JPH0549197A - Armature winding of brushless motor and winding method - Google Patents

Abstract

PURPOSE:To eliminate cogging torque completely by folding back a coil at one end face of a tubular core whereas passing the coil to the side face of shaft at the opposite end face and winding the coil continuously while rotating the axial supporting core of the tubular core. CONSTITUTION:A core 1 having insulated surface is rotated through a supporting core 4. A coil 3 is passed onto the end face of the core 1 in the arrow direction along an upper guide blade 10 and then passed through the circumferentially opposite face of the core 1 to a part adjacent to the start-of- winding. The coil 3 is then hooked at the edge of a fold-back blade 9 and folded back thus winding the coil sequentially. Since the fold-back blade 9 is fixed, the hooked coil 3 advances in the removing direction as the supporting core 4 rotates. Consequently, the coil 3 is disposed while being arranged on the circumferential face of the core 1. According to the invention, cogging torque can be eliminated completely.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is applied to a DC drive brushless motor and relates to an armature winding of a small motor such as a small fan or a vibrator for a pager having a small starting torque.

[0002]

2. Description of the Related Art An armature winding to which the present invention is applied in a brushless motor forms a spatial ampere-turn distribution of the armature winding having an electric angle of 180 ° ^el or more and one magnetic pole width. The armature coil has a magnetic pole width of 180 ° ^el or less in the ampere-turn distribution of the armature winding. The ampere-turn distribution generated by such an armature winding contains many even-numbered harmonics, especially second-order harmonics, in addition to the basic components corresponding to the magnetic pole pairs. The characteristic of the distribution is that the pole center of the ampere-turn distribution of the fundamental wave and one of the poles of the ampere-turn distribution of the second harmonic match at the pole center.

On the other hand, if the combination of the numbers of poles of the permanent magnets facing the armature winding is used as the rotor, the torque distribution with respect to time is generated between the ampere-turn distribution of the armature winding and the rotor magnet. The torque is synthesized between the same number of poles. That is, the pole of the fundamental wave is the first
If the motor is used and the pole of the second harmonic is used as the second motor, it appears on the torque distribution as a combination of the torques generated by the first motor and the second motor. Therefore, at the dead point of the torque generated on the torque distribution of the first motor (the point where the torque is not generated), the ampere turn distribution of the armature winding and the rotor magnet are supplemented by the torque generated by the second motor. It can be used as a motor by arranging the space.

Usually, such a motor is a two-phase brushless motor, and the two first motors, that is, semiconductor switches substantially connected to the armature windings of the two systems, respectively, reduce the torque of each first motor to a minus value. The section is cut and the positive torque part is taken out alternately, and the second motors of the two systems that are present at the same time are arranged so that the positive part of the torque exists at the dead point of the first motor (National Tech-nical Report Vol26). . No5. Oct.
1980 p.794 Two-phase transistor motor).

As a further simplified motor, a first-phase brushless motor is used as the first motor and the second motor in one system, that is, an armature winding of substantially a single system is reduced by a semiconductor switch. Cut the section.
The permanent magnets corresponding to the third motor that constantly generates positive torque in the negative torque cut section are rotated with the stator side by disposing permanent magnets on the armature side and the rotor side separately from the torque negative section. The purpose can be achieved by adding it to the child side.

In addition, as a constitution of a one-phase brushless motor, a coil constitution in which only a fundamental wave component is contained in an armature winding is used, and instead, a permanent magnet is provided in the third motor with a fundamental wave pole number and The same motor can be made to appear by combining two harmonic poles (for example, combining two poles and four poles).
Composed of the above armature winding that generates the motor of
Further, it goes without saying that a configuration in which the permanent magnet corresponding to the third motor is a composite of the number of fundamental wave poles and the number of second harmonic poles also holds (for example, US Patent 4,775,812 Oct.4.19).
88).

Conventionally, such an armature coil winding is wound in a slot of an iron core, and its winding pitch is wound in a short pitch of 180 ° ^el or less. FIG. 3 (a) illustrates an armature structure of a one-phase brushless motor having a fundamental wave ampere-turn distribution of two poles, where 1 is an iron core, 2 is a slot for accommodating a coil 3, and 3 is one phase. The armature coil is wound at a short pitch of 180 ° ^el or less. Reference numeral 4 denotes a support core, and usually the iron core 1 is formed by laminating a soft polar thin plate on the support core. The coil 3 is accommodated as a coil bundle in the slot by winding irregularly.

