JP5502978B2 - DC motor - Google Patents

Description

  The present invention relates to a DC motor.

  2. Description of the Related Art Conventionally, there is a direct current motor including a stator having a plurality of magnetic poles arranged in parallel in the circumferential direction and an armature that faces the stator in the radial direction. The armature includes an armature core having a plurality of teeth (saliency poles) that extend radially, and the armature core includes a plurality of armature cores that pass through slots that are spaces between adjacent teeth in the circumferential direction. Is wound.

  For example, in a DC motor described in Patent Document 1, a plurality of armature coils are wound around an armature core by distributed winding wound so as to straddle a plurality of teeth. Moreover, in the DC motor described in Patent Document 2, the plurality of armature coils are wound around the armature core by concentrated winding that is concentratedly wound for each tooth. In general, a direct current motor having a distributed winding armature coil has a smaller excitation force due to magnetism between the armature core and the magnetic pole than a direct current motor having a concentrated winding armature coil. It is advantageous for reducing noise and vibration. On the other hand, a DC motor having concentrated winding armature coils is advantageous in increasing the output because the space factor of the armature coils is high.

Japanese Patent Laid-Open No. 2007-116813 JP 2004-88915 A

  However, when the armature coil is wound around the armature core with distributed winding, the coil end portion that is a portion protruding in the axial direction from the axial end surface of the armature core in the armature coil overlaps in the axial direction. This increases the size of the DC motor. And if it is going to suppress the axial height of a coil end part in order to suppress the enlargement of a direct-current motor, the number of turns of an armature coil will decrease and the output of a direct-current motor will be caused.

  On the other hand, in a DC motor in which an armature coil is wound in a concentrated manner on the armature core, the difference between the magnetic pole and the teeth (saliency pole) is small, so the fluctuation of the magnetic flux becomes abrupt. When driving, there is a possibility that a large vibration is generated due to an excitation force acting on the armature core.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a DC motor that can suppress an increase in size due to an armature coil and can suppress vibration without reducing output. It is in.

In order to solve the above-mentioned problem, the invention described in claim 1 includes a plurality of magnetic poles arranged in parallel in the circumferential direction and a plurality of teeth arranged in parallel in the circumferential direction. An armature core opposed in the direction, a plurality of armature coils wound around the teeth, and a plurality of segments arranged side by side in the circumferential direction, and commutation provided so as to be integrally rotatable with the armature core And a plurality of power supply brushes that are pressed and contacted with the segments, wherein each of the teeth branches to a tip portion of the DC motor so as to be separated in the circumferential direction to form a forked shape. has a branch tooth portion, a plurality of the armature coils, a plurality of concentrated winding inner layer coils arranged in no circumferential overlap each other in each wound in the radial direction at the base end portion in a concentrated winding of each of the teeth When, than the concentrated winding inner coil And a plurality of distributed winding outer layer coils arranged in no circumferential overlap each other in two of the branches teeth adjacent two of the teeth adjacent in the circumferential side are respectively wound at distributed winding in the radial direction, each The center in the circumferential direction of the concentrated winding inner layer coil and the center in the circumferential direction of each of the distributed outer layer coils are shifted in the circumferential direction, and the commutator has the number of segments twice the number of teeth and the branch. The same number as the teeth portion is provided, and n (n is an even number of 2 or more) of the plurality of segments has one end of the concentrated inner layer coil and one end of the distributed outer layer coil. each is connected to the said segments of the half of the remaining said segment, the ends of two of the concentrated winding inner coil are connected one by one, the said segments of the other half, two of said distributed winding outer layer co End Le is the gist that are connected one by one.

According to this configuration, it distributed winding outer layer coil, because it is wound around the teeth at the outer side of the concentrated winding the inner layer coils do not overlap the concentrated winding inner coil in the axial direction. Therefore, the coil end portions of the concentrated winding inner layer coil and the distributed winding outer layer coil can be prevented from becoming larger in the axial direction, and consequently the axial size increase of the DC motor of the present invention can be suppressed. And since it is not necessary to reduce the number of turns of the concentrated winding inner layer coil and the distributed winding outer layer coil in order to suppress the axial height of the coil end portion, the increase in the axial direction of the DC motor is suppressed without lowering the output. can do. In addition, when the size is the same as that of a conventional DC motor having a distributed winding armature coil, the space factor can be increased by increasing the number of turns of the concentrated winding inner layer coil and the distributed winding outer layer coil. Output can be increased. Furthermore, since the center in the circumferential direction of each concentrated winding inner layer coil and the center in the circumferential direction of each distributed winding outer layer coil are shifted in the circumferential direction, the fluctuation of the magnetic flux compared with a DC motor having a concentrated winding armature coil. Can be relaxed. Therefore, it is possible to suppress vibrations that occur when the DC motor is driven.

In addition, each tooth has a pair of branching teeth portions that are bifurcated by branching away from each other in the circumferential direction, and therefore, a concentrated inner coil is wound around the proximal end portion of the teeth. by winding the distributed winding outer layer coil into two branches teeth circumferentially adjacent to straddle the teeth adjacent to, can be formed easily distributed winding outer layer coils on the outer peripheral side of the concentrated winding inner coil In addition, the center in the circumferential direction of each concentrated winding inner layer coil and the center in the circumferential direction of each distributed winding outer layer coil can be easily shifted in the circumferential direction. In addition, since the concentrated winding inner layer coil is wound by concentrated winding on the base end portion of the teeth, that is, the portion that is not branched, the vicinity of the base end portion of the teeth can have a high space factor.

Moreover, the concentrated winding inner layer coil and the distributed winding outer layer coil can be continuously wound around the armature core by using (n / 2) flyers. When n is 2, by winding a distributed winding outer layer coil after winding all concentrated winding inner layer coils, all in succession in one conductor concentrated winding inner coil and distributed winding outer coil Can be wound around the armature core. On the other hand, when n is 4 or more, a plurality of flyers are simultaneously used to wind a concentrated winding inner layer coil and then a distributed winding outer layer coil, so that each flyer is continuously connected with one conductor. Thus, the concentrated winding inner layer coil and the distributed winding outer layer coil can be wound. When a plurality of flyers are used simultaneously, the time required for winding the concentrated winding inner layer coil and the distributed winding outer layer coil can be shortened, and the productivity of the DC motor can be improved.

According to a second aspect of the present invention, in the direct current motor according to the first aspect, the magnetic pole includes P pieces (P is an even number) and is located at an interval of (360 / (P / 2)) ° (P / 2). One end of the concentrated winding inner layer coil and one end of the distributed winding outer layer coil are connected to two of the plurality of segments one by one through a short-circuit line that short-circuits the segments. Of the remaining segments, one end of two concentrated winding inner layer coils is connected to half of the segments, and one end of two distributed winding outer layer coils is connected to the other half of the segments. This is the gist.

According to this configuration, it is possible to continuously wind all concentrated winding inner layer coils and distributed winding outer layer coils including a short-circuit wire with one conductive wire. And when all the concentrated inner layer coils and distributed outer layer coils including the short circuit wire are continuously wound with one conductive wire, the short circuit wires are continuously generated when the concentrated inner layer coil and distributed outer layer coil are wound. Since it is formed, the number of manufacturing steps is reduced as compared with the case where a short-circuit member is separately formed and arranged. Therefore, the productivity of the DC motor is improved.

According to a third aspect of the present invention, in the DC motor according to the first or second aspect, the commutator includes the segments by an integer multiple of the number of the magnetic poles, and the armature cores are adjacent to each other. An inner slot through which the concentrated wound inner layer coil is inserted between teeth, and the same number of outer slots as the inner slot through which the distributed outer layer coil is inserted between the branch tooth portions forming a pair of the teeth; The total number of the inner slots and the outer slots is the same as the number of segments, and the power supply brush of the anode and the power supply brush of the cathode are from a normal position on the magnetic pole center line passing through the center in the circumferential direction of the magnetic pole. Arranged by shifting in opposite directions along the circumferential direction, rectification by the power supply brush of the anode and rectification by the power supply brush of the cathode are alternately performed. It has as its gist.

  According to this configuration, even when the total number of inner slots and outer slots is divisible by the number of magnetic poles, rectification by the anode power supply brush and rectification by the anode power supply brush are alternately performed. Therefore, the amount of change in the current value during driving of the DC motor can be reduced and magnetic noise can be reduced as compared with a DC motor configured to simultaneously perform rectification using different-polarity power supply brushes.

  According to a fourth aspect of the present invention, in the DC motor according to the third aspect, the power feeding is adjacent to the sliding contact portion that is in sliding contact with the segment in each of the power supply brushes, and is adjacent to the normal position of the adjacent power supply brush. The gist of the invention is that a high-resistance brush is provided that is shifted in the direction opposite to the direction in which the brush is shifted.

  According to this configuration, it is possible to suppress the occurrence of sparks when the power supply brushes come into contact with the segments and when they are separated from each other.

  According to the present invention, it is possible to provide a direct current motor capable of suppressing the increase in size due to the armature coil and suppressing the vibration without reducing the output.

Sectional drawing of the DC motor of 1st Embodiment. The schematic diagram which expand | deployed the DC motor of 1st Embodiment planarly. The schematic diagram which shows the coil end part in the direct-current motor of 1st Embodiment. The schematic diagram which shows the coil end part in the direct current motor provided with the armature coil of the conventional distributed winding. Sectional drawing of the DC motor provided with the armature coil of the conventional distributed winding. The schematic diagram which expand | deployed the DC motor provided with the armature coil of the conventional distributed winding to planar shape. Sectional drawing of the DC motor of 2nd Embodiment. The schematic diagram which expand | deployed the DC motor of 2nd Embodiment planarly. Sectional drawing of the DC motor of 3rd Embodiment. The schematic diagram which expand | deployed the DC motor of 3rd Embodiment in planar shape. Sectional drawing of the DC motor provided with the inner layer coil and outer layer coil of concentrated winding. The schematic diagram which expand | deployed the DC motor provided with the inner layer coil and outer layer coil of concentrated winding to planar shape. Schematic of the DC motor of the fourth embodiment. The schematic diagram which expand | deployed the direct-current motor of 4th Embodiment in planar shape. The schematic diagram which expand | deployed the DC motor of 5th Embodiment planarly. Schematic of the DC motor of the fifth embodiment. Schematic of the DC motor of the fifth embodiment. Schematic of a conventional DC motor. The schematic diagram which expand | deployed the conventional DC motor planarly. Schematic of a conventional DC motor. Explanatory drawing for demonstrating the relationship between the total number of slots, the number of magnetic poles, and a problem. (A) is a graph showing the relationship between time and induced voltage in the DC motor of the fifth embodiment, and (b) shows the relationship between time in the DC motor of the fifth embodiment and the current supplied to the armature coil. Graph. (A) is a graph which shows the relationship between time and the induced voltage in the conventional DC motor, (b) is a graph which shows the relationship between the time in the conventional DC motor and the current supplied to the armature coil. Schematic of the DC motor of another form. The schematic diagram which expand | deployed the DC motor of another form in planar shape. Schematic of the DC motor of another form. The schematic diagram which expand | deployed the DC motor of another form in planar shape. Explanatory drawing for demonstrating the aspect of the inner layer coil of the DC motor of another form. Explanatory drawing for demonstrating the aspect of the outer layer coil of the DC motor of another form. The schematic diagram which expand | deployed the DC motor of another form in planar shape. Explanatory drawing for demonstrating the aspect of the inner layer coil of the DC motor of another form. The schematic diagram which expand | deployed the DC motor of another form in planar shape. The schematic diagram which expand | deployed the DC motor of another form in planar shape. Sectional drawing of the DC motor of another form. Sectional drawing of the DC motor of another form.

(First embodiment)
A first embodiment of the present invention will be described below with reference to the drawings.
FIG. 1 shows a cross-sectional view of a DC motor M1 of the first embodiment. As shown in FIG. 1, the DC motor M <b> 1 includes a stator 1 and an armature 2 disposed inside the stator 1. Four magnets 4 a to 4 d as magnetic poles are fixed to the inner peripheral surface of a substantially cylindrical yoke housing 3 constituting the stator 1. The magnets 4a to 4d are arranged so that they are equiangularly spaced in the circumferential direction (90 ° intervals in the present embodiment), and N poles and S poles are alternately arranged in the circumferential direction. The direct current motor M1 has four magnets 4a to 4d, so that the number P of magnetic poles is “4”.

