JPH09252592A - Brushless motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the harmful influence of the variation in amplitudes of detection signals upon generated torque by a method wherein relative positions between a field and 3-phase coils are detected and detection signals of 2 different phases are obtained and 3-phase switching signals which are varied smoothly are generated in accordance with the detection signals of the 2-phases. SOLUTION: A command unit 15 outputs 1st and 2nd output current signals in accordance with command signals R and supplies the signals to a 1st distributor 31 and a 2nd distributor 32 in a distributor 13. A position detector 21 outputs 2-phase detection signals from 2 position detection devices and a switching signal generator 22 synthesizes the detection signals of 2 phases arithmetically and generates 3-phase switching signals having 120 deg. phase difference between each other and supplies them to the distributor 32. As a result, the influences of the variation in sensitivity of the position detection devices in the position detector 21, the variation in magnetic field of a field unit 10 and the variation in circuit gain of the switching signal generator 22 are significantly reduced and the influences can be practically neglected.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brushless motor that detects the position of a rotor and energizes a coil.

[0002]

2. Description of the Related Art In recent years, brushless motors have been used in which the rotational position of a rotor is detected by a Hall element and the energization of a three-phase coil is switched according to the detected output (for example, JP-A-55-166495). See the bulletin). FIG. 29 is a block diagram showing the structure of a conventional brushless motor. The magnetic pole of the rotor rotating magnet 2001 is set to the hall element 201.
1, 2012 and 2013 detect and output a three-phase detection signal corresponding to the rotational position. Each Hall element 2011,
The outputs of 2012 and 2013 are amplifier 202, respectively.
1, 2022 and 2023 amplify the output to a predetermined multiple. Multipliers 2031 2032 and 2033 respectively multiply the outputs of amplifiers 2021, 2022 and 2023 with the command signal of command device 2050, and obtain three-phase multiplication signals with amplitudes corresponding to the command signals. Power amplifiers 2041, 2
042 and 2043 are multipliers 2031 and 20 respectively.
The outputs of 32 and 2033 are power-amplified and three-phase coil 2
002, 2003 and 2004. Thus,
A three-phase drive signal that changes with the rotation of the rotor magnet 2001 is applied to the three-phase coils 2002, 2003, and 2004, and the rotor magnet 2001 continues to rotate in a predetermined direction.

[0003]

However, the conventional structure as described above has the following problems. The amplitude of the drive signal is the same as the command signal from the command device 2050 and the Hall element 201.
It is proportional to the result of multiplication with the amplified signal of the outputs of 1, 2012 and 2013. However, due to variations in the sensitivity of the Hall element and variations in the magnetic field of the rotor magnet 2001,
The amplitudes of the detection signals of the Hall elements 2011, 2012, and 2013 vary, and as a result, the multiplier 2031,
The outputs of 2032 and 2033 and the amplitude of the drive signal vary. Especially, the variation in sensitivity of the Hall element is very large, and the variation in the amplitude of the output of the Hall element is a major factor causing the large variation in the amplitude of the drive signal. Conventionally, the three Hall elements in each motor are matched so that the sensitivity ranges of the Hall elements match each other, and adjustment is performed so that the influence of relative sensitivity variations is reduced. However,
When viewed in a large number of mass-produced motor groups, large amplitude variations of the drive signal remained due to variations in the sensitivity of the Hall element among the motors. This variation in amplitude causes variation in the torque generated by the motor with respect to the command signal from the command device 2050, which has been a serious problem in using the brushless motor. Moreover, since three Hall elements are attached to the motor, the number of parts is large, the configuration is complicated, and the manufacturing process is complicated.

The present invention has been made in order to solve the above-mentioned conventional problems, and even if the amplitude of the detection signal of the detection element varies, the adverse effect on the generated torque due to it is extremely reduced. Brushless motor,
The purpose is to provide with a simpler configuration.

[0005]

The brushless motor of the present invention is provided with position detecting means for detecting the relative positions of the field and the three-phase coil to obtain two-phase detection signals having electrically different phases. A switching creation means is provided for generating a three-phase switching signal that smoothly changes according to a two-phase detection signal. The output current signal corresponding to the command signal is distributed according to the switching signal thus generated, and the drive signal is obtained based on the distribution. As a result, the amplitude of the distributed signal is hardly influenced by the change in the amplitude of the detection signal of the position detecting means, so that the value reliably corresponds to the command signal. as a result,
The drive signal supplied to the terminals of the three-phase coil is not affected by the variation in the detection output of the position detection means, and an accurate drive signal according to the command signal can be given. Also,
Since the position detecting means is provided for only two phases, the number of parts is small and the motor structure is extremely simple.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION A brushless motor according to the present invention has a field means for generating a field magnetic flux, a three-phase coil interlinking with the field magnetic flux, and two positions electrically different from each other by a predetermined phase. 2 arranged only for detecting the relative position between the field means and the three-phase coil and electrically different in phase from each other.
Position detection means for obtaining a phase detection signal, switching preparation means for obtaining at least one set of three-phase switching signals that smoothly changes according to the two-phase detection signals obtained by the position detection means, and a command signal A command means for obtaining a corresponding current signal, and a first output current signal of the command means for distributing to a three-phase first distribution current signal that smoothly changes according to the three-phase switching signal of the switching creating means. A first distributing means, and a second distributing means for distributing the second output current signal of the commanding means to a three-phase second distributing current signal that smoothly changes according to the three-phase switching signals of the switching creating means, A synthesizing unit for synthesizing the first distribution current signal and the second distribution current signal to obtain a 3-phase distribution signal, and a driving signal corresponding to the 3-phase distribution signal obtained by the synthesizing unit for the 3-phase Drive means for supplying to the terminals of the coil That.

In the first distributing means, the three first diodes to which the three-phase switching signals supplied from the switching creating means should be applied, and the base terminal side are connected to one end of the first diode, The emitter terminal side to which the output current signal of the command means is to be supplied is commonly connected, and three first distribution transistors for obtaining three-phase first distribution current signals from the collector terminal side can be included.

In the second distributing means, the three second diodes to which the three-phase switching signals supplied from the switching creating means are to be applied, and the base terminal side are connected to one end of the second diode. The emitter terminal side to which the output current signal of the command means is to be supplied is commonly connected, and three second distribution transistors for obtaining the three-phase second distribution current signals from the collector terminal side can be included.

In the first distributing means, the three first diodes to which the three-phase switching signals supplied from the switching creating means are to be applied, and the base terminal side are connected to one end of the first diode, The emitter terminals to which the first output current signal of the command means is to be supplied are connected in common, and three first distributed current signals of three phases are obtained from the collector terminal side.
The second distributing means includes three second diodes to which a three-phase switching signal to be supplied from the switching generating means should be applied, and one end of the second diode. The base terminal side is connected, the emitter terminal side to which the second output current signal of the command means is to be supplied is commonly connected, and the third phase second from the collector terminal side is connected.
It is configured to include three second distribution transistors for obtaining a distribution current signal, and the combining means obtains a difference current of each phase of the first distribution current signal and the second distribution current signal, It can be configured to include three resistors to which a three-phase combined distribution current signal according to the difference current is to be supplied.

The command means obtains a harmonic signal corresponding to the two-phase detection signals of the position detecting means, multiplies the command signal by the harmonic signal, and currents containing the harmonic signal component. It may be configured to include means for obtaining a signal and supplying a first output current signal and a second output current signal corresponding to the current signal to the first distribution means and the second distribution means, respectively.

The command means is responsive to the command signal.
Command current means for obtaining one command current signal and a harmonic signal corresponding to the two-phase detection signals of the position detecting means, and one command current signal of the command current means is multiplied by the harmonic signal. A multiplication command means for obtaining a multiplication command current signal, a combined command current signal obtained by combining the other command current signal of the command current means with the multiplied command current signal, and a first command corresponding to the combined command current signal. The output current signal and the second output current signal may be configured to include current combining means for outputting the output current signal and the second output current signal to the first distributing means and the second distributing means, respectively.

The command means multiplies a harmonic signal that changes six times per one cycle of the detection signal according to the two-phase detection signals of the position detection means and one command current signal of the command current means. It can be configured by including a multiplication command means for obtaining a multiplication command current signal.

The multiplication command means compares the absolute value signal of the three phases with the absolute value means for obtaining the absolute value signal of the three phases according to the detection signals of the two phases of the position detecting means, and the absolute value signal. Harmonic means for obtaining a harmonic signal according to the minimum value of

The synthesizing means is the first of the first distributing means.
It is also possible to obtain a difference current of each phase between the distribution current signal and the second distribution current signal of the second distributing means, and generate a distribution signal in which the difference currents for at least two phases are combined.

The switching creating means arithmetically synthesizes the two-phase detection signals of the position detecting means and electrically substantially 12
You may make it produce | generate the switching signal of three phases which have a phase difference of 0 degree.

In the brushless motor of the present invention, field means for generating a field magnetic flux, three-phase coils interlinking with the field magnetic flux, and relative positions of the field means and the three-phase coil. And a position means for obtaining at least one set of three-phase switching signals according to the two-phase detection signal, and in synchronization with the two-phase detection signal of the position means. A multiplication signal of a harmonic signal that changes six times per cycle of the detection signal and a predetermined command signal is used, and a harmonic component proportional to the command signal and including a predetermined proportion of the harmonic component corresponding to the multiplication signal is included. A command means for producing an output current signal, a distributing means for obtaining a three-phase distribution signal according to a multiplication result of the output current signal of the command means and the three-phase output signal of the position means, and the three-phase of the distributing means. The drive signal having a voltage waveform corresponding to the distribution signal of Comprising a drive means for supplying to the coil terminals.

The command means includes command current means for obtaining two command current signals in response to the command signal, and 6 per cycle of the detection signal in response to the two-phase detection signals of the position means.
Multiplying command means for obtaining a multiplying command current signal obtained by multiplying one of the command current signals of the command current means and the harmonic signal, and the other command current signal of the command current means It may be configured to include a current synthesizing unit that obtains a synthetic command current obtained by synthesizing the multiplication command current signal and the multiplication command current signal and outputs an output current signal corresponding to the synthetic command current signal.

The command means is an absolute value means for obtaining a three-phase absolute value signal according to the two-phase detection signals of the position means,
Harmonic means for comparing the three-phase absolute value signals to obtain a harmonic signal corresponding to the minimum value of the absolute value signals may be included.

Further, the brushless motor of the present invention is arranged only at two positions, which are field means for generating a field magnetic flux, a three-phase coil interlinking with the field magnetic flux, and electrically different from each other by a predetermined phase. Position detection means for detecting the relative positions of the field means and the three-phase coil to obtain two-phase detection signals electrically different in phase, and the two-phase detection obtained by the position detection means. 3 of the switching creating means, a switching creating means for creating a three-phase switching signal based on the signal, an instruction means for outputting a current signal according to a predetermined instruction signal, and the switching creating means.
Distribution means for distributing the output current signal of the command means into three-phase distribution current signals whose total sum is equal to the output current signal according to the phase switching signal, and a voltage waveform proportional to the distribution current signal. Drive means for supplying the drive signal of (3) to the terminals of the three-phase coil.

