JP2007333025A - Manufacturing method of rolling/sliding component - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method which can shorten a dimension L<SB>21</SB>of chamfering portion 21a while preventing or suppressing a formation of projection made from nitride in a boundary portion between a rolling/sliding surface 19 and the chamfering portion 21a following soft nitriding treatment. <P>SOLUTION: In a condition before performing soft nitriding treatment for forming soft nitriding treatment layer, the above-mentioned chamfering portion 21a is constituted by an outside slant plane 17 sharp in a slant angle α and an inside slant plane 18 dull in a slant angle β. Additionally, the above-mentioned soft nitriding treatment layer is formed in the above-mentioned chamfering portion 21a consisting of these outside and inside slant plane portions 17, 18, and the above-mentioned rolling/sliding surface 19. Therefore, counter surface can be prevented from wearing caused by this projection by preventing or suppressing the formation of the above-mentioned projection in such a way that the boundary portion between the rolling/sliding surface 19 and the chamfering portion 21a is formed near 180 degrees in angle. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a roller sliding component that is in rolling contact or sliding contact with a mating surface, such as a roller for a cam follower constituting a valve mechanism of an engine, a roller (including a needle bearing) constituting a roller bearing (including a needle bearing), or the like. The present invention relates to an improvement of a manufacturing method. Specifically, to improve wear resistance, based on soft nitriding treatment applied to the rolling sliding surface that is in rolling contact or sliding contact with the mating surface, the end of this rolling sliding surface is prevented from rising, An object of the present invention is to realize a manufacturing method capable of obtaining a rolling and sliding component capable of preventing the occurrence of significant wear on the mating surface.

For the purpose of reducing the friction inside the engine and reducing the fuel consumption rate, the cam follower provided on the rocker arm that converts the rotation of the camshaft synchronized with the crankshaft to the reciprocating motion of the intake valve and exhaust valve is provided with a roller. It has been conventionally known that the roller and the outer peripheral surface of the roller are brought into rolling contact with the outer peripheral surface of the cam as described in, for example, Patent Documents 1 to 4 and the like. In order to rotatably support the roller on the cam follower, a pivot shaft is installed on the cam follower in parallel with the cam shaft, and the roller is rotatably supported around the pivot shaft. As the structure for rotatably supporting the roller around the pivot shaft, the following three structures shown in (A) to (C) are known.
(A) A structure in which the roller is rotatably supported directly around the pivot (sliding contact between the outer peripheral surface of the pivot and the inner peripheral surface of the roller).
(B) A structure in which a radial needle bearing is provided between the outer peripheral surface of the pivot and the inner peripheral surface of the roller.
(C) An inner diameter roller is provided between the outer peripheral surface of the pivot and the inner peripheral surface of the roller. The inner roller is rotated with respect to the pivot, and the roller (outer roller) is rotated with respect to the inner roller. ) Rotating, double roller type structure.

  There are advantages and disadvantages to these three types of structures, but the (C) double roller type structure ensures quietness, low torque, compatibility with high engine output, durability, and low cost. In recent years, the number of use cases has been increasing in view of making the conversion parallel to each other at a relatively high level. FIG. 3 shows a double roller type cam follower device for a valve operating mechanism of an engine described in Patent Documents 3 and 4 and the like, which has been conventionally known.

  In the case of this conventional structure, the camshaft 1 is fixed to the camshaft 1 that rotates in synchronization with the crankshaft of the engine, and opposes the cam 2 that rotates together with the camshaft 1. A rocker arm 3 for reciprocating the valve or the exhaust valve is provided. Further, a support shaft 5 made of an iron alloy is spanned between a pair of support wall portions 4, 4 provided at a part (end portion or intermediate portion) of the rocker arm 3 at intervals. Yes. Around the support shaft 5, a cylindrical inner diameter side roller 6 and an outer diameter side roller 7 each made of an iron-based alloy are rotatably supported, and the outer peripheral surface of the outer diameter side roller 7 of these is supported. Is in rolling contact with the outer peripheral surface of the cam 2.

