JP2009293643A - Electric motor with speed reduction mechanism - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce noise when an electric motor with a reduction mechanism is operated. <P>SOLUTION: The electric motor 31 with the reduction mechanism is provided with a worm gear mechanism 46 for decelerating the rotation of an armature shaft 44a provided in the electric motor 31 and transmitting the rotation to an output shaft 35 and with an electromagnetic clutch 51 for connecting/disconnecting power transmission between the armature shaft 44a and the output shaft 35. A worm wheel 48 constituting the worm gear mechanism 46 and a clutch rotor 52 constituting the electromagnetic clutch 51 are fitted to the output shaft 35 relatively rotatably, and are interconnected by a rotor ring 58 so as to enable power transmission. A wave washer 81 is fitted to the output shaft 35, and by the wave washer 81, the worm wheel 48 is axially energized toward the side of the clutch rotor 52. The worm wheel 48 and the rotor ring 58 are supported by the clutch rotor 52, so as to absorb looseness in the axial direction. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an electric motor with a speed reduction mechanism that is used as, for example, a drive source of an automatic opening / closing device that automatically opens and closes a sliding door provided in a vehicle.

  2. Description of the Related Art Conventionally, as a drive source for a slide door automatic opening / closing device that automatically opens and closes a vehicle slide door, an electric motor with a speed reduction mechanism capable of obtaining a desired driving force from a small electric motor (motor body) has been used. It has been. In such an electric motor with a speed reduction mechanism, a worm gear mechanism that is small and can provide a large reduction ratio is often used as the speed reduction mechanism. In this case, the worm is provided integrally with the rotating shaft (an amateur shaft) of the electric motor. The worm wheel that meshes with is attached to the output shaft.

  On the other hand, in an electric motor with a speed reduction mechanism used in a slide door automatic opening / closing device, a clutch mechanism (electromagnetic clutch) is provided inside a gear case that houses the speed reduction mechanism. The clutch mechanism cuts off power transmission between the rotating shaft and the output shaft to reduce manual operation force.

For example, in Patent Document 1, a worm wheel and a clutch rotor (first clutch plate) are attached to an output shaft so as to be relatively rotatable, and these are connected to each other by a cylindrical rotor ring (power transmission member). The armature (second clutch plate) is mounted so as to be movable in the axial direction between an engagement position capable of transmitting power to the output shaft and engaging with the clutch rotor and a release position where the engagement is released. An electric motor with a speed reduction mechanism with a clutch mechanism is described in which an armature and a clutch rotor are intermittently operated by a clutch coil opposed to the armature across the armature.
JP 2007-327605 A

  However, in the electric motor with a speed reduction mechanism disclosed in Patent Document 1, the worm wheel and the rotor ring are mounted on the output shaft so as to be relatively rotatable, and the structure has a slight clearance (backlash) in the axial direction. When the motor is operated, it may move in the axial direction due to the load from the worm, and may cause abnormal noise due to collision with other peripheral members.

  An object of the present invention is to reduce noise during operation of an electric motor with a speed reduction mechanism.

  An electric motor with a speed reduction mechanism of the present invention includes a motor body having a rotation shaft, a speed reduction mechanism that decelerates rotation of the rotation shaft and outputs it from an output shaft, and transmits power between the rotation shaft and the output shaft. An electric motor with a speed reduction mechanism including an intermittent clutch mechanism, wherein the speed reduction mechanism is mounted by a worm that rotates together with the rotary shaft, and is rotatably attached to the output shaft, and meshes with the worm and the worm. , A first clutch plate that is provided with a first engagement portion on an axial end face, and is rotatably mounted on the output shaft, and is disposed coaxially with the output shaft, and is axially A power transmission member connected to the worm wheel on one side and connected to the outer peripheral edge of the first clutch plate on the other side, and a second engagement facing the first engagement portion And is connected to the output shaft so as to be able to transmit power, and is movable in an axial direction between an engagement position for engaging with the first clutch plate and a release position for releasing the engagement. A second clutch plate that constitutes the clutch mechanism with the first clutch plate; and an urging means that is attached to the output shaft and urges the worm wheel toward the first clutch plate. It is characterized by having.

  In the electric motor with a speed reduction mechanism according to the present invention, the power transmission member is axially oriented from a disc portion facing an end surface in the axial direction of the worm wheel facing the first clutch plate and an outer peripheral edge of the disc portion. A cylindrical portion that extends to the axial end surface of the worm wheel at the disc portion, and is connected to an outer peripheral edge portion of the first clutch plate at the cylindrical portion, and the attachment portion via the worm wheel. It is biased toward the first clutch plate by the biasing means.

