JP2009108901A - Rolling slide face structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rolling slide face structure capable of obtaining excellent friction reduction action. <P>SOLUTION: In the rolling slide face structure with a cross-sectionally recessed curved-like truck surface 4 that a rolling body 1 is rotatively slid, a recessed part 6 extending in a direction intersecting a rolling slide direction of the rolling body 1b is continuously formed in the rolling slide direction on at least one side of the contact passage area B of the rolling body 1 at the truck surface 4. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a rolling sliding surface structure having a raceway surface on which rolling elements roll and slide.

  In order to improve the durability of rolling sliding members such as thrust bearings and cam followers, lubricating oil is interposed between the rolling element and the raceway surface on which the rolling element rolls and slides (hereinafter referred to as an oil film). The friction between the two sliding surfaces is reduced.

  For example, in Patent Document 1, in order to improve the oil film forming ability, fine concave portions are continuously formed on the raceway surface in the rolling and sliding direction of the rolling elements. This concave line portion functions as an oil reservoir for holding lubricating oil, so that an oil film can be sufficiently formed between the raceway surface and the rolling elements. Further, in order to form an oil film that is particularly strong in the rolling sliding direction, the recess is formed to extend in a direction perpendicular to the rolling sliding direction (see FIG. 2 of Patent Document 1). .

  There is a laser processing method as a processing method capable of easily forming the periodic structure of the fine concave portions on the surface of the solid material. Specifically, when the processing surface of a solid material is scanned with a linearly polarized femtosecond laser at a fluence near the processing threshold, a grating-like periodic structure with a submicron periodic pitch and amplitude (height difference) is self-organized. (For example, refer nonpatent literature 1).

  FIG. 10 is a schematic diagram of the periodic structure creation device. A femtosecond laser L is irradiated from the laser generator 400 onto the mirror-polished surface of the solid material Z on the stage 500. The laser energy can be adjusted using the half-wave plate 600 and the polarization beam splitter 700, and is condensed by the lens 800 and irradiated onto the surface of the solid material Z.

When the surface of the solid material Z is irradiated with a pulse laser, interference between the p-polarized component of the incident light and the p-polarized component of the surface scattered light occurs, resulting in energy density at the laser wavelength interval on the laser irradiation surface. When the fluence of incident light is near the laser threshold, only the high energy portion is selectively ablated. Once the ablation is started and the surface roughness is increased, the intensity of the surface scattered light is increased at the time of the next laser irradiation, the ablation is further advanced, and interference occurs at a position one wavelength λ away. When the incident light is linearly polarized light, repeated laser irradiation causes interference at approximately the same interval as the wavelength λ of the incident light, thereby creating a grating-like periodic structure in a self-organized manner. The periodic structure can be extended over a wide range on the surface of the solid material Z by scanning the pulse laser while overlapping it.
JP-A-2005-32148 Sawada Hiroshi, Kawahara Kosuke, Ninomiya Takafumi, Kurosawa Hiroshi, Yokoya Atsushi: Formation of Fine Periodic Structures with Femtosecond Laser, Journal of Precision Engineering, 69, 4, (2003) 554.

  However, as in Patent Document 1, even if the concave strip extending in the direction orthogonal to the rolling sliding direction is continuously formed on the raceway surface, there may be a case where a satisfactory friction reducing action cannot be obtained. Hereinafter, this will be described with reference to FIG.

  11A is a cross-sectional view of a conventional rolling sliding surface structure, and FIG. 11B is a plan view thereof. In FIGS. 11A and 11B, reference numeral 100 denotes a spherical body as a rolling element, and reference numeral 200 denotes a raceway surface having a concave curved cross section on which the spherical body 100 rolls and rolls. As shown in FIG. 11B, a concave strip 300 extending in the direction perpendicular to the rolling sliding direction is continuously formed on the entire raceway surface 200 in the rolling sliding direction.

  The spherical body 100 contacts at the center (bottom) in the width direction of the raceway surface 200, and a contact surface (contact ellipse) between the spherical body 100 and the raceway surface 200 is indicated by a hatched portion A in FIG. When the sphere 100 rolls and slides along the raceway surface 200, the region indicated by reference sign B becomes a contact passage region through which the sphere 100 passes while contacting the raceway surface 200.

