JPS60180471A - Multipolar dc motor - Google Patents

Abstract

PURPOSE:To facilitate the assembling of a motor by concentrically winding an armature coil, and using a permanent magnet used as a rotor also for a generating magnet for detecting the rotating speed of the rotor, thereby simplifying the construction. CONSTITUTION:An armature 10 has a coil 12 concentrically wound on a bobbin 11, and a core 13 for surrounding the coil 12 so that the poles of the rotor opposed peripheral surface 20 alternately become opposite polarity. A rotor 16 has a permanent magnet ring 17 disposed oppositely to the outer periphery of the armature 10 and magnetized to alternately become different polarity, a cup-shaped yoke 18 attached to the ring 17 to cover the outer periphery of the ring 17 and one end, and a shaft 20 secured by a nut 19 to the center of the flat side of the yoke 18. The rotating speed detecting mechanism of the rotor 16 is used also as the ring 17 used for the rotor 16 as a generating magnet.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a multipolar DC motor, and more particularly to a multipolar DC motor particularly suitable for use in driving a floppy disk.

The motor for driving floppy disks must be thin;
It is also required to be able to control the rotation speed.

Conventional motors of this type can be broadly classified into the following three types.

(There is a two-phase multipole DC motor in which wires are wound in about 8 to 16 slots that open on the circumferential surface of a laminated core.
Because winding is extremely difficult and the core is laminated, the number of parts is large, and polishing costs are high, making it expensive. Furthermore, due to its structure, it is difficult to make it thin.

(b) It is a disk-shaped magnet with 6 points located concentrically on its plane.
It consists of a rotor with magnetized poles and a fixed armature with four flat coils arranged on a plate-shaped magnetic body facing the magnetic poles of the rotor. be.

This has the disadvantage that the number of turns in the coil cannot be increased sufficiently, resulting in poor power consumption efficiency, inability to obtain a large output, and high heat generation.Furthermore, the attraction force of the magnet is applied in the thrust direction, making it difficult to use as a bearing. Bearings have to be used, and there are problems in that the bearings have short lifespans, poor durability, and are expensive.

(c) There is a two-phase multi-pole DC motor which uses a sheet coil for the armature and is of the same plane-opposing type as the one described in (b) above.

This allows for a thicker space factor, which improves power consumption efficiency to some extent, but the sheet coil itself is expensive, making it the most expensive of the three types of motors.

In addition to each of the above three types of motors having their own unique problems as mentioned above, they are all two-phase drive, so two ball elements and two pairs of drive circuits are required to make them brushless. However, there is a problem in that it is expensive.

On the other hand, in order to control the rotational speed of the rotor, a power generation magnet that rotates together with the rotor is installed, and a power generation coil is placed opposite this power generation magnet, but at a frequency higher than the rotational speed of the rotor. In order to detect the rotational speed of the rotor until the magnetic pole of the rotor reaches the position of the adjacent magnetic pole and perform control with excellent responsiveness, even if a permanent magnet is used as the rotor, It was not possible to use the rotor's permanent magnet as the power generation magnet.

The present invention has been made in view of the above problem Gξ,
The purpose of this is to make the coil concentrically wound for easy assembly, and to drive it in a single phase so that only one ball element, etc.
It is possible to reduce the product cost with just one piece, has superior durability, and can increase the number of windings, resulting in 9 power consumption.
) The purpose of the present invention is to provide a DC motor that has a low J ratio and also uses a permanent magnet used as a rotor as a power generation magnet for detecting the rotational speed of the rotor. a rotor of a permanent magnet ring magnetized with 2n poles (n is a natural number of 2 or more) so as to have different polarities;
In order to generate 2n magnetic poles in which adjacent poles on the circumferential surface facing the rotor of a coil wound concentrically around the axis are different from each other, the coil is wrapped with a core along the magnetic path, and the core is The coil is branched into n pieces toward the rotor at both flat side faces of the coil, and the tips of the branched cores are intertwined alternately on the circular surface of the coil facing the rotor, and one or more tips are connected to the rotor. a fixed armature extending in the opposite direction to the rotational direction of the rotor; a ball element disposed opposite the rotor to switch the direction of current in the coil in response to the rotation of the rotor; and a power generator that rotates together with the rotor. magnet and
A point consisting of a power generation coil that is placed opposite to this power generation magnet and detects the rotational speed of the rotor, and a control circuit that controls the rotational speed of the rotor based on the detected value of this power generation coil, and a pole adjacent to the circumferential surface. The rotor is a permanent magnet ring magnetized with 2n poles (n is a natural number of 2 or more) so that the polarities are different from each other, and the rotor is adjacent to the peripheral surface facing the rotor of a coil wound concentrically around the axis. In order to generate 2n magnetic poles with different poles, the coil is wrapped in a core along the magnetic path, and the core is branched into n pieces toward the rotor at both flat side facing parts of the coil. A stationary armature in which the distal ends of the cores are intertwined alternately on the circumferential surface of the coil facing the rotor, and one or more distal ends extend in a direction opposite to the direction of rotation of the rotor; In order to switch the current direction of the coil in accordance with A power generation magnet is formed by branching so that the NS pole appears at the tip, a power generation coil is placed opposite to this power generation magnet and detects the rotational speed of the rotor, and the rotational speed of the rotor is determined based on the detected value of this power generation coil. It consists of a control circuit for controlling.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The figure shows the outer rotor, and the inner port,
- can be constructed in the same way.

