JPH0614505A - Rotor of electric motor - Google Patents

Abstract

PURPOSE:To provide a rotor wherein it restrains that a coolant and a refrigerator-oil mixed liquid are stirred by the weight of the rotor when the shaft of a compressor is installed transversely, it reduces the load of an electric motor and it can reduce a sound by a stirring operation in the rotor of the electric motor, for compressor use, which is provided with a permanent magnet. CONSTITUTION:Degassing holes 7 whose number is eual to that of balance- correcting holes 6 and whose area is smaller that of the balance-correcting holes 6 are made in a flat boardlike nonmagnetic end plate 4. The central position of each degassing hole 7 in the flat boardlike nonmagnetic end plate is set on the extension line between the center of each balance-correcting hole 6 and the axial center of a rotor laminated core 1. Each balance-correcting hole 6 and each hole 7 in the flat boardlike nonmagnetic end plate are brought into internal contact with each other in a position which is most distant from the axial center of the rotor laminated iorn core 1. Thereby, it is possible to realize the rotor, of an electric motor for compressor use, in which the load of the electric motor is small and in which a sound by a stirring operation is small.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotor of an electric motor having an iron core for forming a magnetic path in a portion close to an inner diameter and having a permanent magnet on the outer side thereof.

[0002]

2. Description of the Related Art A rotor of an electric motor used for a compressor for an air conditioner is provided with a component different from a rotor iron plate as disclosed in JP-A-2-246748 in order to correct an unbalance amount of load. A structured external weight is generally used and is attached to one side or one side of the rotor end face. FIG. 2 shows an example of a rotor of a compressor electric motor having an iron core for forming a magnetic path in a portion close to the inner diameter and having a permanent magnet on the outer side thereof. The external weight 8 is a clamp pin 5
Is attached to the flat non-magnetic end plate 4.

However, if the rotary shaft of the compressor is installed horizontally, the mixed liquid of the refrigerant and the refrigerating machine oil in the compressor will immerse a part of the rotor. At this time, if the external weight 8 as shown in FIG. 2 is attached to the rotor,
When the compressor is in operation, the radial end surface of the weight 8 strikes the liquid surface of the mixed liquid by the rotation of the rotor and stirs the liquid surface. It becomes a problem. As a measure against the above-mentioned problem, R is attached to the end face in the radial direction of the external weight.
Although there is a method of lowering the resistance when the liquid surface of the mixed solution is hit with a liquid, it does not solve the problem that the external weight is repeatedly dipped in the mixed solution. As another countermeasure, there is a method in which a donut-shaped cover is further attached to the outside of the external weight to completely cover the external weight, but this increases the number of parts and the mounting process, which increases the cost.

[0004]

In order to solve the above problem, there is a method of eliminating the external weight 8 and providing a balance correction hole in the rotor laminated core instead. However, a flat non-magnetic end plate is provided on the axial end surface of the rotor of the compressor electric motor having a permanent magnet in order to prevent falling powder due to chipping of the magnet. If the balance correction hole is completely covered with the flat non-magnetic end plate, the mixture liquid of the refrigerant and the refrigerating machine oil that has entered the balance correction hole through the gap between the laminated iron plates when the compressor is stopped will operate the compressor. When the temperature starts, the temperature rises and the flat non-magnetic end plate is deformed in an attempt to vaporize rapidly. Further, the refrigerating machine oil having a high viscosity is difficult to be discharged immediately from a small gap between the laminated iron plates even by the centrifugal force due to the rotation of the rotor, which causes the rotor to lose its balance.

On the other hand, if a hole for degassing of the same area is provided at the same position as the balance correction hole in the flat non-magnetic end plate, a part of the rotor is immersed in the liquid mixture of the refrigerant and the refrigerating machine oil. , Each time the balance correction hole provided on the end face of the rotor is immersed in the mixed solution by the rotation of the rotor, the mixed solution goes in and out of the balance correction hole to increase the load on the motor, and further Sound is generated by stirring the liquid.

In view of the above problems, it is an object of the present invention to provide a rotor for a compressor electric motor having a permanent magnet capable of improving the compressor performance.

[0007]

In order to achieve the above object, the present invention provides a rotor iron plate in which a balance correction hole for absorbing an unbalance amount of a load is punched out, and a rotor not provided with the balance correction hole. A plurality of arcuate magnets are fixed on the outer circumference of a rotor laminated core in which iron plates are laminated, and flat non-magnetic end plates are provided on both axial end faces of the rotor laminated iron core. A rotor in which a plate and the rotor laminated iron core are integrally clamped in the axial direction through clamp pins, the number of which is the same as the balance correction holes in the flat plate-shaped non-magnetic end plate, and smaller than the area of the balance correction holes. A vent hole for discharging refrigerant and refrigerating machine oil is provided, and the center position of the vent hole of the flat non-magnetic end plate is on the extension line between the center of the balance correction hole and the axial center of the rotor laminated core. And Serial is a balance correction holes that the and the gas vent hole of the plate on the non-magnetic end plate was be inscribed at the farthest position from the axial center of the rotor laminated core.

