WO2004110669A1

WO2004110669A1 - Form rolling method for worm and form rolling die for the method

Info

Publication number: WO2004110669A1
Application number: PCT/JP2004/008115
Authority: WO
Inventors: Shuichi Amano
Original assignee: Nissei Co.,Ltd.
Priority date: 2003-06-11
Filing date: 2004-06-10
Publication date: 2004-12-23
Also published as: JP4077482B2; JPWO2004110669A1

Abstract

A form rolling method for a spiral body for manufacturing the spiral body of a spiral body gear mechanism by from rolling and a form rolling die for the method capable of increasing the form rolled accuracy of the roundness of the form-rolled spiral body. When the form rolling nears the final stage, the outer periphery of a plane die (37) comes into contact with the form rolling pressure regulating cam (29) of a worm form rolling material (25). A contact pressure between the plane die (37) and the form rolling pressure regulating cam (29) becomes weak at a position where a cutout plane (30) is not formed though the pressed amount of the plane die (37) becomes large at the angular position thereof matching the cutout plane (30), whereby the material can be form-rolled in a form near a complete round.

Description

Specification

Spiral rolling method and rolling die

Technical field

The present invention relates to a method for rolling a spiral body for rolling a spiral body and a die for rolling the spiral body. More specifically, for forming a helical gear such as a worm, a helical gear, a helicopter force spline, for fixing, or for forming a spiral body such as a multi-thread screw for converting rotary motion into linear motion by rolling. The present invention relates to a method of rolling a spiral body and a die for the rolling.

Background art

A worm gear mechanism combining a worm and a worm gear mechanism is used for a reduction gear mechanism or the like that can increase a speed ratio. Often used as a mechanism to transmit power from one axis to the other, but not perpendicular to each other.

The present inventors have proposed a worm rolling method and a worm that reduce the number of processing steps while ensuring sufficient gear accuracy (Patent Document 1). Worms rolled by these rolling methods do not present a major problem in terms of accuracy in the case of multi-start worms, but do not have the desired accuracy in the case of high-precision single-start screws (spiral teeth). In particular, there was a problem with the roundness (the degree of deviation of the geometric circular force in the circular section of the worm).

[0004] This out-of-roundness is generated during roll forming, and in the case of a multi-start worm, when rolling a worm rolling material with a rolling die, the rotation of the roll is reduced. This is because the number of meshing teeth differs depending on the angular position. If the number of meshing teeth between the rolling dies and the worm rolling material is different, even if the pressing pressure of the rolling dies is pushed at a fixed pushing amount (feed amount per rotation), the The rolling pressure will differ depending on the rotation angle position on the outer periphery of the material. For this reason, the rolled worm has a different rounding depth at the rotation angle position on the outer periphery, resulting in poor roundness.

Patent Document 1: WO 03/000442 A1

Disclosure of the invention

Problems the invention is trying to solve [0005] The present invention has been made under the above-mentioned technical background, and achieves the following objects.

[0006] An object of the present invention is to provide a method for rolling a spiral body and a die for rolling the spiral body to improve the rolling accuracy of the roundness of the spiral body.

[0007] An object of the present invention is to provide a method for rolling a spiral body and a die for rolling the spiral body to improve the rolling accuracy of the roundness of the spiral body without reducing productivity.

Means for solving the problem

[0008] The present invention employs the following means to achieve the above object.

The method for rolling a helical body according to the first aspect of the present invention is a method for rolling a helical body having a plurality of spiral portions, in which a helical body rolling material is sandwiched between a pair of opposing dies. Manufacturing method,

The material for the spiral body rolling,

A spiral forming part in which the spiral part is formed, and

In order to equalize the pressing pressure of the pair of dies into the spiral rolling material at the rotation angle position of the spiral rolling material during the rolling process, the outer peripheral surface of the spiral rolling material is used. A rolling pressure adjusting cam (29) having different cam surfaces formed in the radial direction is arranged at

A plain die (37) driven integrally with the die is pressed against the rolling pressure adjusting cam (29) to form a roll.

[0009] The method for rolling a helical body according to the second aspect of the present invention is the method for rolling a helical body according to the first aspect of the present invention, wherein the rolling pressure adjusting cam (29) corresponds to the number of threads of the spiral part. It is characterized in that the cam surface is formed and formed.

