JP2001037116A - Stator core of rotating machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the waste of a core material and to achieve improved material punching by allowing the tip face of a magnetic pole tooth to retreat to the outside of a shape being displaced to the minimum gap outer diameter side required for punching within a range opposing the slot of an outer annular member. SOLUTION: The stator core is fixed by combining an inner member and an outer annular member 26, and the inner member is formed by integrating the inner annular part and 18 magnetic pole teeth 30 with the same shape projecting radially with an equal interval from the inner annular part to the outside. A width (a) of a tip face 30A of the magnetic pole teeth 30 of the inner member is smaller than an opening width (b) of a slot. Also, a retreated part (d) being collapsed in the direction of an outer diameter with a center in a range (c) opposing a slot as a center is formed on the inner-periphery surface of the outer annular member 26. Distance from the center of the rotor of the retreated part (d) is located at a dimension outer-diameter side being equivalent to the amount of minimum gap at least required for punching as compared with the tip face 30A of the magnetic pole teeth 30.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stator core of a rotary motor having a plurality of identically shaped magnetic pole teeth for winding a stator coil.

[0002]

2. Description of the Related Art A permanent magnet type DC rotary motor having a permanent magnet for a rotor and a stator coil for a stator is known. Also in various DC motors, AC motors or generators,
2. Description of the Related Art There is known an apparatus using a stator on which a stator coil is wound. Here, the stator core serving as the magnetic core of the stator is formed by laminating and fixing a large number of punched plates obtained by punching a silicon thin steel plate as a magnetic core material thin plate.

As such a stator, a stator core having magnetic pole teeth projecting inward from a generally cylindrical portion is used. Then, the stator coil is wound so as to fit in slots (grooves) between the magnetic pole teeth. In this case, the slot is open from the space between the magnetic pole teeth toward the inner diameter side. For this reason, the stator coil must be wound around each magnetic pole tooth from the inner diameter side of the stator core, and there has been a problem that workability is extremely poor and productivity is poor. Also, it becomes difficult to load the coil densely in the slot,
The space factor (the ratio of the coil cross-sectional area to the slot cross-sectional area) also decreases.

[0004] Therefore, it has been proposed to divide the stator core into two members. That is, it is divided into an inner member in which the magnetic pole teeth project radially outward from the inner annular portion, and an outer annular member surrounding the outer periphery of the inner member. In this case, since the magnetic pole teeth of the inner member protrude outward, the slots between the magnetic poles also open outward. Therefore, the workability when winding the stator coil around the slot is improved, and the space factor can be increased. After winding the stator coil in this way, the inner member is inserted into the outer annular member.

[0005]

Here, the process of punching the inner member and the outer annular member into a predetermined shape is to finish the die hole to a correct shape and size, and to make the punch only a certain amount of clearance (clearance) from the die hole. A member having a required shape is cut out from a thin steel plate sandwiched between a die and a punch. As described above, in the punching process, it is necessary to provide a clearance amount along the outer periphery of a required shape.

On the other hand, if a gap is formed between the outer annular member and the tip end surfaces of the magnetic pole teeth or the adhesion between them is incomplete, the resistance (magnetic resistance) of the path (magnetic path) through which the magnetic flux passes increases, resulting in loss. And the efficiency becomes worse. However, if the gap is too small, the inner member and the outer annular member cannot be fitted. Therefore, an optimum gap is set, but this optimum gap is generally smaller than the clearance required for the above-described punching.

As described above, since the optimum gap is generally smaller than the clearance required for the punching (optimum clearance <clearance), the inner member and the outer annular member must be punched from separate thin steel plates. If the relationship between the optimum gap and the clearance is opposite (optimal clearance> clearance), the inner member can be molded inside the outer annular member and punched out. Can not. For this reason, there is a problem that the material inside the outer annular member cannot be used, and the waste of the material increases.

