JP4429944B2 - Method of manufacturing a rolling die for hourglass worms and an apparatus for manufacturing a rolling die for hourglass worms - Google Patents

Description

  The present invention relates to a method for manufacturing a rolling dies for hourglass worms used when manufacturing hourglass worms by rolling, and an apparatus for manufacturing the rolling dies.

  Conventionally, a speed reduction mechanism using an hourglass worm is known. Since the hourglass worm has a larger number of meshing teeth with the worm wheel that meshes with the cylindrical worm, it is used, for example, in a small motor with a speed reduction mechanism used in a vehicle or a high load speed reducer.

  In general, this hourglass worm is produced by cutting with a thread cutting machine, hobbing machine, etc., or grinding with a grindstone, but these machining methods require a long machining time and mass production of hourglass worms. It was difficult to do. Therefore, in order to mass-produce the hourglass worm, a rolling process using a die is performed. The manufacturing method of the die | dye used for this rolling is disclosed by patent document 1. FIG.

  Patent Document 1 discloses a method for manufacturing a round die. A round die is manufactured by forming a tooth groove for rolling a hourglass worm on the outer peripheral surface of a disk-shaped workpiece using a rotary tool (rotary grindstone). In the cross section along the radial direction of the workpiece, the outer peripheral surface of the workpiece bulges radially outward in an arc shape having a curvature equal to the curvature radius of the root surface of the hourglass worm.

  The rotary tool is fixed to a swing unit supported by two swing arms. Specifically, the holder is provided with two holders projecting toward the workpiece, and the rotary tool is rotatably supported by the holder. A drive motor for rotating the rotary tool is mounted on one of the holders. In addition, an auxiliary motor for tilting the rotary tool is mounted on the surface of the swing unit opposite to the workpiece so that the axis of the rotary tool is tilted relative to the axis of the workpiece by the lead angle of the hourglass worm. Yes.

When forming the tooth groove for rolling the hourglass worm on the outer peripheral surface of the workpiece, the rotary tool and the workpiece with the axis of the rotary tool inclined with respect to the axis of the workpiece by the lead angle of the hourglass worm. Will be rotated. At the same time, the swing arm swings the swing unit around the center of curvature of the arc formed on the outer peripheral surface of the work in synchronization with the rotation of the work. As a result, the rotary tool is swung around the center of curvature as the swing center. Further, the rotary tool is fed to the workpiece side by extending or contracting the swing arm or the holder. In this way, while keeping the tilt of the rotary tool constant, the rotary tool is reciprocally swung within the thickness range of the workpiece, and at the same time, the workpiece is driven to rotate forward and backward, thereby forming a drum-shaped worm on the outer peripheral surface of the workpiece. A tooth gap for rolling is formed.
JP 2003-320434 A

  However, in the method of manufacturing a round die disclosed in Patent Document 1, the rotary tool is rotated and swung by a swing unit, and further on the workpiece side in order to form a tooth groove in the die. It is sent. Therefore, an error due to rotation, an error due to rocking, and an error due to feeding are accumulated, and there is a possibility that errors such as the pitch of tooth grooves formed on the outer peripheral surface may increase. Since the hourglass worm provided in the small motor requires high accuracy, it is desirable that the hourglass worm be manufactured with a high-precision round die.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a method for manufacturing a drum worm rolling die and an apparatus for manufacturing a drum worm rolling die capable of improving accuracy. It is to provide.

In order to solve the above-mentioned problem, the invention described in claim 1 is for processing a disk-shaped workpiece to bulge into an arc shape equal to the curvature of the root surface of the hourglass worm to form the hourglass worm. A method of manufacturing a drum worm rolling die for forming a drum worm rolling die having an outer peripheral surface having a tooth groove, wherein the rotating grindstone for forming the tooth groove is only a lead angle of the hourglass worm. The axis of the workpiece is arranged to be inclined with respect to the axis of the workpiece, and the workpiece is swung around the center of curvature of the outer peripheral surface in synchronization with the rotation of the workpiece, and the rotating grindstone is moved to the workpiece. The axis of the turning axis for turning the workpiece is arranged at a position away from the center of curvature of the outer peripheral surface so that the workpiece is fed along the radial direction, and the relative position between the workpiece and the rotating grindstone But said While controlling the position of the workpiece according to the amount of rotation of the workpiece so as to be the same as the relative position of the workpiece and the rotating grindstone when the workpiece is turned with the center of curvature of the circumferential surface as the turning center The amount of feeding the rotating grindstone to the workpiece side is controlled .

According to a second aspect of the present invention, in the manufacturing method of the hourglass worm rolling die according to the first aspect, the axis of the pivot shaft passes through the axis of the workpiece and the center of the workpiece in the thickness direction. Place it so that it passes through the intersection with the line .

According to a third aspect of the present invention, there is provided the method for manufacturing the hourglass worm rolling die according to the first or second aspect , wherein the drum is mounted on a table provided in a general-purpose screw grinder and slidably moved by a slide mechanism. A turning table that is turned around the turning axis, a work axis that is placed on the turning table and rotates the work, and a synchronizing means that turns the turning axis in synchronization with the rotation of the work axis, The relative position between the work and the rotating grindstone is the same as the relative position between the work and the rotating grindstone when the work is swiveled with the center of curvature of the outer peripheral surface as the turning center. Using a manufacturing apparatus comprising a control means for controlling the position of the workpiece according to the amount of rotation and controlling the amount of feeding the rotating grindstone to the workpiece side, Serial with synchronizing the pivoting of the workpiece, to control the position of the workpiece is slid to the table.

According to a fourth aspect of the present invention, there is provided an outer peripheral surface having a tooth groove for processing a disk-shaped workpiece to bulge in an arc shape equal to the curvature of the bottom surface of the hourglass worm to form the hourglass worm. A manufacturing method of a drum worm rolling die for forming a drum worm rolling die provided, wherein a rotating grindstone forming the tooth gap is set to an axis of the workpiece by an advance angle of the drum worm. The axis is inclined and arranged, and the workpiece is rotated around the center of curvature of the outer peripheral surface in synchronization with the rotation of the workpiece, and the rotating grindstone is rotated along the radial direction of the workpiece. as fed to the side, a turning table is pivoted at pivot while being placed on the general-purpose screw grinding machine table, is placed on the turn table, turning of the workpiece is pivoted integrally with the turntable A slide table for causing the center and the axis of the swivel axis to coincide, a work axis disposed on the slide table for rotating the work, and synchronization for synchronizing the rotation of the work and the rotation of the swivel axis The rotation of the workpiece and the turning of the workpiece are synchronized using a manufacturing apparatus provided with means.

The invention of claim 5 is a method of manufacturing a hourglass worm for rolling die according to 請 Motomeko 4, to match the center of curvature of the outer peripheral surface with the axis of the pivot for pivoting said workpiece .

According to a sixth aspect of the present invention, in the method for manufacturing the hourglass worm rolling die according to any one of the third to fifth aspects, the turning table is connected to the work shaft and A work shaft drive motor for rotating the work shaft is provided.

A seventh aspect of the present invention is the method of manufacturing the hourglass worm rolling die according to any one of the third to fifth aspects, wherein the main shaft of the general-purpose screw grinder is connected to the work shaft. Connected at the part.
According to an eighth aspect of the present invention, an outer peripheral surface having a tooth groove for forming a hourglass worm by processing a disk-shaped workpiece and bulging into an arc shape equal to the curvature of the root surface of the hourglass worm. An apparatus for manufacturing a drum-shaped worm rolling die for forming a drum-shaped worm rolling die provided, wherein the swivel table is placed on a table of a general-purpose screw grinder and swiveled on a swivel axis, A slide table placed on a swivel table, passing through the axis of the workpiece and parallel to the swivel table, and aligning the center of curvature of the outer peripheral surface with the axis of the swivel axis; and on the slide table A workpiece axis that rotates the workpiece, and is arranged with its axis inclined with respect to the axis of the workpiece by the advance angle of the hourglass worm, and along the radial direction of the workpiece A rotary grindstone that forms a tooth groove for forming the hourglass worm on the workpiece, and the pivot is swiveled in synchronization with the rotation of the workpiece shaft, thereby bringing the workpiece into the center of curvature. And a synchronizing means for rotating in synchronization with the rotation of the workpiece.

