JP3124499B2 - Composite three-phase stepping motor and method of driving the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite three-phase stepping motor having a function as an actuator for directly driving a transfer drum of a copying machine without using gears and the like, and a driving method of the motor.

[0002]

2. Description of the Related Art A transfer drum of a copying machine or the like is driven by a brushless motor or the like. In this case, for example, a motor having a rotation speed of about 1500 rpm is decelerated by a gear or the like to achieve a speed of 30 rpm.
The rotation speed is about 60 rpm. FIG.
FIG. 1A shows a structure of an inner rotor type three-phase hybrid (hereinafter abbreviated as HB) type stepping motor conventionally used for this kind of application. FIG. 1A is a vertical sectional front view, and FIG. It is YY 'sectional drawing of figure (A). 11A and 11B, reference numeral 11 denotes a stator, 11C denotes a stator winding, 12 denotes a rotor, 12G denotes a permanent magnet, and 13 denotes a rotor shaft. 14a ₁ to 14A ₆ in each stator pole, A ₁ and A ₂ described in each magnetic pole 14a ₁ to 14A _6, B ₁ and B _2, C ₁ and C ₂ are each A-phase, B-phase, C-phase Are shown as a pair of windings. FIG. 7 shows a drive circuit D of the three-phase HB type stepping motor shown in FIG. 6, in which the A-phase winding 11C ₁ , the B-phase winding 11C ₂ , and the C-phase winding 11C ₃
Are connected to driving power supplies (+) and (−) via _six transistors Tr _{1 to} Tr ₆ . Although a base power supply for each of the transistors Tr _{1 to} Tr ₆ is omitted, it is assumed that a predetermined base current is supplied from the power supply. That is, of the six transistors Tr _{1 to} Tr ₆ , for example,
Each of the three upper transistors Tr ₁ , Tr ₃ , and Tr ₅ and one of the three lower transistors Tr ₂ , Tr ₄ , and Tr ₆
By ON one by number, it is possible to flow electric current to two phases of the three-phase windings, for example, the transistor Tr ₁ and Tr ₄ O
When is N is A-phase winding 11C ₁ (+), B-phase winding 11C ₂
Becomes a (-) potential, and the entire sequence is as shown in FIG. FIG. 8 is a time chart showing the operation of the drive circuit of FIG. 7, and FIG. 8A shows each of the transistors Tr _{1 to} T _1.
The currents applied to the base of r ₆ are shown in FIGS.
And (D) shows the current supplied to the respective A-phase winding 11C _1, B-phase winding 11C ₂ and C-phase winding 11C _3.

[0003]

The above-mentioned prior art has the following problems. First, FIG.
In the inner rotor type three-phase HB type stepping motor shown in (A) and (B), when the outer diameter of the motor size is about 60 mm, the resolution 600 (step angle 0.6 °) is the limit. With a higher resolution, the rotor pole teeth (N
This is because, because r) increases, the pole teeth become smaller than the thickness of the magnetic iron plate and cannot be punched by a press. For this reason, even if the transfer drum or the like of the copying machine is directly driven at 30 to 60 rpm with a stepping motor having such a resolution, the rotation unevenness is large, and it is necessary to drive at a high speed to decelerate. Therefore, it is difficult to achieve high image quality and color shift due to backlash of the speed reducer, etc., and there are problems such as color shift.
SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems (problems) of the prior art, and provides a compound three-phase stepping motor having a function as a sensorless actuator capable of reducing rotation unevenness even at low speed, and a driving method of the motor. To provide.