[0010] A method for rolling a helical body according to a third aspect of the present invention is the method for rolling a helical body according to the first or second aspect of the present invention, wherein the cam surface is a cylindrical surface and a flat surface (30). .

[0011] A method for rolling a helical body according to a fourth aspect of the present invention is the method for rolling a helical body according to the first to third aspects of the present invention, wherein the die is a cylindrical round die.

[0012] The method for rolling a helical body according to the fifth aspect of the present invention is a method for rolling a helical body having a multiplicity of helical portions by forming a helical body rolling material between a pair of opposing dies. A method of rolling rolling, The helical body rolling material has a helical forming part in which the helical part is formed, and a shaft part (50, 52),

At the time of the rolling process, in order to equalize the pressing pressure of the pair of dies into the spiral rolling material at the rotation angle position of the spiral rolling material, the rolling that moves integrally with the die. Arrange the pressure adjusting cam disk (46),

The rolling pressure adjusting cam (46) driven integrally with the die is pressed against the shaft portion (50, 52) to form a roll.

[0013] A method for rolling a helical body according to a sixth aspect of the present invention is the method for rolling a helical body according to the fifth aspect of the present invention, wherein the rolling pressure adjusting cam (46) includes a plurality of spiral threads of the spiral portion. It is characterized in that cam surfaces corresponding to the number are formed and formed.

[0014] A method for rolling a helical body according to a seventh aspect of the present invention is the method for rolling a helical body according to the fifth or sixth aspect of the present invention, wherein the die is a cylindrical round die, and the rolling pressure adjusting cam. Disk

(46) is disk-shaped, and is characterized in that a cam surface (49) is formed on the outer peripheral surface.

[0015] A method for rolling a helical body according to an eighth aspect of the present invention is the method for rolling a helical body according to the fifth or sixth aspect of the present invention, wherein the cam disk (46) for rolling pressure adjustment is attached to the shaft portion (50 Rolling is performed by contacting the cylindrical flange jig (51) inserted into the cylindrical jig (51).

[0016] In the rolling die for rolling force kneading of the present invention 9, in order to roll a spiral having multiple spiral portions, a spiral rolling material is sandwiched between a pair of opposed dies. A rolling die for a rolling force for rolling.

In the rolling process, the rolling is a cam that moves integrally with the die in order to equalize the pressing pressure of the die into the spiral rolling material at the rotation angle position of the spiral rolling material. A pressure adjusting cam (46) is provided.

The rolling die for rolling force kneading of the present invention 10 is a rolling die for caloring the spiral rolling material according to the ninth invention, and the rolling die is a round die. The rolling pressure adjusting cam (46) is disk-shaped, and has a cam surface (49) formed on an outer peripheral surface thereof.

The helical body of the present invention generally includes worms, helical gears, helical splines, multi-threaded screws for fixing or converting rotary motion to linear motion used in a gear mechanism or the like. This means that the thread has a spiral part provided along two or more helical windings.

The invention's effect

[0018] The advantages of the spiral rolling method of the present invention and the rolling dies thereof are as follows. Since the pressing pressure during rolling can be controlled, it is possible to process a spiral having high roundness. became. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the best mode of the present invention will be specifically described with reference to the drawings.

[Embodiment 1]

Hereinafter, Embodiment 1 of the present invention will be described. FIG. 1 is a front view showing an example of a worm shape processed by the worm rolling method of the present invention, and FIG. 2 is an enlarged cross-sectional view taken along line aa of FIG. A screw portion (spiral tooth) 2 is formed at the center of the worm 1. The screw portion 2 of the present embodiment is composed of two threads, that is, a thread 6 and a thread 15. At the center of the screw portion 2, a complete screw portion 3 is formed. At both ends of the complete screw portion 3, incomplete screw portions 4 are formed. The incompletely threaded portion 4 is formed continuously with the completely threaded portion 3. One end of the worm 1 is formed with a male screw 8 for fixing to a driving means such as an electric motor.

The incomplete screw portion 4 gradually rises from the screw bottom 5 which is a substantially cylindrical surface, and has a helical shape continuous with the complete screw portion 3. The incomplete screw portion 4 has a shape as if the outer peripheral portion was cut off. A flange is formed at each end of the screw portion 2, and a shaft portion 7 is formed outside the flange. The shaft portion 7 is a portion for rotatably supporting the worm 1 with a bearing (not shown).

