JP2008172943A - Dc motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a DC motor in which a manufacturing cost is reduced by allowing a brush holding plate to have versatility and the lifetime is prolonged by using the brush up to its usage limit. <P>SOLUTION: Brush holders 41-44 are independently from the brush holding plate 3, coupling portion engaged with each other to connect the brush holders 41-44 to the brush holding plate 3 are provided between the brush holders 41-44 and the brush holding plate 3, and the brush holders 41-44 are coupled to the holding plate 3 via the coupling portions. Slits 4c provided on the brush holders 41-44 to lead pigtails 61-64 from brushes 51-54 in the brush holders 41-44 and insert springs 7 for applying force to the brushes 51-54 into the brush holders 41-44 are each provided in a state where an end portion positioned on the side opposite to the commutator 2 is closed and the end portion of the end portion of the commutator 2 side is opened on the commutator side. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a DC motor including a rectifying mechanism having a brush and a commutator.

  For example, as shown in FIG. 11, a DC motor provided with a rectifying mechanism includes a commutator 2 attached to a rotor rotating shaft 1 and connected to a coil on the rotor side, and a hole 3 a that penetrates the commutator 2. A disc-shaped brush holding plate 3 ′ provided at the center portion and disposed on the outer side in the radial direction of the commutator 2, and on the surface side of the brush holding plate 3 ′ so as to extend in the radial direction of the commutator 2. A brush holder 4 ′ held and a brush 5 slidably held in the brush holder 4 ′ and brought into contact with the commutator 2 are provided. The brush holder 4 'is integrated with the brush holding plate 3'.

  As shown in FIGS. 12 and 13, the brush holder 4 'includes a pair of side wall portions 4a2' protruding from both ends in the width direction of the top plate 4a1 'and the top plate 4a1' to the same side (brush holding plate side). 4a2 'is formed in a duct shape and is provided integrally with the brush holding plate 3'. Both side walls 4a2 'and 4a2' of the brush holder 4 'are provided with slits 4c' and 4c 'extending along the radial direction of the commutator, and a pigtail 6 connected to the brush held in the brush holder is provided. It is led out of the brush holder through one slit 4c '. The brush 5 in the brush holder is urged toward the commutator 2 by a spring 7 held by the brush holding plate 3 'and having an end inserted into the other slit 4c'. The commutator 2, the brush holding plate 3 ′, and the brush 5 held on the brush holding plate via the brush holder 4 ′ constitute a rectifying mechanism. A rotor (not shown) having an armature coil is attached to the rotary shaft 1, and a stator having a field is disposed outside the rotor. A DC motor is constituted by the rotor and the stator and the rectifying mechanism.

In the conventional electric motor of this type, the brush holder 4 'is formed integrally with the brush holding plate 3'. Therefore, in order to allow the brush 5 to be inserted into the brush holder 4 ', Patent Document 2 discloses that. As shown, slits 4c 'and 4c' provided in the side wall portions 4a2 'and 4a2' of the brush holder 4 'open to the outer diameter side (opposite side of the commutator) of the brush holding plate 3'. It is provided in a closed state on the child 2 side. This type of electric motor is disclosed in Patent Document 1 and Patent Document 2, for example.
JP-A-9-308203 Japanese Patent Laid-Open No. 2002-136061

  In the conventional DC motor, the brush holding plate 3 ′ and the brush holder 4 ′ are integrally formed. However, the opening direction of the hollow portion of the brush holder 4 ′ and the opening direction of the slit 4 c ′ are the same. Since it is different from the opening direction of the hole at the center of 3 ', the brush holding plate 3' and the brush holder cannot be injection-molded at a time. In order to integrate the brush holder 4 'with the brush holding plate, when the brush holding plate is formed, a mold for forming the brush holding plate using a slide jig for the brush holder 4' formed in a separate process. It was necessary to insert in. For this reason, it is necessary to use expensive molds and injection molding machines, and it is inevitable that the manufacturing cost becomes high.

  When the size and shape of the brush holder 4 'are changed, it is necessary to change the entire mold for molding the brush holding plate. Therefore, the brush holding plate is shared with the brush holder having various sizes and shapes. I couldn't. Therefore, the brush holding plate cannot be provided with versatility, and every time the shape of the brush holder is changed, the entire brush holder and the brush holding plate need to be reshaped, and the cost is inevitable. .

