JP3306343B2 - Motor rotor - Google Patents

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 an electric motor used for a compressor or the like.

[0002]

2. Description of the Related Art Conventionally, a rotor of a compressor motor of this kind, particularly a rotor of a motor called a brushless DC motor,
For example, it is configured as shown in FIG. 4 (C) of Japanese Patent Application No. 5-138893 filed earlier by the applicant. That is,
In the conventional rotor, a plurality of iron plates for a rotor are laminated and fixed by caulking to form a rotor core, and four (in the case of four poles) magnetic poles are formed along the outer peripheral side of the rotor core. A magnetic material (permanent magnet) is inserted, and the outer peripheral surface of the rotor core is formed with a notch between the magnetic materials to form a salient pole portion, thereby preventing a short circuit of magnetic flux.

Further, a through-hole for caulking and fixing upper and lower non-magnetic end face members and the like is formed in the rotor iron plate of the rotor core, and the end face member and the oil separating oil are separated by using rivets in the through holes. Was fixed to the rotor core by caulking.

On the other hand, as shown in FIG. 4 and disclosed in JP-A-47-27302, a plurality of flat permanent magnets 100 are provided.
With the rotor 101 such that their magnetic paths are tangential.
Are radially inserted and arranged from the center.

[0005]

However, in the former rotor, since the through hole is formed inside the notch, that is, between the magnetic bodies, when the number of magnetic poles is four or more,
A through hole exists in a magnetic path formed between adjacent magnetic bodies (magnetic poles). For this reason, there has been a problem that the magnetic resistance increases in the through hole and the output of the motor decreases.

In the latter configuration, four insertion holes 1 are provided.
02, four magnets 100 are inserted into the outer periphery of the magnet 100.
It is necessary to provide a protrusion preventing member 103 for preventing 00 from popping out due to centrifugal force, which increases the number of parts and complicates the operation. In addition, since there are four magnets, there is a problem that the magnetic force is limited and desired characteristics cannot be obtained.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional technical problem, and not only reduces the adverse effect due to the through-hole for caulking but also reduces the number of parts and facilitates the assembly work. It is an object of the present invention to provide a rotor of an electric motor having characteristics.

[0008]

According to the present invention, there is provided a rotor core in which a plurality of rotor iron plates are laminated.
And the rotor core is provided along the axial direction of the rotating shaft
And four insertion holes inserted into these holes.
The plate-shaped permanent magnet and the outer peripheral surface of the rotor core are
Excision to form a narrow first bridge between the insertion hole
Are provided at four locations, and one end of the insertion hole has the first bridge.
The other end is sandwiched by the narrow second bridge
And shaped like a girder facing the side of the adjacent insertion hole.
In the rotor of the electric motor formed, the rotor core
End member for closing the insertion holes provided on both end surfaces of the
Multiple piercings that penetrate the member and rotor core along the rotation axis direction
A through hole, and the end face member and the rotating member using the through hole.
A rivet integrally formed with a child core, wherein the through-hole is
Concentrically provided inside the insertion hole, the center of each magnetic pole
In each of the magnetic poles outside the through hole,
Oval air holes that are inclined
You.

[0009]

[0010]

[0011]

[0012]

[0013]

[0014]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a vertical sectional side view of a compressor C to which a rotor of an electric motor according to the present invention is applied. In this figure, reference numeral 1 denotes a closed container, and an electric motor (brushless DC)
A motor (2) and a compression element (3) rotatably driven by the electric motor (2) are housed below. The airtight container 1 is obtained by storing the electric motor 2 and the compression element 3 in a preliminarily divided into two parts and then sealing them by high frequency welding or the like.

The electric motor 2 comprises a stator 4 fixed to the inner wall of the closed casing 1 and a rotor 5 supported inside the stator 4 so as to be rotatable around a rotating shaft 6. . The stator 4 includes a stator winding 7 that applies a rotating magnetic field to the rotor 5.

The compression element 3 includes a first rotary cylinder 9 and a second rotary cylinder 10 separated by an intermediate partition plate 8. Eccentric portions 11 and 12 that are driven to rotate by the rotating shaft 6 are attached to the cylinders 9 and 10, respectively. The eccentric portions 11 and 12 are 180 degrees out of phase with each other.

