Motor

Abstract

According to the present invention, a coil is continuously wound in a single pass around each of a series of teeth, and connected to each segment.

Claims

1. A motor, comprising: a yoke having four magnetic poles; an armature core, having a rotary shaft rotatably provided radially inside the yoke, six teeth attached to the rotary shaft and extending radially outward, and six slots formed between each of the teeth adjacent in a circumferential direction; a coil wound around each of the teeth; a commutator provided adjacent to the armature core on the rotary shaft, on which twelve segments are disposed in the circumferential direction; and a plurality of brushes supplying power to the coil via each of the segments, wherein when the teeth are sequentially numbered from 1 to 6 in the circumferential direction and the segments are sequentially numbered from 1 to 12 in the circumferential direction, a winding start terminal of the coil is connected to the first segment, and the coil is pulled around in one direction in a rotational direction of the rotary shaft from the first segment and wound around the fifth tooth in a forward direction, pulled around in the one direction from the fifth tooth and wound around the second tooth in the forward direction, pulled around in the one direction from the second tooth and connected to the twelfth segment, pulled around in the one direction from the twelfth segment and connected to the sixth segment, pulled around in the one direction from the sixth segment and wound around the sixth tooth in a reverse direction opposite the forward direction, pulled around in the one direction from the sixth tooth and wound around the third tooth in the reverse direction, pulled around in the one direction from the third tooth and connected to the eleventh segment, pulled around in the one direction from the eleventh segment and connected to the fifth segment, pulled around in the one direction from the fifth segment and wound around the first tooth in the forward direction, pulled around in the one direction from the first tooth and wound around the fourth tooth in the forward direction, pulled around in the one direction from the fourth tooth and connected to the fourth segment, pulled around in the one direction from the fourth segment and connected to the tenth segment, pulled around in the one direction from the tenth segment and wound around the second tooth in the reverse direction, pulled around in the one direction from the second tooth and wound around the fifth tooth in the reverse direction, pulled around in the one direction from the fifth tooth and connected to the third segment, pulled around in the one direction from the third segment and connected to the ninth segment, pulled around in the one direction from the ninth segment and wound around the third tooth in the forward direction, pulled around in the one direction from the third tooth and wound around the sixth tooth in the forward direction, pulled around in the one direction from the sixth tooth and connected to the eighth segment, pulled around in the one direction from the eighth segment and connected to the second segment, pulled around in the one direction from the second segment and wound around the fourth tooth in the reverse direction, pulled around in the one direction from the fourth tooth and wound around the first tooth in the reverse direction, pulled around in the one direction from the first tooth and connected to the seventh segment, and pulled around in the one direction from the seventh segment and connected to the first segment.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a cross-sectional view of a brushed motor along an axial direction according to an embodiment of the present invention.

(2) FIG. 2 is an expanded view of permanent magnets, teeth, segments, and a coil according to an embodiment of the present invention.

(3) FIG. 3 is an explanatory diagram showing an electric circuit of a coil according to an embodiment of the present invention.

(4) FIG. 4 is an explanatory diagram showing an electric circuit of a conventional coil.

DESCRIPTION OF THE EMBODIMENTS

(5) Next, an embodiment of the present invention is described based on the drawings.

(6) (Brushed Motor)

(7) FIG. 1 is a cross-sectional view of a brushed motor 1 along an axial direction.

(8) The brushed motor 1 is, for example, used as a driving source for electrical equipment mounted on a vehicle.

(9) As shown in FIG. 1, the brushed motor 1 includes an armature 3 rotatably provided in a substantially bottomed cylindrical yoke 2, and an opening part 2c of the yoke 2 is closed with an end bracket 17.

(10) Four permanent magnets 4 are fixed to an inner peripheral surface of the yoke 2 in a circumferential direction. That is, there are four magnetic poles.

(11) The armature 3 includes an armature core 6 fixed to a rotary shaft 5, a coil 7 wound around the armature core 6, and a commutator 13 disposed at one end of the armature core 6. The armature core 6 is formed by, for example, laminating a plurality of ring-shaped metal plates 8 in the axial direction. However, the armature core 6 may be formed by compression molding soft magnetic powder.

(12) On an outer peripheral part of the metal plates 8, six T-shaped teeth 50 are formed radially at equal intervals along the circumferential direction when viewed from the axial direction Since the plurality of metal plates 8 are externally fitted to the rotary shaft 5, dovetail groove-like slots 51 are formed between adjacent teeth 50 on an outer periphery of the armature core 6. The slots 51 extend along the axial direction, and there are six slots 51 formed at equal intervals along the circumferential direction. Through these slots 51, the coil 7 is wound around the teeth 50 by a concentrated winding method (the details will be described later).

