JP5696468B2 - Manufacturing method of toroidal type continuously variable transmission - Google Patents

Description

  The present invention relates to an improvement in a toroidal continuously variable transmission that 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. Specifically, a cage with good quality can be stably obtained by devising a manufacturing method of a cage incorporated in a thrust rolling bearing for supporting a power roller constituting a toroidal type continuously variable transmission. The manufacturing method to be realized is realized.

  FIG. 11 shows an example of a toroidal-type continuously variable transmission used as an automatic transmission for an automobile. This toroidal-type continuously variable transmission is called a double cavity type, and has a pair of input disks 1, 1 whose axial side surfaces facing each other are toroidal curved surfaces, and the axial side surfaces of both input disks 1, 1. A plurality of power rollers 3 and 3 are sandwiched between a pair of output disks 2 and 2 each having a toroidal curved surface. During operation, the rotations of the input disks 1 and 1 are transmitted to the output disks 2 and 2 via the power rollers 3 and 3. The power rollers 3 and 3 are rotatably supported by trunnions 4 and 4, respectively. The trunnions 4 and 4 are pivots (twisted positions with respect to the central axes of the disks 1 and 2). Oscillating displacement centered around (not shown) is supported freely. When changing the transmission ratio between the two disks 1 and 2, rolling between the peripheral surfaces of the power rollers 3 and 3 and the inner surfaces of the input disks 1 and 1 and the output disks 2 and 2 is performed. Change the position of the contact part (traction part).

  During operation of the toroidal type continuously variable transmission as described above, the power rollers 3 and 3 rotate at a 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. The thrust load applied to can be supported freely. As shown in FIG. 12, the conventional thrust ball bearings 5 and 5 are installed on the inner ring raceway 6 formed on the outer surface (lower surface in FIG. 12) of each power roller 3 and on the inner surface of each trunnion 4. The outer ring raceway 8 formed on the inner side surface of the outer ring 7 (the upper surface in FIG. 12), balls 9 and 9 provided between the inner ring raceway 6 and the outer ring raceway 8 so as to roll freely, and each of these balls 9 , 9 and a cage 10 that holds 9. In the structure shown in FIG. 12, unlike the structure shown in FIG. 11, the outer ring 7 is supported by the support shaft 11 for rotatably supporting the power rollers 3 and the power rollers. 3 is integrally formed with each trunnion 4 with a pivot shaft 12 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.

  Further, the cage 10 is provided with a plurality of column portions 15 between the inner diameter side and outer diameter side rim portions 13 and 14 arranged concentrically with each other in the radial direction intermittently in the circumferential direction, A portion between the column portions 15 adjacent to each other in the circumferential direction serves as a pocket 16 for holding the balls 9 and 9 so as to roll freely. In order to make these pockets 16 have a circular shape, the shape of each of the column portions 15 as viewed from the axial direction of the cage 10 is a drum shape in which the radial intermediate portion is constricted. With respect to the axial direction of the cage 10, the inner diameter side and outer diameter side rim portions 13, 14 and the column portions 15 are substantially uniform in thickness. The thrust ball bearing 5 configured to include such a cage 10 supports the thrust load applied to the power rollers 3 during operation of the toroidal continuously variable transmission, and the power rollers 3 are operated at high speed. Allow to rotate at. For this reason, it is necessary to supply a sufficient amount of lubricating oil to the thrust ball bearing 5 during operation, and to lubricate and cool each part.

  However, when a sufficient amount of lubricating oil is fed into the thrust ball bearing 5 including the cage 10 having the above-described structure for lubrication, the stirring resistance of the lubricating oil is reduced during operation of the toroidal continuously variable transmission. growing. And the rotational resistance (dynamic torque) of the power roller 3 supported by the thrust ball bearing 5 is increased, and the transmission efficiency of the toroidal type continuously variable transmission is deteriorated. That is, since the thickness of the conventional cage 10 is constant over the diameter direction, the circumferential direction between the axial side surfaces of the cage 10 and the inner ring raceway 6 and the outer ring raceway 8 is increased in the circumferential direction. It is unavoidable that a considerable amount of lubricating oil stays in the portion partitioned on both sides in the circumferential direction by the rolling surfaces of adjacent balls 9, 9 (the portion exposed from the cage 10). Then, when the toroidal type continuously variable transmission is operated, the balls 9 and 9 revolve while scraping the accumulated lubricating oil, and the rotational resistance of the power roller 3 is determined based on the stirring resistance of the lubricating oil. Becomes larger.

