JPH0352736A - Positioning structure for manufacturing gear having crowning - Google Patents

Abstract

PURPOSE:To efficiently bring a tooth having a crowning of high accuracy to form rolling by allowing both crowning apex corresponding positions of the tooth having a crowning to conform with the center of a form rolling die. CONSTITUTION:By a value which becomes a hole diameter x=2(a1-k) tan(theta/2) of a conical hole of an axial end face of a first columnar gear body 6 side, and a value which becomes a hole diameter x=2(a2-k) tan(theta/2) of a conical hole 8 of an axial end face of a second columnar gear body 7 side, a conical hole is worked on both end faces of an object B to be worked. Subsequently, the object B to be worked, worked in such a way is set between the fixed center and the movable center. Next, when the tip of a reference center part is inserted, the center position of 1/2 (L1/2) of length of its first columnar gear body 6 and the center line of a form rolling die 3 coincide with each other. In such a way, a tooth having a crowning of high accuracy can be formed.

Description

Detailed Description of the Invention [Industrial Field of Application] When manufacturing a gear having crowning at both ends of the shank, the shank is The present invention relates to a positioning structure for manufacturing a gear having a crowning, which allows positions corresponding to both crowning vertices of a tooth having a certain shape to coincide with a cylindrical gear body provided at both ends of the gear body, and enables crowning processing to be performed in an extremely orderly manner.

[Prior Art and its Problems] Conventionally, there have been gears in which teeth with crowning are rolled on the cylindrical gear body at both ends of the shaft. In this case, the tooth widths of the gears often differed.

Therefore, if rolling is performed by setting the center of the longitudinal length of one end of the workpiece p to the center line C of the rolling die and the width of the face, a gear having extremely regular crowning can be manufactured. be able to.

Next, as shown in Fig. 18, when the cylindrical gear main body with the length i in the longitudinal direction on the other end of the workpiece P is set at the reference center part, it will be placed on the center line C of the rolling die. In this case, the positions of the centers (I!./2) of the length l of the workpiece do not match and shift (see Figure 18), which causes the disadvantage that the tooth with the crowning cannot be formed accurately. there were.

That is, if the center line C of the rolling die and the center (ffi/2) of the length l of the workpiece p do not match (see Fig. 18), the tooth thickness of the tooth with crowning is perpendicular to the center line C of the rolling die. It is formed asymmetrically in the direction (tooth width direction), and the maximum bulge position of the crowning amount W is shifted from the center of the tooth width,
This has the disadvantage that the accuracy of the tooth profile of teeth with crowning is reduced, or that tooth contact is inconvenient.

By the way, although the rolling die of a gear rolling machine cannot be moved in the horizontal direction, the reference center section serves as the reference position during processing, so it is It is constructed so that it can be moved in any direction. However, if dimensional positioning is performed by adjusting the reference center part according to each workpiece p, the disadvantage is that in mass production, not only workability and production efficiency are extremely poor, but also accuracy is reduced. was there. To explain these in detail, when positioning the reference center for each workpiece p, it is extremely troublesome to set it to a position that has the same conditions. However, it is extremely difficult to reduce the above error to zero. Also, if you do that,
It takes time, greatly hinders the productivity of mass-produced products, and reduces production efficiency. In addition, it is being developed to install additional equipment to obtain the dimensional position in a short time, but this has the disadvantage of making the gear rolling machine expensive, increasing the product cost, and making the product relatively expensive. .

In addition, in gears with crowning on the cylindrical gear body, a retaining ring groove may be provided at the end of the gear.
In such a case, it is desirable that the center of the longitudinal length of the inner gear part corresponds to the apex of the crowning. Ta.

[Means to solve the problem]