(13) The commutator 13 is externally fitted and fixed to one end of the rotary shaft 5. Twelve segments 14 formed of a conductive material are attached to an outer peripheral surface of the commutator 13. In this way, the brushed motor 1 of the present embodiment is a so-called four-pole six-slot twelve-segment (double segment) motor, having four permanent magnets 4 (the number of magnetic poles is four), six slots 51 (six teeth 50), and twelve segments 14.

(14) The segments 14 are formed of plate-shaped metal pieces that are long in the axial direction, and are fixed in parallel at equal intervals along the circumferential direction while being insulated from each other. At an end part of each segment 14 toward the armature core 6, a riser 15 bent in the form of being folded back to an outer diameter side is formed integrally with the segment 14. The coil 7 wound around the teeth 50 is wound around the riser 15 and fixed by, for example, fusing. Accordingly, the segments 14 and the corresponding coil 7 are electrically connected.

(15) In addition, the coil 7 is connected so that predetermined two of the segments 14, that is, two segments 14 having the same potential, are short-circuited (see FIG. 2; the details will be described later). The coil 7 that short-circuits the two segments 14 having the same potential functions as an equalizer (connection line) 52. These equalizers 52 are also wound around the riser 15 of the predetermined segments 14 and fixed by, for example, fusing.

(16) The other end of the rotary shaft 5 is rotatably supported by a bearing 12 in a boss formed protruding from a bottom part 2b of the yoke 2. The end bracket 17 is provided at an end of the yoke 2 toward the opening part 2c. A holder stay 20 is attached inside the end bracket 17. A pair of brush holders 21 at a 90° interval in the circumferential direction, for example, is formed on the holder stay 20. The brush holders 21 are respectively equipped with brushes 22 that are freely retractable while being energized via a spring 23.

(17) Each brush 22 is electrically connected to an external power supply via a pigtail 16. Each brush 22 is classified into a positive brush and a negative brush. Tip parts of these brushes 22 come into slide contact with the commutator 13 because they are energized by the spring 23, and external power is supplied to the commutator 13 via the brushes 22.

(18) (Coil Winding Method)

(19) Next, a method for winding the coil 7 is described based on FIG. 2.

(20) FIG. 2 is an expanded view of the permanent magnets 4 as well as the teeth 50, the segments 14, and the coil 7 (equalizers 52) of the armature 3, wherein gaps between the adjacent teeth 50 correspond to the slots 51.

(21) As shown in FIG. 2, the armature 3 has a three-phase (U-phase, V-phase, and W-phase) structure, and each tooth 50 is assigned as the U-phase, the V-phase, and the W-phase in this order along the circumferential direction. In the following description, the phases and numbers assigned to each tooth 50 are sequentially assigned, and each segment 14 is sequentially numbered in the circumferential direction and described. Although in FIG. 2, each segment 14 is numbered so that the first segment 14 is located in the vicinity of the tooth 50 numbered U1(1), the present invention is not limited thereto and the location of the first segment 14 can be set arbitrarily.

(22) The coil 7 is continuously pulled around each tooth 50 and each segment 14 in a single stroke. In addition, the coil 7 is always pulled around in one direction in a rotational direction of the armature 3 (rotary shaft 5). In FIG. 2, the coil 7 is pulled around to the right.

(23) That is, firstly, a winding start terminal 7a of the coil 7 is connected to the first segment 14. Subsequently, the coil 7 is wound around the tooth 50 numbered V2(5) in a forward direction (clockwise direction in FIG. 2) from the first segment 14 to form a second V-phase forward coil 72Va.

(24) Subsequently, the coil 7 is pulled out from the tooth 50 numbered V2(5), and the coil 7 is wound around the tooth 50 numbered V1(2) in the forward direction to form a first V-phase forward coil 71Va.

(25) Subsequently, the coil 7 is pulled out from the tooth 50 numbered V1(2), and the coil 7 is wound around the riser 15 of the twelfth segment 14.

(26) Subsequently, the coil 7 is wound around the riser 15 of the sixth segment 14 from the twelfth segment 14.

(27) Subsequently, the coil 7 is pulled out from the sixth segment 14, and the coil 7 is wound around the tooth 50 numbered W2(6) in a reverse direction (counterclockwise direction in FIG. 2) to form a second W-phase reverse coil 72Wb.

(28) Subsequently, the coil 7 is pulled out from the tooth 50 numbered W2(6), and the coil 7 is wound around the tooth 50 numbered W1(3) in the reverse direction to form a first W-phase reverse coil 71Wb.

(29) Subsequently, the coil 7 is pulled out from the tooth 50 numbered W1(3), and the coil 7 is wound around the riser 15 of the eleventh segment 14.

(30) Subsequently, the coil 7 is wound around the riser 15 of the fifth segment 14 from the eleventh segment 14.

(31) Subsequently, the coil 7 is pulled out from the fifth segment 14, and the coil 7 is wound around the tooth 50 numbered U1(1) in the forward direction to form a first U-phase forward coil 71Ua.

