JPH10285881A - Magnet in permanent magnet motor and its formation method - Google Patents

Magnet in permanent magnet motor and its formation method

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Publication number
JPH10285881A
JPH10285881A JP9510897A JP9510897A JPH10285881A JP H10285881 A JPH10285881 A JP H10285881A JP 9510897 A JP9510897 A JP 9510897A JP 9510897 A JP9510897 A JP 9510897A JP H10285881 A JPH10285881 A JP H10285881A
Authority
JP
Japan
Prior art keywords
magnet
coating
motor
concave
electrode
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
JP9510897A
Other languages
Japanese (ja)
Inventor
Yoshihiro Takemura
芳博 竹村
Original Assignee
Nippon Densan Corp
日本電産株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Nippon Densan Corp, 日本電産株式会社 filed Critical Nippon Densan Corp
Priority to JP9510897A priority Critical patent/JPH10285881A/en
Publication of JPH10285881A publication Critical patent/JPH10285881A/en
Withdrawn legal-status Critical Current

Links

Abstract

PROBLEM TO BE SOLVED: To prevent a raised portion of paint generated due to coating on a magnet formed of magnetic powder from being scraped and scattered by interference with a yoke or the like, and to prevent scattering of a paint. Between the magnetic characteristics is prevented from changing. Further, a step required for removing the raised portion, which is performed in the step of forming the magnet, is omitted. SOLUTION: A plurality of recesses 22 for accommodating an electrode at the time of electrodeposition coating, which is a cause of a raised portion, are formed on the surface of a cylindrical magnet body 20, thereby forming the cylindrical magnet body 20. Even if the coating material of the coating concentrates around the electrode contact portion of
By storing the raised portion in the concave portion 22, the paint is prevented from protruding from the magnet surface in the radial direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a permanent magnet motor, and more particularly to an improvement in a magnet used in the permanent magnet motor.

[0002]

2. Description of the Related Art Many OA equipments are used today. For example, a spindle motor is widely used as a rotating device source. As shown in FIG. 9, the spindle motor 1 includes, for example, a bracket 2 fixed to a chassis or frame (not shown), a shaft 3 having a lower end fixed to the bracket 2, and a radial direction of the shaft 3. A stator 4 fixed to the bracket 2 at the outside, a pair of bearings 5 and 5 arranged at a predetermined interval in the longitudinal direction on the shaft 3, and mounted on the bearings 5 and 5, for example. A bearing for supporting a rotating object such as a disk;
, A yoke 7 attached to the rotary hub 6 and rotating together with the hub 6, and a yoke 7 between the yoke 7 and the stator 4 and a slight outer peripheral portion of the stator 4. And a rotor magnet 8 fitted radially inward of the yoke 7 at an appropriate interval.

Here, it is widely known to those skilled in the art that the interval between the stator 4 and the magnet 8 is formed to be extremely narrow (micron unit) in consideration of the rotational efficiency due to the magnetic action.

When manufacturing the magnet 8 used in such a spindle motor 1, generally, first, a magnet having a substantially cylindrical shape having a thickness of, for example, about 1 mm as shown in FIG. The element body 9 is formed. Next, the outer wall surface of the cylindrical magnet body 9 is connected to a plurality of electrodes 10 (usually three or four, but only two are shown in FIG. 10 for ease of illustration). Are arranged at equal angular intervals in the circumferential direction, thereby suspending and holding the magnet element 9, immersing it in a container (not shown) filled with paint, that is, a coating agent, and placing the electrode 1 in the container.
The magnet body 9 is charged through the wire 0 to perform electrodeposition coating, that is, an ED coating 11 on the magnet body 9. This is to prevent the magnetic powder from scattering from the magnet when the magnet manufactured by such a method is rotated. The thickness of the coating 11 formed on the magnet body 9 by this coating operation is usually 25
It is about μm.

After the coating operation is completed, the magnet body 9 is pulled up from the coating agent container while being held by the electrode 10, and dried while the magnet body 9 is suspended. After the magnet body 9 has dried, the electrode 10 is removed from the magnet body 9. When the electrode 10 was removed, the side wall of the magnet body 9 that the electrode 10 was in contact with was painted or coated with a coating material 1.
Pinhole portion to which No. 1 is not attached, that is, defective attachment portion 1
2 occurs. The diameter of this pinhole is about 0.7m
m to about 1 mm. Therefore, it is necessary to repair the ED coating work in order to compensate for the coating agent adhesion defect.

