JP2011117524A - Lubrication structure of rotating member - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lubrication structure of a rotating member, improving the oil repellent performance of an oil repellent treatment part and improving the durability of the same. <P>SOLUTION: In the lubrication structure of the rotating member 7, at least a part of the rotating member 7 is oil-bathed in lubrication oil lubricating the rotating member 7 and the oil repellent treatment part 10 for repelling the lubrication oil is provided on at least the part of the rotating member 7. On the side face of the rotating member 7, an irregularity structure is formed for roughening the side face and the oil repellent treatment part 10 coated with a low surface tension treating agent is provided. An air bubble mixing means (ribs 9) for mixing air bubbles with the lubrication oil is further provided on the side face of the rotating member 7 formed with the oil repellent treatment part 10. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a lubricating structure for a rotating member lubricated by lubricating oil.

  Normally, rotating members such as gears, rollers, or drive shafts are lubricated for smooth operation and for suppressing wear. However, if these rotating members are immersed in an oil reservoir, and the lubricating oil is scraped up and lubricated by the rotating member, power loss occurs due to the viscous resistance of the lubricating oil, and shearing force acts on the lubricating oil. The temperature rises and a situation such as deterioration of the lubricating oil occurs. Therefore, in Patent Document 1, an oil repellent treatment portion is provided on the surface of the rotating member to repel the oil and reduce the rotation of the oil, thereby reducing the rotational resistance of the rotating member. Is described. More specifically, the surface of the rotating member is coated with polytetrafluoroethylene having oil repellency. For this reason, even if the surface of the rotating member comes into contact with the oil oil surface, the oil is repelled in a short time by the coating, so that the oil rotation due to the stirring of the oil of the rotating member is reduced, heat generation of the oil and rotation of the rotating member The resistance is reduced.

  Patent Document 2 describes that a metal surface is roughened by etching, and a water- and oil-repellent film made of a hydrophobic resin containing fine particle powder is applied to the roughened surface. Furthermore, Patent Document 3 describes that when engine oil is at a predetermined temperature or lower, the viscosity of the oil is reduced by mixing a micro valve into the oil.

JP 2008-25677 A JP-A-10-156282 Japanese Patent Laid-Open No. 2007-24011

  The oil repellency treatment is a treatment for forming a film having oil repellency such as tetrafluoroethylene on the surface of the rotating member, and the film repels lubricating oil, as described in Patent Document 1 above, Lubricant adhesion and drag can be reduced. The oil repellent portion can similarly reduce the adhesion and dragging of the lubricating oil even at the outer peripheral portion such as a counter gear or a differential gear. However, when the oil repellent treatment is performed on the contact portion between these gears and other rotating members that rotate relative to each other, that is, the meshing portion, the oil repellent treatment portion may be deteriorated in durability due to wear. The oil repellent portion needs to be applied to a non-contact portion between the rotating member and another rotating member. That is, the technique described in Patent Document 1 is a technique for reducing or suppressing the amount of lubricating oil that accompanies the rotating member until tired. Further, as described in Patent Document 2, if the roughened surface is subjected to water / oil repellent treatment, a highly durable water / oil repellent property due to a synergistic effect of the fine uneven structure and the hydrophobic resin. Can be obtained. However, there is a possibility that oil penetrates into the uneven structure and the oil repellency is lowered. Furthermore, the technique described in Patent Document 3 is to reduce the friction of the internal combustion engine and the transmission by reducing the viscosity of the engine oil by mixing microbubbles into the engine oil. Thus, conventionally, there is no function for improving the oil repellency effect of the oil repellent treatment portion and maintaining the effect, and there is still room for improvement.

  The present invention has been made paying attention to the above technical problem, and an object of the present invention is to provide a lubricating structure for a rotating member capable of improving the oil repellency effect of the oil repellent treatment portion and the maintenance of the effect. Is.

  In order to achieve the above object, the invention of claim 1 is characterized in that at least a part of the rotating member is bathed in a lubricating oil that lubricates the rotating member, and at least a part of the rotating member includes the lubricant. In a lubricating structure of a rotating member provided with an oil repellent treatment part that repels oil, an uneven structure for roughening the side surface is formed on the side surface of the rotating member, and a low surface tension treatment agent is coated. The oil repellent treatment section is provided, and a bubble mixing means for mixing bubbles in the lubricating oil is further provided on a side surface of the rotating member on which the oil repellent treatment section is formed. .

  The invention of claim 2 is characterized in that, in the invention of claim 1, the bubble mixing means includes a wing-shaped rib provided on a side surface of the rotating member and projecting in a rotating direction of the rotating member. This is a lubricating structure of the rotating member.