As shown in FIG. 2, one end of the incomplete thread 4 of one thread 6 rises from the rising portion 10 of the screw bottom 5 and continues until the end point 11 of the incomplete thread 4 Is an angle α. At the other end of the thread 6, the incomplete thread 4 starts from the end point 12 of the complete thread 3, and ends at the rising portion 13 of the thread bottom 5. Similarly, the other thread 15 has a similar shape at an angular interval of 180 degrees. In the case of the present embodiment, as shown in FIG. 2, four complete threads 18 appear in a cross section cut in the X-axis direction from the center axis Ο (see FIG. 3 (a)). [0022] As shown in Fig. 2, four complete threads 18 and two incomplete threads 19 appear in the cross section when cut in the Y-axis direction in the plus direction from the central axis 〇 (Fig. 3). (b)). Similarly, four complete threads 18 and two incomplete threads 19 appear on the cross section when cut in the Y direction in the negative direction from the center axis O.

Accordingly, when the worm 1 is cut along a radial plane including the central axis 〇, the cross-sectional areas of the threads 6 and the threads 15 differ depending on the angle. For this reason, when this worm 1 is rolled, the amount of plastic deformation for plastic kneading differs depending on the cross-sectional area depending on the outer peripheral angle. The cross-sectional shape of the screw thread is approximately elliptical, and the three thread threads have a substantially triangular cross-section. For this reason, high roundness processing becomes difficult. The present invention is to provide a correction means for this purpose.

As understood from the above description, the worm in the present invention includes a fixing means and a multi-thread screw for converting rotation into linear motion.

[0024] [Warm rolling material 25]

FIG. 4 shows a worm-rolling material before rolling kamen, FIG. 4 (a) is a front view, and FIG. 4 (b) is a right side view of FIG. 4 (a). The warm rolling material 25 is processed by a processing method such as a cutting process and a rolling process, and is made of an integral material as a whole. In the warm rolling material 25, a cylindrical portion 26 which is a part of the completely threaded portion 3 after the above-described rolling process is formed in a central portion. Tapered portions 27 are formed at both ends of the cylindrical portion 26 so as to be continuous therewith. The tapered portion 27 is a portion that becomes the incomplete screw portion 4 after the rolling process.

[0025] Subsequent to the tapered portion 27, a small diameter portion 28 is formed. The diameter of the small diameter portion 28 is formed slightly smaller than the diameter of the screw bottom 5 described above. That is, the small diameter portion 28 is a portion that is not rolled. A cylindrical rolling pressure adjusting force 29 is formed continuously with the small diameter portion 28. The rolling pressure adjusting cam 29 is a portion that is processed after the rolling process of the thread portion 2 to form the above-described flange, shaft portion 7, and male screw 8 (see FIG. 1).

[0026] The cylindrical rolling pressure adjusting cam 29 is cut away at two locations at an angle of 180 degrees on the outer periphery thereof by cutting or the like, and is cut out in a notched plane 30. The intersection point 31 of the notch plane 30 of the present embodiment (see FIG. 4 (b)) is the angular position intersecting the Y axis of the worm 1 described above. (See Figure 2). That is, this cut surface is a cross section in which four complete threads 18 and two incomplete threads 19 appear (see FIG. 3 (b)). Therefore, at this angle, the rolling pressure is required the most, and this angular position is the position where the wall thickness needs to be removed most. As a result, a uniform rolling pressure over the entire peripheral surface of the worm rolling material 25 can be pressed by a pair of first rolling round dies 40 and second rolling round dies 41 described later. Material.

[0027] [First rolled round die 40]

The worm rolling material 25 is processed by being sandwiched between a pair of first rolling round dies 40 and second rolling round dies 41 for worm processing. FIG. 5 is a front view of one of the first rolled round dies 40. The first rolling round die 40 presses a worm rolled tooth 36 formed on the outer periphery of the cylinder against a workpiece to form a roll. The first rolled round die 40 is arranged so that the rotation axis is parallel to each other, and the second rolled round die 41, which is at an angle of 180 degrees, is placed between the second rolled round die 41 and a foam rolling material 25. Roll. The first rolled round die 40 and the second rolled round die 41 are rotationally driven by a servomotor (not shown) in the same direction in synchronization with each other. Since this rolling device is a known technology (for example, WO 03/000442 A1) and is not the gist of the present invention, its description is omitted.

