JP2010164158A - Lubrication structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lubrication structure that has an improved lubrication function by effectively utilizing an oil-repellent treatment in forming and maintaining an oil film. <P>SOLUTION: In the lubrication structure, which oil-films and lubricates a contact region 3 where two relatively moving members 1 are loaded into contact with each other, at least either one member 1 of the two members 1 is provided with an oil-repellent treatment portion 4 to which an oil-repellent treatment repellent to lubricating oil is applied in a portion adjoining the contact region 3 in the one member 1. The lubricating oil repelled by the oil-repellent treatment portion 4 is positively supplied to the contact region 3 and the lubricating oil is contained in the contact region 3 by the oil-repellent treatment portion 4 to promote the effect of maintaining the lubricating oil and resultant oil film in the contact region 3. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a lubrication structure at a location where two members contact via an oil film.

  Lubricating is usually performed at portions where high-hardness members such as metal are in contact with each other under load, in order to perform smooth relative motion with each other and to suppress wear. Specifically, the lubricating oil is supplied so as to form an oil film between the contact surfaces. However, it is difficult to supply the lubricating oil locally only between the contact surfaces. However, the lubricating oil is pressurized and sprayed near the contact surface, or the lubricating oil scraped up by the rotating member is used. It is made to descend toward the contact surface. Therefore, in the mechanical apparatus having this type of lubrication point, the inside becomes wet by the scattered or flowing lubricating oil, and a part of the rotating member is immersed in the oil reservoir to stir the lubricating oil. .

  When gears, rollers, drive shafts, etc. rotate with lubricating oil attached, or when the lubricating oil is stirred by immersion in an oil reservoir, power loss occurs due to the viscous resistance of the lubricating oil, or shear force acts on the lubricating oil. As a result, the temperature rises and deterioration progresses. Thus, for example, Patent Document 1 describes that an oil repellent treatment is performed on a surface that comes into contact with the lubricating oil and does not come into contact with another power transmission member, such as an outer peripheral surface of a clutch drum partially immersed in an oil reservoir. . Patent Document 2 describes that an oil repellent treatment is applied to the outer peripheral surface of the bearing portion in order to prevent the lubricating oil from being scattered by the centrifugal force from the power roller in the toroidal-type continuously variable transmission. Yes. Furthermore, Patent Document 3 describes that an oil-repellent treatment is performed on the rolling surface of the bearing to prevent adhesion of the lubricating oil and the accompanying kinematic viscosity resistance or torque loss.

JP 2008-25677 A Japanese Patent Laid-Open No. 2004-84690 Japanese Patent Laid-Open No. 2007-40428

  The oil repellency treatment is a treatment for forming a film having oil repellency such as tetrafluoroethylene on the metal surface, and the film repels lubricating oil, so that it is described in Patent Document 1 and Patent Document 3 described above. Furthermore, adhesion and drag of the lubricating oil can be reduced. This is to avoid or suppress the lubricant from adhering to locations that do not require lubrication due to the lubricant being widely scattered or flowing inside the housing or the like in various mechanical devices. Technology. In other words, it does not promote the lubrication effect or the effect of forming and maintaining the oil film. Further, as described in Patent Document 2, if oil repellent treatment is performed on the outer peripheral portion away from the rotation center of the rotating member, when centrifugal force acts on the lubricating oil, the portion subjected to the oil repellent treatment The action which keeps lubricating oil on the inner circumference side of can be obtained. However, the technique described in Patent Document 2 is a technique that prevents or suppresses the lubricant oil from flying away due to centrifugal force until it gets tired, and does not provide a lubrication effect or an effect of forming and maintaining an oil film. In this way, conventionally, even if the oil repellent treatment is performed, there is no function of actively supplying the lubricating oil to the contact portion of the two members that move relative to each other or holding the oil film, thereby promoting the lubricating effect. There was still room for improvement.

  The present invention has been made paying attention to the above technical problem, and provides a lubrication structure capable of improving the lubrication function by effectively applying an oil repellent treatment for forming and maintaining an oil film. It is intended to do.

  In order to achieve the above object, the invention according to claim 1 is directed to a lubricating structure in which lubrication is performed by forming an oil film in a contact portion where two relatively moving members apply loads and contact each other. Of at least one of the two members, an oil repellent treatment portion that has been subjected to an oil repellent treatment that repels lubricating oil is formed at a location adjacent to the contact portion of the one member. It is a feature.