  A third aspect of the present invention is the invention according to the first or second aspect, wherein the bubble mixing means is provided on a side surface of the rotating member, and a plurality of fastening members that fasten the rotating member to a member that rotates integrally with the rotating member. Any one of the plurality of fastening members is provided in the vicinity of the rotation center of the rotating member, and the other plurality of fastening members are provided in the vicinity of the outer peripheral edge of the rotating member. It is a lubrication structure of a rotating member.

  According to a fourth aspect of the present invention, at least a part of the rotating member is bathed in a lubricating oil that lubricates the rotating member, and at least a part of the rotating member is provided with an oil repellent treatment portion that repels the lubricating oil. In the lubricating structure of the rotating member, the rotating member includes a helical gear, and the side of the helical gear on the side where the teeth are released from meshing with the teeth of other helical gears. In addition, an uneven structure for roughening the side surface is formed, and the oil-repellent treatment portion coated with a low surface tension treatment agent is provided.

  According to the first aspect of the present invention, the oil repellent portion is formed on the side surface of the rotating member, and the bubble mixing means for mixing bubbles in the lubricating oil is formed on the side surface of the rotating member on which the oil repellent portion is formed. Is provided. Therefore, on the side surface of the rotating member subjected to the oil repellent treatment, the air bubbles mixed in the lubricating oil by the air bubble mixing means are supplied to the oil repellent treatment portion. Further, the fluid resistance (viscosity resistance) of the lubricating oil is reduced by the bubbles. Furthermore, since the bubble mixing means is provided on the side surface of the rotating member, the mixing ratio of bubbles into the lubricating oil increases as the number of rotations of the rotating member increases. As a result, compared with the case where only the oil-repellent treatment portion is formed on the side surface of the rotating member, it is possible to reduce the accompanying oil on the side surface of the rotating member and to reduce the stirring loss. That is, the stirring loss reduction effect is increased and the oil repellency can be improved. In addition, the presence of air bubbles on the side surface of the rotating member subjected to the oil repellent treatment can improve the durability of the oil repellent treated portion as compared with the case where there are no air bubbles.

  According to the invention of claim 2, in addition to the effect similar to the effect of the invention of claim 1, the bubble mixing means is provided on the side surface of the rotating member and has a blade shape protruding in the rotating direction of the rotating member. Since it is a rib, the mixing of bubbles can be increased as the number of rotations of the rotating member increases. As a result, the bubble mixing rate into the lubricating oil increases, and the stirring loss reduction effect can be improved.

  According to the invention of claim 3, in addition to the effect similar to the effect of the invention of claim 1 or 2, the bubble mixing means fastens the rotating member to another rotating member that rotates integrally with the rotating member. A plurality of fastening members are included, and any one of the plurality of fastening members is provided in the vicinity of the rotation center of the rotating member, and the other plurality of fastening members are provided in the vicinity of the outer peripheral edge of the rotating member. As a result, air bubbles can be supplied uniformly over the entire side surface of the rotating member. That is, the bubble presence rate can be improved even in the vicinity of the rotation center of the rotating member. Therefore, the durability of the oil-repellent treatment portion provided near the rotation center of the rotating member and the oil-repellent treatment portion provided near the outer peripheral edge can be similarly improved.

  According to invention of Claim 4, the oil-repellent processing part is provided in the releasing side of the meshing of the teeth in a helical gear. Therefore, it is possible to supply the air bubbles mixed by the scraping of the lubricating oil by the tooth surface to the surface to which the oil repellent treatment portion is applied. As a result, compared with the case where only the oil-repellent treatment portion is formed on the side surface of the rotating member, it is possible to reduce the accompanying oil on the side surface of the rotating member and to reduce the stirring loss. That is, the stirring loss reduction effect is increased and the oil repellency can be improved. In addition, the presence of air bubbles on the side surface of the rotating member subjected to the oil repellent treatment can improve the durability of the oil repellent treated portion as compared with the case where there are no air bubbles. In addition, since the oil-repellent treatment portion only needs to be provided on the side (surface) that supplies the bubbles, the cost can be reduced.

