JP5953961B2 - Toroidal continuously variable transmission and manufacturing method thereof - Google Patents

Description

  The present invention relates to a generator (generator) used in, for example, an automatic transmission for a vehicle (automobile), an automatic transmission for a construction machine (construction machine), an aircraft (a fixed wing aircraft, a rotary wing aircraft, an airship, etc.), etc. The present invention relates to improvement of a half toroidal toroidal continuously variable transmission that is used as an automatic transmission for adjusting the operating speed of various industrial machines such as automatic transmissions and pumps.

  The use of a half-toroidal toroidal continuously variable transmission as a transmission for an automobile is described in many publications such as Patent Documents 1 to 4 and partially implemented, and is well known. Further, a structure in which a toroidal type continuously variable transmission and a planetary gear mechanism are combined to widen the adjustment range of the gear ratio is also described in many publications such as Patent Document 5 and has been widely known. FIGS. 11 to 12 show a first example of a toroidal type continuously variable transmission that is described in each of these patent documents and has been widely known. In the case of the first example of this conventional structure, a pair of input disks 2 and 2 are disposed around the portions near both ends of the input rotation shaft 1 in a state where the inner surfaces, each of which is a toroidal curved surface, face each other. The rotation synchronized with the rotating shaft 1 is supported. An output tube 3 is supported around the intermediate portion of the input rotary shaft 1 so as to be rotatable with respect to the input rotary shaft 1. Further, on the outer peripheral surface of the output cylinder 3, an output gear 4 is fixed at the center in the axial direction, and a pair of output disks 5 and 5 are connected to both ends in the axial direction by spline engagement. Supports the rotation synchronized with. In this state, the inner surfaces of the output disks 5 and 5, each of which is a toroidal curved surface, are opposed to the inner surfaces of the input disks 2 and 2.

  Further, a plurality of power rollers 6, 6 each having a spherical convex surface are sandwiched between the input disks 2, 2 and the output disks 5, 5. The power rollers 6 and 6 are rotatably supported by trunnions 7 and 7, respectively. The trunnions 7 and 7 are tilted with respect to the central axes of the disks 2 and 5, respectively. The shafts 8 and 8 are supported so as to be swingable and displaceable. That is, each of the trunnions 7 and 7 includes a pair of tilting shafts 8 and 8 provided concentrically with each other at both axial ends, and a supporting beam existing between the tilting shafts 8 and 8. These tilting shafts 8 and 8 are pivotally supported with respect to the support plates 10 and 10 via radial needle bearings 11 and 11, respectively.

  Each of the power rollers 6 and 6 includes support shafts 12 and 12 in which the base half portion and the tip half portion are eccentric to each other on the inner surface of the support beam portions 9 and 9 constituting the trunnions 7 and 7, respectively. Via a plurality of rolling bearings, the support shafts 12 and 12 are supported so as to be able to rotate around the front half of each of the support shafts 12 and 12 and to be slightly oscillated and displaced around the base half of each of the support shafts 12 and 12. ing. Between the outer side surfaces of the power rollers 6 and 6 and the inner side surfaces of the support beam portions 9 and 9 constituting the trunnions 7 and 7, each is a part of the plurality of rolling bearings. The thrust ball bearings 13 and 13 and the thrust needle bearings 14 and 14 are provided in order from the power rollers 6 and 6 side. Of these, the thrust ball bearings 13, 13 allow the power rollers 6, 6 to rotate while supporting a load in the thrust direction applied to the power rollers 6, 6. Each of these thrust ball bearings 13, 13 has a plurality of balls 18 between an inner ring raceway 15 formed on the outer side surface of each of the power rollers 6, 6 and an outer ring raceway 17 formed on the inner side surface of the outer ring 16. , 18 are provided to be able to roll. The thrust needle roller bearings 14, 14 support thrust loads applied to the outer rings 16, 16 constituting the thrust ball bearings 13, 13 from the power rollers 6, 6. The front half of each of the support shafts 12 and 12 is allowed to swing around the base half of each of the support shafts 12 and 12.

  During operation of the toroidal-type continuously variable transmission as described above, one input disk 2 (left side in FIG. 11) is rotationally driven by the drive shaft 19 via the pressing device 20. As a result, the pair of input disks 2 and 2 supported at both ends of the input rotating shaft 1 rotate synchronously while being pressed in a direction approaching each other. The rotation is transmitted to the output disks 5 and 5 through the power rollers 6 and 6 and is taken out from the output gear 4. When changing the gear ratio between the input rotary shaft 1 and the output gear 4, the trunnions 7, 7 are displaced in the axial direction of the tilt shafts 8, 8 by hydraulic actuators 21, 21. . As a result, the direction of the tangential force acting on the rolling contact portion (traction portion) between the peripheral surface of each of the power rollers 6 and 6 and the inner surface of each of the disks 2 and 5 changes (in the rolling contact portion). Side slip occurs). As the direction of the force changes, the trunnions 7 and 7 swing around their tilting shafts 8 and 8, and the peripheral surfaces of the power rollers 6 and 6 and the disks 2 and 8. The contact position with the inner surface of 5 changes. The circumferential surfaces of the power rollers 6 and 6 are in rolling contact with the radially outer portions of the inner surfaces of the input disks 2 and 2 and the radially inner portions of the inner surfaces of the output disks 5 and 5. By doing so, the gear ratio between the input rotary shaft 1 and the output gear 4 is increased. On the other hand, the peripheral surfaces of the power rollers 6 and 6 are arranged radially inwardly on the inner side surfaces of the input disks 2 and 2 and radially outwardly on the inner side surfaces of the output disks 5 and 5. If it is brought into rolling contact with the portion, the gear ratio between the input rotary shaft 1 and the output gear 4 becomes the deceleration side.

  When the toroidal type continuously variable transmission as described above is operated, the members used for power transmission, that is, the input and output disks 2 and 5 and the power rollers 6 and 6 are connected to the pressing device 20. It is elastically deformed based on the pressing force generated. In accordance with this elastic deformation, the input and output disks 2 and 5 are displaced in the axial direction. The pressing force generated by the pressing device 20 increases as the torque transmitted by the toroidal continuously variable transmission increases, and the amount of elastic deformation of the members 2, 5, 6 increases accordingly. Accordingly, in order to properly maintain the contact state between the inner surface of each of the input and output disks 2 and 5 and the peripheral surface of each of the power rollers 6 and 6 regardless of the fluctuation of the torque, the trunnions 7 and 7 7, a mechanism for displacing the power rollers 6 and 6 in the axial direction of the disks 2 and 5 is required. In the case of the above-described first example of the conventional structure, the tip half of each of the support shafts 12 and 12 that support the power rollers 6 and 6 is also oscillated and displaced about the base half as well. The power rollers 6 and 6 are displaced in the axial direction.

  In the case of the first example of the conventional structure as described above, the structure for displacing each of the power rollers 6 and 6 in the axial direction is complicated, and parts manufacturing, parts management, and assembly work are all troublesome and costly. It is inevitable that the volume increases. As a technique for solving such a problem, Patent Document 3 describes a structure as shown in FIGS. The feature of the second example of this conventional structure is that the power roller 6a is supported with respect to the trunnion 7a so as to support the axial displacement of the input and output disks 2 and 5 (see FIG. 11). The basic structure and operation of the toroidal type continuously variable transmission as a whole are the same as those of the first example of the conventional structure shown in FIGS.

  The trunnion 7a constituting the second example of the conventional structure exists between a pair of tilting shafts 8a and 8b concentrically provided at both ends, and between these tilting shafts 8a and 8b, and at least A support beam portion 23 having a cylindrical convex surface 22 on the inner side (upper side in FIGS. 14, 17 and 18) of the input and output disks 2 and 5 in the radial direction (the vertical direction in FIGS. 14, 17 and 18). Prepare. The two tilting shafts 8a and 8b are supported on the support plates 10 and 10 (see FIG. 12) via radial needle bearings 11a and 11a, respectively, so as to be swingable and axially displaceable.

