JPS61231853A - Winding method for commutatorless dc motor coil and commutatorless dc motor - Google Patents

Abstract

PURPOSE:To eliminate the extreme decrease of a starting torque even near the switching point of an exciting current by forming a plurality of exciters at a yoke member of a stator, and magnetically coupling the coils of the exciters in a chain form. CONSTITUTION:Adjacent poles in which even number (m) of permanent magnets M1-Mm are disposed adjacently are inverted and arranged circularly in a rotor 1. the yoke member 3 of a stator 2 has (n) pieces of poles P1-Pn divided by 2m=n pieces of slots S1-Sn. Two exciters A, C and B, D of the first and second types are formed in the slots S1-Sn, and (m) pieces of coils are wired in series per one of the exciters A-D. The exciters A or B and C or D in which the coils are wound in a relation that he slots are displaced by one are magnetically coupled in a chain state in such a manner that each coil has at least one pole.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field) The present invention relates to a novel winding method for a commutatorless DC motor and a commutatorless DC motor obtained thereby.

(Prior art and its problems) Conventional non-commutated DC motors have problems with the resolution of the magnetic detection means 1, such as a Hall element, which detects the reversal of the magnetic poles of the permanent magnets, which are the rotor, and the reversal magnetic field of the permanent magnets. Due to the inability to obtain a sharp change, a dead center occurs in the direction of rotation of the rotor, and furthermore, there is a drawback that the starting torque decreases extremely near this dead center.

In order to eliminate this dead center, conventional methods have been used to prevent the rotor from stopping at the dead center, such as by establishing a mechanically stable stopping point for the rotor, or stabilizing the rotor using a static magnetic field. A motor with a stable point provided at the stop position of the rotor has the disadvantage of generating vibration and noise during rotation.

In addition, in order to eliminate the dead center without using the above-mentioned locking means, at least three Hall elements that detect the magnetic field of the rotor are used to reliably detect the rotational direction and determine the rotational direction of the rotor at the time of startup. However, this method has the disadvantage that the control circuit becomes complicated and expensive.

(Purpose of the Invention) The present invention aims to prevent dead points from occurring at all in the rotational direction of the rotor, regardless of the resolution of the Hall element and the speed and speed of one reversal change in the magnetic field, and at the same time, the switching point of the excitation current is It is an object of the present invention to provide a stator winding method that eliminates an extreme drop in starting torque even in the vicinity, and a commutatorless DC motor obtained by the winding method.

(Means for Solving the Problems) The present invention provides a yoke member of a stator having at least twice the number of permanent magnetic poles in the rotor, and a plurality of coils commonly wound around a plurality of adjacent poles. are connected in series to form a plurality of excitation circuits, and each coil of at least one pair of excitation circuits in the plurality of excitation circuits shares at least one or more poles related to the other excitation circuit. This invention relates to a method of winding a commutatorless DC motor coil that is magnetically coupled in a chain.

The present invention also provides a stator yoke member including a plurality of permanent magnets circularly arranged in a rotor with reversed polarity, a stator yoke member having at least twice the number of poles of the permanent magnets, and the yoke member. A first type excitation circuit is formed by connecting in series a plurality of coils commonly wound around a plurality of poles;
The coil of the excitation circuit of the species shares at least one or more of the plurality of commonly wound poles, and the first
a second type of excitation circuit formed by connecting in series a plurality of coils that are magnetically coupled to the first type of excitation circuit in a chain and commonly wound around a plurality of adjacent poles of the yoke member; and controlling the timing at which the excitation current is applied to either of the second type excitation circuits, so that when one is located at the polarity reversal portion of the permanent magnetic field, the other is located approximately at the center of the permanent magnetic field. The present invention also relates to a commutatorless DC motor comprising a pair of magnetic field detection means provided at appropriate positions on the stator.

(Example) Fig. 1 is a developed view schematically showing the winding state of the stator according to the present invention, and Fig. 2 is a developed view showing the specific winding state of Fig. 1 as viewed from the motor axis direction. FIG.

The rotor (1) has an even number m of permanent magnets (M+) to (M
m) are arranged in a circular manner with adjacent magnetic poles reversed.

The yoke member (3) of the stator (2) has n poles (Pl) to (Pn) separated by 2m=n slots (S+) to (Sn), and in the illustrated embodiment , m=
4, in the case of n=8.

Each slot (Sl) to (Ss) is provided with a first type excitation circuit (A) (C) and a second type excitation circuit (B) (D) by the novel winding method according to the present invention. Two circuits each are provided, and each excitation circuit (A) to (D) is m=
Four coils are connected in series.