The present invention has been made in view of the above circumstances, and divides a stator core into an inner member and an outer annular member to facilitate winding of a stator coil.
When the inner member and the outer annular member are formed by punching and laminating a thin plate of a magnetic core material, it is an object of the present invention to provide a stator core of a rotating machine capable of reducing waste of the magnetic core material and facilitating material removal. And

[0009]

According to the present invention, an object of the present invention is to laminate a punched plate formed by punching a thin sheet of a magnetic core material into a predetermined shape, and to wind a stator coil around a plurality of magnetic pole teeth facing the outer peripheral surface of the rotor. In the stator core of the rotating machine, an inner member integrally formed with a plurality of magnetic pole teeth of the same shape protruding outward at equal intervals radially from an inner annular portion surrounding the outer periphery of the rotor while keeping an air gap, and each magnetic pole An outer annular member that is in close contact with the outer distal end surface of the tooth, wherein the width of the distal end surface of each magnetic pole tooth is smaller than the opening width of a slot formed between two magnetic pole teeth, A rotating machine provided with a retreating portion located on an outer diameter side of a shape in which at least a tip end surface of the magnetic pole teeth is displaced to an outer diameter side in a range facing a slot at least a minimum clearance required for punching; The stator core is achieved by.

[0010]

FIG. 1 is a sectional view of a main part of a permanent magnet type DC rotary motor according to an embodiment of the present invention, FIG. 2 is an enlarged view of a portion viewed from an arrow II, and FIG. 3 is a diagram showing an inner member of the stator core. FIG. 4 is a view showing the outer annular member, and FIG.
And (B) are sectional views taken along lines AA and BB in FIGS. 3 and 4, respectively, and FIG. 6 is a view showing material removal during punching. This motor uses a permanent magnet for the rotor 10 (rotor) and forms a rotating magnetic field on the stator 12.

The rotor 10 includes a cylinder 14 held on a rotating shaft (not shown), a rotor core 16 fitted on the outer periphery of the cylinder 14, and twelve permanent magnets 18 fixed to the rotor core 16. Have. The rotor core 16 is formed by punching a silicon thin steel plate into a substantially annular shape and laminating the same in the longitudinal direction of the cylinder 14. Here, twelve voids 20 which are wide in the circumferential direction and thin in the radial direction are formed at equal intervals in the rotor core 16.

The permanent magnets 18 are made of, for example, a sintered type neodymium / iron / boron magnet in a plate shape. Note that the width of the permanent magnet 18 is
Is smaller than the width of the permanent magnet 18 in the gap 20.
A gap is left on both sides of the permanent magnet 18 when cooling air is loaded.

The stator 12 has a stator core 22 and a stator coil (not shown). Stator core 2
Reference numeral 2 denotes a combination of the inner member 24 and the outer annular member 26, which is fixed. Here, the inner member 24 and the outer annular member 26 are formed by laminating and punching silicon thin steel plates similarly to the rotor core 16.

The inner member 24 has an inner annular portion 28, and 1 radially protrudes outward from the inner annular portion 28 at equal intervals.
It is formed by integrally forming eight magnetic pole teeth 30 having the same shape. The inner diameter of the inner annular portion 28 is slightly larger than the outer diameter of the rotor 10, and a small gap, that is, an air gap 32 (FIGS. 1 and 2) is formed therebetween.

A stator coil (not shown) is wound around each magnetic pole tooth 30. That is, the stator coil has magnetic pole teeth 3
0 is loaded in a slot (groove) 34 formed between the two. After the slots 34 have been loaded with stator coils, the inner member 24 is inserted into the outer annular member 26 and
Is assembled in the state shown in FIG.

As shown in FIGS. 2 and 6, a substantially trapezoidal projection 30B is formed on the tip end surface 30A of the magnetic pole teeth 30 of the inner member 24. On the inner peripheral surface of the outer environment member 26, a concave portion 26A into which the distal end surface 30A of the magnetic pole tooth 30 is engaged is formed. The width a (width in the circumferential direction) of the magnetic pole teeth 30 is smaller than the opening width b of the slot 34.