  As shown in FIGS. 1 and 2, the armature 2 includes a rotating shaft 11, an armature core 12 fixed to the rotating shaft 11, and a substantially cylindrical commutator 13 that is also fixed to the rotating shaft 11. And. The armature 2 is supported so as to be rotatable with respect to the stator 1 by the rotation shaft 11 being pivotally supported by the stator 1. Then, the armature core 12 and the commutator 13 are both fixed to the rotating shaft 11 and thereby integrally rotated with the rotation of the rotating shaft 11. In a state where the armature 2 is disposed inside the stator 1, the armature core 12 is opposed to the magnets 4 a to 4 d in the radial direction, and the anode brush 14 and the cathode side disposed on the outer periphery of the commutator 13. The brush 15 is pressed against the commutator 13 so as to be slidable. The anode-side brush 14 and the cathode-side brush 15 are arranged at the same 90 ° interval as the interval between the magnets 4a to 4d adjacent in the circumferential direction. The anode-side brush 14 is disposed at a position corresponding to the circumferential center of the N-pole magnet 4a, and the cathode-side brush 15 is disposed at a position corresponding to the circumferential center of the S-pole magnet 4b. Yes. The armature 2 is supplied with current through the anode side brush 14 and the cathode side brush 15.

  As shown in FIG. 2, the commutator 13 includes ten segments 16 arranged in parallel on the outer peripheral surface of a cylindrical holding member (not shown) made of an insulating resin material. FIG. 2 is a schematic diagram in which the DC motor M1 is developed in a planar shape. The ten segments 16 are arranged so as to form a substantially cylindrical shape on the outer periphery of the holding member, and the anode side brush 14 and the cathode side brush 15 are pressed and contacted from outside in the radial direction. In this embodiment, as shown in FIG. 2, segment numbers “1” to “10” are attached to ten segments 16 arranged in parallel in the circumferential direction.

  In the commutator 13, the segments 16 arranged at the same angular intervals as the magnets having the same poles are short-circuited (electrically connected) by a short-circuit member 17 fixed to one end of the segment 16 in the axial direction. ) Specifically, in the stator 1, two N-pole magnets 4 a and 4 c (or two S-pole magnets 4 b and 4 d) are arranged at an interval of 180 °. Therefore, the two segments 16 (for example, the segment 16 with the segment number “1” and the segment 16 with the segment number “6”) arranged at an interval of 180 ° are short-circuited to each other by the short-circuit member 17 to have the same potential. . In FIG. 2, two virtual brushes are schematically shown in order to schematically show how the anode 16 and the cathode 15 are arranged by short-circuiting the segment 16 by the short-circuit member 17. It is shown by a chain line. In addition, the short circuit member 17 is comprised so that predetermined segments 16 can be short-circuited, for example using a conducting wire. The short-circuit member 17 may be formed by punching a conductive plate material such as a copper plate into a predetermined shape.

  As shown in FIG. 1, the armature core 12 is integrally formed with a cylindrical core back 20 and five teeth 21 to 25 extending radially outward from the outer peripheral surface of the core back 20. In addition, the core back 20 is fixed to the rotary shaft 11 by being externally fitted to the rotary shaft 11. Here, as shown in FIG. 2, the number S of segments 16 provided in the commutator 13 is set based on the number N of teeth 21 to 25 provided in the armature core 12. , S = 2N is set. Therefore, the number S of segments 16 provided in the commutator 13 of this embodiment is set to “10”.

  As shown in FIG. 1, the five teeth 21 to 25 are integrally formed at positions that are equiangularly spaced in the circumferential direction with respect to the core back 20 (72 ° intervals in the present embodiment). And the tip part of each tooth 21-25 is provided with a pair of branch teeth parts 26a, 26b that are bifurcated so as to be separated in the circumferential direction, and each tooth 21-25 is provided at the tip part. By forming the branching tooth portions 26a and 26b, the shape viewed from the axial direction is substantially Y-shaped. The pair of branch teeth portions 26a and 26b provided in each of the teeth 21 to 25 are formed so as to be away from each other in the circumferential direction toward the tip, and the adjacent two teeth (the circumferences of the teeth 21 to 25). Of two teeth adjacent to each other in the direction) and the distance between the branch teeth 26a of the other tooth adjacent to the branch teeth 26a is a pair of branch teeth 26a and 26b. It is narrower than the interval between them. Further, in each of the teeth 21 to 25, a portion on the proximal end side that is radially inward of the branch tooth portions 26 a and 26 b is an inner winding portion 27. Further, in each of the teeth 21 to 25, a plate-like extending portion 28 extending along the circumferential direction is integrally formed at the distal ends of the branching tooth portions 26a and 26b that make a pair. Two extending portions 28 formed in the paired branch teeth portions 26a and 26b are extended in a direction approaching each other from the tip portions of the branch teeth portions 26a and 26b. A total of ten extending portions 28 provided in the armature core 12 are provided at equal angular intervals in the circumferential direction, and are formed to have a substantially cylindrical shape as a whole.

  The armature core 12 has an inner slot 31 between the teeth 21 to 25 adjacent in the circumferential direction, and an outer slot 32 between the branching tooth portions 26a and 26b forming a pair. Each inner slot 31 is mainly constituted by a space between the inner winding portions 27 adjacent in the circumferential direction, and each outer slot 32 is constituted by a space between the paired branch tooth portions 26a and 26b. Since the armature core 12 of this embodiment includes five teeth 21 to 25, the armature core 12 includes five inner slots 31 and five outer slots 32. The inner slot 31 and the outer slot 32 are formed at positions shifted in the circumferential direction, and each outer slot 32 is located between the inner slots 31 adjacent in the circumferential direction. In the present embodiment, as shown in FIG. 2, the teeth numbers “1” to “10” are sequentially given in the circumferential direction to the branch tooth portions 26 a and 26 b of the five teeth 21 to 25. The tooth number is a number shown at the tip of the branching tooth portions 26a and 26b in FIG.

  As shown in FIG. 1, a plurality of armature coils are wound around the armature core 12 configured as described above by winding a conducting wire 41. The plurality of armature coils are wound around the five inner layer coils 42a to 42e wound around the inner winding portion 27 which is a portion on the base end side of each of the teeth 21 to 25, and the branch tooth portions 26a and 26b. These are five rotated outer layer coils 43a to 43e.

  Here, the order of winding the inner layer coils 42a to 42e and the outer layer coils 43a to 43e around the armature core 12 will be described in detail with reference to FIG. In FIG. 2, the inner layer coils 42 a to 42 e are illustrated by middle lines, and the outer layer coils 43 a to 43 e are illustrated by thick lines. The conducting wire 41 is first connected to the riser of the segment 16 with the segment number “1”, and is wound a plurality of times by concentrated winding from the segment 16 with the segment number “1” to the inner winding portion 27 of the tooth 21. The inner layer coil 42a is formed. Next, the conductive wire 41 is hooked to the riser of the segment 16 with the segment number “2”, and the two branch teeth portions 26a and 26b (26b) adjacent to each other in the center among the total four branch teeth portions 26a and 26b of the teeth 21 and 22 ( That is, the outer layer coil 43a is formed by winding the branch tooth portion 26b with the tooth number “2” and the branch tooth portion 26a with the tooth number “3” a plurality of times by distributed winding. In the present specification, “distributed winding” means winding a conducting wire across a plurality of teeth. At this time, the inner layer coil 42a wound earlier and the outer layer coil 43a wound later are formed at positions shifted from each other in the radial direction so as not to overlap in the axial direction (see FIG. 1). ). Further, the circumferential center of the inner layer coil 42 a and the circumferential center of the outer layer coil 43 a are shifted from each other in the circumferential direction of the armature core 12.

  Thereafter, similarly, the conductive wire 41 is alternately wound around the inner winding portion 27 and the branching tooth portions 26a and 26b, thereby forming the inner layer coils 42b to 42e and the outer layer coils 43b to 43e alternately. Go. Then, each time the inner layer coils 42b to 42e and the outer layer coils 43b to 43e are formed, the conducting wire 41 is hooked to the segments 16 arranged in parallel in the circumferential direction.

  That is, the conductive wire 41 is hooked to the riser of the segment 16 with the segment number “3”, and then wound around the inner winding portion 27 of the tooth 22 a plurality of times by concentrated winding to form the inner layer coil 42b. Hooked to riser of segment 16 with segment number “4”. Next, the conductive wire 41 has the branch teeth portions 26a and 26b adjacent to each other at the center among the total four branch teeth portions 26a and 26b of the teeth 22 and 23 (that is, the branch tooth portion 26b having the tooth number “4” and the tooth number “5”). After the outer layer coil 43b is formed by being wound around the branch tooth portion 26a) by a plurality of distributed windings, it is hooked to the riser of the segment 16 with the segment number “5”. Next, the conductive wire 41 is wound around the inner winding portion 27 of the tooth 23 a plurality of times by concentrated winding to form the inner layer coil 42c, and then hooked to the segment 16 of the segment number “6”. Out of a total of 24 branch tooth portions 26a and 26b, the branch tooth portions 26a and 26b adjacent to each other in the center (that is, the branch tooth portion 26b having the tooth number “6” and the branch tooth portion 26a having the tooth number “7”) are distributed. The outer layer coil 43c is formed by being wound a plurality of times. Next, the conductive wire 41 is hooked to the segment 16 having the segment number “7”, and then is wound around the inner winding portion 27 of the tooth 24 a plurality of times by concentrated winding, thereby forming the inner layer coil 42d. After being hooked to the segment 16 of “8”, among the total four branch teeth portions 26a and 26b of the teeth 24 and 25, the branch teeth portions 26a and 26b adjacent to each other in the center (that is, the branch teeth portion of the tooth number “8”) The outer layer coil 43d is formed by being distributed a plurality of times by distributed winding around the branch tooth portion 26b) of 26a and the tooth number “9”. Next, the conductive wire 41 is hooked to the segment 16 with the segment number “9”, and then is wound around the inner winding portion 27 of the tooth 25 a plurality of times by concentrated winding to form an inner layer coil 42e. After being hooked to the segment 16 of “10”, among the total four branch teeth portions 26a and 26b of the teeth 25 and 21, the branch teeth portions 26a and 26b adjacent to each other in the center (that is, the branch teeth portion having the tooth number “10”) 26b and a branch tooth portion 26a) having a tooth number “1” are wound by distributed winding a plurality of times to form an outer layer coil 43e, and the conducting wire 41 is hooked to the segment 16 having a segment number “1”. Thus, the winding of all the inner layer coils 42a to 42e and the outer layer coils 43a to 43e is completed.

  In this way, all the inner layer coils 42a to 42e and the outer layer coils 43a to 43e are formed continuously from the beginning to the end with one conductive wire 41, and the inner layer coils 42a to 42e and the outer layer coils 43a to 43e. Winding around the armature core 12 is automatically performed using a single flyer (not shown). And the conducting wire 41 hooked to the riser of each segment 16 is fused (connected) and electrically connected to each segment 16, whereby the winding of each inner layer coil 42 a to 42 e and each outer layer coil 43 a to 43 e is wound. The beginning and end of winding are each electrically connected to the hooked segment 16. In the present embodiment, each segment 16 is connected to one end of any one of the inner layer coils 42a to 42e and one end of any one of the outer layer coils 43a to 43e.

  Here, FIG. 5 shows a sectional view of a conventional DC motor M10 in which an armature coil is wound by distributed winding, and FIG. 6 shows a schematic diagram of the DC motor M10 developed in a planar shape. As shown in FIGS. 5 and 6, the DC motor M <b> 10 includes a stator 53 in which four magnets 52 are fixed to the inner peripheral surface of a substantially cylindrical yoke housing 51, and a stator 53 formed on the inner side of the stator 53. And an armature 54 disposed so as to be rotatable with respect to the stator 53. The armature core 56 fixed to the rotary shaft 55 of the armature 54 extends radially from the outer peripheral surface of the core back 56a to the outer side in the radial direction. Ten teeth 56b are integrally formed. The armature core 56 has a total of ten slots 56c between teeth 56b adjacent in the circumferential direction. Ten armature coils 57 are wound around the armature core 56 by distributed winding, and each armature coil 57 is wound around two teeth 56b so as to straddle one slot 56c. ing. Further, a commutator 59 having ten segments 58 arranged in parallel in the circumferential direction is fixed to the rotating shaft 55, and one end portion of two armature coils 57 is provided in each segment 58. It is connected. Furthermore, the commutator 59 is in pressure contact with an anode brush 61 and a cathode brush 62 for supplying current to the armature coil 57. In the DC motor M10 having such distributed winding armature coils 57, the coil end portions 57a of the armature coils 57 overlap in the axial direction as shown in FIG. It gets bigger. The coil end portion 57 a is a portion of the armature coil 57 that protrudes in the axial direction from the end surface of the armature core 56 in the axial direction.