  Further, as shown in FIGS. 14 and 17, the center axis A of the cylindrical convex surface 22 is parallel to the center axis B of the both tilt axes 8a and 8b, and the center axis B of the both tilt axes 8a and 8b. Rather than the outer side (the lower side of FIGS. 14, 17, 18) in the radial direction of the disks 2, 5. Further, a concave portion 24 having a partially cylindrical surface is radially crossed on the outer surface of the outer ring 16a constituting the thrust ball bearing 13a provided between the support beam portion 23 and the outer surface of the power roller 6a. It is provided in the state. And this recessed part 24 and the cylindrical convex surface 22 of the said support beam part 23 are engaged, and the said outer ring 16a is rockable displacement about the axial direction of each said disks 2 and 5 with respect to the said trunnion 7a. I support it.

  Further, a support shaft 12a is fixed to the center of the inner surface of the outer ring 16a integrally with the outer ring 16a, and the power roller 6a is rotatable around the support shaft 12a via a radial needle bearing 25. I support it. Furthermore, a pair of stepped surfaces 26 and 26 facing each other are provided on the inner surface of the trunnion 7a at a continuous portion between both end portions of the support beam portion 23 and the pair of tilting shafts 8a and 8b. . Then, these stepped surfaces 26, 26 and the outer peripheral surface of the outer ring 16a constituting the thrust ball bearing 13a are brought into contact with or in close proximity to each other, and any traction force applied from the power roller 6a to the outer ring 16a is selected. These step surfaces 26 and 26 can be supported.

According to the toroidal type continuously variable transmission of the second example of the conventional structure configured as described above, the power roller 6a is displaced in the axial direction of each of the disks 2 and 5, and the amount of elastic deformation of each constituent member is increased. Regardless of the change, a structure capable of appropriately maintaining the contact state between the peripheral surface of the power roller 6a and the disks 2 and 5 can be configured simply and at low cost.
That is, during operation of the toroidal continuously variable transmission, the power rollers 6a are displaced in the axial direction of the disks 2 and 5 based on elastic deformation of the input and output disks 2 and 5 and the power rollers 6a. When necessary, the outer ring 16a of the thrust ball bearing 13a that rotatably supports each of the power rollers 6a is provided with a concave portion 24 having a partial cylindrical surface provided on the outer surface and a cylindrical convex surface 22 of the support beam portion 23. The sliding surface of the cylindrical convex surface 22 is oscillated and displaced about the central axis a. Based on this oscillating displacement, a portion of the peripheral surface of each power roller 6a that is in rolling contact with one axial side surface of each disk 2, 5 is displaced in the axial direction of each disk 2, 5; The contact state is properly maintained.

  As described above, the central axis A of the cylindrical convex surface 22 is larger in diameter than the central axes B of the tilting shafts 8a and 8b, which are the oscillation centers of the trunnions 7a during the shifting operation. Exists with respect to the direction. Therefore, the radius of the rocking displacement about the central axis A of the cylindrical convex surface 22 is larger than the rocking radius at the time of the speed change operation, and both the input disks 2 and 2 and the both output disks 5, 5 Has little effect on the change in the transmission ratio between (and can be neglected or remain within an easily modifiable range).

  Compared to the first example shown in FIGS. 11 to 12, the second example of the conventional structure shown in FIGS. 13 to 18 makes it easier to manufacture parts, manage parts, and assemble, thereby reducing costs. Although easy to achieve, there is room for improvement in terms of stabilizing the shifting operation. The reason for this is that each step surface 26 is provided in a pair at each end of each support beam 23 so that the outer ring 16a can be smoothly moved and displaced about each support beam 23. , 26 to make the distance D between the outer rings 16a slightly larger than the outer diameter d (D> d). The outer rollers 16a and the power rollers 6a supported concentrically with the outer ring 16a have shafts of the support beam portions 23 corresponding to a difference (D−d) between the distance D and the outer diameter d. Displaceable in the direction.

  On the other hand, during operation of a vehicle equipped with a toroidal-type continuously variable transmission, each power roller 6a receives a force in the opposite direction from each of the disks 2 and 5, for example, during acceleration and deceleration (when the engine brake is activated). ("2Ft", well known in the technical field of toroidal continuously variable transmissions). Then, the force 2Ft causes the power rollers 6a to be displaced in the axial direction of the support beam portions 23 together with the outer rings 16a. The direction of this displacement is the same as the displacement direction of each trunnion 7 and 7 (see FIG. 12) by each actuator 21 and 21 described above, and the shifting operation is started even if the displacement is about 0.1 mm. Create a possibility. When the shifting operation is started for such a reason, the shifting operation is not directly related to the driving operation, and the driver feels uncomfortable regardless of any correction. In particular, when a shift that is not intended by the driver as described above is performed in a state where the torque transmitted by the toroidal-type continuously variable transmission is low, a sense of discomfort given to the driver tends to increase.

  In order to suppress the occurrence of the speed change operation that is not directly related to the driving operation as described above, the difference (D−d) between the distance D and the outer diameter d is made small (for example, about several tens of μm). ) Can be suppressed. However, during operation of the half-toroidal toroidal continuously variable transmission, each trunnion 7a is caused by a thrust load applied from the traction portion to each support beam portion 23 via each power roller 6a and each outer ring 16a. As exaggeratedly shown in FIG. 19, the side where the outer rings 16a are installed is elastically deformed in the direction of being recessed. As a result of this elastic deformation, the distance between the step surfaces 26, 26 provided in pairs for each trunnion 7a is reduced. Even in such a state, in order to prevent the distance D between the two step surfaces 26 and 26 from becoming smaller than the outer diameter d of each outer ring 16a, the normal state (the state where each trunnion 7a is not elastically deformed). It is necessary to ensure a certain difference between the distance D and the outer diameter d. As a result, a shift operation that is not directly related to the driving operation as described above is likely to occur particularly during driving at a low torque, which tends to increase the sense of discomfort. In particular, as described in Patent Document 5, a toroidal continuously variable transmission, a planetary gear type transmission, and a clutch device are combined, and the clutch device is used to switch between a low speed mode and a high speed mode. In the case of the transmission, the direction of the torque passing through the toroidal type continuously variable transmission is reversed in the acceleration state as the two modes are switched. For this reason, as described above, a shifting operation not directly related to the driving operation occurs, and it is easy for the driver to feel uncomfortable.

  On the other hand, in Patent Document 3, the anchor piece locked to a part of the cylindrical convex surface provided on the support beam part side and the anchor groove formed on the inner surface of the concave part on the outer ring side are engaged with each other. A structure for supporting a force 2Ft is described. However, in the case of such a structure, it is difficult to support and fix the anchor piece to the support beam portion with sufficient strength and rigidity to support the force 2Ft, and it is possible to reduce the cost and to provide sufficient reliability. It is difficult to ensure safety. There is also a structure for supporting the force 2Ft by forming a plurality of balls between the rolling grooves each having an arcuate cross section formed in a portion where the cylindrical convex surface and the concave portion are aligned with each other. Have been described. However, in the case of such a structure, when the force 2Ft increases and the surface pressure of the rolling contact portion between the rolling surface of each ball and each rolling groove increases, the inner surface of each rolling groove is increased. Indentations are formed on the inner ring, and vibration may occur when the inner rings swing and displace with respect to the trunnions. Furthermore, the force 2Ft is supported by engaging a protrusion formed on the outer peripheral surface of the support beam portion with both axial side surfaces parallel to each other and a groove formed on the inner surface of the outer ring side recess. The structure is also described. However, in the case of such a structure, in order to reduce the gap of the engaging portion between the ridge and the concave groove, during polishing processing to finish the gap between both side surfaces of the ridge with high accuracy, Damages due to polishing burn are likely to occur on both side surfaces. That is, this polishing process is performed by pressing the rotated grindstone against both side surfaces of the ridge. At this time, both side surfaces of this protrusion, which is the machining surface, are parallel to each other, in other words, because both side surfaces are perpendicular to the rotation axis of the grindstone, the temperature of both side surfaces rises and the polishing burn occurs. easy. In addition, since the axial direction of the rotating shaft of the grindstone and the pressing direction are parallel to each other, it is impossible to polish both side surfaces and the cylindrical convex surface at the same time, the processing efficiency is poor, and the manufacturing cost of the entire trunnion To rise.

