JP2526141Y2 - Permanent magnet rotor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention is used for an adduction type brushless motor in which a rotor is surrounded by a stator, and has a segment magnet and a rotor. The present invention relates to a permanent magnet rotor whose most part except a shaft is covered with a molding resin layer.

[Conventional technology]

In this type of permanent magnet rotor, the segment magnets must be securely held even when rotated at a high temperature and at a high speed. The applicant of the present invention has proposed a permanent magnet rotor having the structure shown in FIGS. 7 and 8 in Japanese Patent Application No. 01-71010 as satisfying such a demand.

This is fixed to the rotor shaft 1 and the outer periphery of the rotor shaft 1, and is basically cylindrical and has holding projections 2a to 2d projecting radially from the outer peripheral surface 2s thereof. And a yoke 2 made of a magnetic material having a plurality of through holes 2e to 2h in the axial direction, an outer peripheral surface 2s of the yoke 2 having an arc plate shape, and a holding projection 2a.
A plurality of segment magnets 3a to 3d housed in a space formed by the side surfaces of the yoke 2 and the segment magnets 3a to 3d, and are mounted on the rotor shaft 1 so as to sandwich the axial side surfaces of the yoke 2 and the segment magnets 3a to 3d. And has an outer diameter substantially equal to or slightly smaller than the outer diameter of the holding projections 2a to 2d, and
A resin control plate 4 made of a nonmagnetic material having through holes 4e to 4h corresponding to the through holes 2e to 2h, an axially outer surface of the resin control plate 4, an outer peripheral surface continuous with the resin control plate 4, and segment magnets 3a to 3h.
A molding resin layer 5 of a thermosetting resin is formed in a gap between 3d and the holding projections 2a to 2d and in both through holes 2e to 2h and 4e to 4h of the yoke 2 and the resin control plate 4.

[Problems to be solved by the invention]

Although the permanent magnet rotor described above can sufficiently secure the holding strength of the segment magnet, it has some problems in productivity.

That is, both through holes 2e through 2e of the yoke 2 and the resin control plate 4
For the centering of 2h, 4e to 4h, the press-fitting process of the resin control plate 4 to the rotor shaft 1 is troublesome, and even if the press-fitting process is performed, the press-fitting strength cannot be increased so much. There is a risk that the core will be misaligned before molding. Further, in the forming process, the respective segment magnets 3a to 3d are positioned in the center between the holding projections in a well-balanced manner.
Since the molding resin layer 5 of about 0.1 to 0.3 mm must be formed on the outer periphery of 3a to 3d, the number of gates of the molding die is the same as the number of the segment magnets 3a to 3d, and the position is the position of each of the segment magnets 3a to 3d. Since it is desirable to be located at the center in the circumferential direction, it is troublesome to mount components on the mold for that purpose.

The present invention has been made in view of the above circumstances, and its purpose is to ensure that the permanent magnet is securely held, and that the centering of both through holes of the yoke and the resin control plate can be easily performed. Another object of the present invention is to provide a permanent magnet rotor in which a component to be mounted on a mold can be suitably positioned easily, thereby improving productivity.

[Means for solving the problem]

In order to solve such a problem, a permanent magnet rotor according to claim 1 is fixed to a rotor shaft and an outer periphery of the rotor shaft, and is basically cylindrical and has an outer periphery. A yoke made of a magnetic material having a holding projection that is radially protruded from the surface and has a width extending from near the middle of the radial height to the tip, and having a plurality of through holes in the axial direction, and an arc plate shape. A plurality of segment magnets accommodated in a space formed by the outer peripheral surface of the non-yoke and the side surfaces of the holding projections, and are mounted on the rotor shaft so as to sandwich the yoke and the axial side surfaces of the segment magnets, A resin control plate made of a non-magnetic material having an outer diameter substantially equal to or slightly smaller than the outer diameter of the holding protrusion, and having a through hole corresponding to the through hole of the yoke, and an axially outer surface of the resin control plate, Peripheral surface and segment connected to this In a permanent magnet rotor in which a molded resin layer of a thermosetting resin is formed in a gap between a stone and a holding protrusion and a through hole of a yoke and a resin control plate, a yoke is formed around the through hole of the resin control plate. It has a configuration in which a cylindrical projection that fits into the through hole is provided.

