JP2010156399A - Toroidal type continuously variable transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize a structure reducing a torque loss of a thrust rolling bearing by reducing agitation resistance of lubrication oil as well as efficiently feeding the lubrication oil into respective pockets. <P>SOLUTION: Convex parts 24, 24 expanding to the axial direction of a main element 11a are formed at in-between parts between adjacent pockets in the circumferential direction, in a diameter direction intermediate part of both inside/outside surfaces of the main element 11a composing a retainer 10a. Compared with a case in which these convex parts 24, 24 are not formed in these in-between parts, therefore, volumes of spaces 23a, 23a between rolling bodies formed between these in-between parts and inner/outer ring tracks 6, 8 are decreased. As a result, the above problem is solved. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The toroidal continuously variable transmission according to the present invention is used as a transmission for an automobile or as a transmission for adjusting the operating speed of various industrial machines such as a pump.

  Toroidal continuously variable transmissions used as automatic transmissions for automobiles are described in many publications such as Patent Document 1, Non-Patent Documents 1 and 2, and are partly implemented and well known. . For example, as shown in FIG. 19, there are a plurality of such toroidal-type continuously variable transmissions between the input disks 1 and 1 and the output disks 2 and 2 each having a toroidal curved surface in the axial direction facing each other. The power rollers 3 and 3 are sandwiched. During operation, the rotation of the input disks 1, 1 is transmitted to the output disks 2, 2 via these power rollers 3, 3. The power rollers 3 and 3 are rotatably supported by trunnions 4 and 4, respectively. The trunnions 4 and 4 are pivots (twisted with respect to the central axes of the disks 1 and 2). Oscillating displacement centered around (not shown) is supported freely. When changing the gear ratio between the disks 1 and 2, the trunnions 4 and 4 are displaced in the axial direction of the pivot by, for example, a hydraulic actuator (not shown).

  As a result, the direction of the tangential force acting on the rolling contact portion (traction portion) between the peripheral surfaces of the power rollers 3 and 3 and the inner surfaces of the input and output disks 1 and 2 changes (rolling contact). Side slip occurs in the part). As the force changes, the trunnions 4 and 4 swing around the pivot, and the peripheral surfaces of the power rollers 3 and 3 and the inner surfaces of the input and output disks 1 and 2 are used. The contact position changes. The peripheral surfaces of the power rollers 3 and 3 are brought into rolling contact with the radially outward portion of the inner surface of the input discs 1 and 1 and the radially inward portion of the inner surfaces of the output discs 2 and 2. For example, the gear ratio between the two disks 1 and 2 is increased. On the other hand, the peripheral surfaces of the power rollers 3 and 3 are arranged in a radially inward portion of the inner surface of the input disks 1 and 1 and a radially outward portion of the inner surfaces of the output disks 2 and 2. , The gear ratio between the two disks 1 and 2 is reduced.

  During operation of the toroidal type continuously variable transmission as described above, the power rollers 3 and 3 rotate at high speed while receiving a large thrust load from the disks 1 and 2. For this purpose, thrust ball bearings 5 and 5 are provided between the power rollers 3 and 3 and the trunnions 4 and 4, respectively. It is possible to support the thrust load applied to As shown in detail in FIG. 20, these thrust ball bearings 5, 5 are provided with an inner ring raceway 6 formed on the outer surface (lower surface in FIG. 20) of each power roller 3 and the inner surface of each trunnion 4. The outer ring raceway 8 formed on the inner side surface of the outer ring 7 installed on (the upper surface of FIG. 20), and each of the rolling rings provided between the inner ring raceway 6 and the outer ring raceway 8 is a rolling element. It consists of balls 9 and 9 and a cage 10 that holds these balls 9 and 9.

  The cage 10 includes a ring-shaped main body 11 having a uniform wall thickness in the diameter direction, and pockets 12 and 12 provided intermittently at a plurality of positions in the circumferential direction of the main body 11. In the case of the illustrated structure, the inner surfaces of these pockets 12 and 12 are constituted by cylindrical surfaces that open on both side surfaces of the main body 11 in the axial direction. And in each of these pockets 12 and 12, each said balls 9 and 9 are held so that rolling is possible. In the case of the structure shown in FIG. 20, unlike the structure shown in FIG. 19, the outer ring 7 is supported by the support shaft 13 for rotatably supporting the power rollers 3, and the powers of these. The roller 3 is integrally formed with each trunnion 4 and a pivot shaft 14 for supporting the input and output disks 1 and 2 in a state in which displacement in the axial direction is allowed. Further, the shape of the power roller 3 is also different from the structure of FIG. However, these differences are not important in relation to the present invention.

  By the way, the thrust ball bearing 5 as described above rotates at high speed while supporting the thrust load applied to each of the power rollers 3 when the toroidal type continuously variable transmission is operated. For this reason, it is necessary to supply a sufficient amount of lubricating oil to each thrust ball bearing 5 during operation, and to lubricate and cool each part. Therefore, conventionally, as shown in FIG. 20, the lubricating oil is fed into the oil supply hole 15 formed inside the pivot shaft 14, and the thrust ball bearing 5 is connected through the branch hole 16 branched from the oil supply hole 15. Lubricating oil is supplied (discharged) to the inner diameter side. The lubricating oil supplied in this way is caused by centrifugal force accompanying the rotation of each power roller 3 (and cage 10), and both axial side surfaces (both inner and outer sides) of the cage 10 and each power roller 3 The gaps between the outer surface of the outer ring and the inner surface of each outer ring 7 flow toward the outer diameter side. And each part, such as a rolling contact part, is lubricated and cooled simultaneously. This prevents a part of the thrust ball bearing 5 from being significantly worn or seized.