Reference numerals 13 and 14 denote a first roller and a second roller which rotate in the cylinders 9 and 10, respectively, and rotate in the cylinder by rotation of the eccentric portions 11 and 12, respectively. 15,
Reference numeral 16 denotes a first frame and a second frame, respectively. The first frame 15 forms a closed compression space of the cylinder 9 between the first frame 15 and the partition plate 8. A closed compression space of the cylinder 10 is formed between the partition 10 and the partition plate 8. The first frame 15 and the second frame 16 are provided with bearings 17 and 18 that rotatably support the lower part of the rotating shaft 6.

Reference numerals 19 and 20 denote discharge mufflers, which are attached so as to cover the first frame 15 and the second frame 16, respectively. The cylinder 9 and the discharge muffler 19 communicate with each other through a discharge hole (not shown) provided in the first frame 15, and the cylinder 10 and the discharge muffler 20 also communicate with the second frame 1.
6 through a discharge hole (not shown).
Reference numeral 21 denotes a bypass pipe provided outside the sealed container 1 and communicates with the inside of the discharge muffler 20.

Reference numeral 22 denotes a discharge pipe provided on the closed container 1, and reference numerals 23 and 24 denote suction pipes connected to the cylinders 9 and 10, respectively. Reference numeral 25 denotes a sealed terminal for supplying electric power to the stator winding 7 of the stator 4 from outside the sealed container 1 (lead wires connecting the sealed terminal 25 and the stator winding 7 are shown in the drawing). Zu).

Reference numeral 26 denotes a rotor core having a thickness of 0.3 mm.
A plurality of rotor iron plates 27 punched out of an electromagnetic steel sheet of about 0.7 mm into the shape shown in FIG. 2 are laminated, and are caulked together and laminated integrally.

The iron plate 27 for the rotor is stamped from an electromagnetic steel plate so as to form magnetic pole portions 28 to 31 constituting four magnetic poles as shown in FIG. At this time, the outer diameter D between the vertices of the magnetic pole portions 28 to 31 is in a range of 30 mm to 70 mm, and is, for example, 50 mm in the embodiment.

Reference numerals 36 to 39 denote four cross-girder-shaped insertion holes provided in the rotor core 26 along the axial direction of the rotating shaft 6. Numerals 40 to 43 denote four flat permanent magnets inserted into the insertion holes 36 to 39.

On the outer peripheral surface of the rotor core 26, there are provided four cutouts S forming a narrow first bridge portion B1 between the insertion holes 36 to 39, and the insertion holes 36 to 39 are provided.
The insertion hole 3 has one end facing the first bridge portion B1 and the other end adjacent to the narrow second bridge portion B2.
6 to 39 are formed in a cross-girder shape to face the side surfaces. Further, the four permanent magnets 40 to 43 are all formed in the same flat plate shape from ferrite or rare earth.

The rotor core 26 is provided with magnetic poles 28-3.
1 and both ends X, Y of the outer peripheral surface and the center O of the rotor 5
The cutout S is formed so that the angle α (magnetic pole angle) formed by the above ranges from 55 degrees to 70 degrees.

Further, end members 48 and 49 for closing the insertion holes 36 to 39 provided at both end surfaces of the rotor core 26, and penetrate the both end members 48 and 49 and the rotor core 26 along the rotation axis direction. There are provided four through holes 50 and rivets 51 integrally forming the end face members 48 and 49 and the rotor core 26 using the through holes 50, and the through holes 50 are provided in the insertion holes 36 to 39. Are provided concentrically inside.

Further, the rotor 5 has the cutout S formed on the outer peripheral surface of the magnetic poles 28 to 31 at the front in the rotation direction.

The bridge portions B1 and B2 formed on both side ends of each of the insertion holes 36 to 39 are formed to have a width of 0.3 mm or more and 0.5 mm or less. The inner diameter of the rotor iron plates 27 at both ends constituting the rotor core 5 is formed to be slightly larger than the inner diameter of the rotor iron plate 27 at the center.

The rotor 5 has the following formulas (1) and (2) when the outer diameter of the rotor core 26 is D, the lamination thickness is L, the thickness of the magnet is t, and the length of the magnet is l. It is configured to satisfy the following. 0.30 <L / D <1.20 (1) 0.02 <t / l <0.20 (2)

Further, a balance weight 57 having an oil separating function is attached to the upper surface of the end face member 48.

