JP3306356B2 - DC motor magnetization method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for magnetizing a DC motor used in a hermetic compressor having a rare earth magnet such as a ferrite magnet or a neodymium magnet.

[0002]

2. Description of the Related Art DC motors used in hermetic compressors (compressors) and the like are required to have a required output with a size as small as possible. For this purpose, ferrite magnets are usually used as magnets for the rotor, but recently neodymium, ferrite,
Neodymium magnets, which are rare earth magnets made of iron and boron, are also used. Neodymium magnets are more expensive per unit weight than ordinary ferrite magnets, but their BH product has a significant advantage.

However, a ferrite magnet or a neodymium magnet is inserted into a laminated core and then magnetized by passing an electric current through a stator (stator) winding.
Since a current of 00 A is instantaneously supplied, the stator winding may be greatly distorted or deformed by the acting force acting between the windings, and the coil may come into contact with the compressor unit (pump). In order to prevent this, the position of the DC motor and the position of the pump must be determined by assuming the amount of deformation of the stator winding in advance. As a result, compressor cases tended to be large.

Normally, a DC motor for a compressor used in an air conditioner has an impedance of 2Ω (60 Hz).
When the magnetizing machine uses a capacitor with a capacity of about 2500 μF, the magnetizing voltage is relatively low, the magnetizing time is lengthened, and the capacitor is charged and discharged to magnetize. The magnetizing method has a certain effect because the amount of deformation of the stator winding can be reduced.

However, a DC motor for a compressor used in a refrigerator or the like having a large number of motor windings has a high impedance of about 10Ω (at 60 Hz). Therefore, a necessary current is obtained unless a high voltage is applied during magnetization. I can't. Therefore, if the magnetizing time is increased by increasing the voltage, the stress on the coil is increased, the deformation of the stator winding is increased, and the coil may come into contact with the pump. Further, since the amount of deformation of the stator winding also varies from case to case, the assumption of the amount of deformation is not fixed in advance, and the assembly work of the compressor is complicated.

[0006]

SUMMARY OF THE INVENTION Accordingly, the present invention has been made in view of the above problems, and reduces the deformation of the coil of the stator winding by appropriately selecting the magnetizing conditions at the time of magnetizing the rare earth magnet. DC motor to facilitate the assembly work of the compressor, and to provide a deformation corresponding to the deformation occurring when the coil is magnetized in advance, and to facilitate the compressor assembly work by incorporating the deformed coil. Provide a way.

[0007]

To achieve the above object, a DC motor magnetizing method according to claim 1 of the present invention comprises:
A stator in which a stator winding is wound around a laminated core, and a rotor having a magnetized member inserted therein, and a DC motor is formed by incorporating the rotor into the stator, and the stator winding is energized to form a DC motor. A method of magnetizing a DC motor for magnetizing a magnetized member of a rotor, wherein a capacitor capacity is reduced.
500 μF or less, and the charging voltage of the capacitor is 200 to
At 3000 V, a capacitor charged with an electric charge necessary for magnetizing the magnetized member of the rotor was connected to the stator winding to energize, and the energizing time was set within 10 ms.

Thus, in a DC motor used in a compressor or the like having a high impedance used in a refrigerator having a large number of turns of the motor winding, deformation of the stator winding can be reduced by properly selecting the magnetizing conditions of the rare earth magnet of the rotor. Reduce the size to facilitate compressor assembly work.

According to a second aspect of the present invention, there is provided a method of magnetizing a DC motor, comprising: a stator having a stator core wound around a laminated core; and a rotor having a member to be magnetized inserted therein.
In addition to incorporating the rotor into the stator,
To magnetize the magnetized member of the rotor to produce a DC motor.
A method of magnetizing a DC motor , comprising forming and charging a capacitor charged with an electric charge necessary for magnetizing the magnetized member of the rotor to the stator winding and energizing the energizing time within 10 ms . The rotor is attached to the stator.
Before magnetizing the magnetized member of the rotor before assembling
The capacitor charged with the electric charge necessary for
After connecting and energizing, after incorporating the rotor, again
It was configured to energize.