First, the armature and rotor used in the present invention are shown in FIGS. 1 and 2 using a four-pole case as an example, and the rotation principle thereof is explained. 1 is a coil, which is concentric with a cylindrical bobbin 2. It is wrapped.

3 is a core, and one core 3a and the other core 3b are provided so as to cross each other when viewed from the rotating shaft side along the diameter of both side surfaces of the bobbin 2.
The tips of a and 3'b are bent at right angles along the outer peripheral side of the coil 1.

Further, the cores 3a, 3b are bent at right angles along the inner circumferential surface of the coil 1 and abutted against each other, and both cores 3a, 3'
b is magnetically coupled to the inner peripheral surface of the coil 1.

A rotor consisting of permanent magnets magnetized into four poles,
Assume that it rotates in the direction of the arrow.

5 is an extension of the core 3, which extends in a direction opposite to the rotational direction of the rotor 4 from the tips of both cores 3a, 3b.

Note that this extending portion 5 is provided at the entire tip of the core 3.
There is no need to do so, and it is sufficient to provide as many as necessary to start the motor.

゛ In this configuration, while the rotor 4 is rotating, the coil 1
By the switching means for switching the current direction, the magnetic poles appearing alternately on the outer peripheral surface of the coil 1 are converted into a direction that urges rotation of the rotor 4. Further, when the current to the coil 1 is cut off, the rotor 4 stops at the position where the magnetic resistance is the smallest, that is, the position shown in FIG. 2. When starting up, coil 1
When energized, the center of the magnetic pole of the armature shifts from the position where the magnetic resistance is minimum in the opposite direction to the rotating direction of the rotor 4 due to the influence of the extension portion 5, so that the rotor 4 stops at the starting dead center. This means that even if it is a single-phase drive, it will be activated reliably.

Next, an embodiment in which the armature and rotor configured as described above are used as a motor for driving a floppy disk will be described as shown in FIGS. 3 and 5.

Reference numeral 10 denotes an armature, which is composed of a coil 12 concentrically wound around the hobbin 11, and a core 13 surrounding the coil 12 so that 20 magnetic poles are alternately different on the circumferential surface facing the rotor.

Note that an extending portion 13a is formed at the branched tip of the core 13 in a direction opposite to the rotational direction of the rotor. Furthermore, as shown in FIG. 5, the branched tip of the core 13 may be provided with a protrusion 13b that protrudes in the opposite direction of the extension 13a. Since the magnetic flux has the property of being concentrated at the tip of the extending portion 13a and the tip of the protruding portion 13b, the efficiency of the motor can be improved. Further, the core 13 is formed by combining an upper core and a lower core so as to form a closed magnetic path on the inner peripheral surface of the coil 11.
Since a and the closed magnetic circuit portion 13C are press-worked as one body, manufacturing thereof becomes easy.

Reference numeral 14 denotes a fixing member fitted to the inner peripheral surface of the armature 10, and its flange portion 14'a is fixed to the substrate I5, and the armature 10 is fixed to the substrate 15.

Reference numeral 16 denotes a rotor, which includes a permanent magnet ring 17 arranged opposite to the outer peripheral surface of the armature 10 and magnetized so as to have different polarities alternately, and the outer peripheral surface and one end surface of this permanent magnet ring 17. It consists of a force/knob-shaped yoke I8 which covers the permanent magnet ring I7 and is attached to a permanent magnet ring I7, and a shaft 20 which is fixed to the center of the flat side of this II1 iron 18 with a nut 19. The shaft 20 is inserted into a hair ring 21 fitted to the inner circumferential surface of the fixed member 14, and the rotor is rotatable.

The yoke 18 only needs to be made of a magnetic material at least in the portion that comes into contact with the circular surface of the permanent magnet ring 17.

Reference numeral 22 denotes a ball element, and one ball element is installed on a printed circuit board 23 attached to the circuit board 15, facing the permanent magnet ring 17, in order to switch the current direction of the coil 12 by the rotation of the magnetic poles of the permanent magnet link 17. only.