In the rotor of the electric motor constructed as described above, one end of each of the insertion holes 36 to 39 faces the first bridge portion B1 and the other end has a narrow second bridge portion B.
Since it is formed in the shape of a girder facing the side surfaces of the insertion holes 36 to 39 adjacent to each other with the 2 interposed therebetween, the magnets can be effectively arranged in a limited space, the characteristics can be improved, and the magnet having a girder shape is protruded. Both the front and back polarities can be used in the part, and the reluctance torque can be used effectively.

Further, since the magnets 40 to 43 are plate-shaped, they can be easily formed and can be of the same shape, thereby improving productivity and promoting cost reduction. The rotor iron core 26 has an angle α (magnetic pole angle) formed between both ends X and Y of the outer peripheral surfaces corresponding to the magnetic poles 28 to 31 and the center O of the rotor 5.
Is in the range of 55 to 70 degrees, the angle of the magnetic pole can be optimized, and the magnetic flux can be used effectively.

The through hole 50 into which the rivet 51 is inserted.
Are magnets 40 to 43 facing between adjacent magnetic poles 28 to 31
And is formed of a ferromagnetic material, so that the characteristics are not degraded.

The bridge portions B1 and B2 formed at the outer peripheral end of each of the insertion holes 36 to 39 are formed to have a width of 0.3 mm or more and 0.5 mm or less. Magnetic leakage can be suppressed.

The inner diameter of the rotor iron plate 27 at both ends of the rotor core 5 is formed slightly larger than the inner diameter of the rotor iron plate 27 at the center. It is possible to suppress a reduction in the inner diameter of the end of the rotor 5 due to a hit.

The rotor 5 has the following formulas (1) and (2) when the outer diameter of the rotor core 26 is D, the lamination thickness is L, the thickness of the magnet is t, and the length of the magnet is l. , The magnets 40 to 43 which are made into common parts are connected to the rotor 5.
Can be incorporated effectively. 0.30 <L / D <1.20 (1) 0.02 <t / l <0.20 (2)

Further, since a balance weight 57 having an oil separating function is attached to the upper surface of the end member 48, an air gap between the rotor 5 and the stator 4 can be provided without providing a separate separating plate. Oil in the refrigerant that rises can be efficiently separated.

The rotor 5 has a cutout S formed on the outer peripheral surface in the rotational direction ahead of the magnetic poles 28 to 31, so that the air gap between the rotor 5 and the stator 4 increases,
Distortion of the magnetic flux waveform on the front side in the rotation direction due to the armature reaction during rotation of the rotor 5 can be suppressed.

The rotor 5 configured as described above has a configuration in which a hole 5a formed at the center of the iron plate 27 for the rotor is shrunk on the rotation shaft 6. Further, the permanent magnet 4 of the above embodiment is used.
Numerals 0 to 43 are made of, for example, a rare earth magnet material such as a praseodymium magnet or a neodymium magnet whose surface is nickel-plated, and have a rectangular shape as described above.

The flat end members 48 and 49 attached to the upper and lower ends of the rotor core 26 are formed of a non-magnetic material such as aluminum or resin material into substantially the same shape as the rotor iron plate 27. I have.

When a direct current is applied to the stator winding 7 of the stator 2, the rotor 5 repels and attracts the magnetic field generated by the permanent magnets 40 to 43.
(E.g., 500 rpm to 1000 rpm by changing the applied voltage)
(Variable within a range of 0 rpm) in the direction of the arrow in FIG. The rotation of the rotor 5 causes the rotation shaft 6 to rotate, which causes the eccentric portions 11 and 12 to rotate.
And the second rollers 13 and 14 rotate, and the compressor exerts a compressing action.

FIG. 3 shows another embodiment, in which end members 48 and 49 for closing insertion holes 36 to 39 provided on both end surfaces of the rotor core 26, and both end members 48 and 49 and the rotor core. 26 along the direction of the rotation axis.
And the end face members 48 and 49 using the through holes 50.
And a rivet 51 integrally forming the rotor core 26 with the rotor core 26. The through-hole 50 is provided concentrically inside the insertion holes 36 to 39, and the center of each of the magnetic poles 28 to 31 is provided with a rotor. An oval air hole 32 to 35 inclined in the anti-rotation direction is provided.

That is, since the oblong air holes 32 to 35 inclined in the direction opposite to the rotation direction are formed, the oil separating effect can be promoted without interrupting the lines of magnetic force and deteriorating the characteristics.