  The invention according to claim 2 is the lubricating structure according to claim 1, wherein the oil repellent treatment portion is provided in a state of surrounding the contact portion.

  According to a third aspect of the present invention, in the first or second aspect of the invention, the contact portion is provided on a surface of a predetermined flat surface portion or curved surface portion with the edge portion as a boundary, and at least one of the contact portion and the edge portion. The lubricating structure is characterized in that an oil introduction portion that is connected to the portion and not subjected to the oil repellent treatment is further provided.

  According to a fourth aspect of the present invention, in any one of the first to third aspects, an oil repellency treatment is applied to one of the contact portions of the two members, and an oil repellency is applied to the other contact portion. The lubricating structure is characterized in that it is not treated.

  According to a fifth aspect of the present invention, in any one of the first to fourth aspects, the two members include a gear that meshes teeth with each other and transmits torque, and the contact portion is formed on a tooth surface of the gear. It is a lubricating structure characterized by being made.

  A sixth aspect of the present invention is the lubricating structure according to the fifth aspect of the present invention, wherein the oil introducing portion is connected to one end portion in the tooth width direction of the tooth surface.

  The invention according to claim 7 is the invention according to any one of claims 1 to 4, wherein the two members include an inner race or an outer race and a roller that rolls in contact with the inner race or the outer race. The contact portion includes a crowning surface that is formed on a convex curved surface facing the roller and contacts the roller, and a cylindrical outer peripheral surface of the roller, and the oil repellent treatment portion is formed on the outer peripheral surface of the roller. Of these, the lubricating structure is characterized in that it is formed at a position not in contact with the crowning surface on at least one end side in the axial direction.

  The invention of claim 8 is the invention according to any one of claims 1 to 4, wherein the two members are arranged in a predetermined housing and rotate or move in the axial direction and an outer peripheral surface of the shaft member. A sealing material that shuts off the inside and the outside of the housing in a liquid-tight state by contacting with each other. And a lubrication structure provided at a portion located inside the housing.

  According to the first aspect of the present invention, when the lubricating oil is supplied toward the contact portion where the two members are contacted by receiving a load, the lubricating oil adheres to the contact portion to form an oil film. On the other hand, since the lubricating oil is repelled by the oil repellent treatment part adjacent to the contact part, the flow of the lubricating oil from the contact part to the oil repellent treatment part is suppressed, and the lubrication reaching the oil repellent treatment part At least a portion of the oil is repelled toward the contact portion. As a result, since the lubricating oil is positively held in the contact portion, the amount of the lubricating oil can be ensured, or the formation and maintenance of the oil film can be promoted to effectively perform the lubrication. In addition, even if relative movement between the oil repellent portion and the lubricating oil occurs, the oil repellent portion is prevented from sticking to the so-called lubricating oil. Accordingly, power loss can be suppressed.

  According to the invention of claim 2, in addition to the same effect as that of the invention of claim 1, the lubricating oil is unlikely to flow away in any direction around the contact portion. Or an oil film can be hold | maintained more effectively.

  According to the invention of claim 3, in addition to the same effect as that of the invention of claim 1 or 2, the lubricating oil flowing along the surface of the flat surface portion or the curved surface portion is guided from the oil introduction portion to the contact portion. Therefore, the lubricating oil or oil film at the contact portion can be held more effectively.

  According to the invention of claim 4, in addition to the same effects as the effects of the inventions of claims 1 to 3, either one of the contact portions that are in contact with each other has been subjected to oil repellent treatment, so either one of them It is possible to prevent the lubricating oil from sticking to the contact portion that has been subjected to the oil repellent treatment or to drag the lubricating oil, and as a result, it is possible to prevent or suppress power loss, an increase in oil temperature, and the like. Moreover, the oil film between each contact part can be formed and maintained when the other contact part which has not been subjected to the oil repellent treatment holds the lubricating oil.

  According to the invention of claim 5, in addition to the same effects as those of the inventions of claims 1 to 4, the gears are effectively lubricated to improve the power transmission efficiency, and the durability of the gears and the lubricating oil is improved. Can be improved.

