JP2011017368A - Gear reducer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To inhibit creep deformation of a resin gear without enlarging a gear reducer.SOLUTION: A second gear 60 and a spur gear 42 of a first gear 40 composing a gear train of the gear reducer 4B are made of resin. Flexible metal plates K1, K2 are integrally inserted and formed at an inside of each tooth 42A, 64. The metal plates K1, K2 are arranged with plate surface thereof oriented to a tooth surface of each tooth 42A, 64. Each teeth 42A, 64 meshing each other are supported by the metal plates K1, K2. Consequently, a support structure inhibiting creep deformation is provided.

Description

  The present invention relates to a gear reducer. Specifically, the present invention relates to a gear reducer that decelerates and outputs rotational power by transmission of rotational power of a gear train.

  2. Description of the Related Art Conventionally, in a power transmission mechanism using a gear train, each gear constituting the gear train is formed by resin molding for weight reduction. Here, in Patent Document 1 below, each tooth of the gear on one side that meshes with each other is elastically sandwiched between each tooth of the gear on the other side that meshes between these teeth to eliminate backlash. A technique in which a plate spring is disposed is disclosed. In this disclosure, the backlash in the meshing state of both gears is prevented by the clamping force of the plate spring, and this clamping force prevents creep deformation even when the gear on one side is pressed by the gear on the other side. It has become.

JP 2008-189172 A

  However, since the plate springs are arranged side by side in the axial direction with respect to the gear as in the prior art disclosed above, the entire structure is enlarged in the axial direction.

  The present invention has been devised to solve the above-described problems, and the problem to be solved by the present invention is to suppress creep deformation of a resin gear without increasing the size of the gear reducer. There is in doing so.

In order to solve the above problems, the gear reducer of the present invention takes the following means.
A first aspect of the present invention is a gear reducer that decelerates and outputs rotational power by transmitting rotational power of a gear train. At least one gear constituting the gear train is made of resin, and a metal plate having flexibility is insert-molded inside each tooth and formed integrally. The metal plate is arranged so that the plate surface is directed to the tooth surface of each tooth, and is configured to support each tooth that becomes a meshing portion by the metal plate so that it is difficult to be creep-deformed.

  According to the first aspect of the present invention, at least one resin gear constituting the gear train is formed by insert-molding a flexible metal plate inside each tooth, and thereby each Teeth are supported, making it difficult for creep deformation. Thus, by adopting a configuration in which the metal plate is insert-molded inside each tooth of the resin gear, it is possible to suppress the creep deformation of the gear without increasing the configuration of the gear reducer. it can.

  Next, according to a second aspect of the present invention, in the first aspect described above, the metal plate is insert-molded in a bent form so as to be arranged along the tooth profile of each tooth inside each tooth.

  According to the second aspect of the invention, the metal plate is insert-molded in a bent shape so as to be arranged along the tooth profile of each tooth inside each tooth. It can be supported so that creep deformation can be more effectively suppressed.

  Next, according to a third invention, in the first or second invention described above, the metal plate passes along the entire circumference of the gear through the inside of each tooth and the inside of the root portion between each tooth. It is formed as a single metal plate arranged in a connected form.

  According to the third aspect of the present invention, the metal plate passes through the inside of each tooth and the inside of the root portion between each tooth as a single metal plate arranged in a continuous manner over the entire circumference of the gear. By being formed, the creep deformation of each tooth can be more effectively suppressed by the metal plate continuously disposed over the inside of each tooth and the vicinity thereof.

It is the schematic of the vehicle seat provided with the gear reducer of Example 1. FIG. It is a disassembled perspective view of a gear reducer. It is an assembly drawing of a gear reducer. FIG. 4 is a sectional view taken along line IV-IV in FIG. 3. It is an internal structure figure of a gear reducer.

  EMBODIMENT OF THE INVENTION Below, the form for implementing this invention is demonstrated using drawing.

  First, the configuration of the gear reducer 4B according to the first embodiment will be described with reference to FIGS. As shown in FIG. 1, the gear reducer 4B is provided in a vehicle seat, and is electrically connected to the reclining devices 3 and 3 on each side for connecting the seat back to the seat cushion so that the backrest angle can be adjusted. This is a mechanism device for decelerating and outputting the rotational output from the motor 4A. Here, each of the reclining devices 3 and 3 described above is provided by connecting both side portions of the back frame 1 forming the skeleton of the seat back and both side portions of the cushion frame 2 forming the skeleton of the seat cushion. Yes.