[0020]

【Example】

Example 1 Hereinafter, Example 1 of the present invention will be described with reference to the drawings. 1 to 6 are drawings regarding a brushless motor according to a first embodiment. FIG. 1 is a block diagram showing the overall configuration. The field unit 10 of FIG. 1 is attached to a rotor or a moving body, and forms a plurality of field magnetic poles by the magnetic flux generated by the permanent magnet magnetic poles to generate the field magnetic flux. The three-phase coils 11A, 11B and 11C are
They are attached to a stator or a fixed body and are electrically connected to each other at a predetermined angle (1
They are arranged offset by 20 degrees.

FIG. 2 shows the field part 10 and the three-phase coil 11A.
It is a figure which shows the concrete arrangement | positioning structure of 11B and 11C.
The annular permanent magnet 102 attached to the inner side of the rotor 101 has its inner surface and end surface magnetized to have four poles.
The field part 10 of FIG. 1 is formed. An armature iron core 103 is arranged at a stator position facing the magnetic poles of the permanent magnet 102, and the armature iron core 103 has three salient pole portions 104a, 10a.
4b and 104c are provided at intervals of 120 degrees. 3
The phase coils 11A, 11B and 11C are wound around the salient pole portions 104a, 104b and 104c, respectively. The winding grooves 106a, 106b and 106c formed between the salient pole portions 104a, 104b and 104c, respectively, are used as a working space during winding. Each coil 11A,
11B and 11C are electrically provided with a phase difference of 120 degrees with respect to the interlinkage magnetic flux from the permanent magnet 102 (N
One set of poles and south poles corresponds to an electrical angle of 360 degrees).
Two position detecting elements 107a and 107 are provided on the stator side.
b (for example, a Hall element which is a magnetoelectric conversion element is used) is arranged to detect a magnetic pole on the end surface of the permanent magnet 102 to detect a two-phase detection signal corresponding to a relative position between the field magnet portion and the coil. Trying to get. In this embodiment, the phases of the center of the coil and the center of the position detecting element are shifted by 90 degrees in terms of electrical angle.

The command unit 15 of FIG. 1 is composed of a command current unit 50, which outputs first and second output current signals according to the command signal R, and the first distributor 31 and the second distributor 31 in the distribution unit 13. Supply to the distributor 32. FIG. 3 is a circuit diagram showing a specific configuration of the command current device 50. + Vcc (= 9V) and-
In the circuit to which Vcc (= -9V) is applied, the transistors 121 and 122 and the resistors 123 and 124 form a differential circuit, and the current value of the constant current source 120 is changed to the collector of the transistors 121 and 122 according to the command signal R. Distribute to the side. The collector currents of the transistors 121 and 122 are compared by the current mirrors of the transistors 125 and 126, and the difference current is compared to the transistors 127 and 128.
And 129 through the current mirror. Thus, the first output current signal d1 and the second output current signal d2
And (d1 and d2 are outflow currents). Therefore, the output current signals d1 and d2 maintain the same current value according to the command signal R. In addition, the command signal R is ground potential 0
When it becomes smaller than V, the output current signals d1 and d2 become large. The first output current signal d1 is supplied to the first distributor 31 in the distributor 13 in FIG. 1, and the second output current signal d2 is supplied to the second distributor 32.

The position section 12 in FIG. 1 is composed of a position detector 21 and a switching generator 22. Position detector 21
Uses a two-phase detection signal from the two position detection elements 107a and 107b to generate a three-phase switching signal as described later, and supplies it to the first distributor 31 and the second distributor 32 of the distributor 13. . FIG. 4 shows the position detector 21 and the switching generator 22.
3 is a circuit diagram showing a specific configuration of FIG. The two position detection elements 107a and 107b of the position detector 21 are connected in parallel to each other and are supplied with a voltage via the resistor 131. The field detector 10 is provided at the output terminal of the position detecting element 107a.
Differential detection signals e1 and e2 corresponding to the magnetic field detected from (corresponding to the permanent magnet 102 in FIG. 2) are output (e1).
And e2 change in opposite phases. ). The detection signals e1 and e2 are the bases of the differential transistors 141 and 142 of the switching generator 22 and the differential transistors 161 and 1, respectively.
It is supplied to each of the 62 bases. Similarly, differential detection signals f1 and f2 corresponding to the magnetic field detected from the field unit 10 are output to the output terminal of the position detection element 107b, and the bases of the differential transistors 151 and 152 and the differential transistors 164 and 165 are output. Are supplied to each base.

Two position detecting elements 107a and 107b
Outputs two-phase detection signals e1 and f1 and e2 and f2 having a phase difference of 120 degrees electrically from each other.
The phase detection signals e1 and f1 or e2 and f2 are the field part 1
It smoothly changes into a sine wave shape or a substantially sine wave shape with the rotational movement of 0. Since the detection signals e1 and e2 or f1 and f2 are in an anti-correlation system with each other, the number of substantially independent phases is two in terms of handling.

Constant current sources 140, 14 of the switching generator 22
7, 148, 150, 157, 158, 160, 16
3, 170 and 171 respectively flow a predetermined current value into the circuit. The differential transistors 141 and 142 are responsive to the detection signals e1 and e2, respectively, to generate the constant current source 140.
The current value of is distributed to the collector side. Transistor 141
The collector current of the transistor 14 is amplified twice by the current mirror of the transistors 143 and 144.
The switching signal h1 is obtained from the connection point between the collector output of No. 4 and the constant current source 147. The collector current of the transistor 142 is doubled by the current mirror of the transistors 145 and 146, and is switched through the current mirror of the transistors 174 and 175 connected to the connection point between the collector output of the transistor 146 and the constant current source 148. The signal i1 is obtained.

Similarly, the differential transistors 151 and 15
2 distributes the current value of the constant current source 150 to the collector side in response to the detection signals f1 and f2, respectively. The collector current of the transistor 151 is the transistors 153 and 15
The signal is amplified twice by the current mirror 4 and the switching signal h2 is obtained from the connection point between the collector output of the transistor 154 and the constant current source 157. The collector current of the transistor 152 is doubled by the current mirror of the transistors 155 and 156, and is switched by the current mirror of the transistors 176 and 177 connected to the connection point between the collector output of the transistor 156 and the constant current source 158. The signal i2 is obtained.

The differential transistors 161 and 162 respond to the detection signals e1 and e2, respectively, and the constant current source 160.
The current value of is distributed to the collector side. Differential transistor 1
64 and 165 distribute the current value of the constant current source 163 to the collector side in response to the detection signals f1 and f2. The collector currents of the transistor 162 and the transistor 165 are combined and amplified twice by the current mirror of the transistors 166 and 167. The switching signal h3 is obtained from the connection point between the collector output of the transistor 167 and the constant current source 170. The collector currents of the transistors 161 and 164 are combined and amplified twice by the current mirror of the transistors 168 and 169. Transistor 17 connected to the connection point between the collector output of transistor 169 and constant current source 171
Via the current mirrors 8 and 179, the switching signal i3
Is getting The constant current sources 140, 147, 148,
The current values of 150, 157, 158, 160 and 163 are the same, and the constant current sources 170 and 171 are set to double the current value.

The switching signals h1, h2, and h3 are three-phase current signals (switching current signals) that smoothly change according to the two-phase detection signals, and are supplied to the first distributor 31 in FIG. Note that the switching signals h1, h2, and h3 become outflow current signals when viewed from the switching generator 22 due to the configuration of the first distributor 31 described later. The switching signals i1, i2, and i3 become three-phase current signals (switching current signals) that smoothly change according to the two-phase detection signals, and are supplied to the second distributor 32. Note that the switching signal i
1, 1, i2 and i3 are inflow current signals when viewed from the switching generator 22. The switching signals h1 and i1 alternately increase the current value. Similarly, the switching signals h2 and i2 alternately increase the current value, and the switching signals h3 and i3 alternately increase the current value (see waveforms (b) and (c) in FIG. 7 described later).
In this way, the switching generator 22 of the position portion 12 arithmetically combines the two-phase detection signals to generate two sets of three-phase switching current signals electrically having a phase difference of 120 degrees or approximately 120 degrees. Is producing.

The first distributor 31 in the distributor 13 of FIG.
In response to the switching signals h1, h2, and h3 of the switching generator 22, the first output current signal d1 is distributed to obtain a three-phase first distribution current signal. The second distributor 32 responds to the switching signals i1, i2 and i3 of the switching generator 22 to obtain the three-phase second distributed current signal which is the distribution of the second output current signal d2. The combiner 33 combines the first distributed current signal and the second distributed current signal to generate a three-phase distributed signal, and supplies it to the drive unit 14.
FIG. 5 shows the first distributor 31 and the second distributor 3 in the distributor 13.
2 is a circuit diagram showing a specific configuration of 2 and a combiner 33. FIG.
In FIG. 5, the switching signal h input to the first distributor 31
1, h2 and h3 are the first diodes 180,
Current flows into 181 and 182, and h1, h2, and h3
Generates a voltage signal corresponding to the inflow current value of. One ends of the first diodes 180, 181, and 182 are commonly connected, and the other ends of the first diodes 180, 181, and 182 are connected to the first distribution transistors 185 and 1, respectively.
It is connected to each base terminal of 86 and 187.

The first output current signal d1 from the command unit 15 (FIG. 1) is supplied to the commonly connected emitter terminal sides of the first distribution transistors 185, 186 and 187 via the current mirrors of the transistors 188 and 189. To be done. Therefore, the first distribution transistors 185, 186 and 187 respond to the switching signals h1, h2 and h3 to generate the first distribution transistors 185, 186 and 187.
The output current signal d1 of 1 is distributed, and three-phase first distribution current signals j1, j2, and j3 (inflow current) that smoothly change are generated. The diodes 183 and 184 provide voltage bias.

The first distribution current signal j1 of the first distributor 31.
Changes according to the multiplication result h1 · d1 of the switching signal h1 (inflow current value) and the first output current signal d1 (current value) of the command unit 15. Similarly, the first distribution current signal j2 is the result of multiplication of the switching signal h2 and the first output current signal d1 by h2.
The first distribution current signal j3 changes according to d1, and the first distribution current signal j3 is a multiplication result h3 · d1 of the switching signal h3 and the first output current signal d1.
It changes according to. The combined current value j1 + j2 + j3 of the first distributed current signal is equal to the first output current signal d1.

The switching signal i input to the second distributor 32
1, i2 and i3 are second diodes 200,
A current is made to flow out from 201 and 202, and a voltage signal corresponding to the outflow current value of i1, i2 and i3 is generated. Second
One ends of the diodes 200, 201 and 202 are commonly connected, and the other ends thereof are respectively connected to the second distribution transistor 20.
5, 206 and 207 are connected to respective base terminals. The second output current signal d2 of the command unit 15 is supplied to the commonly connected emitter terminal sides of the second distribution transistors 205, 206 and 207. Therefore, the second distribution transistors 205, 206 and 207 respond to the switching signals i1, i2 and i3, respectively, to output the second output current signal d.
2 is distributed, and three-phase second distribution current signals k1, k2, and k3 (outflow current) that change smoothly are created. The diodes 203 and 204 are applied with voltage bias.