  Conventionally, in order to efficiently feed the lubricating oil supplied to the thrust ball bearing 5 into the pockets 12 and 12, as shown in FIGS. It is known that the concave grooves 17 and 17 are formed on the side surface in the diameter direction of the main body 11 so as to cross the pockets 12 and 12 (see Patent Document 2). According to such a configuration, a sufficient amount of lubricating oil can be supplied into the pockets 12 and 12 even when the cage 10 is displaced in the axial direction. For example, in the case of the structure shown in FIG. 20, the inner peripheral portion 18 and the outer peripheral portion 19 of the main body 11 and the inner diameter of the inner surface of each outer ring 7 that faces both the peripheral portions 18 and 19. Side and outer diameter side shoulder portions 20a and 20b (when the concave grooves 17 and 17 are provided on the inner side surface of the main body 11, the inner diameter side and outer diameter side shoulder portions 21a and 21b of the outer surface of the power roller 3) ), A sufficient amount of lubricating oil can be supplied into the pockets 12 and 12 through the concave grooves 17 and 17.

  However, when a cage having a conventional structure including the cage 10 having the above-described configuration is used, there arises a problem that the agitation resistance of the lubricating oil is increased during operation of the thrust rolling bearing. This reason will be described using the cage 10 shown in FIGS. 20 and 21. FIG. As described above, since the thickness of the main body 11 constituting the cage 10 is constant over the diameter direction, the pockets 12 adjacent to each other in the circumferential direction are formed on both side surfaces of the main body 11 in the axial direction. Flat surface portions 22 and 22 are present between the twelve portions. Therefore, between these flat surface portions 22 and 22 and the inner ring raceway 6 and the outer ring raceway 8 facing the respective flat surface portions 22 and 22, the rolling surfaces of the balls 9 and 9 adjacent in the circumferential direction ( The space between the rolling elements 23 and 23 is formed in which both sides in the circumferential direction are partitioned by the portion exposed from the cage 10) and each has a certain large volume.

  And in each said rolling element space 23 and 23, a part of lubricating oil which overflowed from each said groove 17 and 17 and parts other than these each groove 17 and 17 (circumferential direction adjoins). Lubricating oil and the like flowing in from the concave grooves 17 and 17) flows in. For this reason, the spaces 23 and 23 between the rolling elements are in a state where a certain amount of lubricating oil is accumulated. Therefore, during operation of the toroidal continuously variable transmission, the portion of the rolling surface of each of the balls 9, 9 exposed from the cage 10 is the lubricating oil that has accumulated in the spaces 23, 23 between the rolling elements. It will collide with (slurry the lubricating oil). As a result, there arises a problem that the rotational resistance (dynamic torque) of the power roller 3 is increased based on the stirring resistance of the lubricating oil.

  As inventions that can reduce the stirring resistance of the lubricating oil as described above, there are inventions described in Patent Documents 3 and 4, for example. In the case of the invention described in Patent Document 3 among these, among the axial side surfaces of the main body constituting the cage, the inner peripheral edge and the outer peripheral edge of the main body are located between the adjacent pockets in the circumferential direction. Spiral grooves that communicate with each other are formed. The spiral groove allows the lubricating oil flowing into the space between the rolling elements to be discharged toward the inner diameter side of the cage. On the other hand, in the case of the invention described in Patent Document 4, a wall portion for preventing the flow of lubricating oil is formed in a portion of the main inner peripheral edge portion that is separated from each pocket in the circumferential direction. ing. These wall portions prevent the lubricating oil from flowing into the space between the rolling elements. Any of the inventions described in Patent Documents 3 and 4 can reduce the amount of lubricating oil present in the space between the rolling elements, which is advantageous in reducing the stirring resistance.

However, in the case of the invention described in Patent Document 3, when the amount of lubricating oil supplied to the thrust ball bearing is increased, the amount of lubricating oil discharged from the spaces between the rolling elements by the spiral grooves is larger than these. The amount of lubricating oil flowing into the spaces between the rolling elements increases, and as a result, a collective amount of lubricating oil stays in the spaces between the rolling elements. Also in the case of the invention described in Patent Document 4, the amount of lubricating oil flowing into the spaces between the rolling elements increases as the amount of lubricating oil supplied to the thrust ball bearing increases. In addition, when the toroidal continuously variable transmission is operated, the cage rotates at a high speed, so that a part of the lubricating oil flowing into the pockets may flow out toward the spaces between the rolling elements. As described above, in any of the inventions described in Patent Documents 3 and 4, since the volume of the space between the rolling elements is not reduced, the amount of lubricating oil supplied to the thrust ball bearing is increased. In such a case, the effect of reducing the stirring resistance cannot be sufficiently obtained.
As other prior art documents related to the present invention, there are inventions described in Patent Documents 5 to 8, but none of them can solve the above-mentioned problems.

JP 2001-317601 A Japanese Utility Model Publication No. 7-35847 JP 2004-340268 A JP 2007-107625 A JP-A-10-246301 JP 2004-76912 A JP 2001-254792 A JP 2006-307900 A Motoo Aoyama, "Bessed Best Car Red Badge Series 245 / A book that understands the latest mechanics of cars", Sanyusha Co., Ltd./Kodansha Co., Ltd., December 20, 2001, p. 92-93 Hirohisa Tanaka, “Toroidal CVT”, Corona Inc., July 13, 2000

  In view of the circumstances as described above, the present invention reduces the agitation resistance of the lubricating oil, reduces the torque loss of the thrust rolling bearing, and can efficiently feed the lubricating oil into each pocket. It was invented to realize a continuously variable transmission. Furthermore, it is intended to reduce the shear resistance of the lubricating oil and to prevent interference between the inner surface of each pocket and the rolling elements (balls) as necessary.

The toroidal type continuously variable transmission of the present invention has an input disk, an output disk, a plurality of trunnions, and a plurality of support shafts, for example, in the same manner as the conventional toroidal type continuously variable transmission shown in FIG. And a plurality of power rollers and a plurality of sets of thrust rolling bearings.
Of these, the input disk and the output disk are supported concentrically so as to be freely rotatable relative to each other.
Each trunnion is provided between the two discs with respect to the axial direction of the two discs, is concentric with each other at both ends, and is twisted with respect to the central axis of the two discs. Oscillating displacement around the pivot axis is free.
Each of the support shafts is provided for each of the trunnions in a state protruding from the inner surface of each of the trunnions.
Each power roller is sandwiched between the two disks while being rotatably supported around each support shaft.
Each thrust rolling bearing is provided between the outer surface of each power roller and the inner surface of each trunnion.
Each thrust rolling bearing includes an inner ring raceway formed on the outer side surface of each power roller, an outer ring raceway formed on the inner side surface of the outer ring installed on the inner side surface of each trunnion, and the inner ring raceways. It comprises a plurality of rolling elements provided between the raceway and the outer ring raceway so as to be freely rollable, and a cage for holding the rolling elements.

