JP2005027480A - Magnet magnetizer and magnet magnetizing method for rotary electric machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a magnet magnetizer capable of surely preventing a high voltage from occurring between both ends of a coil, even if an induced electromotive force is caused to occur to the coil affected by magnetizing magnetic field for magnetizing a magnetic substance. <P>SOLUTION: A capacitor 25 is provided that, when magnetizing, is connected between both ends of an armature coil 7 and charges potential so as to suppress the increase of a voltage between both ends of the armature coil 7 based on the induced electromotive force that occurs to the armature coil 7, affected by the magnetizing magnetic field. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a magnet magnetizing device for a rotating electrical machine and a magnet magnetizing for the rotating electrical machine, wherein the magnetic body mounted inside the rotating electrical machine is magnetized from the outside to change into a magnet after the assembly. Regarding the method.

  Various techniques have been proposed for applying a magnetizing magnetic field from the outside to a magnet after the rotating electrical machine is assembled to change it into a magnet. When this technique is used, it is not necessary to use a magnet that has already been magnetized, so that foreign matter such as iron powder can be prevented from entering the rotating electrical machine, leading to an improvement in the quality of the rotating electrical machine.

  As a technique for magnetizing the magnetic body after assembling in this way and changing it to a magnet, for example, it is disclosed in Patent Document 1, and in Patent Document 1, the magnet of the coil assembly constituting the vehicle speed sensor is disclosed. A magnetizing method is shown. The coil assembly includes an electromagnetic coil and a magnetic body that becomes a magnet when magnetized, and a magnetic field is applied to the magnetic body by a magnetizing device to change the magnetic body into a magnet. .

  By the way, when a magnetizing magnetic field is applied to a magnetic body, a magnetizing magnetic field is similarly applied to the electromagnetic coil, so that an induced electromotive force is generated in the electromagnetic coil, and a high voltage is generated at both ends of the coil. At this time, for example, if the coating of the conducting wire constituting the electromagnetic coil is damaged, a spark may be generated in the damaged portion, resulting in disconnection. Then, not only the defect rate of the coil assembly is increased, but it is necessary to inspect whether the conducting wire is disconnected after the magnetizing step.

Therefore, in the magnetization process, magnetization is performed in a state where a resistor is connected between both ends of the electromagnetic coil. In this way, the voltage generated at both ends of the exciting coil is reduced, and it is difficult for sparks to occur in the damaged portion of the conductor.
Japanese Patent Application Laid-Open No. 10-125531

  However, such a resistor can reduce the voltage generated at both ends of the exciting coil, but cannot reliably prevent it. For this reason, there is a possibility that a spark may be generated in the damaged portion of the conductor. This also applies to not only the damaged part of the conductor, but also the part where the contact state is unstable in the electric circuit, for example, the contact part of the power supply brush and commutator in a rotating electric machine using a power supply brush and commutator. It is a possible problem as well.

  The present invention has been made in order to solve the above-described problems, and the purpose of the present invention is to generate an induced electromotive force in a coil under the influence of a magnetizing magnetic field for magnetizing a magnetic material. An object of the present invention is to provide a magnet magnetizing apparatus for a rotating electrical machine and a magnet magnetizing method for the rotating electrical machine that can reliably prevent a high voltage from being generated between both ends of a coil.

  In order to solve the above-described problems, the invention according to claim 1 is directed to a rotating electrical machine in which an armature coil and a magnetic material that becomes a magnet when magnetized are contained in a housing. A magnet magnetizing apparatus for a rotating electric machine that applies a magnetizing magnetic field to the magnetic body from the outside to change the magnetic body into the magnet, wherein the electric machine Capacitor connected between both ends of the child coil and charged with charge to suppress an increase in voltage across the armature coil based on an induced electromotive force generated in the armature coil under the influence of the magnetizing magnetic field The gist is that

  According to a second aspect of the present invention, in the magnet magnetizing apparatus for a rotating electric machine according to the first aspect, the rotating electric machine fixes the magnetic body that becomes a magnet by being magnetized in the housing. The housing has a power supply brush, and rotatably accommodates the armature provided with the armature coil and a commutator connected to the armature coil and in sliding contact with the power supply brush inside the magnetic body. The gist is that it is configured.