  As a structure for reducing the stirring resistance that increases due to such a cause, Patent Document 1 describes a structure as shown in FIGS. The cage 10a constituting the thrust ball bearing 5a incorporated in the improved toroidal-type continuously variable transmission is made of synthetic resin such as polyamide resin, and as shown in FIG. A plurality of column portions 15a, 15a are intermittently provided in the radial direction between the outer rim side rim portions 13a, 14a, and a portion between the column portions 15a, 15a adjacent to each other in the circumferential direction. Are formed as pockets 16a and 16a for holding the balls 9 and 9 in a rollable manner. Then, with respect to the axial direction of the cage 10a, a part of both side surfaces of each of the pillar portions 15a, 15a is provided on both the members 3, 7 in the assembled state between the power roller 3 and the outer ring 7. Convex portions 17 and 17 are provided at portions facing the inner ring raceway 6 and the outer ring raceway 8, respectively. The surface of each of the convex portions 17 and 17 is a partially cylindrical convex surface. When the respective generatrix shapes are compared, the radius of curvature of each of the convex portions 17 and 17 is the radius of curvature of the inner ring raceway 6 and the outer ring raceway 8. A little smaller than. Therefore, in the state where the thrust ball bearing 5a is assembled, most of the convex portions 17 and 17 enter inside the inner ring raceway 6 and the outer ring raceway 8, respectively. Further, a part of each of the convex portions 17, 17 is not strongly pressed against a part of the inner ring raceway 6 and the outer ring raceway 8.

  In the case of the improved structure shown in FIGS. 13 to 15 as described above, lubricating oil is present between the axially opposite side surfaces of the cage 10a and the inner ring raceway 6 and the outer ring raceway 8. The volume of the space that causes the stagnation can be sufficiently reduced. Therefore, it is possible to reduce the amount of the lubricating oil staying in each of these spaces and to prevent the lubricating oil flowing into each of the pockets 16a and 16a from flowing out into each of the spaces. As a result, the stirring resistance of the lubricating oil generated during operation of the toroidal type continuously variable transmission incorporating the thrust ball bearing 5a is reduced, the rotational resistance of the thrust ball bearing 5a is reduced, and the thrust ball bearing 5a is The transmission efficiency of the incorporated toroidal-type continuously variable transmission can be improved.

As another structure of a cage for reducing the stirring resistance, Patent Document 1 discloses a cage 10b having a structure as shown in FIG. A cage 10b incorporated in a thrust ball bearing incorporated in the toroidal type continuously variable transmission is made of a synthetic resin such as polyamide resin, and includes an annular inner rim portion 13b and a plurality of column portions 15b and 15b. Yes. Each of the column portions 15b and 15b has one end portion (radially inner end portion) coupled to a circumferentially equidistant position on the outer peripheral surface of the inner diameter side rim portion 13b, and the other end portion (radial outer end portion). ) Is a free end that is not connected to other parts.
Further, convex portions 17a and 17a bulging in the axial direction are respectively provided in the diameter direction intermediate portions (portions sandwiched between the inner peripheral edge portion and the outer peripheral edge portion) on both side surfaces in the axial direction of the pillar portions 15b and 15b. Provided. Further, the circumferential side surfaces of the convex portions 17a and 17a, each constituting a part of the inner surface of the pockets 16b and 16b, are smooth with the circumferential side surfaces of the main body portions of the column portions 15b and 15b. It is continuous. Each of the convex portions 17 a and 17 a is formed on the inner ring raceway 6 formed on the outer surface of the power roller 3 and the inner surface of the outer ring 7 in the same manner as the cage 10 b described in Patent Document 1 described above. The outer ring raceway 8 has an outer surface shape (partial cylindrical surface shape) along each raceway groove (see FIG. 14), and most of the outer raceway 8 enters the inside of each raceway groove. And the part which is surrounded on three sides by the outer peripheral surface of the said rim | limb part 13b, and the circumferential direction side surface (including the circumferential direction side surface of each said convex part 17a, 17a) of the column parts 15b and 15b adjacent to the circumferential direction Are the pockets 16b and 16b for holding the balls 9 in a rollable manner.

  In order to manufacture the cages 10a and 10b having the above-described structure at low cost and light weight, the cage 10a is formed by injection molding a synthetic resin such as polyamide resin, polyacetal resin, or polyphenylene sulfide resin. It is preferable to make it by doing. In this case, a reinforcing material such as carbon fiber or glass fiber is mixed in the synthetic resin as necessary. In any case, in order to reduce the stirring resistance of the lubricating oil by the cages 10a and 10b obtained by injection molding the synthetic resin, the column portions 15a of the cages 10a and 10b, It is preferable that the surface of 15b, in particular, the surface of each of the convex portions 17 and 17a is made smooth (linear) in the circumferential direction.

