assemble a core, and then installing coils in slots formed between each magnetic pole of the core. However, the slot where the coil is installed and the space around it are restricted by the surrounding yoke and magnetic poles and are extremely narrow, so installing the coil requires a lot of effort and skilled technique, making it difficult to assemble the motor. There were many difficulties.

In particular, if the motor becomes smaller, it becomes impossible to use an automatic coil winding machine. As a result, the number of motor poles and
Another problem has arisen in that the lengths of the core in the radial and axial directions are limited. Therefore, with simple work,
There is a strong demand for the development of a stator for brushless motors that allows coils to be easily attached and that allows the motor to have multiple poles and improve volumetric efficiency.

(Means for Solving the Problems) In the stator manufacturing method according to the present invention, when manufacturing a stator for a brushless motor, a large number of magnetic pole plates are laminated to form a plurality of magnetic pole portions consisting of magnetic pole plate rows. A core body is assembled by arranging a plurality of magnetic pole parts at equal intervals around the central axis of the rotor between a pair of fixed members made of non-magnetic material, and integrally directing them. Insert a circular positioning jig and press each magnetic pole part from its outer periphery toward the shaft center to bring the inner circumferential surface of the core body into contact with the outer circumferential surface of the positioning jig and separate the magnetic pole plates. After aligning and positioning the core body and attaching a coil to each of the magnetic pole parts, the yoke part is formed by wrapping a sheet made of a magnetic material around the outer periphery of the core body.

(Function) In the present invention, the magnetic pole part and the yoke part constituting the core are constructed separately, and the silicon steel plates punched and formed to form the magnetic poles are bundled to assemble the magnetic pole parts in the number corresponding to the number of magnetic poles, and these are assembled into a bracket. and a positioning jig to accurately position and fix the rotor to be mounted with reference to its central axis. Next, a coil is attached to each magnetic pole part without the yoke part, and after the coil is attached, the outer end of the magnetic pole part is wrapped with a thin silicon steel plate so that a magnetic path is formed between each magnetic pole part to form a yoke part. do. As a result, a wide space unrestricted by the yoke can be secured around each magnetic pole part when the coil is mounted, the coil can be easily mounted with simple work, and an automatic coil winding machine can be used.

(Example) In the present invention, the magnetic pole part and the yoke part that constitute the core of the stator are constructed separately, the magnetic pole parts that supply magnetic flux to the rotor are assembled to form a core body, and a coil is attached to each magnetic pole part. , After the coil is attached, the yoke section is attached to the outer periphery of the magnetic pole section. FIG. 1 is a perspective view showing the structure of an example of a core body of a stator according to the present invention, and FIG. 3 is a perspective view showing a state in which a bracket is removed from the core body. The core body 10 is 3
The three magnetic pole parts 11 are each configured independently, and two brackets 12 are used to arrange the magnetic pole parts 11 so that the surfaces facing the rotor face each other at 120 mm. They are connected radially, spaced apart by an angle of °. The magnetic pole part 11 has two types of magnetic pole plates 13 and 14 made of silicon steel plates, and a first magnetic pole plate 13 and a first magnetic pole plate 14 on both ends.
A second magnetic pole plate 14 is placed in the center and laminated in the same direction, and the through holes formed in each magnetic pole plate 13 and 14 are made of a high magnetic permeability material. They are integrally bundled through a shaft 15. Further, in this state, insulation treatment is applied to the necessary parts, and then the inner surfaces 13a and 1
It is preferable to align them on the same circumference by re-grinding 4b.

FIGS. 4A and 4B are plan views showing the shape of the magnetic pole plate constituting the magnetic pole part, and FIG.
The figure B shows the shape of the first magnetic pole plate 13 disposed on both end sides in contact with, and the figure B shows the shape of the second magnetic pole plate 14 disposed in the center. The second magnetic pole plate 14 will be explained. When installed, the inner end 14a facing the rotor and the outer end 14b contacting the yoke part are formed into an arc shape, and protrusions 14c and 14d are integrally provided, respectively.
A slot for installing the coil is formed between the two. In addition, the shaft 1 is located slightly outside the center.
A through hole 14e into which the screw 5 is to be inserted is formed. Note that the first magnetic pole plate 13 has a protrusion removed from its inner end for ease of attachment, but the other configurations are the same in shape as the second magnetic pole plate 14, so a description thereof will be omitted.

Figure 5 shows the configuration of an example of the bracket, with Figure A being a front view and Figure B being a - of Figure 5A.
A line sectional view, and C of the same figure is a back view. The bracket 12 is made of a heat-resistant non-magnetic material such as resin or ceramic material, and has three radially projecting legs 12a to 12c formed at intervals of 120°, and a space between the legs 12a to 12c. are three protrusions 12d to 1
2f is formed. A flange portion 1 is provided on the surface opposite to the surface on which the protrusions 12a to 12f are formed.
Forms 2g. Each leg 12a to 12f supports a magnetic pole part 11 made up of laminated magnetic pole plates 13 and 14, and its outer diameter is equal to that of the magnetic pole plates 13 and 14.
The holes 12h to 1 are formed at positions slightly larger than the outer diameter of the center part, and are located slightly outward from the center.
2j, and a sleeve made of a magnetic material is press-fitted into each hole 12h to 12j. The inner diameter of this sleeve is such that the shaft 15, which bundles the magnetic pole plates 13 and 14, can be loosely fitted therein. In addition, each protrusion 1
The interval between 2d and 12f is for fitting and supporting the first magnetic pole plate 13, and thereby each magnetic pole plate 13
and 14 are aligned and supported in the axial direction of the motor body.