It is a figure which shows typically the example which applied the bubble mixing means of this invention to the end plate of a differential gear. It is a diagram which shows the correlation with the bubble mixing rate by the end plate in which the blade-shaped rib was formed, and rotation speed. It is a figure which shows typically the uneven structure of the surface of the rotating member in which the oil-repellent process was performed. It is a figure which shows typically the surface state of the oil-repellent processing part when the rotation member provided with the oil-repellent processing part was bathed in lubricating oil. It is a diagram which shows the reduction effect of the stirring loss by this invention. It is a figure which shows typically arrangement | positioning of the some fastening member in the end plate to which this invention is applied. It is a diagram which shows the mixing rate of the bubble in the side surface of the end plate to which this invention is applied. It is a diagram which shows the reduction rate of the stirring loss in the radial direction of the end plate to which this invention is applied. It is a disassembled perspective view of the differential gear which can apply this invention. It is a figure which shows typically the outer shape of the end plate known conventionally. It is a figure which shows typically arrangement | positioning of the fastening member provided in the end plate known conventionally. It is a figure which shows typically scraping up of the lubricating oil by the conventionally known spur gear. It is a figure which shows typically the example which applied this invention to the helical gear. It is a figure which shows typically the example which applied this invention to the helical gear which meshes | engages with the helical gear shown in FIG. 13, and operate | moves relatively. It is a figure which shows typically distribution of a bubble when a bubble is mixed in lubricating oil with the spur gear shown in FIG. It is a figure which shows typically distribution of a bubble when a bubble is mixed in lubricating oil with the helical gear shown in FIG. It is a figure which shows typically distribution of a bubble when a bubble is mixed in lubricating oil with the helical gear shown in FIG. It is a diagram which shows the reduction effect of the stirring loss at the time of applying this invention to the rotating member which the whole was immersed in lubricating oil.

  Next, the present invention will be described more specifically. The present invention relates to a lubricating structure of a rotating member in which at least a part or the entirety of the rotating member is bathed in lubricating oil, and thus the rotating member includes a gear and a power transmission shaft that are bathed in lubricating oil, and These are members that rotate integrally with these rotating members. In the present invention, at least a part or the whole of the rotating member is bathed in the lubricating oil to cause so-called dragging of the lubricating oil, and non-contact with other rotating members that operate (rotate) relative to these rotating members. More specifically, an oil repellent treatment portion is provided in which oil repellent treatment is performed on the side surface of the rotating member. The oil-repellent treatment is a treatment for forming a film of a fluororesin such as polytetrafluoroethylene (PTFE), or has a micro-sized or nano-sized fine unevenness on the surface and is coated with a fluororesin. This is a conventionally known treatment that is configured to repel the lubricating oil by forming an air layer on the surface thereof. The process of forming micro-size or nano-size fine irregularities on the surface of the rotating member to roughen the surface is a conventionally known process such as an etching process, a laser process, or a shot blast process.

  As described above, the oil-repellent treatment portion having such a configuration is formed on a non-contact portion with another rotating member that operates (rotates) relative to the rotating member, more specifically, on the side surface of the rotating member. It only has to be. Since this oil repellent portion is for repelling lubricating oil and reducing dragging of the lubricating oil, the width or width of the oil repellent portion subjected to the oil repellent treatment is determined by the lubricating oil by the rotating member. The width or width is such that the drag can be reduced, and this can be determined in advance by experiments in accordance with the lubricant (oil) to be used and the target rotating member. In addition, the oil repellent portion may be formed on both side surfaces of the rotating member described above, or may be formed only on one side (one side portion), and a part of the oil repellent portion is relatively operated. You may form in the so-called contact part of two rotation members.

  A bubble mixing means for mixing bubbles into the lubricating oil is provided on the side surface of the rotating member that has been subjected to the oil repellent treatment described above. This bubble mixing means reduces the viscosity resistance of the lubricating oil by mixing bubbles in the lubricating oil, and supplies the bubbles to the oil repellent treatment portion, thereby improving the oil repellency performance and durability of the oil repellent treatment portion described above. It is to improve. Therefore, in the present invention, the bubble mixing means may be formed on both side surfaces of the rotating member subjected to the oil repellent treatment described above, or only on one side (one side portion) subjected to the oil repellent treatment. It may be formed. Furthermore, when the rotating member is a gear, the tooth may be the tooth because the tooth scoops up the lubricating oil. More specifically, the bubble mixing means is provided on the side surface of the rotating member that has been subjected to the oil repellent treatment described above, and the wing-shaped rib that protrudes in the rotating direction of the rotating member or the rotating member is rotated to another rotation. The fastening members may be a plurality of fastening members formed in a protruding shape with respect to the side surface of the rotating member. Further, when the rotating member is, for example, a helical gear having teeth formed obliquely with respect to the central axis, the bubble mixing means is the teeth, and the two helical gears that operate relatively. The oil repellent treatment part should just be provided in the side by which the tooth | gear of a gearwheel is released from meshing.