Accordingly, as the rotor 16 rotates, the ball element 22 switches the current direction of the coil I2, and each of the cores 13'
Different poles are generated alternately at the tip of the rotor 16, and the rotation of the rotor 16 is continued. As a result, the turntable 24, which is fixed to the shaft 20 and into which a floppy disk (not shown) is fitted, rotates.

Next, the rotational speed detection mechanism of the rotor 16 will be explained.

In FIG. 3, the yoke 18 has a bent portion 18a whose peripheral edge is wide outwardly and bent at a right angle, and has a surface parallel to the printed circuit board 23.

Reference numeral 25 denotes a flat permanent magnet ring serving as a power generation magnet, which is attached to the bent portion 18a, and has 6 holes on its flat side in order to make the magnetic poles smaller than the magnetic pole pitch of the rotor IG.
The zero pole is alternately magnetized to N and S.

Reference numeral 26 denotes a power generation coil, which is printed and wired on the printed circuit board 23 so as to be close to and face the magnetized surface of the permanent magnet ring 25. The pitch of this power generating coil 26 is the same as the magnetic pole pitch of the permanent magnet ring 25.

Further, in FIG. 5, the permanent magnet ring 17 used in the rotor I6 also serves as a power generation magnet as the rotational speed detection mechanism of the rotor 16.

However, as shown in FIG. 7, the permanent magnet ring 17 is magnetized toward the axis, and the outer circumferential surface has the same number of magnetic poles that are different in polarity from the inner circumferential surface. has been done. The yoke 18 is branched so as to leave a portion facing the magnetic pole on the outer circumferential surface of the permanent magnet ring 7, and the tip of this branched portion 18b has a V-shaped shape along the circumferential surface of the permanent magnet ring 17. A V-shaped branch portion 18c is formed that spreads out, and the tips of the V-shaped branch portions 18c of adjacent branch portions 18b are close to each other. Therefore, the same number of pinch N and S poles as the magnetic poles of the permanent magnet ring 17 are formed on the outer periphery of the permanent magnet ring 17 facing the printed circuit board 23 and are smaller than the magnetic pole pitch of the permanent magnet ring 17.
A power generating magnet having magnetic poles with a smaller pitch than the magnetic pole pinch of the permanent magnet ring 17 is formed.

In this case, since the number of magnetic poles of the power generating magnet and the number of magnetic poles of the permanent magnet ring 17 are the same, the Hall element 22 is switched between the power generating magnets 1 to 1.

The power generation coils 26 are printed and wired on the printed circuit board 23 so that 2m+1 (m is a natural number of 1 or more) are arranged between the magnetic poles of the permanent magnet ring 17, and there are three in the illustrated case.

Therefore, the voltage induced in the power generation coil 26 by the rotation of the power generation magnet + is proportional to the rotation speed of the rotor 16, and the frequency proportional to the rotation of the rotor 16 is higher than the rotation speed of the rotor 16, and further, Since the magnetic pole pinch of the power generation magnet is smaller than the magnetic pole pitch of the rotor 16, the rotor 1 between the magnetic poles of the armature 10
A rotation speed of 6 is also detected.

The voltage or frequency induced in the generator coil 26 is input to a control circuit (not shown), and this control circuit controls the voltage supplied to the coil 12, etc., and the rotation of the rotor 16 is controlled to a desired speed. becomes.

Note that the power generation magnet and power generation coil are not limited to the above-mentioned embodiments, but the important thing is that the detection voltage is appropriate and that there is a connection between the magnetic poles of the armature. It is only necessary to be able to detect the rotational speed of the rotor. Therefore, for example, when the power generating coil 26 is arranged over the entire circumference, the power generating magnet does not have to be installed over the entire circumference, and conversely, when the power generating magnet is installed over the entire circumference, The generating coil may be partial. Further, instead of forming the tips of the branch portions 18b of the yoke 18 in a V-shape, the tips of adjacent branch portions 18b may be bent so as to approach each other.

Furthermore, the number of poles of the armature and rotor is not limited to the above-mentioned embodiment, but for a floppy disk drive, it is 6 to 4.
The 0 pole position is appropriate.

In this way, according to the present invention, by forming the armature coil in a concentric manner, the winding work becomes easy, the number of windings can be increased, and the power consumption efficiency can be improved. The number of poles can be easily changed by changing the number of branches in the core surrounding the armature, and since it is a single-phase drive, only one Hall element and its drive circuit are required to switch the current in the armature coil. Well, again,
The permanent magnet ring of the rotor can also be used as a power generation magnet for detecting rotor speed, which has the remarkable effect of reducing product costs.

Although the present invention has been variously explained above with reference to preferred embodiments, the present invention is not limited to these embodiments, and it goes without saying that many modifications can be made without departing from the spirit of the invention. It is about.