[Description of Prior Invention]
20 to 27 show the structure of the prior invention relating to the toroidal type continuously variable transmission, which has been unpublished but was developed in view of the above-described circumstances and disclosed in Japanese Patent Application No. 2012-21944. The structure of the present invention is characterized in that an outer ring 16b constituting a thrust ball bearing 13a (see, for example, FIGS. 17 to 18) is provided with respect to the support beam portion 23a of the trunnion 7b to stabilize the speed change operation. The structure is to prevent the displacement of the support beam portion 23a in the axial direction while supporting the swing displacement with respect to 23a. Since the structure and operation of the other parts are the same as those of the second example of the conventional structure described above, the illustration and description of the equivalent parts are omitted or simplified. The explanation will focus on the missing part.

  The outer ring 16b engages a recess 24 provided on the outer surface of the outer ring 16b with a cylindrical convex surface 22 of the support beam portion 23a to input and output discs 2, 5 ( The swinging displacement in the axial direction (see FIG. 11) is supported. Further, a concave groove 27 formed in the circumferential direction centering on the support beam portion 23a and a ridge 28 formed on the outer peripheral surface of the support beam portion 23a are engaged with the inner surface of the concave portion 24. Thus, the axial displacement of the support beam portion 23a is limited. The above configuration is the same as the structure described in Patent Document 3 described above.

  In particular, in the case of the structure of the previous invention, the concave groove 27 is a tapered groove having a wide opening and a narrow bottom. In the case of the illustrated example, the cross-sectional shape of both inner side surfaces of the concave groove 27 is a straight line as shown in FIG. 23B and FIG. Note that the angle θ {see FIG. 23B) formed by the extension lines of these inner side surfaces and the recess 24 is about 45 degrees (40 to 50 degrees). Further, as shown in FIG. 25, the bottom of the concave groove 27 is an extension line of both inner side surfaces of the concave groove 27 and a relief concave portion 43 that is recessed from an arc surface that smoothly connects both side surfaces. The finishing of both inner surfaces is facilitated. The concave portion 24 and the concave groove 27 are processed (cutting and grinding) at the same time (without changing the processing device on the way = without performing chucking on the way). In particular, the grinding process for finishing is performed by grinding the concave portion 24 and the concave groove 27 with an integrated grindstone. Thereby, the positional accuracy (coaxiality) between the concave portion 24 and the concave groove 27 is ensured.

  The protrusion 28 is a tapered protrusion with a wide base and a narrow tip. In the case of the structure of the previous invention, both outer side surfaces of the protrusion 28 are curved in a direction protruding toward both inner side surfaces of the concave groove 27 as shown in FIG. It is a partial arc. The radius of curvature R of this partial arc is 2 mm or more. Further, portions of the outer peripheral surface of the support beam portion 23a that sandwich the protrusion 28 from both axial sides are relief recesses 34 and 34 that are recessed from the cylindrical convex surface 22 of the support beam portion 23a. This facilitates finishing of both outer side surfaces of 28. As with the case of the concave portion 24 and the concave groove 27, the outer side surfaces of the protrusion 28 and the cylindrical convex surface 22 are simultaneously processed. In particular, the grinding process for finishing is performed by grinding both outer side surfaces of the ridges 28 and the cylindrical convex surface 22 with an integrated grindstone. Thereby, the positional accuracy of both the outer side surfaces of the protrusions 28 and the cylindrical convex surface 22 is ensured.

  In the case of the structure of the prior invention as described above, the cross-sectional shape of both outer surfaces of the protrusion 28 is a convex arc, so that both outer surfaces of the protrusion 28 and both inner surfaces of the groove 27 are processed. Regardless of the error, it is possible to suppress wear of the rubbing portion between both outer side surfaces of the protrusions 28 and both inner side surfaces of the groove 27. That is, if the outer side surfaces of the ridges 28 and the inner side surfaces of the concave grooves 27 are flat surfaces having a linear cross-sectional shape, the surface pressure at the contact portion between these side surfaces can be kept low. In this case, it is difficult to make the outer surface of the protrusion 28 and the inner surface of the groove 27 facing each other completely parallel due to processing errors. If these two side surfaces are not parallel to each other, the contact at the rubbing portion between these two side surfaces becomes uneven (stress concentrates at the ends of the ridges 28 to the concave grooves 27), and wear tends to occur. Become. Therefore, the cross-sectional shape of both outer side surfaces of the two protrusions 28 is a convex arc, and it is desirable to secure a radius of curvature R of the partial arc that is the convex arc of 2 mm or more. Table 1 and FIG. 26 below show the effect of the radius of curvature R of the partial arc on the amount of wear at the rubbed portion between both outer side surfaces of the protrusion 28 and both inner side surfaces of the concave groove 27. ing. The vertical axis in FIG. 26 indicates a dimensionless value obtained by dividing the increase amount (unit: mm) of the gap due to wear by the radius of curvature R. The smaller the radius of curvature R is, the larger the allowable processing error of both outer side surfaces of the protrusion 28 and both inner side surfaces of the concave groove 27 is. However, as can be seen from Table 1 and FIG. 26, when the radius of curvature R of the partial arc is less than 2 mm, the wear amount of the rubbing portion increases rapidly. Therefore, if the curvature radius R is secured to 2 mm or more, the machining error can be allowed to some extent while keeping the wear of the rubbing portion sufficiently low.

  The width dimension of the concave groove 27 is slightly larger than the width dimension of the protrusion 28. In this case, the size relationship between the width dimensions is such that the positions of the support beam portions 23a in the radial direction match each other, and the portions that are aligned with each other in a state where the cylindrical convex surface 22 and the concave portion 24 are in contact with each other. Say by comparison of width dimensions. By restricting the size relationship between the two width dimensions as described above, the protrusion 28 does not bite into the concave groove 27 while the cylindrical convex surface 22 and the concave portion 24 are in contact with each other, and the support The swinging displacement of the outer ring 16b with respect to the beam portion 23a is performed smoothly. Further, the power beam 6a (see, for example, FIGS. 17 to 18) supported by the trunnion 7b does not transmit torque, and the support beam portion 23a and the outer ring 16b are not elastically deformed. With respect to the axial direction, the width of the concave groove 27 is larger than the width of the protrusion 28 by a portion indicated by ΔW in FIG. doing. In other words, in a state in which the support beam portion 23a and the outer ring 16b are not elastically deformed, an amount by which the outer ring 16b can be displaced in the axial direction of the support beam portion 23a with respect to the support beam portion 23a is Limited to W only.

  However, the extent to which the width of the concave groove 27 is made larger than the width of the protrusion 28 (ΔW) is kept as small as possible within the range in which the magnitude relationship between the two widths does not reverse regardless of the manufacturing error. . Specifically, the outer ring 16b is an amount that can be displaced in the axial direction of the support beam portion 23a with respect to the support beam portion 23a. Difference) is set to 0.050 mm or less. If this width difference is suppressed to 0.050 mm or less, the amount of displacement of the power roller 6a in the axial direction of the trunnion 7b can be suppressed to a small extent regardless of the movement of the actuator 21 (see FIG. 12). And when the transmission direction of the torque by the toroidal-type continuously variable transmission is reversed, it is possible to prevent an unintended shift operation from being performed and to prevent the driver from feeling uncomfortable.

