JP2008215549A - Gear, gear manufacturing method and geared motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a gear which can raise the rotating torque strength of a rotating shaft and a wheel gear without increasing the outer diameter of a shaft material, a gear manufacturing method and a geared motor equipped with the gear. <P>SOLUTION: The gear 10 is equipped with a steel-made rotating shaft 22, gear fixing members 30, 31 provided to rotate coaxially or integrally with the rotating shaft 22 and having the uneven face 32 on the outer circumferential part extended to the radially outer direction beyond the circumferential face of the rotating shaft 22 and a wheel gear 20 made of a resin material and fixed coaxially with the gear fixing members 30, 31 in the state of burying the uneven face 32 of the gear fixing members 30, 31. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a gear gear configured by coaxially fixing a resin wheel gear to a metal rotating shaft, a gear gear manufacturing method, and a geared motor to which the gear gear is applied.

A technique is known in which a wheel gear constituting a worm reduction mechanism is integrally formed at one end portion of a metal rotating shaft by injection molding of a resin material (for example, see Patent Document 1). In this technique, the fixed portion of the wheel gear on the rotating shaft is a protruding portion in which a plurality of protruding portions are formed by cold forging along the axial direction on the outer peripheral surface thereof. And the fixing strength at which the wheel gear does not rotate relative to each other).
JP 2001-65666 A

  However, in the conventional technology as described above, the protrusion formed on the fixed portion of the rotating shaft is formed between the concave portions formed in the circumferential direction on the outer periphery of the shaft material, and therefore, the outermost peripheral portion thereof. The position (distance from the axis of the rotating shaft) is limited by the outer diameter of the shaft material, and it is difficult to form the protrusions beyond the surface of the shaft material.

  Moreover, in order to make the ridge protruding outward in the radial direction from the outer diameter of the rotating shaft, a ridge is formed using a shaft material having a large outer diameter, and a portion other than the ridge is cut or the like. However, in this case, there is a problem that the shaft material becomes expensive and the material yield deteriorates due to the use of cutting.

  In view of the above facts, the present invention provides a gear gear and a gear gear manufacturing method capable of improving the rotational torque strength between the rotating shaft and the wheel gear without relying on increasing the outer diameter of the shaft material. Is the purpose. Another object of the present invention is to provide a geared motor having the gear gear.

  A gear gear according to a first aspect of the present invention is attached to a metal rotation shaft and the rotation shaft so as to rotate coaxially and integrally, and projects outward in the radial direction from the outer peripheral surface of the rotation shaft. A gear fixing member having a concave and convex surface on the outer periphery, and a wheel gear made of a resin material and fixed coaxially to the gear fixing member in a state where at least the concave and convex surface of the gear fixing member is embedded. It is equipped with.

  According to the first aspect of the present invention, at least a part of the torque is transmitted between the metal rotating shaft and the resin wheel gear via the gear fixing member. Here, an uneven surface is formed on the outer peripheral portion of the gear fixing member that protrudes radially outward from the outer peripheral surface of the rotating shaft, and a portion including the uneven surface of the gear fixing member is embedded in the wheel gear. In other words, since the resin material has entered the recess (between the convex portions) located away from the outer peripheral surface of the rotation shaft from the axis of the rotation shaft, the rotation shaft and the wheel gear are rotated greatly. They can be connected with torque strength (fixing strength at which the rotating shaft and the wheel gear do not rotate relative to each other). In this gear gear, since the concave and convex surfaces are formed on the gear fixing member which is a member different from the rotating shaft, the rotational torque strength can be improved without increasing the material diameter of the rotating shaft.

  Thus, in the gear gear according to the first aspect, the rotational torque strength between the rotating shaft and the wheel gear can be improved without relying on increasing the outer diameter of the shaft material.

  A gear gear according to a second aspect of the present invention is the gear gear according to the first aspect, wherein the rotating shaft has a gear fixing portion provided at a portion to which the wheel gear is fixed in the axial direction. The fixing member is fixed to the gear fixing portion of the rotating shaft, and the wheel gear is provided on a disk-shaped gear portion having gear teeth formed on the periphery thereof and an axial center portion of the gear portion. A fixed portion and a boss portion formed and fixed to the rotary shaft in a state where the gear fixing member is embedded are configured.

  According to a second aspect of the present invention, the gear fixing member is fixed to the gear fixing portion of the rotating shaft, and the gear fixing portion and the gear fixing member are embedded in the boss portion of the wheel gear. That is, the wheel gear and the rotating shaft are fixed so as to transmit torque directly and via the gear fixing member. Thereby, in this gear gearwheel, the rotational torque intensity | strength of a rotating shaft and a wheel gear can be improved further.