The second distribution current signal k1 of the second distributor 32.
Changes according to the multiplication result i1 · d2 of the switching signal i1 (outflow current value) and the second output current signal d2 (current value) of the command unit 15. Similarly, the second distribution current signal k2 is the multiplication result i2 · of the switching signal i2 and the second output current signal d2.
The second distribution current signal k3 changes according to d2, and the multiplication result i3 · d2 of the switching signal i3 and the second output current signal d2.
It changes according to. The combined current value k1 + k2 + k3 of the second distributed current signal becomes equal to the second output current signal d2.

In FIG. 5, transistors 220 and 221, 222 and 223, and 224 in combiner 33 are shown.
And 225, the three current mirrors invert and output the first distributed current signals j1, j2, and j3, respectively. Transistors 230 and 231, 23 of combiner 33
The three current mirrors 2 and 233, and 234 and 235 respectively have the second distribution current signals k1 and k2.
And k3 are inverted and output. The first distribution current signal j1 and the second distribution current signal k1 are combined at the connection point of the output terminals of the current mirror (the connection point of the collector of the transistor 221 and the collector of the transistor 231), and the difference current (j1-k1) To produce a combined distribution current signal. This combined distribution current signal is supplied to the resistor 241 and produces a distribution signal m1 as a voltage drop across the resistor 241.

Similarly, the first distribution current signal j2 and the second distribution current signal k2 are combined at the connection point of the output terminals of the current mirror to generate a combined distribution current signal corresponding to the difference current (j2-k2). . This combined distribution current signal is resistor 2
42, which produces a distribution signal m2 as a voltage drop across resistor 242. Similarly, the first distribution current signal j3 and the second distribution current signal j3
The distribution current signal k3 is combined at the connection point of the output terminals of the current mirror to generate a combined distribution current signal according to the difference current (j3-k3). This combined distribution current signal is supplied to the resistor 243, which produces the distribution signal m3 as a voltage drop across the resistor 243. In this way, the distribution signal m1,
m2 and m3 are switching signals h1 and i1, h2, respectively.
And i2, and three-phase voltage signals corresponding to h3 and i3, and the amplitude value thereof has a predetermined amplitude determined by the stable current value of the output current signals d1 and d2 of the command unit 15. That is, the amplitude values of the distribution signals m1, m2, and m3 are not affected by the amplitude values of the detection signal and the switching signal.

The driving unit 14 of FIG. 1 is composed of a first driving unit 41, a second driving unit 42 and a third driving unit 43, and drives the distribution signals m1, m2 and m3 from the distribution unit 13 by power amplification. The signals Va, Vb and Vc are supplied to the three-phase coil 1
Supply to the terminals of 1A, 11B and 11C. FIG. 6 illustrates a first driver 41, a second driver 42, and a third driver 41 in the driving unit 14.
6 is a circuit diagram showing a specific configuration of a driver 43. FIG. The distribution signal m1 is input to the non-inverting terminal of the amplifier 260 of the first driver 41, and voltage-amplified by the amplification factor determined by the resistors 261 and 262. The drive signal Va generated by the voltage amplification is supplied to the power supply terminal of the coil 11A.

Similarly, the distribution signal m2 is input to the non-inverting terminal of the amplifier 270 of the second driver 42 and voltage-amplified by the amplification factor determined by the resistors 271 and 272. In this way, the drive signal Vb is generated and supplied to the power supply terminal of the coil 11B. Similarly, the distributed signal m3 is input to the non-inverting terminal of the amplifier 280 of the third driver 43, and the resistors 281 and 28 are connected.
The voltage is amplified with an amplification factor determined by 2. In this way, the drive signal Vc is generated and supplied to the power supply terminal of the coil 11C. The power supply voltages of + Vm (= + 15V) and -Vm (= -15V) are supplied to each of the amplifiers 260, 270, and 280. Three-phase drive currents are applied to the three-phase coils 11A, 11B, and 11C by the drive signals Va, Vb, and Vc, and a driving force in a predetermined direction is generated by electromagnetic action with the field magnet unit 10.

FIG. 7 is a graph showing waveforms relating to the operation of the brushless motor of this embodiment. The horizontal axis of the graph represents the rotational position. The two position detection elements 107a and 107b that detect the magnetic field of the field unit 10 in accordance with the rotation of the field unit 10 (or relative movement with the three-phase coil) detect sinusoidal two-phase detection signals. (E1-e2) and (f1-f2)
Is obtained ((a) of FIG. 7). The switching generator 22 includes a first set of three-phase switching signals h1, h2, and h3 (first diodes 180 to 182) that smoothly change according to the two-phase detection signal.
To the second diode of FIG. 7 and the second set of three-phase switching signals i1, i2 and i3 (current to the second diodes 200-202, FIG. 7C).

The first distributor 31 outputs the signal values of the switching signals h1, h2 and h3 (first diodes 180, 181 and 1).
Current distribution to the first distribution transistor 18
5, 186 and 187 distribute the first output current signal d1 of the command unit 15, and the three-phase first distribution current signal j1
Obtain j2 and j3 ((d) of FIG. 7). The first distribution current signals j1, j2 and j3 are the switching signals h1, h2 and h3.
And the first output current signal d1 multiplied by h1 · d1, h
It is a three-phase current signal distributed such that the added value h1.d1 + h2.d1 + h3.d1 becomes equal to the first output current signal d1 in accordance with 2 · d1 and h3 · d1 respectively. Similarly, the second distributor 32 outputs the switching signals i1, i
The second output current signal d2 of the command unit 15 is distributed by the second distribution transistors 205, 206 and 207 in response to the signal values of 2 and i3 (current values to the second diodes 200, 201 and 202), and 3 Second distributed current signal k of phase
1, k2 and k3 are obtained ((e) of FIG. 7).

The second distributed current signals k1, k2 and k3 are
Switching signals i1, i2 and i3 and second output current signal d2
Depending on the multiplication results i1 · d2, i2 · d2 and i3 · d2, the added value i1 · d2 + i2 · d2 + i3 · d
2 is a three-phase current signal distributed so that 2 becomes equal to the second output current signal d2. The combiner 33 includes the first distribution current signals j1, j2 and j3 and the second distribution current signals k1, k.
2 and k3 are combined to obtain three-phase distribution signals m1, m2, and m3 ((f) in FIG. 7). The distribution signals m1, m2, and m3 correspond to the phase difference currents j1-k1, j2-k2, and j3-k3 of the first distribution current signal and the second distribution current signal, respectively. The first driver 41, the second driver 42, and the third driver 43 of the driving unit 14 have a distribution signal m1 and a distribution signal m1, respectively.
The drive signals Va, Vb and Vc ((g) in FIG. 7) having voltage waveforms corresponding to m2 and m3 are supplied to the three-phase coils 11A, 11B and 11C.

With the configuration of this embodiment, a three-phase switching signal can be created using the two-phase detection signals obtained by the two position detecting elements. In addition, even if the amplitude of the switching signal changes according to the detection signal, the first distributor 31
The first distributed current and the second distributed current by the second distributor 32 are surely limited to the amplitudes corresponding to the first output current signal d1 and the second output current signal d2 of the command unit 15. Therefore,
Distribution signals m1, m2 and m3 (or drive signal Va,
Vb and Vc) are not affected by the amplitudes of the detection signal and the switching signal. That is, the position detecting element 1 of the position detector 21
The influences of the sensitivity variations of 07a and 107b, the magnetic field variations of the field unit 10 and the circuit gain variations of the switching generator 22 are extremely small, and are virtually unaffected.

Therefore, the brushless motor of this embodiment has a simple structure with a small number of parts of the position detection element, and when the brushless motor of this embodiment is used for speed control and torque control, the There is no variation in the speed control gain or the torque control gain in the above, and the motor control performance during mass production becomes extremely stable (the control instability phenomenon due to the variation in the motor gain does not occur). That is, the first
Since the distributor and the second distributor perform the non-linear multiplication and distribution operation, even if the detection signal and the switching signal are distorted or varied, the influence on the drive signal is reduced. In this embodiment, even if the detection signal of the position detector changes in a smooth sine wave shape, the distribution signal and the drive signal are distorted into a trapezoidal wave shape as shown in FIG. Although such a degree of distortion is acceptable in many applications, it is preferable to eliminate the distortion in order to realize a higher performance brushless motor. Next, an example in which this point is improved will be described.

<Embodiment 2> Hereinafter, a second embodiment of the present invention will be described with reference to the drawings. 8 to 11 show the configuration of the brushless motor according to the second embodiment. FIG. 8 is a block diagram showing the overall configuration. The feature of the second embodiment with respect to the first embodiment is that the command unit 15 of FIG. I am doing it. The same parts as in Example 1 are designated by the same reference numerals. FIG. 9 is a circuit diagram showing a specific configuration of the command current unit 301 in the command unit 15.
Transistors 321, 322 and resistors 323, 324
Responds to the command signal R to shunt the current value of the constant current source 320 to the collector side of the transistors 321 and 322, and the collector currents are compared by the current mirror of the transistors 325 and 326. Then, the difference current is output as command current signals p1 and p2 via the current mirrors of the transistors 327, 328 and 329. Therefore, the command current device 301 produces two command current signals p1 and p2 (p1 and p2 are in a proportional relationship) in response to the command signal R, and the first command current signal p1 is supplied to the current combiner 303. Then, the second command current signal p2 is supplied to the multiplication command device 302.

FIG. 10 is a circuit diagram showing a specific configuration of the multiplication command unit 302 of the command unit 15. Transistor 342
And 343 distribute the current value of the constant current source 341 to the collector side in response to the detection signals e1 and e2 of the position detection elements, respectively, and obtain the difference current by the current mirrors of the transistors 344 and 345. The voltage signal s1 corresponding to the absolute value of the difference current is supplied to the transistors 346, 347, 34.
8, 349, 350 and 351, and resistor 411. That is, the voltage signal s1 (absolute value signal) corresponding to the absolute value of the detection signals e1-e2 is created. Similarly, the transistors 362 and 363 distribute the current value of the constant current source 361 to the collector side in response to the detection signals f1 and f2 of the position detecting element, respectively, and the transistors 364 and 36
The difference current is obtained by the current mirror of No. 5, and the transistors 366, 367, 368, 369, 360 and 361 are calculated.
Further, the voltage signal s2 corresponding to the absolute value of this difference current is obtained by the resistor 412. That is, the voltage signal s2 (absolute value signal) corresponding to the absolute value of the detection signals f1-f2 is created.