  According to the invention of claim 6, in addition to the effect similar to the effect of the invention of claim 5, the lubricating oil can be effectively introduced into the contact portion on the tooth surface.

  According to the seventh aspect of the invention, in addition to the same effects as the first to fourth aspects of the invention, the roller bearing can be lubricated effectively and the durability of the roller bearing and the lubricating oil can be improved. Can be made.

  According to the invention of claim 8, in addition to the same effects as those of the inventions of claims 1 to 4, the seal portion can be lubricated effectively and the durability of the seal portion and lubricating oil is improved. Can be made.

It is a typical front view which shows one of the tooth surfaces of the helical gear to which this invention is applied. It is a fragmentary view for explaining a meshing part in a tooth surface of a helical gear. It is a Stribeck diagram showing the coefficient of friction of the tooth surface with and without the oil repellent treatment part according to the present invention. It is a front view which shows typically the other example of the tooth surface of the helical gear to which this invention is applied. It is sectional drawing which shows a part of roller bearing to which this invention is applied. It is a partial sectional view showing an example of another roller bearing to which the present invention is applied. It is a fragmentary sectional view showing an example of the seal part to which this invention is applied. It is a partial side view for demonstrating the example of the one way clutch which performed the oil-repellent process on the outer surface.

  Next, the present invention will be described more specifically. The present invention relates to a structure in which an oil film is formed by a lubricating oil in a contact portion under a load, and lubrication is performed. Therefore, a member that comes in contact via the oil film is a member that moves relatively. Specific examples are a one-way clutch that transmits torque via rolling elements such as gears, bearings, and sprags, and a seal structure. The relative motion is mainly sliding or rolling with friction. In these members, so-called contact portions that contact each other under a load are limited regions, and in the present invention, the oil repellent treatment portions are subjected to oil repellent treatment at locations adjacent to the contact portions of the limited regions. Is provided. The oil-repellent treatment is a treatment for forming a film of a fluororesin such as polytetrafluoroethylene (PTFE), or a treatment having a fine unevenness on the surface and a coating of the fluororesin (referred to as a super oil-repellent treatment). This is a conventionally known process.

  The oil repellent portion having such a configuration may be formed at a location adjacent to the contact portion. Since this oil repellent treatment part is for repelling the lubricant and pushing the lubricant to adjacent locations, the width or width of the oil repellent treatment part is determined by whether the lubricant or its oil droplets are The width or width is such that the oil-repellent portion is not covered across the surface, and this can be determined by experiment according to the lubricant to be used. Further, the oil repellent portion may be formed in an annular shape so as to surround the contact portion, or may be formed only on one side (one side portion) sandwiching the contact portion, and further, a part thereof is opened. It may be formed in an annular shape.

  Therefore, in the lubrication structure having such a configuration, the contact portion is relatively oleophilic and the oil repellent treatment portion adjacent to the contact portion is oil repellency, so that the lubricating oil in the contact portion is repelled by the oil repellent treatment portion. To be held in the contact area. That is, since the lubricating oil is positively held at the contact portion, it is possible to avoid or suppress insufficient lubrication, oil film breakage, etc., and perform effective lubrication. In addition, a part of the lubricating oil that has descended toward the contact portion or has reached the oil repellent treatment portion is repelled by the oil repellent treatment portion and pushed to the contact portion adjacent thereto. Therefore, the supply of the lubricating oil to the contact portion is promoted, and effective lubrication can be performed also in this respect. That is, the oil-repellent treatment part functions positively for supplying lubricating oil to the contact part and forming an oil film. In addition, since the lubricating oil is difficult to adhere to the oil repellent portion, the lubricating oil is hardly dragged or stirred by the oil repellent portion, and as a result, so-called stirring resistance and accompanying power loss can be reduced.

  FIG. 1 schematically shows an example in which the present invention is applied to a helical gear. FIG. 1 shows a state in which a tooth surface 2 of one tooth 1 is viewed from a direction perpendicular to the tooth surface 2. The upper end portion in FIG. 1 is a tooth tip A, and the lower end portion in FIG. Is the tooth root D. A helical gear is a gear formed so that teeth are twisted with respect to the central axis, and therefore the meshing of the teeth between the driving gear and the driven gear is one end in the width direction. The meshing location changes toward the other end, and changes from the tooth tip A side to the tooth root D side or from the tooth root D side to the tooth tip A side. In FIG. 2, the meshing portion is indicated by a line on the tooth surface 2.

