JP2015038373A - Friction mechanism and geared motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a friction mechanism which inhibits strength deterioration by welding and variations in friction torque even when a gear member is formed by resin molding, and to provide a geared motor including the friction mechanism.SOLUTION: A friction mechanism 9 includes: a gear member 92 where a gear part 926 is formed at a cylindrical trunk part 923 extending in a motor axis line direction S; a rotary member 91 including multiple elastic deformation parts 915; and a biasing member 93 which biases the elastic deformation parts 915 and causes the elastic deformation parts 915 to elastically contact with an inner peripheral surface 923p of the trunk part 923. When the gear member 92 is resin molded, a ring gate is disposed at a position in a mold which excludes portions where the gear part 926 and the inner peripheral surface 923p are formed. Thus, a ring gate cutting part is located in a part of the gear member 92 which excludes the gear part 926 and the inner peripheral surface 923p.

Description

  The present invention relates to a friction mechanism provided in a gear train and the like, and a geared motor including the friction mechanism.

  As a friction mechanism for protecting gears and motors used in gear trains in geared motors, etc., the elastically deforming part of the rotating member is elastically brought into contact with the inner peripheral surface of the cylindrical body of the gear member by the biasing member. A mechanism that has been proposed has been proposed (see Patent Document 1).

JP 2010-78009 A

  In constructing the friction mechanism described in Patent Document 1, if a three-point gate method is employed when forming the gear member by resin molding, a weld is generated between the gate cut portions, resulting in a decrease in strength. There is. Further, when the molding is performed by the three-point gate method, since the flow of the resin is unstable, there is a problem that the roundness of the inner peripheral surface that slides on the rotating member in the trunk portion is low and the friction torque is likely to vary.

  In view of the above problems, an object of the present invention is to provide a friction mechanism capable of suppressing a decrease in strength due to welds and variations in friction torque even when the gear member is formed by resin molding, and a geared equipped with the friction mechanism. It is to provide a motor.

  In order to solve the above-described problems, in the present invention, a gear member having a gear portion formed on a cylindrical trunk portion extending in the axial direction, and a diameter on one outer surface of the outer side and the inner side of the trunk portion. A rotating member having a plurality of elastically deforming portions that are elastically contacted from the direction, and the gear member is made of resin, and the ring gate cutting portion is located at a position excluding the gear portion and the one peripheral surface. It is characterized by being.

  In the present invention, unless an excessive load is applied to the rotating member or the gear member, the rotating member and the gear member rotate integrally by the frictional engagement force between the rotating member and the gear member. On the other hand, when a large load is applied to one of the rotating member and the gear member, idle rotation occurs between the rotating member and the gear member. Therefore, a gear or a motor connected to the rotating member or the gear member is used. Can be prevented from being damaged. Here, the gear member is made of resin, but is manufactured by molding using a ring gate. For this reason, unlike the case where the three-point gate method is adopted, there is no generation of welds, so that the strength is sufficient. Further, unlike the case where the three-point gate method is adopted, the resin flow at the time of molding is stable, so that the roundness of the peripheral surface that slides with the rotating member in the trunk portion is improved. Therefore, a stable friction torque can be obtained. Further, since the ring gate is disposed at a position excluding the gear portion and the one peripheral surface, the ring gate cutting portion does not remain on the gear portion or the one peripheral surface. Therefore, the ring gate cutting portion does not hinder the operation of the gear train using the gear member and the friction mechanism.

  In this invention, the said gear part is provided in the one end part of the said axial direction of the said trunk | drum, and the said ring gate cutting | disconnection part is provided in the other end side of the said axial direction from the said gear part in the said trunk | drum. It is preferable that there is. According to such a configuration, at the time of molding, the portion that forms the gear portion is filled with the resin at a high pressure, so that the gear portion can be formed with high accuracy.

  In the present invention, it is preferable that the ring gate cutting portion is located on the other end side of the trunk portion from the intermediate position in the axial direction. According to such a configuration, the resin is filled at a high pressure in the portion forming the gear portion during molding. For this reason, a gear part can be formed with high precision.

  In this invention, it is preferable that the said ring gate cutting part exists in the cyclic | annular end surface which faces the other side of the said axial direction in the said trunk | drum. According to this configuration, since the resin easily flows in the axial direction during molding, the gear portion and the like can be formed with high accuracy.