According to the ninth aspect of the present invention, an outer peripheral surface having a tooth groove for forming a drum-shaped worm by processing a disk-shaped workpiece and bulging in an arc shape equal to the curvature of the root surface of the hourglass worm. An apparatus for manufacturing a drum worm rolling die for forming a drum worm rolling die provided, which is mounted on a table provided in a general-purpose screw grinder and slidably moved by a slide mechanism, and a pivot axis A turning table that is swiveled in, a work axis that is placed on the turning table and that rotates the work, and an axis that is inclined with respect to an axis of the work by an advance angle of the hourglass worm, A rotating grindstone that is fed to the workpiece side along the workpiece radial direction to form a tooth groove for forming the hourglass worm on the workpiece, and the pivot shaft is swung in synchronization with the rotation of the workpiece shaft. And the relative position between the workpiece and the rotating grindstone is the same as the relative position between the workpiece and the rotating grindstone when the workpiece is swung around the center of curvature of the outer peripheral surface. And a control means for controlling the position of the workpiece by sliding the table in accordance with the rotation amount of the workpiece and controlling the amount of the rotating grindstone to be fed to the workpiece side.

The invention according to claim 1 0, in the manufacturing apparatus of hourglass worm for rolling die according to claim 9, the axis of the work shaft, the axis of said pivot axis is perpendicular.
The invention of claim 1 1, in the apparatus for manufacturing a hourglass worm for rolling die according to any one of claims 8 to 1 0, wherein the turntable is connected to the workpiece axis And a work shaft drive motor for rotating the work shaft.

The invention according to claim 1 2, in the apparatus for manufacturing a hourglass worm for rolling die according to any one of claims 8 to 1 0, and the universal screw grinder spindle and the workpiece axis Is provided.

(Function)
According to the first and fourth aspects of the present invention, the turning operation necessary for forming the tooth gap for forming the hourglass worm on the outer peripheral surface of the work is performed by turning the work. Further, by feeding the rotating grindstone toward the workpiece along the radial direction of the workpiece, a tooth groove for forming the hourglass worm is formed. Therefore, compared with the case where only one of the workpiece and the rotating grindstone is turned and fed, the generation of the accumulated error is suppressed. Therefore, the accuracy of the manufactured hourglass worm die can be improved.

According to the first aspect of the present invention, even if the axis of the pivot axis is disposed at a position away from the center of curvature of the outer peripheral surface of the hourglass worm rolling die formed by machining the workpiece. The tooth groove for forming the hourglass worm is formed on the outer peripheral surface of the workpiece in the same way as when the center of curvature of the outer peripheral surface of the hourglass worm rolling die formed by machining the workpiece is turned. Is done. Further, the degree of freedom of the arrangement position of the swivel axis is increased as compared with the case where the axis of the swivel axis is made coincident with the center of curvature of the outer peripheral surface of the hourglass worm rolling die formed by machining the workpiece.

According to the second aspect of the present invention, the intersection of the rotation axis of the workpiece and the center line passing through the center in the thickness direction of the workpiece is a point that becomes the center of the workpiece. Since the axis of the turning axis passes through the point that is the center of the work, the work is turned stably.
According to the invention described in claim 3, the work is swung with the center of curvature of the outer peripheral surface of the hourglass worm rolling die formed by processing the work as a relative position between the work and the rotating grindstone as the turning center. The position control of the work performed so as to be the same as the relative position between the work and the rotating grindstone in the case is easily performed by sliding the table according to the rotation amount of the work. Further, by using a manufacturing apparatus placed on the table of a general-purpose screw grinding machine, it is not necessary to manufacture a completely new apparatus from scratch.

According to the fourth aspect of the present invention, the axis of the turning axis and the turning center of the workpiece can be easily matched by sliding the slide table. Further, by using a manufacturing apparatus placed on the table of a general-purpose screw grinding machine, it is not necessary to manufacture a completely new apparatus from scratch.

According to the fifth aspect of the present invention , the workpiece can be easily obtained by matching the axis of the pivot axis with the center of curvature of the outer peripheral surface of the hourglass worm rolling die formed by machining the workpiece. The workpiece is turned around the center of curvature of the outer peripheral surface of the workpiece .

According to the sixth aspect of the present invention, the workpiece is driven by the workpiece axis driving motor provided in the turning table. Therefore, when using a general-purpose screw grinder, even if it is difficult to connect a drive mechanism for rotating the workpiece to the workpiece, the workpiece can be rotated by the workpiece axis driving motor connected to the workpiece axis.

According to the seventh aspect of the invention, since the main shaft of the general-purpose screw grinder and the work shaft are connected by the connecting portion, the work shaft is rotated by rotating the existing main shaft to the general-purpose screw grinder. be able to. Therefore, it is not necessary to connect a separate drive motor to the work shaft in order to rotate the work shaft. As a result, the hourglass worm rolling die can be manufactured with a manufacturing apparatus having a simpler configuration.

According to the eighth aspect of the present invention, the turning operation necessary for forming the tooth gap for forming the hourglass worm on the outer peripheral surface of the work is performed by turning the work. Further, by feeding the rotating grindstone toward the workpiece along the radial direction of the workpiece, a tooth groove for forming the hourglass worm is formed. Therefore, compared with the case where only one of the workpiece and the rotating grindstone is turned and fed, the generation of the accumulated error is suppressed. Therefore, the accuracy of the manufactured hourglass worm die can be improved.

  The manufacturing apparatus is placed on a table of a general-purpose screw grinder. By using a general purpose screw grinder, there is no need to make a completely new device from scratch. Furthermore, since the manufacturing apparatus is provided with a slide table for aligning the axis of the pivot axis with the pivot center of the workpiece, the workpiece has various sizes of workpieces and outer peripheral surfaces having various curvatures. Thus, the axis of the turning axis can coincide with the turning center of the workpiece. Accordingly, a rolling die can be manufactured by processing a workpiece having outer peripheral surfaces of various sizes and various curvatures.

According to the ninth aspect of the present invention, the turning motion required to form the tooth gap for forming the hourglass worm on the outer peripheral surface of the work is performed by turning the work. Further, by feeding the rotating grindstone toward the workpiece along the radial direction of the workpiece, a tooth groove for forming the hourglass worm is formed. Therefore, compared with the case where only one of the workpiece and the rotating grindstone is turned and fed, the generation of the accumulated error is suppressed. Therefore, the accuracy of the manufactured hourglass worm die can be improved.

  Even if the swivel axis is arranged so that the axis of the swivel axis is away from the center of curvature of the outer peripheral surface of the hourglass worm rolling die formed by machining the work, A tooth groove for forming the hourglass worm is formed on the outer peripheral surface of the workpiece in the same manner as the case where the hourglass worm rolling die formed by machining is turned around the center of curvature of the outer peripheral surface. Furthermore, the manufacturing apparatus is placed on a table of a general-purpose screw grinder. By using a general purpose screw grinder, there is no need to make a completely new device from scratch.

According to the invention of claim 1 0, the axis of the pivot axis of the workpiece axis is perpendicular. Therefore, when the workpiece is fixed to the workpiece axis, the axis of the pivot axis passes through the intersection of the workpiece axis and the center line passing through the center of the workpiece in the thickness direction. And since the intersection of the workpiece axis and the center line passing through the center of the workpiece thickness direction is the point that becomes the center of the workpiece, the workpiece passes through the point where the axis of the pivot axis becomes the center of the workpiece. It is turned stably.

  In addition, if the workpiece has a diameter that can be supported by the workpiece axis, any workpiece is fixed to the workpiece axis, and the axis of the pivot axis passes through the workpiece axis and the center in the thickness direction of the workpiece. Pass the intersection with. Therefore, the tooth gap for forming the hourglass worm can be formed on the workpiece of various sizes within a range that can be supported by the workpiece shaft.

According to the invention of claim 1 1, the workpiece is driven by provided in the pivot table workpiece shaft drive motor. Therefore, when using a general-purpose screw grinder, even if it is difficult to connect a drive mechanism for rotating the workpiece to the workpiece, the workpiece can be rotated by the workpiece axis driving motor connected to the workpiece axis.

According to the invention of claim 1 2, because it connects the main shaft and the workpiece axis of universal screw grinding machine by connecting portions, by rotating the existing main shaft universal screw grinders, rotating the workpiece axis Can be made. Therefore, it is not necessary to connect a separate drive motor to the work shaft in order to rotate the work shaft. As a result, the manufacturing apparatus can be made simpler.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the rolling die for hourglass worms which can improve a precision, and the manufacturing apparatus of the rolling die for hourglass worms can be provided.

(First embodiment)
A first embodiment of the present invention will be described below with reference to the drawings.
FIG. 1 shows a drum 1 worm rolling die manufacturing apparatus 1 (hereinafter referred to as manufacturing apparatus 1). The manufacturing apparatus 1 includes a drum-shaped worm rolling die 5 (hereinafter referred to as a rolling die 5) used when forming a drum-shaped worm 4 on a worm shaft 3 provided in a motor 2 with a speed reduction mechanism shown in FIG. Device).