  On the other hand, as shown in FIGS. 1 and 3, in the DC motor M <b> 1 of the present embodiment, the inner layer coils 42 a to 42 e are wound around the inner winding portions 27 of the teeth 21 to 25 by concentrated winding. Therefore, the inner layer coils 42 a to 42 e do not overlap each other in the radial direction, and the inner layer coils 42 a to 42 e do not overlap in the axial direction on both sides in the axial direction of the armature core 12. The outer layer coils 43a to 43e are wound around the two branch teeth portions 26a and 26b adjacent in the circumferential direction, but the outer layer coils 43a to 43e are wound around the different branch tooth portions 26a and 26b. Therefore, the outer layer coils 43a to 43e do not overlap each other in the radial direction, and the outer layer coils 43a to 43e adjacent in the circumferential direction overlap in the axial direction on both sides in the axial direction of the armature core 12. Absent. Further, since the outer layer coils 43a to 43e are wound around the teeth 21 to 25 on the radially outer side than the inner layer coils 42a to 42e, the outer layer coils 43a to 43e and the inner layer coils 42a to 42e are displaced in the radial direction. The both sides of the child core 12 in the axial direction do not overlap each other in the axial direction. Therefore, the coil end portions 45 of the inner layer coils 42a to 42e (the portions protruding in the axial direction from the end surfaces of the armature core 12 in the axial direction in the inner layer coils 42a to 42e) and the coil ends of the outer layer coils 43a to 43e. Since the portion 46 (the portion protruding in the axial direction from the end surface in the axial direction of the armature core 12 in each of the outer layer coils 43a to 43e) does not overlap in the axial direction, the armature coil 57 of the distributed winding of the conventional DC motor M10. The coil end portions 45 and 46 can be made smaller in the axial direction than (see FIG. 4).

As described above, according to the first embodiment, the following operational effects are obtained.
(1) Since the outer layer coils 43a to 43e are wound around the teeth 21 to 25 on the outer peripheral side of the inner layer coils 42a to 42e, they do not overlap with the inner layer coils 42a to 42e in the axial direction. Therefore, the coil end portions 45 and 46 of the inner layer coils 42a to 42e and the outer layer coils 43a to 43e can be prevented from becoming larger in the axial direction, and consequently the axial size of the DC motor M1 can be suppressed. And since it is not necessary to reduce the number of turns of the inner layer coils 42a to 42e and the outer layer coils 43a to 43e in order to suppress the axial height of the coil end part, the output is reduced without lowering the space factor. The increase in the size of the DC motor M1 in the axial direction can be suppressed without making it. In addition, in the case of a size equivalent to that of a conventional DC motor including a distributed winding armature coil, the space factor can be increased by increasing the number of turns of the inner layer coils 42a to 42e and the outer layer coils 43a to 43e. The output of the DC motor M1 can be increased. Further, since the circumferential center of each inner layer coil 42a to 42e and the circumferential center of each outer layer coil 43a to 43e are shifted in the circumferential direction, the magnetic flux is larger than that of a DC motor having concentrated winding armature coils. Can be moderated. Therefore, it is possible to suppress vibrations that occur when the DC motor M1 is driven.

  (2) Since each of the teeth 21 to 25 has a pair of branching teeth portions 26a and 26b that are bifurcated at a distal end portion so as to be separated from each other in the circumferential direction, The inner layer coils 42a to 42e are wound, and the outer layer coils 43a to 43e are wound around the two branch tooth portions 26a and 26b adjacent in the circumferential direction so as to straddle the teeth 21 to 25 adjacent in the circumferential direction. The outer layer coils 43a to 43e can be easily formed on the outer peripheral sides of 42a to 42e. Furthermore, the circumferential center of each inner layer coil 42a-42e and the circumferential center of each outer layer coil 43a-43e can be easily shifted in the circumferential direction. Moreover, since the inner layer coils 42a-42e are wound by the concentrated winding in the base end part of the teeth 21-25, ie, the part (inner winding part 27) which is not branched, the base end of the teeth 21-25 The vicinity of the part can be set to a high space factor. Further, each of the teeth 21 to 25 is formed in a substantially Y shape having a pair of branch teeth portions 26a and 26b, so that, for example, an armature core having ten teeth without the branch teeth portions 26a and 26b. Compared with the case where the inner layer coils 42a to 42e and the outer layer coils 43a to 43e are wound, the slot area can be increased, and a higher space factor can be achieved.

  (3) The commutator 13 includes as many segments 16 as the teeth 21 to 25, and each segment 16 has one end of the inner layer coils 42a to 42e and one end of the outer layer coils 43a to 43e. Since the inner layer coils 42a to 42e and the outer layer coils 43a to 43e are alternately wound, all the inner layer coils 42a to 42e and the outer layer coils 43a to 43e are continuously connected by one conductor 41. Can be formed. Therefore, the inner layer coils 42a to 42e and the outer layer coils 43a to 43e can be easily wound around the armature core 12.

  (4) In a conventional DC motor in which all armature coils are wound in distributed winding, the armature coils are enlarged in the axial direction by overlapping the coil end portions on the axial end surfaces of the armature cores. Sometimes. Then, since the length of the conducting wire which comprises an armature coil becomes long, there exists a possibility that winding resistance may become large. However, in the DC motor M1 of the present embodiment, the coil end portion 45 of the inner layer coils 42a to 42e and the coil end portion 46 of the outer layer coils 43a to 43e do not overlap in the axial direction, so that the winding resistance increases. Can be suppressed.

  (5) Since the coil end portions 45 of the inner layer coils 42a to 42e and the coil end portions 46 of the outer layer coils 43a to 43e do not overlap in the axial direction, all the armature coils are wound with distributed winding. Compared to the motor, the balance of the armature 2 is improved. Therefore, it is possible to further suppress the vibration of the armature 2 when the DC motor M1 is driven.

  (6) A plate-like extending portion 28 extending in the circumferential direction is integrally formed at the distal end portion of each branch tooth portion 26a, 26b. Therefore, the extended portion 28 prevents the outer layer coils 43a to 43e from protruding outward in the radial direction.

(Second Embodiment)
Hereinafter, a second embodiment of the present invention will be described with reference to the drawings. In the second embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  FIG. 7 is a cross-sectional view of the DC motor M2 of the second embodiment, and FIG. 8 is a schematic diagram of the DC motor M2 developed in a planar shape. The DC motor M2 of the second embodiment is different from the DC motor M1 of the first embodiment in the armature configuration. As shown in FIGS. 7 and 8, the armature 81 arranged inside the stator 1 is fixed to the rotary shaft 11, the armature core 82 fixed to the rotary shaft 11, and the rotary shaft 11. And a substantially cylindrical commutator 83. The armature 81 is instructed to be rotatable with respect to the stator 1 when the rotary shaft 11 is pivotally supported by the stator 1. In the state where the armature 81 is disposed inside the stator 1, the armature core 82 is opposed to the magnets 4 a to 4 d in the radial direction, and the anode-side brush 14 disposed on the outer periphery of the commutator 83 and The cathode brush 15 is pressed against the commutator 83 so as to be slidable.

  As shown in FIG. 8, the commutator 83 includes twelve segments 16 arranged in parallel on the outer peripheral surface of a cylindrical holding member (not shown) made of an insulating resin material. In this embodiment, as shown in FIG. 8, segment numbers “1” to “12” are attached to 12 segments 16 arranged in the circumferential direction. In the commutator 83, the segments 16 arranged at the same angular intervals as the magnetic poles having the same poles are short-circuited by a short-circuit member 85 fixed to one end of the segment 16 in the axial direction. That is, in the stator 1, the two N-pole magnets 4a and 4c are arranged at an interval of 180 °, and therefore, two segments 16 (for example, the segment of the segment number “1”) arranged at an interval of 180 ° are disposed. 16 and the segment 16) having the segment number “7” are short-circuited to each other by the short-circuit member 85 to have the same potential. FIG. 8 shows two virtual brushes in order to schematically show a state in which the anode 16 and the cathode 15 are arranged by short-circuiting the segment 16 by the short-circuit member 85. It is shown by a chain line.

  As shown in FIG. 7, the armature core 82 is formed integrally with a cylindrical core back 20 and six teeth 91 to 96 extending radially outward from the outer peripheral surface of the core back 20. It becomes. Here, the number S of segments 16 provided in the commutator 83 is set based on the number N of teeth 91 to 96 provided in the armature core 82 as in the first embodiment, and S = 2N. It is set to satisfy. Therefore, the number S of segments 16 provided in the commutator 83 of the present embodiment is set to “12”.

  The five teeth 91 to 96 are integrally formed at positions that are equiangularly spaced in the circumferential direction with respect to the core back 20 (60 ° intervals in the present embodiment). It has the same shape as each of the teeth 21 to 25 of the embodiment. That is, a pair of branch teeth portions 26a and 26b similar to those of the first embodiment are provided at the tip portions of the teeth 91 to 96, and the teeth 91 to 96 are more radial than the branch teeth portions 26a and 26b. A portion on the proximal end side that is the inner side is an inner winding portion 27. Further, in each of the teeth 91 to 96, an extending portion 28 is integrally formed at the distal end portion of the branching tooth portions 26a and 26b that make a pair. The armature core 82 has the inner slot 31 between the teeth 91 to 96 adjacent in the circumferential direction, and the outer slot 32 between the branching tooth portions 26a and 26b forming a pair. Since the armature core 82 of the present embodiment includes six teeth 91 to 96, the armature core 82 includes five inner slots 31 and six outer slots 32. Further, in the armature core 82, the inner slot 31 and the outer slot 32 are formed at positions shifted in the circumferential direction, and each outer slot 32 is located between the inner slots 31 adjacent in the circumferential direction. In the present embodiment, as shown in FIG. 8, the teeth numbers “1” to “12” are sequentially given to the branch teeth portions 26 a and 26 b of the six teeth 91 to 96 in the circumferential direction. The tooth number is a number shown at the tip of the branching tooth portions 26a and 26b in FIG.

  As shown in FIG. 7, a plurality of armature coils are wound around the armature core 82 configured as described above by winding a conducting wire 41. The plurality of armature coils are wound around six inner layer coils 102a to 102f wound around the inner winding portion 27, which is a portion on the base end side of each of the teeth 91 to 96, and the branching tooth portions 26a and 26b. Six outer layer coils 103a to 103f that have been rotated.

  Here, the order of winding the inner layer coils 102a to 102f and the outer layer coils 103a to 103f around the armature core 82 will be described in detail with reference to FIG. In FIG. 8, the inner layer coils 102 a to 102 f are illustrated by middle lines, and the outer layer coils 103 a to 103 f are illustrated by thick lines.

