JPH0790320B2 - Continuous production method of helical gears and production equipment therefor - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a continuous production method of helical gears and production equipment therefor.

[0002]

2. Description of the Related Art Conventionally, when manufacturing a helical gear, as a general manufacturing method, after cutting a material from a round bar steel, a gear material is manufactured by cutting or hot, warm or cold forging. The gear material is subjected to gear cutting with a hobbing machine, and finishing is performed with a shaving hobbing machine. When higher accuracy is required, polishing is performed after heat treatment. In addition, crowning is performed separately to reduce rotational noise. However, the gear cutting process by the hobbing machine has a problem that it takes a very long time. As a method of solving the above problems, it is very effective if a helical gear can be manufactured by press working. JP 63-2531 A and JP 6
Japanese Laid-Open Patent Publication No. 3-2532 discloses a method for manufacturing a spur gear with high accuracy in one step.

[0003]

However, in the case of the helical gear, the tooth line, which is the line of intersection between the tooth surface and the pitch surface, is the helical line. On the other hand, the direction in which the shearing force is exerted by the conventional punch and female die is only in the vertical direction. Therefore, the above method cannot be used as it is because it does not coincide with the direction of the tooth trace of the helical gear. The present invention has been made to solve the above problems, and by helically moving the female die, it is possible to produce helical gears by press working, thereby reducing the processing time. It is an object of the present invention to provide a continuous production method of helical gears and a production facility therefor capable of being drastically shortened.

[0004]

As a concrete means for solving the above problems, the present invention mainly processes the upper and lower surfaces into desired shapes by an arbitrary processing method as shown in FIG. 1 in advance. A gear material 1 having an outer peripheral disk shape is prepared, and the gear material 1 has a predetermined helix angle so that the gear material 1 can be subjected to cold tooth profile cutting, and the outer periphery is larger than the finished tooth profile by a margin.
In addition, an irregular involute curve with a tooth width smaller than the finished tooth profile on the root side than the standard pitch circle radius and a tooth width larger than the finished tooth profile on the tip side than the standard pitch circle radius is transferred. The female die 2 is formed by forming a die hole having an inlet taper portion 31 at the lower inlet and having a straight portion 32, a reverse taper portion 33 and a relief portion 34 following the inlet taper portion 31. Female dice 2
After the gear material 1 is sandwiched between the counter 13 and the punch 3 from above and below and the female die 2 is raised from the inlet taper portion 31 to the escape portion 34, the female die 2 is continuously inserted.
The tooth die-cutting process is performed on the outer periphery of the gear material 1 by passing the female die 2 by descending from the relief portion 34 to the inlet taper portion 31. Finishing female die 2 with a certain twist angle for sizing and a nearly finished tooth profile
And has a chamfered portion 35 and an inlet taper portion 31 having a very small taper at the lower inlet and the inlet taper portion 31
Then, a straight female 32, a reverse tapered portion 33 having an extremely small taper, and a helical tooth die hole having a relief portion 34 are bored in a finishing female die 2, and the gear blank 1 having a toothed outer periphery is counted. After being pinched by 13 and the punch 3 from above and below, the finishing female die 2 is raised from the inlet taper portion 31 to the relief portion 34 to generate debris, and subsequently, from the relief portion 34 of the finishing female die 2 to the inlet taper portion. Three
A continuous production method for helical gears is provided, which is characterized in that the gear female 1 having a tooth profile on its outer periphery is subjected to sizing by passing through the finishing female die 2 by descending to 1.

Further, according to the present invention, the outer peripheral disk-shaped gear material 1 is formed by processing the upper and lower surfaces into a desired shape by an arbitrary processing method.
Is a production facility for a helical gear that press-forms a helical helical gear by cold-pressing the female die 2 and the punch 3 to produce a shearing force, and the tooth profile of the female die 2 has a predetermined shape. It has a helix angle, the outer circumference is larger than the finished tooth profile by a margin, and the tooth width is smaller than the finished tooth profile by a margin than the standard pitch circle radius, and the tooth width is smaller on the tip side than the standard pitch circle radius. Is a female die 2 formed by transferring an irregular involute curve larger than the finished tooth profile by a surplus amount, and having an inlet taper portion 31 at the lower inlet and the straight portion 3 following the inlet taper portion 31.
2. A die hole having a reverse taper portion 33 and a relief portion 34 is bored, the tooth profile of the punch 3 has the same twist angle as the female die 2, and the die holder 4 for fixing the female die 2 is fixed. A helical spline 5 having the same helix angle as the female die 2 is provided on the outer peripheral wall, and a helical groove 6 having the same helix angle as the helical spline 5 is provided on the inner peripheral wall of the slide guide plate 12 for guiding the die holder 4. When the female die 2 is moved up and down, the helical spline 5 of the die holder 4 slides in the helical groove 6 of the slide guide plate 12 so that the female die 2 spirally moves, so that the female die 2 is moved to the outer circumference. A helical gear production facility is provided, in which a helical gear is formed on the disc-shaped gear material 1.