[0004]

In order to solve the above-mentioned problems, a composite three-phase stepping motor according to the first aspect of the present invention projects radially outward and has Ns tips at each end. A stator configured so that a permanent magnet is sandwiched between two stators having 6n stator poles having pole teeth, and disposed on an outer periphery of the 6n stator poles via an air gap. It is made of a substantially annular magnetic material, and has Nr
A rotor having two pole teeth, and excitation windings mounted on each of the magnetic poles over the two stators, wherein the 6n stator magnetic poles have Ns number of poles at each end. The 6n angles formed between the pole teeth at the same position are (60 m / n-θs) degrees and (6 m / n−θs) degrees.
0m / n + θs) degrees are alternately repeated, and the excitation windings are three-phase excitation windings of a total of 3n odd-numbered from any stator poles for 6n stator poles. In addition to being mounted as wires, a total of 3n of the remaining even-numbered stator magnetic poles were configured to be mounted as another three-phase excitation winding. Where θs = (30 / Nr)
Degree or θs = (30 / Nr) an integer multiple of degree, and N
r is the number of rotor teeth, and n, m, and Ns are integers of 1 or more.
Further, when the number of the stator magnetic poles is 12, as described in claim 2, the twelve stator magnetic poles have the Ns
Angles formed between the pole teeth at the same position are (30−θ).
s) degrees and (30 + θs) degrees are alternately repeated, and the excitation windings are arranged in three odd-numbered one-to-three three-phases from any stator poles for twelve stator poles. And the remaining even-numbered stator magnetic poles are mounted as another three-phase excitation winding. In the case where the number of the stator magnetic poles is 6n, the permanent magnet is formed by two stators each having 6n stator magnetic poles having Ns pole teeth at each end. A stator configured to be sandwiched, and a rotor made of a substantially annular magnetic body disposed on the outer periphery of the 6n stator magnetic poles via an air gap and having Nr pole teeth on the inner peripheral side; Excitation windings attached to respective magnetic poles over the two stators. These excitation windings form a set of 3n stator magnetic poles out of the 6n stator magnetic poles. , Wound as a three-phase excitation winding having two sets of
The angle formed between the 3n magnetic poles provided with the three-phase excitation winding is (60 m / n) degrees, and 3n forming two sets of three phases.
The angle formed between the pieces was set to {(60 m / n) -θs} degrees or {(60 m / n) + θs} degrees. Further, the stator magnetic pole may be 12
In the case where the number of poles is 12
A stator configured to sandwich a permanent magnet between two stators having two stator magnetic poles, and a substantially annular magnetic body arranged via an air gap around the outer circumference of the twelve stator magnetic poles. A rotor having Nr pole teeth on the inner peripheral side;
Exciting windings attached to respective magnetic poles over the two stators, and these exciting windings form a set of six stator magnetic poles out of the twelve stator magnetic poles, The three windings are wound as a three-phase excitation winding having two sets, and the angle formed by the six magnetic poles provided with the three-phase excitation winding is 30 degrees, and the six windings forming two sets of three phases are formed. The angle between them is (30-θ
s) degrees or (30 + θs) degrees. According to a fifth aspect of the present invention, in order to drive any one of the above-described composite three-phase stepping motors, two drive circuits for a three-phase stepping motor configured by assembling six transistors in a bridge are used. The two three-phase stepping motor driving circuits may be alternately triggered to drive one composite three-phase stepping motor. Further, as a driving method of a composite three-phase stepping motor in which k sets of three-phase windings are provided in one set of stepping motors in the circumferential direction, a transistor 6
The k three-phase stepping motor driving circuits, each of which is formed by assembling them in a bridge, are sequentially triggered, and the k three-phase stepping motor driving circuits are sequentially triggered. It is (k
The control may be performed so as to be the (+1) th drive circuit for the three-phase stepping motor. Here, k is an integer of 3 or more.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First, the basic principle of the configuration of the present invention will be described. As a direct drive sensorless actuator for reducing rotation unevenness at low speed,
It is sufficient to use a stepping motor having an extremely high resolution (a small step angle). For example, if an encoder that divides one rotation into 4000 is used, this purpose is satisfied, but it is used in a closed loop, so that the encoder is also expensive and the overall cost becomes high. Therefore, a stepping motor that divides one rotation into 4000 may be used. The step angle is obtained at (180 / NrP) degrees. Here, Nr is the number of rotor teeth, and P is the number of phases.
Therefore, it is sufficient to increase both the number of rotor teeth (Nr) and the number of phases (P), but if the motor size is limited, the number of rotor teeth (Nr) is also limited. Further, when the number of phases (P) is increased, there is a problem that the driving circuit becomes expensive.