  In the present invention, the body portion includes a first annular end face facing the other side in the axial direction, a second annular end face facing the other side in the axial direction on one side in the axial direction from the first annular end face, It is preferable that the ring gate cutting portion is provided on the second annular end face. According to such a configuration, even if there is a ring gate cutting portion on the second annular end surface, the first annular end surface is on the other side in the axial direction from the second annular end surface. The ring gate cut portion does not remain as a convex portion at the other end.

  In the present invention, it is preferable that the first annular end surface overlaps the rotating member in the axial direction to position the rotating member on one side in the axial direction.

  In this invention, you may employ | adopt the structure which has the said ring gate cutting part in the edge of the annular end surface which has faced the other side of the said axial direction in the said trunk | drum.

  In this invention, you may employ | adopt the structure which has the said ring gate cutting part in the other surrounding surface of the outer side and the inner side of the said trunk | drum.

  In the present invention, the body portion includes a first body portion, and a second body portion that is formed on one side in the axial direction from the first body portion and has an outer diameter larger than that of the first body portion. It is preferable that the gear portion is formed on the other peripheral surface of the outer side and the inner side of the second body portion. According to this structure, a gear part can be formed in the 2nd trunk | drum (large diameter part) of a gear member. In addition, since the gear portion is formed in a portion that protrudes radially outward in the body portion, even when a member such as another gear is located on the other side in the axial direction with respect to the gear portion, it interferes with the gear member. do not do.

  In the present invention, it is preferable to have a biasing member that biases the elastic deformation portion in the radial direction and elastically contacts the elastic deformation portion with the one peripheral surface. According to this configuration, the elastic deformation portion can be brought into contact with the peripheral surface of the gear member with a predetermined elasticity, so that an appropriate frictional engagement force can be generated.

  In this case, it is preferable that the urging member is disposed at a position overlapping the gear portion when viewed from the radial direction. Since the gear portion is formed thick, even if the urging force of the urging member is applied to the body portion of the gear member, deformation or cracking due to stress is unlikely to occur in the body portion of the gear member. Further, since the gear portion is formed with high accuracy, an appropriate frictional engagement force can be generated.

  The friction mechanism according to the present invention is used in a geared motor. In this case, the geared motor includes a motor unit, an output member, and a gear train that transmits the rotation of the motor to the output member, and one of the two gears included in the gear train is the gear. It is a member and the other is the said rotation member, It is characterized by the above-mentioned.

  In the present invention, the gear member is made of resin, but is manufactured by molding using a ring gate cutting portion. For this reason, unlike the case where the three-point gate method is adopted, there is no generation of welds, so that the strength is sufficient. Unlike the three-point gate system, the flow of resin during molding is stable, and the roundness of the peripheral surface that slides with the rotating member in the body improves, so stable friction torque is achieved. Can be obtained. Further, since the ring gate is disposed at a position excluding the gear portion and the one peripheral surface, the ring gate cutting portion does not remain on the gear portion or the one peripheral surface. Therefore, the ring gate cutting portion does not hinder the operation of the gear train using the gear member and the friction mechanism.

It is explanatory drawing of the geared motor which concerns on Embodiment 1 of this invention. It is explanatory drawing of the friction mechanism mounted in the geared motor which concerns on Embodiment 1 of this invention. It is explanatory drawing when the friction mechanism mounted in the geared motor which concerns on Embodiment 1 of this invention is seen from the non-output side. It is explanatory drawing of the gear member used for the friction mechanism of the geared motor which concerns on Embodiment 1 of this invention. It is explanatory drawing of the gear member used for the friction mechanism of the geared motor which concerns on Embodiment 2 of this invention. It is explanatory drawing of the gear member used for the friction mechanism of the geared motor which concerns on Embodiment 3 of this invention. It is explanatory drawing of the gear member used for the friction mechanism of the geared motor which concerns on Embodiment 4 of this invention.

  Embodiments of the present invention will be described with reference to the drawings. In the friction mechanism according to the present invention, the elastic deformation portion of the rotating member may be in contact with either the outer surface or the inner peripheral surface of the gear member body. Description will be made centering on the form in which the elastic deformation portion of the rotating member is in contact with the inner peripheral surface. Therefore, “one peripheral surface” in the present invention is an “inner peripheral surface”, and “the other peripheral surface” is an “outer peripheral surface”. In the friction mechanism according to the present invention, the gear portion may be formed at either the output side or the counter-output side end portion of the gear member body. Description will be made centering on a form in which a gear portion is formed at the output side end. Therefore, “one side in the axial direction” in the present invention is “the output side”, and “the other side in the axial direction” is “the opposite output side”. In the following description, not only the axial direction of the motor unit 2 but also the direction parallel to the axial direction of the motor unit 2 will be described as “motor axial direction S”.