  This point will be described with reference to FIG. FIG. 27 shows a combination of a toroidal-type continuously variable transmission, a planetary gear type transmission, and a clutch device, as described in Patent Document 5 described above. The state of each part at the time of the acceleration of the vehicle carrying the continuously variable transmission which switches is shown. In FIG. 27, the horizontal axis represents elapsed time, the left vertical axis represents engine speed (rotational speed), and the right vertical axis represents vehicle speed. In FIG. 27, the chain line α indicates the vehicle speed, the solid line β indicates the engine speed when the width difference ΔW is 0.125 mm, and the broken line γ indicates the difference ΔW is 0.050 mm. Represents the engine speed. When the elapsed time is 41 seconds, the clutch device is switched from the low speed mode state to the high speed mode state. As a result, the direction of torque transmission by the toroidal continuously variable transmission is reversed.

  As is clear from FIG. 27 as described above, when the difference ΔW between the two widths is set to 0.125 mm, the transmission ratio of the toroidal continuously variable transmission fluctuates abruptly. Soars. This is because the power roller 6a supported by the support beam portion 23a via the outer ring 16b is displaced in the axial direction of the support beam portion 23a as the torque transmission direction is reversed. This is because the direction of the tangential force acting on the traction portion between the peripheral surface of the power roller 6a and the axial side surfaces of the input and output disks 2 and 5 (see FIG. 11) changes. For this reason, when the engine speed rapidly increases, the driver feels uncomfortable. On the other hand, when the difference ΔW between the two widths is 0.050 mm as in the structure of the above-described invention, the toroidal-type continuously variable transmission can be used even when the torque transmission direction is reversed. The gear ratio does not change regardless of the movement of the actuator 21, and the engine speed does not increase rapidly, so that the driver does not feel uncomfortable.

  When the torque transmitted by the toroidal-type continuously variable transmission is increased, and as a result, the thrust load applied to the support beam portion 23a from the power roller 6a through the outer ring 16b is increased, the support beam portion 23a is The outer ring 16b is elastically deformed into a circular arc having a concave side. As a result, as shown by an arrow A in FIG. 24, the protrusion 28 is displaced in a direction of coming out of the groove 27, and between the outer side surfaces of the protrusion 28 and the inner surfaces of the groove 27. The gap tends to widen. However, the actual spread amount is slight. Then, since the gap tends to widen, the difference ΔW is slightly reduced in a state where the power roller 6a does not transmit torque and the support beam portion 23a and the outer ring 16b are not elastically deformed ( Even if it is suppressed to 0.050 mm or less), when transmitting a large torque, the protrusion 28 is not sandwiched between the inner surfaces of the concave groove 27, and the support beam portion 23a is the center. The swinging displacement of the outer ring 16b is smoothly performed. In addition, when the torque transmitted by the toroidal type continuously variable transmission is large, even if the engine speed changes due to a slight change in the gear ratio, the driver feels a sense of incongruity lower than when the torque is low. , Especially unlikely to be a problem.

  Further, in the case of the structure of the previous invention, through the upstream lubricating oil passage 29 formed in the trunnion 7b and the downstream lubricating oil passage 30 provided in the support shaft 12a of the outer ring 16b, Lubricating oil (traction oil) is supplied to the thrust ball bearing 13a and the radial needle bearing 25 (see FIGS. 17 to 18) provided between the outer ring 16b and the power roller 6a. Regardless of the rocking displacement of the outer ring 16b with respect to the support beam portion 23a, the downstream end opening of the upstream lubricating oil passage 29 and the upstream end opening of the downstream lubricating oil passage 30 remain in communication. For this purpose, a circular central recess having an opening diameter larger than the width dimension of the concave groove 27 at the central portion in the circumferential direction of the concave groove 27 aligned with the upstream end opening of the downstream lubricating oil passage 30. 31 is formed. In addition, a notch 32 is formed at the center in the circumferential direction of the protrusion 28, which is aligned with the downstream end opening of the upstream lubricating oil passage 29. Even when the outer ring 16b is oscillated and displaced with respect to the support beam portion 23a due to a change in torque transmitted by the toroidal-type continuously variable transmission, the upstream-side lubricating oil passage 29 and the downstream-side lubricating oil flow The passage 30 remains in communication with the notch 32 and the central recess 31. Therefore, the supply of the lubricating oil to the bearings 13a and 25 through both the lubricating oil flow paths 29 and 30 is stable regardless of the swinging displacement of the outer ring 16b centering on the support beam portion 23a. Can be done.

  In order to suppress the difference ΔW slightly (less than 0.050 mm) as in the structure of the previous invention, a recess 24 provided on the outer surface of the outer ring 16b and an inner surface of the recess 24 are formed. It is necessary to ensure good concentricity (0.015 mm or less, preferably 0.010 mm or less, more preferably 0.005 mm or less) with the concave groove 27 formed. For this reason, in the case of the structure of the prior invention, as described above, the recess 24 and the groove 27 are finished by grinding with an integrated grindstone. However, since the general-purpose grindstone has a large contact area and a large rotational resistance, the efficiency of the finishing process is lowered, and the manufacturing cost may be increased. Therefore, it is conceivable to perform finishing by grinding the concave portion 24 and the concave groove 27 simultaneously (with one chuck) with different grindstones. In any case, in order to ensure the coaxiality between the concave portion 24 and the concave groove 27, the chucking of the outer ring 16b when finishing the concave portion 24 and the concave groove 27 with high accuracy is performed. There is a need to do.

  In addition, when changing the transmission ratio of the toroidal continuously variable transmission, the trunnions 7 and 7 (see FIGS. 11 to 12) installed in different cavities in the opposite directions (the same direction with respect to the changing direction of the transmission ratio), Only the same angle is oscillated and displaced in synchronization with each other. In order to make the oscillating displacements of the trunnions 7 and 7 coincide with each other with high accuracy (to improve the shift synchronization stability of the toroidal continuously variable transmission), the power rollers 6 and 6 (FIGS. 11 to 12). )) Is regulated with high accuracy. For this reason, the size and shape of each part of the power roller unit 33 (see FIGS. 13 to 18) are regulated with high precision (particularly between the power roller units 33 incorporated in the same toroidal continuously variable transmission). There is a need to. That is, the error in the assembly height of the power roller 6a with respect to each trunnion 7a (7b), the parallelism of the outer ring raceway 17 of the outer ring 16a (16b) with respect to the axial direction of the support beam portion 23 (23a) of each trunnion 7a (7b) Similarly, it is necessary to regulate the perpendicularity of the support shaft 12a to about 0.010 mm or less (0.015 mm or less, preferably 0.010 mm or less, more preferably 0.005 mm or less).

  Further, in the toroidal continuously variable transmission as described above, when each trunnion is oscillated and displaced, the peripheral surface of the power roller protrudes radially outward of the inner surface of each disk, or the outer peripheral edge of the outer ring. In addition, it is necessary to prevent the outer peripheral edge of the cage that holds the balls constituting the thrust ball bearing from coming into contact with the inner surface of each disk. In order to solve such a problem, Patent Document 6 discloses that the tip of the support plate provided at the end of the trunnion is an inclined edge, and the inclined edge and a stopper fixed to a housing or the like are used as described above. A structure is described in which a stopper mechanism is provided that prevents the trunnion from further swinging displacement by being brought into contact when the trunnion is swung to an allowable limit. However, in the case of the structure described in Patent Document 6, a member (between the rolling contact portion between the peripheral surface of the power roller and the inner surface of each disk and the contact portion between the inclined edge and the stopper ( Power rollers, balls constituting the thrust ball bearing, outer ring, and trunnion) have a large number of points and a long distance. Therefore, there is room for improvement in terms of regulating the inclination angle of the power roller with respect to each disk with higher accuracy.