  On both sides of the contact passage area, slip occurs between the rolling and sliding sphere and the raceway surface, and this slip generates dynamic pressure in the lubricating oil in the concave portion extending in the direction perpendicular to the rolling and sliding direction. Then, the lubricating oil is affected by the dynamic pressure due to the sliding, and is drawn between the ridges between the ridges between the ridges on the raceway surface. As a result, on both sides of the contact passage region, the lubricating oil can be interposed between the raceway surface (specifically, the convex strips between the concave strips) and the sphere, and an oil film can be formed.

  On the other hand, in the contact passing region, the sphere rolls purely, and slip hardly occurs between the sphere and the raceway surface, so that the dynamic oil due to the slip is hardly generated in the lubricating oil in the concave portion of the contact passing region. Therefore, in the contact passage region, even if the concave strip portion is formed, the oil film forming action due to the slip as described above cannot be obtained. Further, in the contact passing region, the lubricating oil drawn into the contact passing region flows out along the concave strip portion when the sphere rolls and slides. For these reasons, in the contact passage region, it is considered that the frictional force is increased by forming the concave stripe portion, and thus there is a problem that the friction reducing action as the entire raceway surface cannot be effectively obtained.

  Then, in view of the said subject, this invention provides the rolling sliding surface structure which can obtain a favorable friction reduction effect | action.

  The invention according to claim 1 is a rolling sliding surface structure having a concave curved raceway surface on which the rolling element rolls and slides, and the rolling element is provided on at least one side of a contact passing region of the rolling element on the raceway surface. The concave strip and / or the convex strip extending in the direction intersecting with the rolling sliding direction are continuously formed in the rolling sliding direction.

  As used herein, “continuously” means that the concave and / or convex ridges are formed at an equal pitch in the rolling sliding direction, or an unequal pitch or a partly long pitch, in other words. Including those formed intermittently.

  In the configuration of claim 1 above, at least one side of the contact passage region where slippage occurs (between the rolling and rolling rolling elements and the raceway surface) is provided with a groove (and / or Ridges). When dynamic pressure is generated in the lubricating oil held in the concave portions (or the gaps between the convex portions) due to the slip, the lubricating oil is affected by the dynamic pressure due to the sliding, and the convex portions between the concave portions are projected. It is drawn and interposed between the strip and the rolling element. Thereby, an oil film is sufficiently formed between the raceway surface and the rolling elements. On the other hand, in the contact passing region where slip hardly occurs (between the rolling element that rolls and slides and the raceway surface), no concave strip (and / or convex strip) is formed. Thereby, it is possible to prevent the lubricating oil drawn into the contact passage region by rolling and sliding of the rolling elements from flowing out of the contact passage region along the concave strip portion, and the oil film is also formed in the contact passage region. Can be formed. Thus, the rolling sliding surface structure of the present invention can obtain a good friction reducing action on the entire raceway surface.

  A second aspect of the present invention is the rolling sliding surface structure according to the first aspect, wherein the concave and / or convex ridges are formed at least on one side of the contact passage region and separated from the contact passage region. It is what.

  That is, the concave strip (and / or the convex strip) is formed so as to avoid a contact passage region where an oil film forming action due to sliding cannot be obtained. Thereby, in the contact passage region, it is possible to effectively prevent the lubricating oil drawn by the rolling elements from rolling and sliding, and to form an oil film.

  The invention according to claim 3 is the rolling sliding surface structure according to claim 1 or 2, wherein the groove extends in a direction crossing the rolling sliding direction so as to be completely included in the contact area, and The ridges are formed continuously in the rolling sliding direction.

  By arranging the concave strip (and / or the convex strip) so as to be completely included in the contact passage region, the concave strip (or the gap between the convex strips) is allowed to roll with the raceway surface. Sealed by the contact surface with the moving body. Thereby, when a rolling element rolls and slides on a raceway surface, it can prevent that lubricating oil flows out along a concave strip part (or clearance gap between convex strip parts).

  According to a fourth aspect of the present invention, in the rolling sliding surface structure according to any one of the first to third aspects, the concave strip portion and / or the convex strip portion extend in a direction perpendicular to the rolling sliding direction. Is.

