DC rotary electric machine

Abstract

To provide a DC rotary electric machine capable of suppressing a decrease in a bending amount of a power-supply lead wire so as to maintain contact between a brush and a rectifier when the brush is scraped and moved due to friction with the rectifier.SOLUTION: A DC rotary electric machine 100 includes a stator 2, a rotor 3, a brush 5, a power-supply lead wire 9 which has one end connected to the brush 5 and supplies power from the outside to the brush 5, and a terminal part 8 to which the other end of the power-supply lead wire 9 is connected and power from the outside is supplied. The power-supply lead wire 9 includes a sneak portion 94 which sneaks from a terminal junction portion 91 at which the power-supply lead wire 9 and the terminal part 8 are joined to the side opposite to the brush 5 and extends toward a brush junction portion 92 at which the other end of the power-supply lead wire 9 and the brush 5 are joined.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a DC rotating electric machine. [Background technology]

[0002] BACKGROUND ART DC rotating electric machines are known in the art (see, for example, Patent Document 1).

[0003] The above-mentioned Patent Document 1 discloses a DC motor (DC rotating electric machine) equipped with a commutator and brushes. This DC motor includes a magnet (stator), a rotor, a positive electrode plate, a negative electrode plate, and multiple lead wires.

[0004] The positive and negative plates of the above-mentioned Patent Document 1 are each connected to an external battery. A lead wire connects the positive plate to the brush. Another lead wire connects the negative plate to the brush. The lead wire is an electric wire called a pigtail and is flexible. The commutator and the brush are in sliding contact. Even if the brush is worn down due to friction with the commutator, the brush is biased by a coil spring, so its connection with the commutator is maintained. This allows power to be supplied to the rotor from the external battery.

[0005] The lead wires in Patent Document 1 extend linearly from the positive electrode plate (negative electrode plate) to the brushes, and are joined to the positive electrode plate (negative electrode plate) and the brushes by welding. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent Publication No. 2021-118554 Summary of the Invention [Problem to be solved by the invention]

[0007] However, in the DC motor of Patent Document 1, when the lead wires and the positive electrode plate (negative electrode plate) are welded together, the joint between the lead wires and the positive electrode plate (negative electrode plate) is heated, resulting in heat transfer to the lead wires. Here, the length of the lead wires is relatively short because they extend linearly from the positive electrode plate (negative electrode plate) to the brushes. For these reasons, in the DC motor of Patent Document 1, the lead wires harden due to the heat generated during welding, reducing the amount of deflection of the lead wires. In this case, in the DC motor of Patent Document 1, when the brushes are worn down and moved due to friction with the commutator, the amount of deflection of the lead wires decreases, hindering the movement of the brushes and making it impossible to maintain contact between the brushes and the commutator. Therefore, it has been desirable to suppress the reduction in the amount of deflection of the lead wires (power supply lead wires) and maintain contact between the brushes and the commutator when the brushes are worn down and moved due to friction with the commutator.

[0008] The present invention has been made to solve the above-mentioned problems, and one object of the present invention is to provide a DC rotating electric machine that can suppress a decrease in the amount of flexure of the power supply lead wires and maintain contact between the brushes and the commutator when the brushes are worn down and moved due to friction with the commutator. [Means for solving the problem]

[0009] In order to achieve the above object, one aspect of the present invention provides a DC rotating electric machine comprising: a stator; a rotor having a commutator and radially opposed to the stator; brushes arranged to contact the commutator; power supply leads having one end connected to the brushes and supplying external power to the brushes; and terminal portions to which the other end of the power supply leads is connected and to which external power is supplied, the power supply leads including a wraparound portion that wraps around from the terminal joint portion joining the power supply lead to the opposite side of the brushes, and extends towards the brush joint portion joining the other end of the power supply lead to the brushes.