  These reclining devices 3 and 3 are normally held in a state in which the backrest angle of the seat back is fixed as a state in which rotation is stopped. The reclining devices 3 and 3 are configured so that the rod 3A inserted through the central portion of the reclining devices 3 and 3 is pivoted by the driving device 4 including the electric motor 4A and the gear reducer 4B. It is designed to rotate so as to change the backrest angle.

  Here, the drive device 4 described above is provided inside the frame of the back frame 1, and is coupled and fixed to a side frame on the left side of the back frame 1 by a support bracket 1A. The support bracket 1A is also integrally coupled to the right side frame in the figure by the reinforcing pipe 1B, and is firmly coupled to both side frames. And the above-mentioned rod 3A which connects reclining device 3,3 is penetrated and provided in the pipe | tube inside of above-mentioned reinforcement pipe 1B, and the outer peripheral part is covered and protected by reinforcement pipe 1B.

  The seat back described above is rotated so that, as the electric motor 4A is driven and rotated, the backrest angle is raised to the front side or tilted to the rear side. The rotational movement of the seat back to the front side or the rear side is caused by the rotation of a stopper piece (not shown) joined to the outer side surface of each side frame of the back frame 1 to the front side or the rear side of the seat back. Thus, the front and rear falling locking surfaces 2A and 2B formed on the cushion frame 2 are brought into contact with each other so as to be locked.

  Hereinafter, the configuration of the gear reducer 4B described above will be described in detail with reference to FIGS. As shown in FIG. 2, the gear reducer 4B includes a resin main body case 10 and a lid case 20, a metal worm 30, a resin first gear 40 and a second gear 60, and a metal. And a rod-like support shaft 50. Here, in the resin main body case 10, the lid case 20, the first gear 40, and the second gear 60 described above, a heat radiation groove M that functions as a heat radiation groove in a portion having a wide surface such as a side surface thereof. · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · ····················· /

  By setting these heat radiating grooves M ···, the heat dissipation of each resin component is enhanced, the thermal deformation due to the residual heat of each component after resin molding is prevented, and each resin component can be molded more accurately. It can be done. As shown in FIG. 3, the gear reducer 4 </ b> B described above accommodates the above-described gear parts and shaft parts inside a housing case configured by assembling the main body case 10 and the lid case 20. It is configured to be assembled.

  As shown in FIG. 5, the main body case 10 is set with the electric motor 4A attached to a pedestal portion 13 formed on the head thereof. In addition, since the electric motor 4A in a present Example is a well-known structure disclosed by literatures, such as Unexamined-Japanese-Patent No. 2008-86110, detailed description about this is abbreviate | omitted. Here, returning to FIG. 2, the main body case 10 has the concave first housing recess 11 in which the first gear 40 is set, the concave second housing recess 12 in which the second gear 60 is set, and the above-described case. The electric motor 4 </ b> A is formed in a shape having a pedestal portion 13 on which the electric motor 4 </ b> A is set and screw tightening openings 14.

  The first accommodating recess 11 is a cylindrical container-shaped recess having an outer diameter slightly larger than the outer diameter of the worm wheel 41 so that a worm wheel 41 of the first gear 40 described later can be received inside the recess. It is formed into a shape. A first bearing hole 11A is formed at the center of the first housing recess 11 to receive one end of a round bar-shaped support shaft 50, which will be described later, and to support the end rotatably. An opening window 11 </ b> B is formed on the side surface of the first housing recess 11 to expose the insertion port 13 </ b> A formed so as to penetrate straight from the center of the pedestal 13 to the first housing recess 11. .

  In addition, the second receiving recess 12 is formed at a stepped level with respect to the first receiving recess 11 described above, and the second gear 60 so that the second gear 60 described later can be received inside the recess. It is formed in a cylindrical container-shaped concave shape having an outer shape that is slightly larger than the outer diameter. As shown in FIG. 4, a second bearing hole 12 </ b> A that receives the shaft portion 61 of the second gear 60 and supports the coaxial portion 61 so as to be rotatable is formed at the center of the second housing recess 12. Has been. Returning to FIG. 2, a second bearing protrusion 12 </ b> B protruding in an arc shape is formed on the inner surface of the second housing recess 12 that faces the side surface of the second gear 60.