  By the way, when the cages 10a and 10b having the structure as described above are manufactured by injection molding, there is a possibility that a phenomenon (defect) in which the surface is partially recessed, so-called shrinkage, may occur. Such shrinkage is away from the gate for injecting the molten resin into the mold, and it is part of the thickness of the thick wall and the pressure of the molten resin (cavity internal pressure) fed into the mold. It is known that it is likely to occur in places where there is a difference. On the other hand, in the case of the structure such as the cages 10a and 10b described above, the convex portions 17 and 17a are present at the radial intermediate portions of the column portions 15a and 15b, which are installed in portions away from the gate. . Moreover, the thickness of each of the pillar portions 15a and 15b is extremely large at the radial intermediate portion as compared with other portions. For this reason, when the cages 10a and 10b are injection-molded with synthetic resin, the shrinkage is likely to occur in these portions. Further, in the case of a cage having a complicated structure, such as the cages 10a and 10b, the structure of the mold to be used becomes complicated, and the pressure of the molten resin (inner pressure of the cavity) fed into the mold is large. There is a difference, and the shrinkage is likely to occur in this portion. When such a shrinkage occurs in a portion where stress is concentrated during use (such as a joint between the rim portion and the column portion), the rigidity of this portion is lowered, and the cage may be damaged. In addition, when the inner surface of the pocket is in contact with the rolling surface of the ball while the balls are held in the pocket, there is a possibility that the wear of the contact portion becomes significant.

JP 2010-156399 A

  In view of the circumstances as described above, the present invention produces a cage having convex portions on both sides of a column portion, which is incorporated in a thrust rolling bearing that rotatably supports a power roller, by injection molding a synthetic resin. Even in this case, the present invention has been invented to realize a manufacturing method that can hardly cause a phenomenon called shrinkage.

The toroidal type continuously variable transmission that is the object of the manufacturing method of the present invention is similar to the generally known half-toroidal toroidal type continuously variable transmission, an input disk and an output disk, a plurality of trunnions, A plurality of support shafts, a plurality of power rollers, and a plurality of sets of thrust ball bearings are provided.
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 in 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 trunnion so as to protrude from the inner surface of each trunnion.
Each of the power rollers is sandwiched between the disks while being rotatably supported around the support shafts.
Furthermore, each said thrust ball bearing is provided between the outer surface of each said power roller, and the inner surface of each said trunnion.

  Each thrust ball bearing has an arc-shaped inner ring raceway formed on the outer surface of each power roller, and an arc-shaped cross-section formed on the inner surface of the outer ring installed on the inner surface of each trunnion. It comprises an outer ring raceway, a plurality of balls that are provided between the inner ring raceway and the outer ring raceway so as to roll freely, and a cage that holds these balls.

  In addition, this cage is made by injection molding synthetic resin, and is formed intermittently at a plurality of circumferential rim portions in the circumferential direction and at a plurality of circumferential directions of the rim portions, respectively. A plurality of pillars arranged in the radial direction, and pockets provided between the pillar parts adjacent to each other in the circumferential direction to hold each of the balls one by one in a freely rollable manner. It is provided. Further, a part of both side surfaces of each column portion in the axial direction of the cage exists between the respective column portions and the inner ring track and the outer ring track in a portion facing the inner ring track and the outer ring track. Convex portions are provided to block a part of the space.

In particular, in the manufacturing method of the toroidal type continuously variable transmission according to the present invention, the cage is integrally molded by primary injection molding with the rim portion and the base column portion that is the basis of each column portion. After obtaining the elementary holder body, the respective parts constituting the convex portions and the pillar portions are formed by molding each elementary pillar portion of the elementary holder body by secondary injection molding.
When carrying out the production method of the toroidal type continuously variable transmission of such invention, additionally, the by the primary injection molding, it can be molded thickness in the axial direction of the element retainer member constant .
Or, in addition, by the primary injection molding , on the circumferential side surface of the columnar portion of the element holder body, the engagement of the convex portion, the concavo-convex portion, etc. that engages with the portion to be molded by the secondary injection molding. A joint can be formed .

Or, in addition, by the primary injection molding , on the side surface in the axial direction of the elementary column portion of the element holder body, the engagement with the portion to be molded by the secondary injection molding, engagement of a convex portion, a concavo-convex portion, etc. A part can be formed.

Furthermore, in addition, a part of the circumferential side surface of the element pillar portion of the element holder body can be exposed to be in contact with the balls.
Alternatively, for example, the fluidity of the resin used for secondary injection molding can be made higher than the fluidity of the resin used for primary injection molding.