Therefore, as a result of intensive research in order to solve the above problems, the inventor has proposed the invention to a workpiece in which a first cylindrical gear body and a second cylindrical gear body are respectively formed at both ends of the shaft portion. The first cylindrical gear body. From the lengths of the positions corresponding to both crowning vertices and the respective end surfaces of the teeth each having a certain crowning formed on the second cylindrical gear body, the virtual tip position and rolling of the reference center portion having a tip angle of a constant angle are determined. For the difference between the center of the die and the distance from the line,
The value based on the angle of the tip of the reference center portion is the hole diameter of the shaft end surface of the workpiece, and the hole diameter is a conical hole whose top part is at the same angle as the tip angle on the inside of the end surface of the workpiece. In a workpiece that has a positioning structure for gear manufacturing that has a crowning caused by machining, or a workpiece that has a first cylindrical gear body and a second cylindrical gear body formed at both ends of the shaft part, first cylindrical gear body,
The lengths of the second cylindrical gear bodies in the axial direction are different, and from the center position of the length and the length of each end face, the angle of the tip is the virtual tip position of the reference center part having a constant angle. The hole diameter on the shaft end surface of the workpiece is determined by the difference obtained by subtracting the distance from the center line of the rolling die, and the angle of the tip of the reference center part. A positioning structure for manufacturing gears having a crowning formed by machining a conical hole whose top part has the same angle as the tip, or
A first cylindrical gear body of the workpiece, in which a first cylindrical gear body and a second cylindrical gear body are formed at both ends of the shaft portion, respectively;
At least one of the gears having crowning teeth formed on the second cylindrical gear body is located at a position corresponding to the crowning apex at a position different from the longitudinal center of each of the first cylindrical gear body and the second cylindrical gear body. Then, for the difference obtained by subtracting the distance between the virtual tip position of the reference center part whose tip angle is a constant angle and the center line of the rolling die from the length of the crowning apex equivalent position and each end surface, The value based on the angle of the tip of the reference center part is taken as the hole diameter of the shaft end surface of the workpiece, and the hole diameter is determined by machining a conical hole whose top part is at the same angle as the angle of the tip on the inside of the end surface of the workpiece. By creating a positioning structure for manufacturing gears with crowning that can be created by The above-mentioned problem is solved by making it possible to match the positions corresponding to the apexes of both crownings of the teeth having crownings formed on the provided cylindrical gear body, thereby making it possible to carry out the crowning process in an extremely orderly manner.

〔Example〕

Embodiments of the present invention will be described below with reference to FIGS. 1 to 17.

A is a rolling machine for gears, 1 is a fixed center, and the tip of the reference center portion 1a on the tip side is set at an angle θ (about Z6 in the example).
The main body part 1b of the fixed center 1 is, in principle, fixed to the rolling machine main body, and is configured to be finely adjustable in the left and right directions as shown in FIG. ing.

Reference numeral 2 denotes a movable center, which corresponds to the fixed center 1, as shown in FIG. It is pressed and held. The tip of the center shaft portion 2a on the tip side of the movable center 2 is formed at an angle θ (approximately 260 degrees in the embodiment), and the main body portion 2a of the movable center 2
b is configured to be movable in the left and right directions with respect to the rolling machine body, and is configured to be able to fix the workpiece B at its movable center 2 after being pressed.

3.3 is a pair of rolling dies, which are used in the gear rolling machine A.
It is configured to be movable in the vertical direction via guides 4, 4 around one fixed center. The center line n of the rolling die 3 is formed to face in the vertical direction, and the center line n is completely immovable in the horizontal direction. In addition, one of the rolling dies 3.3 is configured to move from below to above (see the right side in Fig. 11) and the other from above to below (see the left side in Fig. 1l) to perform rolling processing. There is.

Furthermore, the structure of the rolling die 3 includes a die root portion that is arc-shaped in the direction perpendicular to the tooth thickness, a die tooth tip portion that is arc-shaped in the direction perpendicular to the tooth thickness, and a tooth trace that is reverse crowned (in this specification, “
It refers to the opposite concept of "crowning". ), and when a cylindrical gear body is rolled by a pair of these, it has an arc-shaped die tooth tip, an arc-shaped die tooth root, and an inverted crowning. Teeth T having crowning are formed by pressing the material with the tooth surface portion of the die.

The workpiece B has a shaft-like structure as a whole, and a first cylindrical gear main body 6 (on the right side in FIG. 1) and a second cylindrical gear main body 7 (first (left side in the figure) are formed respectively. Specifically, a first cylindrical gear main body 6 and a second cylindrical gear main body 7, each having a diameter approximately several mm larger than the diameter of the shaft portion 5, are provided integrally.