Next, a method for manufacturing a stator according to the present invention will be explained. First, a predetermined number of first and second magnetic pole plates 13 and 14 are stacked and aligned and supported by a shaft 15 to form three magnetic pole plate rows, and brackets 12 are attached to both ends of these magnetic pole plate rows. The core body 10 is integrally supported by the shaft 15 and assembled.

Next, position the magnetic pole part and attach the coil.

The positioning of the magnetic pole part 11 and the magnetic pole plate is performed using a positioning jig 16 at the center of the core body into which the rotor is inserted.
This is done by inserting. FIG. 6 is a plan view showing the structure of an example of a positioning jig according to the present invention. The positioning jig 16 is made of a metal material with a small coefficient of friction, and has a cylindrical positioning part 16a and a shaft part 16b at both ends thereof, and a threaded part is formed in the shaft part 16b. The outer diameter of the positioning part 16a is the same as the outer diameter of the rotor used, and the magnetic pole part 1 facing the rotor
Set the length to be the distance from the inner edge of 1. The inner diameter of the flange 12g of the bracket 12 is made to substantially match the outer diameter of the positioning portion 16a.
FIG. 7 is a cross-sectional view taken along a plane passing through the center of the magnetic pole portion, showing the positioning state of the core body. The positioning jig 16 is inserted into the core body 10, and the magnetic pole plate 13 is pushed from the outer periphery of each magnetic pole part 10 by the pressing member 17.
and 14 toward the center of the shaft. Each magnetic pole plate 1
Since the inner ends of the magnetic pole plates 13 and 14 are formed with arcs equal to the outer diameter of the positioning jig 16,
and the inner end of the positioning jig 16 is engaged with the outer peripheral surface of the positioning jig 16, so that each magnetic pole plate is aligned and positioned with respect to the motor body, and each magnetic pole portion 11 is also positioned with respect to the central axis of the motor body. become. Also, a washer 18 is attached to the shaft portion 16b of the positioning jig 16.
The nuts 19 are screwed together through the screws, the bracket 12 is pressed from both ends in the axial direction, and both ends of the shaft 15 are caulked to the bracket 16 to fix the magnetic pole plates 13 and 14. After positioning and fixing the magnetic pole parts, the core body 10 is insulated, and then the coils are installed in slots formed around each magnetic pole part 10. The coil is attached by attaching an already wound coil or by winding an insulated conductor wire. Next, the core body to which the coil is attached is treated with varnish to fix the core body and each core. Note that this varnish treatment may be performed after the yoke portion is attached.

Next, the yoke portion is attached to the core body. FIG. 8 is a sectional view taken perpendicular to the central axis of the stator to which the yoke portion 20 is attached. After the coil 21 is attached to the magnetic pole part 11, a thin magnetic sheet such as a thin silicon steel plate having a thickness of 0.2 to 0.5 mm or less is wound around the outer periphery of the core body 10 so as to be in close contact with each magnetic pole part 11, and then heat-shrinked. The yoke portion 20 is formed by fixing with a tube, heat-resistant adhesive tape, heat-resistant adhesive, or the like. In this case, the magnetic sheet constituting the yoke portion 20 is preferably a magnetic material with an iron loss of 7.75w/Kg or less. The outer ends of the magnetic pole plates 13 and 14 constituting the magnetic pole part have a circular shape, and the thin magnetic sheet has flexibility, so that the yoke part 20 and the magnetic pole part 11
A large contact area is formed between the two and a good contact condition can be ensured. As a result, the magnetic resistance between the yoke portion 20 and each magnetic pole portion 11 can be made extremely small, and the magnetic circuit constituted by the yoke portion 20 and the magnetic pole portions 11 operates well. Next, the positioning jig 16 is removed and the casing is attached to complete the process.

FIG. 9 is a sectional view showing the structure of an example of a brushless motor using a stator according to the present invention. A permanent magnet 31 is fixed to a rotating shaft 30 to constitute a rotor. The stator 32 is mounted around the rotor with a predetermined gap. The magnetic pole part 3 of this stator 32
3 has a structure in which magnetic pole plates 34 are laminated and frozen, and brackets 35 are attached to both ends of the magnetic pole plates 34 to align and fix them.
A coil 36 is installed in the slot around the magnetic pole part, and a thin silicon steel sheet is wound around the outer periphery of the core body to form a yoke part 37. Then, the bearing 39 is fixed to the motor case 38 and the bearing 39 attached to the rotating shaft 30 is attached to the motor case 38.

