JP2007211880A - Toroidal-type stepless transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To secure a lubrication of a disc spring even if a displacement of an input disc increases while preventing the coherence of the disc spring for pre-load generation by regulating the displacement of an input disc in the pre-loading mechanism of a toroidal type stepless transmission. <P>SOLUTION: The pre-loading mechanism 16 comprises a spacer 22 arranged by separation only at a distance shorter than the largest compression quantity of the belleville springs 21a, 21b from the input disc 1b radially outside of the belleville springs 21a, 21b, and a collar 25 interposed between a step formed in the outer periphery of the input shaft 20 and a loading nut 23 and arranged by separation from the input disc 1b, and is so constituted that the lubricating oil from lubricating oil supply routes 9a, 9b can be supplied to the belleville springs 21a, 21b through the clearance among a ball bearing 13 of the input disc 1b, the input disc 1b, and the collar 25. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a toroidal continuously variable transmission, and more particularly to the structure of a preloading mechanism.

  In the toroidal continuously variable transmission, it is necessary to apply a thrust load to the input / output disk in order to sandwich the power roller between the input / output disk. In general, a thrust load proportional to the torque input to the transmission is generated by a loading cam and applied to the input / output disk.

In addition, when the torque input to the transmission is zero, the loading cam does not generate a thrust load. Therefore, it is necessary to provide a preloading mechanism separately from the loading cam and apply a predetermined preload (preload) to the input / output disk. In the toroidal-type continuously variable transmission described in Patent Document 1, as shown in FIG. 7, the preloading mechanism is constituted by two disc springs provided on the back surface of the input disk.
JP 2000-74167 A

  The axial position of the input disc varies depending on the transmission gear ratio (tilt angle of the power roller) and the input torque. However, when the disc spring is pressed against the input disc and the disc springs are brought into close contact with each other, a large force is exerted on the contact surface. Acts and the disc spring is worn out. Since the wear of the disc spring causes a decrease in the preload, the conventional technology described above prevents the disc springs from coming into close contact with each other by interposing a spacer that regulates the displacement of the input disc between the input disc and the loading nut. It is out.

  However, in this configuration, since the spacer is disposed radially inward of the disc spring, the lubricating oil from the input disk bearing portion is difficult to reach the disc spring, and the input disc is displaced and closely contacts the spacer. In this case, the lubricating oil from the bearing portion of the input disk is not supplied to the disc spring, and there is a possibility that the disc spring may be worn due to lack of lubricating oil.

  The present invention has been made in view of such technical problems, and is a case where the displacement of the input disk is restricted to prevent the disc springs from coming into close contact with each other, and the displacement of the input disk becomes large. Another object is to ensure the lubrication of the disc spring.

  A toroidal continuously variable transmission according to the present invention includes a fixing member fixed at a predetermined axial position of a shaft that supports an input / output disk, and a fixed member disposed between the fixing member and the input disk. Formed on the outer periphery of the shaft, a displacement regulating member disposed on the outer side in the radial direction of the elastic member, spaced from the input disk by a distance shorter than the maximum compression amount of the elastic member, And a preload adjusting member disposed between the stepped portion and the fixed member and spaced apart from the input disk, and the lubricating oil from the lubricating oil supply passage is adjusted to the bearing portion of the input disk, the input disk and the preload adjusting member. The elastic member is supplied through a gap between the members.

  According to the present invention, the displacement restricting member that restricts the axial displacement of the input disk is disposed radially outside the elastic member that imparts the preload, and the preload adjusting member is disposed away from the input disk. Thus, even when the displacement of the input disk increases, the elastic member can be prevented from being compressed to the maximum compression amount, and the supply of lubricating oil to the elastic member can be ensured, and the elastic member is worn. There is an effect that can be suppressed.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

  FIG. 1 shows a configuration of a toroidal continuously variable transmission according to the present invention, and the left side in the figure is connected to an engine via a torque converter (not shown).

  The toroidal continuously variable transmission has a so-called double cavity configuration in which a first toroidal unit 11 and a second toroidal unit 12 are arranged in series. The first toroidal unit 11 has a pair of power rollers 3 sandwiched between an input disk 1a and an output disk 2a. Similarly, the second toroidal unit 12 has a pair of power rollers 3 sandwiched between the input disk 1b and the output disk 2b. The input disks 1a and 1b are supported on the input shaft 20 (shaft) via ball splines 13 (bearing portions) and rotate in synchronization. Lubricating oil is supplied to the ball spline 13 via lubricating oil supply passages 9 a and 9 b formed inside the input shaft 20.