  An electric motor with a speed reduction mechanism according to the present invention includes an annular detected body fixed to the output shaft, and a rotation sensor disposed inside a case that houses the speed reduction mechanism and facing the detected body, The urging means is arranged between the detected object and the worm wheel.

  In the electric motor with a speed reduction mechanism according to the present invention, the detected object is formed in an annular shape in which a plurality of magnetic poles are aligned in the circumferential direction and a disk-shaped sensor plate fixed to the output shaft. A sensor magnet fixed outward in the direction, and the urging means is disposed between the sensor plate and the worm wheel.

  The electric motor with a speed reduction mechanism according to the present invention is characterized in that the urging means is a wave washer.

  According to the present invention, since the worm wheel is urged toward the first clutch plate by the urging means attached to the output shaft, the worm wheel is supported by the first clutch and the axial direction of the worm wheel is supported. Can absorb backlash. As a result, it is possible to prevent abnormal noise caused by the worm wheel moving in the axial direction when the motor is operated.

  Further, according to the present invention, the power transmission member is formed in a shape including a disk part facing the axial end surface of the worm wheel and a cylindrical part extending in the axial direction from the outer peripheral edge of the disk part, and the disk part In this embodiment, the worm wheel is connected to the axial end surface of the worm wheel and biased toward the first clutch plate by the biasing means via the worm wheel. The backlash of the engagement and the backlash of the engagement between the power transmission member and the first clutch plate can be reduced at the same time, and the connection strength can be increased. As a result, the worm wheel can be formed of an inexpensive material, and the cost of the electric motor with a speed reduction mechanism can be reduced.

  Further, according to the present invention, the detected body is fixed to the output shaft and the urging means is disposed between the detected body and the worm wheel. Thus, the elastic force can be effectively transmitted to the power transmission member.

  In addition, according to the present invention, the object to be detected is composed of a disk-shaped sensor plate fixed to the output shaft and a sensor magnet fixed to the outside in the radial direction of the sensor plate, and the urging means is the sensor plate and the worm wheel. Therefore, it is possible to prevent the elastic force of the urging means from affecting the sensor magnet portion of the detection object.

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

  FIG. 1 is a side view of a one-box type vehicle, and a sliding door 13 is provided on the side of a vehicle body 12 of the vehicle 11.

  FIG. 2 is a plan view showing a structure for mounting the slide door shown in FIG. 1 to the vehicle body. A guide rail 14 is fixed to a side portion of the vehicle body 12, while a roller assembly 15 is attached to the slide door 13. When the roller assembly 15 is movably mounted on the guide rail 14 and guided along the guide rail 14, the slide door 13 is shown along the side of the vehicle body 12 by a solid line in FIG. It can be freely opened and closed between a fully closed position shown and a fully open position shown by a two-dot chain line. Further, a pull-in portion 14a that bends toward the vehicle interior side is provided on the vehicle front side of the guide rail 14, and the roller assembly 15 is guided along the pull-in portion 14a, so that the slide door 13 is connected to the side surface of the vehicle body 12. It is closed in a state where it is drawn inside the vehicle body 12 so as to fit in the same plane.

  Although not shown, the roller assembly 15 is also provided in the upper and lower portions (upper portion and lower portion) of the front end portion of the slide door 13 in addition to the portion (center portion) shown in the drawing, and the opening of the vehicle body 12 corresponding to these is provided. Guide rails 14 corresponding to the upper and lower portions are also provided at the upper and lower edge portions, and the sliding doors 13 are supported by the vehicle body 12 at a total of three locations so as to be freely opened and closed.

  The vehicle 11 is provided with a slide door automatic opening / closing device 21 (hereinafter referred to as an opening / closing device 21) in order to automatically open and close the slide door 13.

  The opening / closing device 21 is a so-called cable type, and a drive unit 22 disposed in the interior of the vehicle body 12 adjacent to a substantially central portion of the guide rail 14 in the vehicle front-rear direction, and a slide door 13 A closed side cable 23a and an open side cable 23b. The closed cable 23a is guided to the roller assembly 15 from the closed side (vehicle front side) via a reversing pulley 24a provided at the end of the guide rail 14 on the vehicle front side. It is connected to the door 13). The open side cable 23b is led to the roller assembly 15 from the open side (rear side of the vehicle) via a reversing pulley 24b provided at the end of the guide rail 14 on the rear side of the vehicle. It is connected to the door 13). The other ends of the cables 23 a and 23 b are connected to the drive unit 22. When the closed cable 23 a is pulled by the drive unit 22, the slide door 13 is pulled by the cable 23 a and automatically opens. Thus, when the open side cable 23b is pulled, the slide door 13 is pulled by the cable 23b and automatically closes.