  The location where the tooth surfaces actually contact each other is an area having a width wider than the width indicated by the line in FIG. 2, and this area corresponds to the contact portion 3 in the present invention. The non-contact portion adjacent to the contact portion 3 is provided with an oil repellent treatment portion 4 that has been subjected to oil repellent treatment. In FIG. 1, it is described as a region with cross hatching. The non-contact portion where the oil repellent treatment portion 4 is provided is a portion of the tooth surface 2 where contact between the teeth 1 does not occur. And the oil-repellent treatment part 4 is formed in an annular shape so as to surround the entire outer peripheral side of the contact part 3 with a width that does not cover the lubricating oil. Although only one tooth 1 is shown in FIG. 1, the oil-repellent treatment part 4 surrounding the contact part 3 is formed on all the teeth in the driving and driven gears that mesh with each other. Preferably it is.

  Therefore, in the gear provided with the oil repellent treatment portion 4 as shown in FIG. 1, when the lubricating oil falls on the tooth surface 2 or when the lubricating oil flows to the tooth surface 2 through the gear, the tooth surface 2 is once. Lubricating oil may adhere to the entire surface. However, in the oil repellent treatment unit 4, the lubricating oil is repelled by the oil repellent action on the surface, and the lubricant is pushed to both sides of the oil repellent treatment unit 4. Since the oil repellent portion 4 is formed adjacent to the contact portion 3 as described above, part of the lubricating oil pushed away from the oil repellent portion 4 is sent to the contact portion 3. That is, the oil repellent treatment unit 4 acts to supply lubricating oil to the contact unit 3. On the other hand, the lubricating oil tends to spread to the surface to which the lubricating oil adheres due to its surface tension, but such an action occurs in the contact portion 3, but in the oil repellent treatment portion 4 adjacent to the contact portion 3. The surface tension is generated in the opposite direction to the contact portion 3, and as a result, the lubricating oil in the contact portion 3 is prevented or suppressed from spreading to the oil repellent treatment portion 4.

  In this way, the lubricating oil in the oil repellent treatment unit 4 is positively supplied to the contact parts 3 in which the teeth 1 receive a load and contact each other, and the lubricating oil in the contact part 3 is supplied by the oil repellent treatment part 4. It is held by the contact portion 3. Therefore, in the configuration shown in FIG. 1, so-called escape of the lubricating oil in the contact portion 3 is prevented, and the lubricating oil or oil film is maintained in the contact portion 3. That is, it is possible to satisfactorily lubricate the tooth surface 2, particularly where the teeth 1 are in contact with each other, and to reduce the friction coefficient μ at the time of meshing. This will be explained using a Stribeck diagram. The solid line in FIG. 3 shows the friction coefficient μ of the tooth surface where the oil repellent treatment part 4 is not provided, and the broken line shows the oil repellent treatment part 4 provided. The friction coefficient μ of the tooth surface is shown. As shown in FIG. 3, when the oil repellent treatment portion 4 is provided and the lubricating oil and the oil film are positively held in the contact portion 3, the fluid lubrication area increases and the friction at the time of meshing can be reduced. .

  In addition, in the structure shown in FIG. 1, since the load accompanying torque transmission between gears does not act on the oil-repellent treatment part 4 provided with a coating such as a fluorine-based resin, the durability of the oil-repellent treatment part 4 is excellent. It will be a thing. Further, since the oil repellent treatment unit 4 does not cause or reduces the adhesion of the lubricating oil, the accompanying dragging of the lubricating oil, or the shearing action on the lubricating oil, the so-called agitation resistance of the lubricating oil can be reduced, and the lubricating oil can be reduced. Heat generation and durability can be suppressed. In the configuration shown in FIG. 1, since the area of the oil repellent portion 4 may be small, the cost can be reduced when the contact portion 3 is effectively lubricated.