  A gear gear according to a third aspect of the present invention is the gear gear according to the second aspect, wherein the plurality of gear fixing members are fixed to the gear fixing portion of the rotating shaft, and the boss portion of the wheel gear is The gear fixing portion and the plurality of gear fixing members are embedded.

  In the gear gear according to claim 3, since the plurality of gear fixing members are fixed to the gear fixing portion of the rotating shaft, the individual gear fixing members can be downsized (smaller diameter, thinner), or the rotational torque strength can be reduced. Can be adjusted as required.

  A gear gear according to a fourth aspect of the present invention is the gear gear according to the third aspect, wherein at least a pair of gear fixing members adjacent to each other in the axial direction of the rotating shaft among the plurality of gear fixing members have the same pitch. The concave and convex surfaces are formed, and the concave and convex surfaces are shifted in the circumferential direction as viewed from the axial direction of the rotating shaft and fixed to the gear fixing portion.

  According to a fourth aspect of the present invention, at least one pair (two) of the gear fixing members among a pair or a plurality of pairs of gear fixing members adjacent to each other in the axial direction of the rotating shaft has an uneven surface pitch (convex in the circumferential direction). The distance between the projections of the other gear fixing member is the same as that between the projections of the one gear fixing member. Is facing. For this reason, it functions as an increase in the torque transmission portion (unevenness) between the gear fixing member (rotary shaft) and the wheel gear in the circumferential direction of the rotational shaft, thereby further increasing the rotational torque strength between the rotational shaft and the wheel gear. Can be improved.

  A gear gear according to a fifth aspect of the present invention is the gear gear according to the third or fourth aspect, wherein at least some of the plurality of gear fixing members are used for the other gear fixing. It is spaced apart from the member in the axial direction of the rotary shaft.

  In the gear gear according to claim 5, since at least a part of the plurality of gear fixing members is fixed to the gear fixing portion of the rotating shaft in a state of being separated in the axial direction of the rotating shaft, the boss portion of the wheel gear (resin The contact area between the material and the gear fixing member is increased, and the rotational torque strength between the rotating shaft and the wheel gear can be further improved.

  A gear gear according to a sixth aspect of the present invention is the gear gear according to the fifth aspect, wherein the gear portion of the wheel gear has an arc-shaped tooth bottom shape having a smaller diameter at the center than both ends in the axial direction. In the axial direction of the rotary shaft, the minimum diameter portion of the gear portion is disposed between the plurality of gear fixing members spaced apart in the axial direction of the rotary shaft.

  According to a sixth aspect of the present invention, the minimum diameter portion of the central portion in the axial direction (thickness), which is the meshing portion of the gear portion of the wheel gear with the counterpart gear, is a plurality of gears in the axial direction of the rotating shaft. Since it is arrange | positioned in the clearance gap between the fixing members, it is suppressed that the roundness of a minimum diameter part receives the influence of the uneven surface of a gear fixing member in the case of shaping | molding of a gear part.

  According to a seventh aspect of the present invention, there is provided a gear gear manufacturing method for fixing a plurality of gears, wherein each of the gear fixing portions of a metal rotating shaft has a larger diameter than the rotating shaft and has an uneven surface on an outer peripheral surface. A member fixing step for fixing the member apart in the axial direction of the rotating shaft, and a gear fixing portion of the rotating shaft by injection molding of a resin material using the rotating shaft to which the gear fixing member is fixed as an insert material And a molding step of integrally molding the wheel gear in which each of the plurality of gear fixing members is embedded on the rotating shaft.

  In the gear gear manufacturing method according to the seventh aspect, in the member fixing step, a plurality of gear fixing members are fixed to the gear fixing portion of the rotating shaft while being separated in the axial direction of the rotating shaft. As a result, each gear fixing member is fixed so as to rotate coaxially and integrally with the rotation shaft so that the uneven surface protrudes radially outward from the outer peripheral surface of the rotation shaft. Further, in the molding process, for example, a rotating shaft having a plurality of gear fixing members fixed to the gear fixing portion is set in a mold, the mold is filled with a resin material, and the resin material is cured, so that the rotating shaft is The wheel gear is molded integrally.

  Here, in the manufacturing method of the gear gear, a plurality of gear fixing members having convex and concave surfaces formed on the outer peripheral portion projecting radially outward from the outer peripheral surface of the rotary shaft are combined with the wheel gear together with the gear fixing portion of the rotary shaft. In other words, between the convex and concave portions of the gear fixing member and the plurality of gear fixing members that are spaced radially outward from the outer peripheral surface of the rotating shaft from the shaft center of the rotating shaft. Therefore, the rotating shaft and the wheel gear can be coupled with a large rotational torque strength (adhesion strength at which the rotating shaft and the wheel gear do not rotate relative to each other). And since the uneven surface was formed in each gear fixing member different from a rotating shaft, it is possible to improve rotational torque intensity, without making the raw material diameter of a rotating shaft thick.