In this way, the rotor ferrite magnet and rare earth
The deformation that occurs in the stator winding when the similar magnet is magnetized
Before assembly into the stator winding
After incorporating the DC motor into the DC motor,
This facilitates the work of assembling the compressor.

According to a third aspect of the present invention, there is provided a method of magnetizing a DC motor , comprising the steps of:
The charge required to magnetize the magnetized member is
The stator winding is selected by selecting the capacity of the capacitor.
It was configured to adjust the power supply time to the power supply.

Thus, a refrigerator having a large number of motor windings
For high impedance compressors, etc.
In the DC motor used, the rare-earth magnet of the rotor
By properly selecting the magnetizing conditions, the stator winding
Reduce the size to facilitate compressor assembly work.

According to a fourth aspect of the present invention, in the method of magnetizing a DC motor, the stator winding has three phases and two of the three phases are used.
The phase stator winding was configured to be energized.

Thus, a refrigerator having a large number of motor windings
For high impedance compressors, etc.
In the DC motor used, the rare-earth magnet of the rotor
As the magnetizing conditions, select the capacity of the magnetizer capacitor properly.
The time required to energize the stator windings
Adjustable magnetization can minimize stator winding deformation
To facilitate the assembly work of the compressor.

[0015]

Embodiments of the present invention will be described below. An example of a normal magnetized DC motor for a compressor is shown in FIG. FIG. 1A is a cross-sectional view of a DC motor for a compressor in which a DC motor housed in a case and whose illustration of a rotor is omitted is coupled via a cup fixed to the compressor. FIG. 1B is a bottom cross-sectional view of the DC motor for a compressor in FIG. 1A, showing a cross section from the position of the cup.

In FIG. 1, 1 is a stator core of a DC motor, 2 is a stator winding, 3 is a coil end of the stator winding, 4 is a rotor shaft, 5 is a cup fixed to a compressor, and 6 is a compressor (not shown). Reference numeral 7 denotes a case in which a DC motor for a compressor is housed. A clearance (gap) exists between the coil end 3 of the stator winding and the cup 5. Also, as shown in FIG. 3B, the stator winding 2 has an A-phase, a B-phase, and a C-phase.
It consists of three-phase windings.

FIG. 2A is a sectional view of the stator, which comprises a stator core 1 and a slot 1a on which a winding is wound. The stator in this example has a total of 24 slots, around which A-phase, B-phase, and C-phase coils are wound. FIG. 2B is a winding connection diagram of the stator winding 2. Each phase coil is composed of an L coil and an M coil. The solid line indicates the L coil, and the broken line indicates the M coil. L
The coil is further obtained by connecting an L1 coil and an L2 coil in series, and the M coil is obtained by connecting an M1 coil and an M2 coil in series. The L coil and the M coil are connected in parallel.

For example, in the A phase, an L1 coil wound n times around the slots 22 and 15 and an L2 coil wound n times around the slots 21 and 16 are connected in series to form an L coil. An M coil is formed by connecting an M1 coil wound n times around 10 and a slot 3 and an M2 coil wound n times around a slot 9 and a slot 4 in series.

The number of turns n of the coil depends on the load.
For example, for a small compressor motor used in a refrigerator or the like, 120 to 150 times is appropriate. When the L coil and the M coil are connected in series, the number of turns may be half, and 60 to 75 times is appropriate.

First, in FIG. 1, if an arbitrary two-phase winding of the stator winding 2, for example, an A-phase and a B-phase is selected as the magnetizing coil, the rotor magnet is formed by the combined magnetic flux when the two-phase winding is energized. The magnetized position of (1) is as shown in the figure, and the coil end of the stator winding is greatly deformed under the strong influence of the metal of the cup 5 at the time of magnetizing.

