JP2002035887A - Sensor ring and manufacturing method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce bearing pressure, increase durability, and reduce cost when manufacturing a sensor ring. SOLUTION: An axially extruding semi-shear working is applied to the side face 1a of a cylindrical stock in the sensor ring 1. Thereby, serrated teeth 2 are formed on the side face 1a of a stock. The cylindrical stock is radially extruded while axially extruding it to apply semi-shear working by making use of a die and a punch having irregularities corresponding to each other in the semi-shear working to form a first tooth 3 formed from the residual part and a second tooth 4 formed from the radially extruded part so as to form a serrated shape. The die and the punch are prevented from getting into contact with the stock as much as possible and sizing may be carried out additionally when necessary.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sensor ring used for detecting an axle rotation speed in, for example, an anti-lock brake system of an automobile, and a method of manufacturing the same.

[0002]

2. Description of the Related Art Sheet metal sensor rings are known which are lightweight, inexpensive and can be easily manufactured by press working. An example is disclosed in Japanese Patent Application Laid-Open No. 7-155,931. In this method, a ring-shaped material is pushed between a die and a punch by forward extrusion to form uneven teeth on the material.

[0003]

However, according to this method, since the molding becomes close to the closed forging, the molding surface pressure increases,
There is a disadvantage that the mold durability (strength, galling, etc.) is poor.
For this reason, a sensor ring formed by machining can be seen, but there is a disadvantage that the cost increases.

Accordingly, an object of the present invention is to provide a sensor ring capable of reducing molding surface pressure, improving mold durability, and reducing cost, and a method of manufacturing the same.

[0005]

A sensor ring according to the present invention is formed by subjecting a side surface of a cylindrical material to a semi-shearing process for extruding in a radial direction, thereby forming uneven teeth on the side surface of the material. .

[0006] It is preferable that the concave and convex teeth include a first tooth formed by a remaining portion alternately arranged in the circumferential direction and a second tooth formed by an extruded portion.

It is preferable that the uneven teeth extend from one end in the axial direction to the middle, and the second teeth are tapered at the middle.

[0008] It is preferable that the back side of the second tooth has a sag shape.

A method for manufacturing a sensor ring according to the present invention comprises:
Using a die and a punch having concavo-convex portions that match each other, the cylindrical material is extruded in the radial direction while being extruded in the axial direction, and semi-shear-processed. The method includes a step of forming the second teeth formed by the portions extruded in the circumferential direction alternately in the uneven shape in the circumferential direction.

The first teeth are left in the recesses of the die, the side faces of the first teeth are formed by the side faces of the projections of the die, and the tip surfaces of the first teeth are recessed in the die. Preferably, the inner surface is non-contact.

In the die provided radially outside the material, the outermost diameter of the concave portion is made larger than the outermost diameter of the first teeth, and the die is provided radially inside the material. Preferably, the innermost diameter of the recess is smaller than the innermost diameter of the first tooth.

Preferably, the second teeth are pushed into the recess of the punch, and a negative clearance is provided on a side surface of the recess so that the second teeth do not contact the inner surface of the recess.

It is preferable that the method further includes a step of sizing the first teeth and the second teeth using another die and a punch.

The entire surface of the first tooth and the second tooth is sized by contacting the other die, and only one of the back surfaces of the first tooth and the second tooth is formed. Is preferably brought into contact with the other punch.

The another punch is formed in an uneven shape, and only the tip end surface of the projection is brought into contact with the back surface of the first tooth, or the another punch is formed in a circumferential shape and the second punch is formed in the second tooth. Preferably, it is brought into contact with the underside of the tooth.

[0016]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

FIGS. 1 and 2 show a rotation detecting sensor ring according to an embodiment of the present invention. This sensor ring 1 is used for detecting the axle rotation speed in an antilock brake system of an automobile. However, the application is not limited to this. The sensor ring 1 is press-fitted and attached to the tip of the hub H attached to the axle. Sensor ring 1
Are provided on the side surface portion 1a from the front end in the axial direction to a predetermined center, and a non-contact sensor (magnetic sensor) S for rotation detection generates a pulse according to the passage of the unevenness, and the axle is based on the pulse. The rotation speed is calculated. The sensor S detects the rotation facing the uneven teeth 2 from a side perpendicular to the sensor ring axis direction. This is a so-called side detection type sensor ring.