[Brief explanation of drawings]

FIG. 1 is a side view of the armature, FIG. 2 is a plan view of a motor using the armature shown in FIG. 1, FIG. 3 is a plan view of a motor according to the present invention, and FIG. 4 is A of FIG. -A sectional view, Fig. 5 is a developed view of the core, Fig. 6 is a plan view of a motor that serves as both a power generating magnet and a rotor magnet, Fig. 7 is a BB sectional view of Fig. 6, and Fig. 8 is a FIG. 3 is a developed view of the outer periphery of the rotor. 1... Coil, 2... Bobbin, 3.3a. 3b... Core, 4... Rotor, 5... Extension part,
10... Armature, 11... Bobbin, 12... Coil, 13... Core. 13a...extension part, 13b...projection part. 13C...Closed magnetic path section, 14...Fixing member. 14a...Flange portion, 15...Substrate. 16...Rotor, 17...Permanent magnet ring. 18... Yoke, 18a... Bent part, 18b... Branch part, 18c... V-shaped branch part 319... Nando,
20...Go to shirt 1. 21... Hair ring, 22... Hall element. 23... Printed circuit board, 24... Turntable,
25... Permanently sharpened 4-stone link, 26... Generator coil. Patent applicant Fumihito Komatsu Figure 1 Figure 2 Figure 3 River Figure 1 Figure 5 Figure 6 Story River 622 Figure 8 March 27, 1981 Kazuo Wakasugi, Commissioner of the Patent Office 1, Incident Display of 11594 68' mI mark 36768 death 2, name of invention multi-pole DC motor 3, corrector 4, i (Jl-). Vol. 6, Subject of amendment 1lIll Book 8, Contents of amendment 1) The phrase "Figure 5" in the first line of page 10 of the specification has been changed to "
Figure 6” is corrected. 2) In the 3rd line of page 13 of the specification, replace “Figure 5” with “
Figure 6” is corrected. 3) In the 6th line of page 13 of the specification, replace ``Figure 1 7'' with ``
Figure 8”. Procedural Amendment Document Patent Office & Manabu Koshiga 1, Indication of the case Patent Application No. 36768 of 1982 3, Relationship with the person making the amendment 41 cases Special 1 Applicant Residence: 1632 Hirooka Nomura, Shiojiri City, No. 1, Japan 124 of
Submit as an attachment to the agent. 13th t'A Bo Figure 6

Claims (1)

[Claims] 1. A rotor of a permanent magnet ring that is magnetized with 2n poles (n is a natural number of 2 or more) so that the poles adjacent to each other on the Ri surface are strongly different from each other, and In order to generate 2n magnetic poles in which adjacent poles are different from each other on the circumferential surface of the coil wound concentrically and facing the rotor, the coil is wrapped with a core along the magnetic path, and the core is wrapped around the coil along the magnetic path. 1 at the flat side facing part of both swords of the coil
1-branch into n pieces toward the rotor, intertwine the tips of the branched cores alternately on the circular surface of the coil facing the rotor, and insert one or more tips in the direction of rotation of the rotor. A fixed armature extending in the opposite direction, and a fixed armature arranged facing toward the rotor to change the current direction of the coil in response to the rotation of the echoter.111. The rotational speed of the Hall element 1, the generator magnet 1~ that rotates together with the rotor, and the motor that is placed opposite the generator magnet 1- is detected. -11 power generation': A multi-pole DC motor consisting of a Z coil and a control circuit that controls the rotational speed from beginning to end based on the detected value of this power generation coil. 2. A rotor with a permanent magnet ring magnetized with 2n poles (n is a natural number of 2 or more) so that adjacent poles on a circular surface are different from each other, and a rotor with a coil wound concentrically around the axis. In order to generate 2n magnetic poles in which adjacent poles on the circumferential surface facing the opposite poles are different from each other, the coil is placed in a magnetic path and wrapped in a core, and the core is connected to the rotor with both flat sides of the coil facing each other. The core is branched into n pieces, and the tips of the branched cores are intertwined alternately on the circumferential surface of the coil facing the rotor.
A fixed armature with one or more tip portions extending in a direction opposite to the rotational direction of the rotor, and one hole placed opposite to the rotor to switch the current direction of the coil in accordance with the rotation of the rotor. A power generating magneto 1 which is formed by branching an element, a yoke which is attached to a rotor and rotates together with the rotor, so that at least one pair of NS poles of the magnetized rakes of the rotor appear at the tip, and this power generating magnet. A multi-pole DC motor consisting of two power generating coils arranged opposite to each other to detect the rotational speed of the rotor, and a control circuit that controls the rotational speed of the rotor based on the detected value of the power generating coil.