JPH06253515A - Rotor for self-starting permanent magnet type synchronous motor - Google Patents

Abstract

PURPOSE:To enhance reliability of rotor by making stop grooves oppositely in the outer periphery of rotor core and the inner periphery of permanent magnet, fitting flexible stop members in the grooves and filling the grooves with a filler, thereby securing the permanent magnet rigidly. CONSTITUTION:Stop grooves 4 are made oppositely in the outer periphery of a rotor core l and the inner periphery of a permanent magnet 3 and stop members 5 are fit in the stop grooves 4. Adhesive is provided on the bonding faces of the rotor core 1 and the permanent magnet 3 and in the stop grooves 4. The stop grooves 4 are skewed because the core is skewed but since the stop member 5 is made of flexible resin or metal, it can be fit in the skewed stop groove 4 while being bent. Furthermore, the flexible stop member 5 minimizes the gap with respect to the stop groove 4 thus eliminating play at the stop part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a rotor of a self-starting permanent magnet type synchronous motor used for general industries and others.

[0002]

2. Description of the Related Art Self-starting permanent magnet type synchronous motors have been widely used from the viewpoint of constant speed drivability, high efficiency and high power factor, and various studies have been made on the structure of their rotors. There is.

An example of the structure of a conventional rotor will be described with reference to FIG. FIG. 3 is a vertical cross-sectional view perpendicular to the axis of the rotor, and 1 is a rotor core in which cores are skewed and stacked. Reference numeral 2 denotes a starting secondary conductor that is die-cast with the rotor core 1 and forms a short-circuit ring (not shown) at both ends of the rotor core 1. Reference numeral 3 denotes a cylindrical permanent magnet, which is fixed to the rotor core 1 with an adhesive.

The operation of the self-starting permanent magnet type synchronous motor having the rotor configured as described above will be described.

When AC power is applied to the armature winding (not shown) of the stator, a rotating magnetic field is generated, and this magnetic flux is linked to the starting secondary conductor 2 of the rotor, whereby An induced current flows, interacts with the rotating magnetic field, generates torque, and starts rotating. That is, the electric motor starts as an induction motor.

Subsequently, when the number of revolutions reaches near the synchronous speed,
The rotor is drawn to the synchronous speed by the magnetic poles created by the permanent magnet 3, and thereafter, the synchronous operation is performed in synchronization with the power supply frequency.

Since the present synchronous motor has a magnetic flux generated by the permanent magnets 3, it does not require exciting power, so that high efficiency and power factor can be obtained, and the rotation speed is always synchronized with the power supply frequency even if the load changes. It has excellent advantages such as constant speed operation.

[0008]

However, in the above configuration, since the permanent magnet 3 is fixed to the rotor core 1 only by the adhesive, the permanent magnet 3 is adhered due to deterioration of the adhesive or defective work of applying the adhesive. When the force is reduced, and especially when the impact load or the overload is repeatedly applied, the permanent magnet 3 may slip and rattling may occur, and the reliability may be uncertain.

Therefore, as a solution to the above problem, a protrusion is provided on the outer circumference of the core of the rotor core 1 to serve as a locking portion, and a groove to be fitted therein is provided on the inner circumference of the permanent magnet 3 for engagement. If it is made possible and then fixed using an adhesive, it is considered that the reliability of fixing the permanent magnet 3 can be improved.

However, since the core of the rotor core 1 is skewed and laminated in order to suppress torque pulsation and noise vibration at the time of starting, the locking portion as described above should also be skewed. Becomes Therefore, it is necessary to skew the groove on the inner circumference of the permanent magnet 3 for fitting it, but it is difficult to mold the groove on the inner circumference of the permanent magnet 3 so that it can fit into the locking portion without a gap. It is also very difficult to fit the permanent magnet 3 into the rotor core 1 in terms of work. If you try to make these easy,
The inner circumferential groove of the permanent magnet 3 may be made sufficiently larger than the locking portion of the rotor core 1, but the gap between the two becomes large and even if there is a locking portion, it is practically possible to fix only the adhesive. It is not possible to eliminate the anxiety that rattling will occur. Therefore, under the present circumstances, the fixing of the rotor core 1 and the permanent magnet 3 in which the cores are skew-stacked depends only on the adhesive force of the adhesive.

In view of the above, the present invention provides a reliable rotor by forming a locking portion between the skew-stacked rotor core and the permanent magnet to firmly and securely fix the permanent magnet. It is the one we are trying to provide.

