JP2014099951A - Commutator motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a commutator motor capable of easily checking a brush spring inserted in a brush through a check hole while assembling the commutator motor, to thereby easily detect shortage of the brush spring when a commutator motor in which the brush spring is not inserted into guide occurs.SOLUTION: The commutator motor has: a rotor 20; a pair of guides 40; a brush 43 and a brush spring 44 of an elastic member stored in each of the guides 40; and a holding member 4. The guide 40 has a path 48 and a check hole 49. The path 48 allows a brush 43 to move along a radial direction R thereinside. The check hole 49 is located at a position where the brush spring 44 of an elastic member is disposed and is position along the center line of the path 48.

Description

  The present invention relates to a commutator electric motor used for household vacuum cleaners, electric tools, automobile electrical equipment, and the like.

  In recent years, commutator motors used for household vacuum cleaners, electric tools, automobile electrical equipment, and the like have been improved in efficiency, long life, and high reliability. In order to satisfy these requirements, carbon brushes (hereinafter referred to as brushes) are required to have low resistance loss, low wear, and high reliability.

  Conventionally, a brush is inserted into a brush holder (corresponding to the “guide” of the present invention, hereinafter referred to as “guide”). The guide is formed in a box shape from brass or a resin material. The guide has an opening at one end. The guide has a long hole on a side surface. The opening is installed to face a commutator provided in the rotor. The brush is inserted into the guide together with the brush spring. A brush that is inserted into the guide together with the brush spring is referred to as a brush portion. The brush is pressed against the commutator through the opening by the elastic force of the brush spring.

  The brush has a pigtail. The pigtail is led out of the guide through a long hole formed in the side surface of the guide. The current supplied from the outside of the commutator motor via the pigtail is guided to the commutator through the brush (see, for example, Patent Document 1).

JP-A-1-103141

  However, when the guide described in Patent Document 1 is used, there are the following problems.

  That is, when the brush is inserted into the guide, the brush spring may not be inserted into the guide. Even if the brush part is assembled without inserting the brush spring, the brush is pressed against the commutator provided on the rotor. This is because the brush is pressed against the commutator by the elastic force of the pigtail that the brush has.

  Even if a brush portion into which a brush spring is not inserted is used at a site where the commutator motor is assembled, the commutator motor incorporating the brush portion may pass assembly inspection. This is because since the brush and the commutator are in contact with each other, there is no problem in energization from the brush to the commutator.

  Thereafter, the commutator motor is shipped from the assembly site to the market, and the commutator motor is used for a corresponding period. When a commutator motor is used, the brushes wear. When the brush wear progresses, it becomes difficult to press the brush against the commutator only with the elastic force of the pigtail. As a result, there has been a problem that the commutator motor does not operate before reaching a preset brush life.

  The present invention has been made to solve the above problems, and detects that a brush spring is not inserted into a guide when a commutator motor is assembled. Therefore, it prevents that the commutator motor in which the brush spring is not inserted is shipped. As a result, the commutator motor can be used until a preset brush life is reached.

  The commutator motor according to the present invention includes a rotor, a pair of guides, a brush, an elastic member, and a holding portion inside each guide. The rotor has a rotating shaft and a commutator, and rotates around the rotating shaft.

  The guide forms a pair of positive and negative electrodes. The guide has an opening at a position facing the commutator. The guide is disposed to face the rotor along the radial direction of the rotor orthogonal to the rotation axis.

  The brush is disposed in each guide of the positive and negative electrodes. The brush is movable along the radial direction in the guide. The brush slides in contact with the commutator on the sliding surface through the opening.

  The elastic member is disposed in each guide of the positive and negative electrodes. The elastic member is disposed in the guide so as to press the brush against the commutator along the radial direction. The guide is formed on the holding portion.

  The guide has a passage and a confirmation hole. In the passage, the brush moves in the radial direction within the passage. The confirmation hole is a position where the elastic member is disposed, and is positioned along the center line of the passage.

  According to the commutator motor of the present invention, when the commutator motor is assembled, the presence or absence of the brush spring inserted into the brush from the confirmation hole can be confirmed. Therefore, when a commutator motor in which no brush spring is inserted into the guide is generated, it can be easily detected that the brush spring is insufficient.

  As a result, it is possible to prevent the commutator motor without the brush spring from being shipped to the market.