[Embodiment 1]
(Overall structure)
FIG. 1 is an explanatory diagram of a geared motor according to Embodiment 1 of the present invention, and FIGS. 1 (a), (b), and (c) are cross-sectional views showing the configuration of a gear train of the geared motor, It is the expanded view which shows the meshing state of the gearwheel in the longitudinal cross-sectional view and a gear train.

  1A, 1B and 1C, a geared motor 1 to which the present invention is applied includes a motor unit 2 having a stepping motor structure. The motor unit 2 includes a stator 4 and a rotor 3. It is roughly composed. The stator 4 includes two stator sets 4a and 4b that are arranged so as to overlap in the motor axial direction S. In the stator sets 4a and 4b, the outer stator core 41 and the inner stator core 42 are opposed to each other in the motor axial direction S. Is arranged. 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 S 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 S. 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 51 of the motor case 5 and the motor cover 50 that covers the upper surface of the motor case 5. In the rotor body 33, the end on the motor cover 50 side is a rotating shaft 34 having a rotor pinion 35 on the outer peripheral surface. In the motor unit 2 configured as described above, when the side from which the rotating shaft 34 protrudes is the output side S1, and the opposite side is the non-output side S2, the outer stator core 41 is the motor case in the stator set 4b on the non-output side S2. 5 is formed as a part of the bottom 51.

  The inner stator core 42 of the two stator sets 4 a and 4 b is insert-molded when the coil bobbin 86 is formed of resin, and is covered with the flange portion 88 of the coil bobbin 86. At that time, a terminal holding portion 85 is also formed in the resin portion 8. The resin portion 8 includes a cylindrical portion 87 surrounding the pole teeth and an annular flange portion 88 whose diameter is increased at the end in the motor axial direction S of the cylindrical portion 87 at a portion constituting the coil bobbin 86. The coil 45 is wound in an area defined by the cylindrical portion 87 and the flange portion 88. The coil 45 is a two-phase coil in which two windings are wound around each of the two stator sets 4a and 4b, and an intermediate portion of the coil 45 wound around the stator sets 4a and 4b is common. It is drawn out as a winding. For this reason, the number of winding ends pulled out from the stator 4 is 5, and the winding ends are tangled to the motor-side terminal 191 held by the terminal holding portion 85 and then soldered. Thus, the motor side terminal 191 is electrically connected. A connector housing 11 that holds an external connection terminal 192 is disposed on the outer peripheral side of the motor side terminal 191, and the motor side terminal 191 and the external connection terminal 192 are electrically connected via the flexible wiring board 12.

  The geared motor 1 of this embodiment includes a gear train 6 composed of a plurality of gears, and the rotation of the rotor 3 of the motor unit 2 is output to the outside via the gear train 6. In this embodiment, the gear train 6 includes a total of five gears 61, 62, 63, 64, 65, and the final stage gear 65 includes an output shaft 651 (output member). Here, all of the four gears 61, 62, 63, 64 except the final stage gear 65 are support shafts 71, 72 supported at both ends by the base plate 55 fixed to the motor case 5 and the motor cover 50. , 73 and 74, and the final stage gear 65 has shaft parts 652 and 653 formed on itself that can rotate to a bearing part 501 on the motor cover 50 side and a bearing part 551 on the main plate 55 side. It is supported by.

  In the present embodiment, the large-diameter gear portion 611 of the first gear 61 meshes with the rotor pinion 35 formed on the outer peripheral side of the output side S1 of the rotating shaft 34, and the small-diameter gear portion 612 of the gear 61 includes A large-diameter gear portion 926 of the second gear 62 is engaged. The small diameter gear portion 914 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 large diameter gear portion 641 of the fourth gear 64. doing. The gear portion 655 of the final stage gear 65 meshes with the small-diameter gear portion 642 of the gear 64. Thus, the gear train 6 is configured as a reduction gear train. Here, the five gears 61, 62, 63, 64, 65 are arranged around the rotor pinion 35.

