JP4586384B2 - Gear manufacturing method and gear manufacturing jig - Google Patents

Description

The present invention relates to the production side Ho及 beauty gear manufacturing jig gear which is disposed an elastic ring member on the inner circumferential side of the teeth.

  The electric power steering apparatus for a vehicle includes an electric motor for assisting steering and a reduction gear mechanism that transmits a rotational force of the electric motor to the steering means, and the operation of the steering means according to the rotation of the steering wheel is described above. It is configured to assist by the rotation of the electric motor and reduce the labor burden on the driver for steering.

  The reduction gear mechanism includes a small gear coupled to the output shaft of the electric motor and a large gear meshing with the small gear, and the large gear is a rotation shaft of the steering means. It is fixed on the way. The column shaft is rotatably supported in the housing via rolling bearings disposed on both axial sides of the large gear.

  In the electric power steering apparatus using the electric motor, when the electric motor is driven, the small gear rotates, and vibration noise due to gear backlash and meshing is generated between the small gear and the large gear. To do. The vibration is transmitted to the steering wheel attached to the steering means and transmitted to the driver. For this reason, there is a problem that noise is generated in the vehicle and the driver feels uncomfortable.

Therefore, the large gear externally fitted to the column shaft includes a tooth portion meshing with the small gear, an elastic ring disposed on the inner peripheral side of the tooth portion, and an inner peripheral side of the elastic ring. A structure in which the elastic ring body absorbs vibrations and noises caused by gear backlash and meshing has been devised (see, for example, Patent Document 1).
Japanese Utility Model Publication No. 64-32270

  However, the large gear of Patent Document 1 has a configuration in which an elastic ring is disposed between a metal ring externally fitted to the column shaft and a tooth portion. Thus, when gear cutting is performed on the outer peripheral surface of the gear cutting front tooth portion, the elastic ring body is distorted by the force acting on the gear cutting front tooth portion, and the gear cutting front tooth portion is against the column shaft or the metal ring body. The column shaft is bent in the axial direction and the axial radial direction. For this reason, it has been difficult to improve the concentric accuracy of the tooth portion with respect to the column shaft or the metal ring.

The present invention has been made in view of such circumstances, production side of the gear that can improve the concentric accuracy of the teeth of the gear which is disposed an elastic annulus between the teeth and the metal ring member Ho及 It is an object to provide a jig for manufacturing a gear.

  The gear manufacturing method according to the first aspect of the present invention includes an annular tooth portion, an elastic ring disposed on the inner peripheral side of the tooth portion, and a metal disposed on the inner peripheral side of the elastic ring. In a method of manufacturing a gear including an annular body, an elastic ring body is disposed on an inner circumferential side of an annular gear cutting front tooth portion, a metal ring body is disposed on an inner circumferential side of the elastic ring body, and the gear cutting is performed. At least one first fitting portion is formed on one side surface of the front tooth portion, and at least one second fitting portion is formed on the same side surface as the first side surface of the metal ring body so as to have a gear before cutting. And forming a front part of the gear to be externally fitted to the shaft body, having a surface with a size smaller than the outer diameter of the gear before gear cutting, and a hole for inserting the shaft body in the center of the surface. The shaft is inserted into a fixing jig formed with first and second fitted portions that fit into the first and second fitting portions, respectively, And second fitting The parts respectively fitted in the first and second fitting portions, and fixing the toothed anterior, characterized in that the gear cutting of tooth cutting anterior.

  The gear manufacturing method according to the second aspect of the present invention includes an annular tooth portion, an elastic ring disposed on the inner peripheral side of the tooth portion, and a metal disposed on the inner peripheral side of the elastic ring. In a method of manufacturing a gear including an annular body, an elastic ring body is disposed on an inner circumferential side of an annular gear cutting front tooth portion, a metal ring body is disposed on an inner circumferential side of the elastic ring body, and the gear cutting is performed. At least one first fitting portion is formed on one side surface of the front tooth portion to form a gear before cutting gear, and the gear before cutting gear is externally fitted to a shaft body, At least one second fitting portion is formed on an outer peripheral surface of the shaft body before the gear cutting gear, and has one surface having a size smaller than the outer shape of the gear before gear cutting, and the shaft body is provided at a central portion of the one surface. A first fitting portion that is fitted to the first fitting portion is formed on the one surface, and the second fitting portion is fitted inside the hole portion. Second fit to do The shaft body is inserted into a fixing jig in which a portion is formed, the first and second fitted parts are fitted into the first and second fitting parts, and the tooth cutting front tooth part Is fixed, and the tooth cutting front tooth part is processed.