  According to a third aspect of the present invention, in the magnet magnetizing apparatus for a rotating electric machine according to the first or second aspect, a resistor is connected in parallel to the capacitor so as to discharge the electric charge charged by the capacitor. The gist of this is

  According to a fourth aspect of the present invention, in the magnet magnetizing apparatus for a rotating electric machine according to any one of the first to third aspects, the rotating electric machine is configured to supply power to the armature coil from the outside. A power supply connector is provided, which is connected to the power supply connector, and has a connection connector connected to the capacitor so that the capacitor is connected between both ends of the armature coil when the power supply connector is connected. The gist of this is

  The gist of a fifth aspect of the present invention is the magnet magnetizing apparatus for a rotating electric machine according to any one of the first to fourth aspects, wherein a plurality of the capacitors are connected in parallel. .

  According to a sixth aspect of the present invention, in the magnet magnetizing apparatus for a rotating electric machine according to the second aspect of the present invention, the capacitor has a voltage between the power supply brush and the commutator of 5 [V] or less. The gist is that the capacitor capacity is set.

  According to a seventh aspect of the present invention, for a rotating electrical machine in which an armature coil and a magnetic body that becomes a magnet when magnetized are housed in a housing, the magnetic body is magnetized from the outside of the housing. A magnet magnetizing method for a rotating electrical machine in which a magnetic field is applied and magnetized to change the magnetic body into the magnet, and a capacitor is inserted between both ends of the armature coil during the magnetizing. Connected and charged with the capacitor to suppress an increase in voltage across the armature coil based on the induced electromotive force generated in the armature coil under the influence of the magnetizing magnetic field This is the gist.

(Function)
According to the first and seventh aspects of the invention, when magnetizing, a capacitor is connected between both ends of the armature coil, and based on the induced electromotive force generated in the armature coil under the influence of the magnetizing magnetic field. The capacitor is charged with a capacitor so as to suppress an increase in the voltage across the armature coil. Thereby, since the electric charge from the armature coil by the induced electromotive force is instantaneously charged by the capacitor, it is reliably prevented that a high voltage is generated between both ends of the armature coil. Accordingly, a spark is generated in a portion where the coating of the conductive wire (winding) constituting the armature coil is damaged, or in a rotating electric machine using a power supply brush and a commutator where the contact is unstable in the electric circuit, for example, the power supply Sparks are reliably prevented from occurring at the contact portion of the brush and commutator.

  According to the second aspect of the present invention, the rotating electrical machine has a magnetic body and a power supply brush in the housing, and the armature coil and the armature coil are connected to the power supply brush in sliding contact with each other inside the magnetic body. An armature including a commutator is rotatably accommodated. In such a rotating electrical machine, the contact state is unstable when not in use such that the power supply brush and the commutator are magnetized. For this reason, sparks are generated between the power supply brush and the commutator during magnetization, and the power supply brush and the commutator are damaged, and in particular, if convex spark marks are generated on the brush sliding surface of the commutator, The roundness of the moving surface decreases. Then, when the power supply brush is in sliding contact (when the rotating electrical machine is rotating), generation of vibration and noise is induced, which causes a decrease in the quietness of the rotating electrical machine. Accordingly, it is possible to reliably prevent a high voltage from being generated between both ends of the armature coil by the capacitor, so that it is possible to improve the quietness that is an important factor for the rotating electric machine. That is, it is particularly effective for the rotating electric machine including the power supply brush and the commutator in this way.

  According to the invention described in claim 3, a resistor is connected in parallel to the capacitor, and the electric charge charged by the capacitor is discharged. Thereby, the capacitor can be discharged with a simple configuration.

