JP2008245442A - Electric motor with speed reducer and noise preventing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric motor with a speed reducer and a noise preventing device, which can be reduced in the number of components and can eliminate the need for confirmation work in assembling. <P>SOLUTION: In the noise preventing device 35 of a wiper motor, a pair of power supply side connecting members 39a, 39b, wherein each one end of the connection members is connected to a motor body and each other end is connected to corresponding choke coils 37a, 37b, are formed into an identical shape, allowing the choke coils 37a, 37b to be connected to any of the power supply side connecting members 39a, 39b. This eliminates the need for separately manufacturing the power supply side connecting members 39a, 39b, enabling reduction in the number of components due to the use of commonized components. Also this eliminates the generation of assembling errors due to operation mistakes and enables, dispensing with the confirmation work at assembling. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an electric motor with a reduction gear provided with a motor body provided with a rotation shaft, and a reduction gear that decelerates and outputs the rotation of the rotation shaft, and a noise prevention device that prevents noise in an electric circuit.

  As a drive source for a wiper device, a power window device, a sunroof device or the like provided in a vehicle, an electric motor that is operated by a power source such as a battery mounted on the vehicle is usually used. In order to adapt the electric motor to these devices, it is necessary to reduce the rotational speed of the motor to a desired rotational speed. Therefore, such an electric motor is made into one unit as an electric motor with a reduction gear with a reduction gear attached.

  Usually, this electric motor with a speed reducer is housed in a housing case disposed on the speed reducer between a power supply side connection terminal connected to a power source and a power supply side connection terminal connected to the motor body, and a pair of electric motors. The elements are connected.

For example, when a motor with a brush is used as the motor body, the electric element is used to prevent other electrical components from being damaged (radio noise, etc.) due to noise generated from the sliding contact portion between the brush and the commutator. Functions as a noise prevention element. For example, in Patent Document 1, by providing the power supply side connection terminal and the power feeding side connection terminal outside the noise prevention element accommodation portion of the accommodation case, it is easy to secure the accommodation space for the noise prevention element in the accommodation case, and noise is reliably ensured. There has been proposed an anti-noise device for preventing the noise.
Japanese Patent Laid-Open No. 2000-60076

  However, in noise prevention devices used in conventional electric motors with reduction gears, the pair of power supply side connection terminals are symmetrical in plan view but are different in shape from each other. Sometimes it is necessary to check which side is used for connection to prevent work mistakes.

  An object of the present invention is to provide an electric motor with a speed reducer that can reduce the number of parts and eliminate the need for confirmation work during assembly.

  It is another object of the present invention to provide a noise prevention apparatus that can reduce the number of parts and eliminate the need for confirmation work during assembly.

  An electric motor with a speed reducer according to the present invention is an electric motor with a speed reducer comprising a motor body having a rotating shaft and a speed reducer that decelerates and outputs the rotation of the rotating shaft, on the speed reducer. A storage case disposed; a pair of electrical elements stored in the storage case; a pair of power supply side connection members each having one end connected to a power source and the other end connected to the corresponding electrical element; It is formed in the mutually same shape, It has a pair of electric power feeding side connection members each connected to the said electric element with one end connected to the said motor main body, respectively.

  In the electric motor with a reduction gear according to the present invention, the pair of power supply side connecting members each include a motor main body connecting portion connected to the motor main body and an electric element connecting portion connected to the electric element. The element connecting portion is characterized in that two grooves are provided symmetrically across the axis of the motor body connecting portion.

  The electric motor with a speed reducer according to the present invention is characterized in that the power supply side connection member and the power supply side connection member are formed by bending a plate material.

  The noise prevention device of the present invention is a noise prevention device for preventing noise in an electric circuit, and includes a housing case, a pair of noise preventing elements housed in the housing case, and one end connected to a power source, A pair of power supply side connection members whose other ends are connected to the corresponding noise prevention element are formed in the same shape as each other, and one end is connected to the electric circuit and the other end corresponds to the corresponding noise prevention element. And a pair of power supply side connection members to be connected.