FIG. 10 is a perspective view showing the structure of a modified example of the core body according to the present invention. Slot portion 40 between flange portion 40a and leg portion 40b of bracket 40
Two flat plates 41 and 42 are attached to c in parallel along the central axis direction, and two parallel flat plates 41 and 4
The magnetic pole plate 43 is fitted between the two. After mounting, the coils are mounted on the parallel flat plates 42 and 43. The magnetic pole plate 43 has an inner end 43 facing the rotor.
Arc-shaped flanges are formed on each of the outer ends 43b that a and the yoke abut, and a slot portion 43c for mounting a coil is formed between these flanges, so that the magnetic pole plates 43 can be easily aligned and supported. This eliminates the need for a shaft used to bundle the magnetic pole plates, and also eliminates the work of aligning the magnetic pole plates. The configuration as in this example is particularly effective in assembling a multipolar motor.

It should be noted that the present invention is not limited to the above-described embodiments, and can be modified and modified in many ways. For example, in the above-described embodiment, the magnetic pole plate constituting the magnetic pole portion is made of a silicon steel plate, but it is not limited to a silicon steel plate, and other high magnetic materials such as magnetic permeability can also be used. In addition, in the above embodiment, a shaft with a circular cross section was used as the magnetic shaft to align and support the magnetic pole plates, but if a shaft with a polygonal cross section is used, the magnetic pole plates can be aligned accurately with a single shaft. can be supported, and the step of aligning the pole plates can be omitted. Furthermore, although the yoke part is constructed by winding a thin silicon steel sheet, it can also be constructed by winding a magnetic wire with high magnetic permeability, or the yoke can be constructed by inserting the core body into a cylindrical sleeve made of magnetic material. It can also constitute a section. In the latter case, the cylinder can also be constructed by combining two semi-cylindrical parts.

(Effects of the Invention) As explained above, according to the present invention, the magnetic pole part and the yoke part are constructed as separate structures, and the yoke part is formed after the coil is attached to the magnetic pole part, so that the work is easy. The coils can be mounted on the motor, making it easier to assemble the stator and using an automatic coil winding machine, making it possible to increase the number of poles of the motor and improve the volumetric efficiency without being subject to assembly restrictions.

Furthermore, after assembling the core body, each magnetic pole piece is aligned and positioned with respect to the center line of the rotor using a positioning jig, and then the magnetic sheet member is wound to form the yoke part, so the coil The installation work becomes easier, and the accuracy of assembling the magnetic pole part can be further improved.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the structure of an example of the core body of the stator according to the present invention, FIG. 2 is a plan view showing the structure of a conventional brushless motor as viewed from the axial direction, and FIG. 3 is a perspective view of the stator core body according to the present invention. A perspective view showing the state in which the bracket is removed from the core body, Figure 4A
and B is a plan view showing the configuration of an example of the magnetic pole plate;
Figure A is a front view showing the configuration of an example of the bracket, Figure B is a sectional view taken along the line -- in Figure 5A, Figure C is a back view, and Figure 6 is a plan view showing the configuration of an example of the positioning jig. , FIG. 7 is a sectional view showing the state when the core body is positioned, FIG. 8 is a sectional view taken along a plane perpendicular to the central axis line showing the state where the yoke part is attached, and FIG. 9 is a sectional view showing the stator according to the present invention. FIG. 10 is a cross-sectional view taken along a plane parallel to the median axis, showing the structure of an example of a brushless motor using the present invention, and FIG. 10 is a perspective view showing the structure of a modified example of the core body according to the present invention. 10... Core body, 11, 33... Magnetic pole part, 1
2, 35, 40...Bracket, 13, 14, 3
4, 43...Magnetic pole plate, 15...Shaft, 16...
...Positioning jig, 17...Press member, 18...
Washer, 19... Nut, 20, 37... Yoke part, 21, 36... Coil, 30... Rotating shaft, 3
1... Permanent magnet, 32... Stator, 38... Motor case, 39... Bearing, 41, 42...
...Parallel plate.

Claims (1)

[Claims] 1. In manufacturing a stator for a brushless motor, a large number of magnetic pole plates 13 and 14 are laminated to form a plurality of magnetic pole parts 11 made up of magnetic pole plate rows, and these plurality of magnetic pole parts 11 are stacked with a pair of magnetic pole parts 11 made of a non-magnetic material. The core body 10 is assembled by being arranged between the fixing members 12 at equal intervals around the central axis of the rotor and integrally supported, and a positioning jig 16 having a circular outer outline is installed in the center of the core body 10. The positioning jig 11 is inserted into the inner peripheral surface of the core body 10 by pressing each magnetic pole part 11 from its outer periphery toward the axial center.
Align and position the magnetic pole plates so that they are in contact with the outer peripheral surface of the
A method for manufacturing a stator for a brushless motor, characterized in that, after a coil 21 is attached to each of the magnetic pole parts 11, a yoke part 20 is formed by wrapping a sheet made of a magnetic material around the outer periphery of the core body.