The transistors 376 and 377 distribute the current value of the constant current source 375 to the collector side in response to the detection signals e1 and e2, respectively, and the transistors 379 and 38.
0 distributes the current value of the constant current source 378 to the collector side in response to the detection signals f1 and f2, respectively. The collector currents of the transistors 377 and 380 are combined, and the combined current is output via the current mirrors of the transistors 381 and 382. And transistor 3
76, the difference current between the combined value of the collector currents of the transistor 379 and the output current of the transistor 382 is obtained, and the voltage signal corresponding to the absolute value of the difference current is obtained by the transistors 386, 387, 388, 389, 390 and 391 and the resistor 413. Get s3. That is, the voltage signal s3 (absolute value signal) corresponding to the absolute value of the combined signal obtained by arithmetically combining the two-phase detection signals e1-e2 and f1-f2 is generated.
Therefore, the voltage signals s1, s2, and s3 are three-phase absolute value signals corresponding to the two-phase detection signals. Also, s
1, s2 and s3 are synchronized with the three-phase switching signals. The current sources 341, 361, 375 and 378 are set to have a predetermined current value.

The transistors 414, 415, 416 and 417 and the diodes 419 and 420 compare the three-phase absolute value signals s1, s2 and s3 with a predetermined voltage value (including 0V) of the constant voltage source 418, and compare the absolute values. The command current signal p2 of the command current generator 301 (FIG. 9) is shunted to each collector side according to the difference voltage. Transistors 414, 415 and 4
The 16 collector currents are combined and the current mirror of transistors 421 and 422 compares the combined current with the collector current of transistor 417. The difference current is output as the multiplication command current signal q via the current mirrors of the transistors 423 and 424 (inflow current).
The multiplication command current signal q corresponds to the multiplication result of the three-phase absolute value signals s1, s2, and s3 corresponding to the detection signal and the command current signal p2 corresponding to the command signal. In particular, due to the configuration of the transistors 414, 415, 416 and 417 and the diodes 419 and 420, the three-phase absolute value signal s
The multiplication command current signal q changes according to the multiplication result of the minimum value of 1, s2 and s3 and the command current signal p2. The minimum value of the three-phase absolute value signals s1, s2, and s3 corresponding to the two-phase detection signal is a harmonic signal that is synchronized with the detection signal and that changes six times with respect to one cycle change of the detection signal. Therefore, the multiplication command current signal q is a harmonic signal having an amplitude proportional to the command current signal p2 and changing 6 times per cycle of the detection signal.

FIG. 11 shows the current combiner 303 in the command unit 15.
3 is a circuit diagram showing a specific configuration of FIG. Multiplication command unit 302
The multiplication command current signal q of
Is input to the current mirror, and its current value is reduced to about 1/2, and then added and synthesized with the first command current signal p1 of the command current unit 301. The resultant combined command current signal is output as two output current signals d1 and d2 via the current mirrors of the transistors 433 and 434 and the current mirrors of the transistors 435, 436 and 437. As a result, the first output current signal d1 of the command unit 15
The second output current signal d2 is a current signal that corresponds to the command signal and that includes a harmonic signal component in a predetermined ratio.
The first output current signal d1 is supplied to the first distributor 31 of the distributor 13 (FIG. 8), and the second output current signal d2 is supplied to the second distributor 32.

The position section 12 (position detector 21 and switching generator 22), distributor 13 (first distributor 31, second distributor 32 and combiner 33) and driver 14 (first driver) of FIG. 41, the second driver 42, and the third driver 43) have the same specific configurations and operations as those shown in FIGS. 4, 5, and 6, and detailed description thereof will be omitted. .

FIG. 12 is a graph showing the waveform of each signal in this embodiment. The horizontal axis of the graph represents the rotational position. The position detection elements 107a and 107b that detect the magnetic field of the field unit 10 in accordance with the rotation of the field unit 10 (FIG. 8) (or relative movement with the three-phase coil) detect two-phase sinusoidal waves. The signals e1-e2 and f1-f2 are obtained (see (a) of FIG. 12). Command signal R of predetermined value ((b) of FIG. 12)
On the other hand, the first output current signal d1 and the second output current signal d2 of the command unit 15 are harmonic signal components corresponding to the detection signal due to the operations of the multiplication command unit 302 and the current combiner 303 of the command unit 15. Is included in a predetermined ratio ((c) of FIG. 12). The switching generator 22 generates three-phase switching signals h1, h2, and h3 and i1, i2, and i3 that smoothly change according to the two-phase detection signal. The first distributor 31 is
In response to the signal values of the switching signals h1, h2, and h3 (current values to the first diodes 180, 181, and 182), the first signals are generated.
The first output current signal d1 of the command unit 15 is distributed by the distribution transistors 185, 186 and 187 to obtain three-phase first distribution current signals j1, j2 and j3 ((d) of FIG. 12).

The first distributed current signals j1, j2 and j3 are
The switching signals h1, h2 and h3 and the first output current signal d1
According to the multiplication results h1 · d1, h2 · d1 and h3 · d1, respectively, the added value h1 · d1 + h2 · d1 +
h3 · d1 is a current signal distributed such that it becomes equal to the first output current signal d1. Similarly, the second distributor 32
Is a second output current signal of the command unit 15 by the second distribution transistors 205, 206 and 207 in response to the signal values (current values to the second diodes 200, 201 and 202) of the switching signals i1, i2 and i3. d2 is distributed to obtain three-phase second distributed current signals k1, k2, and k3 (see FIG. 12).
(E)). The second distributed current signals k1, k2 and k3 are
Switching signals i1, i2 and i3 and second output current signal d2
Depending on the multiplication results i1 · d2, i2 · d2 and i3 · d2, the added value i1 · d2 + i2 · d2 + i3 · d
2 is a current signal distributed such that 2 is equal to the second output current signal d2.

The combiner 33 includes the first distribution current signals j1 and j.
2 and j3 and the second distribution current signals k1, k2 and k3 are combined to obtain three-phase distribution signals m1, m2 and m3 (FIG. 12 (f)). The distribution signals m1, m2, and m3 are the difference current j1 for each phase of the first distribution current signal and the second distribution current signal.
The signals correspond to −k1, j2-k2, and j3-k3, respectively. The first driver 41 and the second driver 4 of the driving unit 14
The second and third drivers 43 respectively distribute the distribution signals m1 and m2.
Drive signals Va and Vb having voltage waveforms obtained by power-amplifying m3 and m3
And Vc ((g) in FIG. 12) are three-phase coils 11A, 11
B and 11C.

With the configuration of this embodiment, the three-phase distribution signal m1 generated by using the two-phase detection signals,
m2 and m3 (or drive signals Va, Vb and Vc)
Is the position detection elements 107a and 107 of the position detector 21.
It is no longer influenced by the sensitivity variation of b, the magnetic field variation of the field unit 10 and the circuit gain variation of the switching generator 22 (the influence becomes extremely small), and the amplitude is limited according to the command signal. Further, in the command section, an output current signal proportional to the command signal and containing a harmonic signal component corresponding to the harmonic signal of the detection signal at a predetermined ratio is generated, and this output current and the switching signal (depending on the detection signal Signal), if a distribution signal corresponding to the result of multiplication with
2 and m3 (or drive signals Va, Vb and Vc)
Can be a sinusoidal three-phase signal that changes smoothly according to the detection signal.

Therefore, the distortion of the distribution signal and the drive signal is significantly reduced, and a uniform torque can be obtained to drive the motor smoothly. At this time, the command current generator creates two command current signals according to the command signal, and the multiplication command device creates a multiplication command current signal by multiplying one of the command current signals and the harmonic signal of the detection signal, and the current combiner. If an output current signal obtained by combining the other command current signal and the multiplication command current signal is obtained by, the amplitude fluctuation of the multiplication command current signal can be reduced even if the amplitude fluctuation of the detection signal (and the harmonic signal) occurs (the multiplication command In this case, the transistors 414, 415, and 416 perform a non-linear differential operation), and variations in the ratio of the harmonic signal components included in the output current signals d1 and d2 of the command unit can be reduced. In other words, the structure is strong against variations in the sensitivity of the position detection element and variations in the magnetic field of the field unit. Further, as shown in the present embodiment, if the three-phase absolute value signal corresponding to the detection signal is obtained and the harmonic signal corresponding to the minimum value of the three-phase absolute value signal is obtained, the With a simple configuration, it is possible to accurately generate a harmonic signal that changes 6 times per cycle in synchronization with the detection signal.

<< Embodiment 3 >> A third embodiment of the present invention will be described below with reference to the drawings. 13 to 21
A brushless motor according to the third embodiment is shown in FIG. In this embodiment, the mounting position relationship between the coil and the position detecting element is shifted by an electrical angle of about 30 degrees, and the detecting element is arranged between the coils to facilitate the making of the motor.
Note that the phase relationship between the position detection element and the coil is 3 in electrical angle.
Since they are arranged so as to be shifted by 0 degree, the drive signal shifted by 30 degrees from the detection signal of the position detection element is applied to the coil. FIG. 13 is a block diagram showing the overall configuration. The field unit 510 of FIG. 13 is attached to a rotor or a moving body, forms a plurality of field magnetic poles by the magnetic flux generated by the permanent magnet magnetic poles, and generates the field magnetic flux. The three-phase coils 511A, 511B, and 511C are attached to a stator or a fixed body, and are electrically at a predetermined angle (corresponding to 120 degrees) with respect to the linkage with the magnetic flux generated by the field unit 510.
They are arranged in a staggered manner.

FIG. 14 is a diagram showing a specific structure of the field portion 510 and the three-phase coils 511A, 511B, 511C and the like. An annular permanent magnet 602 attached to the inside of the rotor 601 has its inner surface magnetized to have four poles, and forms a field portion 510 in FIG. Permanent magnet 6
The armature core 603 is provided at the stator position opposite to the magnetic pole 02.
Is arranged. The armature core 603 is provided with three salient pole portions 604a, 604b and 604c at 120-degree intervals, and each salient pole portion has three-phase coils 511A, 51
1B and 511C are salient pole portions 604a, 604b and 6 respectively.
It is wound on each of 04c. Coils 605a, 6
05b and 605c are electrically provided with a phase difference of 120 degrees with respect to the interlinkage magnetic flux from the permanent magnet 602 (one set of N pole and S pole corresponds to 360 degrees of electrical angle). The stator has two position detecting elements 607a and 607a.
07b (for example, a Hall element that is a magnetoelectric conversion element is used) is arranged to detect the magnetic pole of the permanent magnet 602, thereby obtaining a three-phase detection signal corresponding to the relative position of the field magnet and the coil. ing. In this embodiment, the phase between the center of the coil and the center of the position detecting element is shifted by 120 electrical degrees. Accordingly, each position detecting element can be arranged in each winding groove portion of the armature core so as to detect the magnetic field of the inner surface portion of the permanent magnet, and the motor structure can be made compact.

The command unit 515 shown in FIG.
1, a multiplication command unit 552 and a current combiner 553, and produces an output current signal containing a harmonic signal component corresponding to the harmonic component of the detection signal in a predetermined ratio. FIG.
9 is a circuit diagram showing a specific configuration of the command current unit 551 in the command unit 515. The transistors 821 and 822 and the resistors 823 and 824 respond to the command signal R to shunt the current value of the constant current source 820 to the collector side of the transistors 821 and 822, and the collector currents are compared by the current mirrors of the transistors 825 and 826. The difference current is output as command current signals P1 and P2 via the current mirrors of the transistors 827, 828 and 829. Therefore, the command current device 551 produces two command current signals P1 and P2 (P1 and P2 are proportional to the command signal R) corresponding to the command signal R, and the first command current signal P1 is the current combiner 553. And the second command current signal P2 is supplied to the multiplication command unit 552.

