JP3374751B2 - Toroidal type continuously variable transmission - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a friction roller disposed between an input disk and an output disk, and changing the state of the friction roller to change the input state. The present invention relates to a toroidal type continuously variable transmission capable of changing a speed ratio between outputs. 2. Description of the Related Art As a conventional toroidal type continuously variable transmission, for example, Japanese Unexamined Patent Publication No. 10-262 has been proposed by the present applicant.
No. 01 is disclosed. In this toroidal-type continuously variable transmission, an input disk rotatable integrally with a torque transmitting rotary shaft and a rotatable output disk arranged coaxially around the torque transmitting rotary shaft are opposed to each other. A friction roller called a power roller is provided in a toroidal groove formed between the opposing surfaces of the input disk and the output disk, and the friction roller is supported so as to be able to tilt a supporter member called a trunnion. On the other hand, the support member is driven by the fluid pressure cylinder in a direction perpendicular to the axial direction of the friction roller and perpendicular to the axial direction of the input / output disk, that is, in the axial direction of the support member. Here, for example, if the axis of the friction roller and the axis of the input / output disk are displaced, a deviation occurs between the rotation direction of the friction roller and the input direction from the input disk, and the component of the deviation causes the friction roller to tilt. As a result, the contact radius between the friction roller that is in frictional contact with both disks and the input disk and the contact radius with the output disk change, so that the speed ratio between input and output changes. Here, for example, when the friction rollers are arranged symmetrically with respect to the axis of the torque transmitting rotary shaft, the pairs of friction rollers must be tilted in directions opposite to each other.
The support members that individually support them are driven in opposite directions. Further, since the friction roller and the input disk and the output disk must always be in frictional contact, the tilting state of the friction roller and the driving state of the support member must be completely synchronized. So, conventionally,
The upper and lower ends of the support member actually supporting the friction roller are connected by link members, and the link member is swingably connected to the case member, thereby synchronizing the support member and the friction roller. Like that. [0004] A connecting structure for connecting the link member so that the case member can swing is disclosed in, for example, Japanese Patent Application Laid-Open No. 9-291997 previously proposed by the present applicant. This prior art is for connecting a link member connecting lower end portions of the support members to a case member. This link member is common to the two toroidal transmission mechanisms provided inside the toroidal-type continuously variable transmission, and is swingably connected to the case member for each lower portion of each toroidal transmission mechanism. In this conventional technique, for each connection portion, the link member is connected to a base constituting a part of the case member by a swing shaft, and four stud bolts are implanted in the base, and the stud bolt is used. The nut is inserted into the case member and a nut is screwed into the male screw portion so as to be tightened. Further, as another aspect, for each connection portion, the link member is connected to a base by a swing shaft,
Four bolts with heads are inserted into the case member, and the male screw portions thereof are screwed to the female screw portions of the base to tighten them. In these prior arts, there is an advantage that when connecting the link member connecting the lower end portions of the support members to the case member, the heads of the nuts and bolts can be tightened from below the case member. Further, when the stud bolt is implanted, there is an advantage that the stud bolt serves as a guide when connecting the base to the case member. However, in the conventional link member connecting structure, four stud bolts and four nuts or four head bolts are provided for each connecting portion to the case member. Must use one of