  First, the motor 2 will be described. As shown in FIG. 2, the motor 2 includes a motor body 11, a speed reduction unit 12, and a clutch 13. The motor 2 includes a yoke 14 having a substantially bottomed flat cylindrical shape, and a magnet 15 is fixed to the inner peripheral surface of the yoke 14. An armature 16 is rotatably accommodated inside the magnet 15. The armature 16 has a rotating shaft 17, and a commutator 18 is fixed to the opening side of the yoke 14 of the rotating shaft 17. A brush holder 20 having a brush 19 that is in sliding contact with the commutator 18 is fitted in the opening of the yoke 14.

  When driving power is supplied to the motor body 11 from the outside, the driving power is supplied to the winding wound around the armature 16 via the brush 19 and the commutator 18. The armature 16 (rotary shaft 17) rotates, that is, the motor main body 11 is driven to rotate based on the supply of drive power.

The speed reduction unit 12 includes a gear housing 21, a worm shaft 3 and a worm wheel 22 accommodated in the gear housing 21, and an output shaft 23.
As shown in FIG. 3A, the worm shaft 3 includes a worm shaft main body 3a and a driven side rotating body 3b integrally formed at the end of the worm shaft main body 3a on the motor main body 11 side (FIG. 2). reference). The hourglass worm 4 is formed in the axial center of the worm shaft main body 3a. The hourglass worm 4 includes an hourglass-shaped core portion 4a whose outer diameter decreases toward the center, and a tooth portion 4b having an advance angle α is integrated with the core portion 4a on the outer periphery of the core portion 4a. Is formed. As shown in FIG.3 (b), the outer periphery of the core part 4a, ie, the shape of the tooth bottom of the tooth part 4b, is circular arc shape determined by the curvature radius R1 of the curvature center O1.

  As shown in FIG. 2, the worm wheel 22 is accommodated in the gear housing 21 so as to mesh with the hourglass worm 4. An output shaft 23 that is coaxial with the worm wheel 22 and integrally rotates is connected to the central portion of the worm wheel 22. The output shaft 23 is connected to a window regulator (not shown) that opens and closes a window glass of the vehicle, for example.

  Such a motor main body 11 and the speed reduction part 12 are connected by fixing the yoke 14 to the gear housing 21. The rotating shaft 17 of the armature 16 and the worm shaft 3 are connected via a clutch 13. The clutch 13 includes a drive-side rotator 24 fixed to the tip of the rotating shaft 17 on the speed reduction unit 12 side, and the driven-side rotator 3b. Then, the clutch 13 transmits the rotation of the driving side rotating body 24 by driving the motor main body 11 to the driven side rotating body 3 b to rotate the worm shaft 3. The rotation is decelerated between the hourglass worm 4 and the worm wheel 22 and output from the output shaft 23 to the window regulator. Further, the clutch 13 serves to prevent the rotation of the output shaft 23 by locking the driven-side rotator 3b when a load is applied to rotate the output shaft 23 from the window regulator side while the motor 2 is stopped. Plays.

  Next, the rolling die 5 will be described. As shown in FIG. 4A, the rolling die 5 has a disc shape. The axial thickness of the rolling die 5 is formed to be equal to the axial length of the hourglass worm 4. As shown in FIG. 4B, the outer peripheral surface 5a of the rolling die 5 passes through the axis L1 of the rolling die 5 and is in the arbitrary surface S1 along the radial direction, the hourglass worm 4 It is formed in the circular arc shape of the curvature radius R2 equal to the curvature radius R1 of the root surface of the tooth part 4b. A plurality of tooth grooves 5b formed corresponding to the shape of the tooth portion 4b of the hourglass worm 4 are formed on the outer peripheral surface 5a. The tooth grooves 5b are arranged in the axial direction of the rolling die 5 (in the direction of the axis L1) for each pitch corresponding to the pitch of the hourglass worm 4. When the hourglass worm 4 is brought into contact with the outer peripheral surface 5 a of the rolling die 5, the curvature center O1 of the bottom curved surface of the tooth portion 4 b of the hourglass worm 4 and the curvature of the outer peripheral surface 5 a of the rolling die 5 are obtained. The center O2 coincides.

  Next, the configuration of the manufacturing apparatus 1 will be described. As shown in FIG. 1, the manufacturing apparatus 1 includes a turning table 31, a slide table 32, a work shaft 33, and a rotating grindstone 34. The manufacturing apparatus 1 is placed on a table 37 of a general-purpose screw grinding machine 36 (see FIG. 7).

  As shown in FIG. 5, the turning table 31 is placed on a table 37 of a general-purpose screw grinding machine 36 so as to be turnable. Specifically, a through hole 37 a is formed in the table 37. A bearing 38 is fixed inside the through hole 37a. A turning shaft 39 that is rotatably supported by a bearing 38 is fitted into the through hole 37a. A turning table 31 is fixed to the upper end portion of the turning shaft 39 with a screw 40. A reduction gear group 44 formed by meshing a plurality of gears 41 to 43 is disposed below the table 37. The first gear 41 of the reduction gear group 44 is connected to the turning shaft drive motor 45 (see FIG. 6), and the third gear 43 and the turning shaft 39 rotate integrally with the final third gear 43. In this way, it is connected to the lower end of the turning shaft 39. Therefore, when the turning shaft drive motor 45 is driven, the rotation reduced by the reduction gear group 44 is transmitted to the turning shaft 39. By the rotation, the turning shaft 39 is turned and the turning table 31 is turned together with the turning shaft 39.

  A slide table 32 is placed on the upper surface of the turntable 31 via a slide mechanism 51. The slide mechanism 51 is a ball screw that includes a screw shaft 51a and a nut portion 51b that is slidably connected to the screw shaft 51a. The screw shaft 51 a is disposed on the upper part of the turning table 31 in parallel with the turning table 31. A holding member 52 is fixed on the turntable 31, and a bearing 53 is fixed inside the holding member 52. One end of the screw shaft 51a is rotatably supported by a bearing 53, and the other end is connected to a slide table drive motor 54 (see FIG. 6).

  The slide table 32 is fixed to the upper portion of the nut portion 51b so as to be parallel to the turning table 31, and moves integrally with the nut portion 51b. Therefore, when the slide table drive motor 54 is driven, the screw shaft 51a is rotated according to the drive direction. When the screw shaft 51a rotates, the nut portion 51b is slid in the direction corresponding to the rotation direction along the axial direction of the screw shaft 51a. When the nut portion 51b is slid, the slide table 32 moves integrally with the nut portion 51b.

  A pair of support members 61 and 62 (see FIG. 1) is fixed to the upper surface of the slide table 32, and the work shaft 33 is supported by the support members 61 and 62. The support members 61 and 62 are erected on the slide table 32 so as to face each other at a predetermined interval. The work shaft 33 is rotatably supported at two locations by support members 61 and 62, and is disposed in parallel to the slide table 32 and orthogonal to the axis L2 of the screw shaft 51a. A work shaft drive motor 63 is connected to one end of the work shaft 33 via a speed reducer 64 (see FIG. 6). A workpiece 70 (see FIG. 1) serving as the rolling die 5 is fixed to the workpiece shaft 33 between the support members 61 and 62. When the work shaft drive motor 63 is driven, the rotation decelerated by the speed reducer 64 is transmitted to the work shaft 33. Then, the work 70 rotates together with the work shaft 33.

  As shown in FIG. 1, the rotating grindstone 34 has a disk shape. And the grinding part 34a whose outer peripheral part makes the shape similar to the shape of the tooth | gear part 4b of the hourglass worm 4 is formed. Such a rotating grindstone 34 is supported by a grindstone shaft 73 fixed to a grindstone base 72 (see FIG. 6) so as to be integrally rotatable with the grindstone shaft 73. Further, a grindstone drive motor 74 (see FIG. 6) is connected to the grindstone shaft 73, and when the grindstone drive motor 74 is driven, the grindstone shaft 73 rotates and the rotating grindstone 34 rotates. It has become. A grindstone shaft drive motor 75 is connected to the grindstone shaft 73 (see FIG. 6). The grindstone shaft drive motor 75 is for turning the rotating grindstone 34 in order to incline the axis L4 of the rotating grindstone 34 by the advance angle α of the hourglass worm 4 with respect to the axis L3 of the workpiece 70. (See FIG. 8 (b)).

  The grindstone base 72 is arranged so that the rotating grindstone 34 fixed to the grindstone shaft 73 contacts the outer peripheral surface 70 a of the work 70 from the outside in the radial direction of the work 70. The grinding wheel base 72 is provided with a grinding wheel base driving motor 76 (see FIG. 6). When the grinding wheel base driving motor 76 is driven, the grinding wheel base 72 moves along the radial direction of the workpiece 70, The rotating grindstone 34 is fed to the work 70 side along the radial direction of the work 70.