According to a second aspect of the present invention, there is provided a permanent magnet rotor having a height protruding from the molded resin layer on an end surface of the resin control plate opposite to the cylindrical projection in the permanent magnet rotor according to the first aspect. It is configured to have projections.

[Action]

In the permanent magnet rotor according to the present invention, when the resin control plate is press-fitted into the rotor shaft and is roughly positioned and press-fitted, the cylindrical protrusion of the resin control plate becomes a through hole of the yoke. And the two are not detached from each other, so that the centering of both the through-holes of the yoke and the resin control plate can be surely and easily performed.

According to the permanent magnet rotor described in claim (2), the same operation and effect as those described in claim (1) can be obtained.
Since the protrusions of the molding resin layer can be positioned by the molding die, it is easy to suitably position the components to be mounted on the die.

〔Example〕

Hereinafter, an embodiment of the present invention will be described with reference to FIG. 1 and FIG. Note that the same reference numerals are given to members that are substantially the same as the members described in the conventional example.

The permanent magnet rotor includes a rotor shaft 1, a yoke 2, a plurality (four in this embodiment) of segment magnets 3a to 3d, resin control plates 14, 14 made of a nonmagnetic material, and a resin layer of a thermosetting resin. And 5.

The yoke 2 is formed by laminating pieces formed by punching out a magnetic material such as a silicon steel plate, and is fixed to the outer periphery of the rotor shaft 1, and has a basically cylindrical shape. This laminated thickness is substantially equal to the axial length of the segment magnets 3a to 3d described later. Further, holding projections 2a to 2d of the same number as the segment magnets and having a height substantially equal to the thickness in the radial direction are radially provided on the outer peripheral surface 2s of the yoke 2. The holding projections 2a to 2d are wider from near the middle of the radial height to the tip. Therefore, the outer peripheral surface 2s
And the side surfaces of the holding protrusions 2a to 2d form substantially arc-shaped spaces S1 to S4. 2e to 2h are through holes for molding and for forming a molded resin layer.

Each of the segment magnets 3a to 3d has a circular plate shape slightly smaller than the segment magnets 3a to 3d so as to be accommodated in the spaces S1 to S4 of the yoke 2. Therefore, the outer peripheral side of both ends in the circumferential direction has a shape in which a portion corresponding to the wide shape of the holding protrusion is cut off. The same number of the segment magnets 3a to 3d, which are magnetized in the radial direction and have an inverse relationship to each other, are prepared and accommodated in the spaces S1 to S4 so that different poles appear alternately on the outer periphery.

The resin control plates 14, 14 made of a non-magnetic material are an essential part of the present invention. The nonmagnetic discs 14, 14 are mounted on the rotor shaft 1 so as to sandwich the yoke 2 and the axial side surfaces of the segment magnets 3a to 3d. Projection 2a ~
It is formed in a disk shape having an outer diameter substantially equal to or slightly smaller than the outer diameter of 2d. Therefore, in the center thereof, the rotor shaft 1 has press-fit holes 14a, 14a having an inner diameter slightly smaller than the outer diameter. Also, the through holes 14e to 14h for molding and molding the resin layer are formed corresponding to the through holes 2e to 2h of the yoke 2. Around the through holes 14e to 14h, there are provided cylindrical projections 14j to 14m to be fitted (substantially the same diameter) to the through holes 2e to 2h of the yoke 2.
The tips of the cylindrical projections 14j to 14m are desirably chamfered or rounded.

The molded resin layer 5 includes an axially outer surface of the resin control plates 14 and 14 and an outer peripheral surface continuous with the resin control plates 14 and 14, a gap between the segment magnets 3 a to 3 d and the holding protrusions 2 a to 2 d, and the yoke 2 and the resin control plate.
The through holes 2e to 2h and 14e to 14h are formed by injection molding a thermosetting resin such as an unsaturated polyester resin.

The manufacture of the permanent magnet rotor is performed as follows. First, the yoke 2 is pressed into the rotor shaft 1. Next, the segment magnets 3a to 3d are accommodated in the spaces S1 to S4 of the yoke 2. Next, resin control plates 14 and 14 are press-fitted to both axially outer surfaces of the yoke 2 so as to sandwich the outer surfaces. In this case, the cylindrical projections 14j to 14m are formed in the through holes 2e to 2h of the yoke 2.
Fits. This state is mounted on a molding die, and a thermosetting resin is injected.