In each case, the number of parts is large. When stud bolts are implanted, it takes time to implant the stud bolts. The present invention has been developed in view of these problems, and has a structure in which a link member is connected to a case member using only a press-fit bolt, a nut, and a headed bolt. Accordingly, it is an object of the present invention to provide a toroidal-type continuously variable transmission that can reduce the number of parts and the time and labor for embedding stud bolts while maintaining the guideability during assembly. In order to solve the above-mentioned problems, a toroidal type continuously variable transmission according to the present invention comprises a plurality of rotatable input disks and a plurality of output disks which are disposed between opposing rotatable input disks and output disks. Friction rollers, support members for individually supporting the friction rollers in a tiltable manner, fluid pressure cylinders for driving the support members in the axial direction to tilt the friction rollers, and both ends of each support member And a base for swingably supporting the link member in accordance with the driving of the support member in the axial direction. A press-fit bolt press-fitted into the base and a base member inserted therethrough. The base is attached to the case member by a nut screwed into the press-fit bolt and tightened, and a bolt with a head inserted through the case member from the nut side and screwed into the base to tighten. It is a sign. Thus, according to the toroidal type continuously variable transmission of the present invention, both ends of the support member supporting the friction roller are connected by the link member, and the support member is moved in the axial direction. so swingable in the driving direction, with connecting the link member to the base, and the nut nuts to it by inserting the indented pressed bolts to the base case member screwed fastening so that screwing Since the headed bolt is inserted into the case member from the set side and screwed to the base to tighten, the base is attached to the case member and the link member is swingably connected to the case member. It is possible to reduce the number of parts to be performed, and it is possible to obtain guideability at the time of assembling by press-fitting bolts press-fitted in advance,
In addition, labor for embedding stud bolts is reduced. An embodiment of a toroidal-type continuously variable transmission according to the present invention will be described below with reference to the accompanying drawings. First, a schematic configuration of the toroidal type continuously variable transmission according to the present embodiment will be briefly described in order from the input side to the output side with reference to FIG. The rotational force of an engine (not shown) is input to an input shaft 2 via a torque converter 4 in a transmission case 1. This input shaft 2
The power transmission rotary shaft 3 is coaxially disposed on the right side in the figure. An oil pump 5 is mounted on the input shaft 2, and a forward clutch mechanism for switching an input rotation direction to the rotary shaft 3 by switching a fixed element of a planetary gear mechanism 8 is provided on the right side of the oil pump 5 in the drawing. A forward / reverse switching mechanism 9 provided with a reverse brake mechanism 6 and a reverse brake mechanism 7 is provided. Further, the rotary shaft 3 is provided with two toroidal cavities, that is, first and second toroidal transmission mechanisms 10 and 11 which form a groove, and are disposed apart from each other in the axial direction. A sun gear 13 rotatably supported by the input shaft 2 via a needle bearing 12 and constituting a planetary gear mechanism 8 of the forward / reverse switching mechanism 9 between the input shaft 2 and the rotary shaft 3; A loading cam 14 engaged with a claw portion 13a formed on the sun gear 13 and rotatably supported by the rotating shaft 3;
Input disk 1 connected to the rotary shaft 3 via an engagement roller 15 and supported on the rotating shaft 3 via a ball spline 16.
7 are interposed. The engaging roller 15 is rotatably held by a holder 41. Therefore, the torque transmitted from the engine to the input shaft 2 is transmitted to the loading cam 14, the engagement roller 15, the input disk 17, and the ball spline 16 from the claw portion 13a of the sun gear 13 via the forward / reverse switching mechanism 9. The rotation is transmitted to the rotating shaft 3 via the control shaft . When the engaging roller 15 moves along the leads of these cam surfaces, a thrust force in the axial direction of the torque transmitting rotary shaft 3 proportional to the input torque, that is, a thrust force is generated. ing. Further, between the loading cam 14 as the input cam and the input disk 17 as the output cam, a disc spring 42 for applying a force in a direction for separating the two and applying a preload is interposed. . The loading cam 14 and the input disk 1
