JP2013046442A - Geared motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a geared motor capable of downsizing a case by using a teeth lacking portion provided on an output member.SOLUTION: In a gear mechanism 6 of a geared motor 1, on an outer peripheral portion of a gear 64 (an output member 640) meshed with a gear 63, a teeth forming portion 646 formed with a plurality of teeth 645 in a circumferential direction, and a teeth lacking portion 647 which is not formed with the teeth 645. The teeth lacking portion 647 is equipped with a small-diameter portion 647a made from a circumference surface (an arc surface) positioned on the inner side in a diametrical direction than a tooth tip circle F64 of the teeth 645. The gear 64 (the output member 640) comes close to an inner surface 519 of a case 51 as compared with the other gear. However, when the output member 640 is driven by a motor 2 to rotate, the small-diameter portion 647a always opposes to the inner surface 519 of the case 51. Therefore, the output member 640 and the inner surface 519 of the case 51 can be made to come close to each other.

Description

  The present invention relates to a geared motor in which a motor and a gear mechanism are housed in a case.

  In the geared motor, the motor and the gear mechanism that transmits the rotation of the motor are accommodated in a common case, and the output member that outputs the rotation of the motor via the gear mechanism is configured as the final gear of the gear mechanism. Yes. Here, when the angle range (driven angle range) in which the output member rotates following the motor is less than 180 °, the output member includes a tooth portion forming portion in which a plurality of tooth portions are formed in the circumferential direction, and a tooth It may be configured as a partial gear having a partial tooth portion in which a portion is not formed (see Patent Document 1).

JP 2000-130915 A

  However, in the configuration described in Patent Document 1, the space generated by providing the missing portion on the output member is not effectively used. For this reason, there is a problem that there is a lot of wasted space in the case, and the case is large for the space occupied by the gear mechanism.

  In view of the above problems, an object of the present invention is to provide a geared motor capable of reducing the size of a case using a missing tooth portion provided in an output member.

  In order to solve the above-described problems, the present invention includes a motor, a gear mechanism that transmits the rotation of the motor, and a case that accommodates the motor and the gear mechanism inside the motor mechanism. The output member that outputs the rotation of the motor is a geared motor that constitutes the final gear of the gear mechanism, and the output member includes a tooth portion forming portion in which a plurality of tooth portions are formed in the circumferential direction, and a tooth A missing tooth portion in which a portion is not formed, the missing tooth portion comprising a small diameter portion positioned radially inward from the tip circle of the tooth portion, and the output member is another portion of the gear mechanism. The small diameter portion always faces the inner surface of the case when the gear is closer to the inner surface of the case than the gear and the output member is rotated by being driven by the motor.

  In the present invention, the output member is closer to the inner surface of the case than the other gears of the gear mechanism, but the output member is provided with a missing tooth portion having a small diameter portion located radially inward from the tip circle. In addition, when the output member rotates following the motor, the small diameter portion always faces the inner surface of the case. For this reason, since the inner surface of the case and the output member can be brought close to each other, the size of the case can be reduced.

  In the present invention, it is preferable that grease is applied to the tooth portion forming portion, and an angle range of the tooth portion forming portion is larger than an angle range in which the output member rotates following the motor. . According to such a configuration, when applying the grease while rotating the output member during assembly of the geared motor, it is possible to reliably apply the grease to the entire angle range in which the output member is driven by the motor and rotates.

  In the present invention, it is preferable that a stopper mechanism for defining an angle range in which the output member rotates following the motor is provided at an intermediate position of the gear mechanism. According to such a configuration, when the output member rotates following the front gear, it is possible to reliably prevent the tooth portion of the front gear from engaging the missing tooth portion.

  In the present invention, it is preferable that the output member is provided with a positioning portion that determines an angular position of the output member when the gear mechanism is assembled to the missing tooth portion. According to this configuration, the positioning member can be easily provided on the output member.