  In this embodiment, two flyers arranged at intervals of 180 ° are simultaneously operated, and all the inner layer coils 102a to 102f and the outer layer coils 103a to 103f are wound by the two conductive wires 41. In one flyer, the conducting wire 41 is first connected to the riser of the segment 16 with the segment number “1”, and then wound around the inner winding portion 27 of the tooth 91 a plurality of times by concentrated winding to connect the inner layer coil 102a. Form. Then, the conductive wire 41 is hooked to the riser of the segment 16 with the segment number “2”, and then multiple times by concentrated winding on the inner winding portion 27 of the tooth 96 adjacent to the tooth 91 around which the inner layer coil 102a is wound. The inner layer coil 102f is formed by being wound. Next, after the conducting wire 41 is hooked to the riser of the segment 16 with the segment number “9”, it is concentrated multiple times on the inner winding portion 27 of the tooth 95 adjacent to the tooth 96 around which the inner layer coil 102f is wound. The inner layer coil 102e is wound to be hooked to the segment 16 having the segment number “10”. Next, a plurality of the conductive wires 41 are distributed on the adjacent branch tooth portions 26a and 26b of the teeth 95 and 96 (that is, the branch tooth portion 26b having the tooth number “10” and the branch tooth portion 26a having the tooth number “11”) by distributed winding. The outer layer coil 103e is formed by being wound. At this time, the outer layer coil 103e is formed at a position radially displaced from the previously wound inner layer coils 102a, 102e, and 102f, and does not overlap in the axial direction. Next, after the conducting wire 41 is hooked to the riser of the segment 16 with the segment number “11”, it is adjacent to the outer layer coil 103e formed immediately before in the circumferential direction, that is, the branch tooth portions 26a adjacent to each other of the teeth 94 and 95. , 26b (that is, the branch tooth portion 26b with the tooth number “8” and the branch tooth portion 26a with the tooth number “9”) are wound a plurality of times by distributed winding to form the outer layer coil 103d. Next, after the conducting wire 41 is hooked to the riser of the segment 16 with the segment number “6”, it is adjacent to the outer layer coil 103 d formed immediately before in the circumferential direction, that is, the branch tooth portions 26 a adjacent to each other of the teeth 93 and 94. , 26b (that is, the branch tooth portion 26b with the tooth number “6” and the branch tooth portion 26a with the tooth number “7”) are wound a plurality of times by distributed winding to form the outer layer coil 103c. Then, the conducting wire 41 is hooked to the segment 16 with the segment number “7”, and the winding of the armature coil in one flyer is completed.

  As described above, in one flyer, the inner layer coils 102a, 102f, and 102e are continuously wound around the inner winding portions 27 of the three teeth 91, 96, and 95 that are continuously arranged in the circumferential direction. 102a, 102f, 102e are circumferentially arranged continuously with respect to the six branch teeth portions 26a, 26b of the four teeth 96, 95, 94, 93 continuously arranged in the circumferential direction including the three teeth wound around Three outer layer coils 103e, 103d, and 103c are wound in order. At this time, the flyer hooks the conductive wire 41 to the segment 16 each time the inner layer coils 102a, 102f, 102e and the outer layer coils 103e, 103d, 103c are formed. Similarly, the other flyer is connected to the inner winding portion 27 of the three teeth 94, 93, 92 continuously connected in the circumferential direction after connecting the lead wire 41 to the riser of the segment 16 with the segment number “7”. Inner layer coils 102d, 102c, 102b are wound, and then the four teeth 93, 92, 91, 96 continuously arranged in the circumferential direction including the three teeth around which the inner layer coils 102d, 102c, 102b are wound. Three outer layer coils 103b, 103a, and 103f are wound around the six branch teeth portions 26a and 26b sequentially in the circumferential direction. In the other flyer as well, each time the inner layer coils 102d, 102c, 102b and the outer layer coils 103b, 103a are formed, the conductor 41 is connected to the segment numbers “8”, “3”, “4”, “5”. , “12” are sequentially hooked to the risers of the segment 16. And the other flyer will complete | finish winding of an armature coil, if the conducting wire 41 is connected to the segment 16 of segment number "1".

  And the conducting wire 41 hooked to the riser of each segment 16 is fused (connected) and electrically connected to each segment 16, whereby the winding of each inner layer coil 102 a to 102 f and each outer layer coil 103 a to 103 f is performed. The beginning and end of winding ends are each electrically connected to the hooked segment 16. In the present embodiment, each segment 16 is connected to any two of the end portions of the inner layer coils 102a to 102f and the outer layer coils 103a to 103f. More specifically, the four segments 16 having segment numbers “1”, “4”, “7”, and “10” have inner layer coils wound around the teeth adjacent to each other in the circumferential direction among the teeth 91 to 96, and One end of each outer layer coil is connected to each other. Of the eight segments 16 obtained by excluding the segments 16 having the segment numbers “1”, “4”, “7”, and “10” from the 12 segments 16, half of the four segments 16 (this embodiment) In the segment numbers “2”, “3”, “8”, and “9”, the segments 16) are connected to two ends of two inner layer coils adjacent to each other in the circumferential direction among the inner layer coils 102a to 102f. ing. Then, the other half of the four segments 16 (segment numbers “5”, “6”, “11”, “12” in this embodiment) are adjacent in the circumferential direction among the outer layer coils 103a to 103f. Two ends of two matching outer layer coils are connected to each other.

  As shown in FIG. 7, in the DC motor M2 of the present embodiment, the inner layer coils 102a to 102f are wound by concentrated winding around the inner winding portions 27 of the teeth 91 to 96, as in the first embodiment. Therefore, the inner layer coils 102 a to 102 f do not overlap in the axial direction on both sides of the armature core 82 in the axial direction. Further, the outer layer coils 103a to 103f are wound around two branch tooth portions 26a and 26b adjacent in the circumferential direction, respectively, but the outer layer coils 103a to 103f are wound around different branch tooth portions 26a and 26b, respectively. Therefore, the outer layer coils 103 a to 103 f adjacent in the circumferential direction do not overlap in the axial direction on both sides in the axial direction of the armature core 82. Furthermore, since the outer layer coils 103a to 103f are wound around the teeth 91 to 96 on the radially outer side than the inner layer coils 102a to 102f, the outer layer coils 103a to 103f and the inner layer coils 102a to 102f are displaced in the radial direction. The both sides of the child core 82 in the axial direction do not overlap each other in the axial direction. For these reasons, the coil end portions 104 of the inner layer coils 102a to 102f (the portions protruding in the axial direction from the end surfaces in the axial direction of the armature core 82 in the inner layer coils 102a to 102f) and the coil ends of the outer layer coils 103a to 103f. Since the portion 105 (the portion protruding in the axial direction from the axial end face of the armature core 82 in each of the outer layer coils 103a to 103f) does not overlap in the axial direction, the coil end portions 104 and 105 should be made smaller in the axial direction. Can do.

As described above, according to the second embodiment, in addition to the same effects as (1), (2), (4) to (6) of the first embodiment, the following functions and effects are provided. .
(1) The commutator 83 includes only 12 segments 16, which are twice as many as the teeth 91 to 96. The four segments 16 out of the 12 segments are connected to the ends of the inner layer coil and the outer layer coil wound around the teeth adjacent to each other in the circumferential direction among the teeth 91 to 96, respectively. . Further, the other four segments 16 out of the remaining eight segments 16 are connected to the ends of two inner layer coils adjacent to each other in the circumferential direction among the inner layer coils 102a to 102f, and the other half. Two end portions of two outer layer coils adjacent in the circumferential direction among the outer layer coils 103a to 103f are connected to the four segments 16 two by two. Therefore, by using two flyers simultaneously and winding the inner layer coils 102a to 102f and then winding the outer layer coils 103a to 103f, the inner layer coils 102a to 102f are continuously connected by one conductor 41 in each flyer. And the outer layer coils 103a to 103f can be wound. Thus, by using two flyers simultaneously, the time required for winding the inner layer coils 102a to 102f and the outer layer coils 103a to 103f can be shortened, and the productivity of the DC motor M2 can be improved. .

(Third embodiment)
Hereinafter, a third embodiment of the present invention will be described with reference to the drawings. In the third embodiment, the same components as those in the first and second embodiments are denoted by the same reference numerals, and the description thereof is omitted.

  FIG. 9 is a cross-sectional view of the DC motor M3 according to the third embodiment, and FIG. 10 is a schematic diagram in which the DC motor M3 is developed in a planar shape. The DC motor M3 of the third embodiment is different from the DC motor M1 of the first embodiment and the DC motor M2 of the second embodiment in the number of magnets (magnetic poles) provided in the stator and the configuration of the armature. Is different.

  As shown in FIG. 9, the stator 131 has six magnets 132 a to 132 f as magnetic poles fixed to the inner peripheral surface of the yoke housing 3. The six magnets 132a to 132f are arranged so as to be equiangularly spaced in the circumferential direction (60 ° interval in the present embodiment), and N poles and S poles are alternately arranged in the circumferential direction. The DC motor M3 has six magnets 132a to 132f, so that the number P of magnetic poles is “6”.

  As shown in FIGS. 9 and 10, the armature 141 arranged inside the stator 131 is fixed to the rotary shaft 11, the armature core 142 fixed to the rotary shaft 11, and the rotary shaft 11. And a substantially cylindrical commutator 143. The armature 141 is instructed to be rotatable with respect to the stator 131 when the rotating shaft 11 is pivotally supported by the stator 1. In the state where the armature 141 is disposed inside the stator 131, the armature core 142 is opposed to the magnets 132 a to 132 f in the radial direction, and the anode-side brush 14 disposed on the outer periphery of the commutator 143 and The cathode brush 15 is pressed against the commutator 143 so as to be slidable. The anode-side brush 14 and the cathode-side brush 15 are arranged with an interval that is an odd multiple of the interval between the magnets 132a to 132f adjacent in the circumferential direction, and in this embodiment, 180 °, which is three times 60 °. Are arranged with an interval of. The anode-side brush 14 is disposed at a position corresponding to the center in the circumferential direction of the lower N-pole magnet 132d in FIG. 9, and the cathode-side brush 15 is disposed on the upper S-pole magnet 132a in FIG. It is arranged at a position corresponding to the circumferential center.

  As shown in FIG. 10, the commutator 143 includes 24 segments 16 arranged in parallel on the outer peripheral surface of a cylindrical holding member (not shown) made of an insulating resin material. In the present embodiment, as shown in FIG. 10, segment numbers “1” to “24” are assigned to 24 segments 16 arranged in the circumferential direction. In the commutator 143, the segments 16 arranged at the same angular intervals as the magnetic poles having the same poles are short-circuited by a short-circuit member 145 fixed to one end of the segment 16 in the axial direction. That is, in the stator 1, the N-pole magnets 132b, 132d, and 132f are arranged at intervals of 120 °. 16 and the segment 16 with the segment number “9” and the segment 16 with the segment number “17” are short-circuited to each other by the short-circuit member 145 to have the same potential. And in FIG. 10, in order to show typically a mode that the state where the anode side brush 14 and the cathode side brush 15 are arrange | positioned by short-circuiting the segment 16 by the short circuit member 145, a virtual brush is shown with a dashed-dotted line. It is shown in

  As shown in FIG. 9, the armature core 142 is formed integrally with a cylindrical core back 20 and eight teeth 151 to 158 extending from the outer peripheral surface of the core back 20 toward the radially outer side. It becomes. Here, in the present embodiment, the number N of teeth 151 to 158 provided in the armature core 142 satisfies N = P ± 2 (provided that N = 6 when P = 4) based on the number P of magnetic poles. Based on the fact that the number P of magnetic poles is “6”, the number N of the teeth 151 to 158 is set to “8”. The number S of segments 16 provided in the commutator 143 is set based on the number P of magnetic poles and the number N of teeth 151 to 158 so as to satisfy “S = N × (P / 2)”. Is set to Therefore, the number S of segments 16 provided in the commutator 143 of this embodiment is set to “24”.

  The eight teeth 151 to 158 are integrally formed at positions that are equiangularly spaced in the circumferential direction with respect to the core back 20 (45 ° intervals in the present embodiment), and each of the teeth 151 to 158 is the first embodiment. It has the same shape as each of the teeth 21 to 25. That is, a pair of branch teeth portions 26a and 26b similar to those of the first embodiment are provided at the tip portions of the teeth 151 to 158, and the teeth 151 to 158 are more radial than the branch teeth portions 26a and 26b. A portion on the proximal end side that is the inner side is an inner winding portion 27. Further, in each of the teeth 151 to 158, an extending portion 28 is integrally formed at the distal end portion of the branching tooth portions 26a and 26b that make a pair. The armature core 142 has an inner slot 31 between the teeth 151 to 158 adjacent in the circumferential direction, and an outer slot 32 between the branching tooth portions 26a and 26b forming a pair. Since the armature core 142 of this embodiment includes eight teeth 151 to 158, the armature core 142 includes eight inner slots 31 and eight outer slots 32. In the armature core 142, the inner slot 31 and the outer slot 32 are formed at positions shifted in the circumferential direction, and each outer slot 32 is located between the inner slots 31 adjacent in the circumferential direction. In the present embodiment, as shown in FIG. 10, teeth numbers “1” to “16” are sequentially attached to the branch teeth portions 26 a and 26 b of the eight teeth 151 to 158 in the circumferential direction.