  Therefore, in the lubrication structure of the rotating member having such a configuration, the bubble mixing means is provided on the side surface of the rotating member on which the oil repellent treatment portion is formed, and bubbles are generated on the side surface of the rotating member subjected to the oil repellent treatment. It comes to supply. That is, an air layer is formed on the surface of the oil-repellent treated portion by positively supplying bubbles (air) to the surface of the oil-repellent treated portion, and lubrication by the rotating member is performed by shearing between the air layer and the lubricating oil. Oil drag can be reduced. Moreover, since the viscous resistance of the lubricating oil is reduced by mixing bubbles in the lubricating oil, dragging of the lubricating oil by the rotating member can be reduced. Further, since the bubble mixing means is provided on the side surface of the rotating member or on the teeth of the gear, the mixing ratio of bubbles into the lubricating oil is increased as the number of rotations of the rotating member is increased. That is, the bubble mixing means functions positively so as to mix bubbles in the lubricating oil even when the rotating member rotates at a high speed to generate centrifugal hydraulic pressure. For this reason, an air layer is formed and held in the oil repellent portion by the bubbles mixed in the lubricating oil, so that the stirring loss due to the drag of the lubricating oil can be reduced. And since the lubricating oil is supplied to the rotating member, the oil repellency and durability of the oil repellent portion can be improved.

  FIG. 9 is an exploded perspective view of a differential gear to which the present invention can be applied. The present invention can also be applied to a ring gear, a drive pinion gear, a counter gear, or the like of the differential gear 1. The point is that any part or the whole of the rotating member such as a gear may be oil bathed in the lubricating oil. The differential gear 1 shown in FIG. 9 is conventionally known, and is connected to a power source (not shown) such as an engine or a motor via an input shaft (propeller shaft) so that power can be transmitted. The end of the input shaft is rotatably supported by a predetermined bearing 3 inside the hollow differential carrier 2 and is connected to the drive pinion 4. The drive pinion 4 meshes with the ring gear 5 of the differential gear 1, and a differential case 6 is provided inside the ring gear 5 so that the ring gear 5 and the differential case 6 rotate integrally. A pinion shaft is accommodated in the differential case 6 in parallel with the ring gear 5, and pinion gears are provided at both ends thereof. Further, end plates 7 are respectively provided on both side surfaces (both ends) of the differential case 6 and are fastened to the differential case 6 by fastening members 8 such as a plurality of bolts. Side gears that mesh with the two pinion gears described above are provided on the differential case 6 side of these end plates 7 (that is, inside the end plates). The left and right drive shafts are connected to these side gears so as to rotate integrally. FIG. 10 schematically shows the outer shape of a conventionally known end plate. The plurality of fastening members 8 described above are provided in the vicinity of the outer peripheral edge of the end plate 7. A plurality of ribs 9 are formed from the rotation center side to the outer peripheral edge.

  FIG. 1 schematically shows an example in which the bubble mixing means of the present invention is applied to an end plate of a differential gear. FIG. 1 shows the shape of the outer side of the end plate 7 (the side opposite to the differential case 6 side), and the end plate 7 rotates in the direction indicated by the arrow A, for example. A wing-shaped rib 9 that is curved so as to protrude from the rotation direction is provided on the outer surface. The rib 9 corresponds to the bubble mixing means of the present invention, and as the end plate 7 rotates, the lubricating oil that bathes the end plate 7 is scraped and bubbles are mixed into the lubricating oil. ing. FIG. 2 schematically shows the bubble mixing rate due to the wing-shaped rib, and the bubble mixing rate into the lubricating oil as the rotation speed of the end plate 7 increases as compared with the rib 9 having the conventional shape. Is increasing. In other words, even if the end plate 7 is a region where the centrifugal oil pressure is generated by the rotation, the bubble mixing rate is increased.

  FIG. 3 schematically shows the concavo-convex structure on the surface of the rotating member subjected to the oil repellent treatment. As shown in FIG. 3, the oil-repellent treatment portion 10 has a rough surface formed by continuously forming fine uneven shapes on the surface of the rotating member, and the fine uneven shapes include the recesses and protrusions. For example, it is formed by etching, laser processing, or shot blasting so that the width and height of the film become several μm. From above, for example, fluorine-based processing agents such as polytetrafluoroethylene (PTFE), fluoroalkylsilane, and fluoroalkylmethacrylate having a surface tension of 14 mN / m or less, or silicon-based processing agents such as polydimethylsilicone and paraffin An oil-repellent treatment portion 10 is formed by applying a coating layer 11 such as a system treatment agent. For this reason, relatively small irregularities are formed on the oil droplets of the lubricating oil, and the oil repellency treatment is applied to the surface thereof, which increases the contact angle θ1 of the oil droplets, that is, lubrication. It is designed to repel oil.