[0006]

According to the continuous production method and production equipment for helical gears having the above construction, the die holder 4 is moved when the female die 2 is vertically moved.
The helical spline 5 slides in the helical groove 6 of the slide guide plate 12, whereby the female die 2 spirally moves, and the gear material 1 is processed into a helical gear.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a helical gear production facility of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a configuration diagram showing the entire production facility for helical gears. FIG. 2 is an enlarged view showing a spiral motion mechanism portion of the female die 2 which is a main part of the present invention. The female die on the inner periphery of the female die 2 which is a cylindrical upper die is provided with the same helix angle as the helix angle required for the product in order to process the gear material 1 into a helical gear. As shown in FIG. 3, the female die 2 has an inlet taper portion 31, a straight portion 32, an inverse taper portion 33, and a relief portion 34 as shown in FIG. In the first step of the continuous production method, the taper angles of the inlet taper portion 31 and the reverse taper portion 33 are 20 degrees to 150 degrees, and are appropriately selected depending on the thickness of the gear material 1. Then, the female die 2 is set inside the die holder 4, and is firmly fixed by the set screw 11.
The die holder 4 has a cylindrical shape, and the female die 2 is provided on the outer peripheral portion.
Multiple helical splines 5 having the same twist angle as
Is provided. A helical groove 6 having the same helix angle as the helical spline 5 is provided on the inner peripheral wall of the insertion hole 21a of the slide guide plate 12 that guides the die holder 4. A connecting fitting 7a is screwed (not shown) to the upper portion of the die holder 4.

When the female die 2 is raised, the connecting metal fitting 7a
Is provided so that the hook 26 thereof hooks the flange 25d at the lower end of the slide cylinder 14. The pressing body 8a has a disc shape, and has an insertion hole 21b in the center thereof for loosely inserting the counter 13. The counter 13 is the slide cylinder 1.
The gear material 1 is fixed to the punch 3 by inserting the gear material 1 together with the punch 3 through the insertion hole 21c of No. 4 and the insertion hole 21b of the pressing body 8a and the inner hole of the female die 2. The slide cylinder 14 has a cylindrical shape and, like the pressing body 8a, has a through hole 21c in the center for loosely inserting the counter 13, and a flange 25a at the upper part. The spring 15a is arranged between the pressing body 8b and the flange 25b of the counter 13.

In the lower and upper parts of the slide cylinder 14, the vertical movement of the slide cylinder 14 is applied to the pressing body 8.
a, the die holder 4, and the thrust bearings 9a, 9 to enable conversion into a spiral motion of the female die 2.
b is provided. The pressure receiving plate 16 has a counter boss insertion hole 21d and a slide cylinder insertion hole 21e in a central boss 28.
Is provided, the slide cylinder 14 is inserted into the insertion hole 21e, and the counter 13 and the spring 15 are inserted into the insertion hole 21d.
a and the pressing body 8b are inserted. Then, by attaching the connecting fitting 7b to the bottom surface of the boss 28 of the pressure receiving plate 16, the spring 15 after the gear material 1 is punched out.
The slide cylinder 14 and the counter 13 are connected so as to rise when the pressure receiving plate 16 rises due to the restoring force of b. The guide shaft 27, which is vertically fixed to a plurality of positions of the pressure receiving plate 16 and has the springs 15b incorporated therein, is a lubricating metal bearing 10b of the slide guide plate 12.
Are inserted into the respective insertion holes 21f.