  Further, in the conventional DC motor, as shown in FIG. 13, slits 4c 'and 4c' provided in the side wall portion of the brush holder 4 'are opened on the radially outer side (the commutator 2 side) of the brush holding plate 3'. In this case, however, the brush 5 is worn, and the spring 7 (see FIG. 11) for biasing the brush 5 closes the end of the slit 4c ′ on the commutator 2 side of the side wall 4a2 ′ of the guide holder. When it comes into contact with the terminal portion (the end portion on the commutator side), the brush cannot be urged, so that the brush cannot be used any more and the life of the DC motor is shortened. In order to extend the life of the brush and the life of the motor, it is necessary to shorten the length d of the end portion of the side wall portion 4a2 'of the brush holder that closes the end of the slit 4c' on the commutator 2 side. However, due to the mechanical strength of the brush holder, there is a limit to shortening the length d of the end portion of the side wall portion 4a2 ′, and there is a limit to extending the life of the motor.

  Further, in the conventional DC motor, when the brush 5 is mounted, the brush 5 is put into the brush holder from the rear end side (the end side opposite to the commutator) fixed to the brush holding plate. Since it was necessary to insert the brush, it was necessary to provide a margin for the length of the pigtail 6 connected to the brush in order to handle the brush. Therefore, it is inevitable that the pigtail 6 is slackened after the brush is mounted, and it is necessary to form the pigtail in order to prevent the slacked pigtail from coming into contact with the armature coil of the rotor arranged on the front side of the paper in the drawing. It was troublesome. In addition, the loose pigtail occupies a considerable space between the brush holding plate and the rotor coil, so if the axial dimension of the motor is shortened to reduce the thickness of the motor, the loose pigtail is required. Existence of the electric motor becomes one of the restrictions, and the thinning of the electric motor may be prevented.

  The object of the present invention is to eliminate the need to use an expensive injection molding machine capable of insert molding with a slide jig when molding the brush holding plate and the brush holder, and to reduce the manufacturing cost. An object of the present invention is to provide a direct current motor which is versatile and can reduce the cost of a brush holding plate by mass production.

  Another object of the present invention is to provide a direct current motor that can extend the life by allowing the brush to be used to the limit.

  Another object of the present invention is to shorten the length of the pigtail connected to the brush as compared to the prior art, thereby eliminating the need for the pigtail molding operation after mounting the brush, reducing the number of manufacturing steps, and reducing the space occupied by the pigtail. An object of the present invention is to provide a DC motor that can be reduced in size by reducing the axial dimension.

  Still another object of the present invention is to provide a direct current motor that can be easily adapted to the use of brushes having various shapes and dimensions by easily changing the shape of the brush holder.

  The direct current motor targeted by the present invention is held on the surface side of the brush holding plate so as to extend in the radial direction of the commutator, the brush holding plate disposed outside the radial direction of the commutator, and the commutator. A brush holder and a brush that is slidably held in the brush holder and brought into contact with the commutator are provided. The brush holder is provided with a slit extending along the radial direction of the commutator, and the pigtail connected to the brush is led out of the brush holder through the slit, and is held by the brush holding plate and has an end portion formed in the slit. The brush in the brush holder is biased toward the commutator by the inserted spring.

  In the present invention, the brush holder is configured separately from the brush holding plate, and a coupling portion is provided between the brush holder and the brush holding plate that fits each other and couples the brush holder to the brush holding plate. The brush holder is coupled to the brush holding plate via the coupling portion. Moreover, the slit provided in the brush holder is provided in a state where the end located on the side opposite to the commutator is closed and the end on the commutator side is opened to the commutator side.

  As described above, if the brush holder is configured separately from the brush holding plate and the brush holder is attached to the brush holding plate, an expensive molding machine for insert molding the brush holder to the brush holding plate is not required. Therefore, the manufacturing cost can be reduced. Moreover, since the brush holder is molded independently, it can be manufactured with any size and shape without considering insert molding, and can easily respond to changes in the size and shape of the brush. be able to.

  As described above, if the brush holder is configured separately from the brush holding plate, only the brush holder needs to be changed when the shape and dimensions of the brush used are changed, and the brush holding plate changes. Since it is not necessary, the brush holding plate can be provided with versatility, and the cost of the brush holding plate can be reduced by the mass production effect.

  Also, as described above, the brush holder is configured separately from the brush holding plate, and when the rectifying mechanism is assembled so that the brush holder is coupled to the brush holding plate, the brush is disposed on the brush holding plate. Since the brush holder can later be attached to the brush holding plate and the brush can be incorporated into the brush holder, the length of the pigtail connected to the brush can be minimized, and the brush holding plate and the rotor The volume of the space occupied by the pigtail between the coil and the coil can be reduced, and the presence of the pigtail can be prevented from being restricted when the axial dimension of the motor is reduced. Therefore, it is possible to facilitate the design of an electric motor that is thinner than before.

  Further, as described above, when the slit provided in the brush holder is a slit in which the end located on the side opposite to the commutator is closed and the end on the commutator side is opened to the commutator side, The life of the motor can be made longer than before because it can be used until the whole is worn.

  In a preferred aspect of the present invention, the coupling portion is configured to be fitted to each other and coupled to the brush holding plate while being accompanied by a sliding motion of the brush holder along the radial direction of the commutator. .