  When the cam 2 rotates together with the camshaft 1 during the operation of the engine, the outer diameter side roller 7 is displaced in response to a change in the outer diameter of the cam 2, and the rocker arm 3 is oscillated and displaced. The intake valve or exhaust valve is reciprocated. At this time, the outer peripheral surface of the outer diameter side roller 7 and the outer peripheral surface of the cam 2 are in contact with each other in a state almost close to pure rolling. The outer diameter side roller 7 rotates at a rotational speed at which the peripheral speed of the outer peripheral surface substantially coincides with the peripheral speed of the outer peripheral surface of the cam 2. On the other hand, the inner diameter side roller 6 rotates at about half the rotational speed of the outer diameter side roller 7. The contact portion between the outer peripheral surface of the inner diameter side roller 6 and the inner peripheral surface of the outer diameter side roller 7 and the contact portion between the inner peripheral surface of the inner diameter side roller 6 and the outer peripheral surface of the support shaft 5 are all in sliding contact. However, the sliding speed can be kept low compared to the structure (A). With these actions, according to the structure shown in FIG. 3, the frictional force acting between the rocker arm 3 and the cam 2 can be reduced, and the fuel consumption rate can be reduced during engine operation.

In order to further improve the torque reduction and durability of the cam follower device for an engine valve operating mechanism constructed and operated as described above, at least the inner diameter of the inner diameter side roller 6 and the outer diameter side roller 7 is selected. The formation of a lubricating coating on both the inner and outer peripheral surfaces of the side roller 6 is also described in Patent Document 4 and is conventionally known. FIG. 4 shows a structure in which a lubricating coating 10 is formed on both inner and outer peripheral surfaces of the inner diameter side roller 6, and FIG. 5 shows a lubricating coating 10 on both inner and outer peripheral surfaces of the inner diameter side and outer diameter side rollers 6 and 7. The structure in which 10a is formed is shown. The above-mentioned Patent Document 4 describes various types of such lubricating coatings 10 and 10a. Of these, the soft nitriding treatment layer can be formed at a relatively low cost and has excellent durability. It is preferable because of its low aggression on the mating surface (abrasion of the mating surface can be suppressed). That is, (gas) soft nitriding treatment is performed on a surface of a low-grade steel such as SPC, carbon steel, cast iron, STKM, etc. for a relatively short time (90 to 150 min), thin (about 8 to 15 μm), and relatively hard. Low (Hv of about 400 to 700), Fe ₃ N · Fe ₄ N compound layer soft nitrided layer of Fe and N). For this reason, unlike the gas nitriding treatment (not soft nitriding treatment), the above three effects can be obtained. 4 to 5 exaggerate the size of the radial gap between the members.

  However, the durability of the mating surface cannot always be sufficiently ensured even if soft nitriding is performed on the inner and outer peripheral surfaces of both the inner and outer rollers 6 and 7 as shown in FIGS. However, it became clear by research of the present inventors. Specifically, a soft nitride layer is formed on the surface of a cylindrical material (base material) 8 made of an iron-based alloy (lower steel as described above) having a shape shown by a chain line in FIG. When, for example, the inner diameter side roller 6 is processed as shown by a solid line in FIG. 6, a nitride compound protrusion 9 is formed at the axial end of the peripheral surface (inner peripheral surface and outer peripheral surface) of the inner diameter side roller 6. Is generated in a state protruding in the radial direction. FIG. 7 shows a state immediately after soft nitriding is performed on a cylindrical material and a soft nitriding layer is formed on the surface (both inner and outer peripheral surfaces and both axial end surfaces) of the material to form an inner diameter side roller 6. The shapes of the inner and outer peripheral surfaces of the inner diameter side roller 6 are shown. 7A shows the bus bar shape of the outer peripheral surface, and FIG. 7B shows the bus bar shape of the inner peripheral surface. FIG. 7 shows the horizontal direction (axial direction of the inner diameter side roller) at 10 times the actual dimension, and the vertical direction (radial direction of the inner diameter side roller) at 1000 times the actual dimension. . From FIG. 7 as described above, it can be seen that, along with the soft nitriding treatment, ridges protruding in the radial direction are formed at both axial ends of the inner and outer peripheral surfaces.