In particular, in the toroidal type continuously variable transmission according to the present invention, the cage is formed intermittently at an annular main body and at a plurality of locations in the circumferential direction of the main body. And a pocket for holding the roll freely.
Of the diametrically intermediate portions of both sides of the main body in the axial direction (both inner and outer side surfaces), between the pockets adjacent to each other in the circumferential direction, the portion between each of the inner ring track and the outer ring track Protrusions that block a part of the space existing between them (space between rolling elements) are provided.
In addition, as a ratio of closing each space by these convex portions, as in the case of the conventional structure shown in FIG. When the volume is 100%, it is preferable to block at least 70%, preferably about 90%.

Further, when implementing the toroidal type continuously variable transmission according to the present invention, preferably, as in the invention according to claim 2, for example, both side surfaces of the main body in the axial direction, the outer surfaces of the power rollers, and the outer rings. The sum of the gaps formed between the inner peripheral surfaces of the main body and the inner peripheral surface (total thickness in the axial direction) is made smaller at the inner peripheral edge portion than at the outer peripheral edge portion of the main body.
Further, when the invention according to claim 2 is carried out, it is preferable that the sum of the gaps formed between each of the convex portions and the inner ring raceway and the outer ring raceway is defined as the gap in the inner peripheral edge portion. It is larger than the sum (total axial thickness) and smaller than the sum of the gaps at the outer peripheral edge (total axial thickness).

Further, when implementing the toroidal type continuously variable transmission according to the present invention, preferably, as in the invention according to claim 3, the pockets of the pockets are formed by both side surfaces of the convex portions in the circumferential direction of the main body. A part of the inner surface is formed, and the inner surface of each pocket is formed by smoothly connecting the inner spherical surface portion and the outer cylindrical surface portion at the intermediate portion with respect to the diameter direction of the main body. Further, these cylindrical surface portions are communicated (opened) to the outer peripheral surface of the main body.
Further, when the invention according to claim 3 as described above is carried out, preferably, as in the invention according to claim 4, the pitch circle diameter of the spherical portion constituting the inner surface of each pocket is set to each rolling element. It should be smaller than the pitch circle diameter of the ball.
In carrying out the inventions according to claims 3 and 4, balls are used as rolling elements constituting the thrust rolling bearing.

Further, when implementing the toroidal type continuously variable transmission according to the present invention, preferably, as in the invention according to claim 5, for example, the bus bar shape of each convex portion is a single arc, and the bus bar of each convex portion is The curvature radius of the shape is made smaller than the curvature radii of the inner ring raceway and the outer ring raceway.
Alternatively, as in the invention according to claim 6, a flat surface parallel to a virtual plane orthogonal to the central axis of the main body is provided at the tip of each convex portion in the axial direction of the main body.

Further, when implementing the toroidal type continuously variable transmission according to the present invention, preferably, as in the invention according to claim 7, for example, the inner peripheral edge of the main body and the pockets communicate with each other on the side surface in the axial direction of the main body. A lubricating oil flow path is provided.
When carrying out the invention according to claim 7, it is also possible to provide a lubricating oil flow path that communicates the pockets with the outer peripheral edge of the main body. That is, as in the case of the conventional structure shown in FIGS. 20 and 21, the lubricating oil flow path can be provided in a state crossing the pockets.

According to the toroidal continuously variable transmission of the present invention having the above-described configuration, the stirring resistance of the lubricating oil can be reduced, the torque loss of the thrust rolling bearing can be reduced, and the lubricating oil can be efficiently injected into each pocket. You can send it in.
That is, in the case of the present invention, among the diametrically intermediate portions of both axial side surfaces of the main body constituting the cage, between the pockets adjacent to each other in the circumferential direction and the inner ring track and the outer ring track. The volume of the space formed in the above can be made smaller than in the case where no convex portion is provided at each of these portions (simply a flat surface). For this reason, the amount of lubricating oil that can stay in each space can be reduced. Therefore, even when the amount of lubricating oil supplied to the thrust rolling bearing increases, the amount of lubricating oil staying in the spaces can be reduced. Further, it is possible to prevent the lubricating oil flowing into the pockets from flowing into the spaces. As a result, during the operation of the thrust rolling bearing, the agitation resistance of the lubricating oil can be reduced when the rolling elements cross the spaces, and the torque loss (rotational resistance) of the thrust rolling bearing can be reduced. Furthermore, as the amount of lubricating oil that flows into each of these spaces can be suppressed to a low level, the lubricating oil is supplied into the pockets to lubricate the rolling contact surfaces of the rolling elements with the outer ring raceway and the inner ring raceway. It is also possible to increase the amount of lubricating oil provided to.

  Further, according to the invention according to claim 2, when the cage is displaced in the axial direction, the inner peripheral edge portion which is a portion having a short distance from the rotation center (small rotation radius) among the main bodies, The contact surface (the outer surface of the power roller or the inner surface of the outer ring) can be slidably contacted or closely opposed. In other words, it is possible to prevent the outer peripheral edge portion of the cage from being in sliding contact with or in close proximity to the mating surface. For this reason, the loss torque of the thrust rolling bearing and the shearing resistance of the lubricating oil can be reduced as compared with the case where the outer peripheral edge portions are in sliding contact or close to each other. Further, since a large gap can be secured at the outer peripheral edge of the main body, the lubricating oil flowing into the pockets can be efficiently discharged to the outside.