As described above, in the case of the manufacturing method of the toroidal type continuously variable transmission according to the present invention, the retainer of the thrust ball bearing constituting the toroidal type continuously variable transmission is composed of primary injection molding and secondary injection molding. It is manufactured in two steps. Of these, the structure of the base holder body molded by the primary injection molding is a part having a remarkably large thickness compared to other parts (such as a convex part formed at the radial intermediate part of the axial circumferential surface of each column part) ) Is not included. For this reason, it is possible to suppress the occurrence of significant shrinkage that may cause cracks or wear in the element holder body. On the other hand, regarding the part to be molded by secondary injection molding, the absolute value of the wall thickness can be suppressed by the thickness of the columnar portion of the element holder body, and even if the shrinkage occurs, the degree is kept low. It is done. As a result, the cage constituting the thrust ball bearing having sufficient strength can be stably manufactured, and as a result, the durability of the toroidal-type continuously variable transmission can be improved and the manufacturing cost can be reduced.
In particular, in the case of the invention described in claim 1 , since the thickness in the axial direction of the element holder body is made constant by the primary injection molding, it is more effective that the element holder body is contracted. Can be suppressed.
Further, in the case of each of the inventions described in claims 2 to 3 , the element holder formed by primary injection molding based on the presence of the engaging portion (convex portion, uneven portion, etc.) formed by the primary injection molding. It is possible to increase the bonding force between the body pillar portion and the portion formed by secondary injection molding. Further, by forming a convex portion as the engaging portion, the thickness of the portion molded by secondary injection molding that matches the convex portion can be made thinner. For this reason, the occurrence of shrinkage in this portion can be suppressed.
In addition, when the fluidity of the resin used for the secondary injection molding is made higher than the fluidity of the resin used for the primary injection molding, the occurrence of shrinkage is suppressed while ensuring sufficient strength as the entire cage, A cage having good quality can be manufactured more stably. That is, it is higher than the fluidity of the resin used for the primary injection molding. That is, the element holder body to be molded by primary injection molding has a relatively simple structure, but a part that requires high strength or wear resistance (the joint between the rim part and the pillar part, or the part of the pillar part). It is a circumferential side surface and is a contact portion with each ball or the vicinity of this contact portion). For this reason, in the primary injection molding, high strength can be obtained, but even if a resin having a property that the flowability is low and the filling property to the cavity of the mold is slightly low is used, It can be manufactured stably. On the other hand, the structure of the part molded by the secondary injection molding is a part that is relatively complicated than the structure of the part molded by the primary injection molding, but does not require much strength and wear resistance. For this reason, in the secondary injection molding, it is not possible to obtain a higher strength than the resin used in the primary injection molding, but it is possible to use a resin having a high fluidity and a high filling property into the mold cavity. . As a result, the effects as described above can be obtained.
Further, in the case of the invention described in claim 4 , a part of the circumferential side surface of the element pillar portion of the element holder body having sufficient strength, which is molded by primary injection molding, is brought into contact with each ball. Therefore, it is possible to improve the durability of the cage, and further improve the durability of the toroidal continuously variable transmission.

The perspective view of the element holder body which shows the 1st example of embodiment of this invention. Similarly, the perspective view of the cage after completion. The perspective view of the element holder body which shows the 2nd example of embodiment of this invention. Similarly, the perspective view of the cage after completion. The perspective view of an element holder body which shows the 3rd example of an embodiment of the invention. Similarly, the perspective view of the cage after completion. The perspective view of an element holder body which shows the 4th example of an embodiment of the invention. Similarly, the perspective view of the cage after completion. The perspective view of an element holder body which shows the 5th example of an embodiment of the invention. Similarly, perspective view of the cage after completion Sectional drawing of the toroidal type continuously variable transmission conventionally known. Similarly, sectional drawing of a power roller unit. The partial cut perspective view of the power roller support part incorporating the improved thrust ball bearing. Similarly, a sectional view. Similarly, the perspective view shown in the state which took out the holder | retainer. The perspective view which shows another example of the holder | retainer which comprises the improved thrust ball bearing.

[First example of embodiment]
1 and 2 show a first example of an embodiment of the present invention corresponding to claims 1 and 4 . The feature of the present invention including this example is that the method of manufacturing the retainer 10c of the thrust ball bearing constituting the toroidal type continuously variable transmission is devised. The basic structure (after completion of assembly) of the cage 10c is the same as the cage 10b having the conventional structure shown in FIG. The structure of the other toroidal continuously variable transmission is the same as that of the conventional toroidal continuously variable transmission shown in FIG. For this reason, the illustration and description regarding the equivalent part are omitted or simplified, and the following description will be focused on the characteristic part of this example.