FIG. 20 shows the multiplication command unit 552 of the command unit 515.
The following shows a specific configuration. Transistors 842 and 843
Respectively distribute the current value of the constant current source 841 to the collector side in response to the detection signals E1 and E2 of the position detecting element, obtain the difference current by the current mirror of the transistors 844 and 845, and obtain the transistors 846, 847, 848,
A voltage signal S1 corresponding to the absolute value of the difference current is obtained by 849, 850 and 851 and the resistor 911. That is, the voltage signal S1 (absolute value signal) corresponding to the absolute value of the detection signals E1-E2 is generated. Similarly, the transistors 862 and 863 respectively detect the detection signals F1 and F2 of the position detecting element.
In response to the current, the current value of the constant current source 861 is distributed to the collector side, and the difference current is obtained by the current mirror of the transistors 864 and 865.
68, 869, 860 and 861 and the resistor 912 provide the voltage signal S2 corresponding to the absolute value of the difference current. That is, the voltage signal S2 (absolute value signal) that responds to the absolute value of the detection signals F1-F2 is created.

Further, the transistors 876 and 877 are responsive to the detection signals E1 and E2, respectively, to generate a constant current source 87.
The current value of 5 is distributed to the collector side, and the transistor 879
And 880 distribute the current value of the constant current source 878 to the collector side in response to the detection signals F1 and F2, respectively. The collector currents of the transistors 877 and 880 are combined, and the combined current is output via the current mirrors of the transistors 881 and 882. Then, the difference current between the combined value of the collector currents of the transistors 876 and 879 and the output current of the transistor 882 is obtained, and the transistors 886, 887, 888, 889, 8 are obtained.
The voltage signal S3 corresponding to the absolute value of the difference current is obtained by 90 and 891 and the resistor 913.

That is, the voltage signal S3 (absolute value signal) corresponding to the absolute value of the combined signal obtained by arithmetically combining the two-phase detection signals E1-E2 and F1-F2 is produced. Therefore, the voltage signals S1, S2, and S3 are three-phase absolute value signals corresponding to the two-phase detection signals. Also, S1, S2 and S3
Are synchronized with the three-phase switching signals. The current source 84
1, 861, 875 and 878 are set to predetermined current values. Transistors 914, 915, 916 and 9
The 17 and the diodes 919 and 920 compare the three-phase absolute value signals S1, S2, and S3 with a predetermined voltage value (including 0 V) of the constant voltage source 918, and respond to the difference voltage of the command current unit 551. The command current signal P2 is shunted to each collector side.

The collector currents of transistors 914, 915 and 916 are combined to form transistors 921 and 92.
2 current mirror and combined current and transistor 9
The collector current of 17 is compared, and the difference current is halved by the current mirror of the transistors 923 and 924 and output as the multiplication command current signal Q (inflow current). The multiplication command current signal Q corresponds to the multiplication result of the voltage signals S1, S2 and S3 corresponding to the detection signal and the command current signal P2 corresponding to the command signal. In particular, due to the configuration of the transistors 914, 915, 916 and 917 and the diodes 919 and 920, the three-phase absolute value signal S
The multiplication command current signal Q changes according to the multiplication result of the command current signal P2 and the minimum value of 1, S2 and S3. The minimum value of the three-phase absolute value signals S1, S2, and S3 corresponding to the two-phase detection signal is a harmonic signal that is synchronized with the detection signal and changes six times with respect to a change in one cycle of the detection signal. Therefore, the multiplication command current signal Q is a harmonic signal having an amplitude proportional to the command current signal P2 and changing 6 times per cycle of the detection signal.

FIG. 21 shows the current combiner 553 in the command unit 15.
3 is a circuit diagram showing a specific configuration of FIG. Multiplication command unit 552
The multiplication command current signal Q in FIG. 13 is the transistor 931.
And the current mirror 932, and the first command current signal P of the command current device 551 after the current direction is reversed.
It is additively combined with 1. The resultant combined command current signal is output as two output current signals D1 and D2 via the current mirrors of the transistors 933 and 934 and the current mirrors of the transistors 935, 936 and 937. Accordingly, the first output current signal D of the command unit 515
The 1st and 2nd output current signal D2 respond | corresponds to the command signal,
In addition, it becomes a current signal containing a harmonic signal component in a predetermined ratio. The first output current signal D1 is supplied to the first distributor 531 of the distributor 513, and the second output current signal D2 is supplied to the second distributor 532.

The position portion 512 of FIG. 13 is the position detector 52.
1 and the switching generator 522, and 3 from the two-phase detection signals of the position detecting element which constitutes the position detector 521.
A phase switching signal is generated, and the first distributor 5 of the distributor 513
31 and the second distributor 532. FIG. 15 is a circuit diagram showing a specific configuration of the position detector 521 and the switching generator 522. The two position detection elements 607a and 607b forming the position detector 521 are connected in parallel to each other and are supplied with a voltage via the resistor 631. Differential detection signals E1 and E2 corresponding to the detection magnetic field of the field unit 510 (corresponding to the permanent magnet 602 in FIG. 14) are output to the output terminal of the position detection element 607a (E1 and E2 are opposite to each other. It changes depending on the phase.), And is supplied to the bases of the differential transistors 641 and 642 of the switching generator 522 and the bases of the differential transistors 661 and 662.

Differential detection signals F1 and F2 corresponding to the detection magnetic field are output to the output terminal of the position detection element 607b, and the differential transistors 651 and 6 of the switching generator 522 are output.
52 base and differential transistors 664 and 665
Is supplied to the base. Two position detection elements 607
a and 607b have a phase difference of 120 degrees electrically 2
The phase detection signals E1 and F1 (and E2 and F2) are output, and the two-phase detection signals E1 and F1 smoothly change into a sine wave shape or a substantially sine wave shape as the field magnet 510 rotates. Since the detection signals E1 and E2 or F1 and F2 are in opposite phase to each other, the number of substantially independent phases is two in terms of handling.

Constant current sources 640 and 65 of the switching generator 522
Reference numerals 0, 660 and 663 are constant current sources that flow the same constant current. Differential transistors 641 and 642
Distributes the current value of the constant current source 640 to the collector side in response to the detection signals E1 and E2, respectively. The collector currents of the transistors 641 and 642 are the same as the transistor 643.
And 644 current mirrors and outputs the difference current as a switching signal H1. Similarly, the differential transistors 651 and 652 distribute the current value of the constant current source 650 to the collector side in response to the detection signals F1 and F2, respectively. The collector currents of the transistors 651 and 652 are compared by the current mirrors of the transistors 653 and 654, and the difference current is output as the switching signal H2.

The differential transistors 661 and 662 distribute the current value of the constant current source 660 to the collector side in response to the detection signals E1 and E2, respectively.
And 665 respond to the detection signals F1 and F2, respectively, and distribute the current value of the constant current source 663 to the collector side. The collector currents of the transistors 662 and 665 are combined and output through the current mirrors of the transistors 666 and 667. The combined current of the collector currents of the transistors 661 and 664 is compared with the output current of the transistor 667, and the difference current is output as the switching signal H3. The current sources 640 and 65
0, 660 and 663 are set to predetermined current values.

The switching signals H1, H2, and H3 are three-phase current signals (switching current signals) that smoothly change according to the two-phase detection signals, and the first distributor 531 and the second distributor 531 shown in FIG. 532. The first distributor 531 of the distributor 513 of FIG. 13 uses the switching signals H1 and H of the switching generator 522.
In response to 2 and H3, the three-phase first distribution current signal obtained by distributing the first output current signal D1 is obtained. The second distributor 532 responds to the switching signals H1, H2, and H3 of the switching generator 522 to obtain the three-phase second distributed current signal which is the distribution of the second output current signal D2. The combiner 533 combines the first distributed current signal and the second distributed current signal to generate a three-phase distributed signal,
It is supplied to the driving unit 514.

FIG. 16 shows the first distributor 531 of the distributor 513.
A specific configuration of the second distributor 532 is shown. Switching signal H
The currents on the inflow side of 1, H2 and H3 respectively flow into the first diodes 680, 681 and 682 of the first distributor 531 and the inflow current values of H1, H2 and H3 to the terminals of these diodes 680 to 682, respectively. Generates a voltage signal corresponding to. First diodes 680, 681 and 6
One end of 82 is commonly connected, and the other end (current inflow side) is connected to the base terminal sides of the first distribution transistors 685, 686 and 687, respectively. The transistor 683 applies a bias of a predetermined voltage to the first diode. The first output current signal D1 of the command unit 515 is the transistor 6
It is supplied to the commonly connected emitter terminal sides of the first distribution transistors 685, 686 and 687 via the current mirrors 88 and 689. Therefore, the first distribution transistors 685, 686 and 687 have switching signals H1 and H6.
2 and H3 first diodes 680, 681 and 682
The first output current signal D1 is distributed according to the inflow current value into the three-phase first distribution current signal J1, J
2 and J3 (inflow current).

The first distribution current signal J1 of the first distributor 531
Changes according to the multiplication result H1P · D1 of the inflow side current value H1P of the switching signal H1 (current flowing into the first diode 680) and the first output current signal D1 (current value) of the command unit 515. The first distribution current signal J2 changes according to the multiplication result H2P · D1 of the inflow side current value H2P of the switching signal H2 and the first output current signal D1, and the first distribution current signal J3 changes to the inflow side of the switching signal H3. It changes according to the multiplication result H3P · D1 of the current value H3P and the first output current signal D1 (however, the combined current value J1 + J2 + J3 of the first distribution current signal becomes equal to the first output current signal D1).

The outflow side currents of the switching signals H1, H2 and H3 are the second diodes 700 and 701 of the second distributor 532.
And 702 to generate voltage signals corresponding to the current values of H1, H2 and H3 at the terminals of the second diodes 700, 701 and 702. Second diode 700, 70
One ends of 1 and 702 are commonly connected, and the other ends (current outflow side) are connected to the base terminal sides of the second distribution transistors 705, 706, and 707, respectively. The transistor 703 applies a bias of a predetermined voltage to the second diode. The second output current signal D2 of the command unit 515 is supplied to the commonly connected emitter terminal sides of the second distribution transistors 705, 706 and 707. Therefore, the second distribution transistors 705, 706 and 707 are configured to output the second output current signal D according to the outflow current value of the switching signals H1, H2 and H3 to the second diodes 700, 701 and 702.
2 is distributed to produce smoothly varying three-phase second distribution current signals K1, K2 and K3 (outflow current).