  FIG. 4 schematically shows the surface state of the oil repellent treatment portion when the rotating member provided with the oil repellent treatment portion is bathed in lubricating oil. As described above, fine irregularities are formed on the side surface of the rotating member so that the length of one side is several μm, and an oil-repellent treatment agent is applied thereon. Therefore, an air layer 12 is formed between the rotating member and the lubricating oil that bathes the rotating member. As a result, the air layer 12 prevents or suppresses the adhesion of lubricating oil. In other words, when the rotating member rotates, a shearing action is generated between the air layer 12 and the lubricating oil, thereby reducing the drag of the lubricating oil by the rotating member.

  Therefore, in the wing-shaped rib 9 protruding in the rotation direction and the end plate 7 subjected to the oil repellency treatment, bubbles are mixed into the lubricating oil for bathing the end plate 7 by the rib 9. The bubbles increase in the mixing rate as the rotational speed of the end plate 7 increases, and are supplied to the oil-repellent treatment unit 10 to actively form the air layer 12. 12 acts to hold. Furthermore, the viscous resistance of the lubricating oil is reduced by mixing bubbles in the lubricating oil.

  As described above, in the configuration described above, the lubricating oil attached to or about to adhere to the side surface of the end plate 7 is repelled by the oil repellent treatment unit 10, and dragging of the lubricating oil by the end plate 7 can be reduced. Further, since bubbles are mixed into the lubricating oil by the ribs 9 and the bubbles are positively supplied to the oil repellent treatment unit 10, the oil repellency and durability of the oil repellent treatment unit 10 can be improved. As a result, the stirring loss of the end plate 7 can be reduced.

  FIG. 5 shows the effect of reducing the stirring loss according to the present invention. The solid line in FIG. 5 shows the change in the output torque of the engine that drives the rotating member and the change in the rotational speed of the rotating member in the rotating member (end plate 7) provided with the oil repellent treatment portion 10 and the wing-shaped rib 9 described above. The correlation is shown. The broken line shows the correlation between the output torque of the engine and the change in the rotational speed when the above-described oil-repellent treatment portion 10 is applied to the end plate 7 having the rib 9 having the conventional shape. The dotted line shows the correlation between the output torque of the engine and the change in the rotational speed in the end plate 7 having a conventional shape that has not been subjected to the oil repellent treatment. As shown in FIG. 5, when the end plate 7 is provided with the oil repellent treatment portion 10 and the shape of the rib 9 is changed to increase the mixing rate of bubbles, the oil repellent performance of the oil repellent treatment portion 10 is improved. At the same time, the durability is improved and the stirring loss due to the drag of the lubricating oil can be reduced.

  That is, in the configuration described above, the air layer 12 is formed in the oil-repellent treatment unit 10 by supplying air bubbles to the oil-repellent treatment unit 10, so that the present invention is compared with the end plate 7 of the conventional configuration. In the end plate 7 to which is applied, adhesion of lubricating oil to the side surface is prevented or suppressed. In other words, shearing between the air layer 12 and the lubricating oil causes the adhesion of the lubricating oil to be prevented or suppressed, and the durability of the oil repellent treatment unit 10 can be improved. More specifically, the shearing of the lubricating oil by the end plate 7 is suppressed or reduced, that is, the shearing of the lubricating oil by the oil-repellent processing unit 10 coated with the fluororesin is suppressed or reduced. As a result, the oil-repellent processing unit 10 and the deterioration of the durability of the lubricating oil can be suppressed. Further, this can suppress the heat generation of the lubricating oil.

  FIG. 6 shows an example in which the configuration shown in FIG. 1 is improved. In the example shown here, the bubble presence rate on the side surface of the rotating member increases from the center of rotation to the outer peripheral edge, so the bubble rate in the vicinity of the center of rotation of the rotating member is increased. This is an example in which bubbles are uniformly supplied to the entire surface. More specifically, FIG. 11 schematically shows the arrangement of the fastening members 8 provided on the conventionally known end plate 7. In the configuration shown in FIG. A plurality of fastening members 8 are arranged between the inner peripheral edge r0 and the outer peripheral edge r2 of the end plate 7 that passes through (position indicated by r1 in FIG. 11).

  FIG. 6 schematically shows an example in which the arrangement of the fastening members is changed, and a plurality of fastening members 8 are alternately arranged on the inner peripheral edge r0 side and the outer peripheral edge r2 side of the end plate 7. . Each fastening member 8 is provided to protrude in the vertical direction of the side surface of the end plate 7. Accordingly, the plurality of fastening members 8 serve as bubble mixing means in the present invention, and the bubbles are mixed by scraping up the lubricating oil as the end plate 7 rotates. Further, the fine unevenness described above is formed on the side surface of the end plate 7, and an oil-repellent treatment in which a fluorine resin or the like is coated thereon is performed. In the configuration shown in FIG. The lubricating oil adhering to or about to adhere to the side surface 7 is repelled by the oil-repellent treatment unit 10. The oil repellent portion 10 is supplied with bubbles mixed in the lubricating oil by the plurality of fastening members 8 described above.