For this reason, the dried magnet element 9
Is placed on a predetermined table, for example, and the coating agent is coated on the magnet body 9. Finally, the magnet 8 is formed by performing a post-processing operation for removing a pool of water and burrs of the coating agent.

In FIG. 10, the electrode 10 supports the outer surface of the magnet body 9. However, the same magnet can be formed by supporting the electrode 10 on the inner surface of the cylindrical magnet body 9.

[0008]

However, in the conventional magnet 8 formed by such a method, when the ED coating is performed in a container filled with a coating agent, a plurality of electrodes 10 are magnetized. Since the body 9 is held, as shown in an enlarged view in FIG. 10, the electrode 1 in contact with the magnet body 9
When the charge concentrates around the tip of the electrode 0, the coating agent collects in a crater shape around the tip of the electrode, and the magnet body 9 is taken out of the coating agent container and dried.
At the portions where the tips of the electrodes 10 are in contact, there are deficient portions of the coating agent, that is, pinholes 12 and projections 13 that form crater-shaped depressions at the center, as well as raised portions 13.

The height of the raised portion 13 is about 0.1 m.
m and its diameter is about 2 mm. Thereafter, when coating is applied to the magnet body 9 to repair the pinhole 12, the defective adhesion portion, that is, the pinhole portion 12 is repaired by a coating agent.
In the swelling portion 13, the coating agent does not fill the swelling portion 13 without coating the swelling portion 1.
Further, a coating agent is laminated on the surface of No. 3. As a result, the swelling portion 13 having a swell of about 0.1 mm at the beginning is further increased by about 0.1 mm, and a swell of about 0.2 mm is formed as a whole.

For this reason, the magnet 8 formed in a state in which the amount of swelling of the mark of the swelling portion 13 is further increased.
When the sheet is inserted into the yoke 7, the raised portion of the paint is scraped off and peeled off, which scatters outside and causes unexpected damage. When the raised portion 13 is formed on the inner surface side of the cylindrical magnet body, the raised portion 13 abnormally approaches the stator 4 to cause a change in magnetic characteristics or contact with the stator 4. There was a problem that the paint in the raised portion was scraped and peeled, and this scattered to the outside.

As a countermeasure for preventing such a problem, before the magnet 8 is pressed into or incorporated into the yoke 7, the raised portion 13 on the outer surface or the inner surface of the cylindrical magnet 8 is adjusted to a predetermined surface shape and size. Although it is conceivable to completely scrape off with a cutter or a file, such work is extremely poor in workability, and there is also a problem that a secondary problem such as cracking or peeling off of paint in other normal parts occurs. there were. SUMMARY OF THE INVENTION An object of the present invention is to provide a magnet for a permanent magnet motor and a method for forming the same, which solves such a problem.

[0012]

A concave portion is formed in an electrode contact portion of a cylindrical magnet body, and even if a coating bulges around the electrode, the bulge portion is accommodated in the concave portion. In this way, a magnet is formed in which the raised portion does not come into contact with portions such as the yoke and the stator.

That is, the present invention relates to a method for forming a magnet in a permanent magnet motor, comprising forming a cylindrical magnet body having a predetermined thickness using magnetic powder; Forming a plurality of electrode contact portions each having a concave portion, and completely immersing the magnet element in a coating agent solution in a container filled with a coating agent in a state where the electrode is in contact with the concave portion, Charging the magnet body through the electrodeposition coating of the coating agent on the magnet body, coating the coating on the electrode contact portion of the magnet body, comprising the steps of: It has an area and a depth capable of completely accommodating the swelling of the coating agent generated in the electrode contact portion during the electrodeposition coating.

The present invention also provides a stationary member, a rotating member rotatably supported by the stationary member via a bearing, a stator disposed on the stationary member, and a diameter of the stator of the rotating member. In a permanent magnet motor having a substantially cylindrical magnet fitted to a portion opposed in the direction, the magnet is formed by molding using magnetic powder, and the surface of the coating agent is coated by electrodeposition coating. A coating layer is formed, and a plurality of recesses are formed on the surface of the magnet to be brought into contact with electrodes during electrodeposition coating.