FIG. 6 shows a block diagram when the manufacturing apparatus 1 is applied to the general-purpose screw grinding machine 36. Here, first, the configuration of the general-purpose screw grinder 36 will be described.
As shown in FIG. 7, the general-purpose screw grinding machine 36 includes a numerical control board 81 as a synchronizing means. The numerical control panel 81 is connected to a spindle drive motor 82, a table drive motor 83, the grindstone drive motor 74, the grindstone shaft drive motor 75, and the grindstone table drive motor 76.

  A main shaft for rotating the workpiece 85 is connected to the main shaft driving motor 82. Then, the spindle drive motor 82 is rotated in accordance with a signal output from the numerical control panel 81, and the spindle, that is, the work 85 is rotated. The spindle drive motor 82 includes an encoder 86, and the encoder 86 outputs a signal corresponding to the rotation state of the spindle drive motor 82 to the numerical control panel 81. The numerical control panel 81 detects the rotational state such as the rotational speed, rotational speed, and rotational position of the spindle drive motor 82 based on this signal, and controls the spindle drive motor 82.

  A table 37 to which the work 85 is fixed is connected to the table drive motor 83. Then, the table drive motor 83 is rotated in accordance with a signal output from the numerical control panel 81, and the table 37 is moved. The table drive motor 83 is provided with an encoder 87, and the encoder 87 outputs a signal corresponding to the rotation state of the table drive motor 83 to the numerical control panel 81. The numerical control panel 81 detects the rotation state such as the rotation speed, rotation speed, and rotation position of the table drive motor 83 based on this signal, and controls the table drive motor 83. The table 37 is provided with a linear scale 88, and the linear scale 88 outputs a signal for detecting the position of the table 37 to the numerical control panel 81. Based on this signal, the numerical control panel 81 detects the position of the table 37.

  A grinding wheel base 72 is connected to the grinding wheel base driving motor 76. Then, the grindstone table driving motor 76 is rotated in accordance with a signal output from the numerical control panel 81, and the grindstone table 72 is moved by the rotation, so that the rotating grindstone 91 for processing the workpiece 85 is sent to the workpiece 85 side. . Further, the wheel head drive motor 76 is provided with an encoder 89, and the encoder 89 outputs a signal corresponding to the rotation state of the wheel head drive motor 76 to the numerical control panel 81. The numerical control panel 81 detects the rotation state such as the rotation speed, rotation speed, and rotation position of the wheel head drive motor 76 based on this signal, and controls the wheel head drive motor 76. Further, the grinding wheel base 72 is provided with a linear scale 90, and the linear scale 90 outputs a signal for detecting the position of the grinding wheel base 72 to the numerical control panel 81. Based on this signal, the numerical control panel 81 detects the position of the grindstone table 72 and controls the amount of feeding the rotating grindstone 91 to the work 85 side.

  The grindstone drive motor 74 is connected to the numerical control panel 81 via the inverter 92. A rotating grindstone 91 is connected to the grindstone drive motor 74 via a grindstone shaft 73. Then, the inverter 92 rotates the grindstone driving motor 74 in accordance with a signal output from the numerical control panel 81, and the grindstone shaft 73, that is, the rotating grindstone 91 is rotated by the rotation.

  A grindstone shaft 73 is connected to the grindstone shaft drive motor 75. Then, the grindstone shaft driving motor 75 is rotated in accordance with a signal output from the numerical control panel 81, and the rotating grindstone 91 is turned by the rotation angle of the worm that is processed into the workpiece 85 by the rotation. Further, the grindstone shaft drive motor 75 is provided with an encoder 93, and outputs a signal corresponding to the rotation state of the grindstone shaft drive motor 75 to the numerical control panel 81. The numerical control panel 81 detects the rotation state such as the rotation speed, rotation speed, and rotation position of the grindstone shaft drive motor 75 based on this signal, and controls the grindstone shaft drive motor 75.

  In the general-purpose screw grinding machine 36 configured as described above, in this embodiment, a work axis drive motor 63 is connected to a numerical control board 81 instead of the main spindle drive motor 82 as shown in FIG. Further, the turning shaft drive motor 45 and the slide table drive motor 54 are connected to the numerical control panel 81. The work axis drive motor 63, the turning axis drive motor 45, and the slide table drive motor 54 are connected to an empty control axis existing on the numerical control panel 81. Therefore, in this embodiment, in the general-purpose screw grinder 36, the portion surrounded by the broken line shown in FIG. 7 is replaced with the portion (manufacturing apparatus 1) surrounded by the broken line shown in FIG. The work shaft drive motor 63, the turning shaft drive motor 45, and the slide table drive motor 54 are provided with encoders 95, 96, and 97, respectively, and the numerical control panel 81 includes the drive motors 63, 45, and 54. A signal corresponding to the rotation state is output. The numerical control panel 81 detects and controls the rotation state of each drive motor 63, 45, 54 based on these signals.

Next, a method of manufacturing the rolling die 5 for rolling the hourglass worm 4 using the general-purpose screw grinding machine 36 provided with the manufacturing apparatus 1 will be described.
First, the workpiece | work 70 used as the rolling die 5 is demonstrated. As shown in FIGS. 8A and 8B, the work 70 has a disk shape. The axial thickness of the work 70 is formed to be equal to the axial length of the hourglass worm 4. The outer peripheral surface 70a of the work 70 is equal to the radius of curvature R1 of the bottom curved surface of the tooth portion 4b of the hourglass worm 4 in an arbitrary surface S2 passing through the axis L3 of the work 70 and extending in the radial direction. It is formed in an arc shape with a radius of curvature R3. That is, the outer peripheral surface 70a of the work 70 of the present embodiment is bulged so as to have an arc shape with a curvature equal to the curvature of the outer peripheral surface 5a of the rolling die 5 formed by processing the work 70.

  Next, a method for manufacturing the rolling die 5 will be described. As shown in FIG. 1, the work 70 is fixed to the work shaft 33. Then, as shown in FIG. 2, the numerical control panel 81 drives the slide table drive motor 54 to slide the slide table 32, passes through the axis L <b> 3 of the work 70 and is parallel to the turning table 31, The axis L5 of the turning shaft 39 and the center of curvature O3 of the outer peripheral surface 70a of the work 70 are made to coincide. In addition, as shown in FIGS. 8A and 8B, the numerical control panel 81 is inclined with respect to the axis L3 of the workpiece 70 by the advance angle α of the hourglass worm 4 with respect to the axis L4 of the rotating grindstone 34. Thus, the grindstone shaft drive motor 75 is driven to rotate the grindstone shaft 73.

  Thereafter, the numerical control panel 81 rotates the work 70 and the rotating grindstone 34 by driving the work shaft drive motor 63 and the grindstone drive motor 74. At this time, the numerical control panel 81 causes the turning table 31 to turn in the thickness direction of the work 70 around the center of curvature O3 coincident with the axis L5 of the turning shaft 39 in synchronization with the rotation of the work 70. In addition, the rotation of the work axis drive motor 63 and the turning axis drive motor 45 is controlled. Then, the grindstone drive motor 76 is driven to feed the rotating grindstone 34 toward the workpiece 70 along the radial direction of the workpiece 70.

  In this way, the workpiece 70 is reciprocated in the thickness direction of the workpiece 70 while keeping the axis L4 of the rotating grindstone 34 to be inclined by the advance angle α of the hourglass worm 4 with respect to the axis L3 of the workpiece 70. The tooth groove 5b for forming the hourglass worm 4 is formed on the outer peripheral surface of the work 70 by rotating the work 70 forward and backward.

  And in order to manufacture the worm shaft 3 provided with the hourglass worm 4 using the rolling dies 5 manufactured by the above manufacturing method, as shown in FIG. 9A, a pair of rolling dies 5 is used. The worm shaft 3 before the hourglass worm 4 is formed is disposed between the two. At this time, the rolling die 5 and the worm shaft 3 are positioned so that the axis L1 of the pair of rolling dies 5 and the axis L7 of the worm shaft 3 are located in the same plane. Then, as shown in FIG. 9B, the worm shaft 3 and the pair of rolling dies 5 are forcibly rotated synchronously with the worm shaft 3 fixed so as not to move in the axial direction. At this time, the pair of rolling dies 5 are rotated in the same direction. Thus, the hourglass worm 4 of the worm shaft 3 is formed.

As described above, the first embodiment has the following effects.
(1) The turning operation necessary to form the tooth groove 5b for forming the hourglass worm 4 on the outer peripheral surface of the work 70 is performed by turning the work 70. Further, by feeding the rotating grindstone 34 along the radial direction of the workpiece 70 to the workpiece 70 side, a tooth groove 5b for forming the hourglass worm 4 is formed. Therefore, compared with the case where only one of the workpiece 70 and the rotating grindstone 34 is turned and fed, the generation of the accumulated error can be suppressed. Therefore, the accuracy of the manufactured hourglass worm rolling die 5 can be improved. As a result, the accuracy of the hourglass worm 4 manufactured using the rolling die 5 can be improved.