  FIG. 4 shows an example in which the configuration shown in FIG. 1 is improved. The example shown here is an example in which the supply of the lubricating oil to the contact portion 3 is promoted and the spread of the lubricating oil or oil film at the contact portion 3 is promoted. Specifically, FIG. 4 schematically shows the teeth 11 of the driving gear which is a helical gear and the teeth 12 of the driven gear meshing with the teeth, and the teeth 11 and 12 approach each other. The part which is doing is tooth top A11, A12, and the part on the opposite side is tooth base D11, D12. And in the example shown in FIG. 4, lubricating oil (oil) is supplied from the left side in FIG. The supply of the lubricating oil is performed by an appropriate rotating member (not shown) adjacent to the gears scooping up the lubricating oil, or the scooped-up lubricating oil flows down. Then, the teeth 11 and 12 start to mesh from the end side to which the lubricating oil is supplied, and the meshed portions change in an oblique direction as indicated by arrows in FIG.

  The tooth surfaces 13 and 14 of the teeth 11 and 12 are surfaces defined by the tooth tips A11 and A12 and the tooth bases D11 and D12 and the edge portions on both ends in the tooth width direction. A contact portion 3 is provided so as to cross the central portion of the oil cartridge obliquely, and an oil repellent treatment portion 4 is provided so as to surround the contact portion 3. The contact portion 3 and the oil repellent treatment portion 4 have basically the same configuration as the example shown in FIG. 1 described above, and are provided in an oblique direction along the movement locus of the meshing portion. In the example shown in FIG. 4, the oil repellent treatment portion 4 is cut open at the end portions of the tooth surfaces 13 and 14 on the meshing start side, and the portion not subjected to the oil repellent treatment is the tooth width from the contact portion 3. It is formed so as to reach an edge portion on one end side in the direction (meshing start end side). Accordingly, the portion not subjected to the oil repellent treatment is the oil introduction portion 15 in the present invention.

  Also in the configuration shown in FIG. 4, the lubricating oil supplied and adhered to the contact portion 3 is repelled by the oil repellent treatment portion 4 provided adjacent to the contact portion 3 and surrounding the contact portion 3. So-called escape of the lubricating oil from the portion 3 is prevented or suppressed. Of the lubricating oil supplied to the tooth surfaces 13, 14, the lubricating oil that has reached the oil-repellent treatment section 4 is pushed away from the oil-repellent treatment section 4 by its oil-repellent action, and one of the pushed lubricant oils. Part is supplied to the contact part 3. Since the lubricating oil is positively held and supplied in this way to the contact portion 3 where the teeth 11 and 12 contact each other under a load, the friction coefficient when the teeth 11 and 12 are engaged with each other is reduced. Can be made.

  In the configuration shown in FIG. 4, the contact portion 3 that has not been subjected to the oil repellent treatment is connected to the edge portion on the oil supply side via the oil introduction portion 15, and the contact portion 3 supplies oil. It has a so-called open (open) configuration on the side. Therefore, the lubricating oil supplied toward the tooth surfaces 13 and 14 is guided to the contact portion 3 through the oil introduction portion 15 without being repelled by the oil repellent treatment portion 4. Therefore, the supply of lubricating oil to the contact portion 3 is facilitated. Since the location where the lubricating oil is supplied in this way is the meshing start point of the teeth 11, 12 or a location close thereto, the lubricating oil moves along the contact portion 3 as the meshing of the teeth 11, 12 progresses. Moved and pushed again. The direction is the direction indicated by the arrow in FIG. Thus, the oil introduction part 15 is formed, whereby the supply of lubricating oil to the contact part 3 can be promoted. In other words, the tooth surfaces 13 and 14 can be effectively lubricated. Therefore, even if the total amount of lubricating oil or the total amount of supply is reduced, the tooth surfaces 13 and 14 can be lubricated satisfactorily. Therefore, the amount of lubricating oil is reduced to reduce the resistance and power loss associated with the stirring. Can be reduced.