  FIG. 7 shows the mixing ratio of bubbles on the side surface of the end plate configured as shown in FIG. The solid line in FIG. 7 shows the mixing rate of bubbles by the end plate 7 having the configuration shown in FIG. 6, and the broken line shows the mixing rate of bubbles by the conventionally known end plate 7 shown in FIG. . As shown in FIG. 7, the end plate 7 of the conventional configuration has a high bubble mixing rate in the vicinity of a place where a plurality of fastening members 8 are arranged (a place indicated by reference numeral r1 in FIG. 11). However, in the vicinity of the inner peripheral edge r0 and the outer peripheral edge r2 of the end plate 7, the bubble mixing rate is relatively low. On the other hand, in the end plate 7 having the configuration shown in FIG. 6, a plurality of fastening members 8 are alternately provided on the inner peripheral edge r0 side and the outer peripheral edge r2 side of the end plate 7, thereby scooping up the lubricating oil. Since the bubbles are mixed, the bubble mixing rate can be improved uniformly over the entire side surface of the end plate 7.

  More specifically, since the fastening member 8 provided on the inner peripheral edge r0 side of the end plate 7 scoops up the lubricating oil and mixes bubbles, the end plate 7 of the conventional configuration has a bubble mixing (presence) rate. The mixing (presence) rate of bubbles on the relatively low inner peripheral edge r0 side can be improved. Therefore, by providing the plurality of fastening members 8 alternately on the inner peripheral edge r0 side and the outer peripheral edge r2 side of the end plate 7, air bubbles can be present over the entire side surface of the end plate 7.

  Further, as described above, the oil repellent treatment unit 10 is provided on the side surface of the end plate 7, bubbles are supplied to the oil repellent treatment unit 10, and the air layer 12 of the oil repellent treatment unit 10 is maintained. Therefore, the shearing action of the lubricating oil by the end plate 7 is suppressed or reduced. In other words, it becomes a shearing action between the air layer 12 and the lubricating oil, so that the oil repellency of the oil repellent portion 10 can be improved, and the durability of the oil repellent portion 10 and the lubricating oil can be suppressed from decreasing.

  FIG. 8 shows the reduction rate of the stirring loss in the radial direction of the end plate having the configuration shown in FIG. The solid line in FIG. 8 indicates the reduction rate (%) of the stirring loss in the radial direction of the end plate 7 having the configuration shown in FIG. 6, and the broken line is in the radial direction of the end plate 7 having the conventional configuration shown in FIG. The reduction rate (%) of stirring loss is shown. As shown in FIG. 8, the end plate 7 having the conventional configuration has the highest reduction rate (%) of the stirring loss in the vicinity of the place where the plurality of fastening members 8 are disposed (the place indicated by reference numeral r1 in FIG. 11). It is high. Further, the reduction rate (%) of the stirring loss on the outer peripheral edge r2 side is larger than that on the inner peripheral edge r0 side. That is, the effect of reducing the stirring loss is increased at a location where many bubbles are present.

  On the other hand, the end plate 7 having the configuration shown in FIG. 6 has a reduction rate (%) of the stirring loss on the outer peripheral edge r2 side relatively larger than that on the inner peripheral edge r0 side. Therefore, the reduction rate (%) of the stirring loss on the inner peripheral edge r0 side and the outer peripheral edge r2 side is lower than the reduction rate (%) of the stirring loss of the end plate 7 of the conventional configuration. It is high. Therefore, by disposing the fastening members 8 on the inner peripheral edge r0 side and the outer peripheral edge r2 side of the end plate 7, it is possible to improve the mixing rate of bubbles over the entire side surface of the end plate 7 and to distribute the bubbles uniformly. In addition, it is possible to improve the effect of reducing the stirring loss over the entire side surface of the end plate 7. As a result, the oil repellency of the oil repellent treatment part 10 can be improved, and the stirring loss due to the drag of the lubricating oil can be reduced. In addition, the durability of the oil repellent portion 10 can be improved.

  Next, an example in which the present invention is applied to a helical gear will be described. FIG. 12 schematically shows the conventional lubrication of the lubricating oil by a spur gear. The spur gear 13 has teeth 13a formed in parallel with the rotation center axis thereof, and bubbles are mixed into the lubricating oil as the lubricating oil is scraped up by the teeth 13a. Therefore, the air bubbles mixed in the lubricating oil are formed in parallel with the rotation center axis of the spur gear 13 because the teeth 13a for mixing the air bubbles in the lubricating oil are blown out to which side of the spur gear 13, or the direction in which the air bubbles are discharged. Is not fixed.