  As shown in FIGS. 9 and 10, the armature core 142 configured as described above is wound with a plurality of armature coils by winding the conductive wire 41. The plurality of armature coils are wound around eight inner layer coils 162a to 162h wound around the inner winding portion 27, which is a base end portion side of each of the teeth 151 to 158, and the branching tooth portions 26a and 26b. The eight outer layer coils 163a to 163h are rotated. In FIG. 10, the inner layer coils 162 a to 162 h are indicated by middle lines, and the outer layer coils 163 a to 163 h are indicated by thick lines.

  In the armature core 142, first, inner layer coils 162a to 162h are wound around the inner winding portions 27 of the teeth 151 to 158 in a concentrated manner. Thereafter, the two branch teeth portions 26a and 26b adjacent in the circumferential direction of the teeth 151 to 158 adjacent in the circumferential direction (that is, the branch teeth portion 26a of one tooth in the two adjacent teeth and the branch teeth portion 26a are adjacent to each other). The outer layer coils 163a to 163h are wound in distributed winding on the branching tooth portion 26b) of the other tooth. All the inner layer coils 162a to 162h have the same winding direction, and the outer layer coils 163a to 163h are wound in the same direction as the inner layer coils 162a to 162h. Further, the inner layer coils 162a to 162h wound earlier and the outer layer coils 163a to 163h wound later are formed at positions shifted from each other in the radial direction so as not to overlap in the axial direction. Further, the center in the circumferential direction of each inner layer coil 162a to 162h and the center in the circumferential direction of each outer layer coil 163a to 163h are shifted from each other in the circumferential direction of the armature core 142, and alternately and circumferentially in the circumferential direction. It is equiangularly spaced.

  The winding start ends of the eight inner layer coils 162a to 162h are respectively connected to every other eight segments 16 in the circumferential direction, and the winding end ends of the inner layer coils 162a to 162h are Each of the inner layer coils 162a to 162h is connected to the winding start end portion of the outer layer coils 163a to 163h at a position advanced about 120 ° in the circumferential direction (about 120 ° clockwise from each tooth in FIG. 9). Accordingly, the inner layer coils 162a to 162h are coupled in series with the outer layer coils 163a to 163h, respectively, located at positions separated by about 120 ° in the circumferential direction. Furthermore, the end portions of the winding ends of the outer layer coils 163a to 163h are respectively connected to the teeth 151 to 158 having one branch tooth portion 26a out of the two branch teeth portions 26a and 26b around which the outer layer coils 163a to 163h are wound. The winding start end portions of the wound inner layer coils 162a to 162h are connected to the connected segments 16, respectively. Accordingly, every eight segments 16 in the circumferential direction (that is, segment numbers “2”, “5”, “8”, “11”, “14”, “17”, “20”, “23”). The segments 16) are connected to the winding start ends of the inner layer coils 162a to 162h and the winding end ends of the outer layer coils 163a to 163h one by one.

  In the armature 141 of the present embodiment, the inner layer coil and the outer layer coil (for example, the inner layer coil 162a and the outer layer coil 163d) coupled in series are spaced between the magnets having the same center in the circumferential direction and the same magnetic pole. The gap is close to 120 ° (the gap between the south pole magnets 132a, 132c, 132e (or the gap between the north pole magnets 132b, 132d, 132f)). FIG. 9 shows a center line X1 passing through the center in the circumferential direction of the upper south pole magnet 132a, a center line X2 passing through the center in the circumferential direction of the lower right south pole magnet 132c, and the circumferential direction of the inner layer coil 162a. A center line Y1 passing through the center of the outer layer coil 163 and a center line Y2 passing through the center in the circumferential direction of the outer layer coil 163d are illustrated.

  As shown in FIG. 9, in the DC motor M3 of the present embodiment, the inner layer coils 162a to 162h are wound in a concentrated manner around the inner winding portions 27 of the teeth 151 to 158, as in the first embodiment. Therefore, the inner layer coils 162a to 162h do not overlap in the axial direction on both sides of the armature core 142 in the axial direction. The outer layer coils 163a to 163h are wound around two branch teeth portions 26a and 26b adjacent in the circumferential direction, respectively, but the outer layer coils 163a to 163h are wound around different branch tooth portions 26a and 26b. Therefore, the outer layer coils 163 a to 163 h adjacent in the circumferential direction do not overlap in the axial direction on both sides in the axial direction of the armature core 142. Further, since the outer layer coils 163a to 163h are wound around the teeth 151 to 158 on the radially outer side than the inner layer coils 162a to 162h, the outer layer coils 163a to 163h and the inner layer coils 162a to 162h are displaced in the radial direction. The both sides of the child core 142 in the axial direction do not overlap each other in the axial direction. For these reasons, the coil end portions 164 of the inner layer coils 162a to 162h (the portions projecting in the axial direction from the axial end surface of the armature core 142 in each of the inner layer coils 162a to 162h) and the coils of the outer layer coils 163a to 163h. Since the end portion 165 (the portion protruding in the axial direction from the end surface in the axial direction of the armature core 142 in each of the outer layer coils 163a to 163h) does not overlap in the axial direction, the coil end portions 164 and 165 are made smaller in the axial direction. can do.

  Here, FIG. 11 shows a cross-sectional view of the DC motor M11 in which both the inner layer coil and the outer layer coil are concentrated winding, and FIG. In addition, in DC motor M11 shown in FIG.11 and FIG.12, about the structure same as DC motor M3 of this embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  As shown in FIGS. 11 and 12, the armature core 172 of the armature 171 constituting the DC motor M <b> 11 has eight teeth extending radially outward from the outer peripheral surface of the cylindrical core back 20. 181 to 188 are provided. Inner layer coils 191a to 191h are wound around the base end portions of the teeth 181 to 188, respectively, and outer layer coils 192a to 192h are wound around the distal end portions of the teeth 181 to 188, respectively. Yes. And the end part of the winding start of the eight inner layer coils 191a to 191h is connected to every other eight segments 16 in the circumferential direction, and the end part of the winding end of the inner layer coils 191a to 191h is The windings are respectively connected to the winding start ends of the outer layer coils 192a to 192h at positions advanced by 120 ° in the circumferential direction from the inner layer coils 191a to 191h. Accordingly, the inner layer coils 191a to 191h are coupled in series with the outer layer coils 192a to 192h, respectively, located 120 ° apart in the circumferential direction. Furthermore, the winding end ends of the outer layer coils 192a to 192h are connected to the segments 16 connected to the winding start ends of the inner layer coils 191a to 191h wound around the same teeth 151 to 158, respectively. . Accordingly, every eight segments 16 in the circumferential direction (that is, segment numbers “2”, “5”, “8”, “11”, “14”, “17”, “20”, “23”). The segment 16) is connected to one end of the inner layer coils 191a to 191h and one end of the outer layer coils 192a to 192h.

  In the DC motor M11, the anode brush 14 is disposed at a position corresponding to the circumferential center of the N-pole magnet 132d, and the cathode brush 15 is disposed at a position corresponding to the circumferential center of the S-pole magnet 132a. Further, the three segments 16 arranged at intervals of 120 ° are short-circuited to each other by the short-circuit member 145 so as to have the same potential. Therefore, each inner layer coil 191a to 191h is rectified when it is arranged at a position where the center in the circumferential direction coincides with the center in the circumferential direction of each magnet 132a to 132f. That is, rectification of the inner layer coils 191a to 191h is performed at two locations facing in the radial direction.

  In general, in a DC motor that performs rectification at two locations facing each other in the radial direction, it is known that the magnetic excitation force due to current fluctuation tends to concentrate at two locations corresponding to the two armature coils that are being rectified. ing. It is also known that when the armature coil being rectified and the armature coil to be rectified next are coupled in series, this magnetic excitation force can be dispersed to reduce the armature vibration. In the DC motor M11 shown in FIG. 11, the inner layer coil 191a that is being rectified and the outer layer coil 192d that is rectified next to the inner layer coil 191a are coupled in series to reduce the vibration of the armature 171. It is illustrated.

  However, since the number N of the teeth 181 to 188 in the DC motor M11 is “8”, the tooth 181 around which the inner layer coil 191a being rectified in FIG. 11 is wound and the outer layer coupled in series with the inner layer coil 191a. Since the tooth 184 around which the coil 192d is wound forms 135 °, the angle formed by the center lines Y11 and Y12 passing through the centers in the circumferential direction of the coils 191a and 192d is 135 °. Furthermore, an angle formed between the south pole magnet 132a radially facing the inner layer coil 191a and the south pole magnet 132c radially facing the outer layer coil 192d (that is, passes through the center in the circumferential direction of the magnets 132a and 132c). The angle formed by the center lines X11 and X12 is 120 °. Therefore, the circumferential center of the outer layer coil 192d coupled in series with the inner layer coil 191a that is being rectified and then subjected to rectification is the center of the circumferential direction of the south pole magnet 132c that is radially opposed to the outer layer coil 192d. It will deviate from. Therefore, the DC motor M11 has a problem that the vibration reduction effect is reduced.

  On the other hand, as shown in FIG. 9, in the DC motor M3 of the present embodiment, a pair of branch teeth portions 26a and 26b branched to be spaced apart in the circumferential direction are provided at the tips of the teeth 151 to 158, respectively. It has been. The outer layer coils 163a to 163h are wound around the branch tooth portions 26a and 26b so as to straddle two adjacent teeth in the circumferential direction. Deviation in the circumferential direction with respect to ~ 162h. Therefore, for example, in FIG. 9, the outer layer coil 163c connected in series with the inner layer coil 162a being rectified and then rectified is wound around the branch tooth portions 26a and 26b so as to straddle the teeth 153 and 154. The center in the circumferential direction is located between the teeth 153 and 154. Therefore, compared to the center in the circumferential direction of the outer layer coil 192d in the DC motor M11 shown in FIG. 11, the center in the circumferential direction of the outer layer coil 163c in the DC motor M3 is the circumferential direction of the S-pole magnet 132c opposed in the radial direction. Approach the center. As a result, the DC motor M3 of the present embodiment has a greater effect of reducing the vibration of the rotating shaft 11 of the armature 141 than the DC motor M11.

As described above, according to the third embodiment, in addition to the functions and effects of (1), (2), and (4) to (6) of the first embodiment, the following functions and effects are provided.
(1) In the DC motor M3, the number P of magnetic poles is P = 6, the number N of teeth 151 to 158 is N = 8, and the number S of segments is S = 24. Therefore, in the DC motor M3 including the inner layer coils 162a to 162h and the outer layer coils 163a to 163h, the radial force acting on the armature core 142 when the DC motor M3 is driven can be extremely reduced (Japanese Patent Laid-Open No. 2004-2004). 88916, JP2003-259582A), vibration in the DC motor M3 can be further reduced.

  (2) The magnetic excitation force due to current fluctuation can be dispersed in four locations, and the vibration of the armature 141 during rectification can be further reduced. Further, the deformation mode of the yoke housing 3 can be set to a higher-order deformation mode than the secondary mode, and resonance of the yoke housing 3 can be easily avoided.

(Fourth embodiment)
Hereinafter, a fourth embodiment of the present invention will be described with reference to the drawings. In the fourth embodiment, the same components as those in the first to third embodiments are denoted by the same reference numerals and description thereof is omitted.

  FIG. 13 shows a schematic diagram of a DC motor M4 of the fourth embodiment. The DC motor M4 is different from the DC motor M3 of the third embodiment in the configuration of the outer layer coil that constitutes the armature 201.

  As with the second embodiment, eight inner layer coils 202a to 202h and eight outer layer coils 203a to 203h are wound around the armature core 82. Then, the outer layer coils 203a to 203h wound around the two branch tooth portions 26a and 26b adjacent in the circumferential direction so as to straddle the teeth adjacent in the circumferential direction are wound around the base end side of the branch tooth portions 26a and 26b. The inner coils 211a to 211h are rotated and the outer coils 212a to 212h are wound around the distal ends of the branch tooth portions 26a and 26b. In FIG. 14, the inner layer coils 202 a to 202 h are indicated by a middle line, the inner coils 211 a to 211 h are indicated by a one-dot chain line, and the outer coils 212 a to 212 h are indicated by a thick line. Moreover, in FIG. 14, each inner layer coil 202a-202h formed by winding a conducting wire around each inner winding part 27 several times is simplified and illustrated.