  When the concave strip (and / or the convex strip) is formed so as to be inclined with respect to the rolling sliding direction, depending on the direction in which the rolling element rolls and slides, the concave strip (or the convex strip mutual space) In some cases, the lubricating oil held in the gap) flows out of the raceway surface along the recess (and / or the protrusion). On the other hand, as described in claim 4, the rolling elements are rolled and slid in one direction of the raceway surface by extending the concave ridges (and / or ridges) in a direction orthogonal to the rolling sliding direction. In either case, or in the case of rolling and sliding in both directions of the raceway surface, it is possible to suppress the lubricant oil from flowing out along the concave strip portion (and / or the convex strip portion).

  A fifth aspect of the present invention is the rolling sliding surface structure according to any one of the first to fourth aspects, wherein the pitch of the concave stripe portion and / or the convex stripe portion is set to 1 μm or less.

  Thereby, the lubricating oil retention capability of the groove (and / or the protrusion) is improved, and the lubricant is prevented from flowing out along the groove (or the gap between the protrusions). Can do.

  A sixth aspect of the present invention is the rolling sliding surface structure according to any one of the first to fifth aspects, wherein the raceway surface is irradiated with a linearly polarized laser beam at a fluence in the vicinity of a processing threshold, and an irradiated portion thereof Are scanned while being overlapped, and the concave portion is rolled in a self-organized manner and continuously formed in the sliding direction.

  Thereby, formation of a concave part becomes easy.

  According to the rolling sliding surface structure of the present invention, the concave strip portion (and / or the convex strip portion) having an oil reservoir function is formed on at least one side of both sides of the contact passage region where dynamic pressure due to sliding is likely to occur. By doing so, generation | occurrence | production of dynamic pressure is accelerated | stimulated and an oil film can fully be formed. On the other hand, in the contact passage region where the dynamic pressure due to slipping is unlikely to occur, by not forming the concave portion (and / or the convex portion), it is possible to prevent the lubricating oil from flowing out and form an oil film. Thus, the rolling sliding surface structure of the present invention can obtain a good friction reducing action on the entire raceway surface. Further, by not forming the concave strip (and / or the convex strip) that causes stress concentration in the contact passage region, it is possible to prevent the occurrence of cracks and breakage.

Hereinafter, an embodiment in which the configuration of the present invention is applied to a rolling sliding surface of a thrust bearing will be described as an example.
FIG. 1 is a cross-sectional view of a thrust bearing. As shown in FIG. 1, the thrust bearing includes a plurality of spherical rolling elements 1, a pair of annular thrust receiving seats 2, 2, and an annular holding body 3 interposed between the thrust receiving seats 2, 2. Have The plurality of rolling elements 1 are held at equal intervals in the circumferential direction by the holding body 3. An annular raceway surface 4 is formed on each of the opposing surfaces of the pair of thrust receiving seats 2, 2, and the rolling element 1 rolls and slides along the raceway surface 4.

  In FIG. 1, the raceway surfaces 4 of the pair of thrust receiving seats 2 and 2 disposed on the upper side and the lower side are similarly configured. Hereinafter, the structure will be described by taking the raceway surface 4 of the lower thrust seat 2 as an example.

  2 is an enlarged cross-sectional view of the raceway surface 4 of the lower thrust seat 2 shown in FIG. As shown in FIG. 2, the cross-sectional shape of the raceway surface 4 is formed in a concave arc shape.

  FIG. 3 is a plan view of the raceway surface 4 and shows the first embodiment of the present invention. The raceway surface 4 is actually formed in an annular shape, but in FIG. 3, the raceway surface 4 is illustrated in a straight line for convenience.

  In this embodiment, the rolling element 1 contacts at the center (bottom) in the width direction of the raceway surface 4. A contact surface (contact ellipse) where the rolling element 1 and the raceway surface 4 are in contact is indicated by a hatched portion A in FIG. Moreover, in the same figure, the area | region shown with the code | symbol B is a contact passage area | region through which the said contact surface A passes, when the rolling element 1 rolls along the track surface 4. FIG.