The sensor ring 1 is formed integrally by pressing a cylindrical material made of a magnetic material. As the magnetic material, for example, iron, stainless steel, or the like is used, and as the cylindrical material, a general-purpose or dedicated pipe (for example, a steel pipe or the like) is used. The pipe is subjected to a bond treatment as needed.

In this sensor ring 1, the side surface of the pipe as a material is extruded from the outside in the radial direction to the inside at equal intervals in the circumferential direction by semi-shearing processing to be described later to form the uneven teeth 2. Of the uneven teeth 2, the first tooth of the remaining portion is the detection tooth 3, and the second tooth of the pushed-out portion is the relief tooth 4. The detection teeth 3 are located radially outside the relief teeth 4, and the outer diameter of the detection teeth 3 is substantially equal to the outer diameter of the material. The detection teeth 3 and the flank teeth 4 are formed with high precision by sizing processing because the surface portion facing outward in the radial direction is involved in rotation detection, whereas the rear surface portion facing radially inward is irrelevant to rotation detection. Not molded with such high precision. Back face 4 of escape tooth 4
a has a sagging shape. The proximal end of the relief tooth 4 in the axial direction has a tapered shape whose diameter is obviously reduced. The tapered portion is indicated by 5.

A method for manufacturing the sensor ring 1 will be described below. In this manufacturing method, a pipe P as a raw material shown in FIG. 3 is subjected to a half-shearing process by forward extrusion to form uneven teeth, and a processed product formed therefrom is further sized to form a shape of the uneven teeth. It consists of the second step of finishing.

For semi-shearing, a mold shown in FIG. 3 is used. This is mainly composed of an upper die 6 that can be raised and lowered, and a lower die 8 fixed on a bed 7. The lower die 8 includes a lower die 9, an upper die 10, and a constraining die 11, which are sequentially stacked from below on the bed 7, and only the constraining dice 11 can be divided right and left from the center. A processing hole 12 into which the pipe P and the punch 6 can be inserted is provided at the center of these dies 9. An ejection die 13 for taking out a processed product is provided at the bottom of the processing hole 12 so as to be able to move up and down. The pipe P has a simple cylindrical shape, and general-purpose products, commercially available products, and the like can be used.

As shown in FIG. 6, forming concavo-convex portions corresponding to each other are formed on the outer peripheral portion of the punch 6 and the inner peripheral portion of the upper die 10. The concave portion of the punch 6 is indicated by 6a and the convex portion is indicated by 6b, and the concave portion of the upper die 10 is indicated by 10a and the convex portion is indicated by 10b. As shown in FIG. 3, the lower die 9 is also provided with a similar uneven portion 9ab continuous with the uneven portion of the upper die 10, and the uneven portion 9ab provided on the outer periphery of the eject mold 13 is engaged with the uneven portion 9ab. Is done.

As shown in FIG. 4, in the machined hole 12 of the upper die 10, the upper half is simply a circumferential surface, while the lower half is formed with convex portions 10b at equal intervals in the circumferential direction. Have been. The protrusion 10b has a first tapered portion 15 thereon protrudes radially inward with a predetermined taper angle theta _1, fully portion 16 intermediate portion having a constant diameter, the bottom is a predetermined taper angle theta and it has a second tapered portion 17 retracts radially outward a _2. Relatively large predetermined radius R ₁ are attached to the continuation of the complete portion 16 and the first tapered portion 15.

FIG. 5 is a cross-section of a complete unit 16, the outermost diameter D ₁₁ of the recess 10a as shown in this large compared to the outer diameter D _P1 of the pipe P. Note The outermost diameter D ₁₁ is convex portion 1
It is the same as the inner diameter of the machining hole 12 above 0b (see FIG. 4). And out of the recess 10a, the predetermined radius R ₂ is attached to the outer portion than the pipe outer diameter D _P1. Convex part 1
Innermost diameter D ₁₂ = 0b is smaller than the pipe outer diameter D _P1, and larger than the pipe inner diameter D _P2, for example, the distal end surface 20 of the convex portion 10b so as to be located near the middle thickness of the pipe. Thus, it is possible to determine the amount of extrusion when the pipe is extruded radially inward by the projection 10b (in the present embodiment, about half the pipe thickness). In addition, the distal end surface 20 of the convex portion 10b is substantially flat, and small radius R ₃ is attached to corner portions located on both sides of the distal end surface 20.