In the case of the manufacturing method of the toroidal type continuously variable transmission of this example, the thrust ball bearing cage 10c constituting the toroidal type continuously variable transmission is subjected to a two-stage process of primary injection molding and secondary injection molding. Build separately.
First, an element holder body 18 having a structure as shown in FIG. 1 is molded by the primary injection molding. The element holder 18 is made of a glass fiber reinforced plastic (GFRP) or a carbon fiber reinforced plastic comprising a glass fiber in a synthetic resin such as polyamide 66, polyamide 46, polyphenylene sulfide (PPS), polybutylene terephthalate (PBT). (CFRP) or polyether ether ketone resin (PEEK) is produced by injection molding. The element holder body 18 includes an annular rim portion 19 and a plurality of element pillar portions 20 and 20.
Each of the columnar portions 20 and 20 has one end portion (radially inner end portion) coupled to a circumferentially equidistant position on the outer peripheral surface of the rim portion 19 and the other end portion (radial outer end portion). Is a free end that is not connected to other parts. Further, the thickness H ₁₈ in the axial direction of the rim portion 19 and each of the columnar portions 20 and 20 is constant.

Once the element holder 18 as described above is obtained, then, by the secondary injection molding, the element column parts 20 and 20 of the element holder body 18 are axially arranged in the element column parts 20 and 20. Each column part 15c, such as convex parts 17c, 17c and pockets 16c, 16c, which bulge in the axial direction, in the radial direction intermediate part (the part sandwiched between the inner peripheral part and the outer peripheral part) on both side surfaces, The remaining part constituting 15c (the part other than the element holder 18 shown in FIG. 2) is formed to form a holder 10c as shown in FIG. In the secondary injection molding, polyamide 66, polyamide 46, polyphenylene sulfide (PPS), polybutylene terephthalate (PBT) and the like have higher fluidity in the molten state than the synthetic resin used in the primary injection molding (glass Synthetic resin is used which does not contain fibers or carbon fibers or has a low content. Moreover, the part which contact | engages these each ball | bowl 9 in the state which hold | maintained each ball | bowl 9 (refer FIG. 14) in each pocket 16c, 16c among the circumferential direction both sides | surfaces of each said elementary pillar part 20 and 20 (FIG. 2). In this case, the exposed portions 21 and 21 that are not covered with the resin used in the secondary injection molding are the portions of the elementary column portions 20 and 20 indicated by solid lines). Each of the exposed portions 21 and 21 is formed by performing the secondary injection molding in a state in which a part of each of the elementary column portions 20 and 20 is pressed against the inner surface of the cavity during the secondary injection molding. However, at the time of secondary injection molding, the exposed portions 21 and 21 may be formed by shaving or the like after covering the portions corresponding to the exposed portions 21 and 21 with a synthetic resin. Even in the case where a part of both sides in the circumferential direction of the base pillars 20 and 20 is not exposed in this way, the portions that come into contact with the balls 9 formed by secondary injection molding are extremely thick. There is little possibility of significant shrinkage.
Further, the same resin can be used as the resin used in the primary injection molding and the secondary injection molding. Thus, when the resin used in the primary injection molding and the secondary injection molding is the same resin, the resin used in the secondary injection molding is a solid lubricant such as molybdenum disulfide, graphite, or a fluorine compound. One kind or a plurality of kinds of solid lubricants may be included.

As described above, in the case of the manufacturing method of the toroidal type continuously variable transmission of this example, the thrust ball bearing cage 10c constituting the toroidal type continuously variable transmission is divided into primary injection molding, secondary injection molding, The process is divided into two stages. Of these, the structure of the element holder body 18 formed by primary injection molding is a portion having a larger thickness than the other portions (formed at the radial intermediate portion of the axial circumferential surface of each of the column portions 15c and 15c). The thickness H _{18 in the} axial direction is constant. On the other hand, regarding the portion to be molded by secondary injection molding, the absolute value of the thickness of each portion is not particularly increased by the thickness of each of the columnar portions 20 and 20 of the element holder 18. For this reason, it is possible to prevent the cage from cracking and the occurrence of shrinkage causing wear, and to improve the durability of the cage 10c constituting the thrust ball bearing, and further to the durability of the toroidal continuously variable transmission. The improvement of sex can be aimed at. In addition, since the part shape | molded by secondary injection molding contains the part from which thickness becomes non-uniform | heterogenous, a certain amount of shrinkage may generate | occur | produce. However, unlike the portion molded by the primary injection molding, the portion molded by the secondary injection molding does not include a portion where stress is concentrated during use. For this reason, the occurrence of shrinkage in the portion molded by secondary injection molding does not cause damage that greatly impairs the durability of the cage.