  According to the invention of claim 3, compared to the case where the inner surface of each pocket is constituted by a cylindrical surface opening on both sides in the axial direction of the main body (see FIG. 20), the circle of each convex portion. Both circumferential portions can be enlarged to the vicinity of the rolling surfaces of the balls held in the pockets. For this reason, the volume of each said space can be made smaller, and the stirring resistance of lubricating oil can further be reduced. Moreover, since the cylindrical surface part which comprises a part of inner surface of each said pocket is connected with the said outer peripheral surface, the lubricating oil supplied in these each pocket can also be discharged | emitted efficiently outside. . Furthermore, since the positioning of the cage in the axial direction can be regulated by so-called ball guidance, it is possible to effectively prevent the axial side surface of the cage (main body) and the mating surface from interfering (strongly rubbing).

  According to the invention of claim 4, among the inner surfaces of the respective pockets, the portion near the inner end of the main body in the diameter direction interferes with the rolling surfaces of the balls held in the respective pockets. Can be prevented from rubbing (strongly rubbing). For this reason, it is possible to prevent an increase in torque loss of the thrust rolling bearing.

According to the fifth aspect of the present invention, when a ball is used as each of the rolling elements and the cross-sectional shapes of the inner ring raceway and the outer ring raceway are arcuate, the volume of each space is effectively reduced. Can be small. In addition, it is possible to make it difficult for the convex portions to contact the inner ring track and the outer ring track.
According to the invention of claim 6, the height of each convex portion can be easily managed, and depending on the shape of each convex portion, when the cage is displaced in the diameter direction, each convex portion can be controlled. It is also possible to prevent the portion from interfering with the inner ring raceway and the outer ring raceway.

  Furthermore, according to the invention which concerns on Claim 7, while being able to send lubricating oil into each said pocket efficiently, the amount of lubricating oil which flows in into each said space can be restrained small.

[First example of embodiment of the present invention]
FIGS. 1-7 has shown the 1st example of embodiment of this invention corresponding to Claim 1,5,7. The feature of this example is that, by devising the shape of the portion between the pockets 12 adjacent to each other in the circumferential direction among the axially opposite side surfaces of the main body 11a constituting the cage 10a, The volume of the space formed between the inner ring raceway 6 and the outer ring raceway 8 is reduced, and the amount of lubricating oil staying in these spaces is reduced. Since the structure and operation of other parts are the same as those of the conventional structure shown in FIGS. 19 to 21 described above, overlapping illustrations and explanations are omitted or simplified, and the following description will focus on the characteristic parts of this example.

  The cage 10a incorporated in the thrust ball bearing 5a of this example is made of a metal material such as a copper alloy such as copper or brass (high strength brass), an iron alloy such as structural carbon steel, or a synthetic resin such as polyamide. As shown in FIG. 4, it is made of an annular main body 11a and pockets 12 and 12 provided intermittently at a plurality of circumferential positions of the main body 11a. The surface is provided with concave grooves 17 and 17 that serve as lubricating oil passages in a state of crossing the pockets 12 and 12 in the diameter direction of the main body 11a. In the case of this example as well, the inner surfaces of the pockets 12 and 12 are constituted by cylindrical surfaces that open on both side surfaces in the axial direction of the main body 11a, as in the case of the conventional structure shown in FIGS. is doing.

  In particular, in the case of this example, the pockets adjacent in the circumferential direction in the diametrically intermediate portion (the portion sandwiched between the inner peripheral edge portion 18 and the outer peripheral edge portion 19) on both axial sides of the main body 11a. Protrusions 24 and 24 bulging in the axial direction of the main body 11a are respectively provided between the portions 12 and 12. Each of the convex portions 24, 24 has a circumferential side surface thereof as a concave surface having a partial cylindrical surface, and is continuous with the inner surfaces of the pockets 12, 12. Each of the convex portions 24, 24 has an outer surface shape along each track groove of the inner ring raceway 6 formed on the outer side surface of the power roller 3 and the outer ring raceway 8 formed on the inner side surface of the outer ring 7. Most of them are inserted inside each of the track grooves.

For this reason, in the case of this example, the bus bar shape of each of the convex portions 24 and 24 is a single arc, and the radius of curvature r ₂₄ of the bus bar shape of each of the convex portions 24 and _{24 is set} to the inner ring raceway 6. than the radius of curvature r ₈ generatrix shape of radius of curvature r ₆ and the outer ring raceway 8 of the bus configuration, it is smaller by a gap t minutes _{(r 24 + t = r 6} = r 8). Further, the pitch circle diameters of the convex portions 24 and 24 are made to coincide with the pitch circle diameters of the balls 9 and 9 provided between the inner ring raceway 6 and the outer ring raceway 8. As a result, in the state where the cage 10a is positioned at the center in the axial direction between the outer side surface of the power roller 3 and the inner side surface of the outer ring 7, the tip surfaces of the convex portions 24, 24 and the inner ring The track 6 and the outer ring track 8 are arranged so as to face each other through a certain gap t in the width direction of the tracks 6 and 8.

  In the case of this example, most of the convex portions 24 and 24 are mounted in a state where the cage 10a is assembled between the outer surface of the power roller 3 and the inner surface of the outer ring 7. The size of the gap t (the amount of protrusion of the convex portions 24, 24) is restricted so that the inner ring raceway 6 and the outer ring raceway 8 can enter inside the raceway grooves. Specifically, the size of the gap t is set such that the distance D between the tip portions of the pair of convex portions 24, 24 provided on both axial sides of the main body 11 a is the inner ring track 6 and the outer ring track 8. Or about 80 to 90% of the distance L between the groove bottoms (≈the diameters of the balls 9, 9), or, among the protrusions 24, 24, The cross-sectional area of the portion that has entered the inside is regulated so as to occupy about 70 to 90% of the cross-sectional area of each track groove.

