JP4043665B2 - Self-starting permanent magnet synchronous motor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a self-starting permanent magnet type synchronous motor used for electric compressors for refrigeration and refrigeration equipment and air-conditioning equipment and general industries .
[0002]
[Prior art]
The self-starting permanent magnet type synchronous motor operates as an induction motor by a squirrel-cage-shaped conductor for starting the rotor at the time of starting. The synchronous operation is carried out by being drawn into the rotating magnetic field rotating around, but has excellent performance such as constant speed operation and high efficiency. In particular, various improvements have been made to the rotor structure of an electric motor.
[0003]
An example of a conventional rotor of a self-starting permanent magnet type synchronous motor is disclosed in Japanese Patent Publication No. 63-20105. Hereinafter, the rotor of the conventional self-starting permanent magnet type synchronous motor will be described with reference to FIGS.
[0004]
FIG. 14 is an axial sectional view of the rotor of the self-starting permanent magnet synchronous motor, and FIG. 15 is a radial sectional view taken along line AA ′ of FIG. 14 and 15, 1 is a rotor, and 2 is a rotor core made of laminated electromagnetic steel sheets. Reference numeral 3 denotes a conductor bar, and both ends thereof are connected to the short-circuit ring 4 to form a starting cage conductor. Reference numeral 5 denotes a permanent magnet which is embedded in the rotor core to form a 4-pole rotor magnetic pole. Reference numeral 6 denotes a magnetic flux short-circuit preventing slit for preventing a magnetic flux short-circuit between adjacent permanent magnets of different polarities. Reference numeral 7 denotes an end plate, which is disposed on both end faces of the rotor core in the axial direction and is fixed to the rotor core 2 with 8 bolts to prevent the permanent magnet 5 from falling off. Reference numeral 9 denotes a shaft on which the rotor 1 is mounted.
[0005]
[Problems to be solved by the invention]
However, the above-described conventional configuration has a configuration in which the end plate is attached to the rotor core using a plurality of bolts, so that there is a problem that the material cost and assembly man-hours are increased, and the cost of the electric motor is increased. .
[0006]
The present invention solves the conventional problems, and provides an inexpensive self-starting permanent magnet synchronous motor that can be assembled easily by attaching an end plate without using bolts, and can be easily assembled. With the goal.
[0007]
The projections of the start cage conductor and the end plate for securing the dynamic co-molded with aluminum die cast, after fitting the fitting Goana end plate to the projecting portion, rotating the end plate the tip of the protrusion presses enlarged than those fixed to the end face of the child core, it can be attached easily end plate without using bolts, material cost is and the assembly can be performed easily.
[0008]
In addition , in a configuration in which a part or the whole of the end plate disposed on one end surface in the axial direction of the rotor core is covered with a short-circuit ring, the tip of the projection for fixing the end plate is pressed and enlarged. Thus, the work for attaching the end plate to the end face of the rotor core is only required on one side, and the assembly can be further simplified.
[0009]
Further , a part or the whole of the end plate disposed on one end face in the axial direction of the rotor core is covered with a short-circuit ring, and the protrusion provided on the end plate is fitted into the hole A of the rotor core. With such a configuration , the end plate can be easily positioned, and the end plate is not displaced with respect to the flow of high-pressure aluminum during aluminum die casting.
[0010]
Moreover, the electrical steel sheet B of one of the axial ends of the rotor core obtained by the structure without the holes for the permanent magnets buried, the end plate is not required and will end plate of the side requires only one other side Therefore, material costs and assembly man-hours can be greatly reduced.
[0011]
Further , in the case where a projection is provided at a location where the electromagnetic steel plate B comes into contact with the permanent magnet , the permanent magnet comes into contact with only the projection of the electromagnetic steel plate and is positioned in the axial direction. The magnetic flux short circuit through the electromagnetic steel plate B between the different polarities can be greatly reduced, and the performance of the electric motor can be improved.