A lubricating metal bearing 10a for reducing the sliding resistance between the slide guide plate 12 and the die holder 4 is provided above the helical groove 6 below the slide guide plate 12.
Is provided. Then, the slide guide plate 12 is supported by the side poles 17 provided vertically to the base plate 23. The punch 3, which is the lower die, is provided with the same helix angle as that of the female die 2 in order to process a toothed gear having an external male tooth die. Then, the punch 3 is press-fitted into the punch holder 19 with a taper 36 provided at a substantially middle portion, and is firmly fixed to the punch holder 19 by a fixing pin (not shown). Further, the punch 3 is provided with a lower flange 25C in a quadrangular shape so as to withstand a large rotational force during processing, and the rotation of the punch 3 is prevented by interaction with the square groove 29 provided in the punch holder 19. . The base plate 23 and punch holder 19 must be in a free state at the time of mold matching. Therefore, two to four fixed gears 39 are provided on the base plate 23, a spur gear 40 having the same module as the fixed gear 39 is provided on the outer peripheral portion of the punch holder 19, and each fixed gear 39 is attached to the base plate 23. It is fixed with a bolt 41 via a brake lining plate 43.

The press-fitting portion of the punch 3 of the punch holder 19 is
The outer diameter is made large so that various sizes of the punch 3 to be replaced depending on the shape of the gear can be accommodated. In addition, the taper 3 which is a connecting portion between the blade portion of the punch 3 and the body portion
6 guides the falling scraps to the scrap removing disk 37. Therefore, the scraps travel along the punch taper portion 36 and fall on the scrap removal disk 37. The scrap removal disk 37 is constantly rotated in one direction by a geared motor 38.
Then, the scraps collected on the scrap collecting disk 37 are discharged to the outside by a mini-conveyor (not shown). Further, as shown in FIG. 2, the escape portion 34 inside the female die 2 is
A high-pressure air injection hole 42 is provided in the vicinity to inject high-pressure air in order to prevent scraps and dust from collecting and also to cool the heat inside the mold.

As shown in FIG. 7, the gear blank 1 can be a bossed work having bosses 1a and 1b on the upper surface and the lower surface, respectively. Also, as shown in FIG.
The gear material 1 may be a cap work having a cap 1c. The punch 3 and the counter 13 are provided with concave portions or convex portions that match the planar shape of the gear material 1.

Next, the tooth profile of the female die 2 will be described. The female die 2 is provided asymmetrically with respect to the center of the tooth crest as shown in FIG. This is because when the female die 2 bites into the gear material 1, a rotary motion is exerted, so that the pressures on the left and right of the tooth crests are not the same, but become higher on the rotational direction side and lower on the opposite side. Therefore, if the tooth profile of the female die 2 is made symmetrical with respect to the center of the tooth crest, the tooth crest of the gear material 1 after processing will not be symmetrical. Therefore, as shown in FIG. 11, the left and right involute curves are changed by about 0.005 to 1.5 mm depending on the thickness of the module and the gear material 1.

Further, due to the expansion at the time of punching, which is a characteristic of the press working, the gear material 1 has a smaller expansion area on the tooth bottom side than the radius of the reference pitch circle, so that the expansion coefficient becomes negative and the gear material 1 shrinks. Further, since the area to be removed is larger on the tooth tip side than the radius of the reference pitch circle, the expansion rate is high. Therefore,
The tooth profile of the helical gear of the female die 2 is based on the Japanese Industrial Standard (JI
In order to produce the high-accuracy gear of S), as shown in FIG. 9, the tooth ridges provided on the female die 2 have a tooth width corresponding to the surplus of the tooth width on the tooth bottom side with respect to the standard pitch circle radius. (JI
It is necessary to manufacture a tooth peak having an irregular involute curve that is smaller than the standard pitch circle radius and the tooth width is larger than the finished tooth profile by the amount of extra thickness on the tip side of the standard pitch circle radius. The surplus amount is selected according to the size of the module, the material of the gear material 1, the thickness, and the like. Basically 0.003 to 0.
It is about 2 mm.

Next, the operation of the gear cutting production equipment, which is the first step of the helical gear having the above-described structure, at the time of descending will be described first. First, the center of the pressure receiving plate 16 of the helical gear according to the present embodiment and the center of the press cylinder 24 of the pressing device are substantially aligned with each other so that the force is evenly applied to the pressure receiving plate 16. Next, the center of the gear material 1 is set to the center of the upper surface of the punch 3. And
When the press cylinder 24 of the pressing device descends, it first comes into contact with the upper pressure-receiving surface of the pressing body 8b and pushes down the pressing body 8b. When the pressing body 8b is pushed down, the spring 1
The counter 13 descends via 5a. Then, the pressing body 8b further descends, and the press cylinder 24 and the pressure receiving plate 16 come into contact with each other from the position where the pressure receiving surface of the pressing body 8b and the pressure receiving surface of the pressure receiving plate 16 become flat,
The pressure receiving plate 16 descends. Each guide shaft 27
Slides on the lubricating metal bearing 10b, so that it smoothly descends to the lower side of the slide guide 12. Further, a downward force is applied to the die holder 4 from the boss 28 of the pressure receiving plate 16 via the thrust bearing 9b, the thrust cylinder 14, the thrust bearing 9a, and the pressing body 8a.