FIG. 3B illustrates an armature structure of a two-phase brushless motor having a two-pole structure, which is composed of two systems of armature coils 3-1 and 3-2. Slots 2-1 and 2-2 house two systems of armature coils 3-1 and 3-2. That is, torque is generated between the rotor and the rotor made of permanent magnets that are opposed to each other on the circumference of the iron core 1 shown in the figure to form first and second motors (the rotor is not shown).

[0009]

In FIG. 3 (b), the coil 3-1 is determined by the position of the rotor permanent magnet relative to the armature.
Is selected or the coil 3-2 is selected. This is considered to be a selective combination of the configurations of FIG. The above description is based on the assumption that the gap length between the armature core and the rotor magnet surface is constant. That is, the magnetic resistance does not change. Since there is actually a slot 2 for accommodating the coil, the gap length is not constant and reluctance torque is generated between the coil and the rotor, so that cogging torque is generated.

[0010]

SUMMARY OF THE INVENTION The present invention is a cylindrical armature winding in which the armature winding forms a radial air gap between the armature winding and the rotor magnet, and maintains a uniform length of air gap to generate cogging torque. The purpose is to eliminate all of the above and to automate winding of the armature coil. FIG. 2 exemplifies a one-phase brushless motor, in which an armature coil is composed of a first motor and a second motor, and a third motor is a combination in which permanent magnets having the number of poles of a fundamental wave are arranged in a rotor. Here is an example.

In FIG. 2 (a), 1 is an iron core without slots, 3 is an armature winding according to the present invention, and 4 is a supporting core, and these constitute an armature winding. Reference numeral 5 is a main magnet (first motor and second motor) composed of a fundamental wave pole and a second harmonic pole arranged facing each other on the armature winding circumference, and 6 is on the armature winding circumference. A permanent magnet 7 of an additional motor (third motor) composed of fundamental wave poles arranged facing each other is a cup-shaped rotor yoke, which is fitted to a shaft 8 to rotate.

FIG. 2 (b) shows the torque time distribution, where A is the torque distribution of the first motor, B is the torque distribution of the second motor, and C is the torque of the first motor and the second torque. The torque distribution is a combination of the motor torque, OFF is a section where the current is cut off by a semiconductor switch (not shown) connected to the armature winding, D is the torque distribution of the third motor, and E is the total composition that occurs. It is a torque distribution, and P is a stable stop point of the rotor in a non-excitation state.

According to the present invention, the armature winding in such a two-phase or single-phase brushless motor has a combination of an ampere-turn distribution with a basic pole number and an amper-turn distribution with an even multiple pole number, and has a gap between the rotor magnets facing each other. It is to make the length uniform so that there is no change in the magnetic reluctance.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an explanatory view (a) of winding an armature winding according to an ampere turn distribution configuration of 2 poles and 4 poles according to the present invention, a substantial circuit system diagram of an armature coil (b), and winding development. Figure (c)
Is. In FIG. 1A, the iron core 1 whose surface is insulated is rotated by the support core 4. The coil 3 is passed over the end face of the iron core 1 along the upper guide blade 10 in the direction of the arrow shown in the figure,
Further, it passes through the opposite surface on the circumference of the iron core 1 to reach the portion adjacent to the winding start point. Here, the coil 3 is hung on the cutting edge by the knife blade-shaped folding blade 9, and the coil 3 is folded upward and the winding is repeated sequentially. Since the folding blade 9 is fixed, the coil 3 hooked in accordance with the rotation of the support core 4 is displaced from the cutting edge. Therefore, the coils 3 are arranged in alignment on the peripheral surface of the iron core 1.

FIG. 1 (b) shows the relationship between the tap lead-out of the armature coil and the coil. The inflow of a current from the direction of 0 ° ^el makes the armature winding of a two-pole basic pole configuration. Are distributed. FIG. 1 (c) is a developed view of the armature winding, and the arrows show the relationship between tap extraction and current input / output. Α in the figure
The width from the center of the coil is represented by half of the length (angle) of the coil across the end surface of the iron core 1 in (a). The chain double-dashed line is the center line of the coil group of one circuit from the tap drawing of the coil from 0 ° ^el to 180 ° ^el , and can also be expressed as a substantially concentrated coil of one circuit.