  The output disks 2a and 2b are coupled via an output gear 10, and the output rotation of the transmission is transmitted from the output gear 10 to a drive shaft (not shown). The input shaft 20 passes through the output gear 10, and the output disks 2 a and 2 b rotate relative to the input shaft 20.

  Each power roller 3 is supported by a trunnion 4. When a hydraulic actuator (not shown) displaces each trunnion 4 in the vertical direction in the figure, each power roller 3 is tilted, the contact radius with the input / output disk is changed, and the gear ratio is continuously changed. . The trunnions 4 facing each other are connected by an upper link 5 at the upper end and a lower link 6 at the lower end, and are displaced in opposite directions.

  The oil film between the input / output disks 1a, 1b, 2a and 2b and the power roller 3 becomes glassy under high pressure, and the driving force is transmitted by the shear force of the oil film. On the left side of the input disk 1a in the figure, there is provided a loading cam 8 that generates a thrust load corresponding to the input torque and applies it to the input / output disks 1a, 2a, 1b, and 2b.

  On the other hand, on the right side of the input disk 1b in the figure, a preload that gives the preload (preload) necessary for clamping the power roller 3 to the input / output disks 1a, 2a, 1b, and 2b even when the input torque is small or zero. A mechanism 16 is provided.

  As shown in FIG. 2, the preloading mechanism 16 has a pair of disc springs 21a and 21b (elastic members) disposed on the back surface of the input disk 1b and an outer periphery from the side of the disc springs 21a and 21b so as to cover the disc springs. A spacer 22 (displacement restricting member) arranged so as to extend toward the side and a screw portion formed at the end of the input shaft 20 are screwed together, and the disc springs 21a and 21b are connected to the input disk 1b via the spacer 22. A loading nut 23 (fixing member) pressed against the back surface of the input shaft and a preload adjusting collar 25 (preload adjusting member) interposed between the loading nut 23 and a stepped portion 24 formed on the outer periphery of the input shaft 20. Is done.

  An annular concave portion 29 is formed on the inner peripheral side of the back surface of the input disk 1b, and a chamfered portion 25r is formed on a portion of the collar 25 on the radially outer side on the input disk side and facing the concave portion 29. Thus, a gap for supplying lubricating oil is formed between the input disk 1b and the collar 25.

  The spacer 22 is an annular member having a substantially L-shaped cross section, and has a disc part 22a (presser part) having an opening through which the tip of the loading nut 23 is inserted at the center, and disc springs 21a and 21b of the disc part 22a. It is comprised by the cylinder part 22b (cylindrical displacement control part) extended substantially perpendicularly toward the input disk 1b from the position of a radial direction outer side. The disk portion 22a is sandwiched between a flange portion 23f formed in the axial direction of the loading nut 23 and the collar 25, whereby the spacer 22 is fixed at a predetermined position in the axial direction. Moreover, the inner wall of the cylinder part 22b contacts the outer periphery of the disc springs 21a and 21b, and thereby the disc springs 21a and 21b are positioned in the radial direction.

  The disc springs 21a and 21b are arranged in a state in which they are in contact with each other at the outer peripheral edge portion in the radial direction and a gap (disc spring gap) X formed between the two is directed radially inward. The lubricating oil supplied to the ball spline 13 from the lubricating oil supply passages 9a and 9b is directly supplied to the disc springs 21a and 21b through the gap between the input disk 1b and the collar 25, whereby the disc spring 21a. , 21b is lubricated. Lubricating oil supplied to the disc springs 21a and 21b is held in the oil chamber 27 defined by the back surface of the input disk 1b, the spacer 22 and the collar 25, and the amount of lubricating oil supplied to the disc springs 21a and 21b. Even if it decreases, the good lubricating state of the disc springs 21a and 21b is maintained.

  The preloading of the preloading mechanism 16 is adjusted by adjusting the axial length Y of the collar 25 and adjusting the distance between the back surface of the input disk 1b and the loading nut 23 and the spacer 22. That is, if the axial length Y of the collar 25 is shortened, the screwing amount of the loading nut 23 is increased accordingly, the loading nut 23 and the spacer 22 are brought closer to the input disk 1b, and the compression amount of the disc springs 21a and 21b is increased. Preload increases. Conversely, to reduce the preload, the axial length Y of the collar 25 may be increased. When assembling the transmission, several collars 25 having different axial lengths are prepared, and the collar 25 capable of obtaining a predetermined preload is selected.