[0010] In one aspect of the present invention, in a DC rotating electric machine, the power supply lead has a wraparound portion that wraps around from the terminal joint where the power supply lead and the terminal are joined to the opposite side of the brush and extends toward the brush joint where the other end of the power supply lead and the brush are joined. This allows the power supply lead to be longer by the length of the wraparound portion, thereby increasing the heat transfer distance when the power supply lead and the terminal are heated and joined. This prevents the portion of the power supply lead between the terminal joint and the brush joint from becoming too hot due to the heat generated when heating the power supply lead and the terminal, and thus prevents hardening of the portion of the power supply lead between the terminal joint and the brush joint. As a result, when the brush is worn away by friction with the commutator and moves due to heating of the power supply lead and the terminal, the amount of deflection of the power supply lead is prevented from decreasing, and contact between the brush and the commutator is maintained when the brush is worn away by friction with the commutator and moves. Furthermore, the wraparound portion ensures the length of the power supply lead, and the heat transfer distance of the power supply lead can be increased while preventing the distance from the terminal to the brush from increasing.

[0011] In the DC rotating electric machine according to the above aspect, preferably, when viewed from one axial side of the rotation axis of the rotor, the wraparound portion extends radially outward from the terminal joint portion, and then wraps around the side of the terminal portion opposite the terminal joint portion and extends radially inward.

[0012] By configuring it in this manner, the wraparound portion can be prevented from protruding in the axial direction, so even if the amount of deflection of the power supply lead wire increases by the length of the wraparound portion, interference with other components adjacent in the axial direction can be suppressed.

[0013] In this case, preferably, the motor further comprises a metal case that houses the stator and the rotor therein, and a first insulating partition wall provided between the inner circumferential surface of the case and the wraparound portion.

[0014] When the power supply lead vibrates, the amount of movement of the power supply lead due to vibration increases by the amount of bending of the power supply lead due to the length of the wraparound portion. Therefore, by providing the first insulating partition wall, contact between the case and the power supply lead can be effectively suppressed even when the amount of movement of the power supply lead due to vibration increases.

[0015] In the aforementioned DC rotating electric machine according to the first aspect, the power supply lead preferably further includes a pair of second insulating partition walls provided adjacent to each other in the circumferential direction of the rotation axis of the rotor.

[0016] With this configuration, when the power supply lead wires vibrate, even if the amount of movement of the power supply lead wires due to vibration increases by the amount of bending of the power supply lead wires due to the length of the wraparound portion, the second insulating partition can effectively prevent the pair of power supply lead wires from coming into contact with each other.

[0017] In the DC rotating electric machine according to the above aspect, the following configuration is also possible.

[0018] (Additional note 1) In the DC rotating electric machine including the first insulating partition wall, the first insulating partition wall includes a groove portion provided at a position radially opposite the terminal joint portion.

[0019] With this configuration, when the power supply lead wire and the terminal portion are heated and joined, the power supply lead wire can be inserted into the groove portion and extended, and then the power supply lead wire and the terminal portion can be heated and joined, making it easy to join the power supply lead wire and the terminal portion.

[0020] (Additional note 2) The DC rotating electric machine having the above-mentioned first insulating partition further includes a capacitor having a terminal connection lead wire connected to the terminal portion and a grounding lead wire grounded to the case, and the terminal connection lead wire is arranged axially outside the wraparound portion to restrict axial movement of the wraparound portion.

[0021] With this configuration, even if the amount of axial movement of the power supply lead wire due to vibration increases as the length of the wraparound portion increases when the power supply lead wire vibrates, the capacitor terminal connection lead wire can restrict the axial movement of the power supply lead wire due to vibration, thereby suppressing interference between the power supply lead wire and other components adjacent to it in the axial direction.

[0022] (Additional note 3) In a DC rotating electric machine in which the wraparound portion extends radially outward from the terminal joint portion, then wraps around the opposite side of the terminal portion from the terminal joint portion and extends radially inward, the power supply lead wire further includes a flexible U-shaped bending portion that is provided between the wraparound portion and the brush joint portion and is recessed toward the commutator side when viewed from one side in the axial direction.

[0023] By configuring it in this manner, it is possible to prevent the hardening of the flexible portion located between the wraparound portion and the brush joint portion due to heating the power supply lead wire and the terminal portion, thereby preventing a decrease in the amount of deflection of the lead wire at the flexible portion.