  According to the fourth aspect of the present invention, the connection connector is connected to the capacitor so that the capacitor is connected between both ends of the armature coil when connected to the power supply connector provided in the rotating electric machine. . Thus, the capacitor can be easily connected between both ends of the armature coil simply by connecting the connection connector to the power supply connector.

  According to the invention described in claim 5, since a plurality of capacitors are connected in parallel, an inexpensive capacitor having a small capacitor capacity can be used, and one expensive capacitor having a large capacitor capacity can be used. The overall cost can be reduced rather than using.

  According to the invention described in claim 6, the capacitor capacity is set so that the voltage between the power supply brush and the commutator is 5 [V] or less. That is, since the spark does not occur when the voltage between the power supply brush and the commutator is 5 [V] or less, the occurrence of the spark can be surely prevented.

  According to the present invention, even if an induced electromotive force is generated in a coil under the influence of a magnetizing magnetic field for magnetizing a magnetic body, it is possible to reliably prevent a high voltage from being generated across the coil. A magnet magnetizing apparatus for a rotating electric machine and a magnet magnetizing method for the rotating electric machine can be provided.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, an embodiment of the invention will be described with reference to the drawings.

  FIG. 1 shows a DC motor 1 as a rotating electrical machine of the present embodiment. The DC motor 1 has a bottomed cylindrical yoke housing 2 as a housing. A pair of magnets (magnets) 3 are fixed to the inner surface of the yoke housing 2. The magnet 3 is a magnetic body 20 that is not magnetized during the assembly of the motor 1, and the magnetic body 20 is fixed to the yoke housing 2. Then, after the motor 1 is assembled, a magnetizing magnetic field is applied to the magnetic body 20 from the outside of the yoke housing 2 by the magnetizing device 21 described later shown in FIG. . An armature 4 is rotatably accommodated inside the magnet 3. The armature 4 includes a rotating shaft 5, a core 6 fixed to the rotating shaft 5, an armature coil 7 formed by winding a winding around the teeth of the core 6, and the rotating shaft 5. And a commutator 8 which is fixed and connected to the armature coil 7. The base end of the rotating shaft 5 is rotatably supported by a bearing 9 provided at the center of the bottom of the yoke housing 2.

  An end cap 10 is fixed to the opening of the yoke housing 2 with screws 11. A bearing 12 is provided at the center of the end cap 10, and the tip of the rotating shaft 5 is rotatably supported by the bearing 12. The distal end portion of the rotating shaft 5 protrudes from the end cap 10 to the outside, and is connected to the load so as to drive the load. A brush device 13 is fixed to the inner side surface of the end cap 10 with screws 14. The brush device 13 includes a pair of power supply brushes 15 that are in sliding contact with the commutator 8 and supply power. FIG. 1 is a cross-sectional view in which only one power supply brush 15 and one magnet 3 appear, and the power supply brush 15 and magnet 3 are arranged at positions facing each other with the rotating shaft 5 interposed therebetween as shown in FIG. Has been.

  A pair of power supply lines 16 are assembled to the end cap 10. One end of the power supply line 16 is connected to the power supply brush 15, and the other end has a power supply connector 17 (see FIG. 2). The power supply connector 17 has a pair of power supply terminals 17 a, and each power supply terminal 17 a is connected to a corresponding power supply brush 15. When power is supplied from the outside to the power supply brush 15 through the power supply connector 17 and the power supply line 16, power is supplied from the brush 15 to the armature 4 via the commutator 8, and the armature 4 rotates and rotates. The shaft 5 rotates.

  In the DC motor 1 having such a configuration, the magnetic body 20 that is not magnetized is fixed to the inner peripheral surface of the yoke housing 2, the armature 4 is accommodated inside the magnetic body 20, and the brush device 13 is fixed. The assembled end cap 10 is attached to the yoke housing 2 for assembly. Then, after the assembly, the magnetizing device 21 shown in FIG. 2 applies a magnetizing magnetic field to the magnetic body 20 from the outside of the DC motor 1 (yoke housing 2) to magnetize the magnet 3. .