In each of the embodiments, the present invention is applied to a rotor having four magnetic poles. However, the present invention is not limited to this, and the present invention is also effective to a rotor of a motor having four or more poles, such as eight poles. In the embodiment, the rivet 51 is used to set the iron plate 2 for the rotor.
7 are fixed by caulking each other, but not limited thereto, the rotor iron core 26 may be formed by mac bonding using projections or welding.
The present invention is also effective in a case where the upper and lower end face members 48 and 49 are caulked and fixed to the rotor core 26 by the rivets 51.

[0044]

As described in detail above, according to the present invention, the insertion hole 3
Nos. 6 to 39 are formed in a cross-like shape such that one end faces the first bridge portion B1 and the other end faces the side surface of the insertion holes 36 to 39 adjacent to each other across the narrow second bridge portion B2. Therefore, the magnets can be effectively arranged in a limited space, the characteristics can be improved, and both the front and back polarities can be utilized at the protruding magnet portion having a cross-girder shape, and the reluctance torque can be effectively utilized.

Further, since the magnets 40 to 43 are plate-shaped, they can be easily formed and have the same shape, so that productivity can be improved and cost reduction can be promoted.

Further, the rotor core 26 is provided with each of the magnetic poles 28 to 3.
1 and both ends X, Y of the outer peripheral surface and the center O of the rotor 5
Is formed in such a manner that the angle α (magnetic pole angle) between 55 ° and 70 ° is formed, the angle of the magnetic pole can be optimized, and the magnetic flux can be used effectively. .

The through hole 50 into which the rivet 51 is inserted.
Are magnets 40 to 43 facing between adjacent magnetic poles 28 to 31
And is formed of a ferromagnetic material, so that the characteristics are not degraded.

Further, since the cutout S is formed on the outer peripheral surface of the rotor 5 in the rotational direction ahead of the magnetic poles 28 to 31, the air gap between the rotor 5 and the stator 4 becomes large,
Distortion of the magnetic flux waveform on the front side in the rotation direction due to the armature reaction during rotation of the rotor 5 can be suppressed.

Further, since oval air holes 32 to 35 which are inclined in the anti-rotation direction of the rotor are provided at the center of each of the magnetic poles 28 to 31, the magnetic poles 28 to 31 are not obstructed by obstructing the lines of magnetic force and deteriorating the characteristics. The oil separation effect can be promoted.

[Brief description of the drawings]

FIG. 1 is a vertical sectional side view of a compressor to which the present invention is applied.

FIG. 2 is a plan view showing a rotor core of the present invention.

FIG. 3 is a plan view showing a rotor core according to another embodiment of the present invention.

FIG. 4 is a plan view of a rotor showing a conventional example.

[Explanation of symbols]

 Reference Signs List 2 motor 4 stator 5 rotor 6 rotating shaft 26 rotor core 27 rotor iron plate 28-31 magnetic pole 32-35 air hole 36-39 insertion hole 40-47 permanent magnet 50 through hole B1, B2 bridge portion S cutout portion

──────────────────────────────────────────────────続 き Continuation of front page (72) Inventor Kazuhiko Arai 2-5-5-1 Keihanhondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd. (56) References JP-A-9-7429 (JP, A) Hei 5-304736 (JP, A) JP-A-9-23598 (JP, A) WO 92/7409 (WO, A1) (58) Fields investigated (Int. Cl. ⁷ , DB name) H02K 1/27 501 H02K 1/22 H02K 21/00 H02K 29/00

Claims (1)

(57) [Claims] 1. A rotor in which a plurality of rotor iron plates are laminated.
An iron core and this rotor iron core are provided along the axial direction of the rotating shaft.
Four insertion holes, and four insertion holes inserted into these insertion holes.
Sheet-shaped permanent magnets and the outer peripheral surface of the rotor core
A slit that forms a narrow first bridge portion with the insertion hole
The insertion holes are provided at four locations, and one end of the insertion hole is connected to the first block.
A second bridge section opposite the ridge section and having the other end narrow
A girder shape facing the side of the insertion hole adjacent to
The rotor of the electric motor, wherein the rotor
An end face member for closing the insertion holes provided on both end faces of the core,
Multiple that penetrate the end face member and the rotor core along the rotation axis direction
The through-hole, the end face member and the
A rivet integrally formed with the rotor core,
Holes are provided concentrically inside the insertion hole, and each magnetic pole has
In the central part, each magnetic pole outside the through hole has a counter-rotation of the rotor.
That an oval air hole inclined in the rolling direction is provided.
Characteristic motor rotor.