  As shown in FIG. 4, the second bearing protrusion 12B is inserted into an annular recess 63 formed in a side surface of the second gear 60 facing the second bearing projection 12B, so that the second gear 60 can be axially rotated. It is a functional part to support. Next, returning to FIG. 2, the lid case 20 will be described. The lid case 20 includes a first bearing protrusion 21A formed to project in an arc shape on the inner surface facing the first housing recess 11 of the main body case 10, and a central portion surrounded by the first bearing protrusion 21A. Are aligned with the first bearing hole 21B formed on the inner surface, the second bearing hole 22A formed through the inner surface facing the second receiving recess 12 of the main body case 10, and the screw fastening holes 14 of the main body case 10. And a screw fastening port 24... That is fastened and fixed integrally to the main body case 10.

  The first bearing protrusion 21A described above receives the spur gear 42 of the first gear 40 set in the first housing recess 11 of the main body case 10 and supports the first gear 40 so as to be capable of rotating the shaft. It has become. The first bearing hole 21B is a functional part that receives the other end portion of the above-described round bar-shaped support shaft 50 and supports the end portion so that the shaft can rotate. Further, the second bearing hole 22A is a functional part that receives the shaft portion 62 of the second gear 60 set in the second housing recess 12 of the main body case 10 and supports the second gear 60 so as to be capable of rotating the shaft. ing.

  Next, returning to FIG. 2, the configuration of each gear part and shaft part set between the main body case 10 and the lid case 20 will be described. First, the configuration of the worm 30 will be described. That is, the worm 30 has a well-known configuration in which screw-like teeth 31 are cut in a metal round bar member. The worm 30 is inserted into the insertion port 13A formed so as to penetrate straight from the center portion of the pedestal portion 13 of the main body case 10, whereby the above-described screw-like teeth 31 are opened in the opening window of the main body case 10. It is set in the main body case 10 in a state exposed to 11B.

  A flexible wire 32 that is directly connected to the output shaft of the electric motor 4A and receives power transmission is inserted into the upper end portion of the shaft of the worm 30 so as to be integrated in the rotational direction. The flexible wire 32 is formed by winding a thin steel material into a rectangular tube shape, and both ends connected to the worm 30 and the electric motor 4A are tightly wound, and the central portion in the axial direction therebetween is the neck. It is softly wound so as to be bent like a swing.

  Even if the output shaft of the electric motor 4A is assembled with a certain amount of displacement from the central axis of the worm 30, the flexible wire 32 absorbs this eccentric amount by swinging the central portion thereof. The rotation output from the electric motor 4A can be satisfactorily transmitted to the worm 30. Next, the configuration of the first gear 40 will be described. That is, in the first gear 40, a worm wheel 41 that meshes with the worm 30 and receives power transmission and a spur gear 42 having an outer diameter smaller than that of the worm wheel 41 are integrally rotated around the same axis. Thus, the configuration is formed side by side in the axial direction.

  In the first gear 40, the above-described round bar-shaped support shaft 50 is inserted into a shaft hole 43 formed through the center of the first gear 40, and the support shaft 50 allows the main gear case 10 and the lid case 20 to be pivoted. It is assembled in a state of being rotatably supported. Specifically, in the first gear 40, the worm wheel 41 portion is set in the first housing recess 11 of the main body case 10 by the above-described assembly, and the teeth 41A enter the opening window 11B and the teeth 31 of the worm 30. It is assembled in a meshed state.

  The first gear 40 is set in a state where the spur gear 42 enters the space surrounded by the first bearing protrusion 21A of the lid case 20 by the above-described assembly, and the outer peripheral surface of the teeth 42A is the first bearing. The protrusion 21A is assembled in such a state that it is supported and supported by the inner peripheral surface of the protrusion 21A from the outer peripheral side so that the shaft can rotate.

  Next, the configuration of the second gear 60 will be described. The second gear 60 is formed as a spur gear that meshes with the spur gear 42 of the first gear 40 and receives power transmission. As shown in FIG. 4, the second gear 60 has a shaft portion 61 that is inserted into the second bearing hole 12 </ b> A of the main body case 10 and is supported at the center thereof, and a second bearing hole of the lid case 20. A shaft portion 62 that is inserted into the bearing 22A and supported by the shaft is formed so as to protrude in a cylindrical shape on one side and the other side in the axial direction.