  3 is a front view showing details of the drive unit shown in FIG. 2, and FIG. 4 is a cross-sectional view taken along the line AA of the drive unit shown in FIG.

  As shown in FIGS. 3 and 4, the drive unit 22 has a structure in which an electric motor 31 with a speed reduction mechanism and a cable drive mechanism 32 are formed as one unit, and a resin case 33 commonly used for these units. The case 33 is fixed to the vehicle body 12.

  The case 33 is provided with a substantially cylindrical drum accommodating chamber 33a, and a driving drum 34 is accommodated in the drum accommodating chamber 33a. The drive drum 34 is formed in a columnar shape having a spiral guide groove 34a on the outer periphery, and the closed side cable 23a and the open side cable 23b led to the drive unit 22 are the same in the guide groove 34a. It is wound in the direction. Further, the output shaft 35 of the electric motor 31 with a speed reduction mechanism is rotatably supported by the case 33 by a pair of ball bearings 36a and 36b, one end of which protrudes into the drum accommodating chamber 33a, and the driving drum 34 is The shaft is fixed to the tip of the output shaft 35 with a nut 37.

  The case 33 is provided with a tensioner storage chamber 33b adjacent to the drum storage chamber 33a. The closed side cable 23a and the open side cable 23b guided to the drive unit 22 are respectively connected to the cable entry / exit portion 33c provided in the case 33. , 33d are drawn into the tensioner accommodating chamber 33b and guided to the drum accommodating chamber 33a via the tensioner accommodating chamber 33b. The tensioner accommodating chamber 33b accommodates a closed tensioner pulley 38a over which the closed cable 23a is spanned and an open tensioner pulley 38b over which the open cable 23b is spanned. These tensioner pulleys 38a and 38b are rotatably supported by holders 39a and 39b, respectively. These holders 39a and 39b are supported by guide shafts 40a and 40b supported by the case 33 so as to be linearly reciprocable and guide shafts. The springs 41a and 41b attached to the 40a and 40b are biased toward the direction in which the movement paths of the corresponding cables 23a and 23b are increased. As a result, the cables 23a and 23b are urged by the corresponding tensioner pulleys 38a and 38b to be applied with a predetermined tension, and the cable assembly 23a and the cable 23a and the cable 23a are guided by the pull-in portion 14a of the guide rail 14 and the like. Even if the movement path length of 23b changes, the tension is kept constant.

  The case 33 and the reversing pulleys 24a and 24b are connected by flexible outer tubes 42a and 42b, and the cables 23a and 24b are connected between the case 33 and the reversing pulleys 24a and 24b. 23b is inserted in the outer tubes 42a and 42b and moves along the outer tubes 42a and 42b. As shown in FIG. 4, the drum storage chamber 33 a and the tensioner storage chamber 33 b are closed by a cover 43 attached to the case 33.

  The electric motor 31 with a speed reduction mechanism is provided with an electric motor 44 as a motor body in order to rotate and drive the driving drum 34 to automatically open and close the slide door 13. The electric motor 44 is attached to the case 33, and an armature shaft 44 a serving as a rotation shaft projects into the gear housing chamber 33 e provided in the case 33.

  In addition, as the electric motor 44, for example, a DC motor with a brush such that the armature shaft 44a can rotate in both forward and reverse directions is used. As shown in FIG. 4, the gear housing chamber 33 e is closed by a cover 45 attached to the case 33.

  In order to decelerate the rotation of the armature shaft 44a and transmit it to the output shaft 35, a gear housing chamber 33e of the case 33 accommodates a worm gear mechanism 46 as a speed reducing mechanism. The worm gear mechanism 46 includes a worm 47 that is integrally provided on an outer peripheral surface of a portion of the armature shaft 44 a that protrudes into the gear housing chamber 33 e and rotates together with the armature shaft 44 a, and a worm wheel 48 that meshes with the worm 47. The worm wheel 48 is attached to the output shaft 35 so as to be rotatable relative to the output shaft 35 at the shaft center thereof, and is rotatable within the gear housing chamber 33e.

  Further, in order to intermittently connect the power transmission path between the armature shaft 44a and the output shaft 35, the gear receiving chamber 33e of the case 33 is adjacent to the worm gear mechanism 46 in the axial direction, and an electromagnetic clutch 51 as a clutch mechanism. Is housed. The electromagnetic clutch 51 is a so-called friction type, and includes a clutch rotor 52 as a first clutch plate and an armature 53 as a second clutch plate.