[0024] (Additional note 4) The DC rotating electric machine having the above-mentioned second insulating partition preferably further comprises a case that houses the stator and rotor inside, a first insulating partition that is provided between the inner surface of the case and the wraparound portion and that insulates the case from the power supply lead wire, and a resin holder that houses the brush and the power supply lead wire, and the first insulating partition and the second insulating partition are resin parts that are integrally formed with the resin holder.

[0025] With this configuration, the first insulating partition wall and the second insulating partition wall can be formed simply by adding recesses corresponding to the first insulating partition wall and the second insulating partition wall to the mold that forms the holder, making it possible to easily form the first insulating partition wall and the second insulating partition wall. [Effects of the Invention]

[0026] According to the present invention, as described above, it is possible to suppress a reduction in the amount of flexure of the power supply lead wire, and to maintain contact between the brush and the commutator when the brush is scraped and moved due to friction with the commutator. [Brief explanation of the drawings]

[0027] [Figure 1] 1 is a perspective view of a DC motor according to an embodiment; [Figure 2] 1 is a perspective view showing a DC motor according to an embodiment with a case removed; [Figure 3] FIG. 10 is a bottom view of the holder of the DC motor according to the embodiment, viewed from the Ax2 direction side. [Figure 4] 1 is a perspective view of a brush of a DC motor according to an embodiment, viewed from the D1 direction side. FIG. [Figure 5] FIG. 4 is a partial enlarged view of the Zm portion of FIG. 3. DETAILED DESCRIPTION OF THE INVENTION

[0028] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments of the present invention will be described with reference to the accompanying drawings.

[0029] The configuration of a DC motor 100 according to an embodiment will be described with reference to Figures 1 to 5. The DC motor 100 is an example of the "DC rotating electric machine" in the claims.

[0030] As shown in Figures 1 and 2, a DC motor 100 is used as a drive source for various parts of a vehicle, driven by power supplied from an external battery. The DC motor 100 includes a case 1, a plurality of permanent magnets 2, a rotor 3, a holder 4, brushes 5 (see Figure 3), a commutator 6 (see Figure 3), a biasing member 7, a terminal section 8 (see Figure 3), power supply leads 9 (see Figure 3), and a capacitor 10 (see Figure 3). The plurality of permanent magnets 2 are an example of a "stator" in the claims. The terminal section 8 is an example of a "terminal section" in the claims.

[0031] Here, the axial direction, which is the direction in which the central axis C of rotation of the rotor 3 extends, is the Ax direction, one side of the Ax direction is the Ax1 direction, and the other side of the Ax direction is the Ax2 direction. The circumferential direction around the central axis C of rotation of the rotor 3 is the R direction, one side of the R direction is the R1 direction, and the other side of the R direction is the R2 direction. The radial direction perpendicular to the direction in which the central axis C of rotation of the rotor 3 extends is the D direction, the outer side of the D direction is the D1 direction, and the inner side of the D direction is the D2 direction. The Ax2 direction is an example of "one side in the axial direction" and "outer side in the axial direction" in the claims.

[0032] The case 1 is a cylindrical, metallic motor case. The case 1 houses a plurality of permanent magnets 2, a rotor 3, and a holder 4. The holder 4 is fitted inside the case 1.

[0033] As shown in Fig. 2, each of the multiple permanent magnets 2 is attached to the inner surface of the motor case 21. Each of the multiple permanent magnets 2 faces the rotor 3 in the direction D1. The rotor 3 includes a rotor core 31 and a coil 32. The rotor core 31 is fixed to the rotating shaft 201. The rotor core 31 is covered with an insulator (not shown). The coil 32 is wound around the rotor core 31.

[0034] (holder) As shown in Fig. 3, holder 4 is a holding member made of resin. Holder 4 includes a wire insertion portion 41 (see Fig. 2), a brush holder 42, a lead wire accommodating space portion 43, a biasing member mounting portion 44, a first insulating partition wall 45, a second insulating partition wall 46, and a circular portion 47. Each of wire insertion portion 41, brush holder 42, biasing member mounting portion 44, first insulating partition wall 45, and second insulating partition wall 46 is a resin portion that is integrally formed with circular portion 47 of holder 4 made of resin.