  And so that the contact passage area | region B may be avoided, the fine groove part 6 is continuously formed in the rolling sliding direction on the both sides. Here, the “rolling sliding direction” is a direction in which the rolling element 1 rolls along the raceway surface 4, and the vertical direction (vertical direction) in FIG. 3 is the rolling sliding direction. Moreover, this recessed strip part 6 is extended in the direction orthogonal to a rolling sliding direction.

  What is necessary is just to form the said grooved part 6 using the apparatus shown in FIG. Specifically, a linearly polarized laser beam is irradiated at a fluence in the vicinity of the processing threshold on the planned processing portion (on both sides of the contact passage region B) of the track surface 4 whose surface has been mirror-finished. The irradiation portion is scanned while being overlapped to form the periodic structure of the concave portion 6 in a self-organizing manner. Moreover, it is desirable that the pitch (of the periodic structure) of the concave strips 6 is 1 μm or less. The reason for this will be described later in the rolling sliding test.

  On the other hand, in the contact passage region B, the concave stripe portion 6 is not formed, and the surface treatment is still performed in a smooth surface or a mirror surface.

  FIG. 4 shows a second embodiment of the present invention. In this embodiment, the inner ends of the concave strips 6 formed on both sides of the contact passing area B enter the contact passing area B. FIG. 5 shows a third embodiment of the present invention. In the third embodiment, the concave strips 6 formed on both sides of the contact passing area B are isolated from the contact passing area B.

  As shown in FIG. 4 and FIG. 5, the width W of the region (smooth surface portion) where the recess 6 is not formed may be set smaller than the width X of the contact passage region B, or It may be set larger than the width X. However, it is preferable to set the lower limit value of the width W of the region (smooth surface portion) where the concave strip portion 6 is not formed to 0.5 times the width X of the contact passage region B. The upper limit of the width W is preferably set to twice the width X of the contact passage area B. The reason for setting the lower limit value and the upper limit value will also be described in the later-described rolling sliding test.

  4 and 5, the reference numerals other than the reference numerals described above and the same reference numerals as those in FIG. 3 have the same configurations as those in FIG.

  FIG. 6 shows a fourth embodiment of the present invention. As shown in FIG. 6, fine concave portions 6 are continuously formed in the rolling sliding direction on both sides of the contact passage region B. Also, in the contact passage region B, fine concave strips 6 are continuously formed in the rolling and sliding direction. The recess 6 formed in the contact passing area B is disposed so as to be completely included in the contact passing area B. Between the periodic structure of the concave portion 6 completely included in the contact region B and the periodic structure of the concave portion 6 disposed on both sides of the contact passage region B, the concave portion 6 is formed, respectively. An unsmoothed or mirror-like part is interposed. In FIG. 6, the reference numerals other than the reference numerals described above and the same reference numerals as those in FIG. 3 have the same configurations as those in FIG.

The inventor conducted a rolling sliding test of the thrust bearing. Hereinafter, this rolling sliding test will be described.
FIG. 7 is a simplified diagram of the test apparatus. This test apparatus includes an upper jig 11 for holding a thrust seat 2 on one side (upper side in the figure) of a thrust bearing 10 and a lower jig 12 for holding the thrust seat 2 on the other side (lower side in the figure). . The rolling element 1 can be rolled and slid along the track surface 4 by rotating the upper jig 11 with respect to the lower jig 12. At this time, the rolling friction coefficient generated between the rolling element 1 and the raceway surface 4 is measured. The test apparatus also includes an air cylinder 13 for applying a load in the axial direction to the rolling element 1.

  In this test, five types of thrust bearings were prepared. (A)-(e) of FIG. 8 is a top view of each track surface 4 of these five types of thrust bearings. 8A to 8E, the vertical direction is the rolling sliding direction, and the horizontal direction is the width direction of the raceway surface 4 orthogonal to the rolling sliding direction.

  FIG. 8A shows a raceway surface 4 to which the rolling sliding surface structure of the present invention is applied. On the raceway surface 4, recessed strips 6 extending in the lateral direction are continuously formed in the longitudinal direction on both sides of the contact passage region B (in the center in the width direction).