(32) Subsequently, the coil 7 is pulled out from the tooth 50 numbered U1(1), and the coil 7 is wound around the tooth 50 numbered U2(4) in the forward direction to form a second U-phase forward coil 72Ua.

(33) Subsequently, the coil 7 is pulled out from the tooth 50 numbered U2(4), and the coil 7 is wound around the riser 15 of the fourth segment 14.

(34) Subsequently, the coil 7 is wound around the riser 15 of the tenth segment 14 from the fourth segment 14.

(35) Subsequently, the coil 7 is pulled out from the tenth segment 14, and the coil 7 is wound around the tooth 50 numbered V1(2) in the reverse direction to form a first V-phase reverse coil 71Vb.

(36) Subsequently, the coil 7 is pulled out from the tooth 50 numbered V1(2), and the coil 7 is wound around the tooth 50 numbered V2(5) in the reverse direction to form a second V-phase reverse coil 72Vb.

(37) Subsequently, the coil 7 is pulled out from the tooth 50 numbered V2(5), and the coil 7 is wound around the riser 15 of the third segment 14.

(38) Subsequently, the coil 7 is wound around the riser 15 of the ninth segment 14 from the third segment 14.

(39) Subsequently, the coil 7 is pulled out from the ninth segment 14, and the coil 7 is wound around the tooth 50 numbered W1(3) in the forward direction to form a first W-phase forward coil 71Wa.

(40) Subsequently, the coil 7 is pulled out from the tooth 50 numbered W1(3), and the coil 7 is wound around the tooth 50 numbered W2(6) in the forward direction to form a second W-phase forward coil 72Wa.

(41) Subsequently, the coil 7 is pulled out from the tooth 50 numbered W2(6), and the coil 7 is wound around the riser 15 of the eighth segment 14.

(42) Subsequently, the coil 7 is wound around the riser 15 of the second segment 14 from the eighth segment 14.

(43) Subsequently, the coil 7 is pulled out from the second segment 14, and the coil 7 is wound around the tooth 50 numbered U2(4) in the reverse direction to form a second U-phase reverse coil 72Ub.

(44) Subsequently, the coil 7 is pulled out from the tooth 50 numbered U2(4), and the coil 7 is wound around the tooth 50 numbered U1(1) in the reverse direction to form a first U-phase reverse coil 71Ub.

(45) Subsequently, the coil 7 is pulled out from the tooth 50 numbered U1(1), and the coil 7 is wound around the riser 15 of the seventh segment 14.

(46) Subsequently, the coil 7 is pulled out from the seventh segment 14, and a winding end terminal 7b of the coil 7 is connected to the first segment 14. Accordingly, a winding operation of the coil 7 is completed.

(47) (About Electric Circuit of Coil)

(48) Next, an electric circuit of the coil 7 wound as described above is described based on FIG. 3.

(49) FIG. 3 is an explanatory diagram showing an electric circuit of the coil 7.

(50) As shown in FIG. 3, for example, in the case where the brush 22 is in slide contact with the first segment 14 and the fourth segment 14 respectively, a circuit to which the coil 7 is connected in series is formed between the first and fourth segments 14, and a circuit to which the coil 7 is connected in series is formed between the seventh and tenth segments 14. These two circuits are connected in parallel. Hence, for example, in the case where a current value supplied to the brush 22 is 4[i], currents supplied to each circuit each have a current value of 2[i] In addition, a current supplied to the equalizer 52 also has a current value of 2[i].

(51) In this way, in the above-described embodiment, while the brushed motor 1 can be reduced in size, the coil 7 wound around each tooth 50 can be connected to each segment 14. Hence, it can be prevented that the value of the current flowing through the coil 7 connecting the segments 14 having the same potential may increase.

(52) In addition, by a single flyer, the winding operation of the coil 7 can be performed continuously in a single stroke. Hence, a winding device can be simplified and the winding operation of the coil 7 can be facilitated.

(53) In addition, compared to the case where the coil 7 is wound by a double flyer, since the coil 7 is wound by a single flyer, the number of turns of the coil 7 can be reduced, and the amount of coating of the coil 7 can be reduced. As a result, it is possible to improve a space factor of the coil 7.

(54) The present invention is not limited to the above-described embodiment, and includes various modifications of the above-described embodiment without departing from the spirit of the present invention.

(55) For example, in the above-described embodiment, the case is described where the brushed motor 1 is used as the driving source for electrical equipment (for example, a power window) mounted on a vehicle. However, the present invention is not limited thereto, and the brushed motor 1 can be employed for driving various machines.

INDUSTRIAL APPLICABILITY

(56) According to the above motor, a motor can be provided that can be reduced in size and that is capable of reducing a value of a current flowing through a connection line, simplifying a winding device, improving a space factor of a coil, and facilitating a winding operation.