[0035] Wire insertion portion 41 is a portion having an internal space into which wires 301 (see FIG. 2) and 302 (see FIG. 2) for electrically connecting to an external battery are inserted. Wire insertion portion 41 protrudes from circular portion 47 in the Ax1 direction.

[0036] The brush holder 42 is a portion in which the brush 5 is housed so as to be movable in the D direction. When viewed from the Ax2 side, a pair of brush holders 42 are provided symmetrically with respect to a line S extending along the D direction. Each of the pair of brush holders 42 protrudes from the circular portion 47 in the Ax2 direction. Each of the pair of brush holders 42 extends along the D direction. Each of the pair of brush holders 42 has a through hole that passes through along the D direction. The brush 5 is housed inside this through hole so as to be movable in the D direction.

[0037] The lead wire accommodating space 43 is an internal space of the holder 4 that accommodates the power supply lead wire 9. A pair of the lead wire accommodating spaces 43 are provided symmetrically with respect to a line S extending along the D direction when viewed from the Ax2 direction side. Each of the pair of lead wire accommodating spaces 43 is provided on the Ax2 direction side of the circular portion 47. Each of the pair of lead wire accommodating spaces 43 is a space between the brush holder 42 and the second insulating partition wall 46 in the R direction, and is also a space between the first insulating partition wall 45 and the inner circumferential edge of the holder 4 on the D2 direction side in the D direction.

[0038] The biasing member attachment portion 44 is a boss portion to which the biasing member 7 is attached. The biasing member attachment portion 44 protrudes from the circular portion 47 in the Ax2 direction.

[0039] <First insulating partition> As shown in FIG. 3 , the first insulating partition wall 45 is a portion that insulates the case 1 from the power supply lead wire 9. When viewed from the Ax2 side, a pair of first insulating partition walls 45 are provided symmetrically with respect to a line S extending along the D direction. Each of the pair of first insulating partition walls 45 protrudes in the Ax2 direction from the circular portion 47 of the holder 4. When viewed from the Ax2 side, each of the pair of first insulating partition walls 45 has an arc shape extending along the R direction. One of the pair of first insulating partition walls 45 extends in the R1 direction from an end of the second insulating partition wall 46 on the D1 side. The other of the pair of first insulating partition walls 45 extends in the R2 direction from an end of the second insulating partition wall 46 on the D1 side. Each of the pair of first insulating partition walls 45 is provided in the D direction between the inner circumferential surface 1a of the case 1 and a wraparound portion 94 (described later) of the power supply lead wire 9.

[0040] Each of the pair of first insulating partition walls 45 includes a groove 45a provided at a position facing a terminal joint portion 91, which is a joint portion of the power supply lead wire 9 with a terminal portion 8 described later, in the D1 direction. As shown in FIG. 4, the groove 45a is recessed in the Ax1 direction from the end of the first insulating partition wall 45 on the Ax2 side. The depth De of the groove 45a is set to match the position of the terminal portion 8 in the Ax direction. As a result, the power supply lead wire 9 (shown by dotted lines in FIGS. 3 and 4) is inserted into the groove 45a while extending along the D1 direction. Furthermore, the power supply lead wire 9 inserted into the groove 45a is positioned at the bottom of the groove 45a, thereby being aligned with the position of the terminal portion 8 in the Ax direction. In this way, the groove 45a is a structure that facilitates the joining operation of the power supply lead wire 9 and the terminal portion 8.

[0041] <Second insulating partition> 3, the second insulating partition wall 46 is a portion that insulates the pair of power supply lead wires 9 from each other. The second insulating partition wall 46 protrudes in the Ax2 direction from the circular portion 47 of the holder 4. When viewed from the Ax2 side, the second insulating partition wall 46 has a linear shape that extends along the D direction. The second insulating partition wall 46 is provided between the pair of power supply lead wires 9 in the R direction.

[0042] When viewed from the Ax2 direction side, the circular portion 47 has a circular shape that conforms to the inner circumferential surface 1a of the case 1. The circular portion 47 is a portion that is fitted into the inner circumferential surface 1a of the case 1.