JP 2003-214516 A JP 2007-315595 A JP 2008-25821 A JP 2008-275088 A JP 2004-169719 A Japanese Utility Model Publication No. 6-43404

  In view of the circumstances as described above, the present invention makes it easy to manufacture parts, manage parts, and assemble, facilitate cost reduction, stabilize the speed change operation, and further, if necessary, each disk. Invented to realize a structure of a toroidal-type continuously variable transmission capable of regulating the inclination angle of the power roller with respect to the above and a manufacturing method thereof.

A toroidal-type continuously variable transmission that is an object of the present invention includes at least one pair of disks, a plurality of trunnions, the same number of power rollers as each of the trunnions, and the same number of thrust rolling bearings.
Each of these disks is supported concentrically with each other in such a manner that relative rotation is possible with the respective axial side surfaces facing each other, each of which is a toroidal curved surface having an arc cross section.
Each trunnion is present between a pair of tilting shafts concentrically provided at both ends of each of the trunnions, and at least an inner side surface in the radial direction of each disk. And a support beam portion having a cylindrical convex surface having a central axis that is parallel to the central axes of the two tilting axes and is located outside the central axes of the two tilting axes in the radial direction of each disk. Then, with respect to the axial direction, the rocking displacement about the tilting shaft that is twisted with respect to the central axis of each disk can be freely performed at a plurality of positions in the circumferential direction between the axial side surfaces of each disk. Provided.
Each power roller is rotatably supported on the inner side surface of each trunnion via a thrust rolling bearing, and each circumferential surface formed as a spherical convex surface is in contact with one axial side surface of each disk. Touching.
Each thrust rolling bearing is provided between the support beam portion of each trunnion and the outer surface of each power roller. And, the outer ring provided on each support beam portion side, the outer ring raceway provided on the inner side surface of each outer ring, and the inner ring raceway provided on the outer side surface of each power roller, can freely roll. A plurality of rolling elements each provided.
Further, the outer ring has a support shaft fixed at the center of the inner side surface, and the power rollers are rotatably supported around the support shaft through radial rolling bearings. Then, by engaging a concave portion provided on the outer side surface of each outer ring and a cylindrical convex surface of each supporting beam portion, each outer ring is swung with respect to each trunnion in the axial direction of each disk. While supporting the displacement, the inner surface of the concave portion is engaged with a concave groove formed in the circumferential direction around the support beam portion and a protrusion formed on the outer peripheral surface of the support beam portion. Thus, the displacement of the outer ring with respect to the axial direction of the support beam portion is limited.

  In particular, in the toroidal type continuously variable transmission of the present invention, the concave groove is a tapered groove having a wide opening and a narrow bottom. The protrusion is a tapered protrusion having a wide base and a narrow tip. Then, a step is provided on at least a part of the outer peripheral edge of the outer surface of each outer ring, and each outer ring is gripped by a chuck in a state in which the step is positioned with respect to a reference surface, and the recess and the groove, The outer ring raceway and the outer peripheral surface of the support shaft are simultaneously subjected to finishing processing such as grinding or hard turning finish (without changing the processing device in the middle = without chucking in the middle).

When implementing the toroidal continuously variable transmission of the present invention as described above, for example, as in the invention described in claim 2, the stepped portion is formed around the outer peripheral edge of the outer surface of each outer ring. Provide.
When the invention described in claim 2 is carried out, preferably, as in the invention described in claim 3, a positioning recess for positioning the chuck in the circumferential direction is provided on the outer surface of each outer ring. Provide.
Or like the invention described in Claim 4, the said level | step-difference part is provided in the axial direction of the said support beam part in the width direction both-sides part which pinches | interposes the said recessed part among the outer peripheral surface outer peripheral parts of each said outer ring | wheel.

  Preferably, when the toroidal continuously variable transmission according to the present invention is implemented, each trunnion is oscillated and displaced to an allowable limit around the two tilting axes as in the invention described in claim 5. In this case, a stopper is provided at a position where the step portion of each outer ring is engaged to prevent each trunnion from further swinging and displacement based on this engagement.

Further, in the method of manufacturing the toroidal continuously variable transmission according to the present invention described in claim 6, at least the outer peripheral edge of the outer surface of each outer ring is formed in order to produce the toroidal continuously variable transmission as described above. A step is provided in part. Then, each outer ring is gripped by a chuck in a state where the stepped portion is positioned as a reference surface, and grinding or cutting is simultaneously performed on the concave portion and the concave groove, the outer ring raceway, and the outer peripheral surface of the support shaft. Finish processing such as processing.
When the invention described in claim 6 is carried out, as in the invention described in claim 7, for example, the stepped portion is provided on the outer peripheral edge of the outer surface of each outer ring over the entire circumference. .
In the case of carrying out the invention described in claim 7, preferably, as in the invention described in claim 8, the step portion is sandwiched between the outer peripheral edge portions of the outer rings of the outer rings. Provided on both sides in the width direction.
Or like the invention described in Claim 9, the said level | step-difference part is provided in the axial direction of the said support beam part in the width direction both-sides part which pinches | interposes the said recessed part among the outer peripheral surface outer peripheral parts of each said outer ring | wheel.

According to the toroidal-type continuously variable transmission and the manufacturing method thereof of the present invention configured as described above, it is easy to manufacture parts, manage parts, and assemble work, facilitate cost reduction, and stabilize shifting operation. Furthermore, it is possible to realize a structure that can regulate the inclination angle of the power roller with respect to each disk as required.
Of these, the cost reduction is the same as the second example of the conventional structure shown in FIGS. 13 to 18 described above, and the ease of processing is the same as the structure according to the prior invention shown in FIGS. 20 to 27 described above. Therefore, it is easy to plan.

  Also, stabilization of the speed change operation can be basically achieved for the same reason as in the structure according to the previous invention. Further, in the case of the present invention, a step portion is provided on a part of the outer peripheral edge portion of the outer surface of each outer ring. Then, the outer ring is gripped by a chuck in a state where positioning is performed with the stepped portion as a reference surface, and the outer ring surface of the recess and groove of the outer ring, the outer ring raceway, and the support shaft are ground and hard-turned. Finishing processing is given. For this reason, the size and shape of each part of each outer ring (the concentricity of the concave and concave grooves, the difference in assembly height between the power roller units formed by combining the trunnion, outer ring and power roller, The degree of parallelism of the outer ring raceway with respect to the axial direction of the support beam and the perpendicularity of the support shaft can be regulated with high accuracy. As a result, the difference between the width of the concave groove and the width of the protrusion can be suppressed to a small (0.050 mm or less), and the position where the power roller is incorporated in the toroidal continuously variable transmission can be regulated with high accuracy. From this aspect, the shifting operation can be stabilized.

  According to the invention described in claim 5, the peripheral surface of the power roller protrudes radially outward of the inner surface of each disk, or holds the outer peripheral edge of each outer ring and the ball constituting the thrust ball bearing. It is possible to prevent the outer peripheral edge of the cage from coming into contact with the axial side surface of each disk. In particular, in the case of the structure of the invention described in claim 5, a member (power) that exists between the rolling contact portion between the peripheral surface of the power roller and the inner surface of each disk and a stopper that regulates the swing displacement of the trunnion. The number of points of the rollers, balls constituting the thrust ball bearing, and the outer ring) is small compared to the structure described in Patent Document 6 described above, and the distance is also short. Therefore, the inclination angle of the power roller with respect to each disk can be regulated more accurately than the structure described in Patent Document 6.

