JPS59178942A - Assembling method of brushless motor - Google Patents

Abstract

PURPOSE:To strongly magnetize by laminating thin magnetic iron plates having recesses, to which 2P pieces of alnico magnets are inserted to hold the magnets, and inserting the magnets to a stator while a magnetizing coil is wound in the recess formed on the side disc. CONSTITUTION:Thin magnetic ion plates 20 having recesses 19' capable of containing 2P pieces of alnico magnets 19 are laminated in the prescried number and engaged with a rotational shaft 18. Side plates 23 (24) having recesses 21, 22 are contacted radially of the magnets 19 at both sides of the laminated core, a bolt 25 is passed via a through hole 25' formed previously, and integrally molded to form a rotor 26. Then, after magnetizing oil 27 is wound in the recesses 21, 22, the rotor 26 is inserted to the stator, not shown, the coil 27 is energized and magnetized, and is removed. In this manner, the magnets are magnetized in high permeance, thereby manufacturing a motor of high performance.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method of assembling a brushless electric motor used as a drive source for machine tools, robots, etc.

The configuration of conventional examples and their problems In recent years, automation of factories has progressed, and Tm machines used in factories,
There is an urgent need to improve the reliability of robots, etc. Conventionally, DC servo motors with relatively internal control circuits have been used as drive sources for this type of machine tools, robots, etc., but because they have electric contacts such as brushes and commutators, they are unreliable and have limited dimensions and dimensions. Maintenance and inspection of the motor, such as replacing brushes and cleaning brush powder, is essential, and there is also the problem of deterioration of insulation resistance due to adhesion of brush powder. Therefore, recently, brushless motors without brushes or commutators have been attracting attention, although their control circuits are somewhat more complex.As semiconductor integrated circuit technology has progressed, complex control circuits have become cheaper, and DC servo motors have been replaced by brushless motors. There is a tendency to try.

In principle, a brushless electric motor consists of a rotor made of permanent magnets, but in order to design a small, high-performance electric motor, it is necessary to use a magnet with a high operating magnetic flux density, such as an alnico magnet, as a permanent magnet. is desirable. However, this type of magnet has a small coercive force, so if the length of the magnet in the magnetization direction is short, there is a problem that it is easily demagnetized by the magnetic flux density on the field side. Therefore, in order to obtain the maximum torque, it is necessary to make the magnet length as long as possible.In general, there is a method of arranging the magnetization direction of the magnet in a direction tangent to the concentric circle of the rotor axis.

A conventional brushless electric motor will be explained below. 1st
The figure shows the structure of a conventional brushless electric motor.
1 is a stator core around which the armature winding 2 is wound; 3 is a frame that holds the stator core 1; 4.5 is a bracket that holds the rotor shaft 8 via bearings 6 and 7; 9 is a bracket that holds the rotor shaft 8 through bearings 6 and 7; 010, which is a rotor position detector that detects the timing of supplying power to the armature winding 2, is a rotor fixed to the rotor shaft 8;
As shown in FIG. 2, the rotor core 12 is made up of electrical iron plates laminated to a predetermined thickness into which alnico magnets 11 are inserted and held. This rotor core 12 is fixed to side plates 14 and 15 with bolts 13.

However, in this type of rotor 8, the Danopper winding 16 is formed by outsert molding of aluminum, etc., so when the rotor 8 is inserted into the identifier, the coil wire to be magnetized is inserted in this state. There is no gap 2. Therefore, as shown in Fig. 3, after the rotor 10 is assembled and magnetized, the magnet is removed from the magnetizer 1a and inserted into the stator. ing. However, in the conventional magnetization method described in Section 2, the magnetic circuit is opened when the rotor 10 is taken out from the magnetizer and inserted into the stator, and the demagnetization curve of the alnico magnet shown in Figure 4 The operating point of the magnet at the time of magnetization drops from point A to point B when Bamianos is low, and the operating point of the magnet moves to point 0 when inserted into the stator.

In other words, depending on the rotor structure, the operating point is 10
The state will be such that the magnet will be demagnetized to 30 to 30. In particular, there has been a problem that the lower the hermia/s of the magnetic circuit of the rotor 10 alone, the more severe the demagnetization effect becomes.

Purpose of the Invention The present invention solves the above-mentioned conventional problems, and provides a high-performance branless electric motor that enables magnetization with the rotor inserted into the stator and makes maximum use of the characteristics of alnico magnets. The entire purpose is to do so.