  As shown in FIGS. 13 and 14, first, the inner layer coils 202 a to 202 h are wound on the armature core 142 around the inner winding portions 27 of the teeth 151 to 158 by concentrated winding. All the inner layer coils 202a to 202h have the same winding direction. Thereafter, branch teeth 26a and 26b adjacent in the circumferential direction of teeth 151 to 158 adjacent in the circumferential direction (that is, the branch teeth 26a of one of the two adjacent teeth and the other adjacent to the branch teeth 26a) The inner coils 211a to 211h are respectively wound by distributed winding on the base end side portion of the branch tooth portion 26b). At this time, each inner coil 211a-211h is wound in the opposite direction to each inner layer coil 202a-202h. Thereafter, the outer coils 212a to 212h are respectively wound by distributed winding around the distal end portions of the two branch tooth portions 26a and 26b around which the inner coils 211a to 211h are wound. At this time, the outer coils 212a to 212h are wound in the same direction as the inner coils 211a to 211h (that is, the direction opposite to the inner layer coils 202a to 202h). In addition, the inner layer coils 202a to 202h wound earlier and the outer layer coils 203a to 203h wound later (that is, the inner coils 211a to 211h and the outer coils 212a to 212h) are shifted from each other in the radial direction. It is formed so that it does not overlap in the axial direction. Furthermore, the center in the circumferential direction of each inner layer coil 202a to 202h and the center in the circumferential direction of each outer layer coil 203a to 203h are shifted from each other in the circumferential direction of the armature core 142, and alternately in the circumferential direction and in the circumferential direction. It is equiangularly spaced. Further, the electric resistance of each inner layer coil 202a to 202h is equal to the sum of the electric resistance of one inner coil of each of the inner coils 211a to 211h and the electric resistance of one outer coil of each of the outer coils 212a to 212h. ing.

  And the end part of the winding start of each inner coil 211a-211h is connected to the eight segments 16 every two in the circumferential direction, respectively, and the end part of the winding end of each inner coil 211a-211h is each The inner coils 211a to 211h are respectively connected to the winding start ends of the inner layer coils 202a to 202h located at a position approximately equal to the distance between adjacent magnets 132a to 132f (that is, about 60 °). Further, the winding end ends of the inner layer coils 202a to 202h are respectively connected to the winding start end portions of the outer coils 212a to 212h located at about 60 ° apart from the inner layer coils 202a to 202h. And the end part of the winding end of each outer coil 212a-212h is each connected to the segment 16 to which the end part of the winding start of each inner coil 211a-211h wound around the same branch teeth part 26a, 26b was connected. ing. Accordingly, every eight segments 16 in the circumferential direction (that is, segment numbers “2”, “5”, “8”, “11”, “14”, “17”, “20”, “23”). In the segment 16), the winding start ends of the inner coils 211a to 211h and the winding end ends of the outer coils 212a to 212h are connected one by one.

  As described above, in the armature 201 of the present embodiment, each of the inner layer coils 202a to 202h and one of the teeth on both sides in the circumferential direction of the teeth 151 to 158 around which the inner layer coils 202a to 202h are wound are provided. Three coils each of the wound inner coils 211a to 211h and the outer coils 212a to 212h wound on the other tooth are coupled in series. The three coils coupled in series are arranged at intervals substantially equal to the interval between adjacent magnets 132a to 132f (ie, about 60 °). Thereby, in DC motor M4, the magnetic excitation force which acts on armature 201 at the time of rectification of each inner layer coil 202a-202h, each inner coil 211a-211h, and each outer coil 212a-212h is distributed to six places. be able to. For example, as shown in FIG. 13, when the inner layer coil 202a is diametrically opposed to the south pole magnet 132a and the inner layer coil 202a is rectified, both the inner layer coil 202a and the inner layer coil 202a The excitation force is distributed at a total of six locations on both sides in the radial direction of the inner coil 211g coupled in series and on both sides in the radial direction of the outer coil 212b coupled in series with the inner layer coil 202a. Therefore, the vibration of the armature 201 due to the magnetic excitation force due to the electric fluctuation is further reduced.

  As described above, according to the fourth embodiment, the effects (1), (2), (4) to (6) of the first embodiment and the action (1) of the third embodiment. In addition to the effects, it has the following effects.

  (1) Magnetic excitation force due to current fluctuation can be dispersed in six locations, and vibration of the armature 201 during rectification can be further reduced. Further, the deformation mode of the yoke housing 3 can be set to a higher-order deformation mode than the secondary mode, and resonance of the yoke housing 3 can be easily avoided.

(Fifth embodiment)
Hereinafter, a fifth embodiment of the present invention will be described with reference to the drawings. In the fifth embodiment, the same components as those in the first to fourth embodiments are denoted by the same reference numerals and description thereof is omitted.

  FIG. 15 is a schematic diagram in which the DC motor M9 of the fifth embodiment is developed in a planar shape. The DC motor M9 of this embodiment has substantially the same configuration as the DC motor M2 of the second embodiment. Specifically, as shown in FIG. 16, the DC motor M9 includes a stator 1 and an armature 81 that is rotatably disposed inside the stator 1. Since the stator 1 has four magnets 4a to 4d fixed to the inner peripheral surface of the yoke housing 3, the number P of the magnetic poles of the DC motor M9 is “4”. The four magnets 4a to 4d are provided at equiangular intervals in the circumferential direction, and the opening angle θ1 of each magnet 4a to 4d (the circumferential direction of each magnet 4a to 4d with the rotation center of the rotating shaft 11 as the center). The angle corresponding to this range is 90 °.

  The rotary shaft 11 constituting the armature 81 is rotatably supported at both ends in the axial direction by the stator 1, and the rotary shaft 11 is provided in the DC motor M <b> 2 of the second embodiment. The same armature core 82 as the armature core 82 is fixed so as to be integrally rotatable. The armature core 82 includes six teeth 91 to 96 each having a pair of branch tooth portions 26a and 26b at the tip portions thereof, so that the inner layer coils 102a to 102f are wound through the conductor 41. Six inner slots 31 and six outer slots 32 for forming the outer layer coils 103a to 103f through the conducting wires 41 are provided. That is, the armature core 82 includes a total of 12 slots for winding the armature coils (that is, the inner layer coils 102a to 102f and the outer layer coils 103a to 103f), and the total number M of slots is the number of magnetic poles P ( That is, it is three times “4”).

  As shown in FIGS. 15 and 16, the inner layer coils 102 a to 102 f wound around the armature core 82 are concentratedly wound around the inner winding portions 27, which are the base end sides of the teeth 91 to 96, respectively. It is wound by. Further, the outer layer coils 103a to 103f wound around the armature core 82 are respectively wound around the two branch teeth portions 26a and 26b adjacent in the circumferential direction, but the outer layer coils 103a to 103f are different from each other. Since it is wound around the branching tooth portions 26 a and 26 b, the outer layer coils 103 a to 103 f adjacent in the circumferential direction do not overlap in the axial direction on both sides in the axial direction of the armature core 82. Furthermore, since the outer layer coils 103a to 103f are wound around the teeth 91 to 96 on the radially outer side than the inner layer coils 102a to 102f, the outer layer coils 103a to 103f and the inner layer coils 102a to 102f are displaced in the radial direction. The both sides of the child core 82 in the axial direction do not overlap each other in the axial direction. Therefore, the coil pitch P1 of each of the inner layer coils 102a to 102f and each of the outer layer coils 103a to 103f (an angle corresponding to the circumferential range of each coil around the rotation center of the rotating shaft 11) is 60 °. In FIG. 16, only the outer layer coil 103a is shown as a representative.

  As shown in FIGS. 15 and 17, the commutator 83 fixed to the rotary shaft 11 and constituting the armature 81 includes twelve segments 16 arranged in parallel in the circumferential direction. The number S is three times the number P of magnetic poles (that is, “4”). Each segment 16 is connected to one end portion of each of the inner layer coils 102a to 102f wound around the inner winding portion 27 of the armature core 82 and wound around the branch tooth portions 26a and 26b. One end of each of the outer layer coils 103a to 103f is connected.

  Two anode-side brushes 501 and two cathode-side brushes 502 are arranged on the outer periphery of the commutator 83. The anode-side brush 501 and the cathode-side brush 502 having a substantially quadrangular prism shape are alternately arranged in the circumferential direction, and the front end surface on the commutator 83 side is in sliding contact with the segment 16 provided on the outer periphery of the commutator 83. Pressing contact is possible. In addition, in the anode side brush 501 and the cathode side brush 502, the front end surface becomes a slidable contact portion that slidably contacts the segment 16 of the commutator 83.

  Each anode-side brush 501 and each cathode-side brush 502 have a width w1 in the circumferential direction that is half the width w2 in the circumferential direction of the segment 16. Each anode-side brush 501 is disposed at a position corresponding to the approximate center in the circumferential direction of the N-pole magnets 4a and 4c, and each cathode-side brush 502 is arranged in the circumferential direction of the S-pole magnets 4b and 4d. Are arranged at positions corresponding to the approximate center of each. Usually, the anode-side brush and the cathode-side brush are arranged at normal positions where the center in the circumferential direction of each brush is located on the magnetic pole center line of the magnet (a straight line extending in the radial direction through the center in the circumferential direction of the magnet). However, in the DC motor M9 of the present embodiment, the anode side brush 501 and the cathode side brush 502 are arranged along the circumferential direction from the normal position on the magnetic pole center lines X3 to X6 passing through the circumferential centers of the magnets 4a to 4d. Are shifted in opposite directions. That is, the anode-side brush 501 disposed corresponding to the N-pole magnet 4a disposed on the upper side in FIG. 17 is shifted in the clockwise direction from the normal position on the magnetic pole center line X3 of the magnet 4a. In FIG. 17, the anode-side brush 501 disposed corresponding to the N-pole magnet 4c disposed on the lower side is disposed to be shifted clockwise from the normal position on the magnetic pole center line X5 of the magnet 4c. . The end faces on the counterclockwise direction side of these two anode side brushes 501 are located on the magnetic pole center lines X3 and X5, respectively. On the other hand, the cathode-side brush 502 arranged corresponding to the south pole magnet 4b arranged on the right side in FIG. 17 is arranged to be shifted counterclockwise from the normal position on the magnetic pole center line X4 of the magnet 4b. In addition, the cathode-side brush 502 disposed corresponding to the S-pole magnet 4d disposed on the left side in FIG. 17 is shifted from the normal position on the magnetic pole center line X6 of the magnet 4d in a counterclockwise direction. Yes. The end faces on the clockwise side of these two cathode-side brushes 502 are located on the magnetic pole center lines X4 and X6, respectively. Accordingly, when current is supplied to the armature 81 from the anode side brush 501 and the cathode side brush 502 and the armature 81 is rotated, the anode side brush 501 and the cathode side brush 502 are rotated with the rotation of the armature 81. The rectification is alternately performed in step.

  Here, FIG. 18 and FIG. 20 show a schematic diagram of a conventional DC motor M12 in which armature coils are wound by distributed winding, and FIG. 19 shows a schematic diagram in which the DC motor M12 is developed in a planar shape. Show. As shown in FIGS. 18 to 20, the DC motor M12 includes a stator 603 formed by fixing four magnets 602 to the inner peripheral surface of a substantially cylindrical yoke housing 601, and the stator 603 inside the stator 603. And an armature 604 arranged to be rotatable with respect to the stator 603. The armature core 606 fixed to the rotating shaft 605 of the armature 604 extends radially outward from the outer peripheral surface of the core back 606a and the cylindrical core back 606a fitted on the rotating shaft 605. Twelve teeth 606b are integrally formed. The armature core 606 has a total of twelve slots 606c between teeth 606b adjacent in the circumferential direction. Twelve armature coils 607 are wound around the armature core 606 by distributed winding. Each armature coil 607 is wound around three teeth 606b so as to straddle a plurality of slots. FIG. 19 shows only two of the twelve armature coils 607 as representatives, and FIG. 20 shows only one of the twelve armature coils 607 as representatives. Further, a commutator 609 having 12 segments 608 arranged in parallel in the circumferential direction is fixed to the rotating shaft 605, and one end of two armature coils 607 is provided in each segment 608. It is connected. Further, around the commutator 609, two anode-side brushes 701 and two cathode-side brushes for supplying current to the armature coil 607 are arranged. The anode-side brush 701 and the cathode-side brush 702 are formed so that the circumferential width thereof is equal to the circumferential width of the segment 608, and their tip surfaces are pressed and slidably contacted with the segment 608 of the commutator 609. Yes. The anode-side brush 701 and the cathode-side brush 702 are alternately arranged in the circumferential direction, and on a magnetic pole center line (shown by a one-dot chain line in FIG. 18) passing through the centers of the four magnets 602 in the circumferential direction. The brushes 701 and 702 are arranged at normal positions where the circumferential centers are arranged.