  (2) The manufacturing apparatus 1 is fixed to the table 37 of the general-purpose screw grinder 36. By using the general-purpose screw grinder 36, it is not necessary to make a completely new device. Therefore, an increase in manufacturing cost of the manufacturing apparatus 1 can be prevented.

  (3) Since the manufacturing apparatus 1 includes the slide table 32 for matching the axis L5 of the turning shaft 39 and the turning center (curvature center O3) of the work 70, the work 70, which has various sizes, Further, with respect to the workpiece 70 having the outer peripheral surface 70a with various curvatures, the axis L5 of the turning shaft 39 and the turning center of the workpiece 70 can be matched. Therefore, the rolling die 5 can be manufactured by processing the workpiece 70 having various sizes and the curvature radii R3 of various sizes. In addition, the slide table 32 is slid so that the axis L5 of the turning shaft 39 and the center of curvature O3 of the outer peripheral surface 70a of the work 70 coincide with each other in the surface S3, so that the turning center O3 can be easily turned around the turning center. Can do.

  (4) The work shaft 33 is driven by a work shaft drive motor 63 provided in the turning table 31. Therefore, when using the general-purpose screw grinder 36, even if it is difficult to connect the work shaft 33 to a drive mechanism (for example, a main shaft) that rotates the work shaft 33, the work shaft drive motor connected to the work shaft 33 is used. 63, the work shaft 33 can be rotated.

  (5) The workpiece axis drive motor 63, the turning axis drive motor 45, and the slide table drive motor 54 are connected to an existing empty control axis in the numerical control panel 81. Therefore, the manufacturing apparatus 1 can be operated without modifying the numerical control panel 81 in order to drive the work axis drive motor 63, the turning axis drive motor 45, and the slide table drive motor 54.

(Second Embodiment)
Hereinafter, a second embodiment of the present invention will be described with reference to the drawings. In addition, about the structure same as the said 1st Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  FIG. 10 shows an apparatus 200 for manufacturing a drum-shaped worm rolling die (hereinafter referred to as manufacturing apparatus 200). As in the manufacturing apparatus 1 of the first embodiment, the manufacturing apparatus 200 includes a rolling die 5 used for forming the hourglass worm 4 on the worm shaft 3 shown in FIGS. 3 (a) and 3 (b). It is a device to manufacture.

  As shown in FIG. 10, the manufacturing apparatus 200 includes a turning table 31, a work shaft 33, and a rotating grindstone 34. In the second embodiment, the table 37 of the general-purpose screw grinding machine 36 (see FIG. 7) also constitutes the manufacturing apparatus 200. And the manufacturing apparatus 200 of this 2nd Embodiment becomes a structure without the slide table 32 and the slide mechanism 51 (refer FIG. 5) compared with the manufacturing apparatus 1 of the said 1st Embodiment.

  As shown in FIG. 12, the table 37 is slid by the slide mechanism 201 provided in the general-purpose screw grinding machine 36. The slide mechanism 201 includes a guide rail 202 provided along a direction orthogonal to the moving direction of the grindstone table 72 (see FIG. 13) (the direction in which the rotating grindstone 34 is fed). A guide groove 203 that is engaged with the guide rail 202 is formed on the lower end surface of the table 37. Further, a nut portion of a ball screw (not shown) constituting the slide mechanism 201 is fixed to the table 37. One end of the screw shaft into which the nut portion is screwed is connected to a table drive motor 83 (see FIG. 13). Therefore, when the table drive motor 83 is driven, the screw shaft is rotated according to the drive direction, and the nut portion is moved according to the rotation direction of the screw shaft. Thereby, the table 37 is slid and moved together with the nut portion while being guided by the guide rail 202. That is, when the drive motor 83 is driven, the table 37 is slid along the direction orthogonal to the movement direction of the grindstone 72nd. The turning table 31 and the reduction gear group 44 placed on the table 37 are also slid together with the table 37.

  As shown in FIGS. 10 and 12, in the second embodiment, the support members 61 and 62 are fixed to the upper surface of the turning table 31. The support members 61 and 62 are erected on the turntable 31 so as to face each other with a certain interval. The work shaft 33 is supported by these support members 61 and 62. In the second embodiment, the work shaft 33 is supported by the support members 61 and 62 so that the work shaft 33 is parallel to the turning table 31 and the axis L8 of the work shaft 33 is orthogonal to the axis L5 of the turning shaft 39. It is rotatably supported. An intersection P1 (see FIG. 10) between the axis L8 of the work shaft 33 and the axis L5 of the turning shaft 39 is located at the center between the support members 61 and 62. When the turning table 31 is not turning, the axis L8 of the workpiece shaft 33 is parallel to the sliding direction of the table 37 (longitudinal direction of the guide rail 202). When the workpiece 70 is fixed to the workpiece shaft 33 supported by the support members 61 and 62 in this way, the axis L8 of the workpiece shaft 33 and the axis L3 of the workpiece 70 coincide. Further, when the work 70 is fixed to the work shaft 33, the axis L5 of the turning shaft 39 passes through the intersection P2 of the axis L3 of the work 70 and the center line L9 passing through the center of the work 70 in the thickness direction. That is, in the present embodiment, the intersection point P1 and the intersection point P2 coincide (see FIG. 11). Therefore, when the turning shaft drive motor 45 is driven and the turning shaft 39 is turned, the work 70 is turned around the intersection P2 between the axis L3 and the center line L9 of the work 70 as a turning center.

  As shown in FIG. 13, the numerical control panel 81 of the second embodiment corresponds to the rotation state of each drive motor 45, 63, 76, 75, 83 input from encoders 87, 89, 93, 95, 96. Based on the received signal, the rotation state of each drive motor 45, 63, 76, 75, 83 is detected, and each drive motor 45, 63, 76, 75, 83 is controlled. The numerical control panel 81 detects the positions of the table 37 and the grindstone table 72 based on signals input from the linear scales 88 and 90, and the table 37 based on the detected positions of the table 37 and the grindstone table 72. The amount by which the rotary whetstone 91 is slid and the amount by which the rotary grindstone 91 is fed to the work 70 side is controlled.

  Here, the position control of the work 70 and the rotating grindstone 34 performed by the numerical control panel 81 will be described with reference to FIGS. The numerical control panel 81 rotates with the work 70 when the relative position of the work 70 that is turned about the turning point P2 and the rotating grindstone 34 is turned about the center of curvature O3 of the outer peripheral surface 70a of the work 70. The positions of the work 70 and the rotating grindstone 34 are controlled according to the rotation amount of the work 70 so as to be the same as the relative position with the grindstone 34. Incidentally, the relative position between the work 70 and the rotating grindstone 34 means the relative position of the rotating grindstone 34 with respect to the work 70 that is changed according to the rotation of the work 70.

  Assuming that the rotation amount (rotation angle) of the workpiece 70 is θ, the rotation of the workpiece 70 (rotation of the rotation shaft 39) is performed in synchronization with the rotation of the workpiece 70 (rotation of the workpiece shaft 33) as in the above embodiment. Therefore, the turning amount (turning angle) of the work 70 is a function of the rotation amount θ of the work 70. Therefore, the turning amount of the work 70 is expressed as B (θ) [°]. The turning amount B (θ) of the work 70 is based on the position of the work 70 before the work 70 is turned, that is, when the work 70 is fixed to the work shaft 30 (B (θ) = 0). Is an angle.