1 is a perspective assembly diagram of a commutator motor according to Embodiment 1 of the present invention. Explanatory drawing of the holding | maintenance part of the commutator motor in Embodiment 1 of this invention The perspective view of the brush in Embodiment 1 of this invention 1 is a perspective assembly view of a guide according to Embodiment 1 of the present invention. FIG. 3 is a conceptual perspective view of a guide according to Embodiment 1 of the present invention. Conceptual diagram of main part of holding unit in embodiment 1 of the present invention Sectional drawing of the principal part of the holding | maintenance part in Embodiment 1 of this invention AA line sectional view in FIG. 6 in Embodiment 1 of the present invention. Conceptual diagram of main part of another holding unit according to Embodiment 1 of the present invention Sectional drawing of the principal part of the other holding | maintenance part in Embodiment 1 of this invention The perspective explanatory view of the other guide in Embodiment 1 of the present invention A perspective explanatory view of still another guide according to the first embodiment of the present invention.

  Hereinafter, a commutator motor according to an embodiment of the present invention will be described with reference to the drawings.

(Embodiment 1)
FIG. 1 is a perspective assembly view of a commutator motor according to Embodiment 1 of the present invention. FIG. 2 is an explanatory diagram of a holding part of the commutator motor according to Embodiment 1 of the present invention.

  As shown in FIGS. 1 and 2, the commutator motor 1 includes a rotor 20, a pair of guides 40, a pair of brushes 43, and a brush spring 44, which is a pair of elastic members, in a housing 2. Have. The housing 2 includes a cover 3 and a holding unit 4.

  The commutator motor 1 will be described with reference to FIG. The rotor 20 has a rotating shaft 21 and a commutator 22. The rotor 20 has an armature 23 fixed to the rotating shaft 21. The rotating shaft 21 has bearings 24 at both ends. One bearing 24 is held by the cover 3. The other bearing 24 is held by the holding portion 4. The bearing 24 holds the rotating shaft 21 rotatably. The rotor 20 rotates about the axis 80 of the rotating shaft 21 as the center of rotation. The armature 23 is made of iron or the like. A winding 25 is wound around the armature 23. A driving current is passed through the winding 25 via a commutator 22 from a brush disposed in the guide 40.

  The holding | maintenance part 4 is demonstrated using FIG.

  A pair of guides 40 are disposed in the holding unit 4. A brush 43 and a brush spring 44 are provided in each guide 40. In the drawing, the guide 40A of the positive electrode is provided with a guide cover 42A on the guide base 41A. The positive guide 40A is shown with a part of the guide cover 42A cut away. The negative guide 40B is shown with a guide cover 42B applied to the guide base 41B. Details will be described later. For convenience of explanation, the guide 40, the brush 43, and the brush spring 44 may be referred to when the polarity is not limited. When touching on the polarity, the brush 43A used for the positive electrode, the guide cover 42B used for the negative electrode, and the like may be used. Needless to say, the polarity of the brush 43 and the like is not limited to the following description.

  The guide 40 forms a pair of positive and negative electrodes. The positive electrode guide 40 </ b> A has an opening 45 </ b> A at a position facing the commutator 22. The guide 40 </ b> A is disposed to face the rotor 20 along the radial direction R of the rotor 20 that is orthogonal to the rotation shaft 21.

  The brush 43 is disposed in each of the positive and negative guides 40. The brush 43A is movable along the radial direction R in the guide 40A. The brush 43A slides in contact with the commutator 22 through the opening 45A.

  The brush spring 44, which is an elastic member, is disposed in each of the positive and negative guides 40. The brush spring 44A is disposed in the guide 40A so as to press the brush 43A against the commutator 22 along the radial direction R. The elastic member may be another member as long as it has an appropriate elastic force by pressing the brush 43A.

  Here, the brush 43 </ b> A used for the positive electrode refers to a brush that supplies drive current supplied from outside the commutator motor to the commutator 22. On the other hand, the brush used for the negative electrode refers to a path through which the drive current that has passed through the commutator 22 returns to the outside of the commutator motor. Specifically, the drive current is supplied from the outside of the commutator motor via the terminal 46A. The supplied drive current is guided to the brush 43A through the pigtail 54A. The drive current is supplied to the commutator 22 through the brush 43A pressed against the commutator 22 by the brush spring 44A. On the other hand, the drive current that has been passed through the commutator 22 to the brush in the guide 40B is guided to the terminal 46B via the pigtail 54B. The drive current returns to the power source provided outside the commutator motor via the terminal 46B.

  The guide 40 is formed in the holding part 4.

  Furthermore, it demonstrates in detail using FIGS. 3-10.