[0012]
[Means for Solving the Problems]
The present invention is configured to fit a convex portion provided on the outer periphery of the end plate and a concave portion provided on the inner periphery of the short-circuit ring, and by pressing and deforming the periphery of the concave portion of the short-circuit ring in the axial direction, The plate is fixed to the end face of the rotor core, and this allows the end plate to be easily attached.
[0013]
Furthermore, in the present invention, the permanent magnet is formed of a rare earth magnet, and a strong magnetic force is obtained by this, so that the rotor and the entire motor can be reduced in size and weight.
[0014]
Note that a stator in which a winding is wound around a stator core, a plurality of conductor bars that rotate freely facing an inner cylindrical surface of the stator core, and that are positioned near the outer periphery of the rotor core and the rotation A short-circuit ring located on both end faces in the axial direction of the child is integrally formed by aluminum die casting to form a starting cage conductor, and a rotor in which a plurality of permanent magnets are embedded inside the conductor bar. An axial hole A is provided inside the permanent magnet embedding hole of the rotor iron core, the hole A is filled with aluminum die casting simultaneously with the starting cage conductor, and the rotation of the hole A is performed. An end plate fixing projection that protrudes in the axial direction from the end surface of the core is formed, and a fitting hole of an end plate made of a nonmagnetic material is fitted into the projection, and then the tip of the projection is pressed and enlarged. The end plate was fixed to both end faces of the rotor core by Since, Ru can be attached to and easily end plate with an inexpensive material by this.
[0015]
In addition, in the case where a part or the whole of the end plate disposed on one end surface in the axial direction of the rotor core is covered with a short-circuit ring, this expands the tip of the projection for fixing the end plate. operation of fixing the end face of the rotor core end plates Te is since it is only on one side, Ru can be reduced assembling steps.
[0016]
Furthermore, if the end plate on the side covered with the short-circuit ring is provided with a protrusion that fits into the hole A of the rotor core, the positioning of the end plate can be easily and accurately fixed. The
[0017]
Note that a stator in which a winding is wound around a stator core, a plurality of conductor bars that rotate freely facing an inner cylindrical surface of the stator core, and that are positioned near the outer periphery of the rotor core and the rotation A short-circuit ring located on both end faces in the axial direction of the child is integrally formed by aluminum die casting to form a starting cage conductor, and a rotor in which a plurality of permanent magnets are embedded inside the conductor bar. One or a plurality of electromagnetic steel plates B at one axial end of the rotor core is not provided with a permanent magnet embedding hole, and for permanent magnet embedding of the rotor core. An axial hole A is provided inside the hole, the hole A is filled with aluminum die casting at the same time as the starting cage conductor, and the axial direction from the end surface of the rotor core opposite to the electromagnetic steel plate B of the rotor core A protrusion for fixing the end plate is formed on the protrusion. After fitting the fitting Goana end plate made of a nonmagnetic material in part, by pressing expand the tip of the protrusion, the end plate which was fixed to the end face of the rotor core, by this end plates Ru can be greatly reduced material costs and assembly man-hours so requires only one.
[0018]
In addition, in the case where a protrusion projecting toward the permanent magnet is provided at a position where the magnetic steel sheet B comes into contact with the permanent magnet , the permanent magnet is contacted only with the magnetic steel sheet protrusion and is positioned in the axial direction. next, the magnetic flux short circuit through the electromagnetic steel B between different poles of the sides of the permanent magnets can be significantly reduced, Ru can improve the performance of the motor.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
The present invention includes a stator in which a winding is wound around a stator core, a plurality of conductor bars that are freely rotated to face the inner cylindrical surface of the stator core, and are located near the outer periphery of the rotor core; A rotor with a short-circuit ring positioned on both end faces in the axial direction of the rotor is integrally formed by aluminum die casting to form a starting cage conductor, and a plurality of permanent magnets are embedded inside the conductor bar; those consisting of odor Te, provided with a convex portion on the outer periphery of the end plate of non-magnetic material, fitted to the end plate projecting portion of the end plate is provided with a recess to fit the inner periphery of the short circuit ring Then, the end plate is fixed to the end surface of the rotor core by pressing and deforming the periphery of the concave portion of the short-circuit ring in the axial direction. This allows the end plate to be easily attached and reduces the number of assembly steps. It has the effect of being able to.