A gear manufacturing jig according to a third aspect of the present invention includes an annular gear front tooth portion, an elastic ring disposed on the inner peripheral side of the gear cutting front tooth portion, and an inner peripheral side of the elastic ring member. A gear manufacturing jig for fixing a gear front tooth portion by inserting a shaft body externally fitted with a gear wheel pre-cut gear provided with a disposed metal ring, from the outer shape of the gear front gear It has one surface with a small size, and has a hole portion into which the shaft body is inserted into the center portion of the one surface, and the one surface is formed on at least one side surface of the tooth cutting front tooth portion. A first fitted portion that fits with the fitting portion, and a second fitted portion that fits into at least one second fitting portion formed on the same side surface as the first side surface of the metal ring. Part.

A gear manufacturing jig according to a fourth aspect of the present invention includes an annular gear cutting front tooth portion, an elastic ring disposed on the inner peripheral side of the gear cutting front tooth portion, and an inner peripheral side of the elastic ring member. A gear manufacturing jig for fixing a gear front tooth portion by inserting a shaft body externally fitted with a gear wheel pre-cut gear provided with a disposed metal ring, from the outer shape of the gear front gear It has one surface with a small size, and has a hole portion into which the shaft body is inserted into the center portion of the one surface, and the one surface is formed on at least one side surface of the tooth cutting front tooth portion. A first fitted portion that fits with the mating portion, and the inside of the hole portion is at least one first formed on the outer peripheral surface on the gear-cutting gear side of the shaft body on the same side as the one side surface. It has the 2nd to-be-fitted part fitted to 2 fitting parts, It is characterized by the above-mentioned.

In the first invention and the third invention, a fixing jig that is fitted to the shaft body and fixed to the gear includes a metal ring body that is externally fitted to the shaft body, and the gear cutting front tooth portion. Even if an elastic ring is disposed between the metal ring and the tooth cutting front tooth portion, the metal ring and the gear cutting front tooth portion are fixed by the fixing jig. Is done. For this reason, when a tooth part is formed by cutting the front tooth part of the gear cutting, the metal toothed body is cut through the elastic ring body by the force acting on the tooth cutting front tooth part. In contrast, it is possible to prevent the shaft body from being bent in the axial direction and the radial direction.

In the second invention and the fourth invention, since the fixing jig that is fitted into the shaft body and fixed to the gear fits into the shaft body and the tooth cutting front tooth portion, Even if an elastic ring body is disposed between the metal ring body and the gear cutting front tooth portion, the shaft body and the gear cutting front tooth portion are fixed by the fixing jig. For this reason, when the tooth part is formed by performing gear cutting processing on the tooth cutting front tooth part, the tooth cutting front tooth part is moved to the shaft body via the elastic ring body by a force acting on the tooth cutting front tooth part. On the other hand, bending in the axial direction and the radial direction of the shaft body can be prevented.

  In the present invention, the concentric accuracy of the tooth portion of the gear in which the elastic ring body is disposed between the tooth portion and the metal ring body can be improved.

Hereinafter, the present invention will be described with reference to the drawings showing embodiments thereof.
Embodiment 1
FIG. 1 is a cross-sectional view showing the overall configuration of an electric power steering apparatus using a large gear 4 according to the present invention.

  The electric power steering apparatus includes an electric motor 1 for assisting steering, a small gear 3 connected to an output shaft 11 of the electric motor 1 and a reduction gear mechanism 2 having a large gear 4 meshing with the small gear 3, and a reduction gear mechanism. 2 and a steering means 6 connected to the reduction gear mechanism 2.

  The steering means 6 includes an upper column shaft 61 connected to the steering wheel 12 for steering at the upper end, a torsion bar 63 connected to the upper column shaft 61, and a lower column shaft connected to the torsion bar 63. 64. The lower column shaft 64 is connected to a rack and pinion type steering mechanism via a universal joint (not shown).

  On the outer periphery of the torsion bar 63, a torque sensor 7 for detecting torque acting on the upper column shaft 61 by the rotation of the steering wheel 12 is disposed. Further, the large gear 4 is externally fitted to the lower column shaft 64.

  In the electric power steering apparatus, when the steering wheel 12 is rotated, torque is applied to the upper column shaft 61 by the operation, and the torque sensor 7 detects the torque. The electric motor 1 is driven and controlled based on the detected torque, the small gear 3 is rotated, and the lower column shaft 64 is rotated by the rotation of the large gear 4 to assist the steering force.