FIG. 4 is an explanatory view in which the state in which the gear blank 1 is processed is continuously exaggerated. The die holder 4, which receives a downward force by the pressing body 8a, performs a spiral motion by adding a rotary motion to the vertical motion as the helical spline 5 on the outer peripheral portion slides in the helical groove 6 of the slide guide 12. When the tip of the counter 13 contacts the gear material 1 in FIG. 4 (1), the gear material 1 is pressed by the counter 13 and the punch 3. The force pressing the gear blank 1 of the counter 13 is always applied by the spring 15a, and becomes stronger as the press cylinder 24 descends. Then, as shown in FIG. 4 (2), the helical gear is punched from the time when the gear material 1 and the inlet taper portion 31 of the female die 2 shown in FIG. 3 come into contact with each other.

As the press cylinder 24 descends, each helical spline 5 slides in the helical groove 6, whereby the female die 2 spirally descends along a predetermined helix angle. As a result, an oblique shearing force is applied to the gear material 1 by the female die 2 and the punch 3, and the gear material 1 further includes the straight portion 32 and the reverse taper portion 3 of the female die 2.
4 and (3) after passing through the relief portion 34, the cutting allowance of the gear material 1 is completely punched out, and the female die 2 becomes the bottom dead center and starts to move upward. At this point, the gear blank 1 is stamped from the disc-shaped gear blank 1 in the shape of a helical gear. As shown in FIG. 12, the gear material 1 at this time is tapered so that the diameter of the upper surface portion is larger than that of the lower surface portion due to the influence of passage through the inlet taper portion 31. Since a strong rotational force is applied to the gear material 1 during the above-described processing, the gear material 1 may rotate. Therefore, the spring constant of the spring 15a is increased to increase the force with which the counter 13 presses the gear material 1 or the gear material 1 is provided with a plurality of insertion holes as shown in FIG. Multiple detent pins 3
The rotation of the gear material 1 can be suppressed by a method such as providing 0.

Next, a description will be given of the operation of the helical gear production facility, which is subsequently performed, when the facility is raised. The bottom dead center of the downward movement of the female die 2 can be detected by sensing the position with a limit switch or a photo sensor. Female dice 2
Press cylinder 2 of the press machine when the bottom dead center of
Set the switching circuit so that 4 switches to rising. Then, when the press cylinder 24 rises, the pressing body 8b and the pressure receiving plate 16 rise due to the restoring force of the springs 15a and 15b. As the pressing body 8b rises, the force with which the counter 13 presses the gear material 1 gradually decreases.

When the pressure receiving plate 16 rises, the connecting fitting 7b lifts the flange 25a of the slide cylinder 14 so that the slide cylinder 14 moves up and the flange 25d comes into contact with the hook hook 26 of the connecting fitting 7a to be lifted. As a result, the die holder 4 moves up. At this time, the die holder 4 is rotated by the helical spline 5 on the outer peripheral wall sliding along the helical groove 6, and is spirally moved in the direction opposite to that at the time of descending to ascend.

The female die 2 spirally moves up in association with the movement of the die holder 4, whereby the gear material 1 passes from the escape portion 34 of the female die 2 to the reverse taper portion 33. At this time, as shown in FIG. 12, there is a taper (provided to be about 0.05 to 0.08 when the gear material 1 has a thickness of 10 mm) by passing through the inlet taper portion 31 at the time of descending. Then, by passing through the reverse taper portion 33, the gear material 1 is processed into a taper opposite to that in the case of passing through the inlet taper portion 31, and as shown in FIG. 13, the central portion φD ₁ of the thickness has the largest diameter. Is large, and the diameter φD ₂ of the upper surface portion and the lower surface portion is as small as possible (0.01 to 0.0 in diameter).
About 3 mm). As a result, the crowning process can be performed on the gear material 1 at the same time. The crowning process is a process to make a peak on the contact surface of the gear, and it has the effect of suppressing noise during meshing. The amount of crowning in the first step is larger than a general amount, but the required accuracy is adjusted in the second step.