As shown in FIG. 6, the outermost diameter D ₂₁ of the convex portion 6b of the punch 6 is equivalent to the pipe inner diameter D _P2. Therefore, the pipe P can be fitted to the outside of the punch 6 as it is. on the other hand,
The concave portion 6a of the punch 6 is formed in a water droplet shape as a whole,
Its innermost diameter D ₂₂ is smaller than the innermost diameter of the relief tooth 4 to be pushed out by semi shearing. And both side surfaces 1 of the recess 6a
Negative clearances are provided at 8 and 18 so as not to contact the escape teeth 4. Here, "negative escape" means that the side surfaces 18, 18 are inside the radial direction. Relatively large radius R ₄ are attached to the inner diameter side of the recess 6a. Thereby, the concave portion 6a has a water droplet shape as a whole.

As a result of the concave portion 6a being formed in this manner, the convex portion 6b of the punch 6 has a narrowed base. The distal end surface 19 of the convex portion 6b has a gentle arc shape along the inner diameter surface of the pipe. Smaller radius R ₅ are attached to the corners of the tip end sides of the projecting portion 6b.

As shown in FIG. 3, during semi-shearing, the pipe P is set in the processing hole 12 and
1 is closed, and the pipe P is restrained from the outer peripheral side and centered.
Next, when lowering the punch 6, the punch 6 is inserted into the pipe P, then by the upper face P ₁ of the pipe P to the shoulder portion 21 of the punch 6 is pressed, the upper die pipe P is gradually pushed downward It is pushed into 10. This is a so-called front extrusion mode. When this happens, upper die 1
The portion corresponding to the flank teeth 4 of the pipe P is extruded radially inward by the 0 convex portion 10b and is subjected to semi-shearing, so that the detection teeth 3 and the flank teeth 4 are simultaneously formed. The pipe P is first fitted into the punch 6 and then
Can be lowered.

Referring also to FIG. 6, in the course of the semi-shearing,
The reaction force when pressed by the convex portion 10b is the convex portion 6b of the punch 6.
It is accepted by. Initially, half shearing is performed in the first taper portion 15 of the upper die 10, so that half shearing gradually proceeds. When the material enters the complete portion 16, it becomes the final shape of this step. In the course of the half-shearing, tooth tip face 3a of the detection teeth 3 does not contact the inner surface of the recess 10a of the upper die 10, also escape tooth 4 even concave punches 6 except for the portion corresponding to the base of R ₅ 6a does not touch the inner surface.

[0029] It is a fact that the outermost diameter D ₁₁ of the recess 10a of the upper die 10 and larger than the outer diameter D _P1 of the pipe P,
Smaller than the innermost diameter of the teeth 4 escape the innermost diameter D ₂₂ of the recess 6a of the punch 6, and by providing the negative relief on both sides 18, 18 of the recess 6a. Due to the provision of the negative clearance, both side surfaces 18, 18 of the concave portion 6a do not become frictional surfaces of the material. With this mold configuration, the friction surface between the mold and the material is reduced, and the molding load is reduced. In the convex portion 10b of the upper die 10, the seizure of the mold is prevented by the radius R _3, and the material is gradually deformed while being transferred from the first tapered portion 15 to the complete portion 16 by the relatively large radius R _1. it can.

On the surface side facing the outside of the pipe P in the radial direction, that is, on the detection side, both side surfaces 3b, 3b of the detection tooth 3 and the surface 4b of the relief tooth 4 are formed by the convex portion 10b of the upper die 10, and the detection tooth 3 The surface shape of the pipe P is left as it is on the tip surface 3a. Thereby, relatively high shape accuracy can be obtained on the front side. On the other hand, on the back side facing the inside of the pipe P in the radial direction, that is, on the side opposite to the detection side, the back face 3c of the detection teeth 3 is merely formed (constrained) by the tip end face 19 of the projection 6b of the punch 6, and the entire flank teeth 4 are punched. 6 does not come into contact with the inner surface of the concave portion 6a, but has a sag shape as if pressed by the convex portion 10b. Therefore, although the shape accuracy is low on the back side, this side is not a problem because it is a portion which does not affect the rotation detection and the appearance of the product. In this way, only the unnecessary or important parts are molded with high precision, and the remaining parts are intentionally reduced in precision, so that the reduction of surface pressure load and molding load can prevent mold galling and mold wear. In addition, it is possible to improve mold durability and reduce costs.