  FIG. 2 is a front view of the large gear 4 according to the present invention. In the figure, reference numeral 48 denotes a tooth portion, the outer periphery of the metal portion 48b is a synthetic resin portion 48a, and an elastic ring body 42 made of rubber or synthetic resin is disposed on the inner peripheral side of the tooth portion 48. . A metal ring 43 is disposed on the inner peripheral side of the elastic ring 42. The large gear 4 is externally fitted to the lower column shaft 64.

  On the surface of the metal ring body 43, holes 45, 45... Having appropriate diameters are provided at equal intervals in a position concentric with the center of the lower column shaft 64. Similarly, holes 45, 45,... Having appropriate diameters are provided on the surface of the metal part 48b of the tooth part 48 in an equally spaced manner.

  FIG. 3 is a perspective view showing configurations of the large gear 4 and the fixing jig 8 according to the present invention. In the figure, reference numeral 41 denotes a tooth cutting front tooth portion, and a synthetic resin portion 41a is formed on the outer periphery of a metal portion 41b. 8 has a hole (not shown) for inserting the lower column shaft 64 in the central portion, and the tooth cutting front tooth portion 41 and the metal ring are formed on the side surface having a size smaller than the outer diameter of the gear cutting front tooth portion 41. This is a fixing jig provided with pins 81, 81... That fit into holes 45, 45.

  Next, a method for gear cutting on the front tooth portion 41 will be described. An elastic ring body 42 is disposed on the inner circumferential side of the gear cutting front tooth portion 41, and a metal ring body 43 is disposed on the inner circumferential side of the elastic ring body 42 to form the large gear 4. Holes 45, 45... Having appropriate diameters are formed on the surface of the metal portion 41b of the front tooth portion 41. On the surface of the metal ring body 43, holes 45, 45... Having appropriate diameters are formed at equal intervals at the concentric position with the center of the lower column shaft 64. The large gear 4 is externally fitted to the lower column shaft 64, the lower column shaft 64 is fitted to the fixing jig 8, and the holes 45, 45... Are fitted to the pins 81, 81. 8 is fixed to the large gear 4. Thereby, even if the elastic ring body 42 is disposed between the gear cutting front tooth portion 41 and the metal ring body 43, the gear cutting front tooth portion 41 and the metal ring body 43 are connected via the fixing jig 8. Therefore, when a force acting in the axial direction and the axial radial direction is generated on the gear cutting front tooth portion 41 during gear cutting, the gear cutting front tooth portion 41 bends with respect to the metal ring 43. Without this, the concentric accuracy of the tooth portion 48 can be improved.

  Further, by applying the method of Embodiment 1 to the gear before the synthetic resin portion 48a is formed on the outer periphery of the metal portion 48b, not only the bending at the time of gear cutting but also the molding of the synthetic resin portion 48a. Even when a force acting in the axial direction and the axial radial direction is generated on the metal part 48b, the metal part 48b is not bent with respect to the metal ring body 43, and the concentric accuracy of the tooth part 48 is increased. Is possible.

  In the present embodiment, the four holes 45, 45... Are provided on the surfaces of the tooth cutting front tooth portion 41, the tooth portion 48, and the metal ring body 43 at equal intervals, but the number of the holes 45 is limited to four. However, it is sufficient that at least one of the front tooth part 41, the tooth part 48, and the metal ring body 43 is provided. Further, it is not always necessary to provide them at equal intervals, and the fixing jig 8 fixed to the gear cutting front tooth portion 41 and the metal ring body 43 can fix the gear cutting front tooth portion 41 to the metal ring body 43. Any arrangement may be used.

  In the present embodiment, the holes 45, 45... Are provided, but are not limited to holes and may be grooves. Moreover, the recessed part which has arbitrary cross-sectional shapes may be sufficient. Further, instead of the holes 45, 45..., A pin-shaped one or a protrusion having an arbitrary cross-sectional shape may be used. In this case, the pin 81 of the fixing jig 8 needs to be changed as necessary so that the fixing jig 8 can be fixed to the large gear 4.

  The holes 45, 45... May be provided not only on one side surface of the large gear 4 but also on both side surfaces. The fixing jig 8 is not limited to a substantially cylindrical shape as long as it can be inserted into the lower column shaft 64, and may be any one that can restrain the rotation around the axis of the lower column shaft 64. You may have arbitrary external shapes.