  (B)-(e) of FIG. 8 is a comparative example with the bearing of this invention of (a). In Comparative Example 1 shown in (b), the concave strip portion 6 extending in the lateral direction is continuously formed in the longitudinal direction on the entire surface of the raceway surface 4. In Comparative Example 2 shown in (c), the concave strip 6 extending in the vertical direction is continuously formed in the horizontal direction on the entire surface of the raceway surface 4. Moreover, the comparative example 3 shown to (d) forms the groove part 6 extended in the horizontal direction continuously in the vertical direction in the contact passage area | region B (center of the width direction) of the track surface 4. As shown in FIG. Both ends of the concave stripe portion 6 are formed so as to protrude somewhat from the contact passage region B. In Comparative Example 4 shown in (e), in the contact passage region B (in the center in the width direction) of the raceway surface 4, a concave strip portion 6 extending in the vertical direction is continuously formed in the horizontal direction. In addition, in (a), (d), (e), the part which does not form the concave-line part 6 of the track surface 4 is processed into the smooth surface shape or the mirror surface shape.

  The depth and pitch of each recess 6 are similarly formed. Specifically, the depth of the recess 6 is set to 150 to 200 nm and the pitch is set to about 700 nm. Turbine oil was used as the lubricating oil to be filled in each raceway surface 4.

A method for measuring rolling friction will be described.
First, in the various bearings shown in FIGS. 8A to 8E, the pair of thrust receiving seats 2 and 2 are fixed to the upper jig 11 and the lower jig 12 of the test apparatus, and rolled by the air cylinder 13. A load in the axial direction is applied to the moving body 1. Next, the rolling element 1 is rolled along the track surface 4 by rotating the upper jig 11 with respect to the lower jig 12. Before measuring the rolling friction, the rolling body 1 is rotated at a rotational speed of 2.4 m / s (about 59π rad / s) for 30 minutes to stabilize the temperature of the rolling element 1. Thereafter, the rolling friction coefficient generated between the rolling element 1 and the raceway surface 4 is measured while gradually decreasing the rotation speed.

  In this test, in each of the bearings shown in FIGS. 8A to 8E, the rolling frictions before and after forming the concave strip portion 6 were measured.

  FIG. 9 shows the measurement results of rolling friction. 9A to 9E correspond to the bearings of FIGS. 8A to 8E. In the graphs shown in FIGS. 9A to 9E, the vertical axis represents the friction coefficient generated between the rolling element 1 and the raceway surface 4, and the horizontal axis represents the rotational speed. The data plotted with circles indicates the friction coefficient before processing the concave strip 6, and the data plotted with triangles indicates the friction coefficient after processing the concave strip 6.

  First, the measurement results of Comparative Example 1 shown in FIG. As can be seen from the graph shown in FIG. 9 (b), the friction coefficient (triangular plot) after processing the concave section 6 is reduced to some extent from the friction coefficient (round plot) before processing the concave section 6. ing.

  When the rolling element 1 rolls along the raceway surface 4, slip occurs between the rolling element 1 and the raceway surface 4 on both sides of the contact passage region B. When slipping occurs, dynamic pressure is generated in the lubricating oil held in the concave strip portion 6, and the lubricating oil is affected by the dynamic pressure due to the sliding, and the convex strip portion between the concave strip portions 6 and the rolling element It is drawn between and intervenes. Thereby, an oil film is formed between the raceway surface 4 and the rolling element 1 on both sides of the contact passage region B.

  On the other hand, in the contact passage region B, the rolling element 1 rolls purely, so that there is almost no slip between the raceway surface 4. Therefore, even if the concave strip portion 6 is formed in the contact passage region B, an oil film forming action due to slippage cannot be obtained in the concave strip portion 6. Further, in the contact passing region B, it is considered that the rolling oil 1 that has received a load in the axial direction presses the raceway surface 4 so that the lubricating oil has flowed out along the concave strip 6. For these reasons, it is inferred that the friction coefficient increased in the contact passage region B, and the friction surface reducing action was not effectively obtained for the entire raceway surface 4.

  In Comparative Example 2 shown in FIG. 8 (c), as shown in FIG. 9 (c), there is almost no difference between the friction coefficient before processing the concave strip 6 and the friction coefficient after processing. In Comparative Example 2, the concave strip portion 6 extends so as to be parallel to the rolling sliding direction, and therefore, the lubricating oil held by the concave strip portion 6 is less likely to generate dynamic pressure due to slipping. Further, the lubricating oil retention capability is low as compared with the concave strip portion 6 extending in the orthogonal direction. From this, it is considered that Comparative Example 2 shown in FIG. 8C did not provide a friction reducing action as compared with Comparative Example 1 shown in FIG.