The pipe P is lowered to the bottom dead center for a predetermined stroke. When the lowering is completed, the constraining die 11 is opened right and left to reduce the contact area between the material and the mold, and then the ejecting mold 13 is raised to remove the processed product from the mold. In this ejection, the contact area is small, so that the ejection load can be reduced and deformation can be prevented.

If the precision of the processed product can be satisfied, it can be used as the final product of the sensor ring 1 as it is. However, in the present embodiment, in order to further increase the accuracy, a sizing process described below is added. In sizing, when a mold is brought into full contact with a semi-sheared product (hereinafter simply referred to as a processed product), the molding surface pressure increases and at the same time the contact area between the die and the processed product increases. Deformation or the like occurs.

Therefore, in this sizing process, another die 23 and a punch 24 as shown in FIGS.
(Sizing dies and sizing punches) to reduce the contact area as much as possible. That is, the workpiece is entirely contacting the surface only the die 23 of P _1, to increase the shape accuracy, the back side is so as not to contact with the punch 24 only required for processing of the surface. In addition,
This sizing process is performed by the die 23 and the punch 24.
May be combined with the above-mentioned mold, and may be performed simultaneously with the semi-shear processing by one press stroke, or may be performed in another step by another mold.

The dies 23 and the punches 24 are also formed in an uneven shape like the above dies and punches. And both examples of FIGS. 7 and 8, the concave-convex portion entirely of the die 23 is sizing process the entire surface in contact with the entire surface of the semi-shearing the workpiece P _1. On the other hand, on the back side, only the back side of the detection teeth 3 in the example of FIG. 7 and only the back side of the flank teeth 4 in the example of FIG. As a result, it is possible to reduce the molding surface pressure and prevent the seizure of the mold.

In the example shown in FIG. 7, only the tip end surface 26 of the convex portion 25 of the punch 24 (including the corner R portions 27 on both sides thereof) comes into contact with the back surface of the detection teeth 3 to perform sizing processing. The concave portion 28 of the punch 24 is larger than the relief tooth 4 as described above, and a negative relief is also provided. FIG.
In the example, the surface of the punch 24 is simply a circumferential surface, and comes into contact only with the tip of the flank 4. In any case, since the punch 24 only has a meaning as a reaction force receiving when the surface is formed, it is preferable that the punch 24 has a minimum contact area.

Comparing the two, the example shown in FIG. 7 is more advantageous in increasing the shape accuracy of the detection teeth 3 because the material surface pressure on the inner surface of the concave portion 29 of the die 23 can be increased. However, in the example of FIG. 8, since the back side portion of the flank tooth 4 which has not been restrained by the semi-shearing process is formed, the surface pressure of the punch surface can be reduced as compared with the example of FIG. Therefore, which method should be adopted may be determined in consideration of these balances.

As described above, the same effect as described above can be obtained in such sizing.

In the sizing process of the present embodiment, the entire surface is machined. However, if the accuracy of the side surfaces 3b, 3b of the detecting teeth 3 and the surface 4b of the flank 4 is sufficiently high in a semi-sheared product. For example, only the distal end surface 3a of the detection tooth 3 and the corners on both sides thereof may be processed.

As shown in FIG. 1, in the sensor ring 1 obtained in the above two steps, the tapered portion 5 formed at the base end of the flank 4 is the first tapered portion 15 of the upper die 10.
(FIG. 4). The outer diameter of the detection teeth 3 is slightly reduced from the pipe outer diameter _DP1 due to the sizing process. A small taper portion 31 corresponding to the taper portion (not shown) of the sizing die 23 is formed at the base end of the detection tooth 3. In the lower side of the sensor ring 1 pipe-shaped material is left intact, therefore the inner diameter of the press-fitting portion also pipe inner diameter D _P2
Is equal to

By the way, various modifications of the sensor ring can be considered. FIG. 9 shows an example in which the diameter of the press-fit portion to the hub H is slightly increased, FIG. 10 shows an example in which the diameter is reduced in reverse, and FIG. 11 shows an inner surface of the press-fit portion which is enlarged by machining or ironing. This is an example of a diameter. FIG. 12 shows an arrangement in which the arrangement of the detection teeth 3 and the relief teeth 4 is reversed with respect to the above embodiment.
That is, the semi-shearing is performed such that the flank teeth 4 are pushed outward with respect to the pipe P. Along with this, the inner and outer diameter sides of the mold structures shown in FIGS. 3 to 8 are also reversed. Dies are radially inside,
The punch is radially outward. It is clear that the same operation and effect as in the above embodiment can be obtained in any of the modifications.