In particular, in a DC motor for a compressor used in a refrigerator or the like having a large number of motor windings, a necessary current cannot be obtained unless a high voltage is applied during magnetization since the impedance is high. Therefore, if the magnetizing time is increased at a high voltage, the stress on the coil increases, the deformation of the stator winding increases, and the coil comes into contact with the compressor. Therefore, as a result of repeated experiments to solve the inconvenience, the following optimal conditions were found.

That is, conditions to be considered when magnetizing include the magnetizing time, the capacitor capacity of the magnetizer, the applied voltage, the material of the magnet, and the specifications of the motor. In the case of a DC motor having a large number of turns of a motor winding and a high impedance, the magnet is made of a rare-earth magnet and the rotor is magnetized.
It has been found that the optimal magnetization which can minimize the deformation of the stator winding can be achieved when the magnetization time is within 10 ms and the capacitor capacity of the magnetizer is 400 to 500 μF or less.

FIG. 3 is a drawing of the rotor. As shown in FIG. 3A, the rotor 8 is provided with four slots 10 and four rare earth magnets are inserted therein. The magnet material is commercially available NEOMAX-28UH (manufactured by Sumitomo Special Metals Co., Ltd.)
You are using The approximate values of the composition components of this magnet material are shown in Table 1.
Table 2 shows the magnetic properties (base material).

[0024]

[Table 1]

[0025]

[Table 2]

The length of the rare earth magnet is 20 to 32.5 m
m is appropriate, and can be very short as compared with ferrite. FIG. 4 shows an assembly drawing of the rotor 8, and end members 13 and 14, which also serve as balancers, are provided above and below the rotor 8 (shown on the left and right in the figure). The rotor core is swaged by clamping the rotor core so that the end faces 13 and 14 sandwich a flat plate between the end faces.
1 is assembled by caulking.

FIG. 5 is a wiring diagram of the magnetizing machine 16 and the magnetizing machine.
Connected to the motor lead 17. Magnetizer 16 is 200V
It is driven by an AC power supply and has a built-in capacitor. The capacitance of the capacitor can be set in the range of 100 to 3000 μF, and the charging voltage of the capacitor can be set in the range of 200 to 3000 V. Thus, the magnetizing time and the magnetizing peak time are adjusted according to the impedance of the motor, so that the magnet of the rotor 8 can be magnetized properly.

In a small refrigerator motor having a relatively high impedance, the impedance is about 10Ω.
(At 60 Hz). At this time, when magnetizing with 400 J of charge, the relationship of the time is shown in Table 3. In order to keep the magnetization time within 10 ms, the capacitance of the magnetization capacitor may be set to 500 μF or less. For example, FIG. 7 shows the relationship between the magnetization time and the current in the case of 500 μF or less.

[0029]

[Table 3]

The capacitor capacity of the magnetizer is set to 400 to 500.
When the charge at the time of magnetization is Q, the capacitance of the capacitor is C, and the voltage is V, the charge Q required for the magnetization is substantially constant, so that Q = １ ／ · CV ² Since the voltage V can be kept high by reducing the capacitance C of the capacitor, the impedance is high and it is necessary to apply a high voltage during magnetization. Magnetization of the DC motor used is properly performed.

Thus, in a compressor DC motor having a large number of turns and a high impedance used in a refrigerator or the like, deformation of the stator winding is reduced by appropriately selecting the magnetizing conditions of the rare earth magnet of the rotor. To facilitate the assembly work of the compressor.

Further, in order to reduce the influence of the deformation of the stator winding upon magnetization after the DC motor has been incorporated in the compressor, another method of magnetizing the stator winding before the DC winding is incorporated into the DC motor is as follows. A dummy rotor dedicated to magnetization is prepared in advance, the rotor and the stator winding are assembled, and a magnetizing voltage is applied once to the stator winding to cause deformation of the stator winding, which is then incorporated into the compressor. Correct the deformation assuming the state after that. Next, a DC motor having the stator winding mounted together with a non-magnetized rotor is assembled in a compressor, and a magnetizing voltage is applied again to magnetize.