  The coupling portion that couples the brush holder to the brush holding plate while being accompanied by the sliding movement of the brush holder along the radial direction of the commutator includes, for example, a guide slot that extends along the radial direction of the commutator. , And a guided portion (or a convex portion) that is slidably fitted into the guide slot. In this case, the guide slot and the guided portion can slide in the radial direction of the commutator when fitted to each other, but cannot slide in the axial direction of the commutator (constrained with each other). The guide slot is provided in one of the brush holding plate and the brush holder, and the guided portion is provided in the other of the brush holding plate and the brush holder. The guide slot has an opening at least on the outer peripheral side of the brush holding plate, and is formed so that the guided portion can be received from the outer peripheral side of the brush holding plate.

  In order to position the brush holder at a predetermined position, a concave / convex fitting portion is provided at the coupling portion for fitting the brush holder to each other when the brush holder is in a predetermined position and positioning the brush holder at the predetermined position. It is preferable to keep it.

    In a preferred embodiment of the present invention, the brush holder has a top plate portion and a pair of side wall portions that protrude from the both ends in the width direction of the top plate portion to the same side, and the cross section has a U-shaped cross section. A main body and a pair of projecting portions projecting outward from the respective distal end portions of the pair of side wall portions of the holder main body are integrally provided, and a pair of thin walls are respectively formed at the distal end portions of the pair of side wall portions. By forming the portion, a pair of stepped portions is formed at a position in front of each tip of the pair of side wall portions.

  The brush holding plate is formed with a guide slot comprising a pair of slots extending in parallel along the radial direction of the commutator with one end opened to the outer periphery of the brush holding plate and the other end closed.

  Each of the slots constituting the guide slot has a width dimension that allows the thin wall portion at the tip of the pair of side wall portions of the brush holder to be slidably fitted, and extends in parallel along the radial direction of the commutator. A pair of slit portions and a pair of recesses for slidably fitting the protruding portions at the tip of the pair of side wall portions of the brush holder on the back side of the brush holding plate. The thin wall portion and the overhang portion of the side wall portion are slidably fitted into the slit portion and the concave portion of the pair of slots constituting the guide slot, respectively, and the pair of step portions are slidably applied to the surface of the brush holding plate. It is connected to the brush holding plate in a contacted state and arranged at a specified position.

  Further, the slit provided in the brush holder is provided in the side wall portion of the brush holder with the end located on the side opposite to the commutator closed and the end on the commutator side opened to the commutator side.

  An uneven fitting portion is provided between the brush holder and the brush holding plate that fits each other and positions the brush holder at the specified position when the brush holder is in the specified position. The brush holder is positioned and fixed in a state where the brush holder is disposed at a predetermined position by the fitting of the concave and convex fitting portions.

  As described above, according to the present invention, since the brush holder is configured separately from the brush holding plate and the brush holder is attached to the brush holding plate, it is necessary to insert-mold the brush holder into the brush holding plate. There is no. Therefore, an expensive molding machine is not required, and the manufacturing cost can be reduced. Moreover, since the brush holder is molded independently, it can be manufactured with any size and shape without considering insert molding, and can easily respond to changes in the size and shape of the brush. be able to.

  According to the present invention, since the brush holder is configured separately from the brush holding plate, when the shape and dimensions of the brush used are changed, only the brush holder needs to be changed. There is no need to change. Therefore, versatility can be given to the brush holding plate, and the cost of the brush holding plate can be reduced due to the mass production effect.

  In the present invention, the brush holder is configured separately from the brush holding plate, and the brush holder is coupled to the brush holding plate when assembling the rectifying mechanism, so that the brush is disposed on the brush holding plate. The brush holder can be attached to the brush holding plate and the brush can be incorporated into the brush holder. Therefore, the length of the pigtail connected to the brush can be made the minimum necessary length, and the volume of the space occupied by the pigtail between the brush holding plate and the coil of the rotor can be reduced. This makes it easier to design a thinner electric motor.

  Further, according to the present invention, the slit provided in the brush holder is formed such that the end located on the side opposite to the commutator is closed and the end on the commutator side is opened. Can be used until it wears down, and the life of the motor can be made longer than before.

Hereinafter, a first embodiment of the present invention will be described in detail with reference to FIGS.
FIG. 1 is a plan view showing a state in which a brush is arranged on a brush holding plate in the present embodiment, FIG. 2 is a front view of a main part viewed from the direction of arrow Y2 in FIG. 1, and FIG. FIG. 4 is a plan view showing a state in which the brush holder is attached to the brush holding plate, FIG. 5A is a side view of the brush holder portion seen from the direction of the arrow X5 in FIG. FIG. 5B is a front view of the vicinity of the brush holder as seen from the direction of the arrow Y5 in FIG. FIG. 6 is a cross-sectional view for explaining the concave-convex fitting portion provided at the coupling portion between the brush holder and the brush holding plate, and FIG. 7 is attached with a spring for biasing the brush in the brush holder toward the commutator. FIG. 8 is a plan view showing a state in which a commutator is arranged at the center of the holding plate, and FIG.