  FIG. 3 is a perspective view of the brush 43 according to Embodiment 1 of the present invention. The brush 43 has a rectangular parallelepiped shape. The brush 43 is in contact with the commutator at the sliding surface 51. The brush 43 is chamfered 52 at both ends of the sliding surface 51 in the direction 5 in which the rotor rotates. The brush 43 has a pigtail 54 on the side surface 50. The pigtail 54 is a bundle of copper wires knitted or the like, and has flexibility. The pigtail 54 is a lead wire that supplies a drive current to the brush 43. The pigtail 54 is inserted into a hole provided in the side surface 50 and can be connected by filling the hole with copper powder. The pigtail 54 has a corresponding length. This length is such a length that the brush 43 is continuously used even when the brush 43 is pushed out of the guide by the pressure of the brush spring.

  FIG. 4 is a perspective assembly view of the guide 40 according to Embodiment 1 of the present invention. FIG. 5 is a conceptual perspective view of the guide 40 viewed from an angle different from that in FIG.

  As shown in FIGS. 4 and 5, the guide 40 includes a guide base 41 and a guide cover 42. The guide base 41 is integrally molded with resin together with the holding portion 4. The guide base 41 has a pair of side surfaces, that is, a rib 71 and a bottom surface 72. A space formed by the pair of ribs 71 and the bottom surface 72 forms a passage 48. The brush 43 moves along the radial direction R in the passage 48.

  The guide cover 42 is provided so as to cover the guide base 41, particularly the passage 48. A confirmation hole 49 is formed in the guide cover 42 by cutting a part of the guide cover 42.

  FIG. 6 is a conceptual diagram of a main part of the holding unit according to Embodiment 1 of the present invention. FIG. 6 particularly shows a state where the guide 40 and the commutator 22 are in contact with each other. FIG. 7 is a cross-sectional view of the main part of the holding part according to Embodiment 1 of the present invention. FIG. 7 shows a longitudinal section of FIG. 6 taken along the center line 55. FIG. 8 is a cross-sectional view taken along line AA in FIG. 6 according to Embodiment 1 of the present invention. FIG. 9 is a conceptual diagram of a main part of another holding unit according to Embodiment 1 of the present invention. FIG. 10 is a cross-sectional view of a main part of another holding unit according to Embodiment 1 of the present invention. 9 and 10 show the state changes from FIGS. 6 and 7, respectively. Specifically, the brush 43 is shown as being extended as a result of the brush 43 becoming shorter due to wear with the commutator 22.

  As shown in FIGS. 5 and 6, a brush 43 and a brush spring 44 are inserted into the guide 40. At this time, in the guide cover 42, the confirmation hole 49 is located at a place where the brush spring 44 is disposed. The confirmation hole 49 is located not on the center line 55 of the passage 48 but along the center line 55 of the passage 48.

  The brush spring 44 which is an elastic member in the first embodiment is configured by a spiral spring. As shown in FIGS. 6 and 7, the brush spring 44 has one end in contact with the back surface 53 of the brush 43 and the other end in contact with the back surface 47 of the guide 40. The brush spring 44 is disposed in the guide 40 so as to press the brush 43 against the commutator 22 through the opening 45.

  In the commutator motor according to the first embodiment having the above-described components, the operation of the guide, the brush, the brush spring, etc. will be described.

  6 to 8 show a state where the brush spring 44 is contracted. 9 and 10 show a state where the brush spring 44 is extended.

  As shown in FIGS. 6 to 8, when assembling the commutator motor, the brush 43 is pressed toward the commutator 22 by the brush spring 44 in the guide 40. The brush spring 44 has an elastic force. The brush spring 44 is bent by this elastic force. At this time, the brush spring 44 and the guide 40 are in contact with each other at the contact portion 56. In the present invention, the contact portion 56 refers to the contact between the brush spring 44 and the guide 40 as a result of the brush spring 44 inserted into the guide 40 being bent by the elastic force when the commutator motor is assembled. Say part.

  As shown in FIGS. 2 and 6, the guide cover 42 has a confirmation hole 49 at a position where the brush spring 44 is disposed. The confirmation hole 49 is located not on the center line 55 of the passage 48 but along the center line 55 of the passage 48. In other words, the confirmation hole 49 is positioned adjacent to the contact portion 56 where the guide 40 and the brush spring 44 are in contact with each other along the radial direction R. Further, the confirmation hole 49 is located on the opposite side of the opening 45 of the guide cover 42.

  In this commutator motor, the commutator 22 and the brush 43 are in contact with each other and rub against each other in order to rotate the rotor. As a result, the brush 43 is worn by contact with the commutator 22. As shown in FIGS. 9 and 10, when the brush 43 is worn and shortened, the brush spring 44 extends. The brush spring 44 continues to push the brush 43 toward the commutator 22 with a predetermined pressure.