  However, the size of the gap t is the same as the gap between the inner peripheral edge portion 18 of the main body 11a and the mating surface (the inner diameter side shoulder portion 21a of the power roller 3 and the inner diameter side shoulder portion 20a of the outer ring 7). The gap between the peripheral edge portion 19 and the mating surface (the outer diameter side shoulder portion 21b of the power roller 3 and the outer diameter side shoulder portion 20b of the outer ring 7) is made larger than at least one of the gaps. Thereby, when the cage 10a is displaced in the axial direction, the convex portions 24, 24 are prevented from interfering with (rub against) the inner ring raceway 6 and the outer ring raceway 8. Also, the size of the gap t is somewhat large from the viewpoint of suppressing the shearing resistance of the lubricating oil flowing between the convex portions 24, 24 and the inner ring raceway 6 and the outer ring raceway 8 to a low level. Secure.

  In any case, in the case of the present example, the shape as described above is formed in the portion between the circumferentially adjacent pockets 12 and 12 in the diametrically intermediate portion on both axial sides of the main body 11a. By providing the convex portions 24 and 24 having the above, the volume of the inter-rolling member spaces 23a and 23a formed between the convex portions 24 and 24 and the inner ring raceway 6 and the outer ring raceway 8 is reduced. Compared to the volume of the inter-roller spaces 23 and 23 in the case where the convex portions 24 and 24 are not provided (in the case of simply flat surfaces, refer to FIG. 20), the volume is sufficient (at least 30%, preferably about 10%). Can be small. Therefore, the amount of lubricating oil that can stay in the rolling element spaces 23a and 23a can be reduced. Therefore, even when the amount of lubricating oil supplied to the inner diameter side of the thrust ball bearing 5a increases, the amount of lubricating oil flowing into (retaining) the rolling element spaces 23a, 23a can be suppressed to a small amount. In addition, it is possible to prevent the lubricating oil flowing into the pockets 12 and 12 from flowing into the spaces between the rolling elements 23a and 23a. Further, in the case of this example, the lubricating oil supplied to the inner diameter side of the thrust ball bearing 5a can be fed into the pockets 12 and 12 through the concave grooves 17 and 17, respectively. The amount of lubricating oil flowing into the space between moving bodies 23a, 23a can be reduced. As a result, during the operation of the thrust ball bearing 5a, the stirring resistance of the lubricating oil when the balls 9, 9 cross the rolling element spaces 23a, 23a is reduced, so that the thrust ball bearing 5a Torque loss (rotational resistance) can be reduced.

  Further, as the amount of lubricating oil flowing into the spaces between the rolling elements 23a, 23a is reduced, the lubricant is supplied into the pockets 12, 12, and the rolling surfaces of the balls 9, 9 and It is also possible to increase the amount of lubricating oil used for lubricating the rolling contact portion between the inner ring raceway 6 and the outer ring raceway 8. Thus, in the case of this example, since a sufficient amount of lubricating oil can be efficiently supplied into the pockets 12 and 12 holding the balls 9 and 9, the cooling efficiency is comparable to that of the conventional structure. Can be obtained with a smaller amount of lubricating oil (lubricating oil supplied to the inner diameter side of the thrust ball bearing 5a) than in the case of the conventional structure. Alternatively, further cooling efficiency can be obtained by supplying the same amount of lubricating oil as in the conventional structure.

  In the case of manufacturing the cage 10a of this example, the main body 11a and the projections 24 and 24 can be formed integrally, or can be joined after being made separately. That is, when the cage 10a is made of a metal material such as a copper-based alloy or an iron-based alloy, an annular shape having a thickness dimension including the thickness dimension (protrusion amount) of each of the protrusions 24, 24 is used. After forming the main body, the pockets 12 and 12 can be formed and the convex portions 24 and 24 can be formed by cutting or grinding. Even when the cage 10a is made of a synthetic resin, the main body 11a and the convex portions 24 and 24 can be integrally formed by injection molding. Further, as shown in FIG. 7, after the main body 11 having a uniform wall thickness in the diametrical direction and the convex portions 24 and 24 are separately formed, the convex portions 24 and 24 are formed on the main body. 11, the cage 10 a is joined by welding, brazing, or bonding with an adhesive to a portion between the pockets 12, 12 adjacent to each other in the circumferential direction (flat surface portions 22, 22). It can also be.

[Second example of the embodiment of the present invention]
FIGS. 8-11 has shown the 2nd example of embodiment of this invention corresponding to Claim 1,3,5,7. The feature of this example is that the inner surface shape of each pocket 12a, 12a constituting the cage 10b is devised. Specifically, among the inner surfaces of these pockets 12a, 12a, both side portions in the axial direction of the main body 11b are constituted by the circumferential side surfaces of the respective convex portions 24a, 24a, and the pockets 12a, 12a The inner surface has a configuration in which the inner spherical surface portions 25 and 25 and the outer cylindrical surface portions 26 and 26 are smoothly connected at the intermediate portion with respect to the diameter direction of the main body 11b.

  Each of the spherical surface portions 25, 25 is a partial spherical concave surface having a single center, and the radius of curvature of each of the spherical portions 25, 25 is larger than the radius of curvature of the rolling surface of each ball 9, 9 held in each of the pockets 12a, 12a. Slightly larger than the pocket gap. Further, the centers of curvature of the spherical portions 25, 25 are made to coincide with the centers of the balls 9, 9 to be held in the pockets 12a, 12a. On the other hand, each of the cylindrical surface portions 26, 26 exists on a single cylindrical surface centered on an axis existing in the radial direction of the cage 10b, and the respective curvature radii thereof are the spherical surface portions 25, 25. It is the same as the radius of curvature.

  Further, in the case of this example, the pockets 12a and 12a are connected to the outer diameter side of the cage 10b by communicating (opening) the cylindrical surface portions 26 and 26 with the outer peripheral surface of the main body 11b. Open. Therefore, in the case of this example, the concave grooves 17 and 17 for guiding the lubricating oil into the pockets 12a and 12a are provided between the inner peripheral edge of the main body 11a and the pockets 12a and 12a (inner peripheral edge). Only part 18) is formed. In the case of this example having such a configuration, the balls 9 and 9 are assembled (inserted) into the pockets 12a and 12a from the outer diameter side of the cage 10b.