  Next, an example in which the present invention is applied to a bearing will be described. FIG. 5 shows a part of a roller bearing to which the present invention is applied. Between the inner race 31 and the outer race 32, a plurality of cylindrical or columnar rollers 33 are arranged. It is held by a retainer 34. The outer circumferential surface of the inner race 31, that is, the rolling surface 35 that contacts the roller 33, and the inner circumferential surface of the outer race 32, that is, the rolling surface 36 that contacts the roller 33, are crowned toward the roller 33. On the other hand, the outer peripheral surface of the roller 33 has a simple cylindrical shape, a columnar shape, or a tapered shape. Accordingly, the rolling surfaces 35 and 36 which are crowning surfaces are in contact with the substantially central portion in the axial direction of the outer peripheral surface of the roller 33, and the portions on both end sides in the axial direction of the outer peripheral surface of the roller 33 are The rolling surfaces 35 and 36 are not in contact with each other. This is to reduce the power loss by reducing the contact area between the roller 33 and the inner race 31 that operate relatively and the contact area between the roller 33 and the outer race 32.

  Therefore, in the example shown in FIG. 5, the contact portion 37 is the central portion of the outer peripheral surface of the roller 33 that contacts the rolling surfaces 35 and 36 under load. Then, the oil repellent treatment is performed on the portions on both ends in the axial direction adjacent to the contact portion 37, that is, on the outer peripheral surface of the roller 33, the portion not in contact with the rolling surfaces 35, 36. 38 is formed.

  Therefore, in the bearing shown in FIG. 5, the lubricating oil supplied between the inner race 31 and the outer race 32 adheres to the respective rolling surfaces 35 and 36 and the rollers 33. Of the lubricating oil adhering to the outer peripheral surface of the roller 33, the lubricating oil that has reached the oil-repellent treatment portion 38 is pushed away from the oil-repellent treatment portion 38 due to its oil-repellent action, and a part thereof is supplied to the contact portion 37. . Further, since the lubricating oil in the contact portion 37 is repelled by the oil repellent processing portion 38 adjacent to the contact portion 37, it is prevented or suppressed from spreading out of the contact portion 37. As described above, also in the roller 33 in the bearing shown in FIG. 5, the lubricating oil is positively applied to the contact portion 37 by the action of the oil repellent treatment portion 38 as in the case of the gear tooth surface shown in FIG. 1 or FIG. Supplied and held. Therefore, even if the rolling surfaces 35 and 36 are crowned and the contact pressure with the rollers 33 is high, the lubricating oil is sufficiently supplied and maintained, so that the boundary lubrication state is achieved. Can expand and reduce the coefficient of friction. As a result, coupled with the effect of crowning, power loss can be reduced and durability can be improved. Further, as in the case of the gear described above, it is possible to reduce the agitation of the lubricating oil and the accompanying resistance and power loss.

  In the configuration shown in FIG. 5, the roller 33 is sandwiched between the inner race 31 and the outer race 32, and the oil-repellent treatment portions 38 are formed on both end sides in the axial direction, so that an oil film is formed. Further, the contact portion 37 that needs to hold the oil film is shielded against or close to the lubricating oil around the bearing. In order to eliminate the shielding state, it is preferable to configure as shown in FIG. That is, in FIG. 6, the roller 33 is a conical roller, and the center axis thereof is held in a state where it is inclined at a predetermined angle with respect to the center axis of the bearing. An oil repellent portion 38 is provided on one end side in the axial direction of the outer peripheral surface of the roller 33, and an oil repellent treatment is not performed on the opposite end portion side, so that the contact portion 37 is provided. It is comprised so that it may become lipophilic like. This lipophilic part corresponds to the oil introduction part in the present invention. The oil repellent treatment portion 38 is formed on the end side having a large revolution radius with respect to the rotation center of the bearing, and the end portion not subjected to the oil repellent treatment is an end having a relatively small revolution radius with respect to the rotation center of the bearing. Part.

  When relative rotation occurs between the inner race 31 and the outer race 32, the roller 33 rotates, so that the rotation radii at both ends in the axial direction of the roller 33 are different. , 36 is subjected to a force flowing toward a location having a large radius with respect to the rotation center of the bearing. Along with this, lubricating oil enters from the end portion side having a relatively small turning radius in the roller 33, and an action of flowing this oil to the end portion side having a relatively large turning radius occurs. Since the oil repellent process is not performed on the one end portion side of the roller 33 into which the lubricating oil flows in this way, the lubricating oil is smoothly supplied or supplied to the contact portion 37. On the other hand, since the oil repellent treatment part 38 is formed on the end side from which the lubricating oil flows out, that is, the end part having a large turning radius, the lubricating oil flowing from the contact part 37 on the end side is oil repellent. The processing unit 38 is pushed and stopped. That is, so-called escape of the lubricating oil from the contact portion 37 is prevented or suppressed. Therefore, in the configuration shown in FIG. 6, the supply of the lubricating oil to the contact portion 37 of the roller 33 is promoted, and escape from the contact portion 37 is prevented or suppressed, so that the lubricating oil or oil film is effectively applied to the contact portion 37. As a result, the lubricating performance can be improved, the power loss can be reduced, and the durability can be improved.