Further, the magnet according to the present invention has a substantially cylindrical shape, is used for a permanent magnet motor, and is formed by molding using magnetic powder, and a magnet formed on the surface of the magnet body. The magnet has a concave portion to which an electrode is brought into contact during electrodeposition coating, and a coating layer of a coating agent formed on the surface of the magnet body by electrodeposition coating.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention relates to a magnet used for a permanent magnet motor. An embodiment of the present invention will be described by taking as an example a case where the magnet is used for a spindle motor as shown in FIG.

FIG. 1 shows a first embodiment of the present invention. In FIG. 1, reference numeral 20 denotes a cylindrical magnet body similar to the magnet body 9 shown in FIG. 10 formed by a predetermined magnetic powder. This magnet body 20 is different from the conventional magnet body 9 having a perfect cylindrical shape, and has, for example, three grooves 22 as recesses extending over the entire length in the longitudinal direction at the outer surface thereof at equal angular intervals. It is formed in such a position. The number of the grooves 22 is
The number is selected so as to be equal to the number of electrodes (not shown) for suspending and holding the magnet body 20 during the ED coating operation described later. Therefore, when three electrodes are used, three grooves 22 are formed on the outer peripheral surface of the magnet body 20 at an angle of 120 ° from each other, and when four electrodes are used, four grooves 22 are formed. Are formed at an angle of 90 degrees.

Here, the width a on the outer peripheral surface of each groove is about 2 mm to 3 mm, and the depth depth, that is, the diameter dimension b is about 0.2 mm to 0.3 mm. Further, it is desirable that the thickness in the diametric direction, that is, the bottom thickness c in the groove portion of the magnet body 20 is selected to be at least 0.5 mm. Therefore, the thickness d of the portion of the magnet body 20 where the groove 22 is not provided is at least 0.8 mm
It is desirably about 1.5 mm, preferably about 1.0 mm to 1.2 mm.

After preparing such a magnet body 20, a groove 22 on the outer wall surface of the cylindrical magnet body 20 is formed.
Preferably, one electrode similar to the electrode 10 shown in FIG. 10 is arranged one by one slightly above the middle part in the longitudinal direction. Thereafter, the magnet body 20 is suspended and held by these electrodes, carried to a container (not shown) filled with paint, that is, a coating agent, and then the magnet body 20 is settled in the container. The magnet body 20 is guided by the electrodes until the magnet body 20 is completely buried in the coating solution in the container. Thereafter, the magnet body is charged through the electrode by the known procedure as described above, and the magnet body 2 is charged.
0 is provided with an electrodeposition coating known per se, ie an ED coating.

By this coating operation, a coating having a uniform thickness is formed on the entire surface of the cylindrical outer surface and the cylindrical inner surface including the groove portion 22 of the magnet body 20.
The thickness of the coating formed at this time is about 25 μm. After the coating operation is completed, the magnet body 20 is taken out of the coating agent dissolving device by the electrode and dried while the magnet body 20 is suspended. After the magnet body 20 has dried, the electrodes are removed from the magnet body 20. Magnet element 2 with which the tip of the electrode was in contact when the electrode was removed
A pinhole portion where no paint, that is, a coating agent is not adhered, that is, a portion where adhesion is insufficient, is generated in a part of each of the grooves 22 of zero. The diameter of this pinhole is about 0.7 as described above.
mm to about 1 mm.

Therefore, in order to repair the coating material adhesion defect, the dried magnet body 20 is placed on a predetermined table or the like as described above, and the coating material is applied by spraying or brushing. Thus, a magnet is formed.

The magnet formed according to the first embodiment of the present invention can be applied to the spindle motor 1 as an example of the permanent magnet motor described with reference to FIG. The spindle motor 1 includes a bracket 2 as a stationary member, a fixed shaft 3 having one end fixed to a circular opening provided at the center of the bottom of the bracket 2, and a bearing 5 fitted to the fixed shaft 3. , 5 and the bearing 5,
A hub 6 rotatably fitted to the fixed shaft 3 via the bracket 5, a stator 4 attached to the bracket 2, and a magnet 8 attached to the hub 6 via the yoke 7 so as to face the stator 4. It has.

In such a spindle motor 1,
By using the magnet according to the present invention, the raised portion caused by coating the magnet 8 is completely accommodated in the groove 22 on the outer surface of the magnet body 20, and the raised portion is inserted into the yoke 7. It is possible to prevent the paint that has been scraped off and peeled off and scattered to the outside.