[0020]
In the above, than that of the permanent magnet is formed by a rare earth magnet, the strong magnetic force is obtained by this, the entire rotor or motor Ru can be made smaller and lighter.
[0021]
【Example】
Embodiments of a self-starting permanent magnet synchronous motor according to the present invention will be described below with reference to the drawings. Reference examples will also be described. About the same structure as the past, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted. Further, since the stator has the same configuration as a general self-starting permanent magnet synchronous motor, description of the stator is also omitted.
[0022]
( Reference Example 1)
This will be described with reference to FIGS. Figure 1 is an axial cross-sectional view of a rotor of a self-starting permanent magnet synchronous motor according to Reference Example 1 of the present invention, FIG. 2 is a radial sectional view of FIG. FIG. 3 is a plan view of the end plate. 1 and 2, 1 is a rotor, and 2 is a rotor core made of laminated electromagnetic steel sheets. Reference numeral 3 denotes a conductor bar, which is integrally formed with a short-circuit ring 4 positioned at both ends in the axial direction of the rotor core 2 and an aluminum die cast to form a starting cage conductor. Reference numeral 5 denotes a permanent magnet, in which two flat permanent magnets 5 having the same polarity are arranged so as to face each other in a mountain shape to form a one-pole rotor magnetic pole, and the entire rotor is a two-pole rotor. A magnetic pole is formed. Reference numeral 7 denotes a magnetic flux short-circuit prevention barrier for preventing a magnetic flux short-circuit between adjacent permanent magnets of different polarities, which is also filled with aluminum die casting. Reference numeral 8 denotes an end plate made of a nonmagnetic material for protecting the permanent magnet 5, and is provided with a fitting hole 8a. Reference numeral 9 denotes a hole A provided in the axial direction of the rotor core 2. The hole A is filled with aluminum 10 which is simultaneously formed by a squirrel-cage conductor and aluminum die casting, and the aluminum 10 is the rotor core 2. Projecting portions 10a are formed so as to protrude in the axial direction from both axial end surfaces of the. After the end plate 8 is fitted with the fitting hole 8a to the protruding portion 10a, the end plate 8 is pressed and enlarged as indicated by a broken line to fix the end plate 8 to the end surface of the rotor core 2.
[0023]
As described above, in the self-starting permanent magnet type synchronous motor of this reference example , the protrusion 10a for fixing the end plate 8 of the rotor 1 is integrally formed with the starting squirrel-cage conductor and the aluminum die-cast, and the protrusion Since the end plate 8 is fixed to the end face of the rotor core 2 simply by pressing and enlarging the tip of 10a, the material cost is lower than the bolt fixing as in the conventional example, and the number of assembly steps can be greatly reduced. An inexpensive self-starting permanent magnet type synchronous motor can be provided.
[0024]
( Reference Example 2)
This will be described with reference to FIGS. Figure 4 is an axial sectional view of a rotor of a self-starting permanent magnet synchronous motor in Reference Example 2 of the present invention. 5 is a plan view of the end plate 12 in FIG. 4, and FIG. 6 is a cross-sectional view taken along the line CC ′ of FIG. In FIG. 4, the short ring 4 a is formed so as to cover the end plate 12. As a result, the end plate 12 is integrally fixed to the end face of the rotor core 2 by aluminum die casting forming a starting cage conductor. 5 and 6, the end plate 12 is provided with two projections 12a, and the projection 12a is provided with a hole 12b at the center. The end plate 12 is formed by press-fitting and fixing the projection 12a of the end plate 12 in the hole A9 at the end of the rotor core 2 before die casting the aluminum, and the end plate 12 is positioned and die-cast at a high pressure. Even if the aluminum flows, the position of the end plate 12 is not displaced and is accurately fixed to the end face of the rotor core 2. Further, even when aluminum is caused to flow from the end plate 8 side during aluminum die casting, the aluminum smoothly flows to the short-circuiting ring 4a by the holes 12b provided in the protruding portion 12a of the end plate 12. On the other hand, after the end plate 8 is fitted into the end plate fixing projection 10a as in the case of the above-described Reference Example 1, the tip end of the projection 10a is pressed and enlarged as indicated by a broken line, and the rotor core 2 is Fixed to the end face.