  According to the present invention, the pair of power supply side connection members, each having one end connected to the motor body and the other end connected to the corresponding electrical element, are formed in the same shape as each other. It can also be connected to electrical elements. As a result, the number of parts can be reduced, and a confirmation operation can be eliminated when the power supply side connection terminal and the electric element are connected.

  According to the present invention, the pair of power supply side connecting members, each having one end connected to the electric circuit and the other end connected to the corresponding noise prevention element, are formed in the same shape as each other. It can also be connected to a noise prevention element. Thereby, it is possible to reduce the number of parts and eliminate the need for confirmation work during assembly.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a perspective view showing a wiper motor 10 according to an embodiment of the present invention, and FIG. 2 is an exploded perspective view of the wiper motor 10 shown in FIG.

  A wiper motor 10 shown in FIG. 1 is used as a drive source of a rear wiper device provided in a vehicle, and is an electric motor with a speed reducer in which a motor main body 11 and a speed reducer 12 are formed as one unit.

  The motor main body 11 shown in FIG. 2 is a motor with a brush provided with a rotating shaft 11a, and a commutator 13 (commutator) and an armature core (not shown) are fixed to the rotating shaft 11a. A plurality of coils (armature windings) (not shown) are wound around the slots of the armature core, and the ends of these coils are respectively connected to corresponding segments of the commutator. The armature (armature) is connected by the commutator 13 and the coils. 14 is configured.

  The motor body 11 includes a motor yoke (yoke) 15 formed in a cylindrical shape with a bottom having an oval cross section. The armature 14 is rotatably supported at one end of the rotating shaft 11 a on the bottom of the motor yoke 15. Thus, the motor yoke 15 is rotatably accommodated. A pair of magnets (not shown) are mounted on the inner surface of the motor yoke 15 with different magnetic poles facing each other, and the armature core around which the coil is wound is within the magnetic field formed by these magnets and the motor yoke 15. It is supposed to be located in. A brush holder 16 for holding a brush (not shown in FIG. 2) is mounted inside the motor yoke 15.

  FIG. 3 is a perspective view showing details of the brush holder 16 provided in the motor body 11. As shown in FIG. 3, the brush holder 16 is formed of a resin material, and is formed in a cylindrical shape along the inner surface of the motor yoke 15 and a main body wall portion 16a perpendicular to the axial direction of the rotating shaft 11a. And an outer peripheral wall portion 16b that covers the outer periphery of the motor yoke 15. The outer peripheral wall portion 16b is mounted inside the motor yoke 15 so as to be in sliding contact with the inner surface of the motor yoke 15. Further, a through hole 16c is formed in the axis of the main body wall portion 16a. When the brush holder 16 is mounted on the motor yoke 15, the commutator 13 of the armature 14 is inserted into the through hole 16c and the main body wall portion 16a. It is arranged inside.

  A pair of brushes 17 (one not shown) held by the brush holder 16 is fixed to one end of a pair of leaf springs 18a and 18b which are bent in a U-shape, respectively. The other end is fixed to the brush holder 16 by a fastening member (bolt) 19 so that the brush 17 is in sliding contact with the outer peripheral surface of the commutator 13 while being urged by the leaf springs 18a and 18b. The leaf springs 18a and 18b are formed of a metal plate such as a copper plate. When a direct current is supplied to the leaf springs 18a and 18b, the current is supplied to the brush 17 via the leaf springs 18a and 18b. It has become. When a current is supplied to each brush 17, the current is commutated by the commutator 13 and supplied to each coil, thereby energizing the coil in the magnetic field and rotating the rotating shaft 11 a together with the armature 14. become.

The brush holder 16 is provided with a motor yoke side ground terminal 45 for grounding the negative brush 17 to the motor yoke 15. The motor yoke side ground terminal 45 is formed by bending a metal plate such as a copper plate, and is fixed to the main body wall portion 16a of the brush holder 16 at the main body portion 45a, and the terminal portion 45b is bent with respect to the main body portion 45a. And protrudes outside the outer peripheral wall portion 16b. Further, the main body 45 a of the motor yoke side ground terminal 45 is connected to the negative brush 17 through a wiring board provided in the brush holder 16.