  Further, the fluidity of the resin used for the secondary injection molding is set higher than the fluidity of the resin used for the primary injection molding. That is, the element holder body 18 formed by primary injection molding has a relatively simple structure, but a portion that requires high strength or wear resistance (the rim portion 19 and each of the columnar portions 20, 20). And a circumferential side surface of each of the columnar portions 20 and 20, and a contact portion with each ball 9 and the vicinity of the contact portion). For this reason, high strength can be obtained by primary injection molding, but the raw material retainer has good quality even if it is possible to use a resin with low fluidity and low filling properties to the mold cavity. The body can be manufactured stably. On the other hand, the part to be molded by secondary injection molding is a part that is relatively complicated in shape as compared with the structure of the part to be molded by primary injection molding, but is not required to have much strength and wear resistance. For this reason, in secondary injection molding, it is not possible to obtain high strength compared to the resin used in primary injection molding, but it is possible to use a resin that has high fluidity and high filling properties into the mold cavity. it can. As a result, it is possible to stably manufacture a cage with sufficient strength, thereby improving the durability of the toroidal type continuously variable transmission and reducing the manufacturing cost.

  In addition, a part of the circumferential side surfaces of each of the elementary column portions 20 and 20 of the elementary cage body 18 made of a relatively high strength resin by primary injection molding is made of resin used for secondary injection molding. By exposing without covering, each ball 9 is held in each pocket 16c, 16c, and a part of each side surface in the circumferential direction of each of the pillar portions 20, 20 and rolling of each ball 9 The surface is in direct contact. For this reason, the wear resistance of the cage 10c can be improved.

[Second Example of Embodiment]
3 to 4 show a second example of an embodiment of the present invention corresponding to claims 1, 2, and 4. FIG. In the case of the manufacturing method of the toroidal type continuously variable transmission of the present example, the radial column ends 20a, 20a of the elementary holder body 18a to be molded by primary injection molding, Engaging convex portions 22 and 22 that are engaging portions protruding in the circumferential direction are formed from both side surfaces. Further, similarly to the element holder body 18 of the first example of the above-described embodiment, the thickness H ₁₈ in the axial direction between the rim part 19 and the element pillar parts 20a, 20a is constant. In the case of this example, the engaging projections 22 and 22 are formed on both sides in the circumferential direction of the columnar portions 20a and 20a of the element holder body 18a. The engaging projections 22 and 22 may be formed only on one of the side surfaces.

  According to the manufacturing method of the toroidal type continuously variable transmission of this example as described above, the bonding force between the element holder body 18a molded by primary injection molding and the part molded by secondary injection molding is increased. Can do. That is, a centrifugal force is applied to the thrust ball bearing retainer 10d constituting the toroidal type continuously variable transmission in a used state, but the radially inner side surfaces of the respective engagement protrusions 22 and 22 and the radially inner surfaces thereof A sufficient binding force can be obtained with respect to the centrifugal force by engagement with the portion formed by the secondary injection molding facing the side surface. Other structures, operations, and effects are the same as those of the first example of the embodiment.

[Third example of embodiment]
5 to 6 show a third example of the embodiment of the invention corresponding to claims 3 and 4 . In the case of the manufacturing method of the toroidal type continuously variable transmission of this example, these both side surfaces are arranged at the radial intermediate portions of the both side surfaces in the axial direction of the respective elementary column portions 20b and 20b of the elementary holder body 18b to be molded by primary injection molding. Engagement convex portions 22a and 22a that are engagement portions protruding in the axial direction are formed. In the case of this example, the engaging protrusions 22a and 22a are formed on both side surfaces in the axial direction of the columnar portions 20b and 20b of the element holder body 18b. The engaging projections 22a and 22a may be formed only on one of the side surfaces.

  According to the manufacturing method of the toroidal type continuously variable transmission of the present example as described above, molding is performed by secondary injection molding, which is aligned with the engaging convex portions 22a and 22a of the base column portions 20b and 20b in the radial direction. The thickness in the axial direction of the portion to be made can be made thinner than in the case where these engaging projections 22a, 22a are not formed. For this reason, it is possible to more effectively suppress the occurrence of shrinkage in the portion molded by the secondary injection molding. Other structures, operations, and effects are the same as those of the second example of the embodiment.

[Fourth Example of Embodiment]
7 to 8 show a fourth example of an embodiment of the present invention corresponding to claims 3 and 4. In the case of the manufacturing method of the toroidal-type continuously variable transmission of this example, from the radial intermediate portion of the both axial side surfaces of each elementary column portion 20c, 20c of the elementary holder body 18c molded by primary injection molding to the outer end portion. The projections 22b and 22b, which are semicircular engagement parts when viewed in the circumferential direction, are formed so as to protrude from both side surfaces in the axial direction. The shape of the portion excluding the base end portion is circular. In the case of this example, the engaging projections 22b and 22b are formed on both side surfaces in the axial direction of the columnar portions 20c and 20c of the elementary holder body 18c. The engagement protrusions 22b and 22b may be formed only on one of the side surfaces.

