JP2003189571A - Dc motor with concentrated winding type brush - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve an efficiency of a motor by arranging the relationship among the number of pole pairs, the number of slots, a brush width angle and a wiring method. <P>SOLUTION: A DC motor with a concentrated winding type brush comprises a field magnet 4 having a plurality of pole pairs 5 in which N and S poles are used as one pole pair, a shaft 6, a commutator 7 having a plurality of segments 7a, and an armature 8. Lead wires 10 wound between adjacent slots 9 of the armature 8 constitute the concentrated winding type coil 11. A plurality of brushes 12 are provided so as to be able to be brought into contact with the commutator 7. The segments 7a and the wires 10 are delta-connected, and the number Np of the pole pairs is 2, the number Ns of the slots is 6, and the brush width angle A is set to a value between a maximum value Amax and minimum value Amin to be decided according to formulae: Amax=(360×[2× (greatest common divisor of Np and Ns])/(2×Np×Ns)...(1) and Amin=Amax/2...(2). <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a DC motor with a concentrated winding type brush equipped with a concentrated winding type coil rotor and a brush.

[0002]

2. Description of the Related Art Conventionally, DC has been used as a drive source for various devices.
Motors are widely used. The DC motor has excellent characteristics that it is small in size, has a large driving torque, and can be easily controlled in speed and positioning by an electronic circuit.

Now, the basic structure of the DC motor will be described with reference to FIG. Figure 3.2 and the following explanation are quoted from Figure 3.2 and a part of the explanation in the publication ("Illustrations / Illustrations / All about small motors" by Takashi Mishiro + Tomoshige Sado / Technical Review) Has been done.

In FIG. 12, a DC motor 51 includes a stator 52 and a rotor 53 that rotates in the stator 52. The stator 52 includes a housing 54 also serving as a yoke, and a field magnet 55 arranged inside the housing 54.
Including and Brackets 56 and 5 are provided above and below the housing 54.
Blocked by 7. The field magnet 55 is a magnet that creates a basic magnetic flux. The housing 54 is mainly made of iron and constitutes a magnetic circuit (magnetic field) together with the field magnet 55. A brush 59 connected to the terminal 58 is provided on one of the brackets 56. The rotor 53 has a shaft 60.
And a bearing 61, a commutator 62, and an armature 63 provided on the shaft 60. The armature 63 is provided with a coil 64. The coil 64 is configured by connecting the respective conductor wires wound in the plurality of iron core grooves (slots) 65 of the armature 63. The brush 59 comes into contact with the commutator 62 to cause a current to flow through the coil 64. When the current flows through the coil 64, a rotating force is generated in the armature 63.

Here, as shown in FIG. 12, a "lap winding type (distributed winding type)" in which a conductive wire is wound in a plow shape is often used as the coil 64, but the manufacturing process is simplified. , Adjacent slots 6 from the viewpoints of miniaturization and efficiency.
The "concentrated winding type" in which the conductive wire is wound between 5 is more advantageous.

[0006]

By the way, in the concentrated winding type brush DC motor as described above, the number of poles (number of pole pairs) of N poles and S poles constituting the field magnet 55 and the number of slots are determined depending on the use and size thereof. The number of 65 (the number of slots) is different.
Further, the number and size of the brushes 59 also differ depending on the number of each conductive wire forming the coil 64. Furthermore, each conductor and commutator 6
There are star connection and delta connection as the connection method with 2. Although the relationship between these parameters has not been sorted out until now, the applicant of the present application has examined the relationship between these parameters and found an effective relationship that can surely improve the motor efficiency.

Therefore, the object of the present invention is to calculate the number of pole pairs,
An object of the present invention is to provide a concentrated winding brush DC motor capable of improving motor efficiency by arranging the relationship among the number of slots, brush-related elements, and wiring method.

[0008]

In order to achieve the above object, the invention according to claim 1 includes a stator and a rotor,
The stator includes a field magnet including a plurality of pole pairs each having an N pole and an S pole, and the rotor includes a shaft and a commutator and an armature provided on the shaft. , The commutator is composed of a plurality of segments, the armature includes a plurality of slots, a conductive wire is wound between adjacent slots to provide a concentrated winding type coil, and the commutator can be contacted In a DC motor with concentrated winding type brush equipped with a plurality of energizing brushes provided in, the connection between each segment of the commutator and each lead wire is a delta connection, and the number of pole pairs of the field magnet (Np ) Is 2 and the number of slots (Ns) is an arbitrary natural number, the angle formed by the two tangent lines circumscribing in the width direction of each brush from the center of the shaft axis is defined as the brush width angle (A). Define,
It is intended that the brush width angle (A) is set to a value between the maximum value (Amax) and the minimum value (Amin) determined by the following two equations (1) and (2). Amax = (360 × [the greatest common divisor of 2 × Np and Ns]) / (2 × Np × Ns) (1) Amin = Amax / 2 (2)