  The magnetizing device 21 includes a magnetizing coil 22, a magnetizing power source 23, and a spark preventing device 24. The magnetizing coil 22 is provided so as to surround the motor 1 so as to be magnetized to the magnetic body 20 in the DC motor 1 (yoke housing 2), and receives power supply from a magnetizing power source 23. When power is supplied from a magnetizing power source 23, the magnetizing coil 22 applies a magnetizing magnetic field to the magnetic body 20 from the outside of the DC motor 1 (yoke housing 2) so as to change the magnetic body 20 to the magnet 3. Apply.

  Here, the contact state of the power supply brush 15 and the commutator 8 is unstable when not in use, such as when magnetized. Therefore, when a magnetizing magnetic field is applied to the magnetic body 20, an armature coil 7 induced electromotive force is generated, and a high voltage is generated between both ends of the coil 7, and measures are taken when this induced electromotive force is generated. Otherwise, a spark occurs between the power supply brush 15 and the commutator 8. Then, the power supply brush 15 and the commutator 8 are damaged by the spark, and particularly when a convex spark mark is generated on the brush sliding surface of the commutator 8, the roundness of the brush sliding surface of the commutator 8 is reduced. When the power supply brush 15 is in sliding contact (when the DC motor 1 is rotated), the generation of vibrations and noises is induced, which causes a decrease in the quietness of the motor 1. Even when the coating of the winding constituting the armature coil 7 is damaged, a spark may be generated in the damaged portion, resulting in disconnection. For this reason, the spark prevention device 24 prevents sparks that occur between the power supply brush 15 and the commutator 8 or at the damaged portion of the coating of the windings when magnetized.

  The spark prevention device 24 includes three capacitors 25, three resistors 26 and a connection connector 27. The connection connector 27 has connection terminals 27 a connected to the power supply connector 17 and connected to the power supply terminals 17 a of the connector 17. Between the connection terminals 27a, three capacitors 25 are connected in parallel to each other, and a resistor 26 is connected to each capacitor 25 in parallel. That is, when the connection connector 27 is connected to the power supply connector 17 and electrically connected, the capacitor 25 is connected between the power supply terminals 17 a of the power supply connector 17, that is, between both ends of the armature coil 7.

  The DC motor 1 is disposed in the magnetizing coil 22 and is supplied with power from the magnetizing power source 23 to the magnetizing coil 22 to magnetize the magnetic body 20 in the DC motor 1 (yoke housing 2). A magnetic field is applied. Then, the magnetic body 20 in the DC motor 1 is changed to the magnet 3. Further, when this magnetization is performed, the armature coil 7 is also affected by the magnetization magnetic field, so that an induced electromotive force is generated in the armature coil 7. Then, although the movement of the electric charge due to the induced electromotive force occurs, the electric charge is instantaneously charged by each capacitor 25, and the increase in the voltage across the armature coil 7 is reliably suppressed. That is, it is reliably prevented that a high voltage is generated between both ends of the armature coil 7. The electric charge charged in each capacitor 25 is quickly consumed via the resistor 26.

  3 shows that when the DC motor 1 is configured under predetermined conditions (dimensions, materials, etc.), the power supply brush 15 and the commutator with respect to the capacity of the capacitor 25 (the total capacity in the present embodiment having a plurality of capacitors 25). The relationship of the voltage which generate | occur | produces between 8 is shown. It has been experimentally known that no spark is generated between the power supply brush 15 and the commutator 8 when the voltage generated between the power supply brush 15 and the commutator 8 is 5 V or less. In the direct current motor 1, the total capacity of the three capacitors 25 is desirably 25000 [μF] or more. In addition, even if the voltage generated between the power supply brush 15 and the commutator 8 is 15 [V] or less, it has been experimentally known that almost no spark is generated between the power supply brush 15 and the commutator 8. The total capacity of the three capacitors 25 may be 10,000 [μF] or more. Thereby, the total capacity of the capacitor 25 of the present embodiment is set so that the voltage between the power supply brush 15 and the commutator 8 where no spark is generated is 5 [V] or less.