  In the embodiment described above, the large gear 4 is provided with the holes 45, 45..., But is not limited thereto, and may be provided in the small gear 3. It can also be provided on other gears used in vehicles.

Embodiment 2
FIG. 4 is a perspective view showing configurations of the large gear 4 and the fixing jig 8 according to the second embodiment. In the figure, 45 is a hole provided in the surface of the metal part 41b of the tooth cutting front tooth part 41 as in the first embodiment. Serrations 46 are formed in the vicinity of the large gear 4 and on the outer periphery of the lower column shaft 64. The fixing jig 8 has a hole (not shown) for insertion into the lower column shaft 64 at the center, and is fitted into holes 45, 45... Provided in the gear cutting front tooth 41 on the side surface. Pins 81 are provided. A serration 82 is formed on the inner side of the hole so as to fit into the serration 46 formed on the outer periphery of the lower column shaft 64.

  Next, a method for gear cutting on the front tooth portion 41 will be described. Since the formation of the large gear 4 is the same as that of the first embodiment, the description thereof is omitted. The large gear 4 is externally fitted to the lower column shaft 64, the lower column shaft 64 is inserted into the fixing jig 8, the holes 45, 45... Are fitted to the pins 81, 81, and the serration 46 is the serration 82. The fixing jig 8 is fixed to the large gear 4 so as to be fitted to the large gear 4. Thus, as in the case of the first embodiment, the gear cutting front tooth portion 41 and the lower column shaft 64 are fixed via the fixing jig 8, so that the gear cutting front tooth portion 41 is used during gear cutting. When a force acting in the axial direction and the axial radial direction is generated, the tooth cutting front tooth portion 41 does not bend with respect to the lower column shaft 64, and the concentric accuracy of the tooth portion 48 can be improved. .

  In the second embodiment, the serration 46 is formed on the outer periphery of the lower column shaft 64. However, the serration shape is not limited, and a spline shape or the like may be used. Further, it may be configured such that at least one convex protrusion or concave groove having an appropriate length is provided along the axial length direction of the lower column shaft 64.

Embodiment 3
FIG. 5 is a perspective view showing configurations of the large gear 4 and the fixing jig 8 according to the third embodiment. In the figure, 45 is a hole provided in the surface of the metal part 41b of the tooth cutting front tooth part 41 as in the first embodiment. Flat portions 47 are provided on the outer periphery of the lower column shaft 64 in the axial direction. The fixing jig 8 has a hole (not shown) for insertion into the lower column shaft 64 at the center, and is fitted into holes 45, 45... Provided in the gear cutting front tooth 41 on the side surface. Pins 81 are provided. On the inner side of the hole portion, flat portions 83 and 83 are formed that fit into flat portions 47 and 47 formed on the outer periphery of the lower column shaft 64.

  Next, a method for gear cutting on the front tooth portion 41 will be described. Since the formation of the large gear 4 is the same as that of the first embodiment, the description thereof is omitted. The large gear 4 is externally fitted to the lower column shaft 64, the lower column shaft 64 is inserted into the fixing jig 8, and the holes 45, 45... Are fitted to the pins 81, 81. The fixing jig 8 is fixed to the large gear 4 so that the flat surface portion 47 of the fixing jig 8 is fitted to the flat surface portion 83 of the fixing jig 8. Thus, as in the case of the first embodiment, the gear cutting front tooth portion 41 and the lower column shaft 64 are fixed via the fixing jig 8, so that the gear cutting front tooth portion 41 is used during gear cutting. When a force acting in the axial direction and the axial radial direction is generated, the tooth cutting front tooth portion 41 does not bend with respect to the lower column shaft 64, and the concentric accuracy of the tooth portion 48 can be improved. .

  In the third embodiment, two flat portions 47 are formed on the outer periphery of the lower column shaft 64 so as to be opposed to each other in the radial direction. However, the number is not limited to two, and one or three or more are provided. There may be. Needless to say, the number of flat portions 83 formed inside the hole of the fixing jig 8 is changed in correspondence with the number of flat portions 47.