According to the structure of the above invention, the brush width angle (A) includes the number of pole pairs (Np), the method of connecting each segment of the commutator and each conductor, and the number of slots (Ns). The motor efficiency varies depending on the brush width angle (A). Here, the brush width angle (A) is the maximum value (Ama
By setting the value between x) and the minimum value (Amin), relatively high motor efficiency can be obtained.

In order to achieve the above object, a second aspect of the present invention includes a stator and a rotor, and the stator includes a field magnet composed of a plurality of pole pairs each having an N pole and an S pole. A rotor includes a shaft, a commutator and an armature provided on the shaft, the commutator includes a plurality of segments, and the armature includes a plurality of slots. A DC motor with a concentrated winding brush, comprising: a concentrated winding type coil having a conductive wire wound between adjacent slots; and a plurality of energizing brushes provided so as to contact the commutator. When the connection between each segment and each conductor is a star connection, the number of pole pairs (Np) of the field magnet is a natural number of 3 or more, and the number of slots (Ns) is an arbitrary natural number, the axis line of the shaft Centered on that The angle formed by two tangent lines circumscribing in the width direction of each brush is defined as the brush width angle (A), and the brush width angle (A) is the maximum value determined by the following two equations (1) and (2). The purpose is to set the value between (Amax) and the minimum value (Amin). Amax = (360 × [the greatest common divisor of 2 × Np and Ns]) / (2 × Np × Ns) (1) Amin = Amax / 2 (2)

According to the configuration of the above invention, the brush width angle (A) includes the number of pole pairs (Np), the method of connecting each segment of the commutator and each conductor, and the number of slots (Ns). The motor efficiency depends on the relationship and the brush width angle (A)
It depends on Here, by setting the brush width angle (A) to a value between the maximum value (Amax) and the minimum value (Amin), relatively high motor efficiency can be obtained.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [First Embodiment] A first embodiment of the DC motor with concentrated winding brush according to the present invention will be described in detail below with reference to the drawings.

The basic structure of the DC motor with brush in the concentrated winding brush DC motor of the present embodiment is basically the same as that shown in FIG. 12 described in the conventional example. FIG. 1 is a plan view showing the main part of the structure of the DC motor with concentrated winding brush according to the present embodiment.

This DC motor with brush includes a stator 1 and a rotor 2. The stator 1 includes a housing 3 also serving as a yoke, and an annular field magnet 4 arranged inside the housing 3. The field magnet 4 has an N pole and an S pole that are adjacent to each other.
It is composed of a plurality of pole pairs 5 each having a pole.

The rotor 2 includes a shaft 6 and a commutator 7 and an armature 8 provided on the shaft 6. The armature 8 is an iron core, includes a plurality of slots (iron core grooves) 9, and a conductive wire 10 is wound between the adjacent slots 9.
A concentrated winding type coil 11 is constituted by the conductors 10.

As shown in FIGS. 1 and 2, the commutator 7 is composed of a plurality of fan-shaped segments 7a in a cylindrical shape. Each segment 7a is separated from each other through the slit 7b. On the end face of the commutator 7, a plurality of brushes 1 for energization are provided.
2 are provided so that they can contact each other. These brushes 12 are supported by a bracket (not shown) that covers the end of the housing 3.

The above is the basic structure of the concentrated winding brush DC motor.

Here, the DC motor of the present embodiment is characterized by the following settings. That is, as shown in FIG. 3, the DC motor of this embodiment has a commutator 7
The connection method between each segment 7a and each conductive wire 10 is delta connection. In this embodiment, the pole pair 5 of the field magnet 4 is
2 (hereinafter, referred to as "pole pair number") Np is "2", and the number of slots 9 (hereinafter referred to as "slot number") Ns is an arbitrary natural number, as shown in FIG. 6
An angle formed by two tangent lines circumscribing the axis L of the brush L in the width direction of each brush 12 is defined as a brush width angle A. This brush width angle A is given by the following two equations (1),
It is set to a value between the maximum value Amax and the minimum value Amin determined in (2). Amax = (360 × [the greatest common divisor of 2 × Np and Ns]) / (2 × Np × Ns) (1) Amin = Amax / 2 (2)

In FIG. 1, since the number of pole pairs Np is "2" and the number of slots Ns is "6" in this embodiment, the maximum value Amax from the equation (1) is Amax = (360 × [The greatest common divisor of 2 × 2 and 6]) / (2 × 2 ×
6) Amax = (360 x 2) / 24 Amax = 30 (unit is "deg"). Therefore, the maximum value Amax is “30 °”. Therefore, from the formula (2), the minimum value Amin is: Amin = Amax / 2 Amin = 30/2 Amin = 15 (unit is "deg"). Therefore, the minimum value Amin is “15 °”.