  Thus, in the gear gear manufacturing method according to the seventh aspect, the rotational torque strength between the rotating shaft and the wheel gear can be improved without relying on increasing the outer diameter of the shaft material.

  A gear gear manufacturing method according to an eighth aspect of the present invention is the gear gear manufacturing method according to the seventh aspect, wherein in the member fixing step, of the plurality of gear fixing members, adjacent to the axial direction of the rotary shaft. The at least one pair of gear fixing members that match each other are formed so that the uneven surfaces are formed at the same pitch, and the respective uneven surfaces are shifted in the circumferential direction when viewed from the axial direction of the rotating shaft. Fix it to the gear fixing part of the shaft.

  In the gear gear manufacturing method according to claim 8, in the member fixing step, at least a pair (two) of the gear fixing members among a pair or a plurality of pairs of the gear fixing members adjacent in the axial direction of the rotation shaft are uneven. Rotate so that the surface pitch (space between convex parts in the circumferential direction, etc.) is the same, and the convex part of the other gear fixing member faces between the convex parts of one gear fixing member. The shafts are displaced from each other in the circumferential direction as viewed from the axial direction of the shaft and fixed to the gear fixing portion of the rotating shaft. As a result, the torque transmitting portion (unevenness) between the gear fixing member (rotating shaft) and the wheel gear in the circumferential direction of the rotating shaft functions as an increase, and the rotational torque strength between the rotating shaft and the wheel gear is further improved. can do.

  A gear gear manufacturing method according to a ninth aspect of the present invention is the gear gear manufacturing method according to the seventh or eighth aspect, wherein the gear portion of the wheel gear has a smaller diameter on the center side than both ends in the axial direction. The plurality of gears fixed to each other, wherein the smallest diameter portion of the gear portion is spaced apart in the axial direction of the rotating shaft in the axial direction of the rotating shaft in the member fixing step The plurality of gear fixing members are fixed to the gear fixing portion of the rotating shaft so as to be positioned between the members.

  In the gear gear manufacturing method according to claim 9, in the member fixing step, the minimum diameter portion at the center in the axis (thickness) direction which is a meshing portion (main part) of the gear portion of the wheel gear with the counterpart gear is a rotating shaft. Are arranged in the gaps between the plurality of gear fixing members in the axial direction, so that the roundness of the minimum diameter portion is suppressed from being affected by the uneven surface of the gear fixing member when the gear portion is formed. The

  The geared motor according to the invention of claim 10 is applied as a motor part, a worm rotated around its own axis by the operation of the motor part, and a worm wheel meshed with the worm wheel. A gear gear according to any one of claims 1 to 6, or a gear gear manufactured by the method for manufacturing a gear gear according to any one of claims 7 to 9.

  In the geared geared motor of claim 10, for example, the driving force (torque) of the motor unit is transmitted to the rotating shaft of the gear gear while being decelerated (torque amplification) via the worm and worm wheel (wheel gear). The Here, the geared motor uses a gear gear according to any one of claims 1 to 6 or a wheel gear of a gear gear manufactured by the method for manufacturing a gear gear according to claims 7 to 9 as a worm wheel. Therefore, sufficient rotational torque strength can be ensured.

  A gear gear 10 according to an embodiment of the present invention will be described with reference to FIGS. 1 to 5. First, a schematic overall configuration of the geared motor 12 to which the gear gear 10 is applied will be described, then a detailed configuration of the gear gear 10 will be described, and then a manufacturing method of the gear gear 10 will be described.

(General outline of geared motor)
FIG. 5 shows a schematic perspective view in which the entire configuration of the geared motor 12 according to the embodiment of the present invention is partially broken. As shown in this figure, the geared motor 12 has a configuration in which a motor portion 12A and a gear mechanism portion 12B are integrally provided. The motor unit 12A accommodates an armature (not shown), and a worm 14 is coaxially and integrally rotated at the distal end side of the rotation shaft of the armature. The worm 14 enters the housing 16 of the gear mechanism portion 12B and meshes with a worm wheel 24 (described later) constituting the gear gear 10. The geared motor 12 constitutes a worm reduction mechanism (worm gear) 18 with the worm wheel 24.

  A gear gear 10 is disposed in the gear mechanism 12 </ b> B of the geared motor 12. The gear gear 10 has a structure in which a wheel gear 20 made of a resin material is fixed to a rotating shaft 22 that is a metal output shaft by integral molding. In the gear gear 10, the wheel gear 20 is accommodated in the housing 16 of the gear mechanism portion 12 </ b> B, and a part of the rotating shaft 22 in the axial direction protrudes from the housing 16 to the outside. A tip 22A of the rotating shaft 22 protruding outside the housing 16 is connected to a driven device (load) so that power can be transmitted.

