JP2009207326A - Commutator for motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To strengthen an impact resistance by suppressing the movement of a commutator segment even if a holding force of a commutator washer is reduced, and to increase a mechanical strength of the entire commutator by making it hard to be affected by the external environment regardless of the presence of a rubber ring resistance, when used for a long period of time or under a severe environmental condition (high temperature and high humidity). <P>SOLUTION: A segment stopper is provided which protrudes from both sides in the circumferential direction of a commutator terminal of each commutator segment, and a segment stopper recess is formed between each pair of adjacent segment stoppers. A core protrusion fitted to the segment stopper recess is provided at a commutator core. The movement of the commutator segment in thrust and circumferential directions with respect to the commutator core is regulated by fitting this core protrusion into the segment stopper recess. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a commutator for a motor in which a commutator washer is press-fitted and fixed on a commutator segment disposed on the outer periphery of a commutator core.

  A commutator of a small motor is configured by locking a commutator segment disposed on a commutator core by a commutator washer. FIG. 6 is a diagram showing a commutator according to the prior art (see Patent Document 1). As shown in the figure, a rubber ring resistor and a metal commutator segment are fixed to a resin commutator core fixed to the motor shaft by a resin commutator washer. The rubber ring resistor is brought into close contact with the commutator terminal by heat generated when welding a connecting wire of a winding wound around the commutator terminal formed integrally with the commutator segment. The rubber ring resistance is used as a spark erasing means for suppressing a spark generated between the commutator segment and the brush.

  The commutator may be permanently deformed in the inner diameter of the commutator and washer under long-term use or severe environmental conditions (high temperature and high humidity), and the holding power of the commutator components may be reduced. As a result, disconnection of the commutator terminal connection line due to movement of the commutator segment or contact with the brush of the commutator washer is a concern. As described above, in the method in which the commutator washer is simply press-fitted and fixed, it is difficult to hold the commutator components when the press-fitting holding force is reduced.

Further, when a rubber ring resistor is used, the rubber ring resistor is fixed by applying heat to the commutator terminal, but the commutator core and the rubber ring resistor are not mechanically fixed. There is no mechanical fixing between the commutator core and the rubber ring resistance and between the commutator core and the commutator segment. For this reason, when a mechanical shock is applied in the thrust direction, there is a concern that the commutator washer or the commutator segment may move in the thrust direction (motor shaft axis direction).
Japanese Utility Model Publication No. 62-84365

  The present invention solves such a problem and suppresses the movement of the commutator segment even in a state where the holding power of the commutator washer is reduced in a long-term use or severe environment condition (high temperature and high humidity). Therefore, the object is to enhance the mechanical strength of the entire commutator regardless of the presence or absence of the rubber ring resistance by enhancing impact resistance and making it less susceptible to the influence of the external environment.

  A commutator for a motor of the present invention includes a commutator core, a plurality of commutator segments having a commutator terminal at one end, and a commutator washer that is press-fitted and fixed to the outer periphery of the commutator segment disposed on the outer periphery of the commutator core. Have A segment stop is provided between each two adjacent segment stops, with segment stops protruding from both sides in the circumferential direction of the commutator terminal of each commutator segment. A core convex portion that fits into the segment stopper concave portion is provided on the commutator core. By fitting the core convex portion into the segment stop concave portion, the thrust direction and circumferential movement of the commutator segment with respect to the commutator core are restricted.

  The segment stopper is formed so as to protrude further in the thrust direction than the root portion of the commutator segment on one end in the thrust direction of the commutator segment and on both sides in the circumferential direction of the commutator terminal integrally formed with the root portion at the circumferential center. This segment stopper is constituted by an L-shaped claw portion formed by cutting out a side surface facing the core convex portion.

  Washers are provided on both sides of each commutator segment in the circumferential direction to restrict thrust direction movement of the commutator washer that is press-fitted and fixed to the outer circumference of the commutator segment. This washer stop is constituted by a step formed by cutting out the commutator segment at a position corresponding to the thrust direction position of one end of the commutator washer.

  In the commutator core, a cylindrical core body portion and a core wall portion that support the commutator segment on the surface thereof are integrally formed by resin molding, and the core wall portion has a commutator segment and a commutator washer on its side surface. Is positioned in the thrust direction. The core wall portion includes a washer contact portion for positioning the commutator washer in the thrust direction, and a terminal contact portion for positioning the commutator terminal in the thrust direction, and the commutator terminal is connected to the terminal contact portion and the commutator washer. Fix it with a pinch. The segment stopper is inserted into the gap between the core convex portion and the terminal contact portion. The rubber ring resistor is inserted between the commutator core wall and the commutator terminal and is brought into close contact with the commutator terminal.

  According to the present invention, since the commutator segment is mechanically fixed to the commutator core, the inner diameter distortion of the commutator washer occurs, and the commutator-washer holding force is reduced. Segment movement is suppressed.