  In the present invention, the output member is closer to the inner surface of the case than the other gears of the gear mechanism, but the output member is provided with a missing tooth portion having a small diameter portion located radially inward from the tip circle. In addition, when the output member rotates following the motor, the small diameter portion always faces the inner surface of the case. For this reason, since a case can be made to adjoin to an output member, size reduction of a case can be attained.

It is explanatory drawing which shows the whole structure of the geared motor to which this invention is applied. It is a top view of the state which removed the cover from the geared motor to which this invention is applied. It is explanatory drawing which shows the internal structure of the geared motor to which this invention is applied. It is explanatory drawing of the gear mechanism of the geared motor to which this invention is applied. It is explanatory drawing of the meshing part of the motor pinion and gearwheel of the geared motor to which this invention is applied. It is explanatory drawing of the stopper mechanism comprised between the motor pinion and the gearwheel in the geared motor to which this invention is applied. It is a top view of the meshing part of the output member and gear of the geared motor to which the present invention is applied. It is explanatory drawing which shows a mode that phase alignment of a gearwheel and a gearwheel is performed when manufacturing the geared motor to which this invention is applied.

  An example of a gear mechanism and a motor to which the present invention is applied will be described with reference to the drawings.

(Overall structure)
FIG. 1 is an explanatory diagram showing the overall configuration of a geared motor to which the present invention is applied. FIGS. 1A, 1B, and 1C are perspective views of the geared motor and a state in which a cover is removed from the geared motor. It is the disassembled perspective view of this, and also the disassembled perspective view of the state which removed the case. FIG. 2 is a plan view of the geared motor to which the present invention is applied with the cover removed. FIG. 3 is an explanatory view showing the internal configuration of the geared motor to which the present invention is applied. FIGS. 3A and 3B show the geared motor at a position corresponding to the line SS 'in FIG. 3 is a cross-sectional view when cutting the gear mechanism, and a cross-sectional view when cutting the gear mechanism along OABCDE in FIG. 2. FIG.

  1 and 2, a geared motor 1 to which the present invention is applied generally includes a motor 2 having a stepping motor structure, a gear mechanism 6 composed of a plurality of gears, and a housing 5 in which the motor 2 and the gear mechanism 6 are accommodated. It consists of and. The housing 5 includes a cup-shaped case 51 whose upper surface is open, and a plate-shaped cover 52 that closes the opening of the case 51.

  As shown in FIG. 3A, the motor 2 is generally composed of a stator 4 and a rotor 3. The stator 4 includes two stator sets 4a and 4b that are arranged so as to overlap in the motor axial direction L. In each of the stator sets 4a and 4b, the outer stator core 41 and the inner stator core 42 face each other in the motor axial direction L. Are arranged to be. Each of the outer stator core 41 and the inner stator core 42 includes an annular flange portion and pole teeth bent in the motor axial direction L from the inner peripheral edge of the flange portion, and the outer stator core 41 and the inner stator core 42 are arranged in the motor axial direction L. In the arranged state, the pole teeth of the outer stator core 41 and the pole teeth of the inner stator core 42 are alternately arranged in the circumferential direction.

  The rotor 3 is coaxially arranged inside the stator 4. The rotor 3 includes a rotor main body 33 having a shaft hole 330 and a permanent magnet 31 fixed to the outer peripheral surface of the rotor main body 33. The outer peripheral surface of the permanent magnet 31 faces the pole teeth. . The rotor 3 is rotatably supported by a support shaft 70 fitted in the shaft hole 330. The support shaft 70 is a fixed shaft whose both ends are supported by the bottom portion 510 of the case 51 and the cover 52. In the rotor body 33, the end on the cover 52 side is a rotating shaft 35 having a motor pinion 34 on the outer peripheral surface. In the motor 2 configured as described above, the outer stator core 41 of the stator assembly 4b disposed on the opposite side (opposite output side L2) from the output side L1 from which the rotating shaft 35 protrudes is formed as a part of the case 51. .