[0043] (Brush, commutator, biasing member and terminal part) The brush 5 is configured to supply power to the commutator 6. The end of the brush 5 on the D2 direction side is in contact with the commutator 6 from the outer periphery. Here, power supplied from the wiring 301 and the wiring 302 is supplied from the brush 5 to the commutator 6 via each of a pair of power supply lead wires 9. The commutator 6 is fixed to the rotating shaft 201. The commutator 6 rotates integrally with the rotating shaft 201. The commutator 6 is in slidable contact with the brush 5. The biasing member 7 biases the brush 5 toward the commutator 6 (in the D2 direction). The biasing member 7 is a torsion spring. One end of the biasing member 7 is fixed to the holder 4. The other end 7a of the biasing member 7 is maintained in contact with the brush 5 (see FIG. 4). Power is supplied to the terminal portion 8 from an external source. When viewed from the Ax2 direction, a pair of terminal portions 8 are provided symmetrically with respect to a straight line S extending along the D direction. A terminal joint portion 91 of the power supply lead wire 9 is connected to each of the pair of terminal portions 8. A capacitor 10 is connected to each of the pair of terminal portions 8. A wiring 301 (see FIG. 2) and a wiring 302 (see FIG. 2) are also connected to the pair of terminal portions 8, respectively. The terminal joint portion 91 of the power supply lead wire 9 is an example of the "other end of the power supply lead wire" in the claims.

[0044] (power supply lead wire) As shown in FIG. 5, the power supply lead wire 9 is connected to the brush 5 at a brush joint 92 (see FIG. 4), and is a component that supplies external power to the brush 5. The power supply lead wire 9 is a so-called pigtail. The power supply lead wires 9 are arranged in a pair adjacent to each other in the R direction. Since the pair of power supply lead wires 9 have the same structure, only the structure of the power supply lead wire 9 on the R1 side will be described. The brush joint 92 of the power supply lead wire 9 is an example of "one end of the power supply lead wire" in the claims.

[0045] The power supply lead wire 9 is configured to bend so that the brush 5 can move by an amount corresponding to wear of the brush 5 due to sliding against the commutator 6. Specifically, the power supply lead wire 9 includes a terminal joint portion 91, a brush joint portion 92 (see FIG. 4), a bending portion 93, and a wraparound portion 94.

[0046] The terminal joint 91 is a portion where one end of the power supply lead wire 9 is joined to the terminal portion 8. The terminal joint 91 is formed by welding the power supply lead wire 9 to the terminal portion 8. The terminal joint 91 is formed on the surface of the terminal portion 8 on the R1 direction side.

[0047] 4, the brush joint 92 is a portion where the other end of the power supply lead wire 9 and the brush 5 are joined. The brush joint 92 is formed by welding the power supply lead wire 9 and the brush 5. The brush joint 92 is formed on the surface of the brush 5 on the R2 direction side.

[0048] As shown in FIG. 5 , the flexible portion 93 is a flexible U-shaped portion recessed toward the commutator 6 when viewed from the Ax2 direction. The flexible portion 93 increases the length of the power supply lead wire 9 to accommodate the maximum movement distance of the brush 5 due to wear of the brush 5. The power supply lead wire 9 including the flexible portion 93 is formed from a flexible material and structure. As a result, the flexible portion 93 bends in accordance with the movement of the brush 5. The flexible portion 93 is provided between the wraparound portion 94 and the brush joint portion 92.

[0049] <Wraparound section> In this embodiment, the wraparound portion 94 wraps around from the terminal joint portion 91 to the opposite side of the brush 5 and extends toward the brush joint portion 92. The wraparound portion 94 is provided to increase the heat transfer distance from the terminal joint portion 91 to the flexible portion 93 when the terminal joint portion 91 is welded. Here, due to the wraparound portion 94 and the flexible portion 93, the length from the terminal joint portion 91 of the power supply lead wire 9 to the brush joint portion 92 is longer than the shortest distance Dmin.

[0050] When viewed from the Ax2 direction, the wraparound portion 94 extends from the terminal joint portion 91 toward the D1 direction, then wraps around the side of the terminal portion 8 opposite the terminal joint portion 91, and extends toward the D2 direction. That is, the wraparound portion 94 extends from the terminal joint portion 91 in the D1 direction, and then extends in the R2 direction along the surface of the terminal portion 8 on the D1 direction side. The wraparound portion 94 extends in the R2 direction, and then extends toward the D2 direction at an angle relative to the D2 direction. Thus, the wraparound portion 94 has a U-shape when viewed from the Ax2 direction.