By supplying a predetermined oil pressure between the thrust force and the thrust force in the axial direction, that is, the thrust force can be adjusted. The loading cam 14 is rotatably supported on the rotating shaft 3 by a ball bearing 44. The first toroidal transmission mechanism 10 includes an input disk 17 having a toroidal surface 17a formed on a surface away from the engagement roller 15;
A toroidal surface 18a is formed on the opposing surface of the input disk 17, an output disk 18 rotatably supported by the rotating shaft 3 and constituting a first cavity by the two toroidal surfaces, a toroidal surface 17a of the input disk 17 and an output disk. And a power roller (friction roller) 29 that tiltably contacts a groove formed by the toroidal surface 18a of the motor 18. The power roller 29 is tiltably supported by a support mechanism described below called a trunnion, and by operating this trunnion with a fluid pressure cylinder described later,
The radial contact position between the power roller 29 and the input disk 17 and the output disk 18 can be changed, so that the rotational speed ratio between the input disk 17 and the output disk 18 can be continuously changed. ing. The second toroidal transmission mechanism 11
Has an input disk 19, an output disk 20, a power roller (friction roller) 30, a support mechanism, and a fluid pressure driving device, like the first toroidal transmission mechanism 10. The output disks 18, 2 opposed to each other
An output gear 22 is disposed between the rear surfaces of the output disks 22. The output gear 22 has cylindrical shaft portions 18b and 20b protruding in the axial direction from both ends of the central portion of the output gear 22. Splined with them. The output gear 22 is rotatably supported by a gear housing 23 fixed to the inner peripheral wall of the transmission case 1 via a bearing 24. The output gear 22 meshes with a counter gear 25, and the counter gear 25 is rotatably supported by the gear housing 23 via a bearing 26. Further, one end of a counter shaft 27 is spline-coupled to the center of the counter gear 25, and the other end of the counter shaft 27 is rotatably supported by the transmission case 1 via the bearing 21 , so that both ends are supported. Are designed to rotate together. Therefore, the torque transmitted from the engine to the rotating shaft 3 is applied to the first and second toroidal transmission mechanisms 10,
And the output disks 18 of the toroidal transmission mechanisms 10 and 11 at a predetermined speed ratio by the tilting operation of the power rollers 29 and 30 described above.
After being transmitted to the output gear 20, it is synthesized by the output gear 22 and transmitted to the output shaft 33 via the counter gear 25, the counter shaft 27 and the gear train 28 in that order. Next, shift control by each of the toroidal shift mechanisms will be briefly described. FIG. 2 shows a longitudinal section of the center of the cavity of the first toroidal transmission mechanism 10 facing the rear of the vehicle as a representative thereof. Two power rollers 2 9 facing in the drawing, between the output disks 1-8 and the placed on the axis O ₁ in the figure the first toroidal transmission mechanism 1 0 of the input disk (not shown) The power rollers 2 are arranged so as to be able to transmit rotational power.
9, trunnion 46F L each right in the figure, with is rotatably supported via the eccentric shaft 47 to the trunnion 46F R shown left, they trunnions 46FL, 46
The upper end of the FR is the upper link 5 of the upper link mechanism 34.
The lower link is connected via a lower link 52 of the lower link mechanism 35. [0017] Among trunnion 46F L shown right rotatably supporting the power rollers 2 9, the illustrated neutral position of the power roller rotation axis O ₂ intersect the input and output disks rotation axis O ₁ From the power roller rotation axis O
As an offset in the direction of the oscillation axis O ₃ that is perpendicular to the _2, displaced in the direction of the oscillation axis O _3, and and and can tilt around a swing axis O _3. [0018] Then, the bottom of the trunnion 46F L of the lower link 52 is connected, trunnion shaft 7
The upper end of the trunnion shaft 70 is bar-coupled via a pin 56. The piston boss portion 78a of the piston 78FL of the fluid pressure cylinder 77 is externally fitted to the trunnion shaft 70, and is connected to a male screw formed at the lower end of the trunnion shaft 70. , Nut 8
By tightening the 2 screwed with the piston boss 78a, the piston 78F L is integrated in the trunnion 46F L via a trunnion shaft 70. Also,
Cylinder body 6 which houses the piston 78F L
0, the piston 78F L by Ri and defining a first fluid chamber 90a to the nut 82 side piston 78F L by Ri trunnion 4