The second distribution current signal K1 of the second distributor 532.
Changes according to the multiplication result H1N · D2 of the outflow side current value H1N of the switching signal H1 (outflow current from the second diode 700) and the second output current signal D2 (current value) of the command unit 515. The second distributed current signal K2 changes according to the multiplication result H2N · D2 of the outflow side current value H2N of the switching signal H2 and the second output current signal D2. The second distribution current signal K3 changes according to the multiplication result H3N · D2 of the outflow side current value H3N of the switching signal H3 and the second output current signal D2 (however, the combined current value K1 + K2 + of the second distribution current signal).
K3 becomes equal to the second output current signal D2. ).

FIG. 17 shows a combiner 533 in the distributor 513.
3 is a circuit diagram showing a specific configuration of FIG. The first distribution current signals J1, J2 and J3 are transmitted to the transistors 710 and 711.
And 712 current mirror and transistor 715,
Current mirrors 716 and 717 and transistor 7
The current is inverted by the current mirrors 20, 721 and 722, respectively. The second distribution current signals K1, K2 and K3 are supplied to the current mirrors of the transistors 725, 726 and 727 and the transistors 730, 731 and 73.
The current is inverted by the current mirror of 2 and the current mirrors of the transistors 735, 736, and 737, respectively.

One of the output ends of these current mirrors is connected for each phase to generate a difference current for each phase. The other output current of these current mirrors is the current mirror of transistors 713 and 714, the current mirror of transistors 718 and 719, the current mirror of transistors 723 and 724, the current mirror of transistors 728 and 729, and the transistor Current mirrors 733 and 734 and transistor 7
After the current is inverted by the current mirrors 38 and 739, the output terminals are connected for each phase to create a difference current for each phase.

The difference current (J1-K1) between J1 and K1,
The difference current (K3-J3) between K3 and J3 is added and combined to create a combined distribution current signal.
1 to generate a distribution signal M1 at the terminals of the resistor 741. Similarly, the difference current between J2 and K2 (J2-K2) and K
The difference current (K1-J1) of 1 and J1 is added and combined to form a combined distribution current signal, the combined distribution current is supplied to the resistor 742, and the distribution signal M2 is created at the terminal of the resistor 742. Similarly, the difference current between J3 and K3 (J3-K3) and K2 and J2
Difference current (K2-J2) is added and combined to create a combined distribution current signal, the combined distribution current is supplied to the resistor 743, and the distribution signal M3 is created at the terminal of the resistor 743.

In this way, the distribution signals M1, M2, and M3 become three-phase voltage signals according to the switching signal, and their amplitude values are determined by the current values of the output current signals D1 and D2 of the command unit 515. Amplitude (not affected by the amplitude value of the switching signal). The driving unit 514 of FIG. 13 includes a first driver 541, a second driver 542, and a third driver 54.
Drive signals Va, Vb, and Vc obtained by power amplification of the distribution signals M1, M2, and M3 of the distribution unit 513 are supplied to the terminals of the three-phase coils 511A, 511B, and 511C, respectively.

FIG. 18 shows the first driver 5 in the driving unit 514.
It is a circuit diagram which shows the concrete structure of 41, the 2nd driver 542, and the 3rd driver 543. The distribution signal M1 is input to the non-inverting terminal of the amplifier 760 of the first driver 541, and the resistance 7
The drive signal Va is generated by voltage amplification with an amplification factor determined by 61 and 762, and is supplied to the power supply terminal of the coil 511A. Similarly, the distribution signal M2 is input to the non-inverting terminal of the amplifier 770 of the second driver 542, and the resistors 771 and 772 are input.
The drive signal Vb is generated by voltage amplification with an amplification factor determined by and is supplied to the power supply terminal of the coil 511B. Similarly, the distribution signal M3 is input to the non-inverting terminal of the amplifier 780 of the third driver 543, voltage-amplified by the amplification factor determined by the resistors 781 and 782 to generate the driving signal Vc, and the coil 511 is generated.
Supply to the power supply terminal of C. Note that the amplifiers 760 and 770
And 780 are + Vm (= 15V) and -Vm (= -1).
The power supply voltage of 5 V) is supplied.

Drive signals of three phases are applied to the three-phase coils 511A, 511B, and 511C by the drive signals Va, Vb, and Vc, and a driving force in a predetermined direction is generated by an electromagnetic action with the field magnet 510. FIG. 22 is a graph showing the waveform of each signal in this example. The horizontal axis represents the rotational position. The position detecting elements 607a and 607b that detect the magnetic field of the field unit 510 according to the rotation of the field unit 510 (or the relative movement with the three-phase coil) change smoothly the two-phase detection signal E1-. E2 and F1-F2 are obtained (see FIG. 22 (a)). The switching generator 522 has a three-phase switching signal H that smoothly changes according to the two-phase detection signal.
1, H2 and H3 (outflow / inflow current, FIG. 22 (b))
To produce

The first distributor 531 has switching signals H1 and H2.
And the positive side signal value of H3 (first diodes 680, 681
And the current flowing into 682), the first output current signal D1 ((c) in FIG. 22) of the command unit 515 is distributed by the first distribution transistors 685, 686 and 687,
Three-phase first distribution current signals J1, J2, and J3 are obtained ((d) of FIG. 22). First distributed current signals J1, J2 and J3
Is the positive side signals H1P and H of the switching signals H1, H2 and H3.
Depending on the multiplication results H1P · D1, H2P · D1 and H3P · D1 of 2P and H3P and the first output current signal D1, the added value H1P · D1 + H2P · D1 + H, respectively.
3P · D1 is a current signal distributed such that it becomes equal to the first output current signal D1.

Similarly, the second distributor 532 outputs the switching signal H
1, H2 and H3 negative side signal values (second diode 70
0, 701, and 702).
The second output current signal D2 of the command unit 515 is distributed by the distribution transistors 705, 706 and 707 to obtain the three-phase second distribution current signals K1, K2 and K3 ((e) in FIG. 22). The second distribution current signals K1, K2 and K3 are the negative signal values H1N and H2N of the switching signals H1, H2 and H3.
And the result H1 of multiplication of H3N and the second output current signal D2
The added value H1N · D2 + H2N · D2 + H3N · D2 is a current signal distributed according to N · D2, H2N · D2 and H3N · D2 so as to be equal to the second output current signal D2. The combiner 533 uses the first distributed current signal J
1, J2 and J3 and the second distributed current signals K1, K2 and K
And 3 are combined to obtain three-phase distribution signals M1, M2, and M3 ((f) in FIG. 22).

The distribution signals M1, M2 and M3 are the difference currents J1-K for the respective phases of the first distribution current signal and the second distribution current signal.
It is produced by synthesizing two phases of 1, J2-K2 and J3-K3. That is, the distribution signal M1 is generated by combining (J1-K1) and (K3-J3),
The distribution signal M2 is generated by combining (J2-K2) and (K1-J1), and the distribution signal M3 is (J3-K3) and (K2).
-J2) and are combined. The first driver 541, the second driver 542, and the third driver 54 of the driving unit 514.
3 supplies drive signals Va, Vb, and Vc ((g) in FIG. 22) obtained by power-amplifying the distribution signals M1, M2, and M3 to the three-phase coils 511A, 511B, and 511C, respectively.

With the configuration of this embodiment, a three-phase switching signal can be generated by using a two-phase detection signal. In addition, three-phase switching signals H1, H2, and H corresponding to the detection signal
Even if there are large and small variations in the amplitude of 3
The first distributed current and the second distributed current by the distributor 531 and the second distributor 532 are the first output current signal D1 of the command unit 515.
And is surely limited to the amplitude corresponding to the second output current signal D2. Therefore, the distribution signals M1, M2 and M3 (or the drive signals Va, Vb and Vc) are not affected by the amplitudes of the detection signal and the switching signal. That is, the position detector 52
The influences of the sensitivity variations of the first position detection elements 607a and 607b, the magnetic field variations of the field unit 510, and the circuit gain variations of the switching generator 522 are extremely small, and are virtually unaffected. Therefore, the brushless motor of this embodiment has a small number of parts of the position detecting element and a simple structure. Further, when speed control or torque control is performed using the brushless motor of this embodiment, there is no change in speed control gain or torque control gain between motors, and motor control performance during mass production becomes extremely stable. (There is no control instability phenomenon due to motor gain variations). That is, since the first distributor and the second distributor perform the non-linear multiplication and distribution operation, even if the detection signal and the switching signal are distorted or varied, the influence on the drive signal is reduced.

Further, according to the configuration of this embodiment, the distribution signals M1, M2 and M3 (or the drive signals Va, Vb and Vc) smoothly change in a sinusoidal shape in accordance with the two-phase detection signals. Therefore, since the distribution signal and the drive signal with less distortion can be obtained, a uniformly generated torque can be obtained and the motor can be smoothly driven. Further, with the configuration of this embodiment, the number of position detecting elements is small and the arrangement is free to some extent. Therefore, the position detecting element can be easily arranged between the salient pole portions of the armature core, and the number of wirings thereof is small, so that the motor structure can be downsized.

Fourth Embodiment Hereinafter, a fourth embodiment of the present invention will be described with reference to the drawings. 23 to 26
FIG. 9 shows a diagram relating to the brushless motor according to the fourth embodiment.
Also in the present embodiment, the mounting position relationship between the coil and the position detection element is shifted by an electrical angle of 30 degrees, and the detection element is arranged between the coils to facilitate the manufacture of the motor. FIG. 23 is a block diagram showing the overall structure. In this embodiment, the switching generator 10 outputs a switching signal that is phase-shifted by about 30 degrees in electrical angle from the detection signal of the position detecting element.
22. The combiner 1033 of the distribution unit 513 does not perform the phase shift. In addition, the command unit 51
The current synthesizer 1053 of No. 5 is configured to subtractively synthesize the command current signal and the multiplication command current signal. The same parts as those in Example 3 described above are designated by the same reference numerals.

FIG. 24 shows the position detector 5 in the position section 512.
21 is a circuit diagram showing a specific configuration of the switching generator 21 and the switching generator 1022. FIG. The position detection elements 607a and 607b of the position detector 521 are connected in parallel with each other, and a voltage is supplied via the resistor 631. Differential detection signals E1 and E2 corresponding to the detection magnetic field of the field unit 510 (the permanent magnet 602 in FIG. 14) are output to the output terminal of the position detection element 607a (E1 and E2 change in opposite phases to each other. .). Differential transistors 1141 and 114 of the switching generator 1022
2 base and differential transistors 1161 and 116
It is supplied to the base of 2. Differential detection signals F1 and F2 corresponding to the detection magnetic field are output to the output terminal of the position detection element 607b, and the differential transistors 1151 and 11 are output.
52 base and differential transistors 1164 and 11
Supplied to 65 bases.

Two position detecting elements 607a and 607b
Outputs two-phase detection signals E1 and F1 (and E2 and F2) electrically having a phase difference of 120 degrees from each other, and these two-phase detection signals E1 and F1 are accompanied by the rotational movement of the field unit 510. It changes smoothly. The constant current sources 1140, 1150, 1160 and 1063 of the switching generator 1022 are
It is a constant current source that flows the same constant current. The differential transistors 1141 and 1142 distribute the current value of the constant current source 1140 to the collector side according to the detection signals E1 and E2, and the differential transistors 1151 and 1152 respond to the detection signals F1 and F2, respectively. The current value of is distributed to the collector side. Differential transistor 11
61 and 1162 distribute the current value of the constant current source 1160 to the collector side according to the detection signals E1 and E2,
The differential transistors 1164 and 1165 distribute the current value of the constant current source 1163 to the collector side according to the detection signals F1 and F2, respectively.