As a result, the stator winding is greatly deformed by the first application of the magnetizing voltage, and the deformation of the stator winding by the second application of the magnetizing voltage is reduced. When the DC motor mounted together with the unmagnetized rotor is assembled in the compressor, the magnetizer does not need to be modified and the compressor assembling operation can be facilitated.

[0034]

As described above, the method of magnetizing a DC motor according to the present invention can be applied to a DC motor used for a refrigerator having a large number of turns of a motor winding and a high impedance, which is used for a refrigerator or the like. By appropriately selecting the magnetizing conditions of the magnet, the deformation of the stator winding can be reduced and the assembling work of the compressor is facilitated.

In addition, a large deformation which occurs in the stator winding when the ferrite magnet or the rare earth magnet of the rotor is magnetized is given before the DC motor is assembled, and the stator winding in which the deformation is corrected is provided together with the unmagnetized rotor. By incorporating it into a DC motor and then performing substantial magnetization, the deformation of the stator winding during substantial magnetization can be reduced,
Facilitates compressor assembly work.

[Brief description of the drawings]

FIG. 1 is a layout diagram of a DC motor to which a magnetization method according to the present invention is applied.

FIG. 2 is a sectional view and a winding connection diagram of a stator of a DC motor.

FIG. 3 is a sectional view of a rotor of a DC motor.

FIG. 4 is an assembly view of the rotor of the DC motor of the present invention.

FIG. 5 is a wiring diagram at the time of magnetizing and a magnetizing machine.

FIG. 6 is a diagram illustrating a relationship between a magnetization time and a current.

[Description of Signs] 1 Stator core 2 Stator winding 3 Coil end 4 Rotor shaft 5 Cup 6 Fixed partition 7 Storage case 8 Rotor 9 Rotor magnetic pole 10 Magnet insertion slot 11 Caulking member insertion slot 12 Plate magnet 13, 14 End face member 15 Rotor Plate plate 16 Magnetizer 17 Motor lead wire

────────────────────────────────────────────────── ─── Continued on the front page (72) Yoshihiko Nagase 2-5-5 Keihanhondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd. (56) References JP-A-9-168260 (JP, A) JP-A-9-168260 63-157646 (JP, A) WO 92/74009 (WO, A1) (58) Fields investigated (Int. Cl. ⁷ , DB name) H02K 15/03 H02K 21/14 H01F 13/00 H02K 29 / 00

Claims (4)

(57) [Claims] 1. A stator comprising a stator in which a stator winding is wound around a laminated core, and a rotor in which a member to be magnetized is inserted. A DC motor is formed by incorporating the rotor into the stator. And a magnetizing method for a DC motor that magnetizes the magnetized member of the rotor by energizing the capacitor.
An electric voltage of 200 to 3000 V, a capacitor charged with an electric charge necessary for magnetizing the magnetized member of the rotor is connected to the stator winding and energized, and the energizing time is set to 10 ms or less. Characteristic DC motor magnetization method. 2. A stator comprising: a stator having a stator core wound on a laminated core; and a rotor having a member to be magnetized inserted therein.
Incorporating the rotor into the
To magnetize the magnetized member of the rotor,
A method of magnetizing a DC motor, wherein a capacitor charged with an electric charge necessary for magnetizing a member to be magnetized of the rotor is connected to the stator winding and energized, and the energizing time is within 10 ms. in, before incorporating the rotor to the stator, the rotor
The core charged with the electric charge necessary to magnetize the
A capacitor connected to the stator winding and energized,
After installing the rotor, it is energized again.
DC motor magnetization method. 3. The impedance of the stator winding,
For the electric charge required to magnetize the magnetized member,
3. The magnetizing method for a DC motor according to claim 2, wherein an energizing time to the stator winding is adjusted by selecting a capacity of the capacitor. 4. The method according to claim 1, wherein the stator winding has three phases, and two-phase stator windings are energized.