  In such a conventional DC motor M12, the number of slots and the number of armature coils are “12”, similarly to the DC motor M9 of the present embodiment. Further, as shown in FIG. 20, the open angle θ2 of the magnet 602 in the DC motor M12 is 90 ° as in the DC motor M9. However, in this DC motor M12, since each armature coil 607 is wound around three teeth 606b, each coil pitch P2 of each armature coil 607 (each centered on the rotation center of the rotating shaft 11). The angle corresponding to the circumferential range of the coil is 90 °. That is, the DC motor M9 of the present embodiment has a smaller coil pitch P1 (see FIG. 16) than the conventional DC motor M12 provided with the armature coil 607 wound by distributed winding. Therefore, in the conventional DC motor M12, an induced voltage is generated in the rectifying section as shown in FIG. 23A and insufficient rectification occurs as shown in FIG. 23B. However, in the DC motor M9 of the present embodiment, As shown in FIG. 22A, the generation of the induced voltage is suppressed in the rectifying section, and as a result, the occurrence of insufficient rectification is suppressed as shown in FIG.

  Further, as shown in FIG. 21, when the total number M of slots is divisible by the number P of magnetic poles, rectification is simultaneously performed by the anode side brush and the cathode side brush, so that the current ripple (current waveform) is reduced. It can be seen that the number of peaks is small and the current ripple tends to increase (the fluctuation of the current waveform increases). When the current ripple increases, the vibration and noise of the DC motor during driving increase.

  In the DC motor M9 of this embodiment (corresponding to a portion surrounded by a thick line in FIG. 21), the number P of magnetic poles is “4”, the total number M of slots is “12”, and the total number M of slots. Is divisible by the number P of magnetic poles. However, in the DC motor M9 of the present embodiment, the anode side brush 501 and the cathode side brush 502 are arranged along the circumferential direction from the normal position on the magnetic pole center lines X3 to X6 passing through the circumferential centers of the magnets 4a to 4d. By being shifted in the opposite direction, the anode side brush 501 and the cathode side brush 502 are configured to alternately perform rectification. Therefore, even if the total number M of slots is divisible by the number P of magnetic poles, as can be seen from the current waveforms shown in FIGS. 15 and 19, the DC motor M9 has a current larger than that of the conventional DC motor M12. Since the amount of change in value is kept small and the current ripple is reduced, the generation of vibration and noise during driving is suppressed.

As described above, according to the fifth embodiment, the following functions and effects are provided in addition to the functions and effects similar to (1) to (6) of the first embodiment.
(1) The DC motor M9 has a configuration in which the total of the inner slots 31 and the outer slots 32 (that is, the total number M of slots) is divisible by the number P of magnetic poles, but rectification by the anode side brush 501 and rectification by the cathode side brush 502 Are performed alternately. Therefore, the amount of change in the current value during driving can be reduced, and vibration and magnetic noise can be reduced as compared with the DC motor M12 configured to rectify simultaneously in the anode side brush 701 and the cathode side brush 702. it can.

Each embodiment of the present invention may be modified as follows.
In the DC motor M9 of the fifth embodiment, the width w1 in the circumferential direction of the anode side brush 501 and the cathode side brush 502 (the width in the circumferential direction of the sliding contact portion in sliding contact with the segment 16 in each brush) is the segment 16 Is set to a half width of the circumferential width w2. However, the anode-side brush 501 and the cathode-side brush 502 are arranged so as to be shifted in opposite directions along the circumferential direction from the normal positions on the magnetic pole center lines X3 to X6 passing through the circumferential centers of the magnets 4a to 4d. If the rectification is alternately performed in the anode side brush 501 and the cathode side brush 502 as the armature 81 rotates, the circumferential width w1 is half the circumferential width w2 of the segment 16. It may be set to a smaller value, or may be set to a value larger than a half width of the circumferential width w2 of the segment 16. In this way, as in the fifth embodiment, since the rectification is alternately performed between the anode side brush 501 and the cathode side brush 502 as the armature 81 rotates, the current ripple is smaller than that of the conventional motor. Since the torque ripple is suppressed and the generation of vibration and noise during driving can be suppressed. Further, the anode-side brush 501 and the cathode-side brush 502 are arranged so as to be shifted from the normal position in opposite directions along the circumferential direction so that the anode-side brush 501 and the cathode-side brush 502 are alternately rectified. In this case, if the circumferential width of the slidable contact portion slidably contacting the segment 16 in the anode side brush 501 and the cathode side brush 502 is less than half of the circumferential width w2 of the segment 16, in addition to suppressing generation of vibration and noise. Thus, the torque can be increased. Furthermore, if the circumferential width of the sliding contact portion of the anode side brush 501 and the cathode side brush 502 is half of the circumferential width w2 of the segment 16, the generation of vibration and noise can be suppressed and the torque can be increased. In addition, when the anode side brush 501 and the cathode side brush 502 are configured to alternately rectify as described above, the supply current can be maximized.

  24 and 25, in the DC motor M9 of the fifth embodiment, the anode brush 501 and the cathode brush 502 are arranged on one side in the circumferential direction of the anode brush 501 and the cathode brush 502. A high resistance brush 801 having a higher resistance may be arranged. More specifically, each high resistance brush 801 is adjacent to the tip surface (sliding contact portion) of each anode side brush 501 and each cathode side brush 502 in the circumferential direction, and on the magnetic pole center lines X3 to X6 of the magnets 4a to 4d. The adjacent brushes 501 and 502 from the normal position are shifted in the direction opposite to the shifted direction. In this way, it is possible to suppress the occurrence of sparks when each anode-side brush 501 and each cathode-side brush 502 are in contact with the segment 16 and separated.

  In a DC motor in which the total number M of slots is divisible by the number P of magnetic poles like the DC motor M9 of the fifth embodiment, the inner layer coil being rectified and the outer layer coil to be rectified next are connected in series. Also good. If it does in this way, the vibration of an armature can be reduced more. Further, in the DC motor having the same configuration, when the anode side brush and the cathode side brush are shifted from the normal position on the magnetic pole center line passing through the center in the circumferential direction of the magnet and shifted in opposite directions along the circumferential direction, Since the rectification by the side brush and the rectification by the cathode side brush are alternately performed, the amount of change in the current value during driving can be reduced, and vibration and magnetic noise can be further reduced. Furthermore, the high resistance brush which is adjacent to the front end surface (sliding contact portion) of each anode-side brush and each cathode-side brush and which is arranged by shifting each adjacent brush in a direction opposite to the direction shifted from the normal position. By providing, it is possible to suppress the occurrence of sparks when the brushes come into contact with the segments and when they are separated.

  -In the said 4th Embodiment, each inner layer coil 202a-202h and the inner coil wound by one tooth among the teeth of both sides of the circumferential direction of teeth 151-158 in which each inner layer coil 202a-202h was wound Three coils of 211a to 211h and outer coils 212a to 212h wound around the other tooth are coupled in series. However, the combination of the inner coil and the outer coil coupled in series to each of the inner layer coils 202a to 202h is not limited to that of the fourth embodiment. As shown in FIG. 26, the inner layer coil 202a, the inner coil 211c at a position about 120 ° away from the inner layer coil 202a on one side in the circumferential direction, and the position about 120 ° away from the other side in the circumferential direction. The outer coil 212f may be coupled in series. In this case, when the S-pole magnet 132a and the inner-layer coil 202a face each other in the radial direction and the inner-layer coil 202a is rectified, the inner coil 211c and the outer coil 212f are in the radial direction with the S-pole magnets 132c and 132e. opposite. In FIG. 26, only the inner layer coil 202a, the inner coil 211c, and the outer coil 212f that are coupled in series are shown as representatives, but the remaining inner layer coils 202b to 202h are similar to the inner layer coils 202b to 202h. The inner coils 211a, 211b, 211d to 211h and the outer coils 212a to 212e, 212g, and 212h that are in the positional relationship are coupled in series. In this case, the inner coils 211a to 211h and the outer coils 212a to 212h are wound in the same direction as the inner layer coils 202a to 202h. Further, the winding start end of each of the inner coils 211a to 211h is connected to every second segment 16 of the 24 segments 16 of the commutator 143, and the winding end of each of the inner coils 211a to 211h. Is connected to the winding start end portions of the inner layer coils 202a to 202h located at a position approximately 120 ° away from the inner coils 211a to 211h in the circumferential direction. Further, the winding end ends of the respective inner layer coils 202a to 202h are connected to the winding start end portions of the outer coils 212a to 212h located at a position approximately 120 ° apart from each inner layer coil 202a to 202h in the circumferential direction. The winding end ends of the outer coils 212a to 212h are respectively connected to the segments 16 to which the winding start ends of the inner coils 211a to 211h wound around the same branch tooth portions 26a and 26b are connected. Even if it does in this way, similarly to the said 4th Embodiment, a magnetic exciting force can be disperse | distributed to six places.

  -When each outer layer coil 203a-203h is comprised from two coils, each inner coil 211a-211h and each outer coil 212a-212h like the said 4th Embodiment, inner layer coil 202a-202h and outer layer coil 203a- The connection mode 203h is not limited to that of the fourth embodiment. For example, as shown in FIG. 27, inner layer coils 202a to 202h and outer layer coils 203a to 203h may be formed. In the direct current motor M5 shown in FIG. 27, as shown in FIG. It is connected to every two segments 16 every eight in the circumferential direction. Accordingly, every second segment 16 (ie, segment 16 with segment numbers “2”, “5”, “8”, “11”, “14”, “17”, “20”, “23”) The winding start ends and the winding end ends of the inner layer coils 202a to 202h are connected one by one. Moreover, as shown in FIG. 29, the inner coils 211a to 211h and the outer coils 212a to 212h are wound in the opposite direction to the inner layer coils 202a to 202h. The winding ends of the inner coils 211a to 211h are arranged at every other segment 16 (ie, segment numbers “2”, “5”, “8”, “11”, “14”, “17”). , “20”, “23” segments 16), and the end portions of the winding ends of the inner coils 211a to 211h are outside the inner coils 211a to 211h at a position spaced 135 ° in the circumferential direction. The coils 212a to 212h are connected to the winding start ends. Furthermore, the winding end ends of the outer coils 212a to 212h are respectively connected to the segments 16 to which the winding start ends of the inner coils 211a to 211h wound around the same branch tooth portions 26a and 26b are connected. . Even if it does in this way, similarly to the said 4th Embodiment, a magnetic exciting force can be disperse | distributed to six places.

  For example, in the DC motor M6 shown in FIG. 30, the inner coils 211a to 211h and the outer coils 212a to 212h are wound in the same manner as in the example shown in FIG. And as shown in FIG. 31, each inner layer coil 202a-202h is connected to the two segments 16 adjacent to each other in the circumferential direction at the winding start and winding end portions. Even if it does in this way, similarly to the said 4th Embodiment, a magnetic exciting force can be disperse | distributed to six places.