Accordingly, in the present invention, first, the number of rotor teeth (N
r) to focus on the outer rotor type in order to increase the number of phases (P) with a low-cost driving method.
In order to increase the power consumption, a composite three-phase stepping motor is configured and driven by a composite three-phase driving method. Hereinafter, the present invention will be described in detail according to each embodiment of the present invention. I do. First Embodiment FIG. 1 shows a first embodiment of an outer-rotor combined three-phase stepping motor according to the present invention. FIG. 1A is a longitudinal sectional front view, and FIG. ) Is Y- in FIG.
It is sectional drawing in the Y 'line. In this embodiment, the stator having 12 stator poles shown in FIG. 1 is described in claim 2 and has a general configuration in which 6n stator poles are provided. This is described in claim 1. 1A and 1B, reference numerals 1A and 1B denote first and second stators, and these stators 1A and 1B are formed to have the same width and diameter in the axial direction and the same symmetrical size. Then, the composite stator 1 is configured by sandwiching the permanent magnet 2 in the middle. Reference numeral 3 denotes an excitation winding for the stators 1A and 1B, and reference numeral 4 denotes a rotor. The exciting winding 3 is actually wound a plurality of turns as shown in FIG.
Here, a one-turn case is shown in principle. The rotor 4 is a rotor portion 4 disposed outside the stators 1A and 1B.
A, 4B, and this rotor 4 has pole teeth of uniform pitch on its inner periphery as shown in FIG. 1 (B), and its thickness in the axial direction as shown in FIG. 1 (A). It is desirable to dispose them in a circumferential direction in the order of a half of the pole tooth pitch, which is about 1/2. In the present invention, since the outer rotor type is used, the permanent magnet 2 is disposed not on the rotor 4 side but on the stator 1 side, and divides the thickness of the stator 1 into approximately two equal parts in the axial direction. A thin permanent magnet 2 having a shape close to the core shape of the stator 1 is magnetized in the axial direction (the thickness direction of the permanent magnet), and is sandwiched between left and right stators 1A and 1B.
The excitation winding 3 is attached to each magnetic pole so that 1B is excited by the common excitation winding 3. In the present embodiment, the stator has 12 poles as shown in FIG. 1B, and the first and second stators 1 shown in FIG.
A, 1B, these permanent magnets 2
The permanent magnet 2 is formed in substantially the same shape as the core shape of A and 1B, and is magnetized into two poles of N and S in the direction of a rotation axis (not shown). In FIG. 1A, for example, when the stator 1B is S
When a DC exciting current is applied to the exciting winding 3 in a state where the stator 1A is an N pole, the stator on either side of the permanent magnet 2 is strengthened (the permanent magnet 2 and the exciting winding 3 The magnetic flux is in the same direction), and the other stator is weakened (the magnetic fluxes of the permanent magnet 2 and the exciting winding 3 are in opposite directions). As a result, magnetic flux enters the rotor 4 from the strengthened N pole of the stator magnetic pole through the air gap into the rotor 4 which is made of a magnetic material and has a large number of pole teeth on the inner circumference, and the magnetic flux enters the S pole of another strengthened stator magnetic pole. The magnetic flux flows in to form a magnetic path and generate torque.