(Configuration of friction mechanism)
FIG. 2 is an explanatory view of the friction mechanism mounted on the geared motor 1 according to the first embodiment of the present invention. FIGS. 2 (a), (b), (c), and (d) each show the friction mechanism. It is the perspective view seen from the output side, sectional drawing, the disassembled perspective view seen from the output side, and the disassembled perspective view which looked at the mode further disassembled from the output side. FIG. 3 is an explanatory diagram when the friction mechanism mounted on the geared motor 1 according to Embodiment 1 of the present invention is viewed from the counter-output side, and FIGS. 3A, 3B, and 3C are respectively FIG. 4 is a perspective view of the friction mechanism as viewed from the non-output side, an exploded perspective view as viewed from the non-output side, and an exploded perspective view of the further disassembled state as viewed from the non-output side.

  In the geared motor 1 described with reference to FIG. 1, when the motor unit 2 operates in the state where an excessive load is applied to the output shaft 651, the gears 61, 62, 63, 64, 65 used for the gear train 6 are used. In addition, the rotor pinion 35 may be damaged. Therefore, a friction mechanism 9 that functions as a torque limiter is provided in the middle of the gear train 6. In the present embodiment, among the gears 61, 62, 63, 64, 65 used for the gear train 6, the friction mechanism 9 is configured in the gear 62.

  2 and 3, the friction mechanism 9 formed on the gear 62 includes a rotating member 91 made of resin such as POM (polyacetal), a gear member 92 made of resin such as PBT (polybutylene terephthalate), and an urging force. In this embodiment, the urging member 93 is a stainless steel C-shaped washer cut at one location in the circumferential direction.

  The rotating member 91 is a resin molded product such as polyacetal resin, and includes a cylindrical central shaft portion 911 extending to the output side S1 in the motor axial direction S of the gear 62, and a middle portion in the length direction of the central shaft portion 911. And a disk-shaped flange portion 912 protruding in the radial direction. In the central shaft portion 911, a gear portion 914 is formed on the outer peripheral side surface of the shaft end portion 913 protruding from the flange portion 912 to the opposite output side S2, and the gear portion 914 is the third gear shown in FIG. This is a small-diameter gear meshing with 63. Further, the central shaft portion 911 is formed with a shaft hole 910 into which the support shaft 72 shown in FIG.

  In the rotating member 91, a plurality of plate-like elastic deformation portions 915 extend from the outer peripheral edge of the flange portion 912 toward the output side S1 in the motor axial direction S. The elastic deformation portions 915 are circular in the circumferential direction. Curved in an arc. In this embodiment, two elastic deformation portions 915 are arranged in the circumferential direction and have a structure in which a cylindrical portion is divided by a slit 917. In the rotating member 91, an annular groove 916 is formed between the inner peripheral side surface of the elastic deformation portion 915 and the outer peripheral side surface of the central shaft portion 911.

  Inside the annular groove 916, a C-shaped washer-like urging member 93 is press-fitted. A coil spring can also be used as the urging member 93. Here, the inner diameter dimension of the urging member 93 in a state where no external force is applied is sufficiently larger than the outer diameter dimension of the central shaft portion 911. Further, the outer diameter of the biasing member 93 in a state where no external force is applied is larger than the diameter of the circle defined by the inner peripheral surface of the elastic deformation portion 915. For this reason, when the urging member 93 is press-fitted into the annular groove 916, the urging member 93 is deformed into a reduced diameter state, and the elastic deformation portion 915 is pushed outward in the radial direction by its shape restoring force (spring force). A small step 915e is formed on the inner peripheral side surface of the elastic deformation portion 915, and the position of the biasing member 93 in the motor axial direction S is defined by the step 915e.

  In the rotating member 91 configured as described above, the first convex portion 918 that protrudes radially outward from the circumferential center position of the elastic deformation portion 915 is formed at the end of the output side S1 of the two elastic deformation portions 915. In the outer peripheral surface of the elastic deformation portion 915, a portion located on the opposite output side S2 with respect to the first convex portion 918 is a flat surface 915c.

  Further, at the end on the counter-output side S2 of the rotating member 91, a second convex portion 919 is formed on the outer peripheral surface of the disc-shaped flange portion 912 that protrudes radially outward from two locations in the circumferential direction. The second protrusion 919 protrudes radially outward from the slit 917. A concave portion 919a is formed on the surface of the second convex portion 919 on the side opposite to the output side S2.