  The surface hardness of the nitrocarburized layer is lower than that of a nitrided layer (surface hardness: Hv 700 to 1200), but is higher than the surface hardness of a general iron-based alloy. Moreover, since the said protrusion 9 is very narrow, the surface pressure of the contact part of the front-end edge of this protrusion 9 and the other party's surface becomes very high. As a result, when the inner diameter side roller having the protrusion 9 is incorporated in the cam follower device for the valve mechanism of the engine as shown in FIGS. 3 to 5 described above, the inner peripheral surface of the outer diameter side roller 7 which is the mating surface, A part of the outer peripheral surface of the support shaft 5 is worn significantly. FIG. 8 shows a state of remarkable wear that occurs on the inner peripheral surface of the outer diameter side roller 7 and a part of the outer peripheral surface of the support shaft 5 due to such a cause. 8A shows the inner peripheral surface of the outer diameter side roller 7 in a state after operation for a predetermined time, FIG. 8B shows the outer peripheral surface of the inner diameter side roller 6, and FIG. 8C shows the inner peripheral surface. (D) shows the bus bar shape of the outer peripheral surface of the support shaft 5. The vertical and horizontal magnifications are the same as in FIG. From FIG. 8 as described above, it can be seen that the generation of the protrusion 9 adversely affects the durability of the mating surface.

Although the cause of the generation of the protrusion 9 that causes such deterioration in durability has not been completely elucidated, the present inventor has generated a nitrocarburized layer on both ends of the circumferential surface in the axial direction. However, it was thought that it was because it progressed from both sides in the axial direction. In other words, the soft nitriding layer is formed by C and N supplied from the gas (carburizing gas + NH ₃ ) in the processing vessel entering the material (base material) of the inner diameter side roller 6 to generate a compound ( In particular by nitridation by N penetration). If the supply of N is uniformly performed on the entire surface of the material, the protrusion 9 is not formed. However, in the case of the inner diameter side roller 6, There is a chamfer 21 as shown in FIG. When soft nitriding is performed, the N is not only from the outer peripheral surface of the inner diameter side roller 6 but also from the chamfered portion 21 and both end surfaces in the axial direction, as indicated by arrows in FIG. Infiltrate. In the conventional case, the inclination angle θ of the chamfered portion 21 with respect to the central axis of the inner diameter side roller 6 is relatively large, about 30 degrees. Therefore, N that has entered from the cylindrical surface portion 11 and N that has entered from the chamfered portion 21 gather at the boundary between the axial end of the cylindrical surface portion 11 and the chamfered portion 21 in the outer peripheral surface. It was considered that the amount of the compound at the boundary portion increased (nitridation at the boundary portion proceeded more than the other portions) to form the protrusion 9.

Based on such an idea (hypothesis), the present inventor can suppress the concentration of N at the boundary portion between the chamfered portion and the cylindrical surface portion by reducing the inclination angle of the chamfered portion, thereby generating the protrusion 9. Therefore, an invention was made to suppress the inclination angle of the chamfered portion to 3 to 15 degrees (Japanese Patent Application No. 2005-192166). FIG. 10 shows a roller 12 for a cam follower device for an engine valve mechanism according to the present invention. In the case of the roller 12 according to the present invention, the inclination angles θ _i and θ _o with respect to the central axis of the roller 12 are relatively moderate at 3 to 15 degrees, respectively, at both axial ends of the inner and outer peripheral surfaces. The inner diameter side and outer diameter side double-sided chamfers 13 and 14 are formed. In this way, when the inclination angles θ _i and θ _o of the inner diameter side and outer diameter side double-sided chamfers 13 and 14 formed at both axial ends of the inner and outer peripheral surfaces are moderated, the double-sided chamfers 13 and 14 are formed. And the angle at the boundary between the inner and outer cylindrical surfaces 15 and 16 (complementary angles of the inclination angles θ _i and θ _o ), which are present at the axially intermediate portions of the inner and outer peripheral surfaces, are 180 degrees. Close to. As a result, the concentration of N at each boundary portion associated with the soft nitriding treatment is alleviated, and the generation of the protrusions 9 as shown in FIGS. 6 and 7 is eliminated or alleviated.