  1 to 8, reference numeral 3 denotes a brush holding plate formed in a disk shape, and a hole 3 a for penetrating the commutator 2 (see FIG. 7) is formed at the center of the brush holding plate 3. ing. The brush holding plate 3 is also provided with four guide slots G1 to G4 extending in the radial direction of the plate (the radial direction of the commutator 2) at intervals of 90 degrees. Each guide slot is composed of a pair of slots 301a and 301b extending in parallel along the radial direction of the brush holding plate, and one end of each of the slots 301a and 301b constituting each guide slot opens to the outer periphery of the brush holding plate. The other end is provided so as to terminate at a position in front of the hole 3a.

  As shown in FIG. 2, the slots 301a and 301b constituting each guide slot have a width dimension that allows a thin portion at the tip of a pair of side wall portions of the brush holder described later to be slidably fitted. A pair of slit portions 301a1, 301b1 extending in parallel along the radial direction of the brush holding plate (the radial direction of the commutator 2), and the tension of the tip of the pair of side wall portions of the brush holder on the back side of the brush holding plate It has a pair of recesses 301a2 and 301b2 into which the protruding portion is slidably fitted.

  Between the slots 301a and 301b constituting each of the guide slots G1 to G4, a tongue-like brush holding plate 302 supported by the brush holding plate in a cantilever manner is formed, and a fan-like shape is formed between the guide slots G1 to G4. Holding plate portions 303 to 306 are formed.

  Cylindrical spring supports S1 and S2 are formed on the surface of the holding plate portion 303 between the guide slots G1 and G2 so as to be positioned on the sides of the guide slots G1 and G2 on both sides thereof. Arc-shaped spring guide protrusions C1 and C2 are formed on the sides.

  Further, cylindrical spring supports S3 and S4 are formed on the surface of the holding plate portion 305 between the guide slots G3 and G4 so as to be positioned on the sides of the guide slots G3 and G4 on both sides thereof. Are formed with arcuate spring guide projections C3 and C4. Each spring support is formed with a groove g for receiving one end of the spring.

  A pigtail connection terminal fitting 310 is attached to the surface of the holding plate 304 between the guide slots G2 and G3. The pigtail connection terminal fitting 310 is connected to one end of pigtails 62 and 63 connected to brushes 52 and 53 held in brush holders 42 and 43 respectively connected to guide slots G2 and G3 on both sides thereof. Connection portions 310a and 310b are provided.

  A pigtail connection terminal fitting 311 is attached to the surface of the holding plate portion 306 between the guide slots G4 and G1. Pigtail connection terminal fitting 311 is connected to one end of pigtails 64 and 61 connected to brushes 54 and 51 held in brush holders 44 and 41 coupled to guide slots G4 and G1 on both sides thereof. Portions 311a and 311b are provided. The pigtail connection terminal fittings 310 and 311 are connected to the input terminal of the DC motor.

  At the periphery of the hole 3a at the center of the brush holding plate 3, the tips of the brush holders 41 to 44, which are positioned in front of the guide slots G1 to G4 and connected to the guide slots G1 to G4, respectively, are held. A pair of positioning pins p and q for engaging and fixing each brush holder by engaging from both sides in the width direction of the respective brush holders are formed.

  The holding plate portion 303 formed between the guide slots G1 and G2 of the brush holding plate 3 is formed with a mounting hole h1 penetrating the holding plate portion 303 so as to be positioned in the vicinity of the spring supports S1 and S2. The holding plate portion 305 formed between G3 and G4 is formed with a mounting hole h3 penetrating the holding plate portion 305 so as to be positioned in the vicinity of the spring supports S3 and S4.

  The holding plate portion 304 formed between the guide slots G2 and G3 of the brush holding plate 3 is formed with a mounting hole h2 penetrating the holding plate portion 303 so as to be positioned in the vicinity of the guide slot G3. , G1 is formed with a mounting hole h4 penetrating the holding plate portion 306 so as to be positioned in the vicinity of the guide slot G4. Protrusions 312 and 313 are formed on the periphery of the mounting holes h2 and h4 so as to contact a part of the pigtails 63 and 64 and prevent the pigtails from spreading to the outer peripheral side of the brush holding plate 3, respectively.

  In FIG. 1, a portion indicated by reference symbol a on the brush holding plate portion 302 is an uneven fitting for positioning the brush holders 41 to 44 at predetermined positions together with convex portions provided on the brush holders 41 to 44 described later. It is the recessed part which comprises a part. Although not shown in FIG. 1, a similar recess a is provided on the ceiling surface in the recesses 301 a 2 and 302 b 2 on the back surface of the brush holding plate 3.

