JPS61280733A - Assembly of pulse motor - Google Patents

Abstract

PURPOSE:To obtain the maximum magnetic efficiency by a method wherein the variation of the magnetic flux in a magnetic path consisting of a permanent magnet and magnetic poles which constitute a pulse motor is measured and a phase difference between respective rotary magnetic poles is regulated in accordance with the measured flux. CONSTITUTION:If cores 5 and 6, an inside magnetic pole 2 and a permanent magnet 7 are settled and outside magnetic poles 3 and 4 are idled on a center shaft 8, the inside magnetic pole 2 and the outside magnetic poles 3 and 4 attract each other to rest at a magnetically stable position. By making this resting position a reference, the center shaft 8 is turned by an angle corresponding to a predetermined phase difference and settled. Then the other inside magnetic pole 1 is put on the cores 5 and 6, being able to rotate. If a flux is measured through coils 9 and 10 for exciting the inside magnetic pole 1 while the other inside magnetic pole 1 is being turned on the center shaft 8, the maximum flux is obtained at a magnetically stable position. Turning the inside magnetic pole 1 is discontinued at this position and the inside magnetic pole 1 is settled on the cores 5 and 6.

Description

[Detailed description of the invention] [Table of contents] - Overview - Industrial application field - Conventional technology - Problems that the invention solves or attempts to solve - Means and effects for solving the problems - Examples - Invention Effect [Summary] A plurality of rotating magnetic poles (inner magnetic poles) having a plurality of external teeth are mounted on the central axis within a cylindrical stator (outer magnetic poles) having a plurality of internal teeth with a predetermined phase difference. In this method, first, the core, the first rotating magnetic pole, and the permanent magnet are fixed on the central axis, and the stator is allowed to freely rotate, so that the relative position of the rotating magnetic pole and the stator is magnetically stabilized by the magnetic flux of the permanent magnet, and the relative position of the rotating magnetic pole and the stator is brought to a stationary position. is set as the reference position. The central shaft is rotated from this reference position by an angle corresponding to a predetermined phase difference to fix the central shaft to the stator. Next, a second rotating magnetic pole is attached to the core on the central axis, and the second rotating magnetic pole is rotated relative to the core while measuring the flux meter connected to the excitation coil of this rotating magnetic pole, so that the magnetic flux is maximized. At this position, the second rotating magnetic pole is fixed relative to the central axis. This leads to the first. The second rotating magnetic poles are fixed in phase-shifted positions where maximum magnetic efficiency can be obtained, regardless of variations such as manufacturing accuracy errors.

[Industrial application field]

The present invention relates to a method for assembling a pulse motor using permanent magnets, and in particular to a method of assembling a pulse motor using permanent magnets, and particularly to a method of assembling a pulse motor using a permanent magnet, and in particular, when a plurality of rotating magnetic poles having a plurality of external teeth are fixed on a central axis with a predetermined phase difference.
! This invention relates to a method for positioning and fixing an L-shaft.

[Conventional technology]

A pulse motor using a permanent magnet has a plurality of rotating magnetic poles each having a plurality of external teeth fixed together with a permanent magnet on a central axis within a cylindrical stator having a plurality of internal teeth, and a gap between two adjacent rotating magnetic poles. The rotating magnetic poles are arranged with a pitch shifted by a predetermined phase from each other. In such a pulse motor, each coil is energized in turn, each rotating magnetic pole is energized in turn according to the direction of the current and the order of the coils, and the outer teeth of the excited rotating magnetic poles are made to face the inner teeth of the stator. By doing so, each rotating magnetic pole is sequentially moved to rotate the central shaft (rotor).

Conventionally, in order to fix a plurality of rotating magnetic poles on the central axis with their respective phases shifted, key grooves are formed in each rotating magnetic pole with positions shifted corresponding to a predetermined phase difference, and these key grooves are fixed on the central axis with their respective phases shifted. The rotating magnetic pole was fixed to the central axis by attaching it to a common key.