  In the second embodiment, the inner layer coils 102a to 102f and the outer layer coils 103a to 103f are wound around the armature core 82 using two flyers. However, by connecting the ends of the inner layer coils 102a to 102f and the outer layer coils 103a to 103f to the segment 16 as shown in FIG. 32, all the inner layer coils are connected by one conductor 41 using one flyer. 102 a to 102 f and outer layer coils 103 a to 103 f can be wound around the armature core 82. In this case, after winding all the inner layer coils 102a to 102f, the outer layer coils 103a to 103f are wound. More specifically, after the conductive wire 41 is connected to the segment 16 with the segment number “1”, the inner layer coil 102 a is wound around the inner winding portion 27 of the tooth 91 and connected to the segment 16 with the segment number “2”. . Next, the conductive wire 41 forms an inner layer coil 102f that is magnetically equivalent to the branch tooth portion 26b having the tooth number “2” and the outer layer coil 103a having the tooth number “3”. At this time, since the inner layer coil 102f has the opposite magnetic pole to the outer layer coil 103f, the winding direction is opposite to that of the outer layer coil 103f. Note that the arrows shown in FIG. 32 indicate the winding directions of the inner layer coils 102a to 102f and the outer layer coils 103a to 103f. Thereafter, the inner layer coils 102b, 102d, 102c, and 102e are sequentially formed by the conductive wire 41, and each time the inner layer coils 102b, 102d, 102c, and 102e are formed, the conductive wire 41 has the segment numbers “3” to “7”. Are connected to the segment 16 in order. And the conducting wire 41 connected to the segment 16 with the segment number “7” forms the outer layer coils 103b, 103d, 103c, 103e, 103a, 103f in order, and the outer layer coils 103b, 103d, 103c, 103e, 103a, Each time 103f is formed, the conducting wire 41 is connected to the segments 16 of segment numbers “8” to “12”, “1” in order. After the winding of the outer layer coil 103f, when the conducting wire 41 is connected to the segment having the segment number “1”, the winding of all the inner layer coils 102a to 102f and the outer layer coils 103a to 103f is completed. Therefore, of the 12 segments, the end portions of the inner layer coil and the outer layer coil are connected to two segments 16 one by one, and half of the remaining ten segments 16 include five segments 16. Two end portions of the inner layer coil are connected to each other, and two end portions of the outer layer coil are connected to the other half of the five segments 16. Thus, if all the inner layer coils 102a to 102f and the outer layer coils 103a to 103f can be continuously wound by one conductor 41, the time required for winding the inner layer coils 102a to 102f and the outer layer coils 103a to 103f can be shortened. Productivity can be improved.

  As described above, in order to wind all the inner layer coils and outer layer coils around the armature core with one conductor 41, the number N of teeth needs to be an odd multiple of the number P of magnetic poles. For example, there is a DC motor in which the number P of magnetic poles is P = 4 and the number N of teeth is N = 12, or a DC motor in which the number P of magnetic poles is P = 6 and the number N of teeth is N = 18. Can be mentioned.

  The end of the inner layer coil is connected to two segments 16 of the plurality of segments 16 through a short-circuit wire that short-circuits the (P / 2) segments 16 located at intervals of (360 / (P / 2)) °. One end of each of the outer and outer layer coils is connected to each other, and one end of two inner layer coils are connected to one half of the remaining segments 16 and one end of the two outer layer coils are connected to the other half of the segments 16. You may comprise so that an edge part may be connected one by one. In the example shown in FIG. 33, the short-circuit lines 301 to 306 short-circuit the two segments 16 positioned at intervals of 180 °. When the inner layer coils 102a to 102f and the outer layer coils 103a to 103f are wound, the conductor 41 connected to the segment 16 having the segment number “1” is formed with the segment number “2” after the inner layer coil 102a is formed. Hooked to the segment 16 of Thereafter, the conductive wire 41 is guided to the segment 16 of the segment number “8” while forming the short-circuit wire 302 and hooked to the segment 16, and then forms the inner layer coil 102 c. Thereafter, the conductor 41 forms the inner layer coils 102c, 102b, 102d, 102f, and 102e and the outer layer coils 103b, 103d, 103c, 103e, 103a, and 103f successively in order while forming the short-circuit wires 301 and 303 to 306. . As a result, one end of the inner layer coil and one end of the outer layer coil are connected to two segments 16 of the twelve segments 16 via the short-circuit lines 301 to 306 one by one, and the remaining ten segments 16 are connected. One of the ends of the two inner layer coils is connected to one half of the five segments 16, and one end of the two outer layer coils is connected to the other half of the five segments 16. If it does in this way, all the inner layer coils 102a-102f and the outer layer coils 103a-103f including the short circuit wires 301-306 can be continuously wound by the one conducting wire 41. FIG. When all the inner layer coils 102a to 102f and the outer layer coils 103a to 103f including the short-circuit wires 301 to 306 are continuously wound by one conductor 41, the inner layer coils 102a to 102f and the outer layer coils 103a to 103f are wound. Since the short-circuit lines 301 to 306 are also formed continuously during the rotation, the number of manufacturing steps is reduced as compared with the case where a separate short-circuit member is formed and disposed. Therefore, the productivity of the DC motor is improved.

  In the second embodiment, the inner layer coils 102a to 102f and the outer layer coils 103a to 103f are wound around the armature core 82 using two flyers. However, the inner layer coils 102a to 102f and the outer layer coils 103a to 103f may be wound around the armature core 82 using three or more flyers. In this case, the end of the inner layer coil and the end of the outer layer coil are connected to n segments (n is an even number of 2 or more) of the plurality of segments 16 included in the commutator one by one, and the rest Half of the segments 16 are connected to one end of two inner layer coils one by one, and the other half of the segments 16 are connected to one end of two outer layer coils. If a plurality of flyers are used simultaneously, the time required for winding 102a to 102f and the outer layer coils 103a to 103f can be shortened, and the productivity of the DC motor M2 can be improved.

  -In each above-mentioned embodiment, all armature cores 12, 82, and 142 are provided with branch tooth parts 26a and 26b in the tip part of teeth. However, the teeth may be configured not to include the branching tooth portions 26a and 26b. In this case, in the DC motor, the number P of magnetic poles is an even number of 4 or more, the number N of teeth is N = 2 × (P ± 2) (N = 12 when P = 4), and the number S of segments 16 is S. = ((P / 2) × N). Each inner layer coil is wound around the proximal end portions of two adjacent teeth. Furthermore, the outer layer coil is wound around the tips of the two adjacent teeth in the center among the four teeth around which the two adjacent inner layer coils are wound. In addition, (P / 2) segments 16 positioned at an interval of (360 / (P / 2)) ° are short-circuited by a short-circuit member, and the same number of circumferential directions as teeth of the plurality of segments 16 are equal. One end of each of the inner layer coil and the outer layer coil is connected to the segments 16 arranged at angular intervals. For example, the armature core 401 of the DC motor M7 shown in FIG. 34 includes 16 teeth 402 that extend radially outward from the outer peripheral surface of the cylindrical core back 20. Inner layer coils 403a to 403h are wound around the proximal ends of two teeth 402 adjacent to each other in the circumferential direction, and four teeth 402 are wound around two adjacent inner layer coils. Outer layer coils 404a to 404h are respectively wound around the tips of two adjacent teeth 402 at the center. The end portions of the inner layer coils 403a to 403h and the outer layer coils 404a to 404h are connected to the segment 16 of the commutator 83 in the same manner as the inner layer coils 162a to 162h and the outer layer coils 163a to 163h of the third embodiment. Yes. Even if it does in this way, similarly to the direct current motor M3 of the said 3rd Embodiment, while suppressing enlargement without reducing an output, it can suppress a vibration. In addition, the number P of magnetic poles is an even number of 4 or more, the number N of teeth is N = 2 × (P ± 2) (N = 12 when P = 4), and the number S of segments is S = ( Since (P / 2) × N), the radial force acting on the armature core 401 when the DC motor M7 is driven can be extremely reduced, and the vibration in the DC motor M7 can be further reduced ( JP, 2004-88916, A, JP, 2003-259582, A).

  In the first to fourth embodiments, each of the DC motors M1 to M4 includes the anode side brush 14 and the cathode side brush 15 one by one. However, the DC motors M <b> 1 to M <b> 4 may include a plurality of anode side brushes 14 and cathode side brushes 15.

  The number P of magnetic poles (magnets) provided in the stators 1, 131 and the number N of teeth provided in the armature cores 12, 82, 142 may be changed as appropriate. However, when N = P ± 2, a greater vibration reduction effect can be obtained (see Japanese Patent Application Laid-Open Nos. 2004-88916 and 2003-259582). For example, the DC motor M8 shown in FIG. 35 includes the stator 1 of the first embodiment and the armature 141 of the third embodiment, so that the number P of magnetic poles is P = 4 and the number of teeth. N is N = 8.

  In each of the above embodiments, the DC motors M1 to M4 and M9 are inner-low DC motors in which the armatures 2, 81, 141, and 201 are arranged inside the stators 1 and 131. However, the present invention may be applied to an outer rotor type DC motor in which an armature is disposed on the outer periphery of the stator.

  4a to 4d, 132a to 132f ... magnets as magnetic poles, 12, 82, 142, 401 ... armature cores, 13, 83, 143 ... commutators, 14, 501 ... anode side brushes as power supply brushes, 15, 502 ... Cathode side brush as power supply brush, 16 ... segment, 21 to 25, 91 to 96, 151 to 158, 402 ... tooth, 26a, 26b ... branch tooth part, 31 ... inner slot, 32 ... outer slot, 42a to 42e, 102a-102f, 162a-162h, 202a-202h, 403a-403f ... inner layer coil as armature coil, 43a-43e, 103a-103f, 163a-163h, 203a-203h, 404a-404f ... outer layer as armature coil Coil, 145 ... short-circuit member, 301 to 306 ... short-circuit wire, 80 ... high-resistance brush, X3~X6 ... magnetic pole center line.

Claims (4)

A plurality of magnetic poles arranged side by side in the circumferential direction;
An armature core having a plurality of teeth arranged side by side in the circumferential direction, the tip of the teeth being opposed to the magnetic pole in the radial direction;
A plurality of armature coils wound around the teeth;
A commutator having a plurality of segments arranged side by side in the circumferential direction and provided so as to be integrally rotatable with the armature core;
A plurality of power supply brushes pressed against the segments;
A direct current motor comprising:
Each of the teeth has a pair of branch teeth portions that are bifurcated at the tip portion so as to be separated in the circumferential direction,
The plurality of armature coils includes a plurality of concentrated winding inner layer coils wound around the base end portion of each tooth by concentrated winding and arranged in the circumferential direction without overlapping each other in the radial direction, and the concentrated winding inner layer coil And a plurality of distributed winding outer layer coils wound around the two branch tooth portions adjacent to each other on the outer peripheral side by the distributed winding and arranged in the circumferential direction without overlapping each other in the radial direction, The center in the circumferential direction of each concentrated winding inner layer coil and the center in the circumferential direction of each distributed winding outer layer coil are shifted in the circumferential direction,
The commutator includes the number of segments twice as many as the teeth and the same number as the branch teeth .
Of the plurality of segments (n is an even number of 2 or more), one end of the concentrated winding inner layer coil and one end of the distributed winding outer layer coil are connected one by one, and the remaining segments One end of the two concentrated winding inner layer coils is connected to one half of the segments, and one end of the two distributed winding outer layer coils is connected to the other half of the segments. DC motor characterized by The direct current motor according to claim 1,
P poles (P is an even number) are provided,
(360 / (P / 2)) The concentrated winding inner layer coil is connected to two of the plurality of segments via a short-circuit wire that short-circuits the (P / 2) segments located at an interval of °. And one end of the distributed outer layer coil are connected one by one, and two of the concentrated winding inner layer coils are connected one by one to the half of the remaining segments, and the other half A DC motor, wherein one end of each of the two distributed outer layer coils is connected to the segment. The DC motor according to claim 1 or 2,
The commutator includes the segments by an integer multiple of the number of the magnetic poles,
The armature core includes an inner slot through which the concentrated winding inner layer coil is inserted between the adjacent teeth, and an outer side through which the distributed winding outer layer coil is inserted between the branch tooth portions forming a pair of the teeth. The same number of slots as the inner slots, the sum of the inner slots and the outer slots is the same as the number of segments;
The feeding brush for the anode and the feeding brush for the cathode are arranged so as to be shifted in the opposite directions along the circumferential direction from a normal position on the magnetic pole center line passing through the circumferential center of the magnetic pole. The direct current motor is characterized in that the rectification by the power supply and the rectification by the power supply brush of the cathode are alternately performed. In the DC motor according to claim 3,
A high-resistance brush that is adjacent to the sliding contact portion that is in sliding contact with the segment of each power supply brush and that is shifted from the normal position of the adjacent power supply brush in a direction opposite to the direction in which the adjacent power supply brush is shifted. A direct current motor provided with