  This reliably suppresses an increase in the voltage across the armature coil 7 during magnetization, and reliably prevents a spark that may occur between the power supply brush 15 and the commutator 8. Further, since the rise in the voltage between both ends of the armature coil 7 is surely suppressed during magnetization, even if the coating of the winding constituting the armature coil 7 is damaged, it can occur in the damaged portion. Sparks are reliably prevented.

  Next, characteristic effects of the present embodiment will be described.

  (1) At the time of magnetization, a capacitor 25 is connected between both ends of the armature coil 7, and both ends of the armature coil 7 based on the induced electromotive force generated in the armature coil 7 under the influence of the magnetizing magnetic field. Charge is charged by the capacitor 25 in order to suppress an increase in inter-voltage. Thereby, since the electric charge from the armature coil 7 due to the induced electromotive force is instantaneously charged by the capacitor 25, it is possible to reliably prevent a high voltage from being generated between both ends of the armature coil 7. Therefore, a spark is generated in a portion where the coating of the conductive wire (winding) constituting the armature coil 7 is damaged, or the contact is unstable in the electric circuit, in this embodiment, the contact between the power supply brush 15 and the commutator 8. It is possible to reliably prevent a spark from occurring in the portion.

  Incidentally, in the DC motor 1 as in the present embodiment, the contact state is unstable when the power supply brush 15 and the commutator 8 are not used so as to be magnetized. Therefore, a spark is generated between the power supply brush 15 and the commutator 8 at the time of magnetization, and the power supply brush 15 and the commutator 8 are damaged. In particular, a convex spark mark is generated on the brush sliding surface of the commutator 8. The roundness of the brush sliding surface of the commutator 8 decreases. Then, when the power supply brush 15 is in sliding contact (when the motor 1 is rotating), generation of vibration and noise is induced, which causes a decrease in the quietness of the DC motor 1. Accordingly, it is possible to reliably prevent a high voltage from being generated across the armature coil 7 by the capacitor 25, so that it is possible to improve the quietness that is an important factor for the DC motor 1. That is, the DC motor 1 including the power supply brush 15 and the commutator 8 as described above is particularly effective.

  (2) A resistor 26 is connected to the capacitor 25 in parallel with the capacitor 25, and the charge charged by the capacitor 25 is discharged. Thereby, the capacitor 25 can be discharged with a simple configuration.

  (3) The connection connector 27 is connected to the capacitor 25 so that the capacitor 25 is connected between both ends of the armature coil 7 when connected to the power supply connector 17 provided in the DC motor 1. Thus, the capacitor 25 can be easily connected between both ends of the armature coil 7 simply by connecting the connection connector 27 to the power supply connector 17.

  (4) Since a plurality of capacitors 25 (three in the present embodiment) are connected in parallel, an inexpensive capacitor having a small capacitor capacity can be used, and one expensive capacitor having a large capacitor capacity can be used. The overall cost can be reduced compared to using a capacitor.

  (5) The capacitance of the capacitor 25 is set so that the voltage between the power supply brush 15 and the commutator 8 is 5 [V] or less. That is, since the spark does not occur when the voltage between the power supply brush 15 and the commutator 8 is 5 [V] or less, the occurrence of the spark can be surely prevented.

  In addition, you may change embodiment of this invention as follows.

  In the above embodiment, three capacitors 25 are used. However, one capacitor may be used or a plurality of capacitors may be used. Further, the connection of the capacitor 25 may be changed as appropriate. The total capacity of the capacitor 25 is set so that the voltage between the power supply brush 15 and the commutator 8 is 5 [V] or less, but the voltage between the power supply brush 15 and the commutator 8 is limited to this. Is not to be done. Further, the total capacity of the capacitor 25 may be set based on other criteria.

  In the above embodiment, three resistors 26 are used corresponding to the capacitor 25, but one resistor or a plurality of other resistors may be used. Further, the connection of the resistor 26 may be changed as appropriate. If the resistor 26 is not necessary, it may be omitted.