Figure 3 a ” d indicates each excitation circuit (A) (B) (C)
(D) shows the winding state for each type, and Figure 3a shows the first type excitation circuit (A), the second type excitation circuit (B), and the same type C
is the first type excitation circuit (C), and d is the second type excitation circuit (C).
D) are shown in order.

As shown in the figure, each excitation circuit (A) to (
Each coil (A1) to (A4), (B1) to D)
(B4), (C+) ~ (C4), (Dl) ~ (B4) have every other slot (S) and one coil is common to two adjacent poles (P). is wrapped around.

Similar excitation circuits (A) and (C), or (B) and (
Each coil in D) is wound in multiple turns around the same two poles, and different types of excitation circuits (A) or (B) and (C
) or (D), the coils between each circuit are wound with one slot shifted from each other.

These excitation circuits (A) or CB) and (C) or (D), which are wound with the slots shifted by one, are two coils wound in common in the same type of excitation circuit. In excitation circuits of different types, at least one pole is shared by coils of different types, and the poles are coupled in a chain.

The wiring of each coil in each excitation circuit (A) to (D) is the first
As shown in Figures and Figure 3, when current flows through each of the excitation circuits (A) to (D), the wires are connected so that the directions of the magnetic fields generated in adjacent coils in one excitation circuit are opposite to each other. has been done.

Furthermore, the same type of excitation circuits (A) and (C), or.

In each of the coils (B) and (D), the direction of the excitation current is determined so that when current flows through each excitation circuit, the multi-wound coils generate magnetic fields in opposite directions. Two or more excitation circuits do not allow excitation current to flow through them at the same time.

In addition, the direction of the current flowing to each excitation circuit is uniquely determined to be one direction in order to simplify the control circuit, so the same type of excitation circuits (A) and (C), or (B) and (D ), but one circuit is sufficient for each if the direction of the current flowing to the excitation circuit is controlled in both directions, as shown in FIG. 5 of the embodiment described later.

Both terminals (a, ) of each excitation circuit (A) to (D) (a,
), (bl) (b2), CC,) (C,), (di
) (d2) is the current inflow end (ai) (b
i) (cl) (dx) side to positive power supply (+),
Also, the outflow end (as) (bz) (cz) (
dz ) side is an NPN transistor (Ta) (Tb) (T
c) are respectively connected to the collectors of (Td), and
The emitter of each transistor (Ta) to (Td) is connected to a negative power supply (-) (ground).

Furthermore, the bases of the transistors (Ta) and (Tc) in the first type excitation circuits (A) and (C) are respectively connected to the Hall electromotive force output terminal of one Hall element (Hx) that detects the current switching point. Similarly, the second type of excitation circuit (
B) Each base of the transistors (Tb) (Td) in (D) is connected to the other Hall element (
Hx) are connected to the Hall electromotive force output terminals.

The Hall elements (Hx) (Hy) are permanent magnets (M2) (M
4), when a magnetic field is applied in the direction of the solid arrow shown in the figure, the bases of the transistors (Ta) and (Tb) of the excitation circuits (A) and (B) have positive polarity, and the permanent magnet (Ml) When approaching the S pole of (M3) and applying a magnetic field in the direction of the dotted arrow shown in the figure, the excitation circuit (C) and (D
), the bases of the transistors (Tc) and (Td) are set to positive polarity, and at this time, the transistor whose base is set to positive polarity is turned on and causes an excitation current to flow through each coil in the direction of the arrow.

When one of the pair of Hall elements (Hx) (Hy) is located at the polarity reversal portion of the permanent magnets (Ml) to (M4), the other is located approximately at the center of any of the permanent magnets (Ml) to (M4). The stator is provided at an appropriate location so that the

In the embodiment, a Hall element (Hy) is fixed to the side surface of the second pole (P2), and a Hall element (Hx) is fixed to the side surface of the seventh pole (P7).

In the case of the example, as shown in Fig. 1, a permanent magnet (M3) (
The Hall element (H
x), the central part of the permanent magnet (Ml) is
A Hall element (Hy) is located there.

Position 1 of such a relative relationship, for example, a Hall element (H
If z) is left as it is at the 7th pole, the Hall element (
Hy) are the 4th, 6th, and 8th poles (P4) (P i)
(Ps).

However, when the Hall element (Hy) is provided at the second pole (P2), the polarity of the permanent magnet (Ml) is the S pole, and the Hall element (Hy) transfers the electromotive force to the transistor (Ta>
(Tb) as shown in the figure, and if the operation described below is performed properly, the Hall element (Hx) is connected to the fourth,
When transferred to either of the eighth poles (P4) (Pg), the polarity of the permanent magnets (M2) (M4) is the N pole opposite to that of the permanent magnet (Ml), so the transistor ( The polarity applied to the base of ra) (Tc) must be reversed.