  Brush holders 41 to 44 are coupled to the guide slots G1 to G4 of the brush holding plate 3 as shown in FIG. As shown in FIG. 3, each brush holder has a top plate portion 4a1 and a pair of side wall portions 4a2 and 4a2 projecting to the same side from both ends in the width direction of the top plate portion 4a1. A holder body 4a having a U-shape and a pair of projecting portions 4b, 4b projecting outward from the respective tip end portions of the pair of side wall portions of the holder body 4a are integrally formed. A pair of thin portions 4a3 and 4a3 are formed at the tip portions of 4a2 and 4a2, respectively, so that a pair of stepped portions 4a4 and 4a4 are formed at positions in front of the respective tips of the pair of side wall portions. .

  In this example, the thin wall portions 4a3 and 4a3 formed at the front ends of the side wall portions 4a2 and 4a2 of the brush holders 41 to 44, a pair of step portions 4a4 and 4a4, and a pair of overhang portions 4b and 4b. Thus, a guided portion is formed which extends with a uniform cross-sectional shape in the longitudinal direction of the brush holder.

  As shown in FIG. 6, circular recesses a are formed at predetermined positions on the ceiling surface of the recesses 301 a 2 and 301 b 2 of the brush holding plate 3 and at predetermined positions near both ends in the width direction of the brush holding plate 302. Yes. The pair of overhanging portions 4b and 4b and the stepped portions 4a4 and 4a4 of the brush holders 41 to 44 are provided with recesses 301a2 of the brush holding plate 3 when the brush holders 41 to 44 slide to reach a predetermined position. The convex part b which each fits into the recessed part a provided in the ceiling surface of 301b2 and the recessed part a provided in the brush holding plate part 302 is formed, and the uneven | corrugated fitting part comprised by these recessed parts a and the convex part b Thus, the brush holders 41 to 44 are positioned and fixed at specified positions.

  When assembling the above rectifying mechanism, first, as shown in FIG. 1, the brush 51 is placed on the brush holding plate portion 302 formed between the pair of slots 301a and 301b constituting the guide slots G1 to G4. To 54, and the other ends of the pigtails 62 and 63, one end of which is connected to the brushes 52 and 53, respectively, are connected to the pigtail connection portions 310a and 310b of the pigtail connection terminal fitting 310. Further, the other ends of the pigtails 64 and 61 whose one ends are connected to the brushes 54 and 51 are connected to the pigtail connection portions 311 a and 311 b of the pigtail connection terminal fitting 311.

  Next, the guided portions formed at the front end portions of the side wall portions 4a2 and 4a2 of the brush holders 41 to 44 are fitted into the corresponding guide slots G1 to G4 from the outer diameter side of the brush holding plate 3, and the brushes 51 to 54 is inserted into the brush holders 41 to 44, and pigtails 61 to 64 respectively connected to the brushes 51 to 54 are inserted into any one of the slits 4c of the brush holders 41 to 44 so that the brush holders 41 to 44 are brushed. Slide toward the inside of the holding plate in the radial direction. At this time, as shown in FIG. 5B, the thin-walled portions 4a3 and 4a3 and the overhang portions at the tips of the pair of side wall portions 4a2 and 4a2 constituting the guided portions of the brush holders 41 to 44, respectively. 4b and 4b are fitted into the slits 301a1 and 301b1 and the recesses 301a2 and 301b2 of the pair of slots constituting the guide slots G1 to G4, respectively, and the pair of stepped portions 4a4 and 4a4 is inserted into the slot 301a of the corresponding guide slot. , 301b are brought into contact with both ends in the width direction of the brush holding plate portion 302 formed between them. The brush holders 41 to 44 are positioned in the radial direction of the brush holding plate by fitting the thin wall portions 4a3 and 4a3 at the front ends of the respective side wall portions with the corresponding narrow gap portions 301a1 and 301b1, and the overhang portions 4b. , 4b and the recesses 301a2 and 301b2 and the stepped portions 4a4 and 4a4 and the brush holding plate 302 are engaged with each other so as not to be displaced in the axial direction of the brush holding plate 3 (the axial direction of the rotating shaft of the motor). In a positioned state, the brush holding plate 3 is coupled.

  When the brush holders 41 to 44 are slid to a predetermined position, the concave portions a and the convex portions b of the concave and convex fitting portions provided between the brush holder and the brush holding plate are fitted to each other, and the brush holders 41 to 44 are fitted. Positioning. The specified position of the brush holder in the present embodiment is a position where the tip of each brush holder is aligned with the central hole 3a of the brush holding plate. End surfaces 41a to 44a (see FIG. 4) at the tips of the brush holders 41 to 44 are formed in an arc shape along the circumferential direction of the hole 3a.