  In the case of this example having the above-described configuration, both the circumferential portions of the convex portions 24a and 24a are connected to the balls 9 and 9 as compared with the case of the first example of the embodiment described above. Can be enlarged to the vicinity of the rolling surface (position where the pocket gap is left). In other words, in the case of the structure of the first example, the circumferential side surfaces of the convex portions 24 and 24 are partially cylindrical concave surfaces, and therefore, between the rolling surfaces of the balls 9 and 9. In FIG. 6, there are gaps 27 and 27 (see FIG. 6) that are part of the spaces between the rolling elements 23a and 23a. In the present example, these gaps 27 and 27 are connected to the projections 24a. 24a can be made smaller on both sides in the circumferential direction. For this reason, the volume of the inter-roller space 23b, 23b formed between each of the convex portions 24a, 24a and the inner ring raceway 6 and the outer ring raceway 8 is further reduced as compared with the case of the first example. I can do things. As a result, the amount of lubricating oil staying in the spaces between the rolling elements 23b and 23b can be further reduced, so that the stirring resistance of the lubricating oil and the torque loss (rotational resistance) of the thrust ball bearing 5a can be further reduced.

  Further, since the cylindrical surface portions 26 and 26 constituting the inner surfaces of the pockets 12a and 12a are communicated with the outer peripheral surface of the main body 11b, the lubricating oil supplied into the pockets 12a and 12a is efficiently used. We can discharge well. For this reason, the lubricating oil does not easily stay in the pockets 12a and 12a, and the stirring resistance of the lubricating oil can be reduced also from this surface.

  Furthermore, in the case of this example, the positioning of the cage 10b in the axial direction can be restricted by so-called ball guidance. For this reason, it is possible to effectively prevent interference (rubbing) between the axial side surface (both inner and outer side surfaces) of the main body 11b and the outer surface of the power roller 3 and the inner surface of the outer ring 7 as the mating surface.

  Further, when manufacturing the cage 10b of this example having the above-described configuration, for example, when the cage 10b is made of a metal material, the portion between the pockets 12a and 12a adjacent to each other in the circumferential direction is formed. After forming an intermediate material having a width dimension in the circumferential direction wider than that of the finished product, it can be formed by cutting or grinding the circumferential side surface with a rotary cutting tool. Further, when the cage 10b is made of a synthetic resin, a mold having an outer surface shape that matches the inner surface shape of each of the pockets 12a and 12a is used, and after the injection molding, the mold is attached to each of the pockets 12a and 12a. It can be formed by pulling out from the inside to the outer diameter side of the cage 10b. However, also in the case of this example, the main body 11 (see FIG. 7) whose wall thickness is constant in the diametrical direction and the projections 24a and 24a are separately made, and then joined together to hold the holding. It can also be set as the vessel 10b.

In addition, as a prior art document related to this example, there is an invention described in the above-mentioned patent document 6, but the invention according to this patent document 6 is different from the case of this example in that the inner surface of each pocket is mainly used. It is configured by making the spherical surface portion and the cylindrical surface portion continuous in the axial direction, and is not intended to enlarge each of the convex portions 24a and 24a as in this example.
About another structure and an effect, it is the same as that of the case of the 1st example of embodiment mentioned above.

[Third example of the embodiment of the present invention]
FIG. 12 shows a third example of an embodiment of the present invention corresponding to claims 1, 2, 5, and 7. The feature of this example is that, with respect to the structure of the first example of the above-described embodiment, between the axially opposite side surfaces of the main body 11c constituting the cage 10c, and the outer surface of the power roller 3 and the inner surface of the outer ring 7. The sum of the gaps formed is regulated according to the diameter direction position of the main body 11c. Specifically, gaps (thickness in the axial direction) formed between the inner peripheral edge portion 18 of the main body 11c and the inner diameter side shoulder portion 21a of the power roller 3 and the inner diameter side shoulder portion 20a of the outer ring 7 respectively. the sum _{(a in + a out = W} i) of Is), between the outer edge portion 19 of the main 11c, the outer diameter shoulder portion 20b of the outer diameter side shoulders 21b and the outer ring 7 of the power roller 3 _Are smaller than the sum of the gaps (thickness in the axial direction) (b _in + b _out = W _o ) (W _i <W _o ).

Further, in the case of the present example, among the intermediate portions in the diameter direction on both side surfaces in the axial direction of the main body 11c, the convex portions 24, 24 formed in the portion between the pockets 12 adjacent in the circumferential direction, The sum (t _in + t _out = W _m ) of the gap (t _in ) formed between the inner ring 6 and the gap (t _out ) formed between the outer ring raceway 8 and W _i <W _m <are regulated so as to satisfy the relation of W _o.

  In the case of this example having the configuration as described above, the following problems can be solved. That is, during the operation of the toroidal-type continuously variable transmission, each trunnion 4 (see FIG. 19) is elastically deformed in a direction in which the inner surface thereof is a concave surface in accordance with the thrust load received by the power roller 3. Therefore, as in this example, when the size of the gap formed between the axially opposite side surfaces of the main body 11c and the mating surface is not restricted, the outer peripheral edge portion 19 of the main body 11c is There is a possibility that the power roller 3 may interfere with (rub against) the outer diameter side shoulder portion 21b of the power roller 3 or the outer diameter side shoulder portion 20b of the outer ring 7. And since the said outer periphery part 19 is a part with the long distance from a rotation center (the rotation radius is large) among the said main bodies 11c, compared with the case where other parts are slidably contacted or closely opposed to the other surface. Torque loss, and the problem of increased shear resistance of the lubricating oil.