Then, it passes through the straight portion 32 and the inlet taper portion 31 and is extracted from the female die 2. Then, the spring 15b is completely restored and the pressure receiving plate 1
When 6 returns to the initial position, the pressure receiving plate 16 stops rising, and only the pressing body 8b moves up. Next, spring 15a
Is restored and the pressing body 8b returns to the initial position, the pressing body 8b
Is stopped, the counter 13 is separated from the gear material 1, and the operation at the time of rising in the first step is finished. According to the first step, the gear material 1 has the inlet tapered portion 31 and the straight portion 3
2. By the action of the reverse taper portion 33 and the relief portion 34,
The hardness of the gear material 1 does not increase, and the flash of the gear material 1 that occurs during extraction can be minimized.

Next, the second step of forming the helical gear by the above-described production facility for helical gears will be described. The female tooth profile of the female die 2 used in the second step has the above-mentioned twist angle, and is provided with an inlet taper portion 31, a straight portion 32, an inverse taper portion 33, and a relief portion 34 as shown in FIG. There is. The angle of the inlet tapered portion 31 is 20 degrees to 1
It is about 50 degrees, and an appropriate angle is determined by a separate experiment. The straight portion 32 has a standard size and is provided straight. The reverse taper portion 33 is provided with a taper having an angle of 20 to 150 degrees in the opposite direction to the entrance taper portion 31. And
The inner diameter of the escape portion 34 is expanded by 10 μm to 200 μm from the reference dimension of the straight portion 32, but the taper angle in the second step is made smaller than that in the first step, and the straight 3
The standard size of 2 also increases the accuracy. Further, since the clearance between the female die 2 and the punch 3 is made small, the purpose of preventing the blade portions of the mold from hitting each other,
Fig. 4 (1) to ensure a clean finish without burrs
As shown in FIG. 3, an appropriate amount of chamfering 3 is applied to the entire circumference of the opening corner portion of the entrance taper portion 31 of the female die 2 and the entire circumference of the tip corner portion of the punch 3.
5 is provided. Other operations except the female die 2 are the same as those in the first step.

Two types of female dies 2 are prepared, one for gear removal in the first step and one for sizing in the second step. For gear removal, which is the first step, it does not require much accuracy, but in order to prevent cracking and chipping of the female die 2 during the second step to improve mold holding, the gear material 1 should not harden. Tooth size and taper slope are set with emphasis on. For the sizing process, which is the second step, since it is the final process, some hardening of the gear material 1 does not pose a problem, but emphasis is placed on the accuracy after processing,
It must be installed close to the required JIS standards and required crowning processing. Further, the extraction amount during the sizing process which is the second step is symmetrical with respect to the upper and lower sides of the reference pitch circle radius as shown in FIG.
It is about 005 to 0.1 mm and is selected from the most suitable place depending on the thickness of the gear.

Then, the two types of female dies 2 are set in the production equipment of the helical gears installed in the two general-purpose presses placed at the positions having a predetermined interval.
The gear material 1 is conveyed between the two presses by an automatic feeding device such as a roll feeder or a gripper feeder, or manually fed by an operator. Further, it is also possible to incorporate two helical gear production facilities into a transfer press device in which a feeding device is incorporated to provide an automatic press.

According to the above-described embodiment, the helical gear manufacturing apparatus can be incorporated into a general pressing apparatus, so that no special apparatus is required. Further, the size of the helical gear to be manufactured can be easily changed by replacing the female die 2 and the punch 3. Further, by exchanging the die holder 4 and the slide guide 12, the helix angle of the helical gear to be manufactured can be changed by changing the helix angle of the helical spline 5 and the helical groove 6. In addition, by incorporating it into the press device,
It is also possible to use a dedicated processing device for helical gears. As the thrust bearing 9a, the thrust bearing 9b, and the bearings used for the scrap removal disk 37, steel balls may be inserted in the U groove or the V groove as shown in FIG.

[0026]

As described above, the helical gear manufacturing method of the present invention has the above-mentioned structure, and since the tooth profile of the female die is an irregular tooth profile, the finished tooth profile should be the product closest to the correct standard. By implementing the press working of the helical gears, the machining time of the helical gears can be greatly shortened, which has an excellent effect that it can be manufactured at low cost. Further, in the helical gear production facility of the present invention, since the die holder is swung by the helical spline and the helical groove, it is possible to process the helical gear on the gear material with the female die.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing the overall configuration of the present invention.

FIG. 2 is an enlarged cross-sectional view of a spiral motion mechanism portion according to an embodiment of the present invention.

FIG. 3 is a cross-sectional view showing a taper portion of a female die.

FIG. 4 is an explanatory diagram continuously showing processing of a gear material.

FIG. 5 is a side view in which the rotation preventing pin of the gear material is provided on the counter and the punch.