  Still another example of the present invention will be described. The example shown in FIG. 7 is an example of a seal portion to which the present invention is applied, and a seal material 41 for maintaining liquid tightness is attached to an opening of a casing (not shown). The inner diameter of the lip portion 42 of the sealing material 41 is the smallest, and the shaft 43 is disposed so as to be in sliding contact with the inner peripheral surface of the lip portion 42. In FIG. 7, the left side is the inside of the casing, filled with lubricating oil, or the lubricating oil is scattered or flowing. On the other hand, the right side in FIG. 7 is the outside of the casing, and is open to the atmosphere as an example.

  Therefore, the inner peripheral surface of the lip portion 42 is in sliding contact with the shaft 43, so that the liquid tightness is maintained so that the lubricating oil does not leak from the casing to the outside. The shaft 43 is a rotating shaft, or a slide shaft that moves back and forth in the axial direction. A contact portion 44 is a portion of the outer peripheral surface where the lip portion 42 of the sealing material 41 is in sliding contact. An oil repellent treatment in which oil repellent treatment is applied to a portion adjacent to the contact portion 44, more specifically, a portion of the outer peripheral surface of the shaft 43 located inside the casing and adjacent to the contact portion 44 A portion 45 is provided. The oil-repellent treatment part 45 is formed in the entire circumference of the shaft 43 in a band shape having a predetermined width. In other words, even if it is a location adjacent to the contact portion 44, a location that is open to the atmosphere is not subjected to oil repellent treatment.

  Accordingly, when configured as shown in FIG. 7, the lubricating oil in the vicinity of the seal portion is repelled by the oil repellent treatment portion 45 in the shaft 43, and a part of the lubricant oil is applied to the lip portion 42 of the seal material 41. It is supplied to the contact portion 44 that is in contact. Further, the lubricating oil in the contact portion 44 is repelled by the oil repellent processing portion 45 adjacent thereto, and so-called escape of the lubricating oil in the contact portion 44 is prevented or suppressed. Since the lubricating oil is positively supplied and held in this way in the contact portion 44, the frictional resistance between the shaft 43 and the sealing material 41 is reduced, power loss and heat generation, and the accompanying sealing material 41. And the deterioration of the durability of the lubricating oil can be prevented or suppressed. Further, since the lubricating oil is difficult to adhere to the oil-repellent treatment part 45 and easily separated, the agitation and dragging of the lubricating oil accompanying the rotation and back-and-forth movement of the shaft 43 can be reduced. Can be prevented or suppressed.

  In each of the specific examples described above, the oil-repellent treatment portion is formed at a location adjacent to the contact portion and not in frictional contact with other members, but in the present invention, in addition to such a configuration, they are in contact with each other. An oil repellent treatment portion may be formed by applying an oil repellent treatment to any one of the two surfaces. For example, the oil repellent treatment is not performed on the contact portion on one tooth surface of the drive gear and the driven gear, and the oil repellent treatment is performed on the contact portion on the other tooth surface. Even in such a configuration, the lubricating oil is positively supplied to one of the contact portions and the oil film is held, so that the lubrication is not hindered. In addition, since the lubricating oil is repelled at the contact portion of the other tooth surface, dragging of the lubricating oil at the contact portion is mitigated, and accordingly, resistance and power loss caused by dragging of the lubricating oil can be reduced. it can.