  In each of the two stator sets 4 a and 4 b, the outer stator core 41 and the inner stator core 42 overlap each of a pair of flange portions 88 formed on the coil bobbin 86. The flange portion 88 is connected by a cylindrical portion 87 surrounding the pole teeth, and the coil 45 is wound in a region defined by the cylindrical portion 87 and the flange portion 88. The coil bobbin 86 includes a thick terminal holding portion 85 at a portion located radially outside the end face of the output side L <b> 1 of the stator 4, and the terminal holding portion 85 is formed on the side portion of the case 51. It protrudes radially outward from the notch 515 (see FIG. 1C). The terminal holding portion 85 holds a plurality of motor side terminals 99. The terminal holding part 85 is covered with the terminal cover 11 on the outer side in the radial direction and further with the outer cover 12.

(Schematic configuration of the gear mechanism 6)
FIG. 4 is an explanatory view of the gear mechanism 6 of the geared motor 1 to which the present invention is applied, and FIGS. 4A and 4B are a perspective view and an exploded perspective view of the gear mechanism 6.

  As shown in FIGS. 2, 3 (b), and 4, the geared motor 1 of this embodiment includes a gear mechanism 6 including a plurality of gears including a motor pinion 34, and the rotation of the rotor 3 of the motor 2 is performed. And output to the outside through the gear mechanism 6. In this embodiment, the gear mechanism 6 includes a total of four gears 61, 62, 63, 64 in addition to the motor pinion 34, and the final stage gear 64 is configured as an output member 640 having an output shaft 641. Has been. In the output member 640, the output shaft 641 is a plate-like portion having a shape in which a round bar portion is cut out at two opposing surfaces. For this reason, the shape of the output shaft 641 is changed in the circumferential direction, and the attachment direction when the driven member (not shown) is coupled to the output shaft 641 is directional in the circumferential direction.

  All of the three gears 61, 62, 63 except the final stage gear 64 are support shafts 71, 72, 73 supported at both ends by a base plate 55 fixed to the case 51 and a cover 52 (FIG. 3B). ))) Is rotatably supported. In the final stage gear 64, shaft portions 642 and 643 formed on itself are rotatably supported by a bearing portion 521 on the cover 52 side and a bearing portion 551 on the ground plane 55 side. In the present embodiment, the ground plate 55 includes a flat plate portion 550 and a pair of connecting plates 556 and 557 erected from a position where the flat plate portion 550 faces each other toward the output side L1. It is fixed to the inner surface of the case 51. A central hole 558 is formed in the center of the flat plate portion 550 of the base plate 55 through which the support shaft 70 and the rotation shaft 35 of the rotor 3 pass. In this embodiment, the gears 61, 62, and 63 are resin gears made of polyacetal, polybutylene terephthalate, polyamide, or the like.

  In this embodiment, the large-diameter gear portion 611 of the first gear 61 as viewed from the motor pinion 34 meshes with the motor pinion 34 formed on the outer peripheral side of the output side L1 of the rotating shaft 35, and the small-diameter gear portion of the gear 61. 612 is meshed with the large-diameter gear portion 621 of the second gear 62. The small-diameter gear portion 622 of the gear 62 meshes with the large-diameter gear portion 631 of the third gear 63, and the small-diameter gear portion 632 of the gear 63 meshes with the tooth portion 645 of the final stage gear 64. Thus, the gear mechanism 6 is configured as a reduction gear train. Here, the four gears 61, 62, 63, 64 are arranged around the motor pinion 34.