(Configuration of gear member 92)
FIG. 4 is an explanatory diagram of the gear member 92 used in the friction mechanism 9 of the geared motor 1 according to the first embodiment of the present invention. FIGS. 4 (a), 4 (b), 4 (c), and 4 (d) They are a plan view, a side view, an exploded perspective view, and a cross-sectional view, as seen from the output side S1, of the gear member 92, respectively.

  As shown in FIGS. 2 and 4, the gear member 92 includes a cylindrical body 923 extending in the motor axial direction S of the gear 62. The body 923 includes a first body 928 and a second body 929 formed on the output side S1 in the motor axial direction S from the first body 928. The second body 929 has an outer diameter dimension. It is larger than the first body portion 928.

  A gear portion 926 is formed on the outer peripheral surface of the second body portion 929, and the gear portion 926 is a large-diameter gear that meshes with the first gear 61 shown in FIG. The center hole of the gear member 92 is a fitting hole 921 into which the elastic deformation portion 915 of the rotating member 91 is fitted.

  At the end portion 923b of the body portion 923 on the counter-output side S2 (the end portion 923b of the first body portion 928 on the counter-output side S2), the annular protrusion 927 extends from the radially inner side of the first body portion 928 toward the counter-output side S2. Is protruding. Therefore, a first annular end surface 924 is formed on the body portion 923 by the annular protrusion 927 and faces the opposite output side S <b> 2 in the motor axial direction S. The motor is connected to the outer side of the annular protrusion 927 in the radial direction from the first annular end surface 924. A second annular end surface 925 is formed on the output side S1 in the axial direction S and facing the opposite output side S2 in the motor axial direction S. In addition, an annular stepped portion having an end surface directed toward the output side S1 along the edge of the fitting hole 921 is formed at the end portion 923a of the output side S1 of the body portion 923 (the end portion 923a of the output side S1 of the second body portion 929). 921b is formed.

  In order to configure the friction mechanism 9 (gear 62) using the gear member 92, the rotating member 91, and the urging member 93 configured as described above, the elastic deformation portion of the gear member 92 without the urging member 93 attached. 915 is elastically deformed inward, and in this state, the elastic deformation portion 915 of the rotating member 91 is fitted into the fitting hole 921 of the gear member 92 from the non-output side S2, and then the output side S1 is moved to the inside of the elastic deformation portion 915. The urging member 93 is pushed in. Alternatively, the elastic deformation portion 915 of the gear member 92 is elastically deformed in the state where the urging member 93 is mounted, and in this state, the elastic force of the rotating member 91 from the counter-output side S2 to the fitting hole 921 of the gear member 92. The deformable portion 915 may be fitted. In any case, the biasing member 93 presses the elastic deformation portion 915 radially outward at a position overlapping the gear portion 926 when viewed from the radial direction. As a result, the elastic deformation portion 915 abuts on the inner peripheral surface 923p of the fitting hole 921 (the inner peripheral surface 923p of the trunk portion 923) with elasticity and frictionally engages. Therefore, as long as an excessive load is not applied to the rotating member 91, the rotating member 91 and the gear member 92 rotate together by the frictional engagement force between the rotating member 91 and the gear member 92. On the other hand, when a large load is applied to the rotating member 91, idle rotation occurs between the rotating member 91 and the gear member 92, so that the gear and the motor connected to the rotating member 91 and the gear member 92 are damaged. Can be prevented.

  In this embodiment, when the elastic deformation portion 915 of the rotating member 91 is fitted into the fitting hole 921 of the gear member 92 from the opposite output side S2, the first convex portion 918 of the rotating member 91 is the annular step portion 921b of the gear member 92. Are engaged so as to cover from the output side S1. For this reason, the gear member 92 is positioned at the counter-output side S2 by the annular step portion 921b, and is prevented from coming off from the fitting hole 921. Further, when the elastic deformation portion 915 of the rotating member 91 is fitted into the fitting hole 921 of the gear member 92 from the non-output side S <b> 2, the second convex portion 919 of the rotating member 91 is formed on the first annular end surface 924 of the gear member 92. The gear member 92 is in contact with the first annular end surface 924, and the position to the output side S1 is determined.