  The clutch rotor 52 is formed of a steel material in an annular shape having a substantially U-shaped cross section, and a friction surface 52a serving as a first engagement portion is formed on an end surface in the axial direction facing the worm wheel 48 side. A boss portion 52b is provided at the shaft center of the clutch rotor 52, and the clutch rotor 52 is attached to the output shaft 35 by a sliding bearing 54 at the boss portion 52b so as to be relatively rotatable. The sliding bearing 54 that supports the boss portion 52b of the clutch rotor 52 is formed in an annular shape having a substantially U-shaped cross section, and is fitted and fixed to the output shaft 35. The clutch rotor 52 has a U-shaped configuration. Arranged inside, the movement in the axial direction relative to the output shaft 35 is restricted.

  On the other hand, the armature 53 is formed of a steel material in an annular shape having substantially the same diameter as that of the clutch rotor 52 having a through-hole in the shaft center, and is disposed between the worm wheel 48 and the clutch rotor 52 coaxially therewith. A friction surface 53 a as a second engaging portion that faces the friction surface 52 a of the clutch rotor 52 is formed on the end surface in the axial direction of the armature 53 facing the clutch rotor 52, and this friction surface 53 a is formed in the clutch rotor 52. It faces the friction surface 52a with a slight gap. A connecting member 55 fitted and fixed to the output shaft 35 is disposed inside a through hole formed in the axial center of the armature 53. The connecting member 55 and the armature 53 are connected by a leaf spring 56. Yes. The plate spring 56 is formed in a disk shape by punching a steel plate into a predetermined shape, and is elastically deformable in the axial direction and has a predetermined rigidity in the circumferential direction. As a result, the armature 53 is connected to the output shaft 35 through the leaf spring 56 and the connecting member 55 so that power can be transmitted, that is, to rotate together with the output shaft 35, and the armature 53 is elastically deformed in the axial direction of the leaf spring 56. The friction surface 53a is axially movable between an engagement position where the friction surface 53a is engaged with the friction surface 52a of the clutch rotor 52 and a release position where the friction surface 53a is separated from the friction surface 52a of the clutch rotor 52 and the engagement is released. Yes. The leaf spring 56 is in a natural state where it is not elastically deformed when the armature 53 is in the release position, and is elastically deformed in the axial direction when the armature 53 is moved to the engaging position.

  In the gear housing chamber 33e of the case 33, a clutch coil 57 is provided adjacent to the back side of the clutch rotor 52, that is, the side opposite to the armature 53 of the clutch rotor 52, and the clutch coil 57 is energized. The armature 53 is moved from the release position to the engagement position by the magnetic attractive force generated by the clutch coil 57, and the electromagnetic clutch 51 is switched to the power transmission state. When the energization of the clutch coil 57 is released, the armature 53 is moved from the engagement position to the release position by the spring force of the leaf spring 56, and the electromagnetic clutch 51 is switched to the power cut-off state.

  In order to transmit power between the worm wheel 48 and the clutch rotor 52, the electromagnetic clutch 51 is provided with a rotor ring 58 as a power transmission member.

  FIGS. 5A and 5B are exploded perspective views for explaining a connecting structure of the rotor ring to the worm wheel and the clutch rotor, respectively.

  In the rotor ring 58, a disc-shaped disc portion 59 having a through hole 59a in the shaft center and a cylindrical cylindrical portion 61 extending in the axial direction from the outer peripheral edge of the disc portion 59 are integrated by a resin material or the like. And the disc portion 59 is opposed to the axial end surface of the worm wheel 48 facing the clutch rotor 52 side, and the shaft 61 of the cylinder portion 61 is opposite to the disc portion 59. Between the worm wheel 48 and the clutch rotor 52, the directional end portion is arranged coaxially with the output shaft 35 between the worm wheel 48 and the clutch rotor 52.

