JPS622839A - Permanent magnet field rotor for ac motor - Google Patents

Abstract

PURPOSE:To reduce the number of man-hour and reduce the cost of assembly, by organizing end plate members pressure-welded at the both ends of the laminated core of a permanent magnet field rotor, with the combined unitary body of a magnetic insulation flange plate and a stationary flange plate. CONSTITUTION:Each structure of a pair of end plate members 30, 30 on the permanent magnet field rotor 24 of an AC motor has a magnetic insulation flange plate 34 for insulation-preventing magnetic flux flow generated from the rotor 24, from leaking, and a stationary flange section 36 for fixing a stator 24 on a motor shaft 22, and the motor shaft 22 is fixed in the inner diameter slot 36a of the latter stationary flange 36 by the adequate fixing means of the key fixing method or the like. The magnetic shielding flange plate 34 is formed by punching and processing a stainless steel plate with a press machine. In the meantime, the stationary flange 36 is processed to be mass-produced with bar material of carbon steel for machine construction and by processing with a lathe or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a permanent magnet field type rotor for an AC motor, and particularly to a rotor structure for realizing cost reduction of this type of AC motor.

[Prior art]

In an AC motor, the armature winding is inserted into the winding groove of the stator core to form an annular cylindrical stator,
A synchronous permanent magnet motor is well known, in which a permanent magnet field rotor (rotor) having a permanent magnet for field formation inside the stator is rotatably provided along with the motor shaft, and the output torque performance is increased. Various improvements and innovations have been made for the purpose of reducing weight and size and maintaining output torque performance. In addition, the manufacturing and assembly costs of the motor are also reduced by saving materials and reducing the number of processing steps.

[Problems to be solved]

However, in recent years, industrial machinery, machine tools, etc.
With the advancement of complex technology that introduces microcomputers for motion control, the applications of electric motors, especially AC motors, have expanded, and therefore, in order to reduce machine costs, it has become necessary to reduce the manufacturing and assembly costs of serial motors. The demand for the latter is increasing. Therefore,
Regarding AC motors, there is an urgent need to realize low-cost AC motors by improving and devising materials selection, processing, and assembly methods while maintaining at least the output performance of the motor. Therefore, an object of the present invention is to focus on the structure of a permanent magnet field type rotor and to realize a low-cost structure as part of improvements and innovations regarding such AC motors.

[Means of solution and action]

That is, in view of the above-mentioned problems, the present invention provides a permanent magnet for an AC motor in which permanent magnet pieces corresponding to the number of poles are inserted into a yoke made of an electromagnetic steel plate and are sandwiched from the axial direction by a pair of end plate members. In the magnet field type rotor, each of the end plate members is constituted by a combination of a magnetically insulating flange plate made of a non-magnetic material that is closely attached to the end face of the yoke, and a fixed flange that fixes the rotor to the motor shaft. Provided is a permanent magnet field type rotor for an AC motor, and preferably the magnetic insulating flange plate is formed of a stainless steel stamping plate, and the fixed flange is formed of a cut structural carbon steel member, and the two are welded together. Alternatively, the above-mentioned combined body is constructed by joining by mechanical pressure welding.Inexpensive structural carbon steel is used and the two parts are joined by simple welding or mechanical pressure welding. Hereinafter, the present invention will be described in detail based on embodiments shown in the accompanying drawings.

〔Example〕

Fig. 1 is a sectional view of an AC motor having a permanent magnet field type rotor according to the present invention, Fig. 2 is a sectional view of the rotor portion of Fig. 1, and Fig. 3 is a structure and connection method of a flange assembly. FIG.