  After the brush holders 41 to 44 and the brushes 51 to 54 are attached to the brush holding plate 3 as described above, a spring 7 for urging the brushes 51 to 54 toward the commutator 2 is attached as shown in FIG. The spring 7 for energizing each brush includes a winding portion 7a wound in a coil shape, an extension portion 7b extending from one end of the winding portion 7a in a tangential direction of the winding portion, and an extension portion 7b. An arc-shaped brush engaging portion 7c formed at the tip and a locked portion 7d extending from the other end of the winding portion 7a to the inner diameter side of the winding portion are integrally provided.

  The spring support S1 to S4 is fitted with the winding portion 7a of the spring 7, and the spring supported portion 7d is engaged with the groove g to attach the spring 7 to the spring support S1 to S4. As shown in FIGS. 7 and 8, the brush engaging portions 7c of the springs 7 respectively held on the side surfaces of the brushes 51 to 54 in the brush holders 41 to 44 are passed through the slits 4c provided in the brush holders 41 to 44. Abut. As a result, the brushes 51 to 54 are temporarily held at a position retracted from the hole 3 a of the brush holding plate 3. Next, the brush holding plate 3 is fixed to the end cover of the electric motor arranged on the back side of the paper surface of FIG. 7 with screws inserted into the mounting holes h1 to h4, and a bearing attached to one end of the rotary shaft 1 of the rotor is attached. While being held by a bearing holding portion provided in the end cover, the commutator 2 attached to the rotary shaft 1 is disposed through the central hole 3 a of the brush holding plate 3. Next, the brushes 51 to 54 disposed in the brush holders 41 to 44 and temporarily held by the spring 7 are pushed from the opening on the outside of the brush holders 41 to 44 (the outer diameter side of the brush holding plate 3), and the brush 51 to 54 are displaced to a position where they abut against the commutator 2, and the brush engaging portions 7 c of the springs 7 are brought into contact with the rear end portions of the corresponding brushes, as in the conventional example shown in FIG. 51 to 54 are biased toward the commutator 2 by a spring 7 provided for each. Thereafter, a rotor is inserted inside a stator provided in an electric motor case (not shown), and a bearing attached to the other end of the rotating shaft 1 is held by a bearing holding portion provided on the bottom wall portion of the case, An end cover is coupled to the opening of the case to complete the electric motor.

  The commutator 2, the brush holding plate 3, the brush holders 41 to 44, the brushes 51 to 54, and the spring 7 constitute a rectifier mechanism, and the rectifier mechanism, a rotor and a stator (not shown) constitute a DC motor. Is done.

  As shown in the above embodiment, in the present invention, the brush holders 41 to 44 are configured separately from the brush holding plate 3, and are fitted to each other so that the brush holders 41 to 44 are connected to the brush holding plate 3. Are coupled between the brush holders 41 to 44 and the brush holding plate 3, and the brush holders 41 to 44 are coupled to the brush holding plate via the coupling portions. In addition, the slits 4c and 4c provided in the brush holders 41 to 44 are provided in a state where the end located on the opposite side to the commutator 2 is closed and the end on the commutator 2 side is opened to the commutator side. .

  In the present invention, the coupling portion is fitted to each other while the sliding movement of the brush holders 41 to 44 along the radial direction of the commutator 2 is performed to couple the brush holders 41 to 44 to the brush holding plate 3. It is configured as follows.

  As also shown in the above embodiment, the coupling portion includes guide slots G1 to G4 provided on one of the brush holding plate 3 and the brush holders 41 to 44 so as to extend along the radial direction of the commutator 2. The guide portions (thin portions 4a3, 4a3, overhang portions 4b, 4b, and overhang portions 4a3, 4a3, which are formed on the other of the brush holding plate 3 and the brush holders 41 to 44 and are slidably fitted into these guide slots. Preferably, it is constituted by stepped portions 4a4, 4a4). In this case, the guide slot and the guided portion can be relatively slid in the radial direction of the commutator while being fitted to each other, but cannot be relatively slid in the axial direction of the commutator. It is configured to have a cross-sectional shape. The guide slot has an opening at least on the outer peripheral side of the brush holding plate, and is formed so that the guided portion of the brush holder can be received from the outer peripheral side of the brush holding plate.

  As described above, when the brush holders 41 to 44 are configured separately from the brush holding plate 3 and the brush holders 41 to 44 are attached to the brush holding plate, it is necessary to insert-mold the brush holder into the brush holding plate. Therefore, an expensive molding machine is not required, and the manufacturing cost can be reduced. Further, since the brush holders 41 to 44 can be manufactured with free dimensions and shapes without considering insert molding, it is possible to easily cope with changes in the dimensions and shapes of the brushes. .