  FIG. 13 and FIG. 14 schematically show an example in which the present invention is applied to a helical gear. The helical gear 14 is a gear formed so that the teeth 14a are twisted with respect to the central axis by an angle θ2. Therefore, the meshing of the teeth between the driving gear and the driven gear is performed. However, it starts at one end in the width direction, the meshing location changes toward the other end, and changes from the tooth tip side to the tooth base side or from the tooth root side to the tooth tip side. In the example shown here, an oil repellent effect is formed on the side surface 14b of the gear on the side where the meshing of the teeth 14a of the two helical gears 14 (that is, the driving gear and the driven gear) that are relatively operated is released. In this example, the processing unit 10 is formed.

  More specifically, in the configuration shown in FIG. 13, the side surface of the helical gear 14 on the side that is released from meshing with the teeth 14a of the helical gear 14 that operates relatively (in FIG. The oil repellent treatment portion 10 is provided on the right side surface 14b of the gear 14. FIG. 14 shows a helical gear 14 which meshes with the helical gear 14 shown in FIG. 13 and operates relatively, and is released from meshing with the teeth 14a of the helical gear 14 shown in FIG. The oil repellent portion 10 is provided on the side 14b (the left side surface of the helical gear 14 in FIG. 14) 14b. Therefore, the tooth 14a of the helical gear 14 is the bubble mixing means in this invention. Further, the oil repellent treatment portion 10 is provided on the side surface 14b of the helical gear 14 on the side where the teeth 14a of the helical gear 14 are released from meshing, and the above-described fine irregularities are formed thereon. In addition, an oil repellent treatment coated with a fluorine resin or the like is performed. Therefore, also in the configuration shown in FIGS. 13 and 14, the lubricating oil adhering to or about to adhere to the side surface 14 b of the helical gear 14 is repelled by the oil-repellent treatment portion 10. The oil repellent portion 10 is supplied with air bubbles mixed in the lubricating oil by the teeth 14a.

  FIG. 15 schematically shows the distribution of bubbles when bubbles are mixed into the lubricating oil by the spur gear shown in FIG. As shown in FIG. 15, the spur gear 13 has teeth 13a formed in parallel to the central axis, that is, the teeth 13a are not twisted with respect to the central axis, so that air bubbles mixed in by the teeth 13a are mixed. Are present in the circumferential direction of the spur gear 13 (that is, along the teeth 13a). In other words, since the teeth 13a are formed parallel to the central axis, bubbles mixed in the lubricating oil do not exist on either side of the spur gear 13 in a biased manner.

  FIG. 16 schematically shows the distribution of bubbles when bubbles are mixed into the lubricating oil by the helical gear shown in FIG. FIG. 17 schematically shows the distribution of bubbles when bubbles are mixed into the lubricating oil by the helical gear shown in FIG. As shown in FIGS. 16 and 17, and as described above, the tooth 14a of the helical gear 14 is formed by twisting the tooth 14a with respect to its central axis by an angle θ2. The mixing (presence) rate of the bubbles mixed into the lubricating oil by the teeth 14a is increased on the side surface 14b on the side released from the meshing with the teeth 14a of the other helical gear 14 that operates relatively. In other words, by adjusting the twist angle θ2 of the tooth 14a, the blowing direction of the bubbles mixed by the tooth 14a can be changed. In other words, the bubble concentration in the vicinity of the oil repellent portion 10 can be adjusted by adjusting the twist angle θ2 of the teeth 14a. Further, since the bubbles are mixed by the teeth 14a, the bubble mixing rate (bubble density) can be increased as the rotational speed of the helical gear 14 increases.

  In this way, by providing the oil repellent treatment portion 10 on the side surface 14b on the side where the meshing of the teeth 14a of the helical gear 14 is released, it adheres to or tends to adhere to the side surface 14b of the helical gear 14. Lubricating oil is repelled by the oil repellent treatment unit 10 and bubbles mixed by the bubbles 14a of the helical gear 14 are positively supplied to the oil repellent treatment unit 10. The oil repellency and durability of the oil repellent portion 10 can be improved. Moreover, the viscous resistance is lowered by the bubbles mixed in the lubricating oil. As a result, in the configuration described above, drag of the lubricating oil by the helical gear 14 can be reduced and stirring loss can be reduced. Moreover, since it is only necessary to perform the oil repellent treatment only on the side where the bubbles are supplied (that is, the side surface 14b), the cost can be reduced.