  In the geared motor 1 configured as described above, when the rotor 3 rotates by being supplied with power to the stator 4 of the motor 2, the rotation is output via the motor pinion 34, the gear 61, the gear 62, and the gear 63 to the output member 640 (gear 64. ) And the output shaft 641 rotates. In this embodiment, the rotor 3 rotates in the clockwise CW direction and the counterclockwise CCW direction, and accordingly, the output member 640 (gear 64) rotates back and forth over a predetermined angular range. Here, since the output shaft 641 of the output member 640 is a plate-like portion having a shape in which the round bar portion is cut out by two opposing surfaces, the output shaft 641 is covered in a predetermined direction using the directionality of the output shaft 641. When a driving member (not shown) is connected to the output shaft 641, the posture of the driven member can be switched using the rotation of the motor 2. At that time, the rotation range of the output member 640 in the clockwise direction CW and the rotation range of the counterclockwise direction CCW are configured between the motor pinion 34 and the gear 61 as described below with reference to FIGS. 5 and 6. Therefore, the range in which the posture of the driven member is switched is also limited by the stopper mechanism.

(Configuration of stopper mechanism of motor pinion 34 and gear 61)
FIG. 5 is an explanatory view of a meshing portion between the motor pinion 34 and the gear 61 of the geared motor 1 to which the present invention is applied, and FIGS. 5A and 5B are meshing portions between the motor pinion 34 and the gear 61. FIG. 2 is a plan view of FIG. 2 and an enlarged plan view showing a meshing portion. 6A and 6B are explanatory views of a stopper mechanism configured between the motor pinion 34 and the gear 61 in the geared motor 1 to which the present invention is applied. FIGS. 6A and 6B show the rotation of the motor pinion 34. It is a top view which shows a mode just before stopping with a stopper mechanism, and a top view which shows the state which rotation of the motor pinion 34 stopped by the stopper mechanism.

  In FIG. 5, the motor pinion 34 (first gear) has teeth 345 formed over the entire circumference, and the number of teeth is nine in this embodiment. The motor pinion 34 meshes with the large-diameter gear portion 611 of the gear 61, and the large-diameter gear portion 611 of the gear 61 engages with the tooth portion 345 of the motor pinion 34 to stop the rotation of the motor pinion 34. 8 is configured. More specifically, the outer peripheral portion of the large-diameter gear portion 611 of the gear 61 is formed with a tooth portion forming portion 616 where the tooth portion 615 is formed and a missing tooth portion 617 where the tooth portion 615 is not formed. The missing tooth portion 617 functions as the stopper portion 8.

  Here, in the missing tooth portion 617, a protruding portion 617 a that protrudes radially outward from the addendum circle F 61 of the tooth portion 615 of the gear 61 at any of the two boundary portions with the tooth portion forming portion 616, and a protruding portion A recessed portion 617b that is recessed radially inward from the protruding portion 617a is provided at a position adjacent to the tooth portion forming portion 616 in the circumferential direction with respect to 617a, and the protruding portion 617a and the recessed portion 617b are provided. They are connected in the circumferential direction.

  In this embodiment, the recessed portion 617b is recessed from the tooth tip circle F61 of the gear 61 to the inside in the radial direction. However, the recess 617b is located on the radially outer side of the pitch circle P61 of the gear 61. Here, since the pitch circle P61 of the gear 61 is located between the root circle R61 and the tooth tip circle F61, the recess 617b is radially outward from the middle between the tooth bottom circle R61 and the tooth tip circle F61. Located in. That is, it is a virtual circle having a diameter between the diameter of the root circle R61 and the diameter of the tip circle F61, and is radially outward from the virtual circle concentric with the root circle R61 and the tip circle F61. The depression 617b is located. In addition, the hollow part 617b is configured as a peripheral surface (arc surface) having a peripheral length substantially equal to the length of one tooth portion 615. Further, a portion of the missing tooth portion 617 sandwiched in the circumferential direction by the two recessed portions 617b is a circumferential surface extending in the circumferential direction on a concentric virtual circle having the same diameter as the tooth tip circle F61. (Arc surface).