It is sectional drawing which shows the whole structure of the electric power steering apparatus using the large gear concerning this invention. It is a front view of the large gear concerning the present invention. It is a perspective view which shows the structure of the large gearwheel and fixing jig which concern on this invention. It is a perspective view which shows the structure of the large gear of Embodiment 2, and a fixing jig. It is a perspective view which shows the structure of the large gear of Embodiment 3, and a fixing jig.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electric motor 2 Reduction gear mechanism 3 Small gear 4 Large gear (gear)
6 Steering means 7 Torque sensor 8 Fixing jig (jig manufacturing jig)
41 tooth cutting front tooth portion 41a synthetic resin portion 41b metal portion 42 elastic ring body 43 metal ring body 45 hole (first and second fitting portions, concave portion)
46 Serration (second fitting part)
47 Plane part (second fitting part)
48 Teeth 48a Synthetic resin 48b Metal 61 Upper column shaft 64 Lower column shaft (shaft)
81 pins (first and second mated parts)
82 Serration (second mating part)
83 Plane part (second mating part)

Claims (4)

In a method of manufacturing a gear comprising an annular tooth portion, an elastic ring disposed on the inner peripheral side of the tooth portion, and a metal ring disposed on the inner peripheral side of the elastic ring,
An elastic ring body is arranged on the inner peripheral side of the annular tooth cutting front tooth part,
Arranging a metal ring on the inner peripheral side of the elastic ring,
Forming at least one first fitting portion on one side surface of the tooth cutting front tooth portion;
Forming at least one second fitting portion on the same side surface as the first side surface of the metal ring body to form a gear before cutting;
The outer gear is externally fitted to the shaft body,
The gear has a surface smaller than the outer diameter of the gear before cutting, and has a hole into which the shaft body is inserted in the center of the surface. The surface is the first and second fitting portions, respectively. The shaft body is inserted into a fixing jig in which first and second fitted portions to be fitted are formed,
Fitting the first and second fitted parts to the first and second fitting parts, respectively;
A gear manufacturing method, wherein the tooth cutting front tooth part is fixed and the gear cutting front tooth part is cut. In a method of manufacturing a gear comprising an annular tooth portion, an elastic ring disposed on the inner peripheral side of the tooth portion, and a metal ring disposed on the inner peripheral side of the elastic ring,
An elastic ring body is arranged on the inner peripheral side of the annular tooth cutting front tooth part,
Arranging a metal ring on the inner peripheral side of the elastic ring,
Forming at least one first fitting portion on one side surface of the gear cutting front tooth portion to form a gear front gear;
The outer gear is externally fitted to the shaft body,
Forming at least one second fitting portion on the outer peripheral surface on the gear-cutting gear side of the shaft on the same side as the one side surface;
It has one surface smaller than the outer shape of the gear before gear cutting, and has a hole portion into which the shaft body is inserted at the center portion of the one surface, and the one surface is fitted to the first fitting portion. 1 fitted portion is formed, and the shaft body is inserted into a fixing jig in which a second fitted portion to be fitted to the second fitting portion is formed inside the hole portion,
Fitting the first and second fitted parts to the first and second fitting parts, respectively;
A gear manufacturing method, wherein the tooth cutting front tooth part is fixed and the gear cutting front tooth part is cut. A gear-cutting front gear comprising an annular gear-cut front tooth portion, an elastic ring disposed on the inner peripheral side of the gear-cut front tooth portion, and a metal ring disposed on the inner peripheral side of the elastic ring body. A gear manufacturing jig that inserts an externally fitted shaft body and fixes the tooth cutting front tooth portion,
It has one surface with a size smaller than the outer shape of the gear before cutting, and has a hole into which the shaft body is inserted at the center of the surface, and the one surface is formed on one side surface of the gear cutting front tooth portion. A first fitted portion that fits with at least one first fitting portion;
A gear manufacturing jig comprising: a second fitted portion that fits into at least one second fitting portion that is formed on the same side surface as the first side surface of the metal ring body. A gear-cutting front gear comprising an annular gear-cut front tooth portion, an elastic ring disposed on the inner peripheral side of the gear-cut front tooth portion, and a metal ring disposed on the inner peripheral side of the elastic ring body. A gear manufacturing jig that inserts an externally fitted shaft body and fixes the tooth cutting front tooth portion,
It has one surface with a size smaller than the outer shape of the gear before cutting, and has a hole into which the shaft body is inserted at the center of the surface, and the one surface is formed on one side surface of the gear cutting front tooth portion. A first fitted portion that fits with at least one first fitting portion, and the inner side of the hole portion is the outer peripheral surface on the gear cutting front gear side of the shaft body on the same side as the side surface of the first side. A gear manufacturing jig, comprising: a second fitted portion that fits into at least one second fitting portion formed on the gear.

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