Transistors 1141, 1161 and 11
The 64 collector currents are combined, and the combined current and constant current source 1
The current difference with respect to 146 is inverted and output by the current mirror of the transistors 1143, 1144 and 1145.
The collector currents of the transistors 1151 and 1142 are combined, and the combined current is inverted and output by the current mirror of the transistors 1153, 1154 and 1155.
The collector currents of the transistors 1152, 1162 and 1165 are combined, and the difference current between the combined current and the constant current source 1169 is inverted and output by the current mirror of the transistors 1166, 1167 and 1168.

Transistors 1144, 1154 and 11
The output currents of 67 are combined to form transistors 1171, 1
The current mirrors 172, 1173, and 1174 output a current with the combined current reduced to about 1/3. The difference current between the transistors 1145 and 1172 is the switching signal H1.
It is output as (outflow / inflow current). Similarly, the difference current between the transistors 1155 and 1173 is output as the switching signal H2 (outflow / inflow current). Similarly, the difference current between the transistors 1168 and 1174 is output as the switching signal H3 (outflow / inflow current). The current source 1146
The current value of each of 1169 and 1169 is ½ of the current value of the current source 1160.

With such a configuration, the three-phase detection signals (E1-E2) and (F1-F2) are arithmetically combined and electrically have a phase difference of 120 degrees or approximately 120 degrees.
Phase switching signals H1, H2 and H3 (switching current signals) are generated, and the switching signals H1, H2 and H3 are signals obtained by shifting the detection signals E1 and F1 by a predetermined phase (about 30 degrees). The first distributor 531 in the distributor 513 of FIG.
Is the first output current signal D1 of the current combiner 1053 in response to the switching signals H1, H2 and H3 of the switching generator 1022.
To obtain a first distributed current signal of three phases. The second distributor 532 responds to the switching signals H1, H2, and H3 of the switching generator 1022 to distribute the second output current signal D2 of the current combiner 1053 to obtain a three-phase second distributed current signal. The combiner 1033 combines the first distribution current signal and the second distribution current signal to generate a three-phase distribution signal, and supplies it to the driving unit 514. The first distributor 531 and the second distributor 532
The specific configuration of is the same as that of FIG.

FIG. 25 shows a combiner 1033 in the distribution unit 513.
3 is a circuit diagram showing a specific configuration of FIG. The first distributed current signals J1, J2 and J3 are transmitted to the transistors 1210 and 12
11 current mirrors and transistors 1212 and 1
The current is inverted by the current mirror 213 and the current mirrors of the transistors 1214 and 1215. The second distributed current signals K1, K2 and K3 are supplied to the current mirrors of the transistors 1220 and 1221 and the current mirrors of the transistors 1222 and 1223.
Currents are respectively inverted by the current mirrors of the transistors 1224 and 1225. The output terminals of these current mirrors are connected for each phase to generate a difference current for each phase.

The difference current (J1-K1) between J1 and K1 is supplied to the resistor 1231 and produces the distribution signal M1 at the terminal of the resistor 1231. Similarly, the difference current between J2 and K2 (J2
-K2) is supplied to the resistor 1232 to generate the distribution signal M2 at the terminals of the resistor 1232. Similarly, the difference current between J3 and K3 (J3-K3) is supplied to the resistor 1233,
The distribution signal M3 is generated at the terminal 33.

The drive unit 514 of FIG. 23 is the first driver 54.
1, the second driver 542 and the third driver 543, and the drive signals Va, Vb and Vc obtained by power amplifying the distribution signals M1, M2 and M3 of the distribution unit 513 are supplied to the three-phase coils 511A, 511B and 511C. Supply to the terminal. The first driver 541 and the second driver 54 of the driving unit 514
The specific configurations of the second and third drivers 543 are shown in FIG.
Since it is the same as that of No. 8, the description is omitted.

FIG. 26 shows the current combiner 10 in the command unit 515.
53 is a circuit diagram showing a specific configuration of 53. FIG. Command current device 5
The first command current signal P1 of 51 and the multiplication command current signal Q of the multiplication command device 552 are combined to create a combined command current signal, and the current mirrors of the transistors 1241 and 1242 and the transistors 1243, 1244 and 1245.
And a current mirror for producing a first output current signal D1 and a second output current signal D2 corresponding to the combined command current signal. Then, the first output current signal D1 is supplied to the first distributor 531 and the second output current signal D2 is supplied to the second distributor 532. The specific configurations of the command current unit 551 and the multiplication command unit 552 in FIG. 23 are the same as those in FIGS.

Also in the configuration of this embodiment, the distribution signals M1, M2 and M3 (or the drive signals Va, Vb and Vc) are not affected by the amplitudes of the detection signal and the switching signal. That is,
Position detectors 607a and 607b of the position detector 521
Variation in sensitivity, the magnetic field variation in the field unit 510, and
It is not affected by the circuit gain variation of the switching generator 1022 (the effect is extremely small). Further, the distribution signals M1, M2 and M3 (or the drive signals Va, Vb and Vc) smoothly change in a sine wave shape according to the detection signal. Therefore, it is possible to obtain a distribution signal and a drive signal with less distortion, obtain a uniform generated torque, and drive the motor smoothly. Furthermore, the number of position detecting elements is small and the degree of freedom in the arrangement is high. By arranging the position detecting elements between the salient pole portions of the armature core, the motor structure can be made compact.

<Fifth Embodiment> A fifth embodiment of the present invention will be described below with reference to the drawings. 27-28
FIG. 14 is a diagram related to a brushless motor according to a fifth embodiment.
FIG. 27 is a block diagram showing the overall structure. In this embodiment, the configurations of the first driver 1341, the second driver 1342, and the third driver 1343 of the drive unit 514 are PWM drive (pulse width modulation drive) to reduce the power consumption of the drive unit 514. There is. The same parts as those in the third embodiment described above are designated by the same reference numerals.

In FIG. 28, the first driver 134 of the driving unit 514 is shown.
Specific configurations of the first, second driver 1342, and third driver 1343 are shown. Comparator 14 of the first driver 1341
Reference numeral 02 compares the triangular wave signal Nt generated by the triangular wave generation circuit 1401 with the distribution signal M1 to generate a PWM signal W1 having a pulse width corresponding to the distribution signal M1. PWM signal W1
Drive transistors 1403 and 140 depending on the level of
4 are complementarily turned on / off, and drive transistors 1403 and 1404 and drive diodes 1405 and 1
A drive signal Va that digitally changes according to the PWM signal W1 by 406 is supplied to the power supply terminal of the coil 511A.

Similarly, the comparator 1412 of the second driver 1342 compares the triangular wave signal Nt generated by the triangular wave generating circuit 1401 with the distribution signal M2, and outputs the distribution signal M2.
A PWM signal W2 having a pulse width corresponding to is generated. PWM
The drive transistors 1413 and 1414 are complementarily turned on / off in accordance with the level of the signal W2 to drive the drive transistors 1413 and 1414 and the drive diode 141.
5 and 1416 supply the drive signal Vb that digitally changes according to the PWM signal W2 to the power supply terminal of the coil 511B. Similarly, the comparator 1422 of the third driver 1343 compares the triangular wave signal Nt generated by the triangular wave generating circuit 1401 with the distribution signal M3, and outputs the distribution signal M3.
A PWM signal W3 having a pulse width corresponding to 3 is produced. PW
The drive transistor 1423 according to the level of the M signal W3
And 1424 are complementarily turned on / off to drive the drive transistors 1423 and 1424 and the drive diode 14.
25 and 1426 supply the drive signal Vc that digitally changes according to the PWM signal W3 to the power supply terminal of the coil 511C.

Thus, the distribution signals M1, M2 and M3 are
Drive signals Va and V having voltage waveforms for PWM operation according to
b and Vc are three-phase coils 511A, 511B and 511
If each is supplied to C, the driving unit 514 (driving transistors 1403, 1404, 1413, 1414, 1
423 and 1424 and drive diodes 1405 and 140
6, 1425, 1426, 1425 and 1426) the power loss is significantly reduced. The configuration and operation of parts other than the first driver 1341, the second driver 1342, and the third driver 1343 of the driving unit 514 shown in FIG. .

Various modifications can be made to the specific configurations of the above-described embodiments. For example, Example 5
The configuration of the drive unit shown in can be used as the drive unit of the first to fourth embodiments. The coils of each phase may be configured by connecting a plurality of coils in series or in parallel. Each coil may be concentrated winding, distributed winding, or an air core coil without a salient pole portion. The three-phase coil is not limited to star connection, but may be delta connection. The position detecting element is not limited to a Hall element or a magnetoelectric conversion element.

The relative relationship between the coil and the position detecting element can be changed in various ways. The phase difference between the position detecting elements is not limited to 120 degrees as long as a three-phase switching signal can be created from two-phase detection signals. The phase shift performed as necessary is not limited to one of the synthesizer and the switching generator, but may be shared by both. Further, it is preferable to use two or less position detecting elements in order to obtain a two-phase detection signal.
The position detector can be used if it has a configuration in which the two-phase detection signals are obtained and the three-phase switching signals are arithmetically combined from the two-phase detection signals.

The structure of the motor structure is not limited to the case where the field magnet portion has a plurality of magnetic pole portions (not limited to four poles), and the field magnetic flux generated by the permanent magnet is linked to the coil. It suffices that the interlinkage magnetic flux to the coil changes as the field part and the coil move relative to each other. For example, a structure may be adopted in which a bias magnetic field is applied by a permanent magnet, and the tooth portion on the field side and the tooth portion at the tip of the salient pole wound with the coil face each other while rotating or moving. Further, the brushless motor is not limited to the rotary type, but may be a linear type brushless motor in which a magnetic field portion or a coil moves linearly.
In addition, various modifications can be made without changing the gist of the present invention, and it goes without saying that those modifications are also included in the present invention.

[0100]

As described above, according to the brushless motor of the present invention, the three-phase switching signal is generated by using the detection signals of only two phases, and the first output current signal in response to the command signal is set to three.
It is distributed to the three-phase first distribution current signal by the phase switching signal,
The second output current signal responsive to the command signal is distributed to the three-phase second distribution current signal by the three-phase switching signal. And
The first distribution current signal and the second distribution current signal are combined to generate a three-phase distribution signal, and a drive signal corresponding to this distribution signal is supplied to the three-phase coils. With this configuration, even if there are variations in the sensitivity of the position detection element and variations in the gain of the processing circuit, the three-phase switching signals are always balanced as a whole, and the three-phase signals are generated when the distribution signal is generated. However, it does not directly affect the amplitude of the distributed signal. Therefore, fluctuations in drive gain in mass-produced brushless motors are extremely small. Further, the number of parts of the position detection element for obtaining the detection signals of only two phases is small, and the motor configuration is simplified.