On the other hand, in the case of this example, even when each trunnion 4 is elastically deformed, the inner peripheral edge portion 18 that is a portion of the main body 11c that is short from the rotation center (small in rotation radius). However, the inner peripheral shoulder portion 21a of the power roller 3 or the inner peripheral shoulder portion 20a of the outer ring 7 is slidably contacted or closely opposed, and the outer peripheral edge portion 19 is not slidably contacted or closely opposed. For this reason, the loss torque of the thrust ball bearing 5c and the shear resistance of the lubricating oil can be reduced. In the case of this example, the projections 24, 24 can be prevented from interfering with the inner ring raceway 6 and the outer ring raceway 8, so that the durability of the thrust ball bearing 5a is also prevented from being lowered. it can. Further, since the gaps (b _in , b _out ) between the outer peripheral edge portion 19 and the respective outer diameter side shoulders 21b, 20b can be ensured, the drainage of the lubricating oil supplied into the respective pockets 12 can be ensured. Can also be improved.

Incidentally, as a prior art document related to this example, there is an invention described in Patent Document 7, but the invention according to this Patent Document 7 is opposite in the size relationship of the gap from the case of this example, It is not intended to solve the above problems, nor can it be solved.
About another structure and an effect, it is the same as that of the case of the 1st example of embodiment mentioned above.

[Fourth Example of the Embodiment of the Present Invention]
FIG. 13 shows a fourth example of an embodiment of the present invention corresponding to claims 1 to 3, 5, and 7. In the case of this example, with respect to the structure of the second example of the above-described embodiment, gaps formed between both axial side surfaces of the main body 11d and the outer surface of the power roller 3 and the inner surface of the outer ring 7 respectively. As in the case of the third example of the above-described embodiment, the sum is controlled according to the radial position of the main body 11d.
About another structure and an effect, it is the same as that of the case of the 3rd example of embodiment mentioned above, and the 2nd example of embodiment mentioned above.

[Fifth example of the embodiment of the present invention]
14 and 15 show a fifth example of an embodiment of the present invention corresponding to claims 1, 3 to 5, and 7. FIG. In the case of this example, with respect to the structure of the second example of the embodiment described above, the pitch circle diameters (PCD _25a ) of the spherical portions 25a, 25a constituting the inner surfaces of the pockets 12b, 12b are set as the inner ring raceway 6 and the outer ring. It is made smaller than the pitch circle diameter (PCD ₉ ) of balls 9, 9 (see FIG. 1 etc.) provided between the tracks 8 (PCD _25a <PCD ₉ ). For this reason, in the case of this example, the center of curvature of each of the spherical portions 25a, 25a is positioned on the inner side in the diameter direction of the main body 11d as compared with the case of the second example.

  In the case of this example having such a configuration, the following effects can be obtained as compared with the structure of the second example. That is, in the case of the structure of the second example, a so-called ball guide configuration is adopted, so that compared with a case where a so-called track ring guide configuration is adopted, each ball 9, The ratio of the area covering the rolling contact surface 9 (see FIG. 7 and the like) increases. For this reason, for example, when the toroidal type continuously variable transmission is operated, if the radial speed applied to the thrust ball bearing causes variations in the revolution speed of the balls 9, 9, torque loss is likely to increase.

  On the other hand, in the case of this example, by making the pitch circle diameter of each spherical surface portion 25a, 25a smaller than the pitch circle diameter of each ball 9, 9, the inner surface of each pocket 12b, 12b. Among them, a size larger than the pocket gap (for example, twice the size of the pocket gap) between the portion near the inner end in the diameter direction of the main body 11d and the rolling surface of each of the balls 9,9. A gap can be formed. For this reason, even when variations occur in the revolution speed of the balls 9, 9, the inner end portion of the inner surface of each of the pockets 12b, 12b in the diameter direction of the main body 11d and the balls 9, It is possible to effectively prevent the 9 rolling surfaces from interfering with each other. Therefore, in this example, torque loss can be reduced as compared with the structure of the second example.

In addition, as a prior art document related to this example, there is an invention described in the above-mentioned patent document 8, but in the case of the invention according to this patent document 8, as in this example, the pockets 12b, 12b The inner surface is not constituted by a spherical surface portion and a cylindrical surface portion.
About another structure and an effect, it is the same as that of the case of the 2nd example of embodiment mentioned above.

[Sixth example of embodiment of the present invention]
16 to 18 show a sixth example of the embodiment of the invention corresponding to claims 1, 3, 4, 6, and 7. FIG. In the case of this example, with respect to the structure of the fifth example of the above-described embodiment, the tip of each convex portion 24a, 24a with respect to the axial direction of the main body 11e is in a virtual plane perpendicular to the axial direction of the main body 11e. Parallel flat surfaces 28, 28 are formed.

  In the case of this example having such a configuration, it becomes easy to manage the height of each of the convex portions 24a and 24a. That is, when the bus bar shape of each convex portion 24, 24a is a single arc shape as in the case of each example described above, for example, when performing an inspection process using a measuring tool such as a caliper, It is difficult to accurately measure the height dimension (projection amount) of each convex portion 24, 24a. On the other hand, in the case of this example, since the flat surfaces 28 and 28 are formed at the tips of the convex portions 24a and 24a, the height of the convex portions 24a and 24a can be easily set. And it can measure accurately.

Further, by forming the flat portions 28, 28, the convex portions 24a, 24a are more easily displaced when the cage 10b is displaced in the axial direction than when the flat portions 28, 28 are not formed. Interference with the inner ring raceway 6 and the outer ring raceway 8 can be made difficult. Furthermore, depending on the shape of each convex portion (for example, in the case of a greatly offset shape), when the cage moves in the diametrical direction, it is difficult to make these convex portions contact the inner ring raceway 6 and the outer ring raceway 8. You can also. Further, in the case of this example, it is possible to reduce the weight of the cage 10b and reduce the material cost.
About another structure and an effect, it is the same as that of the case of the 5th example of embodiment mentioned above.

  Each example of the embodiment described above has been described for the case where a ball is used as a rolling element. However, with respect to the structures of the first example and the third example of the embodiment described above, a tapered roller is used as the rolling element. (Tapered rollers) can also be used. In this case, convex portions having a triangular cross section (or a trapezoidal cross section) can be formed in a portion between pockets adjacent in the circumferential direction. And also when using a tapered roller as a rolling element in this way, the effect similar to the case where a ball is used as a rolling element can be obtained. In addition, the shape of each convex portion is not limited to the shape of each example of the embodiment described above, and can be freely designed as long as a part of each space (space between rolling elements) can be blocked. it can.