[0008]

According to the present invention, even if the rotary shaft of the compressor is horizontally installed and a part of the rotor is immersed in the mixed liquid of the refrigerant and the refrigerating machine oil, the flat non-magnetic end plate is degassed by the above structure. Since a hole for use is provided, even if the temperature of the refrigerant liquid in the mixed liquid that has entered the balance correction hole when the compressor is stopped rises rapidly when the compressor starts, this gas will not The flat nonmagnetic end plate is not deformed because it is easily discharged from the gas vent hole of the flat nonmagnetic end plate to the outside of the balance correction hole. Moreover, since the area of the gas vent hole provided in the flat non-magnetic end plate is smaller than the area of the balance correction hole, the balance correction hole is immersed in the mixed liquid by the rotation of the rotor. The amount of the mixed solution flowing in and out of the balance correction hole is smaller than that in the case where the area of the gas vent hole provided in the flat non-magnetic end plate is the same as the area of the balance correction hole. Further, the gas release hole of the flat plate-shaped non-magnetic end plate and the balance correction hole are inscribed at a position farthest from the axial center of the rotor laminated iron core, so that the flat plate-shaped non-magnetic end plate and the balance correction hole are Since there is no step between them, the mixed liquid that has entered the balance correction hole when the compressor is stopped is not only the refrigerant liquid due to the centrifugal force due to the rotation of the rotor but also the refrigerating machine oil with high viscosity. However, the structure is such that the rotor is discharged without resistance to the balance correction hole, and the balance of the rotor is not lost. With the above operation, stirring of the mixed liquid due to the balance correction hole of the rotor is reduced, and the load on the electric motor is small and the noise due to stirring can be reduced.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a rotor of a compressor motor having a permanent magnet according to the present invention will be described below with reference to the drawings.

FIG. 1A is a view showing the positional relationship between a balance correction hole and a flat plate-shaped non-magnetic end plate according to an embodiment of the present invention as seen from the rotor end face, and FIG. 1B is a view of A- of the rotor. FIG. 1 is a rotor laminated iron plate iron core, 2 is an arcuate magnet, 3 is a non-magnetic metal pipe, 4 is a flat plate-shaped non-magnetic end plate, 5 is a clamp pin, 6 is a balance correction hole, and 7 is a flat plate-shaped non-magnetic end plate. The provided vent hole 8 is an externally attached weight.

A plurality of rotor iron plates are formed on the outer circumference of a rotor laminated core 1 in which a rotor iron plate punched with a balance correction hole 6 for absorbing an unbalance amount of load is punched and a rotor iron plate not provided with the balance correction hole 6 are laminated. It has an arcuate magnet 2, and a non-magnetic metal pipe 3 is shrink-fitted or press-fitted on the outer circumference of the plurality of arcuate magnets 2 to prevent falling powder due to chipping of the magnets. The flat non-magnetic end plates 4 are provided on both end faces in the direction, and the flat non-magnetic end plates 4 and the rotor laminated core 1
Is a rotor in which the clamp pin is integrally clamped in the axial direction through a clamp pin.
The number of gas vent holes 7 is the same as that of the balance correction hole 6 and is smaller than the area of the balance correction hole 6, and the center position of the gas release hole 7 of the flat non-magnetic end plate is set to the center of the balance correction hole 6 and the rotor laminated core 1. The balance correction hole 6 and the degassing hole 7 of the non-magnetic end plate on the flat plate are on the extension line of the shaft center, and the rotor laminated core 1
Be inscribed at the furthest position from the axis center of.

With the above structure, the flat non-magnetic end plate 4 does not completely cover the balance correction hole 6, so that the refrigerant and the refrigerating machine oil are mixed when the compressor with the rotary shaft placed sideways is stopped. When the liquid is stored in the balance correction hole 6 and the refrigerant is rapidly vaporized due to the temperature rise accompanying the start of operation of the compressor, the gas is not trapped and the flat non-magnetic end plate 4 is deformed. I can't reach it. Further, since the area of the degassing hole 7 of the flat non-magnetic end plate is smaller than the area of the balance correction hole 6, the balance correction hole 6 is immersed in the mixed liquid of the refrigerant and the refrigerating machine oil by the rotation of the rotor. In addition, the amount of the mixed solution flowing in and out of the balance correction hole 6 is smaller than that of the balance correction hole 6 in the area of the gas vent hole 7 of the flat non-magnetic end plate. On the other hand, the area of the gas vent hole 7 provided in the flat non-magnetic end plate is smaller than the area of the balance correction hole 6, and the center of the gas vent hole 7 and the center of the balance correction hole 6 provided in the flat non-magnetic end plate. If they match, a step will be formed between the balance correction hole 6 and the gas vent hole 7 provided in the flat non-magnetic end plate, so that centrifugal force due to rotation of the rotor during operation may also occur. The mixed liquid of the refrigerant and the refrigerating machine oil is stored between the step and is not completely discharged from the balance correction hole 6. Therefore, the center position of the gas vent hole 7 provided in the flat non-magnetic end plate 4 should be on the extension line between the center of the balance correction hole 6 and the axial center of the rotor laminated core 1, and the balance correction hole 6 and the flat plate Between the balance correction hole 6 and the gas vent hole 7 provided in the flat non-magnetic end plate by inscribing the gas vent hole 7 of the non-magnetic end plate at the position farthest from the axial center of the rotor laminated iron core 1. Since there is no level difference in the structure, during operation, not only the refrigerant but also the refrigerating machine oil with high viscosity are easily discharged from the balance correction hole 6 by the centrifugal force due to the rotation of the rotor.