  The wheel gear 20 of the gear gear 10 is engaged with the worm 14 described above in the housing 16 to form a worm reduction mechanism 18 and a worm wheel portion 24 as a disc-shaped gear portion, and an axial center portion of the worm wheel 24. The boss portion 26 fixed to the rotating shaft 22 is configured as a main portion. Therefore, in the geared motor 12, when the motor unit 12A is driven, the rotation (torque) of the motor unit 12A is transmitted to the rotating shaft 22 while being decelerated (torque amplification) via the worm decelerating mechanism 18, and the gear unit 12A The wheel gear 20 and the rotary shaft 22 of the gear 10 are configured to rotate integrally.

  The geared motor 12 is applied to various applications, for example, as a wiper motor as a drive source of the wiper device, a power window motor as a drive source of the power window device, and the like.

(Detailed configuration of gear gear)
As shown in FIG. 2, which is a partially enlarged view of FIGS. 1 and 1, the boss portion 26 of the wheel gear 20, while burying a gear fixing portion 28 set on one end side in the axial direction of the rotating shaft 22, It is fixed to the part 26. In the gear gear 10, gear fixing members 30 and 31 fixed to the gear fixing portion 28 are embedded in the boss portion 26 of the wheel gear 20 together with the gear fixing portion 28 of the rotating shaft 22. This will be specifically described below.

  In this embodiment, the gear fixing portion 28 of the rotating shaft 22 is configured by knurling the outer peripheral surface (surface) of the rotating shaft 22 as shown in FIG. As shown in FIGS. 3B and 4, the gear fixing members 30 and 31 are made of a metal material, and the inner diameter corresponds to the outer diameter of the gear fixing portion 28 (the rotating shaft 22), and the outer diameter is the rotating shaft. 22 is formed in an annular shape that is sufficiently larger than the outer diameter of 22, and a convex / concave surface 32 in which convex portions 32 </ b> A and concave portions 32 </ b> B are alternately arranged at equal pitches in the circumferential direction is formed on the outer peripheral portion. ing.

  The gear fixing members 30 and 31 are press-fitted in the fitting holes 30A and 31A (see FIG. 2) formed in the shaft center portion, so that the gear fixing members 28 and the gear fixing portion 28 are relatively rotated at a torque equal to or less than a predetermined value. It is fixed not to. Therefore, as shown in FIG. 4, the uneven surfaces 32 of the gear fixing members 30, 31 protrude outward in the radial direction from the outer peripheral surface of the rotating shaft 22 (separate in the radial direction from the axis of the rotating shaft 22). positioned.

  In the gear gear 10, a plurality (two in this embodiment) of gear fixing members 30 and 31 are press-fitted and fixed to the gear fixing portion 28 of the rotating shaft 22. As shown in FIGS. 3B and 4, the pair of gear fixing members 30 and 31 adjacent to each other in the axial direction of the rotating shaft 22 have substantially the same size and shape (the uneven surface 32 having the same size and shape is formed). And the convex portion 32A (concave portion 32B) of the other gear fixing member 31 is positioned between the convex portions 32A (concave portion 32B) of the one gear fixing member 30 when viewed from the axial direction of the rotary shaft 22. Further, the convex and concave surfaces 32 are fixed to the gear fixing portion 28 in a state where the convex and concave surfaces 32 are shifted in the circumferential direction.

  Further, in the gear gear 10, the above-described two gear fixing members 30 and 31 are arranged apart from each other in the axial direction of the rotary shaft 22. The positions of these two gear fixing members 30 and 31 in the axial direction of the rotating shaft 22 will be described later.

  As described above, the boss portion 26 of the wheel gear 20 is fixed to one end portion of the rotating shaft 22 by embedding the gear fixing portion 28 and the plurality of gear fixing members 30 and 31. Although details will be described later, the wheel gear 20 is formed by injection molding in which a mold is filled with a resin material in a state where the rotary shaft 22 to which the gear fixing member 30 is fixed is set in the mold (the rotary shaft 22 is an insert material). The gear fixing portion 28 and the gear fixing member 30 are attached to the boss portion 26 so that the resin material is brought into contact with the surfaces of the gear fixing portion 28 and the gear fixing members 30 and 31. It is buried.

  In this embodiment, the boss portion 26 is formed thicker in the axial direction than the worm wheel portion 24, and also wraps around the end surface 22 </ b> B on the gear fixing portion 28 side of the rotating shaft 22 to cover the end surface 22 </ b> B. . On the other hand, the worm wheel portion 24 is integrally extended radially outward from a substantially central portion in the axial direction of the outer peripheral portion 26A of the boss portion 26, and a tooth portion 34 that meshes with the worm 14 is formed on the outer peripheral portion 24A. Yes.