  FIG. 14 shows a workpiece 70 (shown by a solid line in FIG. 14) fixed to the workpiece shaft 30 (before turning) and a counterclockwise direction from the state fixed to the workpiece shaft 30 with the intersection P2 as the turning center. The workpiece 70 (indicated by a two-dot chain line in FIG. 14) in a state of being turned by B (θ) is shown. As shown in FIG. 14, when the work 70 is turned by B (θ) in the counterclockwise direction around the intersection P2 as the turning center, the relative position of the rotating grindstone 34 with respect to the work 70 turns around the center of curvature O3 as the turning center. In this case, the relative position between the work 70 and the rotating grindstone 34 is set to be the same. At this time, the rotating grindstone 34 is arranged at a position shifted by B (θ) in the clockwise direction with respect to the workpiece 70 around the center of curvature O3. However, in this embodiment, since the rotating grindstone 34 cannot move in the left-right direction (direction orthogonal to the direction in which the rotating grindstone 34 is fed) in FIG. 14, the workpiece 70 is relatively swiveled as shown in FIG. The left and right direction components (components in the direction orthogonal to the direction in which the rotating grindstone 34 is fed) Δz (θ) of the moving amount between the previous center of curvature O3 and the center of curvature O4 after turning are moved. Further, in addition to the feed amount x (θ) when the workpiece 70 is turned about the center of curvature O3, the vertical component (rotation) of the amount of movement between the center of curvature O3 before turning and the center of curvature O4 after turning. The rotating grindstone 34 is moved by a component (Δx (θ) in the direction in which the grindstone 34 is fed). The vertical component Δx (θ) and the horizontal component Δz (θ) are expressed as follows using the turning amount B (θ) and the distance D between the intersection P2 and the center of curvature O3. The

Δx (θ) = D · (1-cosB (θ))
Δz (θ) = D · sinB (θ)
The numerical control panel 81 calculates Δx (θ) and Δz (θ) based on the above equation based on the turning amount B (θ) of the work 70 and calculates the amount according to the turning amount B (θ) of the work 70. The rotary grindstone 34 is fed to the workpiece 70 side by x (θ) + Δx (θ), and the workpiece 70 is slid by Δz (θ) along the direction orthogonal to the direction in which the rotary grindstone 34 is fed. At this time, the center of curvature O3 is moved by Δx (θ) along the direction in which the rotating grindstone 34 is fed. Further, the intersection point P2 is moved by Δz (θ) along the direction orthogonal to the direction in which the rotating grindstone 34 is fed (in FIG. 15, the moved intersection point P2 is shown as P3). 16A shows a graph showing the relationship between the rotation amount θ of the work 70 and the turning amount B (θ) of the work 70, and FIG. 16B shows the rotation amount θ of the work 70 and the rotating grindstone 34. FIG. 16C shows a graph showing the relationship between the amount x (θ) + Δx (θ) to be fed, and FIG. 16C shows the relationship between the rotation amount θ of the workpiece 70 and the amount Δz (θ) by which the workpiece 70 is slid. A graph is shown.

Next, a method for manufacturing the rolling die 5 using the manufacturing apparatus 200 described above will be described.
First, as shown in FIG. 10, the work 70 is fixed to the work shaft 33. Thereby, the axis L5 of the turning shaft 39 passes through the intersection P2 between the axis L3 of the workpiece 70 and the center line L9 passing through the center of the workpiece 70 in the thickness direction (see FIG. 11). Then, as shown in FIG. 8B, the numerical control panel 81 is configured such that the axis L4 of the rotating grindstone 34 is inclined by the advance angle α of the hourglass worm 4 with respect to the axis L3 of the work 70. The grindstone shaft drive motor 75 is driven to turn the grindstone shaft 73.

  Thereafter, the numerical control panel 81 rotates the work 70 and the rotating grindstone 34 by driving the work shaft drive motor 63 and the grindstone drive motor 74. At this time, the numerical control panel 81 controls the rotation of the work axis drive motor 63 and the rotation axis drive motor 45 so that the rotation table 31 is rotated in synchronization with the rotation of the work 70. The numerical control panel 81 detects the turning amount B (θ) of the workpiece 70 based on a signal input from the encoder 96 provided in the turning shaft drive motor 45. Then, the numerical control panel 81 drives the table drive motor 83 and the grindstone base drive motor 76 according to the detected turning amount B (θ) of the work 70 to move the table 37 by Δz (θ) and The stage 72 is moved by x (θ) + Δx (θ). As a result, the rotary grindstone 34 is fed toward the workpiece 70 by x (θ) + Δx (θ), and the workpiece 70 is slid by Δz (θ). Accordingly, when the relative position of the work 70 and the rotating grindstone 34 according to the amount of rotation of the work 70 that is turned about the turning point P2 is turned about the center of curvature O3 of the outer peripheral surface 70a of the work 70 as a turning center. The relative position between the work 70 and the rotating grindstone 34 according to the rotation amount of the work 70 is the same.

  In this way, the workpiece 70 is reciprocated in the thickness direction of the workpiece 70 while keeping the axis L4 of the rotating grindstone 34 to be inclined by the advance angle α of the hourglass worm 4 with respect to the axis L3 of the workpiece 70. The tooth groove 5b for forming the hourglass worm 4 is formed on the outer peripheral surface of the work 70 by rotating the work 70 forward and backward.

As described above, the second embodiment has the following effects in addition to the effects (1) and (4) of the first embodiment.
(1) The numerical control panel 81 is configured so that the relative position between the work 70 turned about the turning point P2 and the rotating grindstone 34 is turned about the center of curvature O3 of the outer peripheral surface 70a of the work 70 as the turning center. The positions of the work 70 and the rotating grindstone 34 are controlled in accordance with the rotation amount θ of the work 70 so as to be the same as the relative position between the 70 and the rotating grindstone 34. Accordingly, the axis L5 of the turning shaft 39 is arranged so as to pass through the intersection P2 between the axis L3 of the workpiece 70 and the center line L9 passing through the center of the workpiece 70 in the thickness direction, and the workpiece 70 is turned around the intersection P2 as the turning center. Even in this case, the tooth groove 5b for forming the hourglass worm 4 is formed on the outer peripheral surface 70a of the work 70, as in the case of turning around the center of curvature O3 as the turning center.

  (2) The intersection P2 between the axis L3 of the work 70 and the center line L9 passing through the center of the work 70 in the thickness direction is a point that is the center of the work 70. Since the axis L5 of the turning shaft 39 passes through the point that is the center of the work 70, the work 70 is turned more stably. As a result, the accuracy of the rolling die 5 manufactured by the manufacturing apparatus 200 can be further improved.

  (3) In the manufacturing apparatus 200, the axis L8 of the work shaft 33 and the axis L5 of the turning shaft 39 are orthogonal to each other. Therefore, when the workpiece 70 is fixed to the workpiece shaft 33, the axis L5 of the turning shaft 39 passes through the intersection P2 between the axis L3 of the workpiece 70 and the center line L9 passing through the center of the workpiece 70 in the thickness direction. Accordingly, as in the manufacturing apparatus 1 of the first embodiment, the slide table 32 is slid and passes through the axis L3 of the work 70, and in the plane S3 parallel to the turning table 31, the axis L5 of the swivel shaft 39 and the work 70 It is not necessary to match the curvature center O3 of the outer peripheral surface 70a. As a result, the manufacturing time of the rolling die 5 can be shortened.

  In addition, as long as the workpiece 70 has a diameter that can be supported by the workpiece shaft 33, any workpiece 70 is fixed to the workpiece shaft 33, the axis L 5 of the turning shaft 39 is changed between the axis L 3 of the workpiece 70 and the workpiece 70. It passes through the intersection P2 with the center line L9 passing through the center in the thickness direction. Accordingly, the tooth groove 5b for forming the hourglass worm 4 on the outer peripheral surface 70a of the workpiece 70 having various sizes within the range that can be supported by the workpiece shaft 33 and the outer peripheral surface 70a having various curvatures. Can be formed.

Furthermore, in the manufacturing apparatus 200, when the axis L8 of the work shaft 33 and the axis L5 of the turning shaft 39 are orthogonal to each other, the manufacturing apparatus 200 can be easily assembled.
(4) The manufacturing apparatus 200 of the second embodiment has a configuration without the slide table 32 provided in the manufacturing apparatus 1 of the first embodiment. Therefore, the manufacturing apparatus 200 can reduce the size of the apparatus by the amount of the slide table 32 as compared with the manufacturing apparatus 1 of the first embodiment. In addition, when the manufacturing apparatus 200 is approximately the same size as the manufacturing apparatus 1, a larger rolling die 5 can be manufactured as much as there is no slide table 32. Further, since there is no slide table 32, the manufacturing apparatus 200 has a simpler configuration than the manufacturing apparatus 1 of the first embodiment, and maintenance is easier than the manufacturing apparatus 1.

  (5) The workpiece axis drive motor 63 and the turning axis drive motor 45 are connected to an existing empty control axis in the numerical control panel 81. Therefore, the manufacturing apparatus 1 can be operated without modifying the numerical control panel 81 in order to drive the work axis drive motor 63, the turning axis drive motor 45, and the slide table drive motor 54.

  (6) The numerical control panel 81 detects the positions of the grindstone table 72 and the table 37 that are moved during the processing of the workpiece 70 based on the signals input from the linear scale 88 and the linear scale 90, and at the detected positions. Based on this, the table drive motor 83 and the wheel head drive motor 76 are controlled. Accordingly, not only the signals input from the encoders 87 and 89 for detecting the rotation state of the table drive motor 83 and the grindstone table drive motor 76 but also the positions of the table 37 and the grindstone table 72 to be moved are directly measured by the linear scales 88 and 90. By detecting, the numerical control panel 81 can perform the position control of the table 37 and the grindstone table 72 at a higher level. As a result, the accuracy of the rolling die 5 manufactured by the manufacturing apparatus 200 can be further improved.