  Further, in Comparative Example 3 and Comparative Example 4 shown in FIGS. 8 (d) and 8 (e), as shown in FIGS. 9 (d) and 9 (e), the friction coefficient after machining the recess 6 is both. The (triangular plot) greatly increased the coefficient of friction of the concave strip 6 before processing (circle plot). In Comparative Example 3 and Comparative Example 4, the concave portion 6 is formed in the contact passage region B, but in the contact passage region B, an oil film forming action due to slipping cannot be obtained. In addition, it is considered that the lubricating oil has flowed out along the concave strip portion 6 when the rolling element 1 presses the contact passage region B. For these reasons, it is presumed that the coefficient of friction has increased.

  In contrast to the test results of the comparative examples of FIGS. 8B to 8E, the embodiment of the present invention shown in FIG. 8A has a concave portion as shown in FIG. The friction coefficient after processing 6 (triangular plot) has a greater effect of reducing the friction coefficient especially in the high speed region than the friction coefficient before processing the concave strip 6 (circle plot).

  In the embodiment of the present invention, the concave stripe portions 6 are formed on both end sides of the contact passage region B of the raceway surface 4. When the rolling element 1 rolls on the raceway surface 4, slip occurs between the rolling element 1 and both ends of the contact passage region B. When dynamic pressure is generated in the lubricating oil held by the concave strip 6 due to the slip, the lubricating oil is affected by the dynamic pressure due to the slip, and the gap between the convex strip between the concave strips 6 and the rolling elements. Is drawn into and intervenes. As a result, an oil film is sufficiently formed between the raceway surface 4 and the rolling element 1 at both ends of the contact passing region B.

  On the other hand, in the contact passage region B, since slip hardly occurs, an oil film forming action due to slip cannot be obtained. However, since the concave portion 6 is not formed in the contact passage region B, the lubricating oil drawn by the rolling sliding of the rolling element 1 flows out from the contact passage region B along the concave portion 6. There is no. Thereby, an oil film can be formed between the contact passage region B of the raceway surface 4 and the rolling element 1. For the above reason, it is presumed that the embodiment of the present invention can form a sufficient oil film over the entire raceway surface 4 and can effectively reduce the friction.

  Further, in the rolling sliding structure of the present invention, the width of the region (smooth surface portion) where the concave stripe portion 6 is not formed is set to the lower limit value of W to 0.5 times the width X of the contact passage region B. This is to suppress an increase in friction in the contact passage region B. That is, if the width W is smaller than the lower limit value, the amount of the recessed portion 6 entering the contact passage region B increases, and the lubricating oil easily flows out along the recessed portion 6.

  Moreover, when the upper limit of W is set to twice the width X of the contact passage region B, the width of the region (smooth surface portion) where the recess 6 is not formed exceeds the upper limit. This is because the range formed by the portion 6 is reduced, and it is difficult for dynamic pressure due to sliding to occur.

  Although not shown in the drawings, in the experiment, the width W of the region (smooth surface portion) where the concave stripe portion 6 is not formed is in a range of 0.5 times or more and 2 times or less the width X of the contact passage region B ( In 0.5X ≦ W ≦ 2X), a clear friction reducing effect was recognized after the formation of the concave strip portion. However, when the width W of the region (smooth surface portion) where the concave portion 6 is not formed is more than three times the width X of the contact passage region B (W ≧ 3X), before the concave portion is formed and the concave portion There was almost no difference in friction reduction effect after formation.

  Further, by setting the pitch of the periodic structure of the concave strip portion 6 to 1 μm or less, the lubricating oil retention capability of the concave strip portion 6 is enhanced, and the lubricant oil is prevented from flowing out along the concave strip portion 6. Is possible.