  As shown in FIG. 1, each tooth 36 constituting the tooth portion 34 has a bottom (tooth bottom) 36 </ b> A that is concave outward in the radial direction of the worm wheel portion 24 (opens radially outward). It is formed in a substantially arc shape. In this embodiment, the tooth tip 36B of each tooth 36 is also concentric with the tooth bottom 36A.

  Therefore, the worm wheel portion 24 is configured such that the diameter on the center side in the thickness direction is smaller than the diameter on both ends, and the center portion in the thickness direction is the minimum diameter portion 24B. The minimum diameter portion 24 </ b> B of the worm wheel portion 24 is located within the set range of the gap d between the pair of gear fixing members 30 and 31 in the axial direction of the rotating shaft 22. In this embodiment, the minimum diameter portion 24 </ b> B is located at a substantially central portion of the gap d between the pair of gear fixing members 30 and 31 in the axial direction of the rotating shaft 22.

  In other words, the two gear fixing members 30 and 31 adjacent to each other in the axial direction of the rotating shaft 22 are formed with the worm wheel portion 24 so that the minimum diameter portion 24B of the worm wheel portion 24 is located in the gap d between each other. Before, it is fixed to the gear fixing part 28 of the rotating shaft 22. More specifically, for example, the gear fixing member 30 that is first fixed to the gear fixing portion 28 is press-fitted (inserted) to a predetermined position in the axial direction of the rotary shaft 22 and is fixed (positioned by a step portion or the like). Then, the gear fixing member 31 fixed to the gear fixing portion 28 is then press-fitted into the gear fixing portion 28 until the distance from the previously fixed gear fixing member 30 reaches a set value. Thus, the minimum diameter portion 24B of the worm wheel portion 24 can be positioned in the gap d.

  In this embodiment, the worm wheel portion 24 has an outer peripheral portion 24A in which the tooth portion 34 is formed thicker than the connecting portion 24C that connects the outer peripheral portion 24A and the boss portion 26. The outer peripheral portion 24A is thickened on both sides in the axial direction of the connecting portion 24C. As shown in FIG. 1, the virtual orthogonal cross section S with the rotary shaft 22 passing through the minimum diameter portion 24B has the connecting portion 24C. It is supposed to pass. In other words, the minimum diameter portion 24B of the worm wheel portion 24 is configured to be filled (continuously) with the resin material in the radial direction from the tooth bottom 36A to the gear fixing member 30 of the rotating shaft 22.

(Gear gear manufacturing method)
In manufacturing the gear gear 10 having the above-described configuration, first, the first gear fixing member 30 is press-fitted into the gear fixing portion 28 of the rotary shaft 22 to a predetermined position in the axial direction of the rotary shaft 22, so that the rotary shaft 22 is pressed. It fixes to the gear fixing part 28 of this. Next, with respect to the first gear fixing member 30, the second gear fixing member 31 is positioned such that the convex portion 32A is positioned between the convex portions 32A of the convex and concave surface 32 of the first gear fixing member 30. (See FIG. 3 (B)), and press-fit into the gear fixing portion 28 and fixed so that the axial distance of the rotating shaft 22 becomes a predetermined distance (see FIG. 3 (A)).

  As a result, as shown in FIGS. 3A and 4, a gap d is formed in the axial direction of the rotary shaft 22 between the two gear fixing members 30 and 31. The above process is a gear fixing member fixing step corresponding to the member fixing step in the present invention.

  Next, in the molding step (molding preparation step), the rotary shaft 22 on which the two gear fixing members 30, 31 are fixed in the gear fixing member fixing step is set in a mold (not shown). Then, a resin material is filled in a mold in which the rotating shaft 22 to which the two gear fixing members 30 and 31 are fixed is set and cured. The wheel gear 20 is formed integrally with the rotating shaft 22 by the curing of the resin material. By taking out the wheel gear 20 from the mold, the wheel gear 20 in which each of the gear fixing portion 28 and the two gear fixing members 30 and 31 is embedded in the boss portion 26 is formed at one end of the rotating shaft 22. Is done. This process is a molding process. And the manufacture of the gear 10 is completed by finishing as needed.

  Next, the operation of the present embodiment will be described.

  In the geared motor 12 to which the gear gear 10 having the above-described configuration is applied, when the geared motor 12 is driven, the worm 14 of the gear mechanism 12B is rotated around its own axis and is engaged with the worm 14. Is driven to rotate around its own axis. Since the worm wheel portion 24 constituting the gear portion of the wheel gear 20 is fixed to the rotating shaft 22 via the boss portion 26 constituting the axial center portion of the wheel gear 20, the rotating shaft 22 is connected to the worm wheel portion. 24, the speed of the worm 14 is reduced or rotated at the rotational speed.