[0028] In the center of the first rolling round die 40 of the present embodiment, a worm rolling tooth 36 for rolling the screw portion 2 is formed. The shape of the tooth surface of the thread of the worm is a force S of which various shapes are known, and in the case of an involute worm, the tooth profile in the plane perpendicular to the axis is involute. A worm rolled tooth 36 is formed in which the asperities for forming the thread shape by rolling are reversed. At both ends of the worm rolled tooth 36, a disc-shaped plain die 37 is fixed to the body. On the outer periphery of the plane die 37, a cylindrical surface is formed on which rolling teeth, which are irregularities for rolling, are formed.

[0029] The outer periphery of the plain die 37 comes into contact with the above-mentioned rolling pressure adjusting cam 29 of the worm rolling material 25 when the rolling depth reaches the pressing depth at which the rolling force is advanced. Acts as a kind of stopper that regulates At this time, the contact pressure between the plane die 37 and the rolling pressure adjusting cam 29 has a large pushing amount at the angular position of the notch plane 30, and becomes weak where the notch plane 30 is not formed. For this reason, the unit contact length based on the outer circumferential angle position during the rolling process, that is, the contact length between the worm rolling tooth 36 and the cylindrical portion 26 is determined. The pressing force (rolling pressure) per unit length can be made constant. Since the other second rolled round die 41 has the same shape, the description is omitted.

[0030] [Method of rolling of warm rolling material 25]

FIGS. 6 (a) and 6 (c) schematically show the steps of the worm rolling process. At the chucking position of the worm rolling material 25, the work chuck device (not shown) is operated, and the worm rolling material 25 is sandwiched and held between the centers (not shown). While the rotation of the warm rolling material 25 with the first rolled round die 40 and the second rolled round die 41 is stopped, the warm rolled material 25 is moved between the first rolled round die 40 and the second rolled round die 41. To the processing start position. At this time, the foam rolling material 25 is positioned at a predetermined angular position so as to match the angular phase of the imperfect thread portion 4.

[0031] Similarly, the first rolled round die 40 and the second rolled round die 41 are positioned at a predetermined position and a predetermined angle as a processing start point. Next, the first rolled round die 40 and the second rolled round die 41 are activated to rotate in the same rotation direction, and are rotated synchronously with each other. While the first rolled round die 40 and the second rolled round die 41 are rotating synchronously with each other, the pressing hydraulic cylinders (not shown) are driven so that they are pushed closer to each other. This push starts the rolling process (see Fig. 6 (a)).

[0032] At this time, when the lead angle of the worm 1 to be worked is strong and the difference between the finished diameter of the rolling process and the material diameter is large, the lead angle changes during rolling and an error occurs. This error causes a step. When the rolling process is started, even if this step occurs, the worm rolling material 25 moves in the direction of the center axis and self-corrects. Since the worm rolling material 25 can freely slide on a feed plate (not shown), the worm rolling material 25 being rolled is formed by the first rolling round die 40 and the second rolling material. Move (walk) by the value corresponding to the lead angle of the round die 41, the difference between the material diameter and the finished diameter, and the number of rotations (the direction of the arrow in FIG. 6 (b)).

When the rolling process proceeds and the worm rolling material 25 moves by a set amount, this movement is detected by a forward position detection sensor (not shown). When this is detected, the first rolled round die 40 and the second rolled round die 41 stop rotating, and the pushing operation by the hydraulic cylinder is stopped. Further, the first rolled round die 40 and the second rolled round die 41 are retracted in a direction opposite to the pushing direction. In the present embodiment, it retracts by about 0.05-0.2 mm, Release to the extent that the pressing pressure of the structure is removed.

[0034] Thereafter, the first rolled round die 40 and the second rolled round die 41 are pushed again to the rolled position, and reverse rotation is started. Rolling force is started again. As this rolling process proceeds, the outer periphery of the plain die 37 comes into contact with the portion of the rolling pressure adjusting cam 29 of the worm rolling material 25. This contact acts as a kind of stopper that regulates the amount of pushing. For this reason, the push-in amount becomes large in the portion of the notch plane 30, and the push-in amount is limited in the case of the cylindrical portion. As a result, uniform rolling can be performed, so that deformation of an ellipse or the like is small, and a roll can be formed while maintaining a perfect circle.

[0035] Due to the rolls of the first rolled round die 40 and the second rolled round die 41, the warm rolling material 25 is moved in the axial direction opposite to the above-described rolling. It moves and is detected by a backward position detection sensor (not shown). The rotation of the first rolled round die 40 and the second rolled round die 41 is stopped, and the rolling force finishes (see FIG. 6 (c)).