Structure of the Invention The present invention has a structure in which 2P alnico magnets are sandwiched, and the separately formed 2P salient poles are held between two side disk rings and fixed to an integral body by tightening bolts. , a space is created between the salient poles to insert the magnetizing coil, and four parts into which the magnetizing coil is inserted are provided at least on the outer periphery of the two side disc rings, and the magnetizing winding is attached to the rotor. After magnetization, the magnet is inserted into a stator, the magnetization wire is magnetized by passing a current through it, and then the magnetization wire is removed, thereby making it possible to attach a magnet with high harmiance, thereby providing a brushless motor with high let performance. It is.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. Fifth
The figure is a half-cut sectional view of the rotor of the present invention, and its structure will be explained together with an assembly method. 18 is L “trochanter [l1lII
The salient pole is a 2P pole made by laminating thin iron plates made of magnetic material with a predetermined thickness in the 1l11 direction. 2o, non-magnetic V1', outer peripheral part VC
The four parts 21 are made of side disk rings 23 and 24 (24 not shown) each having 2P recesses 21 and 2P recesses 22 on the inner circumference.
．． 22 is placed at the magnet position (in the axial direction r (
A rotor 26 is constructed by clamping and tightening bolts 25i/7c passing through the side disc rings 23, 24 and the salient pole 2o at the same time. The rotor 26VC magnetizing coil 2
7 is inserted into the recesses 21 and 22 of the side disc rings 23 and 24 and wound around it, placed inside the armature which is a stator, and after passing a current through the magnetizing coil 27, Remove 27.

According to this embodiment configured as above, since the salient poles 20 are formed separately, a space is created for inserting the magnetizing coil 27, and a space for inserting the magnetizing coil 27 is created in the side disc rings 23 and 24. Since the recesses 21 and 22 are provided, the magnetizing coil 2a can be inserted and wound, and the rotor 26 can be inserted into the stator and magnetized. For this reason, it is possible to magnetize the magnet with a high pemance at point D shown in No.44.Furthermore, in conventional rotors, the salient poles were mechanically coupled, so magnetic flux leakage within the rotor was prevented. However, since the rotor of the present invention magnetically separates the salient poles, the leakage magnetic flux of the magnet can be reduced, and the performance of the magnet can be maximized. There is also a big effect that it can be done.

FIG. 6 shows another embodiment of the present invention, which differs from the embodiment shown in FIG. This means that the method was applied only to the outer periphery.

According to this embodiment, the recess 22 is not required on the inner circumference of the side disc rings 23, 24. Furthermore, since there is no need for a gap in which the magnetizing coil ♀7 is inserted in the portion of the magnet facing the rotor shaft 18, there is a great effect that the width of the magnet 190 can be increased as shown by the dashed line in FIG. Further, since the magnetizing coil 27 only needs to be wound around the outer periphery, there is a great effect that winding is easy.

Effects of the Invention The present invention clamps a separated 2P salient pole holding 2P magnets with a side disk ring with a recess in the inner and outer periphery, or only in the outer periphery. Since the magnetizing coil is fixed in one piece, it is possible to wrap the magnetizing coil around the entire rotor, and magnetization is possible with the rotor inserted into the stator.
It is possible to obtain the effect that the operating point of the alnico magnet can be set high.

[Brief explanation of the drawing]

Fig. 1 is a half-cut sectional view of a brushless motor, Fig. 2 is a sectional view of a conventional rotor, Fig. 3 is a principle diagram of a magnetizing machine for a conventional brushless motor, and Fig. 4 explains the operating point of a magnet. The magnet demagnetization curve diagrams, FIGS. 5 and 6, are half-mounted sectional views of the rotor according to the present invention. 18゛...Rotor shaft, 19...Alnico magnet,
20-- salient pole, 21, 22°... recess, 23.242° side disc ring, 25-- bolt, 261° rotor, 27° '° magnetizing coil. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 3 Illustrated report Kei (＼)
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Claims (1)

[Scope of Claims] 1) A stator with an armature winding, and a 2P salient pole made by laminating thin iron plates made of magnetic material with a predetermined thickness in the axial direction;
Consists of 2P high-operating magnetic flux density magnets with magnetization direction characteristics in the direction tangent to the concentric circle of the rotor shaft, and 2 non-magnetic materials with 2P recesses equally spaced on the outer and inner peripheries. (111 disc ring), the magnet is held between the salient poles in the circumferential direction, the side disc ring is arranged so that the recessed part of the side disc ring is located at the magnet part position, and the salient pole is clamped in the axial direction, and the fixed rotor is press-fitted onto the rotor shaft and tightened with bolts that pass through the side disc ring and the salient pole at the same time. Brushless motor assembly method 0 in which a magnetizing coil is wound, then inserted into an armature that is a stator, a current is passed through the magnetizing coil, and the magnetizing coil is removed. 2) Armature A stator with windings, a 2P salient pole made by laminating thin iron plates made of magnetic material with a predetermined thickness in the axial direction,
A side disc ring made of 2P magnets with high operating magnetic flux density and having magnetization direction characteristics in the direction tangent to the concentric circle of the rotor shaft, and 2 non-magnetic materials with 2P four parts arranged at equal intervals on the outer periphery. The magnet is held between the salient poles in the circumferential direction, and the side disk ring is arranged so that the concave portion of the side disk ring is located at the magnet portion, and the salient pole is held in the axial direction. death,
The fixed rotor is press-fitted onto the rotor shaft by tightening with bolts that pass through the side disc ring and the ultimate at the same time, and after winding a magnetizing coil between the four parts of the side disc ring, the stator is fixed. A method of assembling a brushless motor, in which the brushless motor is inserted into an armature, then a current is passed through the magnetizing coil, and then the magnetizing coil is removed.