  As shown in FIG. 5A, a connecting recess 62 is provided on the end face in the axial direction of the worm wheel 48 facing the clutch rotor 52, that is, the rotor ring 58. The connecting recess 62 has a circular shape centered on the shaft center and is formed in a concave shape that is recessed in the axial direction toward the opposite side of the rotor ring 58, and a plurality of connecting teeth are circumferentially provided on the inner peripheral surface thereof. The recess side teeth 62a are provided by being arranged at equal intervals. Correspondingly, as shown in FIG. 5B, a connecting convex portion 63 is provided on the end surface in the axial direction of the disc portion 59 of the rotor ring 58 facing the worm wheel 48 side. This connection convex part 63 is formed in the column shape which protrudes in the axial direction toward the worm wheel 48 side centering on an axial center, and several connection teeth are arranged in the circumferential direction at equal intervals on the outer peripheral surface. Thus, the convex side teeth 63a are provided. The recess-side teeth 62a of the connection recess 62 and the protrusion-side teeth 63a of the connection projection 63 are formed at the same pitch, and the connection projection 63 of the rotor ring 58 is pivoted inside the connection recess 62 of the worm wheel 48. When the worm wheel 48 and the rotor ring 58 are combined from the axial direction so as to be inserted from the direction, the concave portion side tooth portion 62a and the convex portion side tooth portion 63a are engaged, and the worm wheel 48 and the rotor ring 58 are engaged. Are connected so that power can be transmitted.

  On the other hand, as shown in FIG. 5A, the inner circumferential surface of the cylindrical portion 61 of the rotor ring 58 extends along the axial direction from the axial front end portion on the clutch rotor 52 side toward the worm wheel 48 side. A plurality of connecting grooves 61a extending at a predetermined length are provided at equal intervals in the circumferential direction. Further, as shown in FIGS. 5A and 5B, a plurality of connection projections 52 c are formed on the outer peripheral surface of the clutch rotor 52 so as to be arranged at equal intervals in the circumferential direction. The connecting groove 61a of the rotor ring 58 and the connecting protrusion 52c of the clutch rotor 52 are formed at the same pitch, and when the rotor ring 58 and the clutch rotor 52 are combined in the axial direction, the connecting groove 61a of the rotor ring 58 is engaged with the clutch. The connection protrusion 52c of the rotor 52 is engaged, and the rotor ring 58 and the clutch rotor 52 are connected so as to be able to transmit power.

  In other words, the rotor ring 58 is connected to the axial end surface of the worm wheel 48 at the disk portion 59 provided on one side in the axial direction so that power can be transmitted, and the clutch is provided at the cylindrical portion 61 provided on the other side in the axial direction. It is connected to the outer peripheral edge of the rotor 52 so as to be able to transmit power, so that power is transmitted between the worm wheel 48 and the clutch rotor 52.

  As described above, in the electric motor 31 with the speed reduction mechanism, the rotor ring 58 includes the disc portion 59 facing the axial end surface of the worm wheel 48 and the cylindrical portion 61 extending in the axial direction from the outer peripheral edge of the disc portion 59. Since it is formed in a cylindrical shape with a bottom and is connected to the axial end surface of the worm wheel 48 at the disk portion 59, the strength of the connection structure between the worm wheel 48 and the rotor ring 58 can be increased. As a result, the worm wheel 48 can be formed of an inexpensive material without using an expensive material having high strength, and the cost of the electric motor 31 with a speed reduction mechanism can be reduced. In addition, since it is easy to ensure the strength of the worm wheel 48, the thickness of the worm wheel 48 in the axial direction can be reduced, and the electric motor 31 with a speed reduction mechanism can be downsized.

  Furthermore, in this electric motor 31 with a speed reduction mechanism, the worm wheel is obtained by combining the connecting concave portion 62 formed on the axial end surface of the worm wheel 48 and the connecting convex portion 63 formed on the axial end surface of the rotor ring 58 in the axial direction. Since 48 and the rotor ring 58 are connected, the strength of the connection structure between the worm wheel 48 and the rotor ring 58 can be further increased.

  As shown in FIG. 4, a substrate housing chamber 33f is provided on the back side of the tensioner housing chamber 33b of the case 33, and this substrate housing chamber 33f is for controlling the operation of the electric motor 44 and the electromagnetic clutch 51. A control board 64 is accommodated. The control board 64 has a structure in which electronic components such as a CPU and a memory are mounted on the board. A power source such as a battery (not shown) mounted on the vehicle 11 via a connection connector 65 provided on the case 33 or a vehicle. It is connected to an open / close switch (not shown) disposed in the room.

  In order to detect the rotation of the output shaft 35, a rotation sensor 66 is provided on the control board 64. The rotation sensor 66 is a Hall element, and a magnet unit 67 as a detected body is fixed to the output shaft 35 corresponding to the rotation sensor 66.