  Here, in the gear gear 10, since the gear fixing members 30 and 31 are fixed to the gear fixing portion 28 that is the fixing portion of the rotating shaft 22 with the wheel gear 20, the gear gear 10 is more radial than the outer peripheral surface of the rotating shaft 22. The uneven surface 32 can be arranged outside. For this reason, in the gear gear 10, relative rotation exceeding the allowable value between the rotation shaft 22 and the wheel gear 20 is not caused as compared with a configuration in which a convex / concave surface embedded in the boss portion is formed on the peripheral surface of the rotation shaft 22. The rotational torque intensity that can be grasped as the limit torque can be increased.

  Thereby, the rotating shaft 22 can be formed of the shaft material having the same diameter as the outer diameter of the rotating shaft 22, and the rotating shaft 22 and the wheel gear 20 can be fixed with a large rotational torque strength. That is, by providing the convex and concave surfaces 32 by projecting outwardly in the radial direction from the outer peripheral surface of the rotating shaft 22 by the gear fixing members 30 and 31, without depending on using a shaft material having a diameter larger than that of the rotating shaft 22. Thus, it is possible to obtain a gear gear 10 that is inexpensive and has sufficient rotational torque strength.

  Further, in the gear gear 10, since the plurality of gear fixing members 30, 31 are respectively fixed to the gear fixing portion 28, the degree of freedom in design is improved. For example, in the gear 10, the gear fixing members 30, 31 are downsized (gear fixing members 30, 31 themselves or irregularities) as compared with a configuration that meets the rotational torque strength required by one gear fixing member 30. The diameter of the surface 32 can be reduced, or the gear fixing members 30 and 31 can be thinned.

  Thereby, for example, the thickness of the gear fixing members 30 and 31 is set as a thickness with good workability, or the outer diameter of the gear fixing members 30 and 31 and the dimensional shape of the uneven surface 32 are formed into the wheel gear 20. It is possible to set as a dimensional shape having a small influence on the property. Further, for example, in the gear gear 10, the substantial length in the axial direction of the gear fixing member 30 (convex / concave surface 32) is variable according to the number of gear fixing members 30 (gear fixing members 31). Therefore, the rotational torque intensity can be adjusted according to the required value.

  Further, in the gear gear 10, since the convex and concave surfaces 32 of the gear fixing members 30 and 31 adjacent to each other in the axial direction of the rotary shaft 22 are shifted in the circumferential direction, in other words, when viewed from the axial direction of the rotary shaft 22. Since the convex portion 32A of the other gear fixing member 31 is positioned between the convex portions 32A of one gear fixing member 30, the resin material constituting the boss portion 26 is composed of two gear fixing members. The two gear fixing members 30 can be embedded so as to be entangled with 30. Thereby, in the gear gear 10, compared with the structure (structure included in the present invention) in which the uneven surfaces 32 of the gear fixing members 30, 31 adjacent to each other in the axial direction of the rotating shaft 22 are matched, the rotational torque strength is increased. Can be improved.

  Furthermore, in the gear gear 10, since the two gear fixing members 30 and 31 are separated in the axial direction of the rotary shaft 22, the boss portion 26 is provided in the gap d between the two gear fixing members 30 and 31. The constituent resin material goes around. For this reason, since the two gear fixing members 30 and 31 are in contact with the resin material on both the uneven surface 32 and the thickness direction, the two gear fixing members 30 and 31 are overlapped in the axial direction of the rotary shaft 22. The rotational torque strength can be improved as compared to the configuration that is included (the configuration included in the present invention).

  As described above, in the gear gear 10, the convex and concave surfaces 32 of the gear fixing members 30 and 31 adjacent to each other in the axial direction of the rotating shaft 22 are made coincide with each other in the circumferential direction, and the two gear fixing members 30 and 31 are in the axial direction of 22. In comparison with a comparative example (a configuration included in the present invention, which can be grasped as a configuration using a single gear fixing member 30 having a thickness twice). It has been experimentally confirmed that the torque intensity is improved. In this experiment, the gear gear 10 has an approximately 8% improvement in rotational torque strength over the comparative example described above.

  Moreover, in the gear gear 10, the minimum diameter portion 24 </ b> B of the worm wheel portion 24 constituting the wheel gear 20 is positioned within the gap d between the two gear fixing members 30 and 31 in the axial direction of the rotating shaft 22. Therefore, the roundness of the minimum diameter portion 24B is suppressed from being affected by the uneven surface 32. Supplementally, in the wheel gear 20, by providing a non-circular uneven surface 32 on the outer peripheral portion of the gear fixing members 30, 31, a difference in shrinkage (amount) at the time of resin curing in the circumferential direction of the worm wheel portion 24. Although it is easy to occur, the required accuracy of the roundness at the minimum diameter portion 24B can be ensured by arranging the concave / convex surface 32 on the radially inner side of the minimum diameter portion 24B. Accordingly, in the configuration in which the non-circular and relatively large-diameter gear fixing members 30 and 31 are embedded in the boss portion 26 to improve the rotational torque strength, the worm wheel portion 24 meshes with the worm 14 ( It is possible to ensure the dimensional accuracy of the main part.