When the rolling process is approaching the final stage, the outer periphery of the plain die 37 comes into contact with the rolling pressure adjusting cam 29 of the worm rolling material 25. At this time, the contact pressure between the plane die 37 and the rolling pressure adjustment cam 29 is large at the angular position of the notch plane 30, and weak at a part where the notch plane 30 is not formed. Near rolling is possible. If necessary, the above-described normal rotation and reverse rotation steps may be repeated. Also, depending on the processing conditions, the insertion accuracy may be improved by inserting a dwell operation that does not perform the pushing operation during the processing.

[Embodiment 2]

In the first embodiment described above, a rolling pressure adjusting cam is formed on the worm rolling material 25. In this correction method, it is necessary to previously process the worm rolling material 25 in units of one piece, and this preliminary processing is disadvantageous in terms of processing cost. FIG. 7 shows a rolled round die 45. FIG. 7 (a) is a front view, and FIG. 7 (b) is a side view of FIG. 7 (a). On the side surface of the body of the rolled round die 45, a flange 47 is provided on the body.

[0038] Rolling pressure adjusting cam disks 46 are fixed to both side surfaces of the flange 47 with bolts 48. A wavy cam surface 49 is formed on the outer periphery of the rolling pressure adjusting cam disk 46. This rolling surface 49 contacts the unprocessed cylindrical portion 50 of the worm rolling material 25. Of the implementation described above In the first embodiment, the force of forming the cam surface on the cylindrical portion 50. In the second embodiment, it is not necessary to form the cam surface. The rolling method is substantially the same as that of the first embodiment.

[Embodiment 3]

FIG. 8 shows a correction method according to the third embodiment in which a plain die is attached, and is a cross-sectional view of a rolled round die. Similar to the second embodiment, the difference is that a ring-shaped flange jig 51 is used for a force worm rolling material 25 which is the same in that a rolling pressure adjusting cam disk 46 is used. The flange jig 51 is inserted into a shaft portion 52 into which a bearing such as a ball bearing of the worm rolling material 25 is inserted. In the present embodiment, two left and right flange jigs are inserted.

[0040] At the time of the rolling process, the flange jig 51 and the shaft portion 52 are fitted so as to be able to rotate relative to each other, but the relative rotation can absorb distortion such as twisting of the material. Further, in the present embodiment, the shaft portion 52 has a finishing force remaining in the present embodiment. However, the shaft portion 52 may be finished as long as the processing distortion or the like can be predicted. Since the diameters of the left and right shaft portions 52 are not always the same, the diameters of the left and right flange jigs 51 are not necessarily the same.

The diameter is determined so that the left and right flange jigs 51 that contact the outer peripheral surface of the rolling pressure adjusting cam disk 46 with an equal pressure. Strictly speaking, the outer diameter of the flange jig 51 is determined to be an optimum value based on the result of actual rolling. According to this rolling method, since the worm is rolled in a state close to a state where the worm is actually used, the processing can be performed with high accuracy in the shape of the tooth profile.

(Other Embodiments)

In Embodiments 1 and 2 described above, a worm having three or four threads may be used instead of a worm having two threads. Those with three threads are generally rolled into a triangular cross section, while four threads tend to be square. The notched planes 30 for this purpose are also provided at three and four equiangular positions. Further, as will be understood from the explanation of the reason described above, the notch plane 30 may be a curved surface instead of a plane. Rather than theoretically determining this curved surface, a curved surface experimentally determined for each workpiece by rolling experiments has better rolling accuracy. Further, instead of the notch plane 30, a method having a shape having the same shape as the notch plane 30 may be fixed to the worm rolling material 25 as a jig. Further, the above-described first rolled round die 40 has the plane dies 37 arranged on both sides thereof, but it is not always necessary to arrange two dies, and one may be sufficient. Similarly, the rolling round die 45 may be arranged on one side of the force, instead of the rolling pressure adjusting cam disk 46 disposed on both sides thereof. In addition, the above-described rolled round die 45 is a cylindrical so-called round die, but it is clear that a plate-shaped flat die may be used instead.

[0044] Worms, multi-threaded screws, helicano resplines, helical gears and the like rolled by the spiral rolling method of the present invention are used as driving parts and fixing parts for electronic devices such as automobiles, home appliances, and hard disks. it can.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a front view showing an example of a worm shape processed by the worm rolling method of the present invention.