  If the brush holders 41 to 44 are configured separately from the brush holding plate 3 as described above, only the brush holder needs to be changed when the shape and dimensions of the brush to be used are changed. Since it is not necessary to change -44, the versatility can be given to a brush holding plate, and cost reduction can be aimed at.

  As described above, when the brush holder is configured separately from the brush holding plate and the brush holder is coupled to the brush holding plate when assembling the rectifying mechanism, the brushes 51 to 54 are disposed on the brush holding plate 3. After that, the brush holders 41 to 44 can be attached to the brush holding plate 3 and the brushes 51 to 54 can be incorporated into the brush holders 41 to 44. Therefore, the length of the pigtails 61 to 64 to be connected to the brushes 51 to 54 can be set to the minimum necessary length, and the volume of the space occupied by the pigtail between the brush holding plate and the rotor coil can be reduced. Thus, it is possible to easily design a motor that is thinner than the conventional one.

  Further, as in the above embodiment, when the slits 4c and 4c provided in the brush holder are formed so that the end located on the side opposite to the commutator is closed and the end on the commutator side is opened, the brushes 51 to 54 are respectively formed. Therefore, the life of the electric motor can be made longer than before.

  In the above embodiment, the thin wall portions 4a3 and 4a3 and the overhang portions 4b and 4b are provided at the tips of the pair of side wall portions 4a2 and 4a2 of the brush holders 41 to 44, respectively. The pair of slots of the pair of slots constituting the guide slot of the brush holding plate 3 are slidably fitted in the slits and recesses, and the pair of stepped portions 4a4 and 4a4 are slidably brought into contact with the surface of the brush holding plate. In this state, the brush holders 41 to 44 are coupled to the brush holding plate. However, in the present invention, the coupling portion for coupling the brush holders 41 to 44 to the brush holding plate 3 is along the radial direction of the commutator 2. A guide slot provided in one of the brush holding plate 3 and the brush holders 41 to 44 so as to extend, and a shape that is slidably fitted in the guide slot And the guided portion provided on the other side of the brush holding plate and the brush holder, and the guide slot and the guided portion are relatively fitted in the radial direction of the commutator in a state in which the guide slot and the guided portion are fitted to each other. Although it can slide, it should just be comprised so that it may have a cross-sectional shape which cannot slide relatively in the axial direction of a commutator, and it is not limited to the thing of the said embodiment.

  FIG. 9 and FIG. 10 show a second embodiment of the present invention showing a modified example of the coupling portion between the brush holder and the brush holding plate. In this embodiment, the side wall 4a2 of the brush holders 41 to 44 is shown. , 4a2 are formed with inclined surfaces 4e1 and 4e1 on the protruding portions 4e and 4e that protrude outward from the tip. On the other hand, the brush holding plate 3 has a pair of slots 301a 'shaped so that the tips of the side walls 4a2, 4a2 of the brush holders and the overhanging parts 4e, 4e can be slidably fitted to the portions to be connected to the brush holders. Guide slots G1 'to G4' comprising 301b 'are formed, and the brush holder 41 is fitted by fitting the respective tips and overhang portions 4e, 4e of the brush holders 41 to 44 into the corresponding slots 301a' and 301b '. ˜44 are coupled to the brush holding plate 3.

  In order to position the brush holder at the specified position, the concave portion a and the convex portion b that fit together when the brush holder is slid to the specified position are the end surfaces of the overhang portions 4e and 4e and the bottom surfaces of the slots 301a 'and 301b'. Are provided respectively.

  In the above embodiment, four brushes are provided, but the number of brushes is appropriately set depending on the configuration of the armature coil provided in the rotor of the electric motor.

  In the above embodiment, the brush holding plate 3 is formed in a disc shape so as to surround the commutator from the outside, but the brush holding plate may be any one that can hold the required number of brush holders, The contour shape is arbitrary. For example, when only two brushes are provided, the brush holding plate can be formed in a shape having an arcuate inner periphery that faces only a part of the commutator in the circumferential direction.