  In the embodiment shown in FIG. 6, the concave strip portion 6 is continuously formed in the contact passage region B, that is, in a place where dynamic pressure due to sliding is difficult to occur. For example, in the comparative example shown in FIG. 8 (d), the rolling element 1 that has received a load in the axial direction presses the center in the width direction of the raceway surface 4, so that the lubricating oil flows out along the recess 6. To do. However, in the embodiment of FIG. 6, the concave strip portion 6 is formed so as to be completely included in the contact passage region B, so the concave strip portion 6 is a contact surface (hatching portion) between the rolling element 1 and the raceway surface 4. Sealed by A). Thereby, the outflow of the lubricating oil from the concave strip portion 6 can be prevented, and the retaining ability of the lubricating oil can be maintained. Moreover, in this embodiment, in the periodic structure of the concave strip portion 6 formed on both sides of the contact passage region B and the non-formed portion (smooth surface portion) of the concave strip portion 6, the implementation of FIG. It is possible to obtain the same action as the friction reducing action in the embodiment.

  As mentioned above, although one Embodiment of this invention was described, this invention is not limited to the above-mentioned embodiment, Of course, a various change can be added in the range which does not deviate from the summary of this invention. In the above-described embodiment of the present invention, the case where the rolling sliding surface structure of the present invention is applied to a thrust bearing has been described as an example. However, the configuration of the present invention is not limited to a linear raceway surface or a barrel-shaped outer periphery. The present invention can also be applied to a raceway surface on which a roller having a surface can roll, or a raceway surface having a cross-sectional Gothic arch shape or an elliptical shape in which a rolling element contacts at two points (angular contact).

  The concave portion may be formed only on one side of the contact passage region. Further, the concave stripe portion is not limited to the case of extending in the direction orthogonal to the rolling sliding direction, but may be extended in a direction inclined with respect to the rolling sliding direction. It is also possible to form a concavo-convex surface on the raceway surface by forming a ridge portion instead of the ridge portion, or by combining the ridge portion and the ridge portion.

It is sectional drawing of a thrust bearing. It is the figure which expanded the raceway surface of the thrust bearing of FIG. It is a top view which shows 1st Embodiment of the rolling sliding surface structure of this invention. It is a top view which shows 2nd Embodiment of the rolling sliding surface structure of this invention. It is a top view which shows 3rd Embodiment of the rolling sliding surface structure of this invention. It is a top view which shows 4th Embodiment of the rolling sliding surface structure of this invention. It is a simplified diagram of a rolling sliding test apparatus. It is a figure which shows five types of track surfaces used for a rolling sliding test, Comprising: (a) is a top view of the track surface of this invention, (b)-(e) is a top view of the track surface of a comparative example. . It is a graph which shows the measurement result of a rolling sliding test, Comprising: (a) is a graph which shows the measurement result of this invention, (b)-(e) is a graph which shows the measurement result of a comparative example. It is a schematic diagram of a periodic structure creation apparatus. It is a figure which shows the conventional rolling sliding surface structure, Comprising: (a) is the sectional drawing, (b) is the top view.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rolling body 4 Track surface 6 Concave strip B Contact passage area W Width X Width

Claims (6)

In the rolling sliding surface structure having a raceway surface having a concave curved cross section where the rolling element rolls and slides,
On at least one side of the contact passage region of the rolling element on the raceway surface, a concave strip and / or a convex strip extending in a direction intersecting the rolling sliding direction of the rolling element is continuously provided in the rolling sliding direction. A rolling sliding surface structure characterized by being formed.   The rolling sliding surface structure according to claim 1, wherein the concave stripe portion and / or the convex stripe portion is formed on at least one side of the contact passage region and separated from the contact passage region.   The concave and / or convex ridges extending in a direction crossing the rolling and sliding direction are formed continuously in the rolling and sliding direction so as to be completely included in the contact area. Rolling sliding surface structure as described in 1.   The rolling sliding surface structure according to any one of claims 1 to 3, wherein the concave and / or convex strips extend in a direction orthogonal to the rolling sliding direction.   The rolling sliding surface structure according to any one of claims 1 to 4, wherein a pitch of the concave stripe portion and / or the convex stripe portion is set to 1 µm or less.   The track surface is irradiated with a linearly polarized laser beam at a fluence near the processing threshold, and the irradiated portion is scanned while being overlapped, and the concave strip portion is continuously organized in the rolling sliding direction in a self-organizing manner. The rolling sliding surface structure according to any one of claims 1 to 5, wherein the rolling sliding surface structure is formed.

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