However, in the case of the above-described invention, the inclination angles θ _i and θ _o of the inner diameter side and outer diameter side double-sided chamfers 13 and 14 are constant over the entire length of the double-sided chamfered parts 13 and 14. On the other hand, the difference (diameter difference of the chamfered portion) between the diameters of the double-sided chamfered portions 13 and 14 on the axial end surface side of the roller 12 and the diameters of the cylindrical surface portions 15 and 16 on both the inner and outer diameter sides is as follows. It is necessary to secure a certain amount. The reason for this is to facilitate the fitting operation between the roller 12 and the mating member, and to facilitate the feeding of lubricating oil between the circumferential surface of the roller and the circumferential surface of the mating member. It is. For this reason, when the inclination angles θ _i and θ _o of the double-sided chamfers 13 and 14 are made constant over the entire length as in the previous invention, it is necessary to secure a difference in diameter between the chamfered parts. The axial lengths L _i and L _o of the portions 13 and 14 must be increased to some extent. In the case of the prior invention, the lengths L _i and L _o in the axial direction of the double-sided chamfers 13 and 14 are about 0.8 to 1.5 mm, respectively.

In such reason, the inner diameter side, the axial length L _i of the outer diameter side duplex-up sections 13 and 14, a larger L _o, the contact or sliding rolling contact with the mating surface during operation, the inner diameter side, the outer The widths W _i and W _{o of the} radial side cylindrical surface portions 15 and 16 become narrower. For example, the roller 12, indicating an internal diameter side roller 6 or the outer diameter side roller 7 for cam follower device valve mechanism of the engine (see FIG. 3-5), the total width W _T of the roller 12 is at most from 10mm It is about 15mm. For example, the total width W _T and 12 mm, the axial length L _i of the double-sided chamfer 13, when the L _o and 1.2 mm, since these double-sided chamfer 13, 14 present on both sides axis direction The widths W _i and W _o of the cylindrical surface portions 15 and 16 are 12 mm−2 × 1.2 mm = 9.6 mm, respectively.

The roller is often pressed against a large force to the mating surface when in use, a portion in contact with the mating surface, the width W _i of both cylindrical surface portion 15 and 16, that W _o is narrowed, the This leads to an increase in the contact surface pressure of the part. This increase in contact surface pressure is disadvantageous in terms of ensuring the durability of the roller and the mating member. On the other hand, assuming that the widths W _i and W _o of the cylindrical surface portions 15 and 16 are the same, the axial lengths L _i and L _{o of the} double-sided chamfers 13 and 14 are increased. This leads to an increase in the total width W _T of 12, and an increase in the size and weight of the roller 12. For example the inner diameter side roller 6 or the outer diameter side roller 7 for cam follower device valve train engine, the need to install in a limited space, full width W _T of the roller 12 is preferably even slightly smaller. Further, since both the inner diameter side and outer diameter side rollers 6 and 7 reciprocate at high speed during operation of the engine, it is necessary to reduce the inertial mass as much as possible in order to improve the performance of the engine.
Considering these things, the axial length L _i of the double-sided chamfer 13, 14, L _o is increase it is not preferable.

JP 59-183007 A JP-A-8-74526 Japanese Patent Laid-Open No. 11-247845 JP 2004-257287 A JP 2002-97563 A

  In view of the circumstances as described above, the present invention realizes a method for manufacturing a rolling and sliding component capable of reducing the size of a chamfered portion while preventing or suppressing the generation of protrusions due to soft nitriding. To do.

  The rolling sliding part which is the object of the manufacturing method of the present invention is made of an iron-based alloy, and has a rolling sliding surface 19 which is in rolling contact or sliding contact with a mating member as shown in FIG. Then, a chamfered portion 21 a is provided at the end edge portion of the rolling sliding surface 19, which is inclined in a direction of being recessed from the center portion of the rolling sliding surface 19 toward the end edge. Further, a soft nitriding layer 20 (surface layer portion in a completed state shown by a solid line in FIG. 1) is formed on the surface portions of the chamfered portion 21a and the rolling sliding surface 19.