  When the brush holder 16 is mounted inside the motor yoke 15, the terminal portion 45 b of the motor yoke-side ground terminal 45 comes into contact with the inner surface of the motor yoke 15 in an elastically deformed state, thereby being grounded to the motor yoke 15. When the negative-side brush 17 is grounded to the motor yoke 15, the motor yoke 15 has a shielding effect, and noise can be prevented from being radiated to the outside of the motor via the motor yoke 15.

  On the other hand, the speed reducer 12 has a gear case 20 fixed to the motor yoke 15. The gear case 20 is formed of a conductor such as an aluminum alloy, and is electrically connected to the motor yoke 15 when fixed to the motor yoke 15.

  FIG. 4 is a partially cutaway sectional view showing the internal structure of the speed reducer 12 shown in FIG. As shown in FIG. 4, a reduction mechanism 21 is accommodated in the gear case 20. The speed reduction mechanism 21 is a worm gear mechanism that includes a worm 22 and a worm wheel 23 that meshes with the worm 22. The worm 22 is integrally formed on the outer peripheral surface of the rotating shaft 11 a that protrudes into the gear case 20. Is supported by a support shaft 24 provided in the gear case 20 and is rotatable within the gear case 20. Therefore, when the motor body 11 is operated to rotate the rotating shaft 11 a, the rotation is reduced to a predetermined number of rotations by the reduction mechanism 21 and transmitted to the worm wheel 23.

  Further, the speed reducer 12 is provided with a power conversion mechanism 26 for converting the rotation of the worm wheel 23 into a swinging motion and transmitting it to the output shaft 25. The power conversion mechanism 26 includes a power conversion member 27 and an output gear 28, and the power conversion member 27 includes an arm portion 27 a and a sector gear portion 27 b, and the distal end portion of the arm portion 27 a is warmed by a connecting shaft 29. The wheel 23 is rotatably connected to a position away from the rotation center axis of the wheel 23. On the other hand, the output gear 28 is fixed to the base end portion of the output shaft 25 protruding into the gear case 20 and meshed with the sector gear portion 27 b of the power conversion member 27. A gear shaft 30 is provided at the axis of the sector gear portion 27b, and the gear shaft 30 and the output shaft 25 are slidably connected by a plate member 31, whereby the sector gear portion 27b is connected to the output gear 28. Are held in a state of being engaged with each other.

  With such a structure, when the motor body 11 is operated and the worm wheel 23 is rotated, the arm portion 27a is reciprocated by the rotation, and the sector gear portion 27b is oscillated with respect to the output gear 28. Is rotated into a swinging motion and output from the output shaft 25. That is, in the wiper motor 10, the rotational motion of the rotating shaft 11 a that is the power of the motor body 11 is decelerated by the speed reduction mechanism 21, converted into a swinging motion by the power conversion mechanism 26, and output from the output shaft 25. Yes.

  As shown in FIG. 1, the gear case 20 is formed with a boss portion 20 a that protrudes in parallel with the support shaft 24, and the output shaft 25 is rotatably supported by the boss portion 20 a in parallel with the support shaft 24. Yes. The distal end of the output shaft 25 protrudes outside from the boss portion 20a, and a rear wiper arm constituting the rear wiper device is attached to the distal end. Thus, when the motor body 11 is operated, the rear wiper arm swings together with the output shaft 25, and the wiping operation by the rear wiper device is performed.

  The wiper motor 10 is provided with a connector 32 formed as an independent unit as shown in FIGS. 1 and 4 for connection to a power source such as a battery (not shown) or a wiper switch. The connector 32 is disposed on the outer surface of the gear case 20 and is fixed to the gear case 20 by fastening members (bolts) 33. The connector 32 is provided with a pair of power supply terminals 34a and 34b. The power supply terminal 34a is connected to a power source and a wiper switch via wiring, and the power supply terminal 34b is connected to an external connector on the vehicle body side (not shown). To be grounded. When the wiper switch is turned on, power is supplied from the power source to one power supply terminal 34a.