As described above, various other embodiments of the present invention can be considered.

[0042]

The present invention exhibits the following excellent effects.

(1) The molding load can be reduced.

(2) Mold galling and mold wear can be prevented, and mold durability can be improved.

(3) A low-cost and highly accurate sensor ring can be manufactured.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a sensor ring according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a longitudinal sectional view showing a mold for semi-shearing.

FIG. 4 is an enlarged longitudinal sectional view of a main part of an upper die.

FIG. 5 is a sectional view taken along line BB of FIG. 4;

FIG. 6 is a cross-sectional view showing a state of a half shearing process.

FIG. 7 is a cross-sectional view showing a sizing process.

FIG. 8 is a cross-sectional view showing another sizing process.

FIG. 9 is a longitudinal sectional view showing a modified example of the sensor ring.

FIG. 10 is a longitudinal sectional view showing another modified example of the sensor ring.

FIG. 11 is a longitudinal sectional view showing another modified example of the sensor ring.

FIG. 12 is a longitudinal sectional view showing another modified example of the sensor ring.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Sensor ring 1a Side surface part 2 Irregular tooth 3 Detecting tooth 3a Detecting tooth tip surface 3b Detecting tooth side surface 4 Relief tooth 4a Back surface of flank tooth 5 Tapered part 6 Punch 6a Punch concave part 6b Punch convex part 9 Lower die 9ab Concavo-convex part of lower die 10 Upper dice 10a Concave part of upper dice 10b Convex part of upper dice 18 Concave side surface 23 Sizing die 24 Sizing punch 25 Sizing punch convex part 26 Tip surface of convex part of sizing punch D ₁₁ Outer diameter of concave part P pipe

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G01P 3/488 G01P 3/488 Z

Claims (11)

[Claims] 1. A sensor ring characterized in that a semi-shearing process for extruding in a radial direction is performed on a side surface portion of a cylindrical material, thereby forming uneven teeth on the side surface portion of the material. 2. The sensor ring according to claim 1, wherein the concave and convex teeth are composed of first teeth formed by a remaining portion alternately arranged in a circumferential direction and second teeth formed by an extruded portion. 3. The sensor ring according to claim 1, wherein the irregular teeth extend from one end in the axial direction to an intermediate part, and the second teeth are tapered at the intermediate part. 4. The sensor ring according to claim 1, wherein a back side of the second tooth has a sag shape. 5. A semi-shearing process in which a cylindrical material is extruded in an axial direction and extruded in a radial direction while being extruded in an axial direction by using a die and a punch having concavo-convex portions which coincide with each other. A step of forming irregularly shaped teeth alternately in the circumferential direction with the second teeth formed by radially extruded portions. 6. The first tooth is left in a concave portion of the die, a side surface of the first tooth is formed by a convex side surface of the die, and a tip end surface of the first tooth is formed in the die. The method for manufacturing a sensor ring according to claim 5, wherein the inner surface of the recess is not in contact with the inner surface of the recess. 7. The concave portion of the punch, wherein the second tooth is pushed out, a negative clearance is provided on a side surface of the concave portion, and the second tooth does not contact the inner surface of the concave portion. Method for manufacturing sensor rings. 8. The method according to claim 5, further comprising a step of sizing the first teeth and the second teeth using another die and a punch. 9. An entire surface of the first tooth and the second tooth is sized by contacting the another die, and one of the first tooth and the second tooth is formed. 9. The method for manufacturing a sensor ring according to claim 8, wherein only the back surface is brought into contact with said another punch. 10. The another punch is formed in an irregular shape, and only the tip end surface of the projection is brought into contact with the back surface of the first tooth,
The method according to claim 9, wherein the another punch is formed in a circumferential surface and is in contact with a back surface of the second tooth. 11. A die used in the method for manufacturing a sensor ring according to claim 6, wherein the outermost diameter of the recess is set to the outermost diameter of the first tooth. A die having an outer diameter larger than the outer diameter and, when provided on the radially inner side of the material, the innermost diameter of the recess is smaller than the innermost diameter of the first teeth.