Further, according to another configuration of the brushless motor of the present invention, a multiplication signal of a predetermined command signal and a harmonic signal which changes 6 times per cycle of the detection signal according to the two-phase detection signal is used. Then, an output current signal proportional to the command signal and containing a harmonic component corresponding to the multiplication signal at a predetermined ratio is generated, and based on this, a three-phase distribution signal and a drive signal are generated. Therefore, the distribution signal and the driving signal have a smooth waveform with less distortion according to the detection signal, and a uniform driving force with less fluctuation can be obtained.

[Brief description of drawings]

FIG. 1 is a block diagram showing an overall configuration according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a structure of a motor in the first embodiment.

FIG. 3 is a specific circuit diagram of a command current generator 50 according to the first embodiment.

FIG. 4 is a specific circuit diagram of the position detector 21 and the switching generator 22 according to the first embodiment.

FIG. 5 is a specific circuit diagram of a first distributor 31, a second distributor 32, and a combiner 33 in the first embodiment.

FIG. 6 is a specific circuit diagram of a first driver 41, a second driver 42, and a third driver 43 in the first embodiment.

FIG. 7 is a diagram showing waveforms of respective signals in the first embodiment.

FIG. 8 is a block diagram showing an overall configuration according to a second embodiment of the present invention.

FIG. 9 is a specific circuit diagram of a command current generator 301 according to a second embodiment.

FIG. 10 is a specific circuit diagram of the multiplication commander 302 according to the second embodiment.

FIG. 11 is a specific circuit diagram of the current combiner 303 according to the second embodiment.

FIG. 12 is a diagram showing the waveform of each signal in the second embodiment.

FIG. 13 is a block diagram showing an overall configuration according to a third embodiment of the present invention.

FIG. 14 is a structural diagram of a motor according to a third embodiment.

FIG. 15 is a specific circuit diagram of the position detector 521 and the switching generator 522 according to the third embodiment.

FIG. 16 is a first distributor 531 and a second distributor in the third embodiment.
It is a concrete circuit diagram of distributor 532.

FIG. 17 is a specific circuit diagram of the combiner 533 according to the third embodiment.

FIG. 18 is a specific circuit diagram of the first driver 541, the second driver 542, and the third driver 543 according to the third embodiment.

FIG. 19 is a specific circuit diagram of a command current generator 551 according to the third embodiment.

FIG. 20 is a specific circuit diagram of a multiplication command unit 552 according to the third embodiment.

FIG. 21 is a specific circuit diagram of the current combiner 553 in the third embodiment.

FIG. 22 is a diagram showing the waveform of each signal in the third embodiment.

FIG. 23 is a block diagram showing an overall configuration according to a fourth embodiment of the present invention.

FIG. 24 is a specific circuit diagram of the position detector 521 and the switching generator 1022 according to the fourth embodiment.

FIG. 25 is a specific circuit diagram of the combiner 1033 according to the fourth embodiment.

FIG. 26 is a specific circuit diagram of the current combiner 1053 according to the fourth embodiment.

FIG. 27 is a block diagram showing an overall configuration according to a fifth embodiment of the present invention.

FIG. 28 is a first driver 1341 and a second driver in the fifth embodiment.
It is a concrete circuit diagram of a driver 1342 and a third driver 1343.

FIG. 29 is a block diagram showing a configuration of a conventional brushless motor.

[Explanation of Codes] 10, 510 Field Magnets 11A, 11B, 11C, 511A, 511B, 511
C 3-phase coil 12, 512 Position part 13, 513 Distributor 14, 514 Drive part 15, 515 Command part 21, 521 Position detector 22, 522, 1022 Switching generator 31, 531 First distributor 32, 532 Second Distributor 33, 533, 1033 Combiner 41, 541, 1341 First driver 42, 542, 1342 Second driver 43, 543, 1343 Third driver 50, 301, 551 Command current device 107a, 107b, 607a, 607b Position detecting element 302, 552 Multiplying command device 303, 553 Current combiner

Claims (14)

[Claims] 1. A field means for generating a magnetic field flux, a three-phase coil interlinking with the field magnetic flux, and a magnetic field means arranged only at two positions electrically different from each other by a predetermined phase. Position detecting means for detecting a relative position with respect to the three-phase coil to obtain two-phase detection signals electrically different in phase, and smoothly changing according to the two-phase detection signals obtained by the position detecting means. Switching generating means for obtaining at least one set of three-phase switching signals, command means for obtaining a current signal according to the command signal, and three-phase switching of the first output current signal of the command means for the switching generating means. Three-phase first that changes smoothly according to the signal
A first distribution means for distributing to a distribution current signal, and a second output of the command means for changing the second output current signal of the three-phase second according to the three-phase switching signal of the switching creating means.
Second distribution means for distributing to the distribution current signal, combining means for combining the first distribution current signal and the second distribution current signal to obtain a three-phase distribution signal, and three-phase obtained by the combining means And a drive means for supplying a drive signal according to the distribution signal of the above to the terminals of the three-phase coil. 2. The first distributing means has three first diodes to which the three-phase switching signals supplied from the switching creating means should be applied, and a base terminal side is connected to one end of the first diode. ,
The emitter terminal side, to which the output current signal of the command means is to be supplied, is connected in common, and the three-phase first terminal
The brushless motor according to claim 1, further comprising: three first distribution transistors that obtain a distribution current signal. 3. The second distributing means has three second diodes to which the three-phase switching signals supplied from the switching creating means should be applied, and a base terminal side is connected to one end of the second diode. ,
The emitter terminal side, to which the output current signal of the command means is to be supplied, is commonly connected, and the three-phase second terminal
The brushless motor according to claim 1, wherein the brushless motor includes three second distribution transistors that obtain a distribution current signal. 4. The first distribution means has three first diodes to which the three-phase switching signals supplied from the switching generation means should be applied, and a base terminal side connected to one end of the first diode. , An emitter terminal side to which the first output current signal of the command means is supplied is commonly connected, and three first distribution transistors for obtaining three-phase first distribution current signals from the collector terminal side are included. The second distributing means is configured such that three second diodes to which a three-phase switching signal to be supplied from the switching creating means is to be applied and one end of the second diode are connected to the base terminal side, The second output current signal of the means is commonly connected to the emitter terminal side thereof, and is configured to include three second distribution transistors for obtaining three-phase second distribution current signals from the collector terminal side, The synthesizing means obtains a difference current of each phase of the first distribution current signal and the second distribution current signal, and three pieces of composite distribution current signals of three phases according to the difference current should be supplied. The brushless motor according to claim 1, wherein the brushless motor comprises: 5. The command means is the position detecting means 2
A harmonic signal corresponding to the phase detection signal is obtained, the command signal and the harmonic signal are multiplied to obtain a current signal containing the harmonic signal component, and a first signal corresponding to the current signal is obtained. 5. The apparatus according to claim 1, further comprising means for supplying the output current signal and the second output current signal to the first distribution means and the second distribution means, respectively. The brushless motor described in. 6. The command unit obtains two command current signals corresponding to the command signals, and a harmonic signal corresponding to the two-phase detection signals of the position detecting unit to obtain the command. A multiplication command unit that obtains a multiplication command current signal by multiplying one of the command current signal of the current unit and the harmonic signal, and a composite command that combines the other command current signal of the command current unit and the multiplication command current signal. Current combining means for obtaining a current signal and outputting a first output current signal and a second output current signal corresponding to the combined command current signal to the first distribution means and the second distribution means, respectively. The brushless motor according to any one of claims 1 to 4, wherein the brushless motor comprises: 7. The commanding means is the position detecting means 2
It is configured to include a multiplication command means for obtaining a multiplication command current signal by multiplying a harmonic signal that changes six times per cycle of the detection signal according to a phase detection signal and one command current signal of the command current means. The brushless motor according to claim 5, wherein the brushless motor is a brushless motor. 8. The absolute value means for obtaining the three-phase absolute value signal corresponding to the two-phase detection signals of the position detecting means and the absolute value means for comparing the three-phase absolute value signals 8. A harmonic wave means for obtaining a harmonic wave signal according to the minimum value of a value signal is included, and a harmonic wave signal which changes 6 times per one cycle of the detection signal is obtained. The brushless motor described in. 9. The synthesizing means obtains a difference current of each phase between a first distribution current signal of the first distributing means and a second distribution current signal of the second distributing means, and obtains a difference for at least two phases. The brushless motor according to any one of claims 1 to 8, wherein a distribution signal obtained by combining currents is produced. 10. The switching creation means is configured to arithmetically combine the two-phase detection signals of the position detection means to generate a three-phase switching signal having a phase difference of substantially 120 degrees electrically. The brushless motor according to claim 1, wherein the brushless motor is a brushless motor. 11. A field means for generating a field magnetic flux, a three-phase coil interlinking with the field magnetic flux, and 2 depending on a relative position between the field means and the three-phase coil.
Position means for obtaining only the phase detection signals and for obtaining at least one set of three-phase switching signals according to the two-phase detection signals; and the detection signals in synchronization with the two-phase detection signals of the position means. An output current signal proportional to the command signal and including a harmonic component corresponding to the multiplication signal in a predetermined ratio is used by using a multiplication signal of a harmonic signal that changes 6 times per cycle and a predetermined command signal. The command means for producing, the distributing means for obtaining a three-phase distribution signal according to the multiplication result of the output current signal of the command means and the three-phase output signal of the position means, and the three-phase distribution signal of the distributing means. A brushless motor comprising: a drive unit that supplies a drive signal having a corresponding voltage waveform to the terminals of the three-phase coil. 12. The commanding means changes six times per cycle of the detection signal according to the command current means for obtaining two command current signals according to the command signal and the two-phase detection signals of the position means. Multiplication command means for obtaining a harmonic signal to obtain a multiplication command current signal obtained by multiplying one of the command current signals of the command current means by the harmonic signal, and the other command current signal of the command current means and the multiplication. The brushless device according to claim 11, further comprising: a current synthesizing unit that obtains a synthetic command current obtained by synthesizing the command current signal and outputs an output current signal corresponding to the synthetic command current signal. motor. 13. The absolute value signal comparing means for comparing the absolute value signal of the three phase with the absolute value signal for obtaining the absolute value signal of the three phases according to the detection signal of the two phases of the position means. 12. The brushless motor according to claim 11, further comprising: a harmonic wave unit that obtains a harmonic wave signal according to the minimum value of. 14. A field means for generating a field magnetic flux, a three-phase coil interlinking with the field magnetic flux, and a magnetic field means arranged only at two positions electrically different from each other by a predetermined phase. Position detecting means for detecting a relative position with respect to the three-phase coil to obtain two-phase detection signals electrically different in phase from each other, and three-phase coils based on the two-phase detection signals obtained by the position detecting means. A switching generation means for generating a switching signal, a command means for outputting a current signal according to a predetermined command signal, and a summation of the output current signals of the command means according to the three-phase switching signals of the switching generation means. And a drive means for supplying a drive signal having a voltage waveform proportional to the distribution current signal to the terminals of the three-phase coil. Brushless model Data.