In the structure shown in FIG. 1B, a pair of magnetic poles (for example, magnetic poles A ₁ and A ₂ ) located at 180 degrees from each other among the 12 stator magnetic poles are point-symmetric. It is connected by one winding to form one phase. Then, a set of three-phase windings is formed by each of the A-phase, B-phase, and C-phase stator magnetic poles to form an A ′ phase, a B ′ phase,
Another three-phase winding is formed by each stator pole of the C 'phase. That is, specifically, the A phase is formed by the stator magnetic poles A ₁ and A ₂ , the B phase is formed by the stator magnetic poles B ₁ and B ₂ , and the stator magnetic poles C ₁ and C _{2 are formed.}
Respectively to form a C phase, and these form a set of three-phase windings. Similarly, the stator poles A ₁ ′ and A ₂ ′ form the A ′ phase, the stator poles B ₁ ′ and B ₂ ′ form the B ′ phase, and the stator poles C ₁ ′ and C ₂ ′ form the C ′ phase. Each of them is formed with another set of 3
A phase winding is formed. That is, one of the twelve magnetic poles
A composite three-phase structure in which one set of three-phase windings is formed by every other six magnetic poles and another set of three-phase windings is formed by the remaining six magnetic poles. It has a set of three-phase windings. At this time, 'the angle formed at the same positions from each other of the pole teeth of (30-θs) of the pole A _1' pole A ₁ and A ₁ and B ₁
Is (30 + θs) degrees, the following angle is (30−θs)
It is provided so that the angle of degrees and (30 + θs) degrees are alternately repeated. Here, θs = (30 / Nr) degrees or (30
/ Nr) degrees. FIG. 1B shows the case of θs = 0.6 degrees as shown in FIG.

As shown in FIG. 3, three-phase driving circuits D and D 'are used as driving circuits for the composite three-phase stepping motor.
Can be driven. A driving method of the composite three-phase stepping motor based on the driving circuit shown in FIG. The drive circuits D and D 'can have the configuration shown in FIG. 7, and their output voltages are also those shown in FIG. In this case, the driving circuit D, 'driver circuit D as a trigger pulse of the transistor Tr ₁ to Tr ₆ that constitutes a is P _1, P _2, the drive circuit D' D is P ₁ ', P _2' trigger pulse as shown by It is desirable to set the phase so that P ₁ ′ is triggered between the trigger pulses P ₁ and P _{2 and} the trigger pulse P ₂ ′ is triggered between the trigger pulses P ₂ and P ₃ (not shown). The operation is possible even if the trigger pulses P and P 'are not always intermediate even if the trigger pulses come alternately. The relationship between the output voltages supplied from the driving circuits D and D 'to the windings A, B and C and A', B 'and C' in FIG. 3 will be described with reference to FIG. The output voltage is the voltage shown in FIGS. 8B, 8C, and 8D,
The output voltage of the driver circuit D 'was delayed respectively 30 degrees with respect to each of these output voltages (between P ₁ and P ₂ is 60 degrees) a relationship.

When the composite three-phase stepping motor of FIG. 1 is driven by the drive circuit of FIG. 3, A, B, C,
A ', B', and C 'are shown in correspondence with the phase numbers of the respective stator magnetic poles shown in FIG. If the driving as only three-phase motor single drive circuit D of FIG. 3 the stepping motor of FIG. 1, the phase switching in the three-phase motor 60 degrees as shown in FIG. 8 (between P ₁ and P ₂₎ Therefore, the step angle is (60 / Nr) degrees. Here, Nr is the number of rotor teeth. Even if this stepping motor is driven by another set of three-phase windings (A ', B', C 'phases) using only the other drive circuit D' in FIG. (60 / Nr) degrees. Accordingly, when this stepping motor is driven by two driving circuits D and D 'shown in FIG. 3, as can be seen from FIG. 1, a set of three-phase motors consisting of phases A, B and C and A', B 'and C''Another set of 3
Since the magnetic pole positions of the phase motor are shifted from each other by θs, if θs = (30 / Nr) degrees is selected, this θs becomes the step angle when switching from the A phase to the A ′ phase, and as described above, θs = (30 / Nr) degrees, which is の of the step angle (60 / Nr) degrees for only three phases. Note that θ
Even if s is selected to be, for example, three times (30 / Nr) degrees, the step angle at which the phase shifts from the A phase to the A 'phase is (30 / Nr) degrees, but the description is omitted. This phase switching is performed by A, B, C phases and A ',
By repeating the B 'and C' phases alternately, the step angle (30
/ Nr) degrees.