Therefore, in this embodiment, it is optimal to determine the brush width angle A between "15 and 30 °". Here, as an example, the brush width angle A is set to the maximum value A
6 conductors 10 when set to max "30 °"
The change in voltage is shown in the graph of FIG. In this graph, the coil numbers 1 and 4, the coil numbers 2 and 4, and the coil numbers 3 and 6 shown in FIG. 3 are set as a pair, and the phase of the voltage value changes between the pairs of the coil numbers with a mutual shift. I understand. Under this condition, the number of excitation phases is "2".

FIG. 5 is a graph showing the relationship between the number of pole pairs Np and the motor efficiency by comparing delta connection and star connection. Here, the motor efficiency means the ratio of the output (torque x rotation speed) to the input power of the motor. As is clear from this graph, the motor efficiency is highest in both connection methods before and after the number of pole pairs Np is "3", but when the number of pole pairs Np is "2", it is more than in the star connection. It can be seen that the motor efficiency is higher with the delta connection. For this reason, the number of pole pairs Np is set to "2" in the present embodiment employing the delta connection.

FIG. 6 is a graph showing the relationship between the brush width angle A and the motor efficiency by comparing the delta connection and the star connection. As is clear from this graph, 0 to the maximum value A
It can be seen that in the range of the brush width angle A up to max, the delta connection is generally higher in motor efficiency than the star connection. And in the delta connection, the above two equations (1),
Maximum value Amax of brush width angle A determined by (2)
It can be seen that the motor efficiency becomes relatively high in the range of the value from the minimum value Amin.

In the concentrated winding brush DC motor described above, the brush width angle A is the number of pole pairs Np and the commutator 7.
It can be seen that the motor efficiency changes depending on the brush width angle A, depending on the relationship between the connection method of each segment 7a and each conductive wire 10 and the number of slots Ns. Here, in the case where the number of pole pairs Np is “2” and the connection method is delta connection, and the number of slots Ns is “6”, the brush width angle A is the same as the maximum value Amax of “30”.
“”, And relatively high motor efficiency was obtained. As described above, in the present embodiment, the number of pole pairs Np and the number of slots N
By arranging the relationship among s, the brush width angle A, and the wiring method, the motor efficiency of the concentrated winding brush DC motor can be reliably improved.

[Second Embodiment] Next, a second embodiment of the DC motor with concentrated winding brush according to the present invention will be described in detail with reference to the drawings.

In each of the following embodiments including the present embodiment, the same components as those in the first embodiment are designated by the same reference numerals and the description thereof will be omitted. The points will be mainly explained.

In this embodiment, the DC motor is characterized by the following settings. That is, as shown in FIG. 7, in the DC motor of this embodiment, the connection between each segment 7a of the commutator 7 and each conductive wire 10 is a star connection. In this embodiment, when the number Np of pole pairs of the field magnet 4 is a natural number of 3 or more and the number Ns of slots is an arbitrary natural number, the brush width angle A is determined by the above two equations (1) and (2). It is set to a value between the maximum value Amax and the minimum value Amin.

Specifically, when the number of pole pairs Np is set to "3" and the number of slots Ns is set to "9", the maximum value Amax is calculated from the equation (1) as follows: Amax = (360 × [2 × 3 and 9 Greatest common divisor with]] / (2 × 3 ×
9) Amax = (360 × 3) / 54 Amax = 20 (unit is “deg”). Therefore, the maximum value Amax is “20 °”. Therefore, the minimum value Amin is given by the equation (2) as follows: Amin = Amax / 2 Amin = 20/2 Amin = 10 (unit is "deg"). Therefore, the minimum value Amin is “10 °”.

Therefore, the brush width angle A is "10-20.
In this embodiment, the brush width angle A corresponds to the minimum value Amin of "10".
° ”is set. In FIG. 8, the brush width angle A is "1.
The graph shows the voltage changes of the six conductors 10 when the angle is 0 °. The number of excitation phases alternates between "2" and "3".