  Although the present case has been described with reference to a thrust rolling bearing used for a power roller of a toroidal-type continuously variable transmission, the present invention can also be applied to a thrust rolling bearing used for a gear train or other parts. That is, even in the gear train or other parts, it is necessary to supply a sufficient amount of lubricating oil to the thrust rolling bearing, and there is a problem that the agitation resistance of the lubricating oil increases when the thrust rolling bearing is operated. There is a fear. Even in such a case, in a thrust rolling bearing having an outer ring raceway, an inner ring raceway, rolling elements and a cage, the cage is intermittently provided in a ring-shaped main body and a plurality of circumferential directions of the main body. Pockets that are formed and each has a pocket for holding the rolling elements so as to be able to roll freely, and are adjacent to each other in the circumferential direction among the diametrically intermediate portions on both axial sides of the main body. Protrusions that block a part of the space existing between the respective inter-portions and the inner ring raceway and the outer ring raceway are provided at the intermediate portions. Thereby, even in the thrust rolling bearing incorporated in the gear train as described above or other parts, the stirring resistance of the lubricating oil can be suppressed.

The partial cutaway perspective view of a power roller unit which shows the 1st example of embodiment of this invention. Similarly sectional drawing of a power roller unit. The A section enlarged view of FIG. 2 similarly. The perspective view which similarly extracts and shows a holder | retainer. The front view of the holder | retainer shown in the state which similarly hold | maintained the ball in each pocket. Similarly BB sectional drawing of FIG. The perspective view which similarly shows one example of the manufacturing method of a holder | retainer. The figure similar to FIG. 2 which shows the 2nd example of embodiment of this invention. The same figure as FIG. The same figure as FIG. Similarly CC sectional drawing of FIG. The figure similar to FIG. 2 which shows the 3rd example of embodiment of this invention. The figure similar to FIG. 2 which shows the 4th example similarly. The front view of a holder which shows the 5th example similarly. Similarly DD sectional drawing of FIG. The perspective view of the holder | retainer which shows the 6th example of embodiment of this invention. Similarly front view. EE sectional drawing of FIG. 17 similarly. Sectional drawing which shows an example of a conventional structure. Sectional drawing which shows another example of a power roller unit. The front view of the holder | retainer shown in the state which similarly hold | maintained the ball in each pocket.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Input disk 2 Output disk 3 Power roller 4 Trunnion 5, 5a Thrust ball bearing 6 Inner ring track 7 Outer ring 8 Outer ring track 9 Ball 10, 10a, 10b Cage 11, 11a-11e Main body 12, 12a, 12b Pocket 13 Support shaft part DESCRIPTION OF SYMBOLS 14 Pivot shaft part 15 Oil supply hole 16 Branch hole 17 Concave groove 18 Inner peripheral edge part 19 Outer peripheral edge part 20a Inner diameter side shoulder part 20b Outer diameter side shoulder part 21a Inner diameter side shoulder part 21b Outer diameter side shoulder part 22 Flat surface part 23, 23a 23b Space between rolling elements 24, 24a Convex portion 25, 25a Spherical surface portion 26 Cylindrical surface portion 27 Gap 28 Flat surface

Claims (7)

  An input disk and an output disk that are supported concentrically so that they can freely rotate relative to each other, and are provided at a portion between these two disks in the axial direction of these two disks. A plurality of trunnions that are swingable about a pivot provided at a position twisted with respect to the central axis, and one for each trunnion in a state protruding from the inner surface of each trunnion A plurality of support shafts, a plurality of power rollers sandwiched between the two disks while being rotatably supported around each of the support shafts, an outer surface of each of the power rollers, and each of the power rollers. A thrust rolling bearing provided between the inner surface of the trunnion and each of the thrust rolling bearings formed on the outer surface of each of the power rollers. A track, an outer ring raceway formed on the inner side surface of the outer ring installed on the inner side surface of each trunnion, a plurality of rolling elements provided between the inner ring raceway and the outer ring raceway so as to roll freely, and In the toroidal-type continuously variable transmission that is composed of a cage that holds each rolling element, the cage is formed intermittently at a plurality of locations in the circumferential direction of the annular main body, A pocket for holding the rolling elements in a freely rollable manner on the inner side, and between the pockets adjacent to each other in the circumferential direction among the diametrically intermediate portions on both axial sides of the main body. A toroidal-type continuously variable transmission, characterized in that a portion is provided with a convex portion that closes a part of the space existing between each of these portions and the inner ring raceway and the outer ring raceway.   2. The sum of gaps formed between both axial side surfaces of the main body and the outer surface of the power roller and the inner surface of the outer ring is smaller at the inner peripheral edge portion than at the outer peripheral edge portion of the main body. Toroidal continuously variable transmission.   Both side surfaces of each convex portion in the circumferential direction of the main body constitute a part of the inner surface of each pocket, and the inner surface of each pocket is an inner spherical surface portion and an outer cylindrical surface portion in the diameter direction of the main body. The toroidal stepless device according to any one of claims 1 to 2, wherein each cylindrical surface portion communicates with the outer peripheral surface of the main body. transmission.   The toroidal type continuously variable transmission according to claim 3, wherein a pitch circle diameter of a spherical surface portion constituting an inner surface of each pocket is smaller than a pitch circle diameter of each rolling element.   The generatrix of each convex part is a single circular arc shape, and the curvature radius of the generatrix shape of each of these convex parts is smaller than the curvature radius of an inner ring track and an outer ring track. The toroidal type continuously variable transmission described in 1.   5. The flat surface parallel to a virtual plane perpendicular to the central axis of the main body is provided at the tip of each convex portion with respect to the axial direction of the main body, according to claim 1. Toroidal continuously variable transmission.   The toroidal-type continuously variable transmission according to any one of claims 1 to 6, wherein a lubricating oil passage that communicates the inner peripheral edge of the main body and each pocket is provided on an axial side surface of the main body. .

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