In the production method of the present invention for producing such a rolling sliding part, as shown by a chain line in FIG. 1, in the state before performing the soft nitriding treatment for forming the soft nitriding treatment layer 20, The chamfered portion 21 a is composed of an outer inclined surface portion 17 and an inner inclined surface portion 18.
Of these, the outer inclined surface portion 17 is located on the edge side (left side in FIG. 1), and the inclination angle α with respect to the central portion of the rolling sliding surface 19 is relatively steep.
On the other hand, the inner inclined surface portion 18 is located closer to the center of the rolling sliding surface 19 (right side in FIG. 1), and the inclination angle β with respect to the central portion of the rolling sliding surface 19 is gentle.
Then, the nitrocarburized layer is applied to the chamfered portion 21a and the rolling sliding surface 19 (in fact, the entire surface of the rolling sliding component) composed of the outer inclined surface portion 17 and the inner inclined surface portion 18 as described above. Soft nitriding treatment is performed to form the film.
By this soft nitriding treatment, N is infiltrated into the material (base material) for producing the rolling sliding part, and the chamfered portion 21a composed of the outer and inner inclined surface portions 17 and 18 and the rolling sliding surface 19 are formed. In addition, the soft nitriding layer 20 is formed on the surface of the material.
In the state after the soft nitriding layer 20 is formed, both the outer and inner inclined surface portions 17 and 18 may remain (the inclination angle may change in the middle of the chamfered portion), but remain. (Even if the angle of inclination of the chamfered portion is constant over the entire width).

When carrying out the manufacturing method of the rolling sliding part of the present invention as described above, for example, as described in claim 2, the rolling sliding surface 19 is a cylindrical outer peripheral surface, and the chamfered portion is an end. The outer diameter is inclined in the direction of decreasing toward the edge. And the inclination | tilt angle (beta) of the said inner side inclined surface 17 with respect to the central axis of this outer peripheral surface is set to the range of 3-15 degrees (preferably 4-7 degrees).
Alternatively, as described in claim 3, the rolling sliding surface 19 is a cylindrical inner peripheral surface, and the chamfered portion is inclined in a direction in which the outer diameter increases toward the end edge. And the inclination | tilt angle (beta) of the said inner side inclined surface 17 with respect to the central axis of this outer peripheral surface is set to the range of 3-15 degrees (preferably 4-7 degrees).

According to the manufacturing method of the rolling sliding part of the present invention as described above, it is possible to prevent or suppress the generation of protrusions at the boundary portion between the chamfered portion 21a and the rolling sliding surface 19 due to the soft nitriding treatment. while, can be shortened axial dimension L ₂₁ of the chamfered portion 21a.
Of these, the formation of protrusions is prevented by making the inclination angle β of the inner inclined surface portion 18 adjacent to the rolling sliding surface 19 gentle. That is, the inclination angle β of the inner inclined surface portion 18 is gentle, and the angle of the boundary portion between the inner inclined surface portion 18 and the rolling sliding surface 19 (complement angle of the inclination angle β) approaches 180 degrees. As a result, the concentration of N at the boundary due to the soft nitriding treatment is alleviated, and the generation of the protrusions 9 as shown in FIGS. 6 and 7 is eliminated or alleviated.
When the inclination angle β increases beyond 15 degrees, the angle of the boundary portion decreases (below 165 degrees), and the protrusions are easily formed at the boundary portion. On the other hand, when the inclination angle β is smaller than 3 degrees, the outer inclined surface portion 17 having an inclination angle α steeper than the inner inclined surface portion 18 is provided, but the fall amount δ of the chamfered portion 21a described below is reduced. It becomes difficult to secure. Therefore, the inclination angle β of the inner inclined surface portion 18 is set in the range of 3 to 15 degrees. More preferably, if the inclination angle is set in a range of 4 to 7 degrees, the generation of the protrusions and the securing of the drop amount δ can be more effectively achieved.