From the graph of FIG. 5, it is understood that when the number of pole pairs Np is "3 or more", the motor efficiency is higher in the star connection than in the delta connection. For this reason, in the present embodiment employing the delta connection, the number of pole pairs N
p is set to "3".

FIG. 9 is a graph showing the relationship between the brush width angle A and the motor efficiency (output / input) by comparing delta connection and star connection. As is clear from this graph, the brush width angle A from 0 (zero) to the maximum value Amax
In the range of, the star connection is better than the delta connection,
It can be seen that the motor efficiency is generally high. Then, in the star connection, it can be seen that the motor efficiency becomes highest between the maximum value Amax and the minimum value Amin of the brush width angle A determined by the above two equations (1) and (2).

In the concentrated winding brush DC motor described above, the brush width angle A is determined by the specific relationship between the number of pole pairs Np, the wiring method, and the number of slots Ns, and the motor efficiency is determined by the brush width angle A. You can see that it changes depending on.
Here, in the case where the number of pole pairs Np is "3" and the connection method is star connection, and the number of slots Ns is "9", the brush width angle A is equal to the minimum Amin of "10".
“”, And relatively high motor efficiency was obtained. As described above, in the present embodiment, the number of pole pairs Np and the number of slots N
By arranging the relationship among s, the brush width angle A, and the wiring method, the motor efficiency of the concentrated winding brush DC motor can be reliably improved.

[Third Embodiment] Next, a third embodiment of the DC motor with concentrated winding brush according to the present invention will be described in detail with reference to the drawings.

In this embodiment, the commutator 17 and the brush 22 are different in structure from the above-described embodiments. Figure 10
1 is based on FIG. 1 and FIG. 11 is based on FIG. In this embodiment, the commutator 17 is formed in a cylindrical shape by a plurality of arc-shaped segments 17a.
Each segment 17a is separated from each other via the slit 17b. A plurality of energizing brushes 22 are provided in contact with the outer peripheral surface of the commutator 17. These brushes 22
Are supported by a bracket that covers the end of the housing 3. In this configuration, the brush width angle A is defined as shown in FIG.

Therefore, also in this embodiment, the connection method between each segment 17a of the commutator 17 and each conductive wire 10 is a delta connection or a star connection, and according to the connection method, as in each of the above-described embodiments. The number Np of pole pairs and the number Ns of slots are determined, and the brush width angle A is calculated by the above equation (1),
By determining the value between the maximum value Amax and the minimum value Amin obtained according to (2), it is possible to surely improve the motor efficiency as the concentrated winding brush DC motor, as in each of the above embodiments. it can.

Here, as can be seen from comparison with FIGS. 2 and 11, if the brush width angle A is the same in the two cases, the difference in size between the brush 12 and the brush 22 is
It can be seen that this is due to the difference in the distance from the center of the shaft 6. That is, as shown in FIG. 2, as the brush 12 is brought closer to the shaft 6, the substantial size of the brush 12 becomes smaller, and as shown in FIG.
The substantial size of the brush 22 increases as the distance from the brush 22 increases.
Which one is selected may be appropriately selected depending on the size of the DC motor, the application, and the like.

Here, the reason why the motor efficiency is improved by the configuration of each of the above-described embodiments will be considered below. First, regarding the difference in the optimal connection depending on the number of pole pairs Np, the number of drive switching per rotation of the armature 8 may increase as the number of pole pairs Np increases. For example, comparing "4 poles and 6 slots" with "6 poles and 9 slots", the latter has 1.5 times more drive switching times. In other words, it can be said that the drive cycle becomes shorter as the number of pole pairs Np increases. On the other hand, when considering the optimum drive waveform of the motor, the optimum waveform differs depending on the drive cycle. That is, in the motor having a long drive cycle when the number Np of pole pairs is “2” as in the first embodiment, the motor efficiency is high when the drive is close to a square wave. The number Np of pole pairs is “3 or more” as in the second embodiment.
In a motor having a short drive cycle, it is considered that a waveform having a high voltage in the central portion, that is, a waveform in which the voltage has a maximum value in the central portion and the voltage gradually changes is suitable. It is considered that such a phenomenon is caused by the delay of the current due to the inductance of the coil, but the reason why such a driving waveform is taken against the delay can improve the motor efficiency is currently unknown. Is.

The present invention is not limited to the above-mentioned respective embodiments, and a part of the constitution may be appropriately modified within the scope not departing from the gist of the invention and carried out as follows. it can.

(1) In the first embodiment, the case where the number of slots Ns is set to "6" has been described, but the number of slots Ns can be changed as appropriate. For example, the number of slots Ns can be changed to “5, 7, 8 ...”. Even when the number of slots Ns is changed in this manner, the motor efficiency of the concentrated winding brush DC motor can be reliably improved, as in the first embodiment.