[Problem that the invention seeks to solve]

In the conventional assembly method of fixing the rotating magnetic pole on the central axis by shifting the phase using a keyway, the accuracy of the phase difference decreases due to manufacturing errors in the keyway or assembly errors when press-fitting the keyway, resulting in variations in the phase difference. may occur, making it impossible to obtain a pulse motor with predetermined characteristics.Also, due to variations in the pitch of the internal teeth of the stator and the external teeth of the rotating magnetic poles, it may not be possible to obtain the maximum magnetic efficiency at the position of the set phase difference. In some cases, this may result in a decrease in motor drive efficiency.

The present invention solves the above-mentioned drawbacks of the prior art, and makes it possible to obtain the maximum magnetic efficiency regardless of manufacturing errors in parts such as the stator and rotating magnetic poles, and variations in the pitch of internal teeth and external teeth. The object of the present invention is to provide a method for assembling a pulse motor that fixes each rotating magnetic pole with a phase difference. - [Means for solving the problem] In order to achieve this object, the present invention fixes a sleeve-shaped core on the central axis, and on the core, there are provided a plurality of external teeth having a plurality of external teeth on the circumference. The inner magnetic poles of the inner magnetic poles are installed in parallel, and a coil is provided between two adjacent inner magnetic poles, and the number of outer teeth of each inner magnetic pole is the same, and each outer tooth has a predetermined phase difference from each other. A cylindrical outer magnetic pole having a plurality of inner teeth arranged at staggered pitches and facing the outer teeth of each inner magnetic pole is provided on the outer periphery of the inner magnetic pole coaxially with the central axis, and the inner magnetic pole is connected to the outer magnetic pole. In a method for assembling a pulse motor having a permanent magnet configured to be rotatable relative to the inner magnetic pole and a permanent magnet for forming a magnetic path passing through the inner magnetic pole and the outer magnetic pole, and a permanent magnet is fixed and the outer magnetic pole is rotatably mounted so that the magnetic flux of the permanent magnet forms a magnetic path passing through the core, the first inner magnetic pole and the outer magnetic pole, and the first inner magnetic pole and the outer magnetic pole mutually (b) rotating the central shaft by an angle corresponding to a predetermined phase difference from the magnetically stable position, and in this position, the central shaft is aligned with the outer magnetic pole; (C) rotatably mounting a second inner magnetic pole on the core, and providing means for measuring magnetic flux passing through the core; A method for assembling a pulse motor is provided, which includes the steps of: rotating the second inner magnetic pole to a position where the magnetic flux detected by the measuring means is maximum, and fixing the second inner magnetic pole to the core at this position.

[For production]

Core on central axis and one inner magnetic pole (or inner magnetic pole set)
If the permanent magnet is fixed and the outer magnetic pole is freely rotated, the inner magnetic pole and the outer magnetic pole will attract each other and will be in a magnetically stable position (the outer teeth of the inner magnetic pole and the inner teeth of the outer magnetic pole are facing each other). position). With this stationary position as a reference, the central shaft is rotated from this reference position by an angle corresponding to a predetermined phase difference, and the central shaft is fixed to the outer magnetic pole at this position. Next, another inner magnetic pole (or inner magnetic pole set)
is rotatably mounted on the core, the magnetic flux is measured through a coil etc. for exciting this inner magnetic pole, and when this other inner magnetic pole is rotated on the central axis, a magnetically stable position (between the outer teeth of the inner magnetic pole and The magnetic flux is maximum at the position where the outer magnetic pole faces the inner teeth. Rotation is stopped at the position where this magnetic flux is maximum, and the inner magnetic pole is fixed to the core at this position.

〔Example〕

FIG. 2 is a block diagram of a pulse motor to which the present invention is applied. A cylindrical sleeve-shaped core 5.6 and a permanent magnet 7 are fixed on the central axis s, and four rotating magnetic poles 1.6 are mounted on the core 5.6.
2.3.4 is fixed. As shown in FIG. 4, each rotating magnetic pole 1.2, 3.4 is a gear-shaped component having a predetermined number of external teeth 30, which are tooth-shaped magnetic poles, at a constant pitch on the circumference.