Furthermore, if the groove 22 is formed on the fitting surface to the hub 6, the groove can be closed by incorporating the magnet 8 into the yoke 7, so that the exposed surface does not have irregularities, and the groove for dust and the like is not formed. Not only does it not penetrate into the shaft, but also smooth rotation can be expected because no air resistance is generated by the groove during rotation.

FIG. 2 shows a second embodiment of the present invention. 2, reference numeral 30 denotes a cylindrical magnet body similar to the magnet body 20 of FIG. This magnet element 30 differs from the magnet element 20 shown in FIG. 1 in that in the first embodiment, the cylindrical magnet element 20 has a groove 2 as a concave portion on its outer surface side.
2, the second embodiment shown in FIG. 2 is that the cylindrical magnet body 30 has a groove 32 as a recess on the inner surface side. Here, the grooves 32 have the same numbers and dimensions as those described for the grooves 22. The second embodiment is advantageous when the electrodes suspend the magnet body 30 from the inner surface side of the magnet body 30.

The magnet shown in FIG. 2 can also be applied to the spindle motor 1 shown in FIG. Also in this case, the raised portion caused by the coating on the magnet 8 is completely housed in the groove 32 on the surface of the magnet body 30, so that the raised portion abnormally approaches the stator 4 and the magnetic characteristics fluctuate. Or it comes off and comes into contact with the stator 7 when the motor rotates,
It is also possible to prevent the peeled paint from scattering outside.

FIG. 3 shows a third embodiment of the present invention. In FIG. 3, reference numeral 40 denotes a cylindrical magnet body in a form in which the magnet body 20 of FIG. 1 and the magnet body 30 of FIG. 2 are combined. This cylindrical magnet body 40 has a plurality of grooves 42 as recesses in FIG.
2 in that the grooves 44 are provided on the outer surface side of the magnet body 40, and a plurality of grooves 44 as recesses are provided on the inner surface side of the magnet body 40, as in the embodiment of FIG. 1 and FIG. Here the groove 42
The groove 44 and the groove 44 are arranged so as to be at positions offset by the same angle. In addition, these grooves 42, 44
Have the same numbers and dimensions as described for the grooves 22 shown in FIG. In this embodiment, the electrodes can be mounted from the inner surface side or the outer surface side of the tubular magnet body 40, and furthermore, some electrodes can be mounted on the magnet body 40.
This has the advantage that it can also be used when it is desired to mount some of the remaining electrodes on the inner surface side and on the outer surface side.

FIG. 4 shows a fourth embodiment of the present invention. This embodiment is an improvement of the first embodiment shown in FIG. In the magnet body 20 shown in FIG. 1, the groove extends over the entire length of the body 20 in the longitudinal direction. However, in the magnet body 50 of this embodiment, only a portion where the electrode abuts forms a part of the groove. The recess 52 is only formed on the outer surface side. These recesses 52 are provided in the grooves 22.
Are arranged in the same angular relationship as described above, and are arranged at a position slightly above the middle portion of the magnet body 50 in the longitudinal direction. Thereby, the magnet body 50 can be held in a stable state in a substantially vertical state. These recesses 52 have the same size in the circumferential direction as in FIG. 1A, the size in the axial (longitudinal) direction is e, and the depth in the circumferential direction is the same as b in FIG. You can do it. Here, e is approximately equal to a, but may be larger or smaller. Of course, the shape of the concave portion 52 is not limited to a rectangular shape as shown in the figure, and in consideration of the fact that the raised portion of the coating agent forms a crater shape, for example, the diameter is about 2 mm to 3 mm, and the depth is about 2 mm to 3 mm. It is also possible to form a concave portion having a circular cross section of about 0.2 mm to 0.3 mm. In this embodiment, it is not necessary to form the concave portion 52, which is the electrode receiving portion, over the entire length of the magnet body as shown in FIG. 1, and there is an effect of suppressing a decrease in the magnetic properties of the magnet.