(Operation) Next, the operation of the commutatorless DC motor according to the present invention will be described in the first section.
This will be explained based on the diagram.

The Hall element (H2) shown in Fig. 1 is connected to a permanent magnet (M3) (
The position at the polarity reversal part of M4) corresponds to the dead center of conventional non-commutated motors, and if the rotor is stopped here, it is impossible to start or the starting torque is very low. , is the position where the torque to start the load cannot be obtained.

The polarity reversal part, which is the abutting part of the permanent magnets (Ml) to (M4), is caused by the magnetic sensitivity and resolution of the Hall element (Hz) or (Hy), as well as the temperature and speed of the magnetic flux change of the reversal magnetic field. ) (Hy) has a width for sensing magnetic reversal, and the shaded area in this figure is called a dead zone, and the wider this width, the wider the dead center range.

In the motor of the present invention, when the Hall element (Hz) is in this dead zone, the other Hall element (Hy) is located approximately at the center of the permanent magnet (M+) and is reliably sensitive to the magnetic field of its S pole. The resulting electromotive force turns on the transistor (Tc), and the first type excitation circuit (C
) in the direction of the arrow.

When the transistor (Tc) is turned on, each coil (C1) to (C4) of the excitation circuit (C)
Two poles (Pl) and (Pl), (P3) and (P a
).

When (Ps) and (PF, ), (Pl) and (Ps) are the maximum magnetic flux density that can be generated in each pole as 100%,
It is magnetized in 50% increments (however, leakage magnetic flux is ignored in this study).

At this time, 2
The individually magnetized pole pairs are composed of permanent magnets (Ml) to (
With respect to the center of the permanent magnet (M4) (the center of the segmented magnetic pole S or N with respect to the rotor rotational direction), the center is shifted by an angle of 45° corresponding to the pole pitch angle and is magnetized to have an opposite polarity. +) to (M4) to rotate the rotor in the direction of the arrow (R).

When the rotor rotates slightly, the Hall element (Hz) escapes from the dead zone and enters the magnetic field of the N pole of the permanent magnet (M4),
thereby turning on the transistor (Td),
An excitation current is passed through the second type excitation circuit (D), and at this time,
Excitation current flows simultaneously through the first type and second type excitation circuits (C) and (D).

Each coil (C) of the first and second type excitation circuits (C) (D)
1) to (C4), (Dl) to (D4) are each pole (P
l) ~ (Pg) are shared and connected in a chain, so
Each pole (P+) - (Pa) connects both excitation circuits (C) (
D) is magnetized by each coil of the same polarity, the magnetic flux is twice the magnetic flux density obtained by each coil, i.e. the maximum magnetic flux density in this motor is 1
00%, and when the polarities are opposite, the magnetic flux cancels out and becomes 0, and as a result, specifically, 1.3.5.7
Each pole (P +) (P:1) (Ps) (P)) is 1
Excited to 00%.

Each pole (Pl) excited to 100%...
The permanent magnets (M+) to (M4) that are close to it are excited in the pre-started rotation direction with an advanced phase and opposite polarity, and the rotor generates a large torque in that direction.

Immediately before the centers of the permanent magnets (Ml) to (Ml) reach the center of the 100% excited pole (Pl), the Hall element (Hy) moves between the permanent magnets (Ml) and (Ml). Entering the dead zone, the transistor (T c ) is cut off, the Hall element (Hz) is located approximately at the center of the permanent magnet (M4), and only the second type excitation circuit (D) continues to operate.

In this second type of excitation circuit (D) alone, a pair of adjacent poles (Ps) (P+), (Pl) (P3), (Pa
) (P 5) (P s) (P y) is excited to 50% for each pole, and the center of the pole pair is in a lead phase than the center of each permanent magnet (Ml) to (M4), and the polarity is opposite. It has become.

In this way, the first type excitation circuit (A) operates simultaneously with the second type excitation circuit (D), and then only the circuit (A) operates as the primary circuit (A). (B), then circuit (B)
circuits (B) and (C), then only circuit (C), and so on.

In this way, the first type excitation circuits (A) and (C) and the second type excitation circuits (B) and (D) operate alternately and simultaneously except in the dead zone to generate a large torque.

Further, even when only one of the first type and the second type is activated, a magnetic velocity density close to 50% can be generated.

Furthermore, the advancing angle of the pole that has 100% magnetic flux after entering the dead zone of either Hall element (Hz) (Hy) is, in the ideal phase relationship of the Hall element (Hz) (Hy), the pole Since the pitch angle is 45°, the allowable range for positional misalignment of the Hall elements (Hz) (Hy) that would generate reverse torque can be obtained with a margin of one pole pitch angle.