Next, another embodiment of the present invention will be described with reference to FIGS. 3 and 6. FIG. It should be noted that only the resin control plate is different from the previous embodiment, and the other members are denoted by the same reference numerals as those in the previous embodiment, and detailed description is omitted.

The resin control plate 24 of this embodiment is provided with protrusions 24a and 24b having a height protruding from the molded resin layer 5 on the end surface opposite to the cylindrical protrusions 14j to 14m of the resin control plate 14 of the previous embodiment. It becomes. The projections 24a and 24b are cylindrical projections 14j to 14j.
m, that is, the resin control plate 14 is formed by a molding die so as to be at a fixed position with respect to the through holes 14e to 14h. The upper and lower molds of the mold for the permanent magnet rotor are provided with recesses into which the molds fit, whereby the gate position of the mold is set at a suitable position, for example, the center of each of the segment magnets 3a to 3d in the circumferential direction. It can be located nearby.

[Effect of the invention]

Since the permanent magnet rotor of the present invention is configured as described above, the following effects can be obtained.

Since the permanent magnet rotor is obtained by molding with a resin, it is easy to manufacture the permanent magnet rotor, and the permanent magnet can be reliably held in the radial and circumferential directions by the holding projections. Since it is completely covered with the molding resin layer, it can be protected from external force or even if it should be damaged, it will not be scattered.In addition, when press-fitting the resin control plate to the rotor shaft, Approximately positioning and press-fitting, the cylindrical protrusion of the resin control plate fits so as to be guided by the through-hole of the yoke, and there is no detachment after that. Centering can be performed easily and reliably.

According to the second aspect, the same operation and effect as those of the first aspect can be obtained. In addition, since the protrusion of the resin control plate can be positioned by the molding die, it is mounted on the die. Suitable positioning of the parts can be facilitated.

Therefore, the permanent magnet rotor of the present invention can securely hold the permanent magnet, can easily center the through-holes of the yoke and the resin control plate, and can easily mount parts to the mold. Positioning can be easily performed, and thus productivity can be improved.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment (first embodiment) of the invention according to claim (1), FIG. 2 is an exploded perspective view before the formation of a molding resin layer, and FIG. FIG. 4 is a longitudinal sectional view showing one embodiment (another embodiment) of the invention described in claim (2); FIG. 4 is a perspective view cut into a plurality thereof; 6, FIG. 6 is an exploded perspective view before the molding resin layer is formed, FIG. 7 is a perspective view cut into a plurality showing a conventional example, and FIG. 8 is a cross sectional view thereof. 1 ... rotor shaft, 2 ... yoke, 2e to 2h ... through hole,
3a to 3d: Segment magnet, 14, 24: Resin control plate, 1
4e to 14h: through-hole, 14j to 14m: cylindrical projection, 24
a, 24b: Projection, 5: Molded resin layer of thermosetting resin.

 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Toshihiro Sakamoto 1048 Odakadoma, Kadoma City, Osaka Prefecture Matsushita Electric Works, Ltd. (JP, U) Japanese Utility Model Showa 63-10761 (JP, U) Japanese Utility Model Showa 64-25876 (JP, U)

Claims (2)

(57) [Scope of request for utility model registration] 1. A rotor shaft, which is fixed to the outer periphery of the rotor shaft, and is basically cylindrical and protrudes radially from the outer peripheral surface thereof, and is provided near the middle of the radial height. A space formed by a yoke made of a magnetic material having a holding protrusion that is widened toward the tip and having a plurality of through holes in the axial direction, an arc-shaped plate, and an outer peripheral surface of the yoke and a side surface of the holding protrusion. A plurality of segment magnets housed in the
A through hole which is mounted on the rotor shaft so as to sandwich the axial side surface of the yoke and the segment magnet, has an outer diameter substantially equal to or slightly smaller than the outer diameter of the holding projection, and corresponds to a through hole of the yoke. A resin control plate made of a nonmagnetic material having a, an axially outer surface of the resin control plate, an outer peripheral surface continuous with the resin control plate, a gap between the segment magnet and the holding protrusion, and a through hole of the yoke and the resin control plate, A permanent magnet rotor having a molded resin layer of a thermosetting resin, wherein a cylindrical projection fitted around the through hole of the yoke is provided around the through hole of the resin control plate. Rotor. 2. The permanent magnet rotor according to claim 1, wherein a protrusion having a height protruding from the molded resin layer is provided on an end surface of the resin control plate opposite to the cylindrical protrusion.