FIG. 5 shows a fifth embodiment of the present invention. Cylindrical magnet body 6 according to this embodiment
0 is substantially the same as the embodiment of FIG. 4 except that the concave portion 62 is provided on the inner surface side of the cylindrical magnet body 60. In this embodiment, a concave portion 6 serving as an electrode receiving portion is used.
2 does not need to be formed over the entire length of the magnet body as shown in FIG. 1, and furthermore, the electrodes suspend the magnet body 60 from the inner surface side of the magnet body 60 as in the embodiment of FIG. It is advantageous when you do. Also in this embodiment, the concave portion 62 has, for example, a diameter of about 2 mm to 3 mm and a depth of about 0.2 mm to 0.
It is also possible to form a recess having a circular cross section of about 3 mm.
This embodiment has an effect of suppressing a decrease in magnetic characteristics as in the embodiment of FIG.

FIG. 6 shows a sixth embodiment of the present invention. This embodiment is an improvement of the fourth embodiment shown in FIG. In the magnet body 50 shown in FIG. 4, the concave portion 52 for receiving an electrode is formed slightly above the middle part in the longitudinal direction of the body 50, but in the magnet body 70 according to the sixth embodiment, such a recess is formed. A concave portion 72 is arranged at an outer surface side end of the element body 70. These recesses 72 have the same angular relationship as in the above embodiments, and their dimensions are the same as the dimensions of the recesses 52 of the magnet body 50 in FIG. This embodiment has an effect of suppressing the deterioration of the magnetic characteristics as in the embodiments of FIGS. Also in this embodiment, the concave portion 72 has a diameter or a short diameter of at least about 2 mm to 3 m in addition to the rectangular shape as shown.
m, a concave portion having a semicircular or elliptical cross section with a depth of about 0.2 mm to about 0.3 mm is also possible.

FIG. 7 shows a seventh embodiment of the present invention. This embodiment is an improvement of the fifth embodiment shown in FIG. In the magnet body 60 shown in FIG. 5, the concave portion 62 for receiving the electrode is formed slightly above the middle part in the longitudinal direction of the body 60, but in the magnet body 80 according to the seventh embodiment, such a recess is formed. A concave portion 82 is arranged at the inner surface side end of the element body 80. These recesses 82 have the same angular relationship as in the above embodiments, and their dimensions are the same as the dimensions of the recesses 62 of the magnet body 60 in FIG. This embodiment also has the effect of suppressing a decrease in magnetic characteristics, as in the embodiments of FIGS. Also in this embodiment, the concave portion 82 has a diameter or a short diameter of at least about 2 mm to 3
It is also possible to use a semicircular or elliptical cross-section having a depth of about 0.2 mm to 0.3 mm.

FIG. 8 shows an eighth embodiment of the present invention. 8, reference numeral 90 denotes a cylindrical magnet element in which the magnet element 70 of FIG. 6 and the magnet element 80 of FIG. 7 are combined. This cylindrical magnet body 90 has a plurality of recesses 92 at the outer surface side end of the magnet body 90 as in the embodiment of FIG. 6, and a plurality of recesses 94 as in the embodiment of FIG. Body 90
6 and 7 in that they are respectively provided at the inner surface side end portions. Here, the concave portion 92 and the concave portion 94
Are arranged so as to be at positions deviated by an equal angle from each other. In addition, these concave portions 92 and 94 are provided in FIG.
Or it has similar numbers and dimensions as described for the recesses 72, 82 shown in FIG. This embodiment is shown in FIGS.
As in the embodiment, there is an effect that the deterioration of the magnetic characteristics is suppressed. Further, electrodes can be attached from the inner surface side or the outer surface side of the tubular magnet body 90, and some of the electrodes can be attached to the inner surface side of the magnet body 90 and the other can be attached There is an advantage that it can be used also when it is desired to attach the outer surface side. Also in this embodiment, the recess 9
2 and 94 have a diameter or a short diameter of at least about 2 mm to 3 mm and a depth of about 0.2 mm in addition to the rectangular shape as shown.
It is also possible to form a concave portion having a semicircular or elliptical cross section of about mm to 0.3 mm.

Although not shown, the embodiment of FIG. 4 and the embodiment of FIG. 5 are synthesized, and the concave portions are shifted by the same angle on the outer surface side and the inner surface side of the cylindrical magnet body, respectively. Obviously, it is possible to use a magnet body formed in a position. In this embodiment, as in the case of FIGS. 3 and 8, electrodes can be attached from the inner surface side or the outer surface side of the tubular magnet body, and furthermore, some of the electrodes can be attached to the magnet body. There is an advantage that it can also be used when it is desired to mount the remaining electrodes on the inner surface side of the body and on the outer surface side.