FIG. 2 is an enlarged cross-sectional view taken along the line aa of FIG. 1.

[FIG. 3] FIG. 3 (a) is a cross-sectional view taken along the X-axis direction from the center O in FIG. 2, and a cross-sectional view taken along the Y-axis direction from the center 〇 in FIG.

[FIG. 4] FIG. 4 shows a worm-rolling material before rolling, FIG. 4 (a) is a front view, and FIG. 4 (b) is a right side view of FIG. 4 (a). .

FIG. 5 is a front view of a rolled round die with a plain die.

FIG. 6 (a), (b) and (c) are step diagrams showing a rolling step of worm rolling.

[FIG. 7] FIG. 7 shows a rolled round die on which a plain die is mounted. FIG. 7 (a) is a front view, and FIG. 7 (b) is a side view of FIG. 7 (a).

FIG. 8 is a cross-sectional view showing a rolled round die on which a plain die is mounted and a flange provided on a worm rolling material.

Explanation of reference numerals

[0046] 1… Warm

2 Screw part

3… Complete thread ··· Incomplete thread

··· Screw bottom

, 15… Thread

• Shaft

O- ... rising part

I, 12… End point

8- ·-Complete thread

9--Incomplete thread

5- -Warm rolling material 8--Small diameter part

9- --Rolling pressure adjustment cam 6- --Warm rolling 7

1st rolled round die 1 2nd rolled round die

· · · Rolling pressure adjustment cam disk 7 · · · Flange

Claims

The scope of the claims

[1] A method for rolling a spiral body in which a spiral body having a plurality of spiral portions is formed by rolling with a spiral body rolling material interposed between a pair of opposing dies, the spiral body comprising: The material for rolling is

A spiral forming part in which the spiral part is formed, and

A method for rolling a spiral body.

[2] The method for rolling a spiral body according to claim 1,

The cam for adjusting the rolling pressure (29) has a cam surface corresponding to the number of the spiral portions.

A method for rolling a spiral body.

[3] The method for rolling a spiral body according to claim 1 or 2,

The cam surface is cylindrical and flat (30)

A method for rolling a spiral body.

[4] The method for rolling a spiral according to claim 1, wherein the method is selected from claims 1, 2, and 3.

The die is a cylindrical round die

A method for rolling a spiral body.

[5] A method for rolling a spiral body in which a spiral body having a plurality of spiral portions is formed by rolling with a spiral body rolling material interposed between a pair of opposed dies, wherein the spiral body is formed. The material for rolling has a helical forming part in which the helical part is formed, and a shaft part (50, 52),

At the time of the rolling process, a pair of dies are pressed into the spiral rolling material. In order to equalize the force at the rotation angle position of the spiral rolling material, a rolling pressure adjusting cam disk (46) that moves integrally with the die is arranged,

The rolling pressure adjusting cam (46) driven integrally with the die is pressed against the shaft (50, 52) to form a roll.

A method for rolling a spiral body.

[6] The method for rolling a spiral body according to claim 5,

The rolling pressure adjusting cam (46) has a cam surface corresponding to the number of the spiral portions.

A method for rolling a spiral body.

[7] The method for rolling a spiral body according to claim 5 or 6,

The die is a cylindrical round die, and the rolling pressure adjusting cam disk (46) is disk-shaped, and a cam surface (49) is formed on an outer peripheral surface.

A method for rolling a spiral body.

[8] The method for rolling a spiral body according to claim 5 or 6,

The cam disk (46) for rolling pressure adjustment is rolled by contact with a cylindrical flange jig (51) inserted into the shaft portions (50, 52).

A method for rolling a spiral body.

[9] In order to form a spiral having a multi-part spiral portion, a rolling die for rolling is used for rolling with a spiral rolling material between a pair of opposed dies. At the time of the rolling process, a cam that moves integrally with the die in order to equalize the pressing pressure of the die into the spiral body rolling material at the rotational angle position of the spiral body rolling material. A certain rolling pressure adjusting cam (46) is arranged.

A spiral rolling die, characterized in that:

[10] A rolling die for processing the spiral rolling material according to claim 9, wherein the rolling die is a round die, and the rolling pressure adjusting cam (46) is a circle. It is plate-shaped and has a cam surface (49) on the outer peripheral surface

A spiral rolling die, characterized in that: