JPH04304151A - Motor - Google Patents

Abstract

PURPOSE:To obtain a motor in which a static cogging can be effectively reduced, by varying relative positions of a plurality of slots for forming a core and a plurality of poles for forming a magnet at different angles at each of the plurality of slots. CONSTITUTION:Slots U1, U2, V1, V2, W1, W2 are formed at positions deviated at predetermined angles at the angles of the two slots U1 and U2, V1 and V2, and W1 and W2 for forming phases U, V, W from positions equally divided from 360 deg. by six in a rotating direction. Accordingly, the slots becoming the same positional relationship of the positional relationships of the slots and the magnet 3 are eliminated, thereby reducing a static cogging to be generated in response to the positional relationship of the magnetic field of the magnet 3 and the slots.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor, and is particularly suitable for application to a motor having an iron core.

0002

2. Description of the Related Art Conventionally, as shown in FIG. 4, a motor with an iron core is composed of an iron core 4 provided on the stator side and a rotor magnet 3 connected to a rotating shaft 5. , each slot U1, U2, V1 of the iron core 4,
A winding 7 is wound around V2, W1, and W2, respectively.

[0003] This iron core 4 has a slot U forming the first phase.
1 and U2, and slots V1 and V2 forming the second phase.
, and slots W1 and W2 forming the third phase, resulting in a 3-phase, 6-slot configuration, and an 8-pole magnet 3 on the rotor side.

Therefore, the magnet 3 can be driven to rotate by applying a drive current to the windings 7 wound in the slots of the first, second and third phases in a predetermined order. .

[0005]

[Problems to be Solved by the Invention] In this type of motor 1, as a method of reducing the rotational load at the time of starting rotation, which is called static cogging, the iron core is moved in a direction parallel to the rotation shaft 5. There is a method of skewing it in a spiral shape with the center as the center.

However, in a motor using an iron core with such a skew structure, it is difficult to install a rotation detection element such as a Hall element between each slot of the iron core, and in a thin motor, it is difficult to install a rotation detection element such as a Hall element. There was a problem in that the skew angle could not be obtained and it was difficult to reduce static cogging to a practically sufficient range.

The present invention has been made in consideration of the above points, and it is an object of the present invention to propose a motor that can more effectively reduce static cogging.

[0008]

[Means for Solving the Problems] In order to solve this problem, in the present invention, in a motor 10 having an iron core 14 and a magnet 3 provided at positions facing each other, a plurality of slots U1 forming the iron core 14 are provided. , U2, V1
, V2, W1, W2 and the relative positions of the plurality of magnetic poles forming the magnet 3, respectively, in the plurality of slots U1, U.
2. V1, V2, W1, and W2 are changed by different angles X, respectively.

[0009]

[Operation] The relative positional relationship between the slots U1, U2, V1, V2, W1, W2 of the iron core 14 and the magnet 3, which are provided at positions facing each other, is determined by the slots U1, U, and the magnet 3.
2. By shifting V1, V2, W1, and W2 by different angles, each pole of magnet 3 and each slot U
1, U2, V1, V2, W1, and W2 can be prevented from having the same positional relationship, thereby making it possible to further effectively reduce static cogging caused by the magnetic field of the magnet 3.

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings.

In FIG. 1, in which parts corresponding to those in FIG. W phase) respectively have two slots U1 and U2, V1 and V2,
It is formed by W1 and W2.

Each of the six slots U1, U2, V1, V2
, W1, and W2 are two slots U1 and U2, V1 and V2, and W1 and W2 that form each phase for each phase U, V, and W from a position that divides 360° into six in the rotation direction. The angles are respectively formed at positions shifted by predetermined angles.

That is, the angles of the slots U1 and U2 forming the first phase are deviated by a deviation angle X from the case where the slots U1 and U2 are formed at equal intervals (FIG. 4). Further, the angles of the slots V1 and V2 forming the second phase are deviated by a deviation angle X from the case where the slots V1 and V2 are formed at equal intervals (FIG. 4). Furthermore, the angles of the slots W1 and W2 forming the third phase are deviated by a deviation angle X from the case where the slots W1 and W2 are formed at equal intervals (FIG. 4).

[0014] This deviation angle X [°] is 3 phase, 4n pole, 3
In a motor with n slots (n = 2, 3, ...), numbers 1 to n are assigned appropriately to the slots in the same phase, and the number assigned to each slot is set to k, using the following formula.

[Math 1] It is determined by

In this embodiment, the motor 10 has three phases and eight
Due to the pole and 6 slot configuration, n=2,
Further, by assigning numbers Uk, Vk, and Wk as shown in FIG. 2(A) to each slot, the position of each slot becomes as shown in FIG. 2(A) based on equation (1).

That is, in this case, slots U1, V1, and W1, where k=1, are shifted by -3.75°, and slots U2, V2, and W2, where k=2, are shifted by +3.75° (however, (+) (in the clockwise direction in FIG. 2(A)).

In the above configuration, the motor 10 is shown in FIG.
As shown in A) to (F), each slot U1, U2, V1
, V2, W1, W2, and the positional relationship of each pole of the magnet 3 differs by a fixed angle for each slot.

Therefore, slots U1, U2, V1, V2,
Among the positional relationships between W1, W2, and the magnets 3, since there are no slots that have the same positional relationship, static cogging that occurs depending on the magnetic field of the magnet 3 and the positional relationship between the slots can be reduced.

Furthermore, by using skew of the magnetization pattern in combination, static cogging can be sufficiently reduced by slightly skewing the iron core 14, thereby effectively reducing static cogging even in a thin motor. obtain.

According to the above configuration, static cogging can be further effectively reduced by shifting the positional relationship between each slot and the magnet by a different angle for each slot.

By shifting the slot angles, it is possible to secure a mounting location for a sensor such as a rotation detecting element between the widely spaced slots.

In the above embodiment, the method of allocating the number k to each slot Uk, Vk, and Wk was described as shown in FIG. 2(A), but the present invention is not limited to this. 2(B) may be used. In this case, each slot may be shifted by a shift angle X (based on equation (1)) in a predetermined direction in accordance with its number k.

Furthermore, in the above embodiment, the present invention was applied to a 3-phase, 8-pole, 6-slot motor 10, but the present invention is not limited to this.
It can be widely applied to motors satisfying 3n slots (n=2, 3, . . . ).

[0024]

As described above, according to the present invention, the positional relationship between the plurality of slots that form the iron core and the magnetic poles of the magnet are shifted by different angles for each slot, thereby making it possible to achieve static even more effectively. A motor that can reduce cogging can be realized.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of a motor according to the present invention.

FIG. 2 is a schematic diagram showing how slots are formed according to the present invention.

FIG. 3 is a schematic diagram showing the positional relationship between a magnet and a slot.

FIG. 4 is a sectional view showing a conventional example.

[Explanation of symbols]

1, 10...Motor, 3...Magnet, 4, 14...
Iron core, 5... Rotating shaft, 7... Winding wire, U1, U2, V1,
V2, W1, W2...slot.

Claims (1)

[Claims] Claims: 1. A motor having an iron core and a magnet provided at positions facing each other, wherein the relative positions of each of a plurality of slots forming the iron core and a plurality of magnetic poles forming the magnet are determined by adjusting the relative positions of each of the plurality of slots forming the iron core and the plurality of magnetic poles forming the magnet. A motor characterized in that each slot changes a different angle.