  Further, since the gear gear 10 has a structure in which the gear fixing members 30 and 31 which are separate members are fixed to the rotating shaft 22, the material and processing method are determined by the rotating shaft 22 and the gear fixing members 30 and 31. In addition, the degree of freedom in design can be improved by making it possible to vary the heat treatment (presence or absence). Therefore, for example, while the gear fixing members 30 and 31 are formed by pressing a metal plate material, the gear fixing portion 28 of the rotating shaft 22 is formed by forging, or the gear fixing portion 28 is subjected to heat treatment. be able to.

  Further, in the gear gear 10, the gear fixing members 30, 31 fixed to the rotary shaft 22 project radially outward from the outer peripheral surface of the rotary shaft 22. Misalignment in the direction is prevented. That is, the fixing strength in the axial direction of the wheel gear 20 with respect to the rotating shaft 22 can also be improved.

  Thus, in the gear gear 10 and the manufacturing method of the gear gear 10 according to the embodiment of the present invention, the rotational torque strength between the rotating shaft and the wheel gear is improved without relying on increasing the outer diameter of the shaft material. be able to.

  Further, in the geared motor 12 to which the gear gear 10 is applied, the worm wheel portion 24 constituting the worm reduction mechanism 18 having a large reduction ratio, that is, a torque amplification ratio, is fixed to the rotary shaft 22 via the boss portion 26, and the wheel gear 20. That is, since the gear gear 10 according to the present invention is applied to a portion where a large torque acts, a required rotational torque strength can be ensured. And the geared gear 10 is applied, whereby the geared motor 12 can be configured inexpensively and compactly while ensuring a required rotational torque.

  In the above-described embodiment, the example in which the gear fixing members 30 and 31 of the gear gear 10 are respectively positioned with respect to the gear fixing portion 28 of the rotating shaft 22 has been shown, but the present invention is not limited to this. It is good also as a structure provided with the spacer part for maintaining the space | interval between the gear fixing members 30 and 31 adjacent to the axial direction of the rotating shaft 22. FIG. Specifically, for example, as shown in FIG. 6, the spacer portion 40 may be integrally formed on one gear fixing member 30 (or the gear fixing member 31) adjacent in the axial direction of the rotating shaft 22. Further, as shown in FIG. 7, for example, a configuration may be adopted in which spacer portions 42 are integrally formed on each of the gear fixing members 30, 31 adjacent to each other in the axial direction of the rotary shaft 22, and further, for example, as shown in FIG. As described above, the spacer portion 44, which is a separate member independent of the gear fixing members 30, 31, may be sandwiched between the gear fixing members 30, 31 adjacent in the axial direction of the rotating shaft 22.

  Moreover, although the wheel gear 20 which comprises the gear gearwheel 10 showed the example which has the worm wheel part 24 as a gear part in the said embodiment, this invention is not limited to this, For example, the wheel gear 20 is a worm wheel. Instead of the portion 24, a spur gear, a hypoid gear, or the like may be provided.

  Furthermore, in the said embodiment, although the gear gearwheel 10 was shown applied to the geared motor 12, this invention is not limited to this, For example, the gear gearwheel 10 is applied to a reduction gear device or a power transmission device. Also good. Therefore, the present invention is not limited to the configuration in which the wheel gear 20 is fixed to one end portion in the axial direction of the rotating shaft 22. For example, the wheel gear 20 is integrally formed at a portion other than both axial ends of the rotating shaft 22. May be.

  Furthermore, in the above-described embodiment, an example in which the gear fixing members 30 and 31 are made of metal is shown. However, the present invention is not limited to this. For example, the gear fixing members 30 and 31 are formed before the wheel gear 20 is molded. It is also possible to use a resin that is molded.

  Furthermore, in the above-described embodiment, the example in which the plurality of gear fixing members 30 and 31 have the same dimensional shape (having the uneven surface 32) is shown, but the present invention is not limited to this, for example, the dimension A plurality of gear fixing members 30, 31 having different shapes may be fixed to the gear fixing portion 28 and embedded in the boss portion 26.