[0025]
As described above, since the end plate 12 is integrally fixed to the rotor core 2 by aluminum die casting in the self-starting permanent magnet synchronous motor of this reference example , the end plate is fixed by pressing and expanding the protruding portion 10a. Only one end plate 8 is required for the work, and the number of assembling steps can be further reduced as compared with the case of the reference example 1 described above.
[0026]
( Reference example 3) It demonstrates using FIG. 7 and FIG. Figure 7 is an axial sectional view of a rotor of a self-starting permanent magnet synchronous motor according to the third embodiment of the present invention. FIG. 8 is a plan view of the electrical steel sheet located at the axial end of the rotor core in FIG. 7 and 8, the electromagnetic steel sheet 20 located at the axial end of the rotor core 2 has the same shape as the electromagnetic steel sheets at other positions and the slot 21 for the conductor bar at the same position, the barrier hole for preventing magnetic flux short-circuiting. 22, the hole A9 and the shaft hole 10 are provided, but the permanent magnet embedding hole 6 is not provided. The electromagnetic steel sheet 20 is punched with the same core mold as the other electromagnetic steel sheets, but the tooth mold for punching the permanent magnet embedding hole 6 at that time can be freely inserted and removed from the mold body. It is easy to prevent the permanent magnet embedding hole 6 from being formed when the electromagnetic steel sheet 20 is punched. Therefore, the rotor core 2 including the electromagnetic steel plate 20 can be easily formed integrally, and a starting cage conductor can be formed by aluminum die casting.
[0027]
Since the rotor is configured as described above, one end plate is not required, and the operation of pressing and expanding the protruding portion 10a to fix the end plate is the same as that of the reference example 2 with only one end plate 8. As a result, material costs and assembly man-hours can be further reduced.
[0028]
( Reference Example 4)
This will be described with reference to FIGS. 9 and 10. FIG. 9 is a plan view of the electromagnetic steel plate at the axial end of the rotor core, and FIG. 10 is an enlarged partial vertical cross-sectional view of the rotor 1.
[0029]
9 and 10, reference numeral 23 denotes an electromagnetic steel plate disposed at the axial end of the rotor core 1, and reference numeral 24 denotes a portion where the permanent magnet 5 of the electromagnetic steel plate 23 comes into contact with the permanent magnet 5. It is a protruding part. Therefore, the permanent magnet 5 comes into contact with only the protrusion 24 of the electromagnetic steel plate 23 and is positioned in the axial direction.
[0030]
Thereby, the magnetic flux short circuit through the electromagnetic steel plate 23 between the opposite poles of the front and back of the permanent magnet 5 can be significantly reduced, and the performance of the electric motor can be improved. The electromagnetic steel sheet 23 is punched with the same core mold as the other electromagnetic steel sheets. At this time, the tooth mold for forming the projection 24 can be freely inserted and removed from the mold body, so that the rotor core is formed. 2 can be easily formed integrally including the electromagnetic steel plate 23.
[0031]
(Example 1 )
This will be described with reference to FIGS. FIG. 11 is a sectional view in the axial direction when the rotor of the self-starting permanent magnet synchronous motor according to the first embodiment is completed. FIG. 12 is a sectional view in the axial direction before fixing the end plate of the rotor, and FIG. 13 is a side view of FIG. 12 and 13, the end plate 31 is provided with a convex portion 31 a on the outer periphery, and a concave portion 30 a that fits the convex portion 31 a of the end plate 31 is provided on the inner periphery of the short-circuit ring 30 formed by aluminum die casting. is there. After the convex portion 31a of the end plate 31 is fitted into the concave portion 30a of the short-circuit ring 30, the periphery of the concave portion 30a of the short-circuit ring 30 is pressed in the axial direction so as to be deformed as 30b in FIG. It is fixed to the core 2.