  In addition, according to the present invention, since the commutator segment and the commutator core are mechanically held, the impact resistance is strong and it is difficult to be influenced by the external environment. For this reason, it is also possible to suppress deformation of the rubber ring resistance. Furthermore, the strength of the entire commutator can be increased regardless of the presence or absence of the rubber ring resistance.

  Hereinafter, the present invention will be described based on examples. FIG. 1 is a partial cross-sectional view showing a small motor incorporating a commutator as a feature of the present invention in an upper half cross section. As shown in the drawing, a magnet is attached as a field pole to the inner peripheral surface of a motor case pressed into a bottomed hollow cylindrical shape with a metal material. A metal motor case having a substantially constant plate thickness forms a yoke serving as a magnetic path of the magnet. The motor housing is constituted by the motor case and a case lid fitted in the opening. The motor shaft of the rotor is supported by bearings provided at the center of the case lid and at the center of the bottom of the motor case. The rotor configured on the motor shaft has a rotor magnetic pole configuration including a laminated core and a winding wound on the magnetic pole core. A commutator, which will be described in detail later, is fixed on the motor shaft. A pair of brushes (not shown) that come into contact with the commutator is supported by the case lid via the brush arm and supplied with power from the outside via a pair of external terminals (not shown) connected to the brush arm. The

  FIG. 2 is a view showing a commutator that is a feature of the present invention. FIG. 2 is a partial sectional view (A), a side view (B), and an inter-segment slit side showing the upper half of the commutator after assembly. It is a top view (C). The illustrated commutator includes a commutator segment, a commutator core, and a commutator washer, and a rubber ring resistor is incorporated as necessary. When assembling, the commutator washer is pressed into the commutator core from the state where the outer periphery of the commutator core and the inner periphery of the commutator segment are combined. Direction). In the illustrated example, three commutator segments for the three rotor poles are equally spaced on the commutator core with slits therebetween. In each commutator segment made of metal (conductive member), a commutator terminal rises integrally from its root portion, and a tip end side of the commutator terminal is bent, and a winding end is connected thereto. The commutator washer for fixing the commutator segment to the commutator core has its inner diameter portion locked to the root portion of the commutator segment. When incorporating a rubber ring resistor, insert the rubber ring resistor between the commutator core wall and the commutator terminal. This rubber ring resistance is brought into close contact with the commutator terminal by heat generated when welding the winding end wound around the commutator terminal.

  FIG. 3 is a diagram showing the commutator core in detail, (A) is a front view showing a part of the wall part broken to show the segment stopper insertion position, and (B) is a side view thereof. It is. In the commutator core, a cylindrical core main body portion that supports the commutator segment on the surface thereof and a core wall portion are integrally formed by resin molding. The core wall positions the rubber ring resistance, commutator segment, and commutator washer on its side. The washer contact portion of the core wall portion positions the commutator washer in the thrust direction, and the terminal contact portion positions the commutator terminal in the thrust direction (and circumferential direction). As a result, the commutator terminal is sandwiched and fixed between the terminal contact portion and the commutator washer. When the rubber ring resistor is used, the rubber ring resistor is fixed by being sandwiched between the terminal contact portion and the commutator terminal. The plurality of positioning protrusions provided at the end of the commutator core are inserted into grooves provided in the laminated core, thereby positioning the commutator in the thrust direction and the circumferential direction with respect to the laminated core on the motor shaft. As a result, the commutator / core cylindrical portion between the core wall portion and the positioning projection enters the inner diameter side of the winding protruding on the side surface.

  The illustrated commutator core having such a configuration is integrally formed with a core projection for positioning and fixing the commutator segment. The number of core protrusions is the same as the number of commutator segments, and is fitted between two adjacent segment stops (see FIG. 4) of the commutator segments. The core convex part formed integrally on the commutator core has a radial height higher than that of the cylindrical main body, and as will be described in detail later, the segment stopper of each commutator segment is provided on each of both side surfaces. Lock. Each segment stopper is inserted into a gap between the core convex portion and the terminal contact portion. The washer abutting portion is located between the terminal abutting portions in the circumferential direction and is located above the segment stopper inserted in the radial direction. Moreover, the segment positioning part inserted in a slit can be provided in the circumferential direction center of a core convex part toward the slit direction between segments.

  4A and 4B are diagrams showing details of the commutator segment, in which FIG. 4A is a plan view viewed in a state of being placed on the commutator core, and FIG. 4B is a side view thereof (however, (Only one commutator terminal is shown in detail, and the remaining two are simply shown) (C) is a view of one commutator segment from the side, and (D) is ( It is a figure which expands and shows the X section shown to C). A commutator terminal rises integrally from one end in the thrust direction of the commutator segment and the central portion (root portion) in the circumferential direction, and segment stoppers that project from both sides in the circumferential direction are integrally formed. The segment stopper protrudes further in the thrust direction than the root portion of the commutator segment and forms an L-shaped claw portion on the side surface thereof. The L-shaped claw portion can be formed by cutting out the side of the segment stopper facing the core convex portion. Thus, when the above-described core convex portion is fitted into the segment stopper concave portion (FIG. 4A) to be formed between each two adjacent segment stoppers, this L-shaped claw The portion is fixed so as to bite into the resin constituting the core convex portion.