Second Embodiment FIG. 1 shows that the A, B, and C phases and the A ', B', and C 'phases are arranged at every other magnetic pole with 12 magnetic poles. A second embodiment of the present invention is shown in FIG. Then, as shown in FIG. 4, the A, B, and C phases are continuously (360 /
12) Adjacent magnetic poles of equal pitch of degree and then (360
/ 12) The A ', B', and C 'phases are arranged so as to be different from each other by -θs or + θs, respectively, from the uniform position of degrees.
The magnetic pole at the position of degree is symmetric. A vertical front view of the stepping motor shown in FIG. 4 is equivalent to FIG. A 12-phase composite three-phase stepping motor according to a second embodiment shown in FIG. In addition,
The stepping motor of the present embodiment also operates at the step angle (30 / Nr) with the drive circuit of FIG. In this case, as shown in FIG. 4, six of the twelve magnetic poles A ₁ , B ₁ , C
₁ and A ₂ , B ₂ , and C ₂ are arranged at opposing positions to form a three-phase winding, and then each of them is similarly to the first embodiment shown in FIG.
The position is made different by θs or + θs, and the remaining 6
The magnetic poles A ₁ ′, B ₁ ′, C ₁ ′ and A ₂ ′, B ₂ ′, C ₂ ′
Are arranged adjacent to each other.

In the second embodiment shown in FIG. 4, the number of magnetic poles of the stator is not limited to 12, but may be 6n (an integer of n ≧ 1). At that time, 1/2 of the 6n
Two sets of three-phase windings are made by n pieces, and the angle between the magnetic poles in the 3n pieces is (60 m / n) degrees, and two sets of 3n windings are formed.
The angle between the pieces may be set to {(60 m / n) -θs} degrees or {(60 m / n) + θs} degrees. The second embodiment, which is represented by the general formula assuming that the number of the stator magnetic poles is 6n, is described in claim 3. Here, m is an arbitrary integer, and θs is (30 / Nr) degrees or an integer multiple thereof. For example, in the example of FIG. 4, n = 2 and 6n = 6 × 2 = 12
And the angle between A ₁ and B ₂ is m = 1 and n = 2 (6
0 m / n) degrees = 30 degrees and the angle (C) formed by the two sets of three phases
_The angle between ₁ and A ₁ ') is {(60 m / n) −θs} degree =
(30-θs) degrees.

FIG. 4 has two sets of three-phase windings represented by 12 poles, but the illustration of the windings is omitted. Although not shown, a composite three-phase stepping motor having 18 poles and three sets of three-phase windings is also possible. FIG. 5 shows the circuit configuration. Although FIG. 5 shows the motor unit with three sets of star connection three-phase windings, three sets of delta connection may be used.
In this case, by sequentially triggering three identical three-phase driving circuits D, D ', D "in FIG. 5, the stepping motor rotates according to the same principle as that of FIG.
Each of the driving circuits D, D ', D "may be the same as the three-phase driving circuit D shown in Fig. 7, and the outputs thereof have the functions shown in Fig. 8, respectively. The driving method of the composite three-phase stepping motor by the three driving circuits shown in FIG. 5 is generalized and constituted by k driving circuits in claim 6. That is, in general, six transistors are used. Using k circuits of FIG. 7 consisting of Tr _{1 to} Tr ₆ ,
The k signals are sequentially triggered, and the first three-phase circuit is triggered at the (k + 1) th time.
A composite three-phase stepping motor having a set of three-phase windings in the circumferential direction can be driven. In this case, the step angle can be reduced to (60 / kNr) degrees and 1 / k for three phases.

The driving method of the composite three-phase stepping motor for driving the three-phase driving circuit shown in FIGS. 3 and 5 as one module is an outer rotor type composite three-phase stepping motor having the structure shown in FIGS. However, the present invention is not limited to this, and can be applied to an inner rotor type composite three-phase stepping motor.