Sectional drawing (A) which takes out and shows an outer ring | wheel regarding the 1st example of embodiment of this invention, and a perspective view (B) shown in the state seen from the downward direction of (A). Similarly, sectional drawing which shows two examples of the method of giving a finishing process to the level | step difference surface formed in the outer peripheral surface outer peripheral part of an outer ring | wheel. Similarly, sectional drawing which shows the state which finishes the recessed part and recessed groove of the said outer ring | wheel, an outer ring track | orbit, and the outer peripheral surface of a support shaft. Similarly, the perspective view which shows four examples of the positioning recessed part formed in the outer surface of the said outer ring | wheel. Similarly, sectional drawing for demonstrating the structure of the stopper which controls the inclination-angle of a power roller. The figure similar to FIG. 1 which shows the 2nd example of embodiment of this invention. Similarly, the perspective view for demonstrating the method of forming a recessed part, a ditch | groove, and a level | step difference surface in the outer surface of an outer ring | wheel. Similarly, a perspective view (A) showing the process of gripping the outer ring with the chuck in the middle state and a cross-sectional view (B) showing the gripped state. Similarly, the perspective view which shows the state which finishes a recessed part and a ditch | groove of an outer ring | wheel with an integral type grindstone. Similarly, the perspective view (B) which shows the state which performs a finishing process to the recessed part of an outer ring | wheel, and the state which performs a finishing process to a ditch | groove. Sectional drawing which shows the 1st example of a conventional structure. FIG. 12 is a cross-sectional view taken along line aa in FIG. 11. The perspective view which looked at the trunnion which supported the power roller via the thrust ball bearing which shows the 2nd example of the conventional structure from the radial direction outer side of each disk. Similarly, the front view shown in the state seen from the circumferential direction of the disk. The top view seen from the upper part of FIG. The side view seen from the right side of FIG. Bb sectional drawing of FIG. Cc sectional drawing of FIG. FIG. 18 is a cross-sectional view seen from the same direction as FIG. 17, exaggeratingly showing a state where the trunnion is elastically deformed based on a thrust load applied from a power roller. Sectional drawing which shows the structure which concerns on a prior invention in the state which took out the trunnion and the outer ring | wheel for thrust rolling bearings. The perspective view similarly shown in the state which took out the trunnion and was seen from the radial inside of each disk. The perspective view similarly shown in the state which took out the outer ring | wheel for thrust rolling bearings and was seen from the radial direction outer side of each disk. Similarly, the figure (A) which shows the cross-sectional shape of the protrusion formed in the trunnion side, and the figure (B) which shows the cross-sectional shape of the ditch | groove formed in the outer ring | wheel side. Sectional drawing which shows the engagement state of the said protrusion and the said ditch | groove. The fragmentary sectional view for demonstrating the concept of the clearance gap of the engaging part of these protrusions and a ditch | groove. The diagram which shows the influence which the curvature radius of the cross-sectional shape of the side surface of a protrusion exerts on the abrasion of the engaging part of these protrusions and a ditch | groove. A diagram for explaining a situation in which the size of the gap between the engagement portion between the protrusion and the concave groove leads to a sudden change in the gear ratio at the moment when the torque passing through the toroidal continuously variable transmission is reversed. .

[First example of embodiment]
FIGS. 1-5 has shown the 1st example of embodiment of this invention corresponding to Claims 1-3, 5-7. The feature of this example is that the size and shape of each part of the power roller unit 33a can be appropriately regulated to stabilize the speed change operation, and the power roller 6a for each of the input and output disks 2, 5 (see FIG. 11). It is in the point which makes it possible to appropriately regulate the inclination angle of. Since the structure and operation of other parts are the same as the structure according to the prior invention shown in FIGS. 20 to 25 described above, the illustration and description of the equivalent parts are omitted or simplified. The explanation is centered.

  The outer ring 16c constituting the power roller unit 33a is engaged with the trunnion 7b by engaging the concave portion 24 provided on the outer surface of the outer ring 16c with the cylindrical convex surface 22 of the support beam portion 23a of the trunnion 7b. The input and output disks 2 and 5 are supported so as to be capable of swinging in the axial direction. A concave groove 27, which is a tapered groove having a wide opening and a narrow bottom, is formed on the inner surface of the concave portion 24 in the circumferential direction around the support beam portion 23a. In addition, ridges 28 (see FIGS. 21, 23 to 25), which are tapered ridges having a wide base and a narrow tip, are formed. And the displacement about the axial direction of the said support beam part 23a of the said outer ring | wheel 16c is restrict | limited by engaging the said groove 27 and this protrusion 28. FIG. The above configuration is the same as the structure according to the previous invention.

  In particular, in the case of this example, a stepped portion 34 is provided on the outer peripheral edge of the outer ring 16c over the entire circumference. As will be described later, the stepped portion 34 serves as a reference surface when finishing each portion of the outer ring 16c. Further, when the trunnion 7b is oscillated and displaced to a permissible limit around the pair of tilting shafts 8a and 8b (see FIG. 20) with the power roller unit 33a assembled in the toroidal continuously variable transmission. The contact surfaces 36, 36 of the stopper 35 are provided at the portion where the stepped portion 34 of the outer ring 16c is engaged (contacted). Thereby, the inclination angle of the trunnion 7b is limited to a certain range. In other words, when the trunnion 7b is swung to the allowable limit when the stopper 35 is fixed to a fixed part such as a casing of a toroidal-type continuously variable transmission, the contact surfaces 36, 36 of the stopper 35 are formed on the outer ring 16c. It is supported and fixed so as to engage (contact) the stepped portion 34.

  The outer ring 16c of such a toroidal-type continuously variable transmission is manufactured as follows. That is, the outer ring 16c is made by subjecting a metal material such as medium carbon steel or bearing steel to cutting or heat treatment. In the case of this example, the concave portion 24 and the concave groove 27 are simultaneously formed on the outer surface of the outer ring 16c by cutting, and after heat treatment, the outer peripheral edge of the outer surface of the outer ring 16c is spread over the entire circumference. The step 34 is formed by cutting. Next, finishing processing such as grinding or hard turning is performed on the radial step surface 45 and the axial step surface 46 constituting the step portion 34 and the outer peripheral surface of the outer ring 16c. When performing such finishing, as shown in FIG. 2A, the opening of the downstream lubricating oil passage 30 provided in the support shaft 12a and the recess provided in the tip surface of the support shaft 12a. The conical tip portions of the pair of holding jigs 38, 38 are inserted into the holes 37, respectively, and the outer ring 16c is sandwiched. In this state, by rotating these holding jigs 38, 38, the outer ring 16c is rotated, and the radial step surface 45 and the axial step surface 46 of the stepped portion 34 and the outer peripheral surface of the outer ring 16c are connected. Then, by grinding with an integrated grindstone 39 (or turning with a tool), the radial step surface 45 and the axial step surface 46 of the step portion 34 and the outer peripheral surface of the outer ring 16c are finished. (The right angle of the radial step surface 45 with respect to the rotation center axis of the support shaft 12a is also improved, and the parallelism of the axial step surface 46 and the outer peripheral surface of the outer ring 16c is also improved). In the case of this example, in order to prevent the roundness of the finishing process between the stepped portion 34 and the outer peripheral surface of the support shaft 12a from being deteriorated, a two-step chamfered portion is provided on the inner peripheral edge of the opening of the downstream-side lubricating oil passage 30. 40a and 40b are provided. However, when the roundness of the finishing process of the stepped portion 34 can be ensured, a single chamfered portion can be used. Alternatively, as shown in FIG. 2B, the inner surface of the outer ring 16c (the left side surface of FIG. 2B) is suppressed by the backup jig 44, and the outer peripheral surface of the support shaft 12a is held by the chuck 41. The outer ring 16c can be rotated by rotating the backup jig 44 and the chuck 41 in the gripped state, and the stepped portion 34 and the outer peripheral surface of the outer ring 16c can be finished.