  Further, the radially outer peripheral portion of the commutator segment disposed on the commutator core is fixed by a commutator washer. The illustrated commutator segment is provided with a washer stopper. This washer stopper can be constituted by a step formed at the end of the notch for forming the above-mentioned L-shaped claw portion. The thrust direction position of this step (washer stop) coincides with one end of the washer position as shown by a dotted line in FIG. 4A (the other end in the thrust direction of the washer position coincides with the commutator terminal root position). ). When a resin commutator washer with a circular inner diameter is press-fitted onto a metal commutator segment, the movement of the commutator washer on the commutator segment is restricted by the resin that has been press-fitted into the step. Will be.

  FIG. 5 is an exploded view of components constituting the commutator of FIG. 2, and (B) is shown in a state rotated by 60 ° with respect to (A). The components configured as described above are assembled in the positional relationship shown in FIG. If a rubber ring resistor is used, it is first inserted on the commutator core. Next, a commutator washer is press-fitted from a state in which the outer periphery of the commutator core and the inner periphery of the commutator segment are combined to fix the commutator segment in the circumferential direction and the thrust direction on the commutator core. At this time, as described above, the thrust of the commutator segment on the commutator core and the movement in the circumferential direction are caused by fitting the core convex part into the segment stopper concave part and causing the segment stopper to bite into the core convex part. Be regulated. Then, the commutator washer is fixed to the commutator core by press-fitting the commutator washer into the root of the commutator segment. At this time, the movement of the commutator washer on the commutator segment is restricted by locking the circular inner diameter portion of the commutator washer with a washer stopper.

It is a fragmentary sectional view which shows the small motor incorporating the commutator which is the characteristics of this invention in an upper half cross section. It is a figure which takes out and shows the commutator which is the characteristics of this invention, and is a fragmentary sectional view (A) which shows the upper half of a commutator after an assembly in a section, a side view (B), and a top view (C) ). It is a figure which shows a commutator core in detail, (A) is a front view which fractures | ruptures and shows a part of wall part, (B) is the side view. It is a figure which shows the detail of a commutator segment, (A) is the top view seen in the state arrange | positioned at a commutator core, (B) is the side view, (C) is one piece It is the figure which looked at the commutator segment of this from the side, (D) is the figure which expands and shows the X section shown to (C). FIG. 3 is an exploded view of components constituting the commutator of FIG. 2, and (B) shows a state rotated by 60 ° with respect to (A). It is a figure which shows the commutator by a prior art.

Claims (9)

A commutator for a motor having a commutator core, a plurality of commutator segments having a commutator terminal at one end, and holding means for press-fitting and fixing to the outer periphery of the commutator segment disposed on the outer periphery of the commutator core.
A segment stopper that protrudes on both sides in the circumferential direction of the commutator terminal of each commutator segment, and a segment stopper recess is formed between each two adjacent segment stoppers;
A core convex portion that fits into the segment stop concave portion is provided in the commutator core,
A motor commutator comprising restricting movement of the commutator segment in the thrust direction and circumferential direction relative to the commutator core by fitting the core convex portion into the segment stopper concave portion. The motor commutator according to claim 1, wherein the segment stopper in at least one commutator segment is configured by an L-shaped claw portion formed by cutting out a side surface facing the core convex portion. The motor commutator according to claim 2, wherein the L-shaped claw portion bites into the core convex portion. The holding means for press-fitting and fixing to the outer periphery of the commutator segment is a commutator washer, and is provided with washer stoppers on both sides in the circumferential direction of each commutator segment to restrict movement of the commutator washer in the thrust direction. Item 4. The motor commutator according to Item 3. 5. The motor commutator according to claim 4, wherein the washer stopper is configured by a step formed by cutting out the commutator segment at a position corresponding to a thrust direction position of one end of the commutator washer. In the commutator core, a cylindrical core main body portion and a core wall portion that support the commutator segment on the surface thereof are integrally formed by resin molding, and the core wall portion has a commutator segment and a commutator The motor commutator according to claim 4, wherein the washer is positioned in a thrust direction. The core wall includes a washer contact portion for positioning the commutator washer in the thrust direction, and a terminal contact portion for positioning the commutator terminal in the thrust direction, and the commutator terminal is connected to the terminal contact portion and the commutator washer. The motor commutator according to claim 4, wherein the motor commutator is sandwiched and fixed. The motor commutator according to claim 7, wherein the segment stopper is inserted into a gap between the core convex portion and the terminal contact portion. The motor commutator according to claim 4, wherein a rubber ring resistor is inserted between the commutator core wall portion and the commutator terminal so as to be in close contact with the commutator terminal.

Images