Coils 9 and 10 held by coil holders 36 are disposed between the rotating magnetic poles 1.2 and 3.4, respectively. A cylindrical stator 23 is provided on the outer periphery of the rotating magnetic poles 1, 2, 3.4 coaxially with the central axis 8. On the inner surface of the stator 23, as shown in FIG.
．． The same number of internal teeth 32 as the four external teeth 3o are formed. The stator 23 is provided with a slit (not shown), through which the end of the coil holder 36 protrudes outside the stator, and the coil stopper 11 locks the end of the coil holder 36 so that the coils 9, 1
゜ is fixed and held within the stator. Further, the winding ends of the coils 9 and 10 are led out to the outside through this slit.

The entire motor is covered with a front cover 12 and a rear cover 13. 14 is a washer, and 15 is a bearing such as a pole bearing.

The arrangement relationship of the rotating magnetic poles 1.2 and 3.4 is shown in FIG. Rotating magnetic poles 1, 2, 3.4 have phases of 0° and 180° respectively.
The outer teeth 30 of the rotating magnetic pole 1 are arranged to be shifted by 90°, 270°, and the outer teeth 30 of the rotating magnetic pole 1 are aligned with the stator 23
If the position is opposite to the inner teeth 32 of the stator, the remaining three rotating magnetic poles 2.3.4 will have their outer teeth 30 facing the stator, as shown in FIGS. It is fixed at a position shifted by 1/2 pitch, 1/4 pinch, and 3/4 pitch with respect to the internal teeth 32 of 23. That is, the left pair of rotating magnetic poles 1.2 are out of phase by 1/2 pitch (180°),
Similarly, the rotating magnetic poles 1 & Il on the right side are also out of phase by 1/2 pitch (180°), and each rotating magnetic pole group 1° 2 and 3,
4 are arranged with their phases shifted by 1/4 pitch (90°). Note that if the winding direction of the coils 9 and 10 and the current direction are appropriately selected, the order of the phase difference will be the same as the above-mentioned O''.
, 180°, 90°, 270° instead of 0°, 180°
A pulse motor can also be configured with angles of 270°, 90°, and 90°.

A method of assembling the rotating magnetic poles 1, 2, 3.4 arranged in this manner will be explained with reference to FIGS. 1 and 6.

First, only one rotating magnetic pole 2 is fixed to the core 5, and this is fixed to the central shaft 8 together with a permanent magnet 7 magnetized in the axial direction.

A yoke 17 is further rotatably mounted on the central shaft 8 via a bearing 15. A stator 16 is fixed to the yoke 17. The central shaft 8 is connected to a DC motor 24 via a coupling 19, and an encoder 18 is attached to the DC motor 24. The encoder 18 has a counter 20
and a counter display 35 are connected. permanent magnet 7
The magnetic flux generated from the core 5, rotating magnetic pole 2, stator 1
6. Form a magnetic path passing through the yoke 17 and returning to the permanent magnet 7. At this time, since the stator 16 is rotatable with respect to the rotating magnetic pole 2, the external teeth of the rotating magnetic pole 2 and the internal teeth of the stator 16 attract each other, and the rotating magnetic pole 2 and the stator 16 are in a magnetically stable position, that is. The rotating magnetic pole 2 comes to rest at a position where the outer teeth and the inner teeth of the stator 16 face each other. The counter 20 of the encoder 18 is reset in this magnetically stable position. From this state, drive the DC motor 24 to
The central shaft 8 is rotated relative to the stator 16 by an angle (determined by the number of teeth) corresponding to the pift. As a result, the internal teeth of the stator 16 and the external teeth of the rotating magnetic pole 2 are shifted by 1/2 bift.

The amount of rotation of the DC motor 24 is detected by a counter 20 attached to the encoder 18, and a control circuit (not related) is configured so that the DC motor 24 is stopped by the output of the counter 20 when it rotates by the predetermined angle. In this state, the stator 16 is fixed to the central shaft 8 and cannot rotate.

Next, a coil 9 is installed, and another rotating magnetic pole 1 is rotatably installed on the core 5. A magnetometer 21 is connected to the lead wire of the winding of the coil 9. In this state, the rotating magnetic pole 1 is manually rotated about the central axis 8 and the magnetic flux change detected by the magnetometer is observed. The rotation is stopped at the opposing position, and the rotating magnetic pole 1 is fixed on the core 5 at this position. still,
For example, in Figure 1, the magnetic flux is maximum on the left side of the magnet.
This is a case where the right side is the S pole and the winding direction of the coil is clockwise when viewed from the right side of the motor. As a result, the pair of rotating magnetic poles 1.2 are fixedly arranged on the core fixed to the central shaft 8, with the outer teeth being shifted by 1/2 pitch from each other.