  By the way, if an oil repellent treatment is performed, adhesion of lubricating oil can be prevented or suppressed as described in Patent Document 1, and stirring and dragging of the lubricating oil can be reduced. Therefore, in the present invention, in addition to the oil repellent portion in each of the specific examples described above, the oil repellent treatment may be performed on the surface that comes into contact with the lubricating oil. For example, FIG. 8 shows an example of a one-way clutch, in which a plurality of rollers 53 having a circular cross section are sandwiched between an inner race 51 and an outer race 52, and these rollers 53 are held at regular intervals by a retainer 54. Is retained. Therefore, rolling surfaces (contact portions in the present invention) 55 and 56 that come into contact with the rollers 53 are formed on the outer peripheral surface of the inner race 51 and the inner peripheral surface of the outer race 52. The rolling surface 56 in the outer race 52 is formed as a curved surface that smoothly connects a portion where the distance from the outer peripheral surface of the inner race 51 is smaller than a diameter of the roller 53 and a larger portion.

  Therefore, when a torque is applied between the inner race 51 and the outer race 52 in a direction in which the rollers 53 are spaced apart from each other by a distance smaller than the diameter of the rollers 53, the inner race 51 and the outer race 52 are separated from each other. The race 52 is connected via a roller 53, and a torque can be transmitted between them. That is, the clutch is engaged. When torque acts in the opposite direction, the roller 53 moves to a location where the distance between the rolling surfaces 55 and 56 is larger than the diameter of the roller 53. Therefore, the inner race 51 and the outer race 52 via the roller 53 Is uncoupled.

  Each of the rolling surfaces 55 and 56 acting in this way is not subjected to an oil repellent treatment in order to maintain the oil film by adhering lubricating oil. The outer surface such as the surface and the side surface of the retainer 54 are subjected to oil repellent treatment. In FIG. 8, the part which has been subjected to the oil repellent treatment is shown with cross hatching. Accordingly, since the lubricating oil is repelled and the lubricating oil does not adhere at the places where these oil repellent treatments are performed, so-called stirring resistance and drag resistance can be reduced.

  1,11,12 ... tooth, 2,13,14 ... tooth surface, A, A11, A12 ... tooth tip, D, D11, D12 ... tooth base, 3, 37, 44 ... contact part, 4, 38, 45 ... Oil repellent treatment part, 15 ... Oil introduction part, 31 ... Inner race, 32 ... Outer race, 33 ... Roller, 34 ... Retainer, 35, 36 ... Rolling surface, 41 ... Sealing material, 42 ... Lip part, 43 ... Shaft .

Claims (8)

In a lubrication structure that lubricates by forming an oil film at a contact portion where two relatively moving members apply a load and contact each other,
Of at least one of the two members, an oil-repellent treatment portion that has been subjected to an oil-repellent treatment that repels lubricating oil is formed at a location adjacent to the contact portion of the one member. Lubrication structure characterized by   The lubricating structure according to claim 1, wherein the oil repellent portion is provided in a state of surrounding the contact portion. The contact portion is provided on the surface of a predetermined flat surface portion or curved surface portion with the edge portion as a boundary,
The lubricating structure according to claim 1, further comprising an oil introduction portion that is connected to the contact portion and at least a part of the edge portion and is not subjected to the oil-repellent treatment.   4. The oil repellent treatment is performed on one contact portion of the contact portions of the two members, and the oil repellent treatment is not performed on the other contact portion. 2. Lubrication structure as described in   The said two members are gears which mesh | engage a tooth | gear mutually and transmit a torque, The said contact part is formed in the tooth surface of the gearwheel, The Claim 1 thru | or 4 characterized by the above-mentioned. Lubrication structure.   The lubricating structure according to claim 5, wherein the oil introduction portion is connected to one end portion in the tooth width direction of the tooth surface. The two members include an inner race or an outer race and a roller that rolls in contact with the inner race or the outer race,
The contact portion includes a crowning surface that is formed on a convex curved surface facing the roller and contacts the roller, and an outer peripheral surface of the roller that has a cylindrical shape,
2. The oil repellent treatment portion is formed on a portion of the outer peripheral surface of the roller that is at least one end in the axial direction and does not contact the crowning surface. 4. The lubricating structure according to any one of 4 above. The two members are arranged in a predetermined housing, and rotate or move in the axial direction to contact the outer peripheral surface of the shaft member and shut off the inside and the outside of the housing in a liquid-tight state. Including sealing material,
5. The oil repellent treatment portion is provided in a portion of the outer peripheral surface of the shaft member that is adjacent to a contact portion with which the sealing material contacts and is located inside the housing. The lubricating structure according to any one of the above.

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