  As shown in FIGS. 1 and 2, a noise prevention device 35 is disposed on the outer surface of the gear case 20 on the speed reducer 12. FIG. 5A is a perspective view showing the main part of the noise prevention device 35 shown in FIG. 1, and FIG. 5B is a plan view showing the main part of the noise prevention device 35 shown in FIG.

  As shown in FIGS. 3 and 5, the noise prevention device 35 includes a housing case 36, choke coils 37 a and 37 b as a pair of noise preventing elements (electric elements) housed in the housing case, and a housing case 36. It has a pair of power supply side connection members 38a and 38b fixed to the end part on the connector 32 side, and a pair of power supply side connection members 39a and 39b fixed to the end part on the brush holder 16 side of the housing case 36. Yes.

  As shown in FIG. 3, the housing case 36 is formed in a vertically long bathtub shape from a resin material, and is fixed to the brush holder 16 at one end thereof along the outer peripheral wall portion 16 b. That is, the storage case 36 is fixed to the brush holder 16 and is provided integrally with the brush holder 16. When the brush holder 16 is attached to the motor yoke 15, the storage case 36 is opened from the inside of the motor yoke 15. It protrudes to the gear case 20 side via. When the gear case 20 is fixed to the motor yoke 15, the housing case 36 is arranged on the outer surface of the gear case 20. Note that the illustrated housing case 36 shows a state in which the lid is removed.

  The pair of choke coils 37a and 37b is housed in the housing case 36 together with a bidirectional varistor 43 having a function of a capacitor as a capacitive element and a varistor. That is, the storage case 36 is provided with a partition wall 44 that divides the storage case 36 into three spaces. The choke coils 37a and 37b are arranged side by side in the storage case 36 and separated from each other by the partition wall 44. The bidirectional varistor 43 is housed side by side on the connector 32 side with respect to the respective choke coils 37a and 37b and is separated from the respective choke coils 37a and 37b by a partition wall 44. The spaces defined by the partition walls 44 are set to shapes and sizes corresponding to the outer shapes of the choke coils 37a and 37b and the bidirectional varistor 43, and the choke coils 37a and 37b and the bidirectional varistor 43 are provided in each space. It can be easily installed. As the capacitive element, only a capacitor or a varistor may be mounted.

  Each of the pair of power supply side connection members 38a and 38b is formed by bending a metal plate such as a copper plate, and one end thereof is electrically connected to the power supply via the corresponding power supply terminals 34a and 34b of the connector 32. The ends protrude in parallel with the interior of the housing case 36. The power supply side connection member 38b on the negative electrode side is provided with a gear case side ground terminal 46 for grounding the power supply side connection member 38b to the gear case 20. The gear case side ground terminal 46 is formed by bending a part of the power supply side connection member 38b protruding from the housing case 36 toward the connector 32 into a V shape so as to be folded back toward the housing case 36. It can be elastically deformed in a direction approaching and separating from a certain power supply side connection member 38b.

  That is, since the gear case side ground terminal 46 is grounded to the gear case 20 on the power supply terminals 34 a and 34 b side and the gear case 20 is electrically connected to the motor yoke 15, the noise that could not be absorbed by the noise prevention device 35. Is returned to the inside of the motor main body 11 through the gear case 20 and the motor yoke 15, so that noise radiated to the outside of the motor can be reduced.

  Further, by bending a part of the power supply side connection member 38b into a V shape to form the gear case side ground terminal 46, it is possible to secure a sufficient deflection length for the gear case side ground terminal 46 even in a narrow space. The gear case side ground terminal 46 can be reliably grounded to the gear case 20 without using a fastening member such as a screw. Thereby, a number of parts, an assembly man-hour, etc. can be reduced.