  In the gear mechanism 6 configured as described above, when the motor pinion 34 rotates and the tooth portion 345 of the motor pinion 34 reaches the end portion of the tooth portion forming portion 616 as shown in FIG. The tooth portion 345 of the motor pinion 34 comes into contact with the recess 617b as shown in FIG. 6B. As a result, the rotation of the motor pinion 34 stops. 6A, when the tooth portion 345 of the motor pinion 34 comes into contact with the protruding portion 617a of the gear 61, the portion corresponding to the pitch circle P34 of the tooth portion 345 It abuts against the protrusion 617a of the gear 61. At this time, since the side surface of the protruding portion 617a of the gear 61 is inclined, the pressure angle when the portion corresponding to the pitch circle P34 of the tooth portion 345 contacts the protruding portion 617a is large. For example, the pressure angle is 50 ° or more. For this reason, the motor pinion 34 is braked. Further, as shown in FIG. 6B, when the tooth portion 345 of the motor pinion 34 contacts the recess portion 617 b, the portion close to the root side from the tip side of the tooth portion 345 contacts the recess portion 617 b of the gear 61. . Therefore, when the motor pinion 34 is stopped, the load corresponds to the contact portion between the portion corresponding to the pitch circle P34 of the tooth portion 345 and the protruding portion 617a, the tip side of the tooth portion 345, and the recessed portion 617b of the gear 61. It will be shared with the abutting part.

  As described above, in the gear mechanism 6 and the geared motor 1 according to the present embodiment, when the stopper mechanism using the engagement between the motor pinion 34 (first gear) and the gear 61 (second gear) is configured, A stopper portion 8 comprising a missing tooth portion 617 in which no tooth portion 615 is formed is provided, and the missing tooth portion 617 (stopper portion 8) has a protruding portion that protrudes radially outward from the tooth tip circle F61 of the gear 61. 617a and a recess 617b that is recessed radially inward from the protrusion 617a at a position adjacent to the protrusion 617a in the circumferential direction. For this reason, when the tooth part 345 of the motor pinion 34 contacts the recess 617b of the missing tooth part 617, the protrusion 617a also contacts the vicinity of the pitch circle P34 of the tooth part 345 of the motor pinion 34. For this reason, even when the rotation of the motor pinion 34 is stopped by the missing tooth portion 617 (stopper portion 8) provided on the gear 61, the rotational force of the motor pinion 34 does not concentrate on the tooth tip of the tooth portion 345. It breaks into 345, and damages such as deformation and cracking hardly occur.

  Further, the recess 617b is recessed from the tooth tip circle F61 of the gear 61 to the inside in the radial direction. For this reason, before the tooth part 345 of the motor pinion 34 contacts the recess 617b, the protrusion 617a reliably contacts the vicinity of the pitch circle P34 of the tooth part 345 of the motor pinion 34. For this reason, when the rotation of the motor pinion 34 is stopped by the toothless portion 617 provided in the gear 61, it is possible to reliably prevent the rotational force of the motor pinion 34 from concentrating on the tooth tip of the tooth portion 345. There is an advantage that damage to the tooth portion 345 is less likely to occur.

  Further, the recess 617 b is located on the radially outer side of the pitch circle P 61 of the gear 61. That is, it is a virtual circle having a diameter intermediate between the diameter of the root circle R61 of the gear 61 and the diameter of the tip circle F61, and is larger in diameter than the virtual circle concentric with the root circle R61 and the tip circle F61. A recess 617b is located on the outer side in the direction. For this reason, it is possible to avoid a situation in which the tooth portions 345 that are adjacent in the circumferential direction in the motor pinion 34 are in a state of being bitten with the protruding portions 617a sandwiched from both sides.

  In this embodiment, the first gear constituting the stopper mechanism is a motor pinion 34 provided on the rotating shaft 35 of the motor 2, and the second gear is a gear 61 (input gear) meshing with the motor pinion 34. ). For this reason, since the stopper mechanism (stopper portion 8) is provided in the portion where the torque is relatively small, the load applied to the tooth portion 345 is small. Therefore, the tooth portion 345 is hardly damaged.