[0012]

In order to solve the above-mentioned problems, the rotor of the present invention has a rotor core formed by stacking skewed cores and arranging a secondary conductor for starting. A cylindrical permanent magnet fixed to the outer circumference of the child core with an adhesive or other fixing means, and provided with locking grooves facing the outer circumference of the rotor core and the inner circumference of the permanent magnet, respectively. The permanent and secure permanent magnet is fixed by fitting and inserting a flexible locking member into the locking groove.

The same purpose can be achieved by filling the locking groove with a filling material to form a locking member.

[0014]

According to the present invention, since the locking member can be engaged with the skewed locking groove without any gaps by the above-described structure, the locking member is strong and reliable in combination with the adhesive and other fixing means. The permanent magnet can be fixed easily, and the reliability of the rotor can be improved.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A rotor according to a first embodiment of the present invention will be described below with reference to FIG.

FIG. 1 is a vertical sectional view of the rotor of the present invention in a direction perpendicular to the axis thereof. The basic configuration and operation are the same as those of the conventional example described above, the same parts as those in FIG. 3 showing the conventional example are denoted by the same reference numerals, and the description of the overlapping portions will be omitted.

In FIG. 1, 4 is a locking groove provided so as to face the outer circumference of the core of the rotor core 1 and the inner circumference of the permanent magnet 3, and 5 is a locking member fitted and inserted in the locking groove 4. Is.

An adhesive is applied to the joint surface between the stator core 1 and the permanent magnet 3 and the engaging groove 4 for assembly.

Since the core is skewed and laminated, the locking groove 4 is also skewed and formed, but the locking member 5 is made of a flexible resin or metal. Therefore, it is possible to fit and insert while bending along the skewed locking groove 4. Moreover, since the locking member 5 is flexible, the gap between the locking member 4 and the locking groove 4 can be made small, so that rattling does not occur at the locking portion.

As described above, in the first embodiment,
Since the permanent magnet 3 is fixed by the adhesive in addition to the fixing force by the adhesive, the permanent magnet 3 can be fixed more firmly and surely than the conventional example, and the reliability of the rotor can be improved.

Next, FIG. 2 is a vertical sectional view of a rotor according to a second embodiment of the present invention in a direction perpendicular to the axis of the rotor.

Here, the locking member 5 is formed by filling the locking groove 4 with a filling material such as resin or light alloy. In this case, even if the locking groove 4 is skewed, the filling material is filled closely along the locking groove 4 without any clearance, so that rattling does not occur at the locking portion. Needless to say, when filling the filling material, it is necessary to give sufficient consideration to the construction method so that the filling pressure is not excessively applied to the locking groove 4 of the permanent magnet 3 and the permanent magnet 3 is damaged. Yes.

As described above, also in the second embodiment, the same effect as in the first embodiment can be obtained, and the reliability of the rotor can be improved.

[0024]

As described above, according to the present invention, the rotor core is formed by skewing the cores and laminating the secondary conductors for starting, and an adhesive or other fixing means on the outer periphery of the rotor core. And a cylindrical permanent magnet fixed to the rotor core, and a locking groove is provided so as to face the outer circumference of the core of the rotor core and the inner circumference of the permanent magnet, and a flexible locking is performed in the locking groove. Since the members are fitted and inserted and the locking groove is filled with the filling material, the permanent magnet can be firmly and surely fixed and the reliability of the rotor can be improved.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a rotor according to a first embodiment of the present invention in a direction perpendicular to an axis of a rotor.

FIG. 2 is a vertical sectional view of a rotor according to a second embodiment of the present invention in a direction perpendicular to the axis of the rotor.

FIG. 3 is a vertical sectional view in a direction perpendicular to the axis of the conventional rotor.

[Explanation of symbols]

 1 Rotor iron core 2 Secondary conductor for starting 3 Permanent magnet 4 Locking groove 5 Locking member

Claims (2)

[Claims] 1. A rotor core having skewed cores and a secondary conductor for starting, and a cylindrical permanent member fixed to the outer periphery of the rotor core with an adhesive or other fixing means. A locking groove is provided to face the outer circumference of the core of the rotor core and the inner circumference of the permanent magnet, and a flexible locking member is fitted and inserted into the locking groove. A rotor of a self-starting permanent magnet type synchronous motor characterized by the above. 2. The rotor of a self-starting permanent magnet type synchronous motor according to claim 1, wherein the locking groove is filled with a filling material.