[0051] The power supply lead wire 9 having the wraparound portion 94 is accommodated in the lead wire accommodating space 43 in the Ax direction. The power supply lead wire 9 having the wraparound portion 94 is accommodated in the lead wire accommodating space 43 in the R direction.

[0052] (Movement of power supply lead wire due to brush wear) As the brush 5 wears, the brush 5 and the brush joint 92 of the power supply lead 9 move in the direction D2 within the brush holder 42 due to the biasing force of the biasing member 7. In accordance with this movement, the power supply lead 9 is fixed in position at the brush joint 92, so it moves while bending the bending portion 93. This maintains the abutting state between the brush 5 and the commutator 6.

[0053] (Capacitor) As shown in FIG. 5, the capacitor 10 is provided to remove electrical noise from the DC motor 100. The capacitor 10 has a terminal connection lead wire 10a and a grounding lead wire 10b. The terminal connection lead wire 10a is connected to the terminal unit 8. The terminal connection lead wire 10a is arranged on the Ax2 side of the wraparound portion 94 to restrict axial movement of the wraparound portion 94. The terminal connection lead wire 10a passes along the R1 direction on the Ax2 side of the wraparound portion 94, and is then connected to the surface of the terminal unit 8 on the R1 side. The grounding lead wire 10b is grounded to the case 1.

[0054] (Effects of this embodiment) In this embodiment, the following effects can be obtained.

[0055] In this embodiment, as described above, the power supply lead wire 9 includes a wraparound portion 94 that wraps around from the terminal joint 91, which joins the power supply lead wire 9 and the terminal portion 8, to the side opposite the brush 5, and extends toward the brush joint 92, which joins the other end of the power supply lead wire 9 and the brush 5. This allows the power supply lead wire 9 to be longer by the length of the wraparound portion 94, thereby increasing the heat transfer distance when the power supply lead wire 9 and the terminal portion 8 are heated and joined. This prevents the portion (flexed portion 93) of the power supply lead wire 9 between the terminal joint 91 and the brush joint 92 from becoming too hot due to the heat generated by heating the power supply lead wire 9 and the terminal portion 8, and thus prevents the portion of the power supply lead wire 9 between the terminal joint 91 and the brush joint 92 from hardening. As a result, it is possible to suppress a decrease in the amount of bending of the power supply lead wire 9 when the brush 5 is scraped and moved due to friction with the commutator 6, which is caused by heating the power supply lead wire 9 and the terminal portion 8, and therefore it is possible to suppress a decrease in the amount of bending of the power supply lead wire 9 and maintain contact between the brush 5 and the commutator 6 when the brush 5 is scraped and moved due to friction with the commutator 6. Furthermore, since the wraparound portion 94 ensures the length of the power supply lead wire 9, it is possible to increase the heat transfer distance of the power supply lead wire 9 while suppressing an increase in the distance from the terminal portion 8 to the brush 5.

[0056] Furthermore, in this embodiment, as described above, the wraparound portion 94 extends from the terminal joint portion 91 toward the D1 direction when viewed from the Ax2 direction side of the rotation axis of the rotor 3, and then wraps around the side of the terminal portion 8 opposite the terminal joint portion 91 side and extends toward the D2 direction. This prevents the wraparound portion 94 from protruding in the Ax direction, and therefore, even if the amount of flexure of the power supply lead wire 9 increases by the length of the wraparound portion 94, interference with other components adjacent in the Ax direction can be suppressed.

[0057] Furthermore, in this embodiment, as described above, the DC motor 100 includes the metal case 1 that houses the permanent magnet 2 and the rotor 3, and the first insulating partition wall 45 that is provided between the inner circumferential surface 1a of the case 1 and the wraparound portion 94. When the power supply lead wire 9 vibrates, the amount of movement of the power supply lead wire 9 due to the vibration increases by the amount of bending of the power supply lead wire 9 that increases due to the length of the wraparound portion 94. Therefore, by providing the first insulating partition wall 45, it is possible to effectively prevent contact between the case 1 and the power supply lead wire 9 even when the amount of movement of the power supply lead wire 9 due to vibration increases.