FIG. 6 is an explanatory view showing grooves and steel balls as substitutes for bearings.

FIG. 7 is an explanatory view showing a case where a gear material with both bosses is processed.

FIG. 8 is an explanatory diagram showing a case where a gear material with a cap is processed.

FIG. 9 is a plan view showing the tooth profile of the female die in the first step.

FIG. 10 is a plan view showing a tooth profile of a female die in a second step.

FIG. 11 is a plan view showing a state in which the tooth profile of the female die is provided asymmetrically depending on the twisting direction of the helical gear.

FIG. 12 is a sectional view showing a gear material tapered by an inlet taper portion.

FIG. 13 is a cross-sectional view showing a gear material that has been subjected to crowning processing.

[Explanation of symbols]

1 ... Gear material, 2 ... Female die (finish female die),
3 ... punch, 4 ... Dice holder, 5 ... Helical spline, 6 ... Helical groove, 12 ... Slide guide plate, 13 ... Counter, 14 ... Slide cylinder, 15a-15b ... Spring, 21a-2
1f ... Insertion hole, 31 ... Inlet taper part, 32 ... Straight part, 33 ... Reverse taper part, 34 ... Relief part

 ─────────────────────────────────────────────────── ─── Continuation of front page (56) Reference JP-A-2-63633 (JP, A) JP-A 61-195724 P, A) JP-A 63-2531 (JP, A) JP-A 63-2532 ( JP, A) JP 63-10037 (JP, A) JP 57-134230 (JP, A) Actually open 61-12554 (JP, U)

Claims (2)

[Claims] 1. A gear material in the form of an outer peripheral disk, the upper and lower surfaces of which are machined into a desired shape by an arbitrary machining method, is prepared in advance, and a predetermined helix angle is formed so that the gear material can be subjected to cold tooth profile cutting. The outer circumference is larger than the finished tooth profile by the extra thickness, and the tooth width is smaller than the finished tooth profile by the extra thickness than the standard pitch circle radius, and the tooth width is finished on the tooth tip side than the standard pitch circle radius. A female die that is formed by transferring an irregular involute curve that is larger than the tooth profile by the extra thickness,
A female die having an inlet taper portion at the lower inlet and a die hole having a straight portion, a reverse taper portion and a relief portion following the inlet taper portion, the gear material is counter-punched and punched from above and below. After raising the female die from the inlet taper portion to the relief portion by sandwiching it, then by lowering it from the relief portion of the female die to the inlet taper portion, the female die is passed through and the tooth profile is cut on the outer periphery of the gear material. Further, a finishing female die having a predetermined helix angle and having a substantially finished tooth profile is formed so that the gear material whose outer periphery has a tooth profile is subjected to cold sizing processing. Section and a very small taper inlet taper section, followed by a straight section, and a helical tooth die hole having a very small taper reverse taper section and a relief section. After punching the finishing female die, sandwich the gear material whose outer circumference is tooth-shaped from above and below with a counter and a punch, raise the finishing female die from the inlet taper portion to the escape portion, and then generate debris. Then, the finishing female die is passed through the finishing female die to move from the relief portion of the finishing female die to the inlet taper portion to perform sizing processing on the gear material having the tooth profile of the outer circumference. Continuous production method. 2. A cold-gear helical gear by punching a peripheral disk-shaped gear material, the upper and lower surfaces of which are processed into a desired shape by an arbitrary processing method, by causing a shearing force to be generated by a female die and a punch. Is a production facility of a helical gear to press-mold, the tooth profile of the female die has a predetermined helix angle, the outer circumference is larger than the finished tooth profile by a margin, and the root side of the reference pitch circle radius. A female die with a tooth width that is smaller than the finished tooth profile by an extra amount, and on the tip side of the reference pitch circle radius that is larger than the finished tooth profile by an extra amount, which is an irregular involute curve. The entrance has a taper part and the entrance taper part is followed by a straight part,
A die hole having a reverse taper portion and a relief portion is bored, the tooth profile of the punch has the same helix angle as the female die, and the same as the female die on the outer peripheral wall of the die holder for fixing the female die. A helical spline having a helix angle of, and a helical groove having the same helix angle as the helical spline is provided on the inner peripheral wall of the slide guide plate that guides the die holder, and the helical spline of the die holder when the female die moves up and down. However, by helically moving the female die by sliding in the helical groove of the slide guide plate, the female die forms a helical gear on the outer peripheral disc-shaped gear material. Gear production equipment.