  With this configuration, the presence of the brush spring 44 can be confirmed from the confirmation hole 49 when the commutator motor is assembled. Therefore, it can be easily detected that the brush spring 44 is inserted into the guide 40.

  In addition, since the confirmation hole 49 is not located on the center line 55 of the passage 48, when the brush spring 44 extends and contracts in the guide 40, there is no problem such that the brush spring 44 is caught in the confirmation hole 49.

  As a result, the commutator motor can be prevented from being shipped without the brush spring 44 being inserted into the guide 40. Thus, the commutator motor is used until a preset brush life is reached.

  In particular, if the confirmation hole 49 is provided on the opposite side of the opening 45 of the guide cover 42, an air flow is formed from the opening 45 to the confirmation hole 49 through the passage 48. Therefore, when the commutator motor rotates, the heat generated by the friction between the brush 43 and the commutator 22 can be released from the confirmation hole 49 through the air flow. Therefore, a commutator motor excellent in heat dissipation is provided.

  As shown in FIGS. 4 and 5, the confirmation hole 49 has a part of the side that forms the top surface 57 of the guide cover 42 along the radial direction R on the opposite side of the opening 45 of the guide cover 42. May be formed. The guide cover 42 has a shape in which a part of the side surface 58 is cut from a part of the top surface 57.

  With this configuration, the guide cover 42 suppresses reflected light from the guide cover 42 because it does not surround the confirmation hole 49 when detecting the presence or absence of the brush spring 44 using an optical measuring instrument such as infrared rays. can do. Therefore, the detection accuracy of the presence or absence of the brush spring 44 is increased.

  Other embodiments will be described with reference to FIGS.

  FIG. 11 is a perspective explanatory view of another guide according to Embodiment 1 of the present invention. FIG. 12 is a perspective explanatory view of still another guide according to Embodiment 1 of the present invention.

  First, as another embodiment, as shown in FIG. 11, the confirmation hole 49 </ b> A is formed by a through hole located along the center line 55 of the passage 48 on the opposite side of the opening 45 of the guide cover 42. May be.

  With this configuration, the confirmation hole 49A can be efficiently formed when the guide cover 42 is created by using the following example. For example, a mold for forming the guide cover 42 has a shape for molding the confirmation hole 49A. Alternatively, when the guide cover 42 is formed by punching a metal plate or the like, the confirmation hole 49A is also punched. If these examples are used, it is not necessary to provide a special process in order to form the confirmation hole 49A. Therefore, the confirmation hole 49A is efficiently formed in the guide cover 42.

  Furthermore, as another embodiment, as shown in FIG. 12, the confirmation hole 49B may be formed in a guide 40C having a box shape. The guide 40C is formed by integrating the above-described guide cover and guide base. The guide 40C is held by the holding unit.

  The holding part in the present invention may be integrally formed with the guide as shown in the embodiment described above. Alternatively, as shown in the embodiments described later, the holding unit may be configured to hold a guide.

  At this time, the confirmation hole 49 </ b> B is located on the top surface 57 </ b> A of the guide 40 </ b> C on the center line 55 of the passage 48 on the opposite side of the opening 45.

  Even with this configuration, the same effects as those of the above-described embodiment can be achieved.

  The commutator motor in the present invention is useful for a commutator motor including an elastic member in a guide together with a brush.

DESCRIPTION OF SYMBOLS 1 Commutator motor 4 Holding part 20 Rotor 21 Rotating shaft 22 Commutator 40, 40A, 40B, 40C Guide 41, 41A, 41B Guide base 42, 42A, 42B Guide cover 43, 43A Brush 44, 44A Brush spring (elastic member)
45, 45A Opening 48 Passage 49, 49A, 49B Check hole 51 Sliding surface 55 Center line 56 Contact part R Radial

Claims (2)

A rotor having a rotating shaft and a commutator, and rotating about the rotating shaft;
A guide that forms a pair of positive and negative electrodes, has an opening at a position facing the commutator, and is opposed to the rotor along a radial direction of the rotor perpendicular to the rotation axis; ,
A brush disposed in the guide of each of the positive and negative electrodes, movable along the radial direction, and in contact with and sliding on the sliding surface with the commutator through the opening;
In each of the guides of the positive and negative electrodes, an elastic member disposed to press the brush against the commutator;
A holding part that forms the guide,
The guide is
A path through which the brush moves along the radial direction;
A commutator motor having a confirmation hole located along a center line of the passage at a position where the elastic member is disposed. The guide is
The commutator motor according to claim 1, further comprising a passage through which the brush moves and a guide cover covering the passage, wherein the guide cover has the confirmation hole.

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