[0058] Furthermore, in this embodiment, as described above, a pair of power supply leads 9 are provided adjacent to each other in the direction R of the rotation axis of the rotor 3. The DC motor 100 includes a second insulating partition wall 46 provided between the pair of power supply leads 9. As a result, when the power supply leads 9 vibrate, even if the amount of movement of the power supply leads 9 due to vibration increases by the amount of bending of the power supply leads 9 due to the length of the wraparound portion 94, the second insulating partition wall 46 can effectively prevent the pair of power supply leads 9 from coming into contact with each other.

[0059] [Variations] The above-described embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present invention is defined by the claims rather than the description of the above-described embodiments, and further includes all modifications (variations) within the meaning and scope of the claims.

[0060] For example, in the above embodiment, when viewed from the Ax2 direction (one side in the axial direction of the rotor's rotation axis), the wraparound portion 94 extends from the terminal joint portion 91 in the D1 direction (radially outward), then wraps around the side of the terminal portion 8 (terminal portion) opposite the terminal joint portion 91 side and extends in the D2 direction (radially inward), but the present invention is not limited to this. In the present invention, the wraparound portion may extend axially from the terminal joint portion and then extend radially inward on the side of the terminal portion opposite the terminal joint portion side.

[0061] In the above embodiment, the holder 4 includes the first insulating partition wall 45 and the second insulating partition wall 46, but the present invention is not limited to this. In the present invention, the holder does not necessarily include the first insulating partition wall and the second insulating partition wall, or may include either the first insulating partition wall or the second insulating partition wall.

[0062] In the above embodiment, the terminal joint 91 is formed by welding the power supply lead wire 9 and the terminal portion 8 (terminal portion), but the present invention is not limited to this. In the present invention, the terminal joint may be formed by welding the power supply lead wire and the terminal portion by thermal caulking, or may be formed by a method of joining other heated metal materials together.

[0063] In the above embodiment, the DC motor 100 (DC rotating electric machine) is driven by power supplied from an external battery and is used as a drive source for various parts of a vehicle, but the present invention is not limited to this. In the present invention, the DC rotating electric machine may be used as a drive source for various parts other than the vehicle.

[0064] In the above embodiment, the DC motor 100 is used as the "DC rotating electric machine" in the claims, but the present invention is not limited to this. In the present invention, the "DC rotating electric machine" in the claims may be a generator or the like. [Explanation of symbols]

[0065] 1 case, 1a inner peripheral surface, 2 permanent magnet (stator), 3 rotor, 5 brush, 6 commutator, 8 terminal portion (terminal portion), 9 power supply lead wire, 21 motor case (case), 45 first insulating partition wall, 46 second insulating partition wall, 91 terminal joint portion, 92 brush joint portion, 94 wraparound portion, 100 DC motor (DC rotating electric machine), C rotation central axis

Claims

1. a stator; a rotor having a commutator and facing the stator in a radial direction; a brush provided in contact with the commutator; a power supply lead wire connected to the brush at one end and configured to supply power from an external source to the brush; a terminal portion to which the other end of the power supply lead wire is connected and to which power is supplied from an external source, the power supply lead wire includes a wraparound portion that wraps around from a terminal joint portion that joins the power supply lead wire and the terminal portion to a side opposite the brush, and extends toward a brush joint portion that joins the other end of the power supply lead wire and the brush.

2. 2. The DC rotating electric machine according to claim 1, wherein, when viewed from one axial side of the rotation axis of the rotor, the wraparound portion extends radially outward from the terminal joint portion, and then wraps around the opposite side of the terminal portion from the terminal joint portion and extends radially inward.

3. a metal case that houses the stator and the rotor; The DC rotating electric machine according to claim 2 , further comprising a first insulating partition wall provided between an inner circumferential surface of the case and the wraparound portion.

4. a pair of the power supply lead wires are provided adjacent to each other in a circumferential direction of the rotation axis of the rotor, The DC rotating electric machine according to claim 1 , further comprising a second insulating partition wall provided between the pair of power supply leads.

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