  Here, the axial length of the cylindrical portion 22b is such that the distance Z between the input disk side end of the cylindrical portion 22b and the back surface of the input disk 1b when the input torque of the transmission is zero is allowed for the disc springs 21a and 21b. Is set to be smaller than the maximum compression amount (for example, the distance X between the disc springs 21a and 21b when the input torque is zero). Thus, even if the input disk 1b is greatly displaced in the axial direction according to the transmission gear ratio and input torque, the end of the cylindrical portion 22b is placed on the back surface of the input disk 1b before the disc springs 21a and 21b come into close contact with each other. Can be prevented, and the disc springs 21a and 21b can be prevented from coming into close contact with each other.

  Further, since the cylindrical portion 22b abuts on and supports the input disk 1b at a radially outer position where the deformation amount of the input disk 1b increases, the deformation of the input disk 1b can be suppressed, and the input disk 1b is made conventional. It can be made thinner. In addition, the contact ellipse between the power roller and the disk is less likely to drop off from the traction surface, and there is an advantage that the available gear ratio range can be increased.

  Further, even if the cylindrical portion 22b comes into contact with the back surface of the input disk 1b and comes into close contact with the input disk 1b, this occurs on the outer side in the radial direction than the disc springs 21a and 21b, and the concave portion 29 and the collar formed on the input disk 1b. Since there is a gap for supplying lubricating oil between the input disk 1b and the collar 25 due to the chamfered portion 25r formed in 25, the flow of lubricating oil from the ball bearing 13 to the disc springs 21a and 21b Thus, good lubrication of the disc springs 21a and 21b can be ensured.

  The lubricating oil supplied to the oil chamber 27 is mainly used for lubricating the disc springs 21a and 21b. However, the amount of lubricating oil supplied to the oil chamber 27 is increased to increase the hydraulic pressure in the oil chamber 27. Then, the back surface of the input disk 1b may be supported by this hydraulic pressure to further suppress the deformation of the input disk 1b.

  FIG. 3 shows a second embodiment of the present invention.

  In the second embodiment, an annular groove 30 is formed at a position facing the input disk side end portion of the cylindrical portion 22b of the spacer 22 on the back surface of the input disk 1b, and the annular groove 30 is formed on the input disk side of the cylindrical portion 22b. The point from which the edge part penetrated differs from 1st Embodiment.

  The distance between the bottom surface of the annular groove 30 and the end of the cylindrical part 22b on the input disk side corresponds to the distance Z in the first embodiment, and the gap between the side wall of the annular groove 30 and the cylindrical part 22b, that is, the radial gap is The end of the cylindrical portion 22b on the input disk side is set smaller than the interval Z to the extent that it does not become a resistance when moving in the annular groove 30. As a result, the lubricating oil retained in the oil chamber 27 is prevented from flowing out from the gap between the bottom surface of the annular groove 30 and the end of the cylindrical portion 22b on the input disk side.

  In the second embodiment, such a configuration makes it easier for the lubricating oil to be held in the oil chamber 27 than in the first embodiment, and further improves the lubricating state of the disc springs 21a and 21b. Can do. This configuration is also advantageous when the oil pressure in the oil chamber 27 is increased to support the back surface of the input disk 1b.

  4 and 5 show the third and fourth embodiments of the present invention. In the first embodiment, the spacer 22, the loading nut 23, and the collar 25 are configured as separate members, but in the third embodiment, the spacer 22 and the collar 25 are formed integrally, and in the fourth embodiment, the spacer The point which integrally formed 22 and the loading nut 23 differs from 1st Embodiment, respectively. By adopting such a configuration, the number of parts of the transmission can be reduced and the assembly workability can be improved.

  FIG. 6 shows a fifth embodiment of the present invention. The fifth embodiment is different from the first embodiment in that the disc springs 21a and 21b are brought into contact with each other in the radial direction and the gap X between the two is directed in the radial direction. By arranging the disc springs 21a and 21b in such a manner, the contact position between the disc springs 21a and 21b and the input disk 1b becomes closer to the peripheral edge of the disc springs 21a and 21b, that is, radially outward. Since the input disk 1b is supported at a radially outer position than the form, the deformation of the input disk 1b can be further suppressed.