Similarly, regarding the boundary portion between the outer inclined surface portion 17 and the inner inclined surface portion 18, the angle of the boundary portion (complement angle of the difference “α−β” between the inclination angles of both the inclined surface portions 17 and 18) is close to 180 degrees. Therefore, the generation of the protrusion 9 is eliminated or alleviated.
In addition, since the boundary portion between the both inclined surface portions 17 and 18 exists at a position slightly depressed from the rolling sliding surface 19, the boundary portion is rarely in direct contact with the mating surface. Therefore, the formation of some protrusions at the boundary portion is unlikely to be a practical problem as compared with the boundary portion between the inner inclined surface portion 18 and the rolling sliding surface 19. Therefore, the inclination angle α of the outer inclined surface portion 17 is not particularly limited, but it is unrealistic to increase the inclination angle beyond 45 degrees, and should be within 30 degrees or less.
However, it is preferable that the protrusions are not generated even at the boundary between the inclined surface portions 17 and 18. Therefore, the inclination angle α of the outer inclined surface portion 17 is set so that the difference “α−β” between the inclined surface portions 17 and 18 falls within the range of 3 to 15 degrees {α = β + (3 to 15 degrees. ). In addition, regarding the boundary portion between the both inclined surface portions 17 and 18, it is only necessary to suppress the generation of the ridge (it is not necessary to prevent it completely). On the contrary, in order to ensure the drop amount δ, It is necessary to increase the inclination angle α of the inclined surface portion 17. Therefore, the difference “α−β” between the inclined surfaces 17 and 18 may be set larger within the above range (for example, within a range of 10 to 15 degrees).

Also, can reduce the axial dimension L ₂₁ of the chamfered portion 21a, the inclination angle of the chamfered portion 21a is changed in two steps, the inclination angle α of the outer inclined surface portion 17 that exists in the edge side relatively steep You can plan by doing.
That is, as described above, the fall amount δ of the edge of the chamfered portion 21a from the rolling sliding surface 19 is for improving the efficiency of assembling work of the rolling sliding parts or for the rolling sliding surface 19 and the mating surface. It is necessary to secure a certain amount in order to ensure that the lubricating oil can be taken in between the two.
In the case of the above-described prior invention, as shown in FIG. 10, the inclination angles θ _i and θ _{o of the} chamfered portions 13 and 14 on the inner diameter side and the outer diameter side are gentle over the entire width of the chamfered portions 13 and 14. And it was constant. Therefore, in order to secure the drop amount δ, it is necessary to increase the axial lengths L _i and L _o of the chamfered portions 13 and 14.
On the other hand, in the case of the present invention, since the inclination angle α of the outer inclined surface portion 17 away from the rolling sliding surface 19 is made relatively steep, the axial dimension L ₂₁ of the chamfered portion 21a is set to be smaller. Even if it is shortened, the drop amount δ can be secured.
Incidentally, with respect to the axial dimension L ₂₁ of the chamfered portion 21a, the ratio of the inner inclined surface portion defines the design in relation to the drop amount δ in need, but 30 to 60% can be considered realistic .

  As a preferred embodiment for carrying out the present invention, the inner and outer peripheral surfaces of the inner diameter side roller 6 of the cam follower device for a valve mechanism of a double roller type engine as shown in FIGS. Can be considered. In this case, with respect to the outer peripheral surface of the inner diameter side roller 6, as described in claim 2 of the claims, the rolling sliding surface is a cylindrical outer peripheral surface, and the chamfered portion faces the edge. As the outer diameter becomes smaller, a partially conical convex surface is formed. The inclination angle of the inner inclined surface with respect to the central axis of the outer peripheral surface is set to 3 to 15 degrees, preferably 4 to 7 degrees.

As for the inner peripheral surface of the inner diameter side roller 6, as described in claim 3 of the claims, the rolling sliding surface is a cylindrical inner peripheral surface, and the chamfered portion faces the edge. As the outer diameter increases, a partially conical concave surface is formed. The inclination angle of the inner inclined surface with respect to the central axis of the inner peripheral surface is set to 3 to 15 degrees, preferably 4 to 7 degrees.
FIG. 2 shows the shape of the inner peripheral surface of a ferrous alloy material processed to actually manufacture the inner diameter side roller 6. FIGS. 2A and 2B are obtained by measuring the same part of the same inner diameter side roller 6 but have different magnifications. That is, the magnification of the horizontal axis (the axial direction of the inner diameter side roller 6) is 10 times in both cases (A) and (B), but regarding the vertical axis (the diameter direction of the inner diameter side roller 6), A) is 1000 times and (B) is 50 times.
When a material as shown in FIGS. 2A and 2B is made and the surface of this material is soft-nitrided, the inner inclined surface is also applied to the boundary portion between the rolling sliding surface and the inner inclined surface portion. The protrusions 9 as shown in FIGS. 6 to 8 were not formed at the boundary portion between the surface portion and the outer inclined surface portion, and the effects of the present invention could be confirmed.