[0032]
According to the configuration as described above, the end plate 31 can be fixed simply by pressing and deforming the recess 30a of the short-circuit ring 30, so that the number of assembling steps can be reduced.
[0033]
( Reference Example 5 )
Although not shown, if the permanent magnet is formed of a rare earth magnet such as neodymium / iron / boron, a strong magnetic force can be obtained, so that the rotor and the entire motor can be reduced in size and weight.
[0034]
In addition , although the example of 2 poles was used in the Example, it is not restricted to this, For example, it is the same also about the rotor which forms other magnetic pole numbers, such as 4 poles.
[0035]
Further , in the embodiment, two flat permanent magnets having the same polarity are abutted in a mountain shape to constitute one pole, but the present invention is not limited to this. A single pole may be configured by abutting polar permanent magnets, and the same measures should be taken for rotors that have one pole using one or more permanent magnets in other shapes such as arcs. Can do.
[0036]
【The invention's effect】
As described above, the present invention includes a stator in which a winding is wound around a stator core, and a plurality of rotors that rotate freely facing the inner cylindrical surface of the stator core and are located near the outer periphery of the rotor core. The conductor bar and the short-circuit ring positioned on both end faces in the axial direction of the rotor are integrally molded by aluminum die casting to form a starting cage conductor, and a plurality of permanent magnets are embedded inside the conductor bar the Te odor made of a rotor, provided with a convex portion on the outer periphery of the end plate of non-magnetic material, the convex portion of the end plate is provided with a recess to fit the inner periphery of the short circuit ring, After the end plate is fitted, the periphery of the concave portion of the short-circuit ring is pressed and deformed in the axial direction, and the end plate is fixed to the end surface of the rotor core, which makes it easy to attach the end plate. Self-starting that can reduce assembly man-hours and is inexpensive Ru can provide a permanent magnet synchronous motor.
[Brief description of the drawings]
Figure 1 is a plan view of the axial cross-sectional view of the self-starting permanent magnet synchronous motor [2] the same radial cross-sectional view [FIG 3] the end plate of Example 1 [FIG. 4] self-starting of Reference Example 2 C-C 'cross section of a plan view of an axial cross-sectional view of the shape permanent magnet synchronous motor [5] the end plate 6 the end plates 7 self-starting permanent magnet synchronous reference example 3 Sectional view of the motor in the axial direction [Fig. 8] Plan view of the electromagnetic steel plate at the end of the rotor core [Fig. 9] Plan view of the electromagnetic steel plate at the end of the rotor core in Reference Example [Fig. Partial vertical cross-sectional enlarged view [FIG. 11] Axial cross-sectional view of the self-starting permanent magnet type synchronous motor of Example 1 according to the present invention [FIG. 12] Axial cross-sectional view before fixing the end plate [FIG. Side view [Fig. 14] Axial sectional view of a conventional self-starting permanent magnet synchronous motor [Fig. 15] Same-diameter sectional view [Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Rotor 2 Rotor core 3 Conductor bar 4, 30 Short ring 5 Permanent magnet 6 Permanent magnet embedding hole 8, 12, 31 End plate 9 Hole A
10a Aluminum projection 12a End plate projection 20 Electrical steel plate B
24 Protrusion part of electromagnetic steel plate B 30a Concave part of inner periphery of short-circuit ring 31a Convex part of outer periphery of end plate

Claims (1)

A stator in which windings are wound around a stator core, a plurality of conductor bars that rotate freely facing an inner cylindrical surface of the stator core, and that are positioned near the outer periphery of the rotor core; and a short-circuit ring is positioned on both end faces in the axial direction to form the integrally molded to the starter cage conductor in aluminum die-casting, odor made of a rotor embedded a plurality of permanent magnets inside the conductor bars And providing a convex portion on the outer periphery of the end plate made of a non-magnetic material, and providing a concave portion such that the convex portion of the end plate is fitted on the inner periphery of the short-circuit ring, and fitting the end plate, A self-starting permanent magnet type synchronous motor characterized in that the end plate is fixed to the end face of a rotor core by pressing and deforming the periphery of the recess of the short-circuit ring in the axial direction.

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