  The above-described second gear 60 is set by inserting the above-described one-side shaft portion 61 into the second bearing hole 12A of the main body case 10 and setting the other-side shaft portion 62 and the lid case 20 to the main body case 10. The cover case 20 is set so as to be covered and inserted into the second bearing hole 22A of the lid case 20 so as to be assembled in a state of being supported by the main body case 10 and the lid case 20 so as to be rotatable. Specifically, the second gear 60 is set in the second housing recess 12 of the main body case 10 by the above-described assembly, and the teeth 64 mesh with the teeth 42A of the spur gear 42 of the first gear 40. And assembled.

  In addition, the second gear 60 is a second bearing projection that protrudes in an arc shape formed in the main body case 10 in the annular concave portion 63 formed in the side surface facing the main body case 10 by the above-described assembly. 12B enters, and the second bearing projection 12B is also supported by being supported so as to be rotatable. Here, a shaft hole 65 through which the rod 3 </ b> A (see FIG. 1) serving as the output shaft is inserted is formed in the center of the second gear 60 so as to penetrate in the axial direction.

  Serration-like grooves are cut in the inner peripheral surface of the shaft hole 65 and the outer peripheral surface of the rod 3A so as to be fitted with each other. By inserting the rod 3A into the shaft hole 65, the rod 3A Are connected to the second gear 60 in an integrated state in the rotational direction. Therefore, by the above assembly, the worm 30, the first gear 40, the second gear 60, and the rod 3A are assembled in a state where they are engaged with each other so as to be able to transmit power.

  As a result, the gear reducer 4B uses the rotational power output from the electric motor 4A as the difference in the number of teeth between the worm 30 and the worm wheel 41 or the difference in the number of teeth between the spur gear 42 and the second gear 60. Thus, the speed is reduced to a reduction ratio corresponding to the difference in the number of teeth, and output to the rod 3A. Incidentally, as shown in FIG. 5, the spur gear 42 and the second gear 60 of the first gear 40 formed by resin molding are respectively provided with thin metal plates K <b> 1 and 1 having flexibility therein. K2 is integrally formed by insert molding.

  The metal plate K1 inserted in the spur gear 42 of the first gear 40 described above is formed in a long plate shape, and is arranged in a continuous manner along the entire outer periphery of the spur gear 42. Yes. Specifically, the metal plate K1 is disposed such that the plate surface faces the tooth surface of the spur gear 42, and passes through the inside of each tooth 42A and the inside of the tooth bottom portion 42B between each tooth 42A. The gear 42 is bent and formed so as to be connected in a continuous manner over the entire circumference. More specifically, the metal plate K1 is formed by being bent in the shape along the tooth profile of each tooth 42A inside each tooth 42A, and the plate surface is arranged facing the tooth surface of each tooth 42A. Has been.

  Thus, the spur gear 42 having the above-described configuration is supported from the inside so that the teeth 42A are not easily bent and deformed by the metal plate K1 inserted therein. On the other hand, the metal plate K2 inserted into the second gear 60 is also formed in a long plate shape like the above-described metal plate K1, and is connected to the entire circumference along the outer peripheral portion of the second gear 60. It is arranged in a shape. Specifically, the metal plate K <b> 2 is disposed with its plate surface facing the tooth surface of the second gear 60, and passes through the inside of each tooth 64 and the inside of the tooth bottom portion 64 </ b> B between each tooth 64. The second gear 60 is formed by being bent so as to be arranged in a continuous manner over the entire circumference.

  More specifically, the metal plate K <b> 2 is formed in each tooth 64 by being bent in a shape along the tooth profile of each tooth 64, and the plate surface is disposed facing the tooth surface of each tooth 64. Has been. Accordingly, the second gear 60 having the above-described configuration is configured to be supported from the inner side by the metal plate K2 inserted therein so that each tooth 64 is not easily bent and deformed. Accordingly, the spur gear 42 and the second gear 60 of the first gear 40 having the above-described configuration are provided with a stopper structure that locks the tilting rotation of the seat back described above with reference to FIG. In the state where the transmission rotation of each other is locked by the stopper structure 2B), between the meshing teeth (between the teeth 42A and the teeth 64) pressed against each other by the load applied from the input side or the output side thereof Even if a creep force in the rotational direction that is accompanied by forced deformation is applied to the metal plate, it is supported by the metal plates K1 and K2 inserted therein, and the creep deformation is suppressed and held.