(Manufacturing method of the gear member 92)
In this embodiment, the gear member 92 is a resin molded product such as PBT. When the gear member 92 is molded, a gear portion 926 and an inner peripheral surface 923p are formed in the mold as shown in FIG. A ring gate G is arranged at a position excluding the portion to be formed as schematically shown by an arrow. For this reason, the gear member 92 has a ring gate cutting part G0 at a position excluding the gear part 926 and the inner peripheral surface 923p, as shown by a one-dot chain line in FIG.

  In particular, in the present embodiment, the ring gate G is disposed on the side of the end 923b on the counter-output side S2 from the portion where the gear portion 926 is formed in the mold. For this reason, in the gear member 92, the ring gate cutting part G0 is located on the side of the end 923b on the counter-output side S2 from the gear part 926. In particular, the ring gate G is disposed on the end 923b side on the counter-output side S2 from the intermediate position in the motor axial direction S in the portion of the mold that forms the body portion 923. For this reason, in the gear member 92, there is a ring gate cutting part G0 on the end 923b side on the counter-output side S2 from the intermediate position of the body part 923 in the motor axial direction S.

  More specifically, in the present embodiment, the ring gate G is disposed in a portion of the mold where the second annular end surface 925 that faces the counter-output side S2 in the motor axial direction S of the body portion 923 is formed. For this reason, in the gear member 92, in the trunk portion 923, there is a ring gate cutting portion G0 on the second annular end surface 925 facing the opposite output side S2 in the motor axial direction S.

(Main effects of this form)
As described above, in this embodiment, the gear member 92 is made of resin, but is manufactured by molding using the ring gate G. For this reason, unlike the case where the three-point gate method is adopted, there is no generation of welds, so that the strength is sufficient. Unlike the case where the three-point gate method is adopted, the resin flow at the time of molding is stable, so that the roundness of the inner peripheral surface 923p that slides on the rotating member 91 in the trunk portion 923 is improved. Therefore, a stable friction torque can be obtained. Further, since the ring gate G is disposed at a position excluding the gear portion 926 and the inner peripheral surface 923p, the ring gate cutting portion G0 does not remain on the gear portion 926 or the inner peripheral surface 923p. Therefore, the ring gate cutting part G0 does not hinder the operation of the gear train 6 and the friction mechanism 9 using the gear member 92.

  Further, the ring gate G is arranged on the side of the end 923b on the counter-output side S2 from the portion where the gear portion 926 is formed in the mold. In particular, in the present embodiment, the ring gate G is disposed on the end 923b side on the counter-output side S2 from the intermediate position in the motor axial direction S in the portion of the mold that forms the body portion 923. For this reason, since the gear part 926 is shape | molded in the position far from the ring gate G, the resin is filled with the high pressure in the part which forms the gear part 926 at the time of shaping | molding. Therefore, the gear portion 926 can be formed with high accuracy.

  Further, in this embodiment, the ring gate G is disposed in a portion of the mold that forms the second annular end surface 925 that faces the opposite output side S2 of the body portion 923 in the motor axial direction S. For this reason, since resin tends to flow to the output side S1 in the motor axial direction S during molding, the gear portion 926 and the like can be formed with high accuracy.

  Further, the second annular end surface 925 is located on the output side S1 in the motor axial direction S from the first annular end surface 924. For this reason, even if the ring gate cutting part G0 is present on the second annular end face 925, the ring gate cutting part G0 is formed at the end of the body 923 in the axial direction (first annular end face 924). Does not remain as protrusions. Therefore, the first annular end surface 924 can be used for positioning the rotating member 91 in the motor axial direction S.

  Further, an urging member 93 that urges the elastic deformation portion 915 in the radial direction and elastically contacts the elastic deformation portion 915 with the inner peripheral surface 923p of the gear member 92 is used. For this reason, since the elastic deformation part 915 can be made to contact the inner peripheral surface 923p of the gear member 92 with a predetermined elasticity, an appropriate frictional engagement force can be generated.

  Further, when viewed from the radial direction, the biasing member 93 is disposed at a position overlapping the gear portion 926. Since the gear portion 926 is formed thick, even if the urging force of the urging member 93 is applied to the body portion 923 of the gear member 92, the body portion 923 of the gear member 92 is not deformed or cracked due to stress. Hard to occur. Moreover, since the gear part 926 is formed with high accuracy, an appropriate frictional engagement force can be generated.