  (7) By turning around the intersection P2 as the turning center, the turning angle of the work 70 becomes smaller than when turning around the center of curvature O3 of the outer peripheral surface 70a of the work 70 as the turning center. Therefore, the manufacturing time of the rolling die 5 can be further shortened.

In addition, you may change embodiment of this invention as follows.
In the first and second embodiments, the work shaft 33 is rotated by the work shaft drive motor 63 provided in the turning table 31, but the present invention is not limited to this. For example, as shown in FIG. 7, the main shaft of the general-purpose screw grinding machine 36 and the work shaft 33 may be connected by a connecting portion 100 such as a universal joint. If comprised in this way, in order to rotate the work shaft 33, it is not necessary to connect the work shaft drive motor 63 separately. As a result, the hourglass worm rolling die 5 can be manufactured by the manufacturing apparatus 1 having a simpler configuration.

  In the first and second embodiments, the manufacturing apparatus 1,200 is fixed to the table 37 of the general-purpose screw grinding machine 36, but is not limited thereto. For example, a dedicated device may be manufactured to operate the manufacturing device 1.

  In the first and second embodiments, the numerical control panel 81 is used as a synchronizing means for synchronizing the rotation of the work shaft 33 and the turning of the turning shaft 39. However, the present invention is not limited to this. For example, the rotation of the work shaft 33 and the turning of the turning shaft 39 may be synchronized by combining gears.

  In the first and second embodiments, the rotational speed of the grindstone drive motor 74 that rotates the grindstones 34 and 91 is controlled by the inverter 92. However, the present invention is not limited to this, and the grindstone drive motor 74 is a motor having an encoder similar to the grindstone table drive motor 76 and the like, and numerical control is performed based on a signal corresponding to the rotation state of the grindstone drive motor 74 output from the encoder. It is good also as a structure which the board | substrate 81 performs control according to the rotation state of the grindstone drive motor 74. FIG.

  In the second embodiment, the work 70 is turned around the intersection P2 between the axis L3 of the work 70 and the center line L9 passing through the center of the work 70 in the thickness direction, but the present invention is not limited to this. The work 70 may be turned around a position away from the center of curvature O3 of the outer peripheral surface 70a of the work 70 as a turning center. That is, the turning shaft 39 may be arranged such that the axis L5 of the turning shaft 39 is located away from the center of curvature O3 of the outer peripheral surface 70a of the workpiece 70. Also in this case, the numerical control panel 81 is configured so that the relative position between the work 70 that is turned around the turning center at a position away from the center of curvature O3 and the rotating grindstone 34 is turned around the center of curvature O3 as the turning center. The positions of the work 70 and the rotating grindstone 34 are controlled in accordance with the rotation amount θ of the work 70 so as to be the same as the relative position between the rotating grindstone 34 and the rotating grindstone 34. If comprised in this way, the freedom degree of the arrangement position of the rotating shaft 39 will increase. When the turning shaft 39 is disposed so that the center line L9 passing through the center of the workpiece 70 in the thickness direction and the axis L5 of the turning shaft 39 are orthogonal to each other, the table 37 and the rotating grindstone 34 performed by the numerical control panel 81 are arranged. It becomes easy to control the position. In addition, the numerical control panel 81 performs an operation so that the relative position between the work 70 and the rotating grindstone 34 is the same when the work 70 is turned around the center of curvature O3 of the outer peripheral surface 70a of the work 70 as the turning center. And the feed amount of the rotating grindstone 34 are controlled. For this reason, the notch for inserting the worm shaft 3 before forming the hourglass worm 4 is formed on the outer periphery without changing the manufacturing apparatus 200 as a whole only by changing the calculation contents performed in the numerical control panel 81. Can be produced.

  In each of the above embodiments, the work 70 has an arc shape in which the outer peripheral surface 70a bulges with the same curvature as the curved surface of the bottom of the hourglass worm 4, but the shape of the work 70 is not limited to this. . The workpiece 70 only needs to have a disk shape, and may be a columnar shape or the like. In this case, the turning center of the work 70 is set based on the center of curvature of the outer peripheral surface 5a of the rolling die 5 formed by processing the work 70.

The technical ideas that can be grasped from each of the above embodiments and each of the above modifications are described below.
(B) Rotating a work having a disk shape and having an outer peripheral surface bulging in an arc shape equal to the curvature of the root surface of the hourglass worm, and rotating the axis of the hourglass worm with respect to the axis of the work by the advance angle of the hourglass worm A method of manufacturing a hourglass worm rolling die for forming a tooth groove for forming the hourglass worm on an outer peripheral surface of the workpiece with an inclined rotating grindstone, wherein the workpiece is Synchronously with the rotation of the workpiece, the drum is turned about the center of curvature of the outer peripheral surface of the workpiece as a turning center, and the rotating grindstone is fed to the workpiece side along the radial direction of the workpiece. A manufacturing method for rolling dies.

  (B) A turning table placed on a table of a general-purpose screw grinder and turned on a turning shaft, and a curvature of the root surface of a drum-shaped worm placed on the turning table and having a disk shape and an outer peripheral surface. A slide table for causing the center of curvature of the outer peripheral surface and the axis of the swivel axis to coincide with each other in a plane parallel to the swivel table and passing through the axis of the workpiece bulged in an arc shape equal to A workpiece axis for rotating the workpiece, and an inclination angle of the workpiece axis with respect to the axis of the workpiece by the lead angle of the hourglass worm, and toward the workpiece side along the radial direction of the workpiece A rotating grindstone that forms a tooth groove for forming the hourglass worm on the outer peripheral surface of the workpiece, and the swivel shaft is swung in synchronism with the rotation of the work shaft. Click, said workpiece rotation synchronization with manufacturing apparatus hourglass worm for rolling die that includes a synchronization means for pivoting as turning around the center of curvature.

  (C) Rolling dies for hourglass worms that have a disk shape and the outer peripheral surface bulges in an arc shape equal to the curvature of the root surface of the hourglass worm, and the teeth of the hourglass worm have a disk shape and the outer peripheral surface The workpiece swollen in an arc shape equal to the curvature of the bottom curved surface is rotated, and the workpiece is swung around the center of curvature of the outer peripheral surface of the workpiece in synchronism with the rotation of the workpiece. An hourglass having a tooth groove formed by feeding a rotating grindstone arranged at an angle with respect to the axis of the workpiece toward the workpiece along the radial direction of the workpiece. Rolling dies for worms.

  (D) rotating a workpiece having a disk shape and having an outer peripheral surface bulged in a shape equal to the curvature of the root surface of the hourglass worm, and the curvature of the outer peripheral surface of the workpiece in synchronization with the rotation of the workpiece A rotating grindstone that is swung around the center as a turning center and inclined with respect to the axis of the workpiece by the lead angle of the hourglass worm is sent to the workpiece side along the radial direction of the workpiece. Worm shaft having a hourglass worm manufactured using a rolling die for hourglass worms having a tooth gap.

  (E) A motor with a speed reduction mechanism provided with the worm shaft according to (b).