After finishing the outer circumferential surfaces of the stepped portion 34 and the outer ring 16c, the axial end surface of the positioning jig 47 is abutted against the radial stepped surface 45, thereby positioning the support shaft 12a in the axial direction. In this state, the outer peripheral surface of the outer ring 16c is gripped by the chuck 41a, thereby positioning (centering) the outer ring 16c in the radial direction. Further, in the case of this example, positioning recesses 42 and 42 for positioning the chuck 41a in the circumferential direction are provided at two positions spaced in the radial direction of the outer surface of the outer ring 16c. Such positioning recesses 42 and 42 may be positioned in the circumferential direction of the chuck 41a. For example, various structures as shown in FIG. 4 can be adopted. 4A, in the axial direction of the support shaft 12a, the inner peripheral edge of the step portion 34 is recessed radially inward at two positions opposite to the radial direction. A long groove is provided. Or, as shown in (B) of the figure, the concave groove 27 is extended in the width direction of the outer ring 16c (in a state where the concave groove 27 is opened at both edges in the width direction of the outer surface of the outer ring 16c). And both end portions in the width direction of the concave groove 27 can be used as the positioning concave portions 42, 42. Alternatively, as shown in FIG. 5C, a groove in the width direction may be formed at two positions in the width direction on the outer surface of the outer ring 16c. Furthermore, as shown in (D) of the figure, pin holes may be provided at two positions in the width direction on the outer surface of the outer ring 16c. In any case, the positioning recesses 42, 42 of the outer ring 16c are engaged with convex portions provided on the chuck 41a side, thereby positioning the chuck 41a in the circumferential direction of the outer ring 16c.
Then, in a state where the outer peripheral surface of the outer ring 16c is gripped by the chuck 41a, the outer ring 16c is rotated by rotating the chuck 41a, the outer ring raceway 17 is rotated by the grindstone 39a, and the outer peripheral surface of the support shaft 12a is moved by the grindstone. In 39b, the outer ring raceway 17 and the outer peripheral surface of the support shaft 12a are finished by grinding. At the same time, the concave portion 24 and the concave groove 27 are ground by an integrated grindstone 39c to finish the concave portion 24 and the concave groove 27.

  According to the manufacturing method of the toroidal type continuously variable transmission of this example, the speed change operation of the toroidal type continuously variable transmission can be more reliably stabilized. That is, in the case of this example, the concave portion 24, the concave groove 27, the outer ring, with the radial step surface 45 and the axial step surface 46 of the step portion 34 formed on the outer peripheral edge of the outer ring 16c as reference surfaces. The track 17 and the outer peripheral surface of the support shaft 12a are simultaneously finished (with one chuck). For this reason, the concentricity between the concave portion 24 and the concave groove 27 can be made good (approximately 0.010 mm or less), and the outer ring 16c is in the axis of the support beam portion 23a with respect to the support beam portion 23a of the trunnion 7b. Although the amount can be displaced in the direction, rattling can be suppressed to a small amount (less than 0.050 mm). Similarly, the parallelism between the recess 24 and the outer ring raceway 17, the perpendicularity between the recess 24 and the support shaft 12a, and the error in the assembly height of the power rollers 6a with respect to the trunnions 7b are also good. (Approximately 0.010 mm or less). As a result, the speed change operation of the toroidal type continuously variable transmission can be more reliably stabilized.

  Further, in the case of this example, when the trunnion 7b swings to the allowable limit around the two tilting shafts 8a, 8b, the stepped portion 34 of the outer ring 16c and the contact surfaces 36, 36 of the stopper 35 To prevent the trunnion 7b from further swinging displacement. For this reason, the peripheral surface of the power roller 6a protrudes radially outward of the inner surface of each of the disks 2, 5, or the outer peripheral edge of the outer ring 16c or the outer peripheral edge of the cage constituting the thrust ball bearing 13a, It can prevent contacting the inner surface of each disk 2 and 5 (refer FIG. 11). In the case of this example, members (power roller 6a, thrust ball bearing 13a) existing between the rolling contact portion (traction portion) between each power roller 6a and the inner surface of each disk 2, 5 and the stopper 35 are provided. The number of balls and outer rings 16c) is smaller and the distance is shorter than the structure described in Patent Document 6 described above. Therefore, the inclination angle of each power roller 6a with respect to each disk 2, 5 can be regulated with higher accuracy.

[Second Example of Embodiment]
FIGS. 6-10 has shown the 2nd example of embodiment of this invention corresponding to Claims 1-2, 4-7, and 9. FIG. In the case of this example, as in the case of the first example of the above-described embodiment, in addition to the step 34 provided on the outer peripheral edge of the outer ring 16d over the entire circumference, the outer ring 16d A pair of left and right step portions 34a parallel to the axial direction of the support beam portion 23b (see FIG. 5) of the trunnion 7b that engages with the concave portion 24, on both sides in the width direction sandwiching the concave portion 24 among the outer peripheral edge portions of the side surface. , 34a are provided. In the case of forming such stepped portions 34a and 34a, as shown in FIG. 7, the recess 24 and the groove 27 are formed simultaneously (with one chuck) and by cutting (milling). Then, the outer ring 16d is heat treated. Thereafter, positioning of the support shaft 12a in the axial direction by abutting the end surfaces of the circumferential protrusions 48, 48 provided on the chuck 41b described below against the radial step surface 45 of the step portion 34, and the beam portion 49, 49 is engaged with the axial step surfaces 46a, 46a of the stepped portions 34a, 34a to position the outer ring 16d in the circumferential direction, and the outer ring 16d faces the chuck 41b. Press to the right of 8 (B). The outer ring 16d is gripped by the chuck 41b, thereby positioning (centering) the outer ring 16d in the radial direction. In this state, the chuck 41b is rotated to grind the outer ring raceway 17 of the outer ring 16d and the outer peripheral surface of the support shaft 12a with a grindstone. At the same time (without exchanging the chuck 41b), the concave portion 24 and the concave groove 27 are ground with an integrated grindstone 39c as shown in FIG. Alternatively, as shown in FIG. 10A, the concave portion 24 is ground along the axial direction of the support beam portion 23a (see FIGS. 20 to 21) with a grindstone 39d, and then (B) in FIG. As shown in FIG. 3, the groove 27 is ground in the circumferential direction by a grindstone 39e.

In the case of this example, the step portions 34a, 34a are provided on both sides in the width direction between which the concave portion 24 is sandwiched, of the outer peripheral edge of the outer ring 16d. Therefore, as in the case of the first example of the embodiment described above, it is necessary to provide positioning recesses 42 and 42 (see FIG. 4) for positioning the chuck in the circumferential direction on the outer surface of the outer ring 16d. Absent. Further, both the step portions 34a and 34a are provided in parallel with the central axis of the concave portion 24 having a partial cylindrical surface shape, and the engagement between the both step portions 34a and 34a and the beam portions 49 and 49 results in the chucking. Positioning in the circumferential direction of the outer ring 16d of 41b is intended. For this reason, when grinding the inner surface of the concave portion 24, poor grinding (remaining black skin) hardly occurs. In the case of this example, a step provided in the axial direction of the support beam portion 23b instead of the radial step surface 45 of the step portion 34 provided over the entire outer periphery of the outer ring 16d. The radial step surfaces 45a and 45a of the portions 34a and 34a may be surfaces that contact the contact surfaces 36 and 36 (see FIG. 5) of the stopper 35.
Since the configuration and operation of the other parts are the same as those in the first example of the embodiment, illustration and description regarding the equivalent parts are omitted.