  Next, an example in which the present invention is applied to a rotating member which is entirely immersed in lubricating oil will be described. In the example shown here, lubricating oil is filled in a so-called test box, and a rotating disk subjected to oil repellent treatment is immersed in the lubricating oil, and bubbles are forcibly supplied to the lubricating oil. This is an example configured as described above. FIG. 18 shows the effect of reducing the stirring loss when the present invention is applied to a rotating member which is entirely immersed in lubricating oil. The solid line in FIG. 18 shows the output torque and rotation of the engine that drives the rotating disk when bubbles are forcibly mixed in the lubricating oil that immerses the rotating disk that has been subjected to the oil repellent treatment inside the test box. The correlation with the change of the rotation speed of the disk is shown. The broken line shows the correlation between the output torque and the rotational speed of the rotating disk subjected only to the oil repellent treatment, and the dotted line shows the correlation between the output torque and the rotational speed of the untreated rotating disk.

  As shown in FIG. 18, the oil-repellent rotating disc (rotating member) can reduce the drag of the lubricating oil due to its oil-repellent performance compared to the untreated rotating disc. , Stirring loss can be reduced. Then, when bubbles are mixed (supplied) into the lubricating oil immersed in the rotating disc subjected to the oil repellent treatment, the lubricating oil is more dragged than in the case where bubbles are not mixed in the lubricating oil. As a result, stirring loss can be further reduced. This is because air bubbles 12 are formed in the oil-repellent treatment unit 10 by mixing bubbles, shearing between the air layer 12 and the lubricating oil occurs, and the viscosity of the lubricating oil is determined by mixing bubbles in the lubricating oil. This is because the resistance decreases. In FIG. 18, the rotating disk to which the present invention was applied was able to reduce the stirring loss by about 25% compared to the untreated rotating disk.

  Thus, by supplying bubbles to the oil-repellent treatment unit 10 provided on the rotating member, the stirring loss of the rotating member can be reduced. As described above, the air layer 12 is formed between the oil repellent treatment unit 10 and the lubricating oil by positively supplying the bubbles to the oil repellent treatment unit 10, and the lubricating oil is retained. This is because a shearing action between the air layer 12 and the air layer 12 occurs. Further, the viscosity resistance of the lubricating oil can be reduced by mixing bubbles in the lubricating oil. Furthermore, even if the rotating member subjected to the oil repellent treatment rotates at a high speed, the oil repellent performance can be improved. That is, even when the rotating member rotates at a high speed to generate centrifugal hydraulic pressure, air bubbles are supplied to the oil repellent treatment unit 10, so that an air layer 12 is formed between the oil repellent treatment unit 10 and the lubricating oil. , Also hold. As a result, it is possible to improve the durability of the oil repellent portion 10 even in a region where the rotating member rotates at a high speed.

  Therefore, according to the present invention, the oil repellent treatment part 10 is provided on the side surface of the rotating member, and bubbles are supplied to the oil repellent treating part 10 by the bubble mixing means, whereby the stirring loss of the rotating member can be reduced and The oil repellency and durability of the oil treatment unit 10 can be improved.

  DESCRIPTION OF SYMBOLS 10 ... Rotating member (end plate), 11 ... Fastening member, 9 ... Rib, 10 ... Oil-repellent treatment part, 14 ... Helical gear, 14a ... Teeth.

Claims (4)

At least a part of the rotating member is bathed in a lubricating oil that lubricates the rotating member, and at least a part of the rotating member is lubricated with an oil-repellent treatment part that repels the lubricating oil. In structure
On the side surface of the rotating member, an uneven structure for roughening the side surface is formed, and the oil repellent treatment portion coated with a low surface tension treatment agent is provided,
A lubrication structure for a rotating member, further comprising bubble mixing means for mixing bubbles in the lubricating oil on a side surface of the rotating member on which the oil repellent treatment portion is formed. 2. The lubricating structure for a rotating member according to claim 1, wherein the bubble mixing means includes a wing-shaped rib provided on a side surface of the rotating member and protruding in a rotating direction of the rotating member. The bubble mixing means is provided on a side surface of the rotating member, and includes a plurality of fastening members that fasten the rotating member to a member that rotates integrally with the rotating member,
2. The plurality of fastening members are provided in the vicinity of the rotation center of the rotating member, and the other plurality of fastening members are provided in the vicinity of an outer peripheral edge of the rotating member. Or the lubricating structure of the rotating member of 2. At least a part of the rotating member is bathed in a lubricating oil that lubricates the rotating member, and at least a part of the rotating member is lubricated with an oil-repellent treatment part that repels the lubricating oil. In structure
The rotating member includes a helical gear,
An uneven structure for roughening the side surface is formed on the side surface of the helical gear on the side where the tooth is released from meshing with another helical gear tooth, and a low surface tension treatment agent A lubrication structure for a rotating member, characterized in that the oil-repellent treatment part coated with is provided.

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