(Configuration of output member 640)
FIG. 7 is a plan view of a meshing portion between the output member 640 and the gear 63 of the geared motor 1 to which the present invention is applied.

  As shown in FIG. 7, in the gear mechanism 6 of the geared motor 1 of this embodiment, the small-diameter gear portion 632 of the gear 63 has teeth 635 formed over the entire circumference, and in this embodiment, the number of teeth is ten. . On the other hand, on the outer peripheral portion of the gear 64 (output member 640) that meshes with the small-diameter gear portion 632 of the gear 63, a tooth portion forming portion 646 having a plurality of tooth portions 645 formed in the circumferential direction, and the tooth portion 645. And a missing tooth portion 647 in which is not formed. Therefore, in the gear 64, the missing tooth portion 647 functions as a stopper portion that engages with the tooth portion 635 of the gear 63 and prevents the rotation of the gear 63.

  Here, the missing tooth portion 647 is sandwiched between a small diameter portion 647a formed of a circumferential surface (arc surface) located radially inward of the tooth tip circle F64 of the tooth portion 645, and the small diameter portion 647a and the tooth portion forming portion 646. Large diameter portions 647b and 647c formed larger in diameter than the small diameter portion 647a, and the large diameter portions 647b and 647c are circumferential surfaces (circular arc surfaces) having the same diameter as the tip circle F64. ).

  In the geared motor 1 configured as described above, the gear 64 (output member 640) is closer to the inner surface 519 of the case 51 than the other gears 61, 62, 63, 64. However, when the output member 640 rotates following the motor 2, the small diameter portion 647 a always faces the inner surface 519 of the case 51. For this reason, the output member 640 and the inner surface 519 of the case 51 can be brought close to each other. Therefore, the case 51 can be downsized, that is, the housing 5 and the geared motor 1 can be reduced in diameter.

  In the gear mechanism 6 of the geared motor 1 configured as described above, the angular range in which the output member 640 rotates following the motor 2 is defined by the stopper portion 8 of the gear 61 described with reference to FIGS. 5 and 6. Angle (θa). On the other hand, in the output member 640, the angle range of the tooth portion forming portion 646 is θb, and the angle range θb of the tooth portion forming portion 646 is greater than the angle range θa in which the output member 640 rotates following the motor 2. It ’s big. For this reason, when the output member 640 rotates following the gear 63, the tooth portion 635 of the gear 63 does not engage with the missing tooth portion 647.

  Here, since grease is applied to the gear used in the gear mechanism 6, the grease 9 is also applied to the tooth portion 645 of the output member 640. In this embodiment, the angle range in which the output member 640 rotates following the motor 2 is θa, but the grease 9 is applied over the entire angle range θb wider than the angle range θa. That is, in this embodiment, the angle range θb of the tooth portion forming portion 646 is larger than the angle range θa in which the output member 640 is driven and rotated by the motor 2, so that the output member 640 is rotated when the geared motor 1 is assembled. Apply grease 9 while doing so. At that time, since the output member 640 can be rotated over the angular range θb of the tooth portion forming portion 646, the grease 9 can be reliably applied over the entire angular range θa that rotates following the motor 2.

(Phase matching between gear 61 and gear 64 (output member 640))
FIG. 8 is an explanatory diagram showing the phase alignment of the gear 61 and the gear 64 when the geared motor 1 to which the present invention is applied is manufactured.

  As described with reference to FIG. 5 and FIG. 6, the gear 61 has the stopper portion 8, and the angular range in which the gear 64 (output member 640 / output gear) rotates by the stopper portion 8 is θa. Is set. A driven member is connected to the output shaft 641 of the output member 640 in a predetermined direction. For this reason, it is necessary to match the phases of the gear 61 and the gear 64 (output member 640). However, the gear 61 is an input gear to which the rotation of the motor 2 is first input, and the gear 61 and the gear 64 are not directly meshed with each other through the gear 64 (the output member 640) via the other gears 62 and 63. It is the gear (front stage gear) connected in the front stage.