Figures 1 to 9. As shown in FIG. 13, the first cylindrical gear main body 6 and the second cylindrical gear main body 7 are located slightly toward the center of the shaft end of the shaft portion 5. That is, this is a case in which the end of the shaft portion 5 slightly protrudes toward the outer end side of the first cylindrical gear body 6 and the second cylindrical gear body 7; It is included in the concept being formed. Further, as shown in FIG. 12, when the first cylindrical gear main body 6 and the second cylindrical gear end body 7 are integrally formed at the outermost end of the shaft portion 5, the shaft portion 5 This is a basic embodiment in which a first cylindrical gear body 6 and a second cylindrical gear body 7 are formed at both ends, respectively.

Here, the first cylindrical gear body 6, the second cylindrical gear body 7
There are multiple embodiments, and the first embodiment has different axial lengths LL2 of the first cylindrical gear body 6 and the second cylindrical gear body 7, as shown in FIG. It is shaped like this.

That is, L1≠L2.

1/2 of each length (Ll/2, L2/2
), that is, the center position, as qI. q2, and the lengths between the center position q+, (lz and the outermost end surface of the shaft portion 5 are a, a
Set it to 2. The center positions ql and q2 are the positions m. , mz. The length a+ and the length a2 are different and serve as parameters, and vary depending on the type, size, etc. of the workpiece B.

Further, in the second embodiment of the first cylindrical gear body 6 and the second cylindrical gear body 7, as shown in FIG. on the other hand(
In FIG. 15, it is the second cylindrical gear body 7, but it may also be the first cylindrical gear body 6. ), the retaining ring groove d is formed near the outer end of the retaining ring groove d. If the length excluding the outside is L, then (L3
/2) is formed as the position m3 corresponding to both crowning vertices of tooth T having crowning. The length between the position m corresponding to the crowning apex and the outermost end surface of the shaft portion 5 is defined as a3.

Further, although the retaining ring groove d is shown in FIGS. 16 and 17, in reality, the tooth T having the crowning is
is machined after manufacturing.

In addition, the above-mentioned first embodiment. In the case of the second embodiment, the shaft portion 5
The outermost end surface of the gear may be the end surface of the first cylindrical gear body 6 or the second cylindrical gear body 7 (see FIGS. 12 and 15).

Further, the fixed center 1 has a tip having a certain angle θ.
Let k be the distance between the virtual tip position y of the tip of the reference center portion 1a and the center line n of the rolling die 3, and this value becomes a constant after adjusting and fixing the fixed center l.

In the above structure, a conical shape 68 is bored in the shaft end face of the workpiece B. In order to process the conical shape 68, it is essential to use a drill 9 having the same angle θ as the angle θ of the tip of the reference center portion 1a.

Therefore, if the hole diameter of the shaft end surface of the conical hole 8 is X, first, the hole diameter X of the conical hole 68 on the shaft end surface on the first cylindrical gear body 6 side is x=2 (at - k) jan (θ/2).

Further, the hole diameter X of the conical hole 8 on the shaft end surface on the second cylindrical gear main body 7 side is x=2 (az −k) tan (θ/2).

Further, when the retaining ring groove d is formed on the first cylindrical gear main body 6 or the second cylindrical gear main body 7 side, the hole diameter X of the conical 68 on the shaft end face is x=2 (a.. k) jan(θ/2).

The above formula has the parameter length aI + a2
+a3 (determined by the axial lengths L+, L2, and L3 of the first cylindrical gear body 6 and second cylindrical gear body 7), k and θ are constants, and X is necessary and sufficient. value is obtained.

As a modification of the conical hole 8, the periphery thereof may be chamfered or formed into an arc shape (see Fig. 3), so the virtual intersection of the end face and the conical hole 8 may be modified. The hole diameter of the hole is sometimes designated as X. In the embodiment, the conical hole 8 has a small-diameter cylindrical hole formed at its tip and a truncated conical hole at its rear end.

[Effect]

First, in a workpiece B provided with a first cylindrical gear body 6 and a second cylindrical gear body 7 each having teeth T having crowning at both ends thereof, the first cylindrical gear body 6, the second cylindrical gear body 7, The columnar gear body 7 is formed with different lengths Ll and L2 in the axial direction, and here,
As mentioned above, the hole diameter of the conical 68 on the shaft end surface on the first cylindrical gear body 6 side is x=2 (a+-k)jan(θ/2)
Also, the hole diameter of the conical hole 8 on the shaft end surface on the second cylindrical gear body 7 side is x=2 (a2-k) jan(θ
/2), a conical hole 8 is machined in the shaft end face of each workpiece B. A large number of workpieces B processed in this manner are then set between the fixed center 1 and the movable center 2 of the gear rolling machine A.