  According to the manufacturing method of the toroidal type continuously variable transmission of the present example as described above, the secondary injection that is aligned with the positions of the engaging projections 22b and 22b of the base pillars 20c and 20c in the radial direction. The thickness in the axial direction of the portion to be molded by molding can be made sufficiently thinner as compared with the case where these engagement convex portions 22b and 22b are not formed. In particular, if the shapes of both side surfaces in the axial direction of the respective engaging convex portions 22b and 22b are made to conform to the shapes of the both side surfaces in the axial direction of the convex portions 17c and 17c molded by secondary injection molding, During injection molding, the axial thickness of this part can be made constant. As a result, it is possible to more effectively suppress the occurrence of shrinkage in the portion molded by secondary injection molding. Other structures, manufacturing processes, operations, and effects are the same as those of the third example of the embodiment.

[Fifth Example of Embodiment]
9 to 10 show a fifth example of the embodiment of the invention corresponding to claims 3 and 4 . In the case of the manufacturing method of the toroidal-type continuously variable transmission of this example, it is hung from the inner end to the outer end on both side surfaces in the axial direction of the elementary column portions 20d, 20d of the elementary holder body 18d molded by primary injection molding, Engagement concavo-convex parts 23 and 23 which are engaging parts are formed. Other structures, manufacturing processes, operations, and effects are the same as those of the second example of the embodiment. In the case of this example, the engaging uneven portions 23 and 23 are formed on both side surfaces in the axial direction of each of the columnar portions 20d and 20d of the element holder body 18d. The engaging irregularities 23 and 23 may be formed only on one of the side surfaces. Moreover, you may form an engagement uneven | corrugated | grooved part in the circumferential direction side surface.

The cage incorporated in each of the embodiments described above includes a plurality of column portions that are radially outward from the radially outer surface at equal circumferential positions on the radially outer surface (outer circumferential surface) of the annular rim portion. It is provided in a state protruding toward the direction. However, the present invention is not limited to such a structure of the cage, and the plurality of pillar portions are arranged at equal intervals in the circumferential direction on the radially inner side surface (inner circumferential surface) of the annular rim portion. The present invention can also be applied to a structure that is provided so as to protrude radially inward from the inner side surface. Further, the present invention can be applied to a cage 10a having a structure in which rim portions 13a and 14a are provided on both inner and outer peripheral edges as shown in FIG.
Moreover, the shape of each engaging part formed in the column part of the element holder body to be molded by primary injection molding is not limited to the shape of each example of the above-described embodiment, and does not impair the moldability of temporary injection molding. Various shapes can be adopted. Moreover, it is also possible to carry out a combination of the above implementations so as not to impair the moldability of the temporary injection molding.

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, 10c, 10d Cage 11 Support shaft 12 Pivot shaft 13, 13a, 13b , 13c Inner diameter side rim part 14, 14a Outer diameter side rim part 15, 15a, 15b, 15c Pillar part
16, 16a, 16b, 16c, 11d Pocket 17, 17a, 17b, 17c Convex part 18, 18a, 18b, 18c, 18d Element holder body 19 Rim part 20, 20a, 20b, 20c, 20d Element column part 21 Exposed part 22, 22a, 22b Engagement convex part 23 Engagement uneven part

Claims (4)