Therefore, the accuracy of installing the Hall element (Hz) (Hy) may be very low, and the accuracy of the installation of the Hall element (Hz) (Hy)
is usually attached to the side of the pole, so there will be no error at all if it is attached at an angle greater than the pole pitch angle.

(Other embodiments) Fig. 5 shows the first type excitation circuit (A) shown in Fig. 3 a and b.
and an excitation circuit (A') similar to the second type excitation circuit (B).
(B') is made to perform the same operation as in the previous embodiment using only one circuit.

Both excitation circuits (A') (B') include transistors (T A + ) to (TAa), (T
The excitation current is bidirectionally controlled by B + ) to (TBa).

That is, the transistors (T A +) and (Ta2) are a differential type converter using an operational amplifier that determines the polarity when the Hall element (Hy) is in the N-pole magnetic field.
At this time, the excitation circuit (A') generates a magnetic field in the same direction as the excitation circuit (C) of the embodiment of FIG. 1.

Furthermore, when the Hall element (Hy) is in the S-pole magnetic field, the transistors (T A3) and (Ta4) are turned on and apply a magnetic field in the same direction as the excitation circuit (A) of the embodiment shown in FIG. Occur.

Similarly, the transistors (TB+) and (TB2) are turned on by the differential comparator (OPe) when the Hall element (Hz) is in the N-pole magnetic field, and then the excitation circuit (B') It operates in the same way as the excitation circuit (D) in Figure 1, and the transistors (TB:i) and (TB
4) When the Hall element (Hz) is in the magnetic field of the S pole,
The excitation circuit (B') then operates in the same manner as the excitation circuit (B) of FIG.

In addition, in FIG. 5, (I A) (I B) are inverters,
(Z) is a Zener diode, and (r) is a current limiting resistor.

(Effects of the present invention) As described above, according to the winding method of the present invention, it is possible to create a commutatorless motor that stably starts without any dead center, regardless of the stopping position of the rotor. The motor of the present invention manufactured by the bracket winding method is structurally and electrically balanced without generating vibration or noise.

[Brief explanation of the drawing]

The figures show an embodiment of the present invention. Figure 1 is a developed view schematically showing the winding state of a commutatorless motor wound by the method of the present invention, and Figure 2 is the same as Figure 1. 3 is a front view of the stator and rotor viewed from the axial direction, and FIG. 3 is a front view similar to FIG. 2 showing the windings of the coils for each excitation circuit. FIG. 4 is an electric circuit diagram showing a drive circuit for the commutatorless motor shown in FIG. 1, and FIG. 5 is an electric circuit diagram of a drive circuit for a commutatorless motor showing another embodiment. (1) Rotor (2) Stator (3) Yoke member (Sl) ~ (8th) Slot (Pl) ~ (B
8) Pole (Hz) (Hy) Hall element (Ta) (
TbHTc) (Td) Transistor (TA+) (Ta
2) (Ta3) (Ta4) Transistor (TB+) (
TBz) (TB3) (TBJ Transistor (a) (b
) (c) (d) Inflow terminal (az) (b2) (C2) (dz) Outflow terminal (op^)
(OPe) Comparator (A) (C) (A') Type 1 excitation circuit (B) (D) (B') Type 2 excitation circuit (A1) to (A4) Coil (B1) to (B4) Coil (Cri ~ (C4) coil (D+) ~ (D4) coil

Claims (2)

[Claims] (1) A plurality of excitation circuits each consisting of a plurality of coils commonly wound around a plurality of adjacent poles are connected in series to a yoke member of the stator having at least twice the number of permanent magnetic poles as the number of permanent magnetic poles in the rotor. A circuit is formed, and each coil of at least one pair of excitation circuits in the plurality of excitation circuits is magnetically coupled in a chain by sharing at least one or more poles related to the other excitation circuit. A method of winding a commutatorless DC motor coil. (2) a plurality of permanent magnets arranged circularly in a rotor with reversed polarity, a yoke member of the stator having at least twice the number of poles of the permanent magnets, and a plurality of the yoke members. a first type excitation circuit formed by connecting in series a plurality of coils commonly wound around a pole; and at least one of the plurality of poles around which the coils of the first type excitation circuit are commonly wound. A second coil is formed by connecting in series a plurality of coils that share a pole of the yoke member, are magnetically coupled in a chain with the first type excitation circuit, and are commonly wound around a plurality of adjacent poles of the yoke member. The timing at which the excitation current is applied to either the excitation circuit of the seed and the excitation circuits of the first type and the second type is controlled, and when one is located at the polarity reversal part of the permanent magnetic field, the other is placed in the permanent magnetic field. and a pair of magnetic field detection means provided at appropriate positions on the stator so as to be located approximately in the center of the stator.