In the above description, as the permanent magnet motor to which the magnet is mounted, the spindle motor in which the magnet is mounted on the hub via the yoke with the shaft fixed is described. However, the present invention relates to a shaft rotating type permanent magnet motor. Alternatively, even when the yoke is not interposed by using an iron hub, the same effect can be obtained by using the magnet according to the present invention. It is clear that the permanent magnet motor can be applied not only to the outer rotor type described in FIG. 9 but also to an inner rotor type.

[0035]

According to the present invention, in the case of ED coating, a projection which forms a crater-shaped recess having a height of about 0.1 mm and a diameter of about 2 mm, for example, around the tip of the electrode which is in contact with the magnet element. A bulge is formed, and the height of the raised portion is reduced to about 0.
Even if it is increased to 2 mm, in the magnet body of the present invention,
The raised portion is generated inside a concave portion having a width a of about 2 mm to 3 mm and a depth b of about 0.2 mm to 0.3 mm, for example. Therefore, the raised portion is housed in the concave portion, and is completely prevented from protruding from the circumferential surface of the magnet in the radial direction. Therefore, even if the magnet according to the present invention is inserted into a yoke or the like immediately after molding, the raised portion does not come into contact with the yoke or the like, and the magnet can be securely fitted to the yoke or the like in a tightly fitted state. Eliminates the need for manual work to remove the swelling part with poor workability,
Therefore, it is possible to completely prevent the secondary problem that the coating of the normal portion is peeled off by the manual operation. Especially,
If the recess is opened to the end face of the magnet body,
The structure of the mold for forming the magnet body is relatively simple,
Molding becomes easy.

In the magnet according to the present invention and the permanent magnet motor using the magnet, since the raised portion is completely accommodated in the concave portion, the paint of the raised portion generated on the outer surface side of the magnet is applied to the yoke. In addition to preventing problems such as chipping and peeling during insertion into the magnet etc., even if it occurs on the inner surface side of the magnet, the raised portion abnormally approaches the stator and the magnetic characteristics fluctuate or It is also possible to prevent such a problem that the motor comes into contact with the stator during the rotation of the motor and is scraped off. In particular, if the concave portion is formed on the fitting surface of the rotating member, the concave portion can be closed by incorporating the magnet into the rotating member, so that the exposed surface does not have unevenness and there is no entry of dust and the like into the concave portion. In addition, smooth rotation can be expected because no air resistance is generated by the concave portion during rotation.

[Brief description of the drawings]

FIG. 1 is an overall perspective view of a cylindrical magnet body showing a first embodiment of the magnet of the present invention.

FIG. 2 is a partial perspective view of a cylindrical magnet body showing a second embodiment of the magnet of the present invention.

FIG. 3 is an overall perspective view of a cylindrical magnet body showing a third embodiment of the magnet of the present invention.

FIG. 4 is a partial perspective view of a cylindrical magnet body showing a fourth embodiment of the magnet of the present invention.

FIG. 5 is a partially broken perspective view of a cylindrical magnet body showing a fifth embodiment of the magnet of the present invention.

FIG. 6 is a partial perspective view of a cylindrical magnet body showing a sixth embodiment of the magnet of the present invention.

FIG. 7 is a partial perspective view of a cylindrical magnet body showing a seventh embodiment of the magnet of the present invention.

FIG. 8 is a partial perspective view of a cylindrical magnet body showing an eighth embodiment of the magnet of the present invention.

FIG. 9 is a cross-sectional view of a known spindle motor as an example of a permanent magnet motor.