Similarly, another set of rotating magnetic poles 3.4 is fixed on the core 6 with the outer teeth offset by 1/2 pitch from each other.

A method of fixing two sets of rotating magnetic poles 1, 2 and 3°4, which have a phase difference of 1/2 pitch in this manner, are shifted by 174 pitches and fixed on a common central axis will be explained using Fig. 6. do. First, a pair of rotating magnetic poles 1.2 on the core 5 are fixed on the central shaft 8 together with the permanent magnet 7. Further, the yoke 17 and the stator 16 are rotatably attached to the central shaft 8. A DC motor 24 and an encoder 18 are connected to the central shaft 8 via a compling ring 19 as in the case of FIG.
, counter 20 and display 35 are connected. By making the stator 16 rotatable with respect to the rotating magnetic poles 1.2 in this way, a magnetically stable position is established where the magnetic flux change in the magnetic path passing through the core 5 formed by the magnetic flux of the permanent magnet 7 is minimized.
That is, the stator 16 comes to rest at a position where the outer teeth of the rotating magnetic poles 2 and the inner teeth of the stator 16 face each other. At this position, the counter 20 is reset, and with the stator 16 fixed, the DC motor 24 is driven to rotate the central shaft 8 by an angle opposite to a predetermined phase difference (1/4 pitch). As a result, the internal teeth of the stator 16 and the external teeth of the rotating magnetic pole 2 are shifted by 1/4 pitch. The DC motor 24 has a counter 2 that detects the rotation of the encoder 18, as in the case of FIG.
0 detects a rotation amount of a predetermined angle, the drive is controlled by stopping the DC motor 24 via a control circuit (not shown). In this state, the stator 16 is fixed to the central shaft 8. Next, another set of rotating magnetic poles 3 and 4 fixed on the core 6 is rotatably mounted on the central shaft 8. Rotating magnetic pole 3
．． A magnetometer 22 is connected to the coil 1° between the two. While observing the magnetic flux meter 22, the rotating magnetic pole 3.4 is manually rotated together with the core 6, and the position where the change in the magnetic flux flowing through the core 6 is minimal, that is, the outer teeth of the rotating magnetic pole 3 and the inner teeth of the stator 16 are opposed to each other. The core 6 is fixed to the central axis 8 at this position. As a result, the two sets of rotating magnetic poles are fixed with a phase difference of 1/4 pitch, and the phases of the four rotating magnetic poles 1.2 and 3.4 are sequentially O'' and 180°.

It is fixed on the central axis 8 so that the angles are 90' and 270°. From this state, by rotatably attaching another yoke to the end of the central shaft 8 on the rotating magnetic pole 4 side and removing the magnetometer, a pulse motor can be constructed.

Note that the configuration shown in FIG. 1 consists of one set of rotating magnetic poles 1.2 or 3,
Although it was used exclusively as a phase adjustment means for assembling two rotating magnetic poles (1, 2 and 3° 4), when adjusting the phase of one of the two sets of rotating magnetic poles (1, 2 and 3°4), the parts of the motor actually used ( (center shaft, yoke, stator, etc.) by the method shown in Figure 1, and then attach another rotating magnetic pole whose phase has been adjusted by the method shown in Figure 1 to this central shaft, and then The method also allows for phase adjustment between the rotating magnetic pole assemblies.

Further, in the above description based on FIGS. 1 and 6, the DC motor 24 may be omitted and the central shaft 8 may be manually rotated by a predetermined angle while observing the display 35 of the counter 20.

Although the above embodiment is an inner rotor type motor in which the stator is on the outside and the rotor is on the inside, the present invention can be similarly applied to an outer rotor type motor.