  The pair of power supply side connection members 39a and 39b is formed by bending a metal plate such as a copper plate, and includes motor body connection portions 40a and 40b and electric element connection portions 41a and 41b. One end of each of the motor body connecting portions 40a and 40b is connected to the corresponding leaf springs 18a and 18b of the corresponding brush 17 via a wiring board provided on the brush holder 16 of the motor body 11 (electric circuit), and the other end is connected to the motor yoke. It protrudes in parallel with the inside of the housing case 36 through the 15 openings. The electric element connecting portions 41a and 41b are provided on the other end of the corresponding motor main body connecting portions 40a and 40b symmetrically in a plan view in a direction orthogonal to the axis of the motor main body connecting portions 40a and 40b. The electric element connecting portion 41a is provided with a pair of grooves 42a and 42b, and the electric element connecting portion 41b is also provided with a pair of grooves 42c and 42d symmetrically. That is, the power supply side connection members 39a and 39b are formed in the same shape.

  The choke coil 37a has one end connected to the power supply side connection member 38a as shown in FIG. 3 and the other end inserted into the groove 42a as shown in FIGS. 3 and 5, thereby supplying the power supply side connection member 39a. Connected with. Similarly, the choke coil 37b has one end connected to the power supply side connection member 38b and the other end connected to the power supply side connection member 39b by being inserted into the groove 42d. That is, the pair of choke coils 37a and 37b are connected in series between the corresponding power supply side connection members 38a and 38b and the power supply side connection members 39a and 39b. The bidirectional varistor 43 is electrically connected to the choke coils 37a and 37b by having one end connected to the power supply side connection member 38a and the other end connected to the power supply side connection member 38b.

  Thus, in the noise prevention device 35, the power supply side connection members 39a and 39b are formed in the same shape, and the power supply side connection member 39a is provided with a pair of grooves 42a and 42b symmetrically in plan view, and the power supply side connection member 39a. Similarly, since the pair of grooves 42c and 42d are provided, the choke coils 37a and 37b can be connected to any of the power supply side connection members 39a and 39b.

  FIG. 6 is a plan view showing a main part of the noise prevention device 35 using power supply side connection members 39a and 39b that are symmetrical in plan view but are not the same shape. In the power supply side connection members 39a and 39b shown in FIG. 6, only the grooves 42a and 42d are provided in the electrical element connection portions 41a and 41b, and the grooves 42b and 42c are not provided. When the power supply side connection members 39a and 39b are not symmetrical but have the same shape as each of the power supply side connection members 39a and 39b and each has only one groove, the power supply side connection member 39a is used for connecting the choke coil 37a. The connection member 39b can only be used for connecting the choke coil 37b, and it is necessary to manufacture the power supply side connection members 39a and 39b separately. Further, if it is not confirmed which side is to be connected at the time of assembly, the power feeding side connection members 39a and 39b may be disposed in reverse, and the choke coils 37a and 37b may not be connected.

  On the other hand, when two grooves are provided on the power supply side connection members 39a and 39b as described above and formed in the same shape, it is not necessary to separately manufacture the power supply side connection members 39a and 39b. It becomes possible to reduce the number of members by sharing the members. In addition, work mistakes due to wrong assembly are not caused, and it is possible to eliminate the need for confirmation work during assembly.

  In the noise prevention device 35, if the choke coils 37a and 37b are respectively inserted into the grooves 42a and 42d provided in the electric element connection portions 41a and 41b of the corresponding power supply side connection members 39a and 39b, the power supply side connection is established. Since the members 39a and 39b can be connected, the work of assembling the choke coils 37a and 37b to the power supply side connection members 39a and 39b can be facilitated.

  Further, in the noise prevention device 35, the power supply side connection members 38a and 38b and the power supply side connection members 39a and 39b are formed by bending a metal plate, and therefore can be easily manufactured.

  Further, in the wiper motor 10 having the noise prevention device 35, even if noise is generated from the sliding contact portion between the brush 17 and the commutator 13, the noise is absorbed by the choke coils 37a and 37b and the bidirectional varistor 43, Noise emission to the outside of the motor can be reduced. Since the noise prevention device 35 is provided immediately after the opening of the motor yoke 15, the noise radiated from the inside of the motor yoke 15 to the outside through this opening is propagated to other wirings and the like. By removing the noise with the noise prevention device 35 in advance, the emission of noise to the outside of the motor can be reduced.