  Thus, according to the gear reducer 4B of the present embodiment, the spur gear 42 of the resin first gear 40 and the second gear 60 made of resin are included in the gear train of the gear reducer 4B. Since the flexible metal plates K1 and K2 are insert-molded inside the teeth 42A and 64, the teeth 42A and 64 are supported by the metal plates K1 and K2 so that they are not easily deformed by creep. Is done. Thus, the creep of the teeth 42A and 64 of the first gear 40 and the second gear 60 made of resin is achieved without increasing the size of the first gear 40 and the second gear 60 (the configuration of the gear reducer 4B). Deformation can be suppressed.

  Also, the metal plates K1 and K2 are insert-molded in a bent form so as to be arranged in a shape along each tooth shape inside each tooth 42A of the first gear 40 and each tooth 64 of the second gear 60. Thus, the metal plates K1 and K2 can be supported so that the creep deformation of the teeth 42A and 64 can be more effectively suppressed. Further, the metal plates K1 and K2 pass over the entire circumference of the first gear 40 and the second gear 60 through the inside of the teeth 42A and 64 and the inside of the tooth bottom portions 42B and 64B between the teeth 42A and 64. By being formed as a single metal plate arranged in a single piece, the creep deformation of each tooth 42A, 64 is continuously arranged across the inside of each tooth 42A, 64 and its vicinity. It can suppress more effectively by the metal plates K1 and K2 which are made.

  Further, each of the metal plates K1 and K2 is formed as a plate-like member having a very thin plate thickness compared to the tooth thickness of each tooth 42A of the first gear 40 and each tooth 64 of the second gear 60. Therefore, it is possible to increase the rigidity of the teeth 42A and 64 without greatly increasing the weight of the first gear 40 and the second gear 60.

  As mentioned above, although the embodiment of the present invention has been described using one example, the present invention can be implemented in various forms in addition to the above example. For example, the gear reducer according to the present invention operates a drive device for raising and lowering a vehicle seat to change the installation height relative to the floor, a drive device for folding the seat back, and an active headrest. It can be applied as a speed reducer for decelerating the rotational output of various drive devices provided in association with a vehicle seat.

  Moreover, the gear reducer of this invention can be used for the various uses for decelerating and outputting rotational power by the rotational power transmission of a gear train besides the use relevant to the above-mentioned vehicle seat. Moreover, in the said Example, although what carried out insert molding of the metal plates K1 and K2 was illustrated in both the spur gear 42 and the 2nd gear 60 of the resin-molded 1st gear 40, a metal plate is only in one of them. It may be insert-molded. Further, a metal plate may be formed by insert molding on the worm wheel 41 of the resin first gear 40 that meshes with the metal worm 30. Moreover, the gear which insert-molds a metal plate is not limited to a spur gear, Other gears, such as a helical gear, may be sufficient.

DESCRIPTION OF SYMBOLS 1 Back frame 1A Support bracket 1B Reinforcement pipe 2 Cushion frame 2A Forward tilt locking surface 2B Rear tilt locking surface 3 Reclining device 3A Rod 4 Drive device 4A Electric motor 4B Gear reducer 10 Main body case 11 1st accommodation recessed part 11A 1st Bearing hole 11B Opening window 12 Second receiving recess 12A Second bearing hole 12B Second bearing projection 13 Base portion 13A Insertion port 14 Screw fastening port 20 Lid case 21A First bearing projection 21B First bearing hole 22A Second bearing hole 24 Screw fastening port 30 Worm 31 Tooth 32 Flexible wire 40 First gear 41 Worm wheel 41A Tooth 42 Spur gear 42A Tooth 42B Tooth bottom 43 Shaft hole 50 Support shaft 60 Second gear 61 Shaft 62 Shaft 63 Recess 64 Tooth 64B Tooth bottom 65 Shaft hole M Radiation groove K1 Metal plate K2 metal plate

Claims (3)

A gear reducer that decelerates and outputs rotational power by transmission of rotational power of a gear train,
At least one gear constituting the gear train is made of a resin, and a flexible metal plate is formed by insert molding inside each tooth, and the metal plate is formed integrally therewith. The gear speed reduction is characterized in that the surface is arranged so as to face the tooth surface of each tooth, and is configured to support each tooth that becomes a meshing portion by the metal plate so as to be hard to be creep-deformed. Machine. The gear reducer according to claim 1,
A gear reducer, wherein the metal plate is insert-molded in a bent form so as to be arranged along the tooth profile of each tooth inside the tooth. The gear reducer according to claim 1 or 2,
The metal plate is formed as a single metal plate that is arranged in a continuous manner over the entire circumference of the gear through the inside of each tooth and the inside of the root portion between each tooth. Gear reducer characterized by

Images