[0014]

Since the present invention is configured as described above,
It has the following excellent effects. (1) Because the outer rotor type is a composite three-phase type with a large magnet area and high torque, the outer rotor type increases the number of rotor teeth (Nr) and the composite three-phase type reduces the cost substantially. The number of phases (P) can be increased. Therefore,
The step angle (180 / NrP) can be reduced,
Even at a low speed of about 30 to 60 rpm as a direct drive motor, rotation unevenness does not occur and a high torque motor can be obtained. For example, as shown in the embodiment,
When a plurality of stator magnetic poles of a six-phase (when P = 6) stepping motor are arranged asymmetrically in relation to the step angle θs to use a composite three-phase stepping motor, the step angle θs becomes (30 / Nr) degrees, the number of phases can be doubled and the step angle can be reduced to １ ／ compared to the normal three-phase (P = 3) phase, and the rotation unevenness at low speed can be reduced accordingly. Can be reduced. For this reason, if this motor is used for driving the transfer drum of a copying machine, printing with high image quality and no color shift can be performed. (2) The drive circuit of the composite three-phase stepping motor is composed of k (2)
), An inexpensive multi-phase drive circuit can be realized, and the step angle can be reduced to 1 / k of the three-phase type.

[Brief description of the drawings]

FIG. 1 shows an outer-rotor combined three-phase stepping motor according to a first embodiment of the present invention, wherein FIG. 1 (A) is a longitudinal sectional front view, and FIG. 1 (B) is FIG. Y-
It is the side view seen from the Y 'direction.

FIG. 2 is a side view showing the fixed magnetic pole of FIG. 1B at θs = 0.6 degrees.

FIG. 3 is a connection diagram of a drive circuit of the composite three-phase stepping motor according to the first embodiment of the present invention.

FIG. 4 is a side view of a 12-pole outer rotor composite three-phase stepping motor according to a second embodiment of the present invention.

FIG. 5 is a connection diagram of a drive circuit of an 18-pole composite three-phase stepping motor.

6A and 6B show a conventional three-phase stepping motor. FIG. 6A is a vertical sectional front view, and FIG.
5 is a sectional view taken along line YY ′ of FIG.

FIG. 7 is a connection diagram showing a prototype of a driving circuit for a three-phase stepping motor used in the driving circuits of the conventional example and the present invention.

8 is a characteristic diagram of each unit used in the drive circuit shown in FIG. 7,
FIG. 3A shows the base current of each of the transistors Tr _{1 to} Tr ₆ , and FIGS. 3B, 3 C and 3 D show the A-phase winding 11 C ₁ and the B-phase winding 11 C, respectively. ₂ and C phase winding 11C
₃ shows the current supplied.

[Explanation of symbols]

1, 1A, 1B: the stator 2: the permanent magnet 3: 3-phase exciting winding 4: rotor _{A 1 ~C 1 A 2 ~C 2} , A 1 '~C 1', A 2 '~C 2' : Stator magnetic pole

Claims (6)