  In the above embodiment, the spark prevention device 24 is connected to the DC motor 1 using the connection connector 27, but the spark prevention device 24 is connected to the DC motor 1 using means other than the connection connector 27. You may make it connect.

  In the above embodiment, the magnet 3 (magnetic body 20) is a pair (two), but may be two or more.

  In the above embodiment, the power supply brush 15 is a pair (two), but may be two or more.

  In the above embodiment, the DC motor 1 as the rotating electric machine having the power supply brush 15 and the commutator 8 is used. However, the present invention is not limited to this. For example, the electric rotating machine having the power supply brush 15 and the commutator 8 is used. Or you may use the rotary electric machine with which an armature coil is provided in the rotor side.

Sectional drawing of the DC motor of this embodiment. The schematic block diagram of a magnetizing apparatus. The figure which shows the relationship of the voltage between a brush and a commutator with respect to a capacitor capacity.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... DC motor as a rotating electrical machine, 2 ... Yoke housing as a housing, 3 ... Magnet, 4 ... Armature, 7 ... Armature coil, 8 ... Commutator, 15 ... Feed brush, 17 ... Feed connector, 20 ... Magnetic Body, 25 ... capacitor, 26 ... resistor, 27 ... connection connector.

Claims (7)

Magnetization is performed by applying a magnetizing magnetic field to the magnetic body from the outside of the housing with respect to the rotating electrical machine in which the armature coil and the magnetic body that is magnetized by being magnetized are accommodated in the housing. A magnet magnetizing apparatus for a rotating electrical machine that changes the magnetic body to the magnet,
During the magnetization, the voltage across the armature coil is increased based on the induced electromotive force that is connected between both ends of the armature coil and is generated in the armature coil under the influence of the magnetizing magnetic field. A magnet magnetizing apparatus for a rotating electrical machine, comprising a capacitor for charging an electric charge so as to suppress electric current. The magnet magnetizing apparatus for a rotating electrical machine according to claim 1,
The rotating electrical machine fixes the magnetic body that becomes a magnet by being magnetized in the housing and has a power supply brush in the housing, and the armature coil and the electrical machine are disposed inside the magnetic body. A magnet magnetizing apparatus for a rotating electrical machine, comprising: an armature that is connected to a child coil and includes a commutator that is in sliding contact with the power supply brush. The magnet magnetizing apparatus for a rotating electrical machine according to claim 1 or 2,
A magnet magnetizing apparatus for a rotating electrical machine, wherein a resistor is connected to the capacitor in parallel with the capacitor so as to discharge the electric charge charged by the capacitor. In the magnet magnetization apparatus of the rotary electric machine of any one of Claims 1-3,
The rotating electrical machine is provided with a power feeding connector for supplying power to the armature coil from the outside,
A rotating electrical machine having a connection connector connected to the power supply connector and connected to the capacitor so that the capacitor is connected between both ends of the armature coil when the power supply connector is connected. Magnet magnetizer. In the magnet magnetization apparatus of the rotary electric machine of any one of Claims 1-4,
A magnet magnetizing apparatus for a rotating electrical machine, wherein a plurality of the capacitors are connected in parallel. The magnet magnetizing apparatus for a rotating electrical machine according to claim 2,
The magnet magnetizing apparatus for a rotating electrical machine, wherein the capacitor has a capacitor capacity set so that a voltage between the power supply brush and the commutator is 5 [V] or less. Magnetization is performed by applying a magnetizing magnetic field to the magnetic body from the outside of the housing with respect to the rotating electrical machine in which the armature coil and the magnetic body that is magnetized by being magnetized are accommodated in the housing. A magnet magnetizing method for a rotating electrical machine in which the magnetic body is changed to the magnet,
During the magnetization, a capacitor is connected between both ends of the armature coil, and a voltage across the armature coil based on an induced electromotive force generated in the armature coil under the influence of the magnetizing magnetic field. A magnet magnetizing method for a rotating electrical machine, wherein the capacitor is charged with electric charges so as to suppress the rise of the rotating electric machine.

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