FIG. 10 is a view showing a known process for forming a magnet used for assembling a permanent magnet motor.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Electrode 11 Coating layer 12 Pinhole 13 Raised part 20, 30, 40, 50, 60, 70, 80, 90 Magnet element 22, 32, 42, 44 Groove 52, 62, 72, 82, 92, 94 Concave part

Claims (11)

[Claims]
1. A method for forming a magnet in a permanent magnet motor, comprising forming a cylindrical magnet body having a predetermined thickness using magnetic powder, comprising a concave portion on a surface of the magnet body. Forming a plurality of electrode contact portions, completely burying the magnet body in a coating agent solution in a container filled with a coating agent in a state where the electrodes are in contact with the concave portions, and magnetizing the magnet body through the electrodes; Charging the element body and electrodepositing the coating agent on the magnet element body, and coating the electrode contact portion of the magnet element with a coating agent. The permanent magnet motor is characterized in that it has an area and a depth that can completely accommodate the swelling of the coating agent generated in the electrode contact portion at the time of How to formed.
2. The method for forming a magnet in a permanent magnet motor according to claim 1, wherein the number of recesses in the magnet body is at least as large as the number of electrodes that are in contact.
3. A magnet for a permanent magnet motor according to claim 1, wherein a concave portion with which the electrode abuts is provided on one or both of an inner surface side and an outer surface side of the cylindrical magnet body. how to.
4. The method for forming a magnet in a permanent magnet motor according to claim 1, wherein the concave portion is provided on a peripheral surface of the magnet body.
5. The method for forming a magnet in a permanent magnet motor according to claim 1, wherein the recess is disposed on a peripheral surface of the magnet body and is opened on at least one end face of the magnet body. .
6. A stationary member, a rotating member rotatably supported by the stationary member via a bearing, a stator disposed on the stationary member, and radially opposed to the stator of the rotating member. A magnet having a substantially cylindrical shape fitted to a part thereof, wherein the magnet is formed by molding using magnetic powder, and a coating layer of a coating agent is formed on the surface by electrodeposition coating. A permanent magnet motor, wherein a plurality of recesses are formed on the surface of the magnet to be brought into contact with electrodes during electrodeposition coating.
7. The permanent magnet motor according to claim 6, wherein the recess is opened at least on one end surface of the magnet.
8. The apparatus according to claim 6, wherein the recess is formed on a surface of the magnet that is fitted to the rotating member.
A permanent magnet motor according to claim 1.
9. A magnet body having a substantially cylindrical shape, used for a permanent magnet motor, and formed by molding using magnetic powder, and an electrode formed on the surface of the magnet body during electrodeposition coating. A magnet, comprising: a concave portion with which a contact is made; and a coating layer of a coating agent formed on the surface of the magnet body by electrodeposition coating.
10. The magnet according to claim 9, wherein a plurality of the concave portions are formed on the surface of the magnet body at equal intervals in a circumferential direction.
11. The magnet according to claim 9, wherein the recess is opened at least on one end surface of the magnet.
JP9510897A 1997-03-28 1997-03-28 Magnet in permanent magnet motor and its formation method Withdrawn JPH10285881A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP9510897A JPH10285881A (en) 1997-03-28 1997-03-28 Magnet in permanent magnet motor and its formation method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP9510897A JPH10285881A (en) 1997-03-28 1997-03-28 Magnet in permanent magnet motor and its formation method

Publications (1)

Publication Number Publication Date
JPH10285881A true JPH10285881A (en) 1998-10-23

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Family Applications (1)

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Country Status (1)

Country Link
JP (1) JPH10285881A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001320842A (en) * 2000-05-10 2001-11-16 Sankyo Seiki Mfg Co Ltd Laminated core and method for manufacturing it
EP1176700A2 (en) * 2000-07-27 2002-01-30 Yamaha Hatsudoki Kabushiki Kaisha Embedded magnet type rotor, manufacturing method and mold device
CN102723164A (en) * 2012-06-04 2012-10-10 江苏多维科技有限公司 Groove-shaped permanent magnet and magnetic sensor with same

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001320842A (en) * 2000-05-10 2001-11-16 Sankyo Seiki Mfg Co Ltd Laminated core and method for manufacturing it
EP1176700A2 (en) * 2000-07-27 2002-01-30 Yamaha Hatsudoki Kabushiki Kaisha Embedded magnet type rotor, manufacturing method and mold device
EP1176700A3 (en) * 2000-07-27 2004-02-04 Yamaha Hatsudoki Kabushiki Kaisha Embedded magnet type rotor, manufacturing method and mold device
US6826824B2 (en) 2000-07-27 2004-12-07 Yamaha Hatsudoki Kabushiki Kaisha Embedded magnet type rotor and filling of the same
CN102723164A (en) * 2012-06-04 2012-10-10 江苏多维科技有限公司 Groove-shaped permanent magnet and magnetic sensor with same

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