  Therefore, in this embodiment, as shown in FIG. 7 and the like, the gear 64 is formed with a first hole 649 (positioning portion) that indicates the angular position of the gear 64. In the present embodiment, the first hole 649 is formed by utilizing the missing tooth portion 647 of the gear 64. More specifically, the first hole 649 is formed in the large-diameter portion 647c having a longer peripheral length among the large-diameter portions 647b and 647c of the missing tooth portion 647. Here, the 1st hole 649 is formed as a hole of a perfect circle in the inner peripheral outline shape in which the outer edge of the large-diameter portion 647c is partially broken and opened. However, in the first hole 649, the inner peripheral wall 649a exists over an angle range of 180 ° or more. In the present embodiment, the first hole 649 has an inner peripheral wall 649a over an angle range of approximately 200 °.

  On the other hand, as shown in FIG. 5 and the like, the gear 61 is formed with a second hole 619 indicating the angular position of the gear 61. In this embodiment, the second hole 619 is formed in a portion corresponding to the missing tooth portion 617 in the large-diameter gear portion 611 of the gear 61. Here, the second hole 619 is formed as an elliptical or elliptical hole whose inner peripheral contour shape has its long axis in the circumferential direction.

  Therefore, when the gear mechanism 6 is assembled in the manufacturing process of the geared motor 1, first, as shown in FIG. 8A, the support shafts 71 and 72 are mounted on the base plate 55 using a jig (not shown). , 73 are attached, the round bar-shaped first pin 91 and the round bar-shaped second pin 92 are erected inside the central hole 558 of the main plate 55. Here, the first pin 91 is raised at a predetermined angular position centered on the rotation center (bearing portion 551) of the gear 64, and the rotation center (support shaft 71) of the gear 61 is set for the second pin 92. It stands up at a predetermined angular position as the center.

  Next, the output member 640 and the gears 61, 62, 63 are arranged. 8B, when the output member 640 is disposed so as to be fitted to the bearing portion 551, the position where the first hole 649 is fitted to the first pin 91 is the assembly angle position of the output member 640. And Further, when the gear 61 is arranged so as to be fitted to the support shaft 71, the position where the second hole 619 is fitted to the second pin 92 is set as the assembly angle position of the gear 61.

  Thereafter, the gear 63 is engaged with the output member 640 as shown in FIG. Further, the gear 62 is meshed with the gear 63. At this time, the gear 62 is engaged with the gear 61. Since the second hole 619 is an oval or elliptical hole, the angle of the gear 61 is maintained while the second pin 92 is fitted in the second hole 619. The gear 62 and the gear 61 are meshed by finely adjusting the position.

  When the gear mechanism 6 is assembled to the main plate 55 in this way, the phases of the gear 61 and the gear 64 (output member 640) can be matched.

  As described above, in this embodiment, the output member 640 has the first hole 649 that indicates the angular position of the output member 640, and is connected to the output member 640 via the other gears 62 and 63. A second hole 619 indicating the angular position of the gear 61 is formed in the gear 61. For this reason, after determining the angular positions of the output member 640 and the front gear 61 based on the first hole 649 and the second hole 619, the other gear 62, between the output member 640 and the front gear 61, If 63 is assembled, the other gears 62 and 63 can be assembled in a state in which the phase between the output member 640 and the preceding gear 61 is adjusted. Therefore, the phases can be matched even with gears that are not directly meshed with each other. Further, unlike the case where the phase is adjusted using missing teeth, the meshing rate does not decrease even when the number of teeth is small.

  Here, the first hole 649 is a perfect circle with an inner peripheral contour shape, and the second hole 619 is an ellipse or an ellipse whose inner peripheral contour shape has a major axis in the circumferential direction. For this reason, the angular position of the output member 640 can be accurately adjusted, and the meshing clearance can be adjusted by the front gear 61.