Then, the conical hole 8 in the shaft end face on the first cylindrical gear body 6 side
The hole diameter x = 2 (at - k) jan (θ/2), and when the tip of the reference center portion 1a is inserted into such a conical shape 68, the angle of the tip of the reference center portion 1a also becomes θ. Therefore, the center position ql of 1/2 (L+/2) of the length of the first cylindrical gear main body 6 and the center line n of the rolling die 3 coincide. That is, when forming the teeth T having crowning on the circumferential surface of the first cylindrical gear body 6, the center position of the tooth width is set to the maximum position of the crowning amount W, that is, the crowning apex m. .

Can be done. After machining the teeth, the movable center 2 is moved backward, the workpiece B is removed, and the workpiece B is reversed, and the workpiece B is set between the fixed center 1 and the movable center 2 in the same manner as described above. In the same way as for the first cylindrical gear body 6, teeth T having crowning are manufactured and processed for the second cylindrical gear body 7.

In addition, a tooth T having a crowning forming a retaining ring groove d
In this case, the hole diameter x of the conical hole 8 in the shaft end surface when the retaining ring groove d is formed on the first cylindrical gear main body 6 or second cylindrical gear main body 7 side is x=2 (a. .k) ja
Process as n(θ/2). After doing this, teeth T having crowning are manufactured and processed for the first cylindrical gear body 6 or the second cylindrical gear body 7.

〔Effect of the invention〕

First, in the invention of claim 1, first
Teeth T having crowning formed on the first cylindrical gear body 6 and the second cylindrical gear body 7, respectively, of the workpiece B, which has a cylindrical gear body 6 and a second cylindrical gear body 7, respectively. Crowning apex equivalent position mI, mz + m
3 and the respective end faces a+, az+ az, the reference center portion 1a has a tip angle of a constant angle θ.
For the difference between the virtual tip position y and the center line n of the rolling die 3 by subtracting the distance k, the value based on the angle of the tip of the reference center portion 1a is taken as the hole diameter X of the shaft end surface of the workpiece B. , the hole diameter X is a positioning structure for manufacturing gears having a crowning formed by machining a conical hole 8 whose apex has the same angle θ as the angle θ of the tip on the inner side of the end surface of the workpiece B. As a result, firstly, it is possible to shape the teeth T with highly accurate crowning, and secondly, the rolling operation can be carried out extremely efficiently.

To explain these effects in detail, first, the first cylindrical gear body 6. When the second cylindrical gear body 7 is provided, the conical hole 8.8 is machined under the conditions of the present invention, and the conical shape 68 of the first cylindrical gear body 6 having a length L1 is used as the reference center part. 1a, it is possible to align the center line n of the rolling die 3 with the position m1 corresponding to the crowning apex of the tooth T having a crowning formed on the first cylindrical gear body 6 of the workpiece B. Completed (see Figure 6)
, for a tooth T with a crowning, the crowning apex m. is the center position of the tooth width (see FIG. 14), which has the advantage of being able to manufacture teeth T with extremely regular crowning, and furthermore, the accuracy of the tooth profile of the teeth T with crowning can be made high.

Next, the workpiece B is reversed, and the conical shape 68 of the second cylindrical gear body 7 having a length L2 is set at the reference center portion 1a.
, the crowning apex position m2 of the tooth T having a certain crowning formed on the second cylindrical gear body 7 of the workpiece B coincides with the center line n of the rolling die 3 (Fig. 9). ), for a tooth T with a crowning, the crowning apex m0 is the center position of the tooth width (see Figure 14), and in this case too, the tooth T with a crowning can be machined in an orderly manner, and the tooth profile accuracy is high. It is possible to process crowning.

In addition, a gear with a crowning having a retaining ring groove d (
15 to 17), the position m corresponding to the crowning apex of the first cylindrical gear body 6 or the second cylindrical gear body 7 is aligned with the center line n of the rolling die 3. be able to.

That is, even if the retaining ring groove d has an appropriate length from the outer end surface, the position m3 corresponding to the crowning apex can always be set at the center of the length L3, and even in this case, the tooth with the crowning can be set very accurately. There is an advantage that T can be processed.