  Although the embodiments of the present invention have been described above, the above embodiments only show some examples of configurations to which the present invention is applied, and the technical scope of the present invention is limited to the configurations of the above embodiments only. is not.

  The present invention can be variously modified without departing from the gist of the present invention. For example, the present invention is not limited to a double-cavity toroidal continuously variable transmission, but to a single-cavity continuously variable transmission. Is also applicable.

  In the above embodiment, the annular groove 30 is formed on the back surface of the input disk 1b (second embodiment), and the spacer 22 and the collar 25 are integrated (third embodiment). It is also possible to combine a plurality of embodiments within a compatible range, such as integrating the loading nut 30 (fourth embodiment).

It is sectional drawing of the toroidal type continuously variable transmission by this invention. It is sectional drawing of a preloading mechanism (1st Embodiment). Similarly, it is sectional drawing of a preloading mechanism (2nd Embodiment). Similarly, it is sectional drawing of a preloading mechanism (3rd Embodiment). Similarly, it is sectional drawing of a preloading mechanism (4th Embodiment). Similarly, it is sectional drawing of a preloading mechanism (5th Embodiment). It is sectional drawing of the conventional preloading mechanism.

Explanation of symbols

1a, 1b Input disk 2a, 2b Output disk 3 Power roller 8 Loading mechanism 9a, 9b Lubricating oil supply path 13 Ball spline (bearing part)
16 Preloading mechanism 20 Input shaft (shaft)
21a, 21b Disc spring (elastic member)
22 Spacer (Displacement restricting member)
22a Disk part (presser part)
22b Tube portion (tubular displacement regulating portion)
23 Loading nut (fixing member)
24 steps 25 color (preload adjustment member)
25r chamfered portion 29 recessed portion 30 annular groove

Claims (8)

An input disk, an output disk, a shaft that supports the input / output disk, a lubricating oil supply passage that supplies lubricating oil to a bearing portion of the input disk, and a pair of power rollers sandwiched between the input / output disks And a toroidal continuously variable transmission comprising a loading mechanism that generates a thrust load according to an input torque input to the transmission and applies the thrust load to the input / output disk.
A fixing member fixed at a predetermined axial position of the shaft;
An elastic member disposed between the fixing member and the input disk to give a predetermined preload to the input / output disk;
A displacement restricting member disposed on the outer side in the radial direction from the elastic member and spaced from the input disk by a distance shorter than the maximum compression amount of the elastic member;
A preload adjusting member that is interposed between a step formed on the outer periphery of the shaft and the fixing member, and is disposed apart from the input disk;
The lubricating oil from the lubricating oil supply path is supplied to the elastic member through a bearing portion of the input disk and a gap between the input disk and the preload adjusting member. Toroidal continuously variable transmission.   A recess is formed in the inner periphery of the input disc on the side of the displacement regulating member so that a gap is formed between the input disc and the preload adjusting member even when the input disc is displaced and is in contact with the displacement regulating member. The toroidal continuously variable transmission according to claim 1, wherein the toroidal continuously variable transmission is formed.   Even when the input disk is displaced and in contact with the displacement regulating member, a chamfer is formed on the radially outer side of the input disk side of the preload adjusting member so that a gap is formed between the input disk and the preload adjusting member. The toroidal continuously variable transmission according to claim 1 or 2, wherein a portion is formed.   The displacement restricting member includes a pressing portion that contacts the elastic member from the opposite side of the input disk, and a cylindrical displacement restricting portion that extends toward the input disk from a position radially outside the elastic member of the pressing portion. The toroidal continuously variable transmission according to any one of claims 1 to 3, wherein   The toroidal type non-blank according to claim 4, wherein an annular groove into which an end of the cylindrical displacement regulating portion on the input disk side enters is formed at a position facing the cylindrical displacement regulating portion of the input disk. Step transmission.   The toroidal continuously variable transmission according to any one of claims 1 to 5, wherein the preload adjusting member and the displacement regulating member are configured as a single member.   The toroidal continuously variable transmission according to any one of claims 1 to 5, wherein the displacement restricting member and the fixing member are formed of a single member.   The toroidal continuously variable transmission according to claim 1, wherein the elastic member and the input disk are in contact with each other at a position closer to a radially outer side of the elastic member.

Images