  Further, in the first hole 649, the inner peripheral wall 649a exists over an angle range of 180 ° or more. Therefore, after the first pin 91 is fitted in the first hole 649 and before the assembly is completed, Inclination can be prevented.

  In addition, as described with reference to FIG. 7 and the like, the output member 640 includes a tooth portion forming portion 646 in which a plurality of tooth portions 645 are formed in the circumferential direction, and a missing tooth portion 647 in which the tooth portions 645 are not formed. And the missing tooth portion 647 functions as a stopper portion. For this reason, even when the first pin 91 is pulled out after the gear mechanism 6 is assembled, the output member 640 can be prevented from rotating excessively. In this embodiment, since the first hole 649 serving as the positioning portion for the gear 64 is formed in the missing tooth portion 647, the first hole 649 ( There is an advantage that the positioning portion can be easily formed.

[Other embodiments]
In the above embodiment, the stopper portion 8 is provided on the input gear (gear 61), but may be provided on the other gears 62, 63 and the like.

  In the above embodiment, the stopper portion 8 is provided in the gear mechanism 6 of the geared motor 1 using the motor 2 as a drive source. However, the stopper portion 8 is provided in the gear mechanism 6 of a device other than the geared motor 1 using the motor 2 as a drive source. The present invention may be applied in the case of providing

  In the above embodiment, the stopper portion 8 is provided with the protruding portions 617a at two locations that are spaced apart in the circumferential direction, and the recessed portion 617b is provided at each of the two protruding portions 617a, but the protruding portions 617a provided at the two locations. You may employ | adopt the structure which becomes the hollow part 617b where the space | interval continued.

  In the above embodiment, the first hole 649 and the second hole 619 are used to adjust the angular position between the gear 61 (front gear) and the gear 64 (output gear). The first hole 649 and the second hole may be used to adjust the angular position of the gears 62 and 63. In addition, the first hole 649 may have a shape in which the outer periphery is not cut out, and the second hole 619 may be a circle other than an ellipse or an ellipse.

  In the above embodiment, three gears 61, 62, 63 are interposed between the motor pinion 34 and the gear 64, but one gear or four or more gears are interposed between the motor pinion 34 and the gear 64. The present invention may be applied to the interposing gear mechanism 6.

1 Geared Motor 2 Motor 3 Rotor 4 Stator 6 Gear Mechanism 8 Stopper 9 Grease 34 Motor Pinion (First Gear)
51 Case 55 Base plate 61 Gear (input gear / front gear / second gear)
62 Gears (other gears)
63 Gears (other gears)
64 gears (output gears)
91 1st pin 92 2nd pin 616 Tooth portion forming portion 617 Notched tooth portion 617a Protruding portion 617b Depressed portion 619 Second hole 646 Tooth portion forming portion 647 Notched tooth portion 647a Small diameter portion 647b, 647c Large diameter portion 649 First hole

Claims (4)

An output member that outputs the rotation of the motor via the gear mechanism, and a gear mechanism that transmits the rotation of the motor; and a case that accommodates the motor and the gear mechanism therein. A geared motor constituting the final gear of the mechanism,
The output member includes a tooth portion forming portion in which a plurality of tooth portions are formed in the circumferential direction, and a missing tooth portion in which the tooth portion is not formed,
The missing tooth portion includes a small diameter portion located radially inward from the tip circle of the tooth portion,
The output member is closer to the inner surface of the case than the other gears of the gear mechanism, and when the output member rotates following the motor, the small diameter portion always faces the inner surface of the case. Geared motor characterized by While the tooth forming part is coated with grease,
The geared motor according to claim 1, wherein an angle range of the tooth portion forming portion is larger than an angle range in which the output member rotates following the motor.   The geared motor according to claim 2, wherein a stopper mechanism that defines an angle range in which the output member rotates following the motor is provided at an intermediate position of the gear mechanism.   4. The output member according to claim 1, further comprising a positioning portion that determines an angular position of the output member when the gear mechanism is assembled to the missing tooth portion. 5. Geared motor.