The conceptual diagram of the manufacturing apparatus of the rolling die for hourglass worms in 1st Embodiment. Sectional drawing of a motor with a speed reduction mechanism. (A) is a front view of a worm shaft, (b) is a cross-sectional view of an hourglass worm. (A) is a perspective view of the rolling die for hourglass worms, (b) is a side view of the rolling die for hourglass worms. Sectional drawing of the manufacturing apparatus of the rolling die for hourglass worms in 1st Embodiment. The block diagram which shows the manufacturing apparatus of 1st Embodiment installed in the general purpose screw grinding machine. The block diagram which shows a general purpose screw grinding machine. (A) is a top view which shows the state of the rotary grindstone which contact | abuts a workpiece | work, (b) is a conceptual diagram which shows the state in which the rotary grindstone is inclined with respect to the workpiece | work by the advance angle of the hourglass worm. (A) is a conceptual diagram which shows a mode that a hourglass worm is manufactured with the rolling die for hourglass worms, (b) is an enlarged view which shows a mode that a hourglass worm is manufactured with the rolling die for hourglass worms. The conceptual diagram of the manufacturing apparatus of the rolling die for hourglass worms in 2nd Embodiment. The conceptual diagram which shows the relationship between the center of curvature of the outer peripheral surface of the workpiece | work in 2nd Embodiment, and a turning center. Sectional drawing of the manufacturing apparatus of the rolling die for hourglass worms in 2nd Embodiment. The block diagram which shows the manufacturing apparatus of 2nd Embodiment installed in the general purpose screw grinding machine. The conceptual diagram for demonstrating the relative position of the workpiece | work in process and a rotating grindstone. The conceptual diagram for demonstrating the positional relationship of the workpiece | work in process and a rotating grindstone. (A) is a graph showing the relationship between the workpiece rotation amount θ and the workpiece turning amount B (θ), and (b) is the workpiece rotation amount θ and the amount x (θ) + Δx (θ) to which the rotating grindstone is fed. (C) is a graph showing the relationship between the rotation amount θ of the workpiece and the amount Δz (θ) by which the workpiece is slid.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1,200 ... Rolling die manufacturing apparatus for hourglass worm, 4 ... Hourglass worm, 5 ... Rolling die for hourglass worm, 5a ... Outer peripheral surface, 5b ... Tooth groove, 31 ... Turning table, 32 ... Slide table , 33 ... Work axis, 34 ... Rotary grindstone, 36 ... General-purpose screw grinder, 37 ... Table, 39 ... Turning axis, 63 ... Work axis drive motor, 70 ... Work, 81 ... Numerical control panel as synchronizing means and control means , 100 ... connecting portion, 201 ... slide mechanism, α ... advance angle, θ ... workpiece rotation amount, x (θ) + Δx (θ) ... amount of feeding the rotating grindstone to the workpiece side, L3 ... workpiece axis, L5 ... turning Axis axis, L4 ... axis of rotating grindstone, L8 ... axis of workpiece axis, L9 ... center line, O2 ... center of curvature of outer peripheral surface of drum worm rolling die, S3 ... spinning table passing through axis of workpiece and Parallel plane, P1 ... The intersection of the axis of the workpiece axis and the axis of the turning axis, P2, P3... Intersection of the axis of the workpiece and the center line passing through the center in the thickness direction of the workpiece.

Claims (12)

Rolling die for hourglass worm having a peripheral surface having a tooth groove for forming a hourglass worm by processing a disk-shaped workpiece and expanding in an arc shape equal to the curvature of the root surface of the hourglass worm A manufacturing method of a rolling die for hourglass worms,
The rotating grindstone that forms the tooth gap is arranged with its axis inclined with respect to the axis of the workpiece by the advance angle of the hourglass worm,
The workpiece is rotated with the center of curvature of the outer peripheral surface as a turning center in synchronization with the rotation of the workpiece, and the rotating grindstone is fed to the workpiece side along the radial direction of the workpiece ,
The axis of the turning axis for turning the workpiece is disposed at a position away from the center of curvature of the outer peripheral surface,
The relative position between the work and the rotating grindstone is the same as the relative position between the work and the rotating grindstone when the work is swiveled with the center of curvature of the outer peripheral surface as the turning center. A method for manufacturing a rolling die for hourglass worms, wherein the position of the workpiece is controlled in accordance with the amount of rotation and the amount of feeding the rotating grindstone to the workpiece side is controlled . In the manufacturing method of the rolling dies for hourglass worms according to claim 1,
A method for producing a rolling dies for hourglass worms , wherein the axis of the swivel axis is disposed so as to pass through an intersection of an axis of the workpiece and a center line passing through a center in the thickness direction of the workpiece . In the manufacturing method of the rolling dies for hourglass worms according to claim 1 or 2 ,
A swivel table mounted on a general-purpose screw grinder and slidably moved by a slide mechanism and swiveled by the swivel shaft;
A work shaft mounted on the turning table and rotating the work;
Synchronization means for rotating the swing axis in synchronization with rotation of the work shaft;
The relative position between the work and the rotating grindstone is the same as the relative position between the work and the rotating grindstone when the work is swiveled with the center of curvature of the outer peripheral surface as the turning center. Control means for controlling the position of the workpiece according to the amount of rotation and for controlling the amount of feeding the rotating grindstone to the workpiece side;
Using a manufacturing apparatus equipped with
A method for manufacturing a rolling die for an hourglass worm , wherein the rotation of the workpiece and the turning of the workpiece are synchronized, and the position of the workpiece is controlled by sliding the table . Rolling die for hourglass worm having a peripheral surface having a tooth groove for forming a hourglass worm by processing a disk-shaped workpiece and expanding in an arc shape equal to the curvature of the root surface of the hourglass worm A manufacturing method of a rolling die for hourglass worms,
The rotating grindstone that forms the tooth gap is arranged with its axis inclined with respect to the axis of the workpiece by the advance angle of the hourglass worm,
The workpiece is rotated with the center of curvature of the outer peripheral surface as a turning center in synchronization with the rotation of the workpiece, and the rotating grindstone is fed to the workpiece side along the radial direction of the workpiece,
A swivel table mounted on a table of a general-purpose screw grinder and swiveled on a swivel axis;
A slide table placed on the swivel table and configured to match the swivel center of the work swung integrally with the swivel table and the axis of the swivel axis;
A work shaft disposed on the slide table for rotating the work;
Synchronization means for synchronizing the rotation of the work shaft and the turning of the turning shaft;
Using a manufacturing apparatus equipped with
A method for manufacturing a rolling die for an hourglass worm, wherein the rotation of the workpiece and the turning of the workpiece are synchronized. In the manufacturing method of the rolling die for hourglass worms according to claim 4 ,
A manufacturing method of a rolling dies for hourglass worms, characterized in that an axis of a turning axis for turning the workpiece and a center of curvature of the outer peripheral surface coincide with each other. The method of manufacturing a hourglass worm for rolling die according to any one of claims 3 to 5,
The rotating table is provided with a work shaft drive motor that is connected to the work shaft and rotates the work shaft . The method of manufacturing a hourglass worm for rolling die according to any one of claims 3 to 5,
A manufacturing method of a rolling dies for hourglass worms, characterized in that a main shaft of the general-purpose screw grinder and the work shaft are connected by a connecting portion . Rolling die for hourglass worm having a peripheral surface having a tooth groove for forming a hourglass worm by processing a disk-shaped workpiece and expanding in an arc shape equal to the curvature of the root surface of the hourglass worm An apparatus for manufacturing a rolling die for hourglass worms,
A swivel table mounted on a table of a general-purpose screw grinder and swiveled on a swivel axis;
A slide table placed on the swivel table, passing through the axis of the workpiece and parallel to the swivel table, for aligning the center of curvature of the outer peripheral surface with the axis of the swivel axis;
A work shaft disposed on the slide table for rotating the work;
In order to form the hourglass worm on the workpiece by being arranged with the axis inclined with respect to the axis of the workpiece by the advance angle of the hourglass worm, and sent to the workpiece along the radial direction of the workpiece A rotating whetstone that forms a tooth gap of
Synchronization means for turning the work in synchronism with the rotation of the work around the center of curvature as the turning center by turning the turning axis in synchronization with the rotation of the work axis;
An apparatus for manufacturing a rolling die for hourglass worms, comprising: Rolling die for hourglass worm having a peripheral surface having a tooth groove for forming a hourglass worm by processing a disk-shaped workpiece and expanding in an arc shape equal to the curvature of the root surface of the hourglass worm An apparatus for manufacturing a rolling die for hourglass worms,
A swivel table mounted on a general-purpose screw grinder and slidably moved by a slide mechanism and swiveled by a swivel axis;
A work shaft mounted on the turning table and rotating the work;
In order to form the hourglass worm on the workpiece by being arranged with the axis inclined with respect to the axis of the workpiece by the advance angle of the hourglass worm, and sent to the workpiece along the radial direction of the workpiece A rotating whetstone that forms a tooth gap of
Synchronization means for rotating the swing axis in synchronization with rotation of the work shaft;
The relative position between the work and the rotating grindstone is the same as the relative position between the work and the rotating grindstone when the work is swiveled with the center of curvature of the outer peripheral surface as the turning center. Control means for controlling the position of the workpiece by sliding the table according to the amount of rotation and controlling the amount of the rotating grindstone fed to the workpiece side;
An apparatus for manufacturing a rolling die for hourglass worms, comprising: In the manufacturing apparatus of the rolling die for hourglass worms according to claim 9,
An apparatus for manufacturing a rolling die for an hourglass worm , wherein the axis of the workpiece axis and the axis of the swivel axis are orthogonal to each other . In the manufacturing apparatus of the rolling die for hourglass worms according to any one of claims 8 to 10,
An apparatus for manufacturing a rolling dies for hourglass worms , wherein the turning table is provided with a work shaft drive motor connected to the work shaft and rotating the work shaft . In the manufacturing apparatus of the hourglass worm for rolling die according to any one of claims 8 to 1 0,
An apparatus for manufacturing a rolling dies for hourglass worms , comprising a connecting portion for connecting a main shaft of the general-purpose screw grinder and the workpiece shaft .

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