[0013]

As described above, the following effects can be obtained by the present invention. 1. Effect on Characteristics of Motor for Compressor (a) Even if the rotary shaft of the compressor is installed horizontally and a part of the rotor is immersed in the mixed liquid of the refrigerant and the refrigerating machine oil, the flat non-magnetic end plate 4 Since there is a hole 7 for degassing,
Even if the refrigerant liquid in the mixed liquid that has entered the balance correction hole 6 when the compressor is stopped is rapidly vaporized due to the temperature rise when the compressor is started, this gas is released from the flat non-magnetic end plate. Since it is easily discharged from the hole 7 to the outside of the balance correction hole 6, the flat non-magnetic end plate 4 is not deformed, component accuracy is maintained, and the characteristics of the compressor motor are not changed. (B) Since the area of the gas vent hole 7 provided in the flat non-magnetic end plate is smaller than the area of the balance correction hole 6, each time the balance correction hole 6 is immersed in the mixed liquid by the rotation of the rotor,
The amount of the mixed solution entering and leaving the balance correction hole 6 is
Since the area of the gas vent hole 7 provided in the flat non-magnetic end plate is smaller than that of the case where the area of the balance correction hole 6 is the same, the stirring of the mixed liquid caused by the balance correction hole 6 of the rotor is small. Since the load on the electric motor can be reduced and the noise caused by stirring can be reduced, an efficient and quiet compressor can be realized. (C) The gas vent hole 7 of the flat plate-shaped non-magnetic end plate and the balance correction hole 6 are inscribed at the position farthest from the axial center of the rotor laminated iron core to form the gas vent hole 7 of the flat plate-shaped non-magnetic end plate. Since there is no step between the balance correction holes 6, the mixed liquid that has entered the balance correction holes 6 when the compressor is stopped is not only the refrigerant liquid but also the viscosity due to the centrifugal force due to the rotation of the rotor when the compressor is operating. Even a high refrigerating machine oil is discharged to the outside of the balance correction hole 6 without resistance, so that a compressor with less vibration without losing the balance of the rotor can be realized. 2. Effect on manufacturing of electric motor for compressor Since the doughnut-shaped cover attached to the outside of the external weight 8 required when the external weight 8 is provided is not necessary, the number of parts is reduced, the cost is reduced, and the process is also simplified. Therefore, automation becomes possible, which has a great effect on the manufacture of the compressor electric motor.

[Brief description of drawings]

FIG. 1A shows the positional relationship between a balance correction hole of a rotor of a compressor motor having a permanent magnet according to an embodiment of the present invention and a gas vent hole provided in a flat non-magnetic end plate of the rotor. The figure seen from the end surface (b) is an AA vertical sectional view of the rotor shown in FIG. 1 (a).

FIG. 2 is a cross-sectional view of a conventional rotor in which an external weight is attached to the rotor of a compressor electric motor having a permanent magnet.

[Explanation of symbols]

 1 rotor laminated iron plate iron core 2 arcuate magnet 3 non-magnetic metal pipe 4 flat plate non-magnetic end plate 5 clamp pin 6 balance correction hole 7 gas vent hole provided in flat plate non-magnetic end plate 8 external weight

Claims (1)

[Claims] 1. A plurality of rotor iron cores, each of which is formed by laminating a rotor iron plate having punched balance correction holes for absorbing an unbalance amount of a load and a rotor iron plate having no unbalance correction holes, on the outer periphery of the rotor laminated iron core. Fixing a bow-shaped magnet, and providing flat non-magnetic end plates on both axial end faces of the rotor laminated core, and passing the flat non-magnetic end plate and the rotor laminated iron core through clamp pins in the axial direction. The integrally clamped rotor, the flat plate-shaped non-magnetic end plate is provided with holes equal in number to the balance correction holes and smaller than the area of the balance correction holes, and The center position is on an extension line between the center of the balance correction hole and the axial center of the rotor laminated core, and the balance correction hole and the hole of the flat non-magnetic end plate are the axial centers of the rotor laminated core. Farthest from The rotor of the motor, characterized in that the contact.