  Further, since the gear portion 926 is formed on the second barrel portion 929 that projects outward in the radial direction at the trunk portion 923, other gears or the like are disposed on the opposite output side S2 in the motor axial direction S with respect to the gear portion 926. Even when the member is located, it does not interfere with the gear member 92.

[Embodiment 2]
FIG. 5 is an explanatory diagram of a gear member 92 used in the friction mechanism 9 of the geared motor 1 according to the second embodiment of the present invention. FIGS. 5 (a), 5 (b), 5 (c), and 5 (d) They are a plan view, a side view, an exploded perspective view, and a cross-sectional view, as seen from the output side S1, of the gear member 92, respectively. Since the basic configuration of the present embodiment and later-described third and fourth embodiments is the same as that of the first embodiment, common portions are denoted by the same reference numerals and description thereof is omitted. To do.

  The gear member 92 shown in FIG. 5 is also a resin molded product such as PBT as in the first embodiment. In this embodiment, when the gear member 92 is formed, as shown in FIG. 5D, a second annular end surface 925 that faces the opposite output side S2 in the motor axial direction S of the body portion 923 is formed in the mold. A ring gate G is arranged on the outer edge of the part. Therefore, in the gear member 92, the ring portion 923 has a ring gate cutting portion G0 at the outer edge 925e of the second annular end surface 925 facing the opposite output side S2 in the motor axial direction S.

  Accordingly, in this embodiment, as in the first embodiment, the ring gate cutting portion G0 does not remain on the gear portion 926 and the inner peripheral surface 923p, so that the ring gate is used for the operation of the gear train 6 and the friction mechanism 9 using the gear member 92. The cutting part G0 does not hinder. Further, since the ring gate G is arranged on the side of the end 923b on the counter-output side S2 from the portion where the gear portion 926 is formed in the mold, the gear portion 926 is formed at a position far from the ring gate G. For this reason, at the time of molding, since the resin forming portion is filled with resin at a high pressure, the gear portion 926 can be formed with high accuracy, and the same effects as in the first embodiment can be obtained.

[Embodiment 3]
FIG. 6 is an explanatory diagram of the gear member 92 used in the friction mechanism 9 of the geared motor 1 according to the third embodiment of the present invention. FIGS. 6 (a), (b), (c), and (d) They are a plan view, a side view, an exploded perspective view, and a cross-sectional view, as seen from the output side S1, of the gear member 92, respectively.

  The gear member 92 shown in FIG. 6 is also a resin molded product such as PBT, as in the first embodiment. In the present embodiment, when the gear member 92 is formed, as shown in FIG. 6D, the portion that forms the outer peripheral surface 923r of the body portion 923 in the mold is on the side opposite to the output side from the intermediate position in the motor axial direction S. The ring gate G is disposed on the end 923b side of S2. For this reason, as shown in FIG. 6B, in the gear member 92, the ring gate cutting portion is located on the end portion 923b side on the counter-output side S2 from the intermediate position in the motor axial direction S of the outer peripheral surface 923r of the trunk portion 923. There is G0.

  Accordingly, in this embodiment, as in the first embodiment, the ring gate cutting portion G0 does not remain on the gear portion 926 and the inner peripheral surface 923p, so that the ring gate is used for the operation of the gear train 6 and the friction mechanism 9 using the gear member 92. The same effects as those of the first embodiment are obtained, such as the cutting part G0 does not hinder.

[Embodiment 4]
FIG. 7 is an explanatory diagram of the gear member 92 used in the friction mechanism 9 of the geared motor 1 according to the fourth embodiment of the present invention. FIGS. 7 (a), (b), (c), and (d) They are a plan view, a side view, an exploded perspective view, and a cross-sectional view, as seen from the output side S1, of the gear member 92, respectively.

  The gear member 92 shown in FIG. 7 is also a resin molded product such as PBT as in the first embodiment. In this embodiment, when the gear member 92 is formed, as shown in FIG. 7 (d), the ring gate G is disposed in a portion where the end surface 922 of the output side S1 of the body 923 is formed in the mold. Therefore, as shown in FIG. 7A, in the gear member 92, the ring gate cutting portion G0 is provided on the end surface 922 on the output side S1 of the trunk portion 923.