In FIGS. 1 and 2, an AC motor 8 includes a stator 10 having a stator core 16 fixed inside a stator housing 12 with an armature winding 14 in a winding groove, and a stator ID fixed to both ends of the stator core 16. end play)
A rotor 24 is fixed on a motor shaft 22 which is rotatably held by a rotary bearing 20.20 held at a rotary shaft 20. An excitation alternating current is supplied to the line 14 from the outside. The rotor 24 is formed as a permanent magnet field type rotor, and includes a yoke member 26 formed of a laminated core made of electromagnetic steel sheets, and permanent magnet pieces 28 for forming the field.
Two end plate members 30, 30, fixing bolts 32, etc. are provided,
A plurality of permanent magnet pieces 28 are inserted into the insertion groove of the yoke member 26 made of a laminated core according to the number of poles, and the yoke member 2
6 is a pair of end plate members 3 due to the fastening force of the fixing bolts 32.
It is sandwiched between 0.30 and 0.30. As shown in FIG. 2, motor output is generated on the motor shaft 22 by electromagnetic interaction between the magnetic flux generated by the permanent magnet pieces 28 and the armature winding 14 of the stator 10 to which alternating current is supplied. .

Now, here, the structure of each of the pair of end plate members 30, 30 in the permanent magnet field type rotor 24 of the AC motor of the present invention having the above-mentioned configuration is as shown in FIG.
4, a magnetic insulating flange plate 34 for insulating and preventing leakage of magnetic flux generated from the rotor 2, for example leakage to the motor shaft 22.
4 to the motor shaft 22, and the motor shaft 22 is fixed within the inner diameter hole 36a of the latter fixing flange 36 by appropriate fixing means such as a key fixing method. Therefore, a keyway may be provided in the inner diameter hole 36a at a position aligned with the motor shaft 22 in advance. Now, the magnetic insulating flange plate 34 is made of a non-magnetic material, most preferably a stainless steel material, and is formed, for example, by punching a stainless steel plate into a predetermined size and shape using a press machine.

On the other hand, the fixed flange 36 is mass-produced from an inexpensive mechanical structural steel bar by lathe processing or the like.

It goes without saying that the above-mentioned key grooves may be formed by a processing method using a slotter, broaching machine, or the like. In this case, steel for machine structures not only has a low material unit price but also has excellent workability, so the number of processing steps is small, thus contributing to cost reduction.

As described above, the magnetic insulating flange plate 34 and the fixed flange 36, which are each formed separately, are held together with a suitable jig and joined by welding at the corner 38, or mechanically pressure-welded. The bonding may be achieved by a method of. As shown in FIGS. 1 and 2, the end plate member 30 thus assembled is used to clamp the laminated core in the rotor 24 and fix the rotor 24 onto the motor shaft 22. It is something to be achieved.

〔Effect of the invention〕

According to the present invention, as is clear from the description of the embodiments above, the end plate members that are pressed against the ends of the laminated core of the permanent magnet field type rotor have magnetic insulation functions and fixation to the motor shaft. Each function is individually formed using appropriate and inexpensive materials, and a simple welding method or mechanical pressure welding method is used to join the two, contributing to cost reduction by reducing man-hours. In addition, it succeeded in reducing the cost of AC motors.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of an embodiment of an AC motor equipped with a permanent magnet field type rotor according to the present invention, and FIG. Figure 3 is a sectional view explaining the structure, processing, and assembly method of the end plate member. 8... AC motor, 10... Stator, 1
4... Armature winding, 24... Rotor, 26...
...Yoke, 28...Permanent magnet piece, 30
... End plate member, 34 ... Magnetic insulating flange plate, 36 ... Fixed flange, 38 ... Corner.

Claims (1)

[Scope of Claims] 1. A permanent magnet field type rotor for an AC motor, in which permanent magnet pieces corresponding to the number of poles are inserted into a yoke made of an electromagnetic steel plate and are sandwiched from the axial direction by a pair of end plate members. In the alternating current, each of the end plate members is constituted by a combination of a magnetically insulating flange plate made of a non-magnetic material that is in close contact with the end face of the yoke, and a fixed flange that fixes the rotor to the motor shaft. Permanent magnet field type rotor of motor. 2. The magnetic insulating flange plate is formed of a stainless steel punched plate, and the fixed flange is formed of a cut member of structural carbon steel, and both are formed into the combined body by welding. Permanent magnet field type rotor of the AC motor described. 3. The magnetic insulating flange plate is formed of a stainless steel punched plate, and the fixed flange is formed of a cut member of structural carbon steel, and both are formed into the combined body by mechanical pressure welding. Permanent magnet field type rotor of the AC motor described in 2.