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 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 ball bearing provided between the inner surface of the trunnion, and each of these thrust ball bearings includes an inner ring raceway formed on an outer surface of each of the power rollers. An outer ring raceway formed on the inner side face of the outer ring installed on the inner side face of each trunnion, a plurality of balls provided to roll between the inner ring raceway and the outer ring raceway, and holding each of these balls And a cage that
This cage is made by injection molding of synthetic resin, and is formed in an annular rim portion that is continuous in the circumferential direction, and intermittently formed at a plurality of locations in the circumferential direction of the rim portion. Provided with a plurality of pillars arranged in the direction, and a pocket provided in a portion between the pillars adjacent in the circumferential direction, each holding one of the balls one by one, in a freely rollable manner. A part of both side surfaces of each of the pillars with respect to the axial direction of the cage, and a portion facing the inner ring raceway and the outer ring raceway between the pillars and the inner ring raceway and the outer ring raceway. In the manufacturing method of the toroidal type continuously variable transmission provided with a convex portion that closes a part of the space existing in
After obtaining the element holder body by integrally molding the rim part and the element pillar part that is the basis of each pillar part by primary injection molding, and molding the cage in a constant thickness in the axial direction. A method for manufacturing a toroidal continuously variable transmission, characterized in that the convex portions and the portions constituting the column portions are formed on the respective column portions of the element holder body by secondary injection molding. 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 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 ball bearing provided between the inner surface of the trunnion, and each of these thrust ball bearings includes an inner ring raceway formed on an outer surface of each of the power rollers. An outer ring raceway formed on the inner side face of the outer ring installed on the inner side face of each trunnion, a plurality of balls provided to roll between the inner ring raceway and the outer ring raceway, and holding each of these balls And a cage that
This cage is made by injection molding of synthetic resin, and is formed in an annular rim portion that is continuous in the circumferential direction, and intermittently formed at a plurality of locations in the circumferential direction of the rim portion. Provided with a plurality of pillars arranged in the direction, and a pocket provided in a portion between the pillars adjacent in the circumferential direction, each holding one of the balls one by one, in a freely rollable manner. A part of both side surfaces of each of the pillars with respect to the axial direction of the cage, and a portion facing the inner ring raceway and the outer ring raceway between the pillars and the inner ring raceway and the outer ring raceway. In the manufacturing method of the toroidal type continuously variable transmission provided with a convex portion that closes a part of the space existing in
After obtaining the element holder body by integrally molding the rim part and the element pillar part which is the basis of each pillar part by primary injection molding, the element holder is obtained by secondary injection molding. Mold each part constituting the convex part and the pillar part on each pillar part of the body ,
A toroidal stepless machine characterized in that, by the primary injection molding, an engaging portion that engages with a portion molded by the secondary injection molding is formed on a circumferential side surface of the element pillar portion of the elementary holder body. A method for manufacturing a transmission. 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 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 ball bearing provided between the inner surface of the trunnion, and each of these thrust ball bearings includes an inner ring raceway formed on an outer surface of each of the power rollers. An outer ring raceway formed on the inner side face of the outer ring installed on the inner side face of each trunnion, a plurality of balls provided to roll between the inner ring raceway and the outer ring raceway, and holding each of these balls And a cage that
This cage is made by injection molding of synthetic resin, and is formed in an annular rim portion that is continuous in the circumferential direction, and intermittently formed at a plurality of locations in the circumferential direction of the rim portion. Provided with a plurality of pillars arranged in the direction, and a pocket provided in a portion between the pillars adjacent in the circumferential direction, each holding one of the balls one by one, in a freely rollable manner. A part of both side surfaces of each of the pillars with respect to the axial direction of the cage, and a portion facing the inner ring raceway and the outer ring raceway between the pillars and the inner ring raceway and the outer ring raceway. In the manufacturing method of the toroidal type continuously variable transmission provided with a convex portion that closes a part of the space existing in
After obtaining the element holder body by integrally molding the rim part and the element pillar part which is the basis of each pillar part by primary injection molding, the element holder is obtained by secondary injection molding. Mold each part constituting the convex part and the pillar part on each pillar part of the body ,
A toroidal-type continuously variable transmission characterized in that, by the primary injection molding, an engagement portion that engages with a portion to be molded by the secondary injection molding is formed on an axial side surface of the element pillar portion of the elementary holder body. Machine manufacturing method. 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 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 ball bearing provided between the inner surface of the trunnion, and each of these thrust ball bearings includes an inner ring raceway formed on an outer surface of each of the power rollers. An outer ring raceway formed on the inner side face of the outer ring installed on the inner side face of each trunnion, a plurality of balls provided to roll between the inner ring raceway and the outer ring raceway, and holding each of these balls And a cage that
This cage is made by injection molding of synthetic resin, and is formed in an annular rim portion that is continuous in the circumferential direction, and intermittently formed at a plurality of locations in the circumferential direction of the rim portion. Provided with a plurality of pillars arranged in the direction, and a pocket provided in a portion between the pillars adjacent in the circumferential direction, each holding one of the balls one by one, in a freely rollable manner. A part of both side surfaces of each of the pillars with respect to the axial direction of the cage, and a portion facing the inner ring raceway and the outer ring raceway between the pillars and the inner ring raceway and the outer ring raceway. In the manufacturing method of the toroidal type continuously variable transmission provided with a convex portion that closes a part of the space existing in
After obtaining the element holder body by integrally molding the rim part and the element pillar part which is the basis of each pillar part by primary injection molding, the element holder is obtained by secondary injection molding. Mold each part constituting the convex part and the pillar part on each pillar part of the body ,
A method for manufacturing a toroidal-type continuously variable transmission , wherein a part of a circumferential side surface of the element pillar portion of the element holder body is exposed to be in contact with the balls .

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