As described above, according to the present invention, the first
A cylindrical gear body 6 and a second cylindrical gear body 7 are provided, and the longitudinal lengths of both cylindrical gear bodies are the same or different,
Even if the position corresponding to the crowning apex of the tooth T having the crowning formed therein is at an appropriate position, be sure to set the position corresponding to the crowning apex on each cylindrical gear body with respect to the center line n of the rolling die 3. It has the advantage of being able to be set.

On the other hand, when positioning the reference center part for each workpiece p, it is extremely troublesome to set the position to the same condition, and this is done manually (manual adjustment).
case,! ! ! Even if you are an expert, it is extremely difficult to reduce the above error to zero, and even if you were to do it, it would take time, greatly hindering the productivity of mass-produced products, and reducing production efficiency. let In addition, it is being developed to install additional equipment to obtain the dimensional position in a short time, but this has the disadvantage of making the gear rolling machine expensive, increasing the product cost, and making the product relatively expensive. .

However, in the present invention, the reference center portion 1a is always at a constant position after the reference position is determined as a preliminary step, and the reference center portion 1a is set at a constant position as a function of the difference in length as appropriate. The conical shape 68 of the first cylindrical gear body 6 and the conical shape 68 of the second cylindrical gear body 7 that have been obtained and processed are sequentially reversed and set on the same reference center portion 1a. First cylindrical gear body 6, second cylindrical gear body 7
The positions ml + mz + mz corresponding to the crowning vertices of the tooth T having a crowning shaped respectively can be made to match the center line n of the rolling die 3, and the tooth profile of the tooth T having a crowning as described above can be made to match the center line n of the rolling die 3. Accuracy can be greatly improved, and since no positioning adjustment is required during mass production, the tooth profile can be made highly accurate while workability is extremely good, which in turn can significantly improve production efficiency. This also has the effect of making gears with crowning cheaper.

Next, in the invention of claim 2, first
In the workpiece B in which a cylindrical gear body 6 and a second cylindrical gear body 7 are respectively formed, the axial lengths Ll and L2 of the first cylindrical gear body 6 and the second cylindrical gear body 7 are The center of the length is 1fq+,
For the difference obtained by subtracting the distance k between the virtual tip position y of the reference center portion 1a whose tip has a constant angle θ and the center line n of the rolling die 3 from the length "l+ag" between qz and the end surface, The value based on the angle of the tip of the reference center portion 1a is the hole diameter X of the shaft end surface of the workpiece B, and the hole diameter By adopting a positioning machining structure for gear manufacturing that has a crowning created by machining a conical shape 68 of θ, firstly, it is possible to extremely efficiently roll the tooth T that has a crowning at the center of the face width. Make the most of your efforts.

To explain these effects in detail, according to the present invention, even if the first cylindrical gear body 6 and the second cylindrical gear body 7 having different lengths in the longitudinal direction are provided at both ends of the shaft portion 5, There is an advantage that the longitudinal center position of each cylindrical gear body can be set with respect to the center line n of the rolling die 3, and thereby the first cylindrical gear body 6 and the second cylindrical gear body The longitudinal center of each gear body 7 is the crowning apex m. It is possible to manufacture the tooth T with high precision.

Other structures are similar to the invention of claim 1, and the same effects can be achieved.

Next, in the invention of claim 3, first
A gear with teeth T having crowning formed on a first cylindrical gear body 6 and a second cylindrical gear body 7, respectively, of a workpiece B having a cylindrical gear body 6 and a second cylindrical gear body 7, respectively. at least one of the respective first
The crowning apex equivalent position m3 is at a position different from the longitudinal centers of the cylindrical gear body 6 and the second cylindrical gear body 7, and the angle of the tip is determined from the length al+83 between the crowning apex equivalent position m3 and each end face. The virtual tip position y of the reference center portion 1a having a constant angle θ and the rolling die 3
The value based on the angle of the tip of the reference center portion 1a is defined as the hole diameter X of the shaft end surface of the workpiece B, and the hole diameter By creating a positioning structure for manufacturing gears, which has a crowning formed by machining a conical shape 68 whose apex is at the same angle θ as the angle θ of the tip on the inside of the end face of B, it is possible to create a positioning structure for manufacturing gears. The tooth T having a crowning can be rolled very efficiently so that the position m corresponding to the crowning apex exists at an appropriate position.