The inner peripheral surface of the outer annular member 26 is formed with a recessed portion d which is depressed in the outer radial direction with the center in the area c facing the slot 34 as the center. The distance of the retreat portion d from the center A (FIG. 1) of the rotor 10, that is, the position in the radial direction, is at least smaller than the tip end surface 30A of the magnetic pole teeth 30 and corresponds to the minimum clearance required for punching. Located in. That is, this retreat part d
It is located on the outer diameter side than the shape in which the tip surface 30A is displaced toward the outer diameter side by the minimum clearance. Therefore, when the inner member 24 is rotated by an angle (10 °) that is half the pitch (360 ° / 18 = 20 °) of the magnetic pole teeth 30, the tip surface 3 of the magnetic pole teeth 30
0A faces the retreat portion d.

At this time, a gap larger than the minimum clearance is formed between the distal end face 30A and the receding portion d. For this reason, the inner member 24 and the outer annular member 26 can be arranged at such a position to perform molding on a thin plate of the magnetic core material. By performing a punching process using a punching die and a punch manufactured so as to form the die, material waste can be reduced. That is, the inner member 24 can be modeled using the inside of the circular shape of the outer annular member 26. In FIGS. 3 and 4, reference numerals 36 and 38 denote projections and depressions used for positioning when laminating the punched plates, and are called half piercings. The irregularities 36 and 38 are pressed at the same time as the punching.

In this embodiment, the center of the recessed portion d formed on the inner peripheral surface of the outer annular member 26 coincides with the center of the slot 34. Therefore, as shown in FIG. 6, the inner member 24 was placed at a position where the magnetic pole teeth 30 were rotated by a half pitch (10 °), and material was removed. However, the center of the recessed portion d may be deviated from the center of the slot 34, and the inner member 24 may be rotated by an angle other than half a pitch to perform material removal.
At this time, it is needless to say that a gap with a minimum clearance or more is formed between the distal end surface 30A of the magnetic pole teeth 30 and the inner peripheral surface of the outer annular member 26.

In the above embodiment, the present invention is applied to a permanent magnet DC motor. However, the present invention is applicable to other types of motors such as induction motors and generators as long as they have a stator having a coil. The present invention includes these.

[0021]

As described above, according to the first aspect of the present invention, when a stator core is formed by stacking punched plates obtained by punching a thin magnetic core material, the stator core is formed at equal intervals from the inner annular portion to the outer side. An inner member integrally formed with magnetic pole teeth of the same shape protruding radially, and an outer annular member, the width of the tip surface of each magnetic pole tooth is made smaller than the opening width of the slot, and the outer annular member has a slot. Within the opposing range,
Since the tip surface of the magnetic pole teeth is retracted at least to the outside of the shape in which the minimum clearance required for punching is shifted to the outer diameter side, material removal of the inner member using the inner portion of the outer annular member And the waste of the thin plate of the magnetic core material is reduced. Therefore, the material can be effectively used.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part of an embodiment of the present invention.

FIG. 2 is an enlarged view of a part viewed from an arrow II in FIG. 1;

FIG. 3 is a view showing an inner member of a stator core;

FIG. 4 shows an outer annular member.

FIG. 5 is a sectional view taken along lines AA and BB in FIGS.

FIG. 6 is a diagram showing material removal in a punching process.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Rotor 12 Stator 22 Stator core 24 Inner member 26 Outer annular member 28 Inner annular 30 Magnetic pole tooth 30A Tip surface 34 Slot a Width of magnetic pole tooth b Slot opening width c Range opposed to slot of outer annular member d Retracted portion

Claims (1)

[Claims] 1. A stator core of a rotating machine formed by laminating punched plates obtained by punching a magnetic core material thin plate into a predetermined shape and enabling a stator coil to be wound around a plurality of magnetic pole teeth facing the outer peripheral surface of a rotor. An inner member integrally formed with a plurality of magnetic pole teeth of the same shape protruding outward at equal intervals radially from an inner annular portion surrounding the outer periphery of the rotor while maintaining an air gap, and an outer surface closely contacting the outer tip surface of each magnetic pole tooth An annular member, wherein the width of the tip end face of each of the magnetic pole teeth is smaller than the opening width of a slot formed between two magnetic pole teeth, and the magnetic pole is located within a range opposed to the slot of the outer annular member. A stator core for a rotating machine, comprising: a retreating portion which is located on an outer diameter side of a shape in which a tip end surface of a tooth is at least displaced to an outer diameter side by a minimum clearance required for punching.