  The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention. For example, in the present embodiment, the case where the noise prevention device 35 is applied to the wiper motor 10 that drives the rear wiper arm of the vehicle is shown, but the present invention is not limited to this, and for example, a power window device or a sunroof device for vehicles. The present invention may be applied to a motor or the like used as a drive source such as, or may be applied to an electric circuit other than the motor.

  In the present embodiment, the wiper motor 10 is a brush motor, but may be a brushless motor.

  Furthermore, in the present embodiment, the noise prevention device 35 includes choke coils 37a and 37b as noise prevention elements, but elements other than the choke coils 37a and 37b may be used as noise prevention elements. Instead of the choke coils 37a and 37b, a simple electric element made of a linear wire or the like may be used.

  Further, in the present embodiment, from the viewpoint of facilitating the assembly of the choke coils 37a and 37b, the power supply side connection members 39a and 39b are provided with grooves 42a to 42d in the electric element connection portions 41a and 41b, and the grooves 42a, The choke coils 37a and 37b corresponding to 42d are inserted, but the choke coils 37a and 37b can be connected to any one of the power supply side connection members 39a and 39b. For example, the grooves 42a to 42d may not be provided.

  Furthermore, in the present embodiment, the power supply side connection members 38a and 38b and the power supply side connection members 39a and 39b are formed by bending a metal plate. However, a plate material other than the metal plate may be used, or the bending may be performed. Instead, it may be simply a linear shape.

It is a perspective view which shows the wiper motor which is one embodiment of this invention. It is a disassembled perspective view of the wiper motor shown in FIG. It is a perspective view which shows the detail of the brush holder provided in a motor main body. FIG. 2 is a partially cutaway cross-sectional view showing an internal structure of the reduction gear shown in FIG. 1. (A) is a perspective view which shows the principal part of the noise prevention apparatus shown in FIG. 1, (b) is a top view which shows the principal part of the noise prevention apparatus shown in FIG. It is a top view which shows the principal part of the noise prevention apparatus using the electric power feeding side connection member which is left-right symmetric by planar view but is not the same shape.

Explanation of symbols

10 Wiper motor (electric motor with reduction gear)
11 Motor body (electric circuit)
11a Rotating shaft 12 Reducer 35 Noise prevention device 36 Housing case 37a, 37b Choke coil (electric element)
38a, 38b Power supply side connection members 39a, 39b Power supply side connection members 40a, 40b Motor body connection portions 41a, 41b Electric element connection portions 42a-d Grooves

Claims (4)

An electric motor with a speed reducer comprising a motor body having a rotating shaft and a speed reducer that decelerates and outputs the rotation of the rotating shaft,
A storage case disposed on the speed reducer;
A pair of electrical elements housed in the housing case;
A pair of power supply side connection members each having one end connected to a power source and the other end connected to the corresponding electrical element;
An electric motor with a speed reducer, which is formed in the same shape as each other, and has a pair of power supply side connection members each having one end connected to the motor body and the other end connected to the corresponding electric element. . An electric motor with a reduction gear according to claim 1,
The pair of power supply side connection members each include a motor main body connection portion connected to the motor main body and an electric element connection portion connected to the electric element,
2. The electric motor with a speed reducer, wherein the electric element connecting portion is provided with two grooves symmetrically across the axis of the motor main body connecting portion. An electric motor with a speed reducer according to claim 1 or 2,
The power supply side connecting member and the power feeding side connecting member are formed by bending a plate material. An anti-noise device for preventing noise in an electric circuit,
A containment case;
A pair of noise preventing elements housed in the housing case;
A pair of power supply side connection members each having one end connected to a power source and the other end connected to the corresponding noise prevention element,
A noise prevention apparatus, comprising: a pair of power supply side connection members formed in the same shape and having one end connected to the electric circuit and the other end connected to the corresponding noise prevention element.

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