  Accordingly, in this embodiment, as in the first embodiment, the ring gate cutting portion G0 does not remain on the gear portion 926 and the inner peripheral surface 923p, so that the ring gate is used for the operation of the gear train 6 and the friction mechanism 9 using the gear member 92. The same effects as those of the first embodiment are obtained, such as the cutting part G0 does not hinder.

[Other embodiments]
In the above embodiment, the elastic deformation portion 915 of the rotating member 91 is in contact with the inner peripheral surface 923p of the trunk portion 923 of the gear member 92, but the elasticity of the rotating member 91 is in contact with the outer peripheral surface 923r of the trunk portion 923 of the gear member 92. A configuration in which the deformable portion 915 is in contact may be employed. In this case, “one peripheral surface” in the present invention is “outer peripheral surface 923r”, and “the other peripheral surface” is “inner peripheral surface 923p”.

  In the above embodiment, the gear portion 926 is formed at the output side S1 end portion 923a of the body portion 923 of the gear member 92. However, the end portion 923b on the counter-output side S2 of the body portion 923 of the gear member 92 is formed. A gear portion 926 may be formed on the top. In this case, “one side in the motor axial direction S” in the present invention is “the opposite side S2”, and “the other side in the motor axial direction S” is “the output side S1”.

  In the above embodiment, the friction mechanism 9 is provided on the gear 62, but the friction mechanism 9 may be provided on the other gears 61, 63, 64, 65.

DESCRIPTION OF SYMBOLS 1 Geared motor 2 Motor part 3 Rotor 4 Stator 6 Gear train 9 Friction mechanism 91 Rotating member 92 Gear member 93 Biasing member 651 Output shaft (output member)
915 Elastic deformation portion 921 Fitting hole 922 Output side end surface 923 Body portion 923a Output side end portion 923b Counter output side end portion 923p Body portion inner peripheral surface 923r Body portion outer peripheral surface 924 First annular end surface 925 Second annular end surface End face 925e Edge G of second annular end face Ring gate G0 Ring gate cutting part

Claims (12)

A gear member in which a gear portion is formed on a cylindrical trunk portion extending in the axial direction;
A rotating member provided with a plurality of elastically deforming portions that elastically contact one of the outer surface and the inner surface of the body portion from the radial direction;
Have
The gear mechanism is made of resin, and has a ring gate cutting portion at a position excluding the gear portion and the one peripheral surface. The gear portion is provided at one end of the trunk portion in the axial direction,
The friction mechanism according to claim 1, wherein the ring gate cutting portion is located on the other end side in the axial direction from the gear portion in the trunk portion.   3. The friction mechanism according to claim 2, wherein the ring gate cutting portion is located on the other end portion side of the barrel portion from the intermediate position in the axial direction.   4. The friction mechanism according to claim 2, wherein the ring gate cutting portion is provided on an annular end surface facing the other side in the axial direction in the trunk portion. 5. The barrel includes a first annular end face facing the other side in the axial direction, and a second annular end face facing the other side in the axial direction on one side in the axial direction from the first annular end face,
The friction mechanism according to any one of claims 2 to 4, wherein the ring gate cutting portion is provided on the second annular end surface.   The friction mechanism according to claim 5, wherein the first annular end surface overlaps the rotating member in the axial direction to position the rotating member on one side in the axial direction.   4. The friction mechanism according to claim 2, wherein the ring gate cutting portion is provided at an edge of an annular end surface facing the other side in the axial direction in the trunk portion. 5.   4. The friction mechanism according to claim 2, wherein the ring gate cutting portion is provided on the other peripheral surface of the outer side and the inner side of the body portion. The body includes a first body, and a second body formed on one side in the axial direction from the first body and having an outer diameter larger than that of the first body. The friction mechanism according to any one of claims 1 to 8, wherein the gear portion is formed on the other peripheral surface of the outer side and the inner side of the portion.   10. The biasing member according to claim 1, further comprising a biasing member that biases the elastic deformation portion in a radial direction and elastically contacts the elastic deformation portion with the one peripheral surface. Friction mechanism.   The friction mechanism according to claim 10, wherein the urging member is disposed at a position overlapping the gear portion when viewed from a radial direction. A geared motor comprising the friction mechanism according to any one of claims 1 to 11,
A motor section;
An output member;
A gear train for transmitting rotation of the motor to the output member;
Have
One of the two gears included in the gear train is the gear member, and the other is the rotating member.

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