DESCRIPTION OF SYMBOLS 1 Input rotating shaft 2 Input disk 3 Output cylinder 4 Output gear 5 Output disk 6, 6a Power roller 7, 7a, 7b Trunnion 8, 8a, 8b Tilt shaft 9 Support beam part 10 Support plate 11, 11a Radial needle bearing 12, 12a Support shaft 13, 13a Thrust ball bearing 14 Thrust needle bearing 15 Inner ring raceway 16, 16a-16d Outer race 17 Outer raceway 18 Ball 19 Drive shaft 20 Pressing device 21 Actuator 22 Cylindrical convex surfaces 23, 23a, 23b Support beam portion 24 Recess portion 25 Radial needle bearing 26 Step surface 27 Concave groove 28 Projection 29 Upstream lubricating oil passage 30 Downstream lubricating oil passage 31 Central recess 32 Notch 33, 33a Power roller unit 34, 34a Step surface 35 Stopper 36 Contact surface 37 Recessed hole 38 Holding jig 39, 39a to 39e Stone 40a, 40b chamfer 41, 41a, 41b chuck 42 positioning recesses 43 escape recess 44 backup jig 45,45a radially stepped surface 46,46a axial step surface 47 positioning jig 48 circumferential ridges 49 beam portion

Claims (9)

Comprising at least one pair of disks, a plurality of trunnions, the same number of power rollers as each trunnion, and the same number of thrust rolling bearings;
Each of these disks is supported to be capable of relative rotation concentrically with each other in a state in which each side surface in the axial direction is a toroidal curved surface having an arc cross section.
Each trunnion exists between a pair of tilting shafts provided concentrically with each other at both ends, and between the two tilting shafts, and at least the inner side surface in the radial direction of each of the disks, A support beam portion having a cylindrical convex surface, having a central axis that is parallel to the central axis of both tilting axes and that is present outside the central axes of these two tilting axes with respect to the radial direction of each disk. Oscillating displacement about the respective tilting shafts at twisted positions with respect to the central axis of each disk at a plurality of locations in the circumferential direction between the axial side surfaces of the respective disks with respect to the axial direction. It is provided freely,
Each of the power rollers is rotatably supported on the inner side surface of each trunnion via a thrust rolling bearing, and each circumferential surface having a spherical convex surface is brought into contact with one axial side surface of each disk. And
Each thrust rolling bearing is provided between the support beam portion of each trunnion and the outer surface of each power roller, and an outer ring provided on each support beam portion side, and an inner ring of each outer ring. A plurality of rolling elements are provided between the outer ring raceway provided on the side surface and the inner ring raceway provided on the outer side surface of each of the power rollers, respectively.
The outer ring of each of the thrust rolling bearings rotatably supports each of the power rollers via a radial rolling bearing around a support shaft fixed to the center of the inner surface of each of the outer rings. By engaging the concave portion provided on the outer side surface and the cylindrical convex surface of each of the support beam portions, the trunnion is supported so as to be capable of swinging displacement in the axial direction of each disk, and By engaging a concave groove formed in the circumferential direction centered on the support beam portion and a protrusion formed on the outer peripheral surface of the support beam portion with the inner surface of the recess, the shaft of the support beam portion is engaged. In the toroidal type continuously variable transmission in which the displacement in the direction is limited,
The concave groove is a tapered groove with a wide opening and a narrow bottom, and the ridge is a tapered ridge with a wide base and a narrow tip, and the outer peripheral edge of each outer ring. At least a part of the concave portion and the concave groove, the outer ring raceway, and a stepped portion that serves as a reference surface when simultaneously finishing the outer peripheral surface of the support shaft is provided. Toroidal-type continuously variable transmission.   The toroidal continuously variable transmission according to claim 1, wherein the stepped portion is provided on the outer peripheral edge of the outer surface of each outer ring over the entire circumference.   The toroidal continuously variable transmission according to claim 2, wherein a positioning recess for positioning the chuck in the circumferential direction is provided on an outer surface of each outer ring.   The said level | step-difference part is any one of the Claims 1-2 provided in the axial direction of the said support beam part in the width direction both-sides part which pinches | interposes the said recessed part among the outer peripheral surface outer peripheral parts of each said outer ring | wheel. The toroidal type continuously variable transmission described in the item.   When each trunnion swings and displaces up to a permissible limit around the two tilting axes, each trunnion swings and displaces further on the basis of this engagement at the position where the step portion of each outer ring engages. The toroidal type continuously variable transmission according to any one of claims 1 to 4, further comprising a stopper that prevents the operation. Comprising at least one pair of disks, a plurality of trunnions, the same number of power rollers as each trunnion, and the same number of thrust rolling bearings;
Each of these disks is supported to be capable of relative rotation concentrically with each other in a state in which each side surface in the axial direction is a toroidal curved surface having an arc cross section.
Each trunnion exists between a pair of tilting shafts provided concentrically with each other at both ends, and between the two tilting shafts, and at least the inner side surface in the radial direction of each of the disks, A support beam portion having a cylindrical convex surface, having a central axis that is parallel to the central axis of both tilting axes and that is present outside the central axes of these two tilting axes with respect to the radial direction of each disk. Oscillating displacement about the respective tilting shafts at twisted positions with respect to the central axis of each disk at a plurality of locations in the circumferential direction between the axial side surfaces of the respective disks with respect to the axial direction. It is provided freely,
Each of the power rollers is rotatably supported on the inner side surface of each trunnion via a thrust rolling bearing, and each circumferential surface having a spherical convex surface is brought into contact with one axial side surface of each disk. And
Each thrust rolling bearing is provided between the support beam portion of each trunnion and the outer surface of each power roller, and an outer ring provided on each support beam portion side, and an inner ring of each outer ring. A plurality of rolling elements each provided in a freely rollable manner between an outer ring raceway provided on a side surface and an inner ring raceway provided on an outer side surface of each power roller;
The outer ring of each of the thrust rolling bearings rotatably supports each of the power rollers via a radial rolling bearing around a support shaft fixed to the center of the inner surface of each of the outer rings. By engaging the concave portion provided on the outer side surface and the cylindrical convex surface of each of the support beam portions, the trunnion is supported so as to be capable of swinging displacement in the axial direction of each disk, and Formed on the inner surface of the concave portion in the circumferential direction centering on the support beam portion, a concave groove which is a tapered groove having a wide opening and a narrow bottom portion, and an outer peripheral surface of the support beam portion, In the manufacturing method of the toroidal type continuously variable transmission in which the axial displacement of the support beam portion is limited by engaging with a projecting ridge which is a tapered ridge having a wide width and a narrow tip. And
A step portion is provided on at least a part of the outer peripheral edge of the outer surface of each outer ring, and each outer ring is gripped by a chuck in a state where the step portion is positioned as a reference surface, and the recess, the groove, and the outer ring A method for manufacturing a toroidal continuously variable transmission, characterized in that finishing is simultaneously performed on the track and the outer peripheral surface of the support shaft.
  The manufacturing method of the toroidal type continuously variable transmission according to claim 6, wherein the stepped portion is provided on the outer peripheral edge portion of the outer surface of each outer ring over the entire circumference.   The manufacturing method of the toroidal type continuously variable transmission according to claim 7, wherein a positioning recess for positioning the chuck in the circumferential direction is provided on an outer surface of each outer ring.   The said level | step-difference part is provided in any one of Claims 6-7 provided in the axial direction of the said support beam part in the width direction both-sides part which pinches | interposes the said recessed part among the outer peripheral surfaces outer peripheral parts of each said outer ring | wheel. Method for manufacturing a toroidal continuously variable transmission.

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