It is a sectional side view of the gear gear which concerns on embodiment of this invention. It is a sectional side view which expands and shows a part of gear gear which concerns on embodiment of this invention. It is a figure which shows the state which fixed the member for gear fixation to the rotating shaft which comprises the gear gearwheel which concerns on embodiment of this invention, (A) is a side view, (B) is a bottom view. It is a perspective view of the state where the member for gear fixation was fixed to the rotating shaft which constitutes the gear gear concerning the embodiment of the present invention. 1 is a partially cutaway perspective view showing a geared motor to which a gear gear according to an embodiment of the present invention is applied. It is a sectional side view which expands and shows a part of gear gear which concerns on the 1st modification of embodiment of this invention. It is a sectional side view which expands and shows a part of gear gear which concerns on the 2nd modification of embodiment of this invention. It is a sectional side view which expands and shows a part of gear gear which concerns on the 3rd modification of embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Gear gear, 12 ... Geared motor, 12A ... Motor part, 14 ... Worm, 20 ... Wheel gear, 22 ... Rotating shaft, 24 ... Worm wheel part (Gear Part), 24B ... minimum diameter part, 26 ... boss part, 28 ... gear fixing part, 30 · 31 ... gear fixing member, 32 ... uneven surface, 36A ... tooth bottom

Claims (10)

A metal rotating shaft,
A gear fixing member attached to the rotary shaft so as to rotate coaxially and integrally, and having a convex and concave surface on an outer peripheral portion projecting radially outward from the outer peripheral surface of the rotary shaft;
A wheel gear made of a resin material and coaxially fixed to the gear fixing member in a state where at least the uneven surface of the gear fixing member is embedded;
Gear gear with. The rotating shaft has a gear fixing portion provided at a portion to which the wheel gear is fixed in the axial direction,
The gear fixing member is fixed to the gear fixing portion of the rotating shaft,
The wheel gear includes the disc-shaped gear portion having gear teeth formed on the periphery thereof, and the rotating shaft in a state where the gear fixing portion and the gear fixing member are embedded in the shaft center portion of the gear portion. The gear gear according to claim 1, comprising a boss portion molded and fixed to. A plurality of the gear fixing members are fixed to the gear fixing portion of the rotating shaft,
The gear gear according to claim 2, wherein the gear fixing portion and the plurality of gear fixing members are embedded in a boss portion of the wheel gear.   Among the plurality of gear fixing members, at least one pair of gear fixing members adjacent to each other in the axial direction of the rotating shaft has the uneven surface formed at the same pitch, and each other as viewed from the axial direction of the rotating shaft. The gear gear according to claim 3, wherein the uneven surface is displaced in the circumferential direction and is fixed to the gear fixing portion.   5. The gear gear according to claim 3, wherein at least some of the plurality of gear fixing members are spaced apart from other gear fixing members in the axial direction of the rotation shaft. . The gear portion of the wheel gear has an arc-shaped tooth bottom shape having a smaller diameter at the center than both ends in the axial direction,
The gear gear according to claim 5, wherein a minimum diameter portion of the gear portion is disposed between the plurality of gear fixing members spaced apart in the axial direction of the rotary shaft in the axial direction of the rotary shaft. A plurality of gear fixing members each having a diameter larger than that of the rotating shaft and having an uneven surface on the outer peripheral surface thereof are fixed to the gear fixing portion of the metal rotating shaft while being spaced apart from each other in the axial direction of the rotating shaft. A member fixing step;
The rotating shaft on which the gear fixing member is fixed is used as an insert material, and the wheel gear in which the gear fixing portion of the rotating shaft and each of the plurality of gear fixing members are embedded by injection molding of a resin material is rotated. A molding process for molding integrally with the shaft;
A manufacturing method of a gear gear including the above.   In the member fixing step, among the plurality of gear fixing members, at least a pair of gear fixing members adjacent to each other in the axial direction of the rotation shaft are formed with the uneven surface at the same pitch, and the rotation The method of manufacturing a gear gear according to claim 7, wherein each gear is fixed to a gear fixing portion of the rotary shaft so that the uneven surfaces are shifted in the circumferential direction when viewed from the axial direction of the shaft. The gear portion of the wheel gear has an arc-shaped tooth bottom surface having a smaller diameter on the center side than both ends in the axial direction.
In the member fixing step, in the axial direction of the rotating shaft, the plurality of the gear portions are positioned such that a minimum diameter portion of the gear portion is positioned between the plurality of gear fixing members spaced apart in the axial direction of the rotating shaft. The gear gear manufacturing method according to claim 7 or 8, wherein the gear fixing member is fixed to a gear fixing portion of the rotary shaft. A motor section;
A worm that is rotationally driven around its own axis by the operation of the motor unit;
The gear gear according to any one of claims 1 to 6, or the gear according to any one of claims 7 to 9, wherein the wheel gear is applied as a worm wheel meshed with the worm. A gear gear manufactured by a gear manufacturing method;
Geared motor equipped with.

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