  The above description has been mainly focused on the case where the present invention is applied to a roller for a cam follower device for an engine valve mechanism. However, the present invention is not limited to such a roller, and can be implemented, for example, with respect to a chamfered portion formed at an axial end portion of a rolling surface of a roller for a roller bearing. Of course, a single roller type structure in which only one roller is provided can also be implemented. Furthermore, the present invention can also be carried out for a component in which a surface that is in sliding contact with the mating surface is a convex curved surface or a flat surface, and a chamfered portion is formed at the end of this surface.

The schematic diagram for demonstrating this invention. The figure which similarly shows one example of specific bus-bar shape. The partial expanded sectional view which shows an example of the cam follower apparatus for valve operating mechanisms of an engine. FIG. 4 is a partial cross-sectional view showing a structure in which a soft nitriding layer is formed on the surface of an inner diameter side roller, as viewed from the same direction as FIG. FIG. 5 is a view similar to FIG. 4 showing a structure in which a soft nitriding layer is formed on the surfaces of both the inner diameter side and outer diameter side rollers. The schematic diagram which shows the state in which a protrusion is produced | generated by the surrounding surface of a roller. The figure which similarly shows one example of specific bus-bar shape. The diagram which shows the change of the bus-bar shape of each part after operating by incorporating the roller which has this specific shape. The schematic diagram for demonstrating the reason a protrusion is produced | generated by the surrounding surface of a roller. Sectional drawing which shows the structure of the prior invention considered in order to prevent that this protrusion is produced | generated.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Camshaft 2 Cam 3 Rocker arm 4 Support wall part 5 Support shaft 6 Inner diameter side roller 7 Outer diameter side roller 8 Material 9 Projection 10, 10a Lubricant film 11 Cylindrical surface part 12 Roller 13 Inner diameter side chamfering part 14 Outer diameter side chamfering 14 Part 15 Inner diameter side cylindrical surface part 16 Outer diameter side cylindrical surface part 17 Outer inclined surface part 18 Inner inclined surface part 19 Rolling sliding surface 20 Soft nitriding layer 21, 21a Chamfered part

Claims (3)

  It is made of an iron-based alloy and has a rolling sliding surface that makes rolling contact or sliding contact with the mating member. At the edge of this rolling sliding surface, the closer to the edge, the closer to the center of this rolling sliding surface. A rolling sliding part manufacturing method comprising a chamfered portion inclined in a dent direction, and a soft nitriding layer formed on the chamfered portion and the surface portion of the rolling sliding surface. In the state before performing the soft nitriding treatment, the chamfered portion is located on the edge side, the outer inclined surface portion having a steep inclination angle with respect to the central portion of the rolling sliding surface, and the center of the rolling sliding surface. An inner inclined surface portion that is located on the near side and has a gentle inclination angle with respect to the central portion of the rolling sliding surface, and the chamfered portion including both the outer and inner inclined surface portions and the rolling sliding surface, Form nitrocarburized layer Method for manufacturing a sliding component rolling with a soft-nitriding the applied process for that.   The rolling sliding surface is a cylindrical outer peripheral surface, and is inclined in a direction in which the outer diameter decreases as the chamfered portion approaches the edge, and the inclination angle of the inner inclined surface with respect to the central axis of the outer peripheral surface is 3 to 15 The method of manufacturing a rolling sliding part according to claim 1, wherein   The rolling sliding surface is a cylindrical inner peripheral surface, and the chamfered portion is inclined in a direction in which the outer diameter increases toward the end edge. The inclination angle of the inner inclined surface with respect to the central axis of the inner peripheral surface is 3 The method for manufacturing a rolling sliding part according to claim 1, which is ˜15 degrees.

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