As can be seen from the expanded form of the coil, the pole width of the coil formed by the coil 3 is 180 ° in the trapezoidal portion.
^el from an over-pitch, 180 ° ^el in triangular portions
Since the pitch is shorter, a distribution in which the fundamental wave poles and even wave poles coexist in such an ampere-turn distribution, and one pole center of the even wave poles and the pole center of the fundamental wave poles coincide It has become.

Expressing the relationship between the tap lead-out and the coil in FIG. 1 (b), the operation of one system of the two-system circuit is explained. If a current flows into the system, the armature winding will have a balanced distribution due to the overlap of the ampere-turn distributions of the two systems. Therefore, in the case of a two-phase brushless motor, each system is used as a first-phase coil and a second-phase coil, and the armature winding is switched every 180 ° ^el depending on the arrangement of the rotor permanent magnet space.

Further, in the case of a single-phase brushless motor, it is general to drive it by a self-excited single-phase inverter. Therefore, one of the two system circuits is used as an armature winding, and the other system is used for turning on and off the semiconductor switches of the self-excited single-phase inverter.
It can be used as a coil to obtain an induced voltage due to the rotation of the rotor as a signal of F. In this case, since only a small current flows, mutual interference between the coils can be almost ignored. Furthermore, if the armature coils are used as two parallel systems in the current direction in Fig. 1 (b), the pole pitch width of the ampere turn distribution of the armature will be an equal pitch as the mutual synthesis of each circuit, and even harmonics It can also be used as an ordinary armature winding having no slot.

FIG. 4 shows a mass-production winding machine with a winding arrangement according to FIG. 1 (a). That is, the support core 4 is rotated by the motor 12, and the coil 3 is continuously wound from the peripheral surface of the iron core 1 to the upper end surface thereof by the upper guide blade 10 and the folding blade 9 as the flyer 11 rotates. There is nothing on the rotational trajectory surface of the flyer 11 that straddles its axis of rotation. It is needless to say that the structure of the armature winding of the present invention can cope with the multi-phase of the ampere-turn distribution depending on how to draw out the lead wires.

[0020]

According to the present invention, the armature winding of the brushless motor that combines the ampere-turn distributions of the fundamental wave pole and the even wave pole is automatically wound as a smoothing winding constituted by a uniform air gap without magnetic reluctance change. It can be manufactured with a wire machine.

[Brief description of drawings]

FIG. 1 is an embodiment showing a configuration of an armature winding of the present invention. (a) Perspective view showing the winding state of the coil (b) Explanatory diagram showing the circuit system of the armature coil (c) Winding expansion diagram

FIG. 2 is an example of a brushless motor to which the armature of the present invention is applied. (A) Cross-sectional view of a single-phase brushless motor (b) Time-torque distribution diagram of this motor

FIG. 3 is an explanatory diagram showing an armature winding of a conventional brushless motor. (A) A coil configuration explanatory diagram of a single-phase brushless motor (b) A coil configuration explanatory diagram of a two-phase brushless motor

FIG. 4 is a schematic diagram showing a winding state of a mass-production winding machine for armature windings of the present invention.

[Explanation of symbols]

 1 Iron core 3 Coil 4 Support core 9 Folding blade 10 Upper guide blade 11 Flyer

Claims (2)

[Claims] 1. In an armature of a brushless motor in which a coil is wound on a circumferential surface of a cylindrical iron core, the coil has a folded portion of the coil located on the circumference of one end surface of the cylindrical iron core, and on the other end surface thereof. An armature winding for a brushless motor, which is characterized by forming a polygonal shape passing through the end faces and arranging them so as to be distributed at an equal pitch. 2. In an armature of a brushless motor in which a coil is wound on the peripheral surface of a cylindrical iron core, the coil is folded back on the circumference of one end surface of the tubular core, and the coil is passed on the end surface at the other end surface. According to the method, an armature winding method for a brushless motor is characterized in that the axial core of the cylindrical iron core is continuously wound while being rotated.