(57) [Claims] A stator configured to sandwich a permanent magnet between two stators radially projecting outward and having 6n stator magnetic poles each having Ns pole teeth at each end; A rotor made of a substantially annular magnetic body disposed on the outer periphery of the 6n stator magnetic poles via an air gap and having Nr pole teeth on the inner peripheral side; And the excitation windings attached to the respective magnetic poles.
6n angles formed between the pole teeth at the position are (60 m / n-θ
s) degree and (60m / n + θs) degree alternately
And the excitation winding is connected to 6n stator poles.
One for every 3n odd-numbered poles from any stator pole
And the remaining even number
Excitation of another three phases for a total of 3n stator poles
An outer-rotor combined three-phase stepping motor characterized by being mounted as a winding . Where θs = (30 / Nr) degrees or θs = (30 / Nr)
Every integer multiple of the number, also, Nr the rotor teeth, n, m, N
s is an integer of 1 or more. 2. A stator configured to sandwich a permanent magnet between two stators having twelve stator magnetic poles projecting radially outward and having Ns pole teeth at each end, A rotor composed of a substantially annular magnetic body disposed on the outer periphery of the twelve stator magnetic poles via an air gap and having Nr pole teeth on the inner peripheral side; An excitation winding attached to each of the magnetic poles. The 12 stator magnetic poles have an angle of (30-θs) degrees formed between Ns pole teeth at the same position and having the same position at each tip. And (30 + θs) degrees are alternately repeated, and the excitation windings are one-phase three-phase excitation windings for a total of six odd-numbered stator windings with respect to twelve stator poles. A total of six even-numbered stator magnetic poles are mounted as wires, and another three-phase excitation winding is provided. Outer rotor type composite form three-phase stepping motor which is characterized by being configured to be worn as a. However, θs = (30 /
(Nr) degrees or θs = (30 / Nr) degrees , which is an integer multiple, Nr is the number of rotor teeth , and Ns is an integer of 1 or more. (3)Project radially outward, Ns pieces at each end
Fixed with 6n stator poles with pole teeth
A stator configured to hold a permanent magnet between the stator, Via an air gap around the outer circumference of the 6n stator poles
It is composed of a substantially annular magnetic body disposed, and Nr
A rotor having pole teeth; Excitation mounted on each pole over the two stators
With windings, These excitation windings are 3n of the 6n stator poles.
Three-phase excitation with two sets of stator magnetic poles
Wound as a winding, Angle formed between 3n magnetic poles provided with the three-phase excitation winding
Is (60 m / n) degrees, 3n forming two sets of three phases
The angle between the two is {(60 m / n) -θs} degrees
Or, it was formed so as to be {(60 m / n) + θs} degrees.
Outer rotor composite three-phase stepper characterized by the following:
Motor. Here, θs is a step angle and θs = (30 /
Nr) degrees or an integral multiple of θs = (30 / Nr) degrees, or
Nr is the number of rotor teeth, n, m, and Ns are integers of 1 or more.
is there. (4)Project radially outward, Ns pieces at each end
Fixed with 12 stator poles with 10 pole teeth
A stator configured to hold a permanent magnet between the stator, Via an air gap around the outer circumference of the 12 stator poles
It is composed of a substantially annular magnetic body disposed, and Nr
A rotor having pole teeth; Excitation mounted on each pole over the two stators
With windings, These excitation windings are 6 out of the 12 stator poles.
Three-phase excitation winding with one set of stator poles and two sets
Wound as a line, The angle formed between the six magnetic poles provided with the three-phase excitation winding is
30 degrees, the formation between the six pairs forming two sets of three phases.
Angle is (30−θs) degree or (30 + θs) degree.
Outer rotor type composite, characterized in that
Three-phase step Ping motor. Where θs is the step angle
And θs = (30 / Nr) degrees or θs = (30 / Nr) degrees
Nr is the number of rotor teeth, Ns is 1 or more
Is an integer. 5. The composite according to claim 1, wherein
In a three-phase stepping motor, a three-phase stepper motor composed of six transistors assembled in a bridge
Two driving circuits for the stepping motor are used.
Trigger the drive circuit for the phase stepping motor alternately
To drive one compound three-phase stepping motor
Of three-phase stepping motor
Drive method. 6. The composite according to claim 1, wherein:
In a three-phase stepping motor, a three-phase stepper motor composed of six transistors assembled in a bridge
Using k driving circuits for the stepping motor, the k 3
Trigger the drive circuit for the phase stepping motor
First 3-phase stepping motor drive circuit, then trigger
The (k + 1) th three-phase stepping motor
The feature is that it is controlled to be a driving circuit for
K sets of three-phase windings in one stepping motor
Of a compound three-phase stepping motor with a peripheral in the circumferential direction
Method. Here, k is an integer of 3 or more.