(2) In the second embodiment described above, the number of pole pairs Np is "3" and the number of slots Ns is "9". However, the number of pole pairs Np and the number of slots Ns are appropriately changed. You can also For example, if the number of pole pairs Np is "4,
, 6 ", etc., and the number of slots Ns can be changed to" 9, 10, 11, ... "For each number of pole pairs Np. Thus, the number of pole pairs Np and the number of slots Ns
Even when the above is changed, as in the first embodiment,
The motor efficiency of the concentrated winding brush DC motor can be reliably improved.

[0040]

According to the configuration of the invention described in claim 1,
By arranging the relationships among the number of pole pairs, the number of slots, the brush width angle, and the wiring method, it is possible to reliably improve the motor efficiency of the concentrated winding brush DC motor.

According to the second aspect of the present invention, the motor efficiency of the concentrated winding brush DC motor is ensured by arranging the relationship among the number of pole pairs, the number of slots, the brush width angle, and the wiring method. Can be improved.

[Brief description of drawings]

FIG. 1 relates to the first embodiment and is equipped with a concentrated winding type brush D.
It is a top view which shows the principal part of C motor.

FIG. 2 is a plan view showing a relationship between a commutator and a brush.

FIG. 3 is a circuit diagram showing a delta connection.

FIG. 4 is a graph showing changes in excitation and voltage of each conductive wire.

FIG. 5 is a graph showing the relationship between the number of pole pairs and motor efficiency.

FIG. 6 is a graph showing the relationship between brush width angle and motor efficiency.

FIG. 7 is a circuit diagram showing a star connection according to the second embodiment.

FIG. 8 is a graph showing excitation of each conductor and changes in voltage.

FIG. 9 is a graph showing the relationship between brush width angle and motor efficiency.

FIG. 10 is a plan view showing a main part of a DC motor with concentrated winding brush according to a third embodiment.

FIG. 11 is a plan view showing a relationship between a commutator and a brush.

FIG. 12 is an exploded perspective view showing a structure of a conventional brushed DC motor.

[Explanation of symbols]

1 stator 2 rotor 4 field magnet 5 pole pairs 6 shafts 7 commutator 7a segment 7b slit 8 armature 9 slots 10 conductors 11 coils 12 brushes 17 Commutator 17a segment 17b slit 22 brushes

Claims (2)

[Claims] 1. A stator and a rotor, wherein the stator includes a field magnet including a plurality of pole pairs each having an N pole and an S pole, and the rotor is provided on a shaft and a shaft. A plurality of segments, the armature includes a plurality of slots, and a conductor wire is wound between adjacent slots to perform concentrated winding. In a DC motor with a concentrated winding brush, which is provided with a coil of a mold and a plurality of brushes for energization that are provided so as to be able to contact the commutator, the segments of the commutator and the conductors The connection is a delta connection, and the number of pole pairs (Np) of the field magnet is 2
When the number of slots (Ns) is an arbitrary natural number, the angle formed by two tangent lines circumscribing in the width direction of each brush around the axis of the shaft is defined as a brush width angle (A). The brush width angle (A) is defined and set to a value between the maximum value (Amax) and the minimum value (Amin) determined by the following two equations (1) and (2). DC motor with concentrated winding brush. Amax = (360 × [the greatest common divisor of 2 × Np and Ns]) / (2 × Np × Ns) (1) Amin = Amax / 2 (2) 2. A stator and a rotor, wherein the stator includes a field magnet including a plurality of pole pairs each having an N pole and an S pole, and the rotor is provided on a shaft and on the shaft. A plurality of segments, the armature includes a plurality of slots, and a conductor wire is wound between adjacent slots to perform concentrated winding. In a DC motor with a concentrated winding brush, which is provided with a coil of a mold and a plurality of brushes for energization that are provided so as to be able to contact the commutator, the segments of the commutator and the conductors The connection is a star connection, and the number of pole pairs (Np) of the field magnet is 3
When the number of slots (Ns) is an arbitrary natural number, the angle formed by the two tangent lines circumscribing in the width direction of each brush from the center of the axis of the shaft is the brush width angle ( A), and the brush width angle (A) is set to a value between the maximum value (Amax) and the minimum value (Amin) determined by the following two equations (1) and (2). DC motor with concentrated winding brush featuring. Amax = (360 × [the greatest common divisor of 2 × Np and Ns]) / (2 × Np × Ns) (1) Amin = Amax / 2 (2)