〔Effect of the invention〕

As explained above, in the method for assembling a pulse motor according to the present invention, changes in the magnetic flux of the magnetic path formed by the magnetic flux of the permanent magnets constituting the pulse motor are measured, and based on this, the position between each rotating magnetic pole is To adjust the phase difference, the maximum magnetic efficiency is always achieved when the central shaft is rotated by a predetermined amount of rotation, regardless of variations in pitch, shape, etc. due to manufacturing errors in the outer teeth of each rotating magnetic pole and the inner teeth of the stator. Each rotating magnetic pole can be fixed in the position where it should be, improving motor characteristics and driving the motor with maximum efficiency.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a mechanism for carrying out the method of the present invention, FIG. 2 is a block diagram of an example of a pulse motor to which the present invention is applied, FIG. 3 is a sectional view of the stator of the pulse motor shown in FIG. The figure is a front view of the rotating magnetic pole of the pulse motor in Figure 2, and Figure 5 is a front view of the rotating magnetic pole of the pulse motor in Figure 2.
FIG. 6 is an explanatory diagram of the phase difference between rotating magnetic poles of the pulse motor shown in the figure, and FIG. 6 is a configuration diagram of a mechanism for implementing the method of the present invention. 2--First rotating magnetic pole, 1--Second rotating magnetic pole, 3
...-third rotating magnetic pole, 4--fourth rotating magnetic pole, 5.
6--core, 7-permanent magnet, 8-central axis,
9.10-coil, 16...-stator,
17-Coke, 18-Encoder, 20--Counter, 21.22--Magnetometer, 30--External tooth, 3
2...-Internal teeth. Explanatory diagram of the implementation mechanism of the method of the present invention Fig. 1 12.3.4...Rotating magnetic pole 5.6-9
．． Core 7... Permanent magnet 8... Central axis 9jO... Coil 16... Stator 17... Yoke 1800.
Engineering: /,, -ta・19...Coupling 2
o... Counter 21.22... Magnetometer
24...DC motor 35...Indicator Block diagram of a pulse motor to which the present invention is applied Fig. 2 1.2, 3.4... Rotating magnetic poles 5, 6...
・Core 7...Permanent magnet 8...Central axis 9.10...Coil 11...Coil stopper 12...Front cover 13...Rear cover 14...Washer 15...Bearing 2
3... Stator 36... Cross-sectional view of coil holder stator Front view of rotating magnetic pole No. 3
Figure 4 Figure 23...Stator i, 2.3, 4°
°゛Rotation Pole 32...Inner tooth 3
0...External teeth (c)
(d) Illustration of rotating magnetic pole arrangement Figure 5

Claims (2)

[Claims] (1) A sleeve-shaped core is fixed on the central axis, and on the core, a plurality of inner magnetic poles having a plurality of external teeth are mounted in parallel on the circumference, and between two adjacent inner magnetic poles, An excitation coil is provided, the number of external teeth of each inner magnetic pole is the same, and the pitches are shifted so that each outer tooth has a predetermined phase difference from each other, and a plurality of excitation coils facing the outer teeth of each inner magnetic pole are arranged. A cylindrical outer magnetic pole having internal teeth is provided on the outer periphery of the inner magnetic pole coaxially with the central axis, the inner magnetic pole is configured to be rotatable relative to the outer magnetic pole, and the inner magnetic pole and the outer magnetic pole are configured to be rotatable relative to the outer magnetic pole. In a method for assembling a pulse motor having a permanent magnet for forming a magnetic path passing through, (a) a core, a first inner magnetic pole, and a permanent magnet are fixed on a central axis, and an outer magnetic pole is rotatably attached to the permanent magnet. forming a magnetic path passing through the core, the first inner magnetic pole, and the outer magnetic pole by the magnetic flux of the magnet, and the first inner magnetic pole and the outer magnetic pole mutually attract each other to a stationary magnetically stable position; b) rotating the central shaft by an angle corresponding to a predetermined phase difference from the magnetically stable position, and non-rotatably fixing the central shaft to the outer magnetic pole at this position; A magnetic pole is rotatably mounted on the core, and a magnetic flux measuring means passing through the core is provided, and the second inner magnetic pole is rotated with respect to the core to a position where the magnetic flux detected by the magnetic flux measuring means is maximum. fixing the second inner magnetic pole to the core at a position. (2) The magnetic flux measuring means measures the magnetic flux based on the output of the excitation coil.
1) Assembly method of the pulse motor described in section 1).