These effects are particularly effective when the retaining ring groove d is formed near the end of a gear with teeth T having a crowning formed on at least one cylindrical gear body. In such a case, the crowning apex equivalent position i&m3 is the length from the inner end of the retaining ring groove d to the shaft end surface, and the length L in the longitudinal direction of the cylindrical gear body. Or, the center of the length L3 subtracted from L2 is the gear rolling I! It can be passed through the center line n of the rolling die 3 of A, thereby creating a crowning apex m at the center of the cylindrical gear body excluding the retaining ring groove d. This has the great effect of making it possible to manufacture and process teeth T with crowning that are free from distortion and the like.

Other structures are similar to the invention of claim 1 and can exhibit effects equivalent to this.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is a partially sectional side view of a workpiece used in the present invention;
Figures 2 and 3 are sectional views of essential parts of the workpiece used in the present invention, Figures 4 and 5 are partial cross-sectional schematic plan views showing the processing steps of the present invention, and Figure 6. is an enlarged view of the main part of Figure 5, Figure 7
Fig. 8 is a partial cross-sectional schematic plan view showing the processing steps of the present invention, Fig. 9 is an enlarged view of the main part of Fig. 8, and Fig. 10 is a gear rolling machine used in the present invention. FIG. 12 is a side view of the workpiece used in FIG. 1, and FIG. Fig. 13 is a perspective view of another embodiment of the workpiece, Fig. 14 is a perspective view of a gear having a crowning manufactured according to the present invention, and Fig. 15 is a part showing the processing steps of another embodiment of the present invention. FIG. 16 is a plan view of the tooth with the crowning formed as shown in FIG. 15, FIG. 17 is a perspective view of FIG. FIG. 3 is a plan perspective view of the set of objects. B...Workpiece, 1a...Reference center part, 3...Rolling die, 5...
... Shaft portion, 6... First cylindrical gear body, 7... Second cylindrical gear body, 8... Conical hole, k.
...Distance, n...Center line, y...Virtual tip position, θ...Angle, LI r L2+ L3+ al + a
2+ a3...Length, ql. q2... Center position, X... Hole diameter, m + + m 2 r m
3... Position equivalent to the crowning apex. JP-A-3 52736 (12)

Claims (3)

[Claims] (1) Crowning formed on the first cylindrical gear body and the second cylindrical gear body of the workpiece, in which a first cylindrical gear body and a second cylindrical gear body are respectively formed at both ends of the shaft part. For the difference obtained by subtracting the distance between the virtual tip position of the reference center part whose tip angle has a constant angle and the center line of the rolling die from the length between the positions corresponding to both crowning vertices of the tooth and the respective end faces, The value based on the angle of the tip of the reference center portion is the hole diameter of the shaft end surface of the workpiece, and the hole diameter is a conical hole whose top part is at the same angle as the tip angle on the inside of the end surface of the workpiece. A positioning structure for manufacturing gears that has a crowning feature that can be achieved by machining. (2) In a workpiece in which a first cylindrical gear body and a second cylindrical gear body are respectively formed at both ends of the shaft portion, the axial length of the first cylindrical gear body and the second cylindrical gear body. The distance between the virtual tip position of the reference center part whose tip angle is a constant angle and the center line of the rolling die is subtracted from the length between the center position and each end face. For the difference, the value based on the angle of the tip of the reference center part is taken as the hole diameter of the shaft end surface of the workpiece, and the hole diameter is set so that the top is at the same angle as the angle of the tip on the inside of the end surface of the workpiece. A positioning structure for manufacturing gears that has crowning, which is achieved by machining a conical hole. (3) Crowning formed on the first cylindrical gear body and the second cylindrical gear body of the workpiece, in which a first cylindrical gear body and a second cylindrical gear body are respectively formed at both ends of the shaft part. At least one of the gears having teeth has a position corresponding to a crowning apex at a position different from the center in the longitudinal direction of the first cylindrical gear main body and the second cylindrical gear main body, and the position corresponding to the crowning apex and the respective end faces For the difference obtained by subtracting the distance between the virtual tip position of a reference center part whose tip angle has a constant angle and the center line of the rolling die from the length, calculate the value based on the angle of the tip of the reference center part to be machined. The diameter of the hole on the end surface of the shaft of the object is
1. A positioning structure for manufacturing gears having a crowning, which is formed by machining a conical hole whose apex has the same angle as the tip of the end surface of a workpiece.