  FIG. 6 is an exploded perspective view showing a state in which the magnet unit is detached from the output shaft. The magnet unit 67 includes a sensor plate 68 formed of a steel plate and having a boss portion 68a at its axis, and a sensor plate 68. The sensor plate 68 has an annular shape including a sensor magnet 69 fixed to the outer peripheral edge of the axial end surface on the outer side in the radial direction, and is fitted and fixed to the output shaft 35 at the boss portion 68a of the sensor plate 68. It has become. The sensor magnet 69 is formed in an annular shape with the output shaft 35 as the center, and is a multipolar magnetized magnet in which a plurality of magnetic poles are magnetized in the circumferential direction.

  A receiving recess 71 that is recessed in an annular shape around the shaft center is formed on the axial end surface of the worm wheel 48 that faces away from the clutch rotor 52, that is, toward the drive drum 34. As shown in FIG. The magnet unit 67 fixed to the shaft 35 is arranged inside the housing recess 71.

  The rotation sensor 66 is exposed to the gear housing chamber 33e of the case 33 together with the control board 64 and faces the sensor magnet 69 from the axial direction. When the output shaft 35 rotates, a pulse signal having a cycle inversely proportional to the rotation speed is output. It is supposed to be. The output of the rotation sensor 66 is input to the control board 64. The control board 64 recognizes the rotation speed of the output shaft 35, that is, the opening / closing speed of the slide door 13, based on the input pulse signal, and based on this, the electric motor 44, The operation of the slide door 13 is controlled.

  The rotation sensor 66 is not limited to the Hall element, and other sensors may be used as long as they can detect the rotation of the output shaft 35 in pairs with the detection target.

  As shown in FIG. 6, the sensor plate 68 is formed with three slits 68 b that are each formed in an arc shape centered on the axis and are arranged in the circumferential direction, and the sensor plate 68 is formed by these slits 68 b. The magnetic flux path between the inside and outside is narrowed. Thus, when the clutch coil 57 is energized, the leakage magnetic flux from the clutch coil 57 that reaches the sensor magnet 69 via the output shaft 35 and the sensor plate 68 is reduced, and the rotation of the output shaft 35 by the rotation sensor 66 is reduced. The accuracy of rotation detection is increased.

  Next, the operation of the opening / closing device 21 having such a structure will be described.

  When the opening / closing switch is operated by a driver or the like, the operation of the electric motor 44 is controlled by the control board 64, and the rotation of the armature shaft 44 a is transmitted to the output shaft 35 via the worm gear mechanism 46 and the electromagnetic clutch 51. As a result, the driving drum 34 rotates, and either one of the cables 23 a and 23 b is wound around the driving drum 34 and the other cable 23 a and 23 b is rewound from the driving drum 34 according to the rotation direction. The slide door 13 is automatically opened and closed by being pulled by the cables 23a and 23b. Further, by switching the operation direction of the open / close switch, the open / close direction of the slide door 13 can be changed by reversing the electric motor 44, that is, the driving drum 34. Further, by switching the electromagnetic clutch 51 to the power cut-off state, the power transmission path between the slide door 13 and the electric motor 44 or the worm gear mechanism 46 is cut off, thereby reducing the manual opening / closing operation force of the slide door 13. Can do.

  In the structure in which the worm wheel 48 and the clutch rotor 52 are engaged and connected via the rotor ring 58 and mounted on the output shaft 35 so as to be relatively rotatable, as in the electric motor 31 with a speed reduction mechanism, the structure Further, since the worm wheel 48 and the rotor ring 58 have a slight backlash in the axial direction, the worm wheel 48 and the rotor ring 58 move in the axial direction during operation, and members such as the case 33 and the clutch rotor 52 May cause noise. Therefore, in this electric motor 31 with a speed reduction mechanism, a wave washer 81 as an urging means is attached to the output shaft 35, and the worm wheel 48 and the rotor ring 58 are directed toward the clutch rotor 52 by the wave washer 81. It is biased in the direction to absorb the play.

  As shown in FIGS. 4 and 6, the output shaft 35 is formed with an annular mounting groove 35 a along the circumferential direction so as to be positioned between the worm wheel 48 and the sensor plate 68 of the magnet unit 67. The wave washer 81 is attached to the output shaft 35 in a state of being prevented from coming off by being inserted into the attachment groove 35a. That is, the wave washer 81 is disposed between the sensor plate 68 of the magnet unit 67 and the worm wheel 48. The wave washer 81 attached to the output shaft 35 is sandwiched between the sensor plate 68 and the worm wheel 48 and is elastically deformed in the axial direction. The elastic force causes the sensor plate 68 to move to the reference position. The worm wheel 48 is urged in the axial direction toward the clutch rotor 52 side. Further, since the wave washer 81 is brought into contact with the sensor plate 68 portion of the magnet unit 67, the wave washer 81 is prevented from contacting the sensor magnet 69 without being affected.

  When the worm wheel 48 is urged toward the clutch rotor 52 by the wave washer 81, the worm wheel 48 moves in the axial direction toward the clutch rotor 52 by the amount of play, and its axial end surface is the rotor. It abuts on the disc part 59 of the ring 58. As a result, the rotor ring 58 is also urged in the axial direction toward the clutch rotor 52 by the wave washer 81 via the worm wheel 48. When the rotor ring 58 is urged toward the clutch rotor 52 by the wave washer 81, the rotor ring 58 moves toward the clutch rotor 52 by the amount of play. When the axial ring portion of the coupling protrusion 52c of the clutch rotor 52 comes into contact with the bottom of the coupling groove 61a of the rotor ring 58, the rotor ring is driven by the clutch rotor 52 that is restricted from moving in the axial direction with respect to the output shaft 35. 58, that is, the movement of the worm wheel 48 in the axial direction is restricted. Therefore, the worm wheel 48 and the rotor ring 58 are held in a state where they are urged by the wave washer 81 and pressed against the clutch rotor 52, and the play in the axial direction is absorbed simultaneously.

  As described above, in the electric motor 31 with the speed reduction mechanism, the worm wheel 48 is biased toward the clutch rotor 52 by the wave washer 81 attached to the output shaft 35. The axial backlash can be absorbed by the clutch rotor 52. Accordingly, it is possible to prevent noise generated by the worm wheel 48 moving in the axial direction when the motor is operated, and to reduce noise during the operation of the electric motor 31 with the speed reduction mechanism.

  In the electric motor 31 with a speed reduction mechanism, the rotor ring 58 is also urged toward the clutch rotor 52 by the wave washer 81 via the worm wheel 48. Can also be absorbed to prevent abnormal noise caused by the movement of the rotor ring 58 in the axial direction.

  FIG. 7 is a perspective view showing a modification of the connecting structure of the worm wheel and the rotor ring shown in FIG.

  In the case shown in FIG. 5, a connecting recess 62 that is circular in the axial center and is recessed in the axial direction is provided on the axial end surface of the worm wheel 48, and the axial end surface of the disk portion 59 of the rotor ring 58 is provided with an axis. A cylindrical connecting projection 63 protruding in the axial direction around the center is provided, and the worm wheel 48 and the rotor ring 58 are connected by combining the connecting recess 62 and the connecting projection 63 in the axial direction.

  On the other hand, in the modification shown in FIG. 7, a plurality of connecting projections 82 projecting in the axial direction toward the clutch rotor 52 side are provided on the axial end surface of the worm wheel 48 facing the clutch rotor 52 side in the circumferential direction. In addition, a plurality of connecting recesses 83 that are recessed in the axial direction toward the clutch rotor 52 side are provided side by side in the circumferential direction on the end surface in the axial direction facing the worm wheel 48 side of the disk portion 59 of the rotor ring 58. ing. Then, the worm wheel 48 and the rotor ring 58 are coupled in the axial direction so as to insert the coupling convex portion 82 of the worm wheel 48 into the coupling concave portion 83 of the rotor ring 58, thereby connecting the rotor ring 58 to the disc portion 59. Are connected to the axial end face of the worm wheel 48.

  It goes without saying that 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 above-described embodiment, the present invention is applied to the electric motor 31 with a speed reduction mechanism used in the drive unit 22 of the slide door automatic opening / closing device 21. However, the present invention is not limited to this. The present invention may be applied to an electric motor with a speed reduction mechanism used for other purposes such as a drive unit of a backdoor automatic opening / closing device that automatically opens and closes a tailgate.

  In the above embodiment, the electric motor 44 is a brushed DC motor. However, the present invention is not limited to this, and any other motor such as a brushless motor may be used as long as the armature shaft rotates in both forward and reverse directions. An electric motor may be used.

  Furthermore, in the above-described embodiment, the wave washer 81 is used as the urging means. However, the urging means is not limited to this, and the worm wheel 48 attached to the output shaft 35 is urged toward the clutch rotor 52 side. If possible, other urging means such as a coil spring or a leaf spring may be used.

It is a side view of a one box type vehicle. It is a top view which shows the attachment structure to the vehicle body of the slide door shown in FIG. It is a front view which shows the detail of the drive unit shown in FIG. It is sectional drawing which follows the AA line of the drive unit shown in FIG. (A), (b) is an exploded perspective view for demonstrating the connection structure with respect to the worm wheel of a rotor ring, and a clutch rotor, respectively. It is a disassembled perspective view which shows the state which removed the magnet unit from the output shaft. It is a perspective view which shows the modification of the connection structure of the worm wheel and rotor ring shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Vehicle 12 Car body 13 Slide door 14 Guide rail 14a Pull-in part 15 Roller assembly 21 Automatic slide door opening / closing device 22 Drive unit 23a Close side cable 23b Open side cables 24a and 24b Reverse pulley 31 Electric motor with speed reduction mechanism 32 Cable drive mechanism 33 Case 33a Drum housing chamber 33b Tensioner housing chamber 33c, 33d Cable entry / exit 33e Gear housing chamber 33f Substrate housing chamber 34 Driving drum 34a Guide groove 35 Output shaft 35a Mounting groove 36a, 36b Ball bearing 37 Nut 38a Close side tensioner pulley 38b Open side Tensioner pulleys 39a, 39b Holders 40a, 40b Guide shafts 41a, 41b Springs 42a, 42b Outer tube 43 Cover 44 Electric motor (motor body)
44a Armature shaft (rotating shaft)
45 Cover 46 Worm gear mechanism (deceleration mechanism)
47 Worm 48 Worm wheel 51 Electromagnetic clutch (clutch mechanism)
52 Clutch rotor (first clutch plate)
52a Friction surface (first engaging portion)
52b Boss portion 52c Connecting projection 53 Armature (second clutch plate)
53a Friction surface (second engaging portion)
54 Sliding bearing 55 Connecting member 56 Leaf spring 57 Clutch coil 58 Rotor ring (power transmission member)
59 Disc part 59a Through hole 61 Cylindrical part 61a Connection groove 62 Connection recessed part 62a Concave side tooth part 63 Connection convex part 63a Convex part side tooth part 64 Control board 65 Connection connector 66 Rotation sensor 67 Magnet unit (detected body)
68 Sensor plate 68a Boss portion 68b Slit 69 Sensor magnet 71 Housing recess 81 Wave washer (biasing means)
82 Connection convex part 83 Connection concave part

Claims (5)

A speed reduction mechanism comprising: a motor body having a rotation shaft; a speed reduction mechanism that decelerates rotation of the rotation shaft to output from the output shaft; and a clutch mechanism that intermittently transmits power between the rotation shaft and the output shaft. Electric motor with
A worm that rotates with the rotating shaft;
A worm wheel which is mounted on the output shaft so as to be relatively rotatable, meshes with the worm and forms the speed reduction mechanism with the worm;
A first clutch plate provided with a first engagement portion on an axial end surface, and mounted on the output shaft so as to be relatively rotatable;
A power transmission member disposed coaxially with the output shaft, coupled to the worm wheel on one side in the axial direction and coupled to the outer peripheral edge of the first clutch plate on the other side;
A second engagement portion opposed to the first engagement portion, coupled to the output shaft so as to be capable of transmitting power and engaged with the first clutch plate, and the engagement is released; A second clutch plate that is movable in the axial direction between the release position and the first clutch plate and constitutes the clutch mechanism;
An electric motor with a speed reduction mechanism, comprising: an urging means attached to the output shaft and urging the worm wheel toward the first clutch plate.   2. The electric motor with a speed reduction mechanism according to claim 1, wherein the power transmission member includes a disc portion facing an end surface in the axial direction facing the first clutch plate of the worm wheel and an outer peripheral edge of the disc portion. A cylindrical portion extending in the axial direction, coupled to the axial end surface of the worm wheel at the disc portion and coupled to an outer peripheral edge portion of the first clutch plate at the cylindrical portion, via the worm wheel An electric motor with a speed reduction mechanism, wherein the electric motor is biased toward the first clutch plate by the biasing means.   3. The electric motor with a speed reduction mechanism according to claim 1, wherein an annular detected body fixed to the output shaft, and a rotation sensor disposed in a case housing the speed reduction mechanism and facing the detected body. And the biasing means is disposed between the detected body and the worm wheel.   4. The electric motor with a speed reduction mechanism according to claim 3, wherein the detected object is formed in an annular shape in which a disc-shaped sensor plate fixed to the output shaft and a plurality of magnetic poles are magnetized in a circumferential direction. An electric motor with a speed reduction mechanism, wherein the biasing means is disposed between the sensor plate and the worm wheel.   The electric motor with a speed reduction mechanism according to any one of claims 1 to 4, wherein the urging means is a wave washer.

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