In the 1st Embodiment of this invention, it is the top view which showed the state which has arrange | positioned the brush on the brush holding plate. It is a front view of the principal part seen from the arrow Y2 direction of FIG. It is a perspective view of the brush holder used by this embodiment. It is the top view which showed the state which attached the brush holder to the brush holding plate. (A) is the side view which looked at the brush holder part from the arrow X5 direction of FIG. 4, (B) is the front view of the brush holder vicinity seen from the arrow Y5 direction of FIG. It is sectional drawing for demonstrating the uneven | corrugated fitting part provided in the coupling | bond part of a brush holder and a brush holding plate. It is the top view which showed the state which attached the spring which urges | biases the brush in a brush holder toward a commutator, has arrange | positioned the commutator in the center of a brush holding plate, and completed the commutation mechanism. It is a front view of the principal part seen from the arrow Y8 direction of FIG. It is a perspective view of the brush holder used in the 2nd Embodiment of this invention. It is sectional drawing which showed the state which couple | bonded the brush holder with the brush holding plate in the 2nd Embodiment of this invention. It is a top view of the straightening mechanism used with the conventional DC motor. It is the front view of the principal part seen from the arrow Y12 direction of FIG. It is the side view of the principal part seen from the arrow X13 direction of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rotating shaft 2 Commutator 3 Brush holding plate G1-G4 Guide slot 301a, 301b A pair of slot which comprises a guide slot 41-44 Brush holder 4a2 Side wall part of a brush holder 4a3 Thin part of the side wall part of a brush holder 4a4 Step part 4b Overhang 4c Slit 51-54 Brush 61-64 Pigtail

Claims (5)

A commutator, a brush holding plate disposed outside the commutator in the radial direction, a brush holder held on the surface side of the brush holding plate so as to extend in the radial direction of the commutator, and the brush holder A brush that is slidably held in contact with the commutator, and a slit extending in a radial direction of the commutator is provided in the brush holder, and the pigtail connected to the brush is A direct current that is led out of the brush holder through a slit and is urged toward the commutator by the spring held by the brush holding plate and having an end inserted into the slit. In the electric motor,
The brush holder is configured separately from the brush holding plate,
A coupling portion that fits together and couples the brush holder to the brush holding plate is provided between the brush holder and the brush holding plate, and the brush holder is connected to the brush holding plate via the coupling portion. Combined,
The slit provided in the brush holder is provided in a state where the end located on the side opposite to the commutator is closed and the end on the commutator side is open on the commutator side,
DC motor characterized by   The said coupling | bond part is comprised so that it may mutually fit and couple | bond the said brush holder to a brush holding plate, accompanied by the sliding motion of the said brush holder along the radial direction of the said commutator. The described DC motor. The coupling portion is provided in one of the brush holding plate and the brush holder so as to extend along the radial direction of the commutator, and is provided in the other of the brush holding plate and the brush holder. And a guided portion formed so as to be slidably fitted into the guide slot,
The guide slot and the guided portion can slide relative to each other in the radial direction of the commutator while being fitted to each other, but cannot slide relative to the axial direction of the commutator. Configured to have a cross-sectional shape,
The guide slot has an opening at least on an outer peripheral side of the brush holding plate, and is formed so as to be able to receive a guided portion from the outer peripheral side of the brush holding plate. 2. The DC motor according to 2.   The concave and convex fitting portions that are fitted to each other and position the brush holder at a predetermined position when the brush holder is in a predetermined position are provided at the coupling portion. The DC motor according to 2 or 3. A commutator, a brush holding plate disposed outside the commutator in the radial direction, a brush holder held on the surface side of the brush holding plate so as to extend in the radial direction of the commutator, and the brush holder A brush that is slidably held in contact with the commutator, and a slit extending in a radial direction of the commutator is provided in the brush holder, and the pigtail connected to the brush is A direct current that is led out of the brush holder through a slit and is urged toward the commutator by the spring held by the brush holding plate and having an end inserted into the slit. In the electric motor,
The brush holder includes a holder body having a top plate portion and a pair of side wall portions protruding to the same side from both ends in the width direction of the top plate portion, and having a U-shaped cross section; A pair of protruding portions projecting outward from the respective distal end portions of the pair of side wall portions are integrally formed, and a pair of thin portions are formed at the distal end portions of the pair of side wall portions, respectively. Thus, a pair of stepped portions is formed at a position in front of each tip of the pair of side wall portions,
The brush holding plate is formed with a guide slot consisting of a pair of slots extending in parallel along the radial direction of the commutator with one end opened to the outer periphery of the brush holding plate and the other end closed. ,
Each slot constituting the guide slot has a width dimension in which the thin wall portion at the tip of the pair of side wall portions of the brush holder can be slidably fitted, and is parallel to the radial direction of the commutator. A pair of extending slits and a pair of recesses for slidably fitting the protruding portions at the ends of the pair of side walls of the brush holder on the back side of the brush holding plate;
The brush holder is configured such that the thin wall portions and the overhang portions of the pair of side wall portions are slidably fitted into the slit portions and the recess portions of the pair of slots constituting the guide slot, respectively, and the pair of step portions Is slidably contacted with the surface of the brush holding plate and is coupled to the brush holding plate and disposed at a specified position.
The slit is provided on the side wall of the brush holder with the end located on the side opposite to the commutator closed and the end on the commutator side opened to the commutator side,
A concave / convex fitting portion is provided between the brush holder and the brush holding plate that fits each other and positions the brush holder at a predetermined position when the brush holder is in a predetermined position. thing,
DC motor characterized by

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