A second fluid chamber 90b is defined on the 6FL side , and the working fluid pressure generated by the shift control valve based on the commanded gear ratio is supplied. Then, the first and second fluid chambers 90a, 9
Depending on the pressure difference 0b the piston 78F L is swing axis O ₃
Displaced by a predetermined amount in direction, the displacement of the piston 78F L, trunnion 46F L input and output discs 17, 1
8 to swing axis O ₃ direction displaces (offset) for, this offset power rollers 2 9 changes the tilting angle in the direction corresponding to the shift command. The upper end of the trunnion shaft 70 is also bar-coupled via a pin 56 to the lower part of the trunnion 46FR on the left side of the figure, which rotatably supports the power roller 29. 70, the piston boss portion 78 of the piston 78FR of the fluid pressure cylinder 77
a and precess cam 66 is externally fitted, by tightening the piston boss portion 78a and the precess cam 66 is screwed to a nut 82 to the male screw formed at the lower end of the trunnion shaft 70, the piston 78F R is the trunnion shaft 70
It is integrated in the trunnion 46F R through. Further, the piston 78F housing the R and the cylinder body 60, first the first fluid chamber 92a in image form and piston 78F R by Ri nut 82 side Ri by the piston 78F R trunnion 46F R side <br/> A two-fluid chamber 92b is defined, and the working fluid pressure generated by the shift control valve is supplied to each. The first and second fluid chambers 92a, piston 78F R is displaced by a predetermined amount in swing axis O ₃ direction according to the pressure difference 92b, by the displacement of the piston 78F R, input and output disks trunnion 46F R 17,1 8 swing axis in the O ₃ direction displaces (offset) for, this offset Pawarora 2 9 changes the tilting angle in the direction corresponding to the shift command. Here, the precess cam 66 is provided only in the first toroidal transmission mechanism 10. The precess cam 66, the is swivel axis O ₃ guide groove 66a which is inclined direction is formed, and the guide groove 66a, the power rollers 29 and 30 engaged with the end of the shift link 68 is engaged
Although the displacement (offset amount and tilt amount) of the transmission link is fed back to the transmission control valve , the transmission link 68 is engaged with the transmission link 68 so that the upper surface of the end of the transmission link 68 always contacts the guide groove 66a. From the mating spring member (not shown), the swing axis O ₃
An upward urging force (reference numeral Fa in FIG. 2) acts on the piston 78FR. [0021] Then, during normal forward travel of driving the engine, by increasing the fluid pressure in the first fluid chamber 90a, 90a of the respective hydraulic cylinder 77 by the supply pressure of the shift control valve or al, relatively the When the fluid pressure in the two fluid chambers 90b and 92b is reduced to generate a pressure difference between the two fluid chambers, the piston 78FL
~78RR to stroke the solid line arrow S _U along the swing axis O ₃ directions. Thereby, the power roller 29 _,
The axis O _{2 of} 30 and the axis O _{1 of the} input / output disk are shifted,
As a result, for example, a deviation occurs between the rotation direction of the power rollers 29, 30 and the input direction from the input disks 17, 19, and the component of the deviation causes the power rollers 29, 30 to move the trunnions 46FL to 46RR along the swing axis. O ₃ is tilted around the center, thereby the power rollers 29 _and 30 are tilted.
And input disks 17, 19 and output disks 18, 20
In this case, the speed ratio between the input and output changes, and in this case, the vehicle speed reduction ratio is reduced, that is, the speed ratio is changed to the high side to upshift. Conversely, when the fluid pressure in the first fluid chambers 90a, 90a of each fluid pressure cylinder 77 is lowered, and the fluid pressure in the second fluid chambers 90b, 92b is relatively increased to generate a pressure difference between them, Piston 78FL ~
78RR strokes in the direction of the dashed arrow _SD, and as a result, the power rollers 29 and 30 tilt in the opposite direction to the above, and in this case, the direction in which the vehicle reduction ratio increases, that is, the gear ratio is changed to the low side. Downshift. The tilting direction of the power rollers 29, 30 and the direction of displacement of the trunnions 46FL-46RR are completely opposite between the pair of power rollers 29, 30 sandwiching the rotary shaft 3, and the balance is adjusted by the upper link device. 34 and the lower link device 35. Further, as described above, the input disk 1 of the first toroidal transmission mechanism 10 is used.
7 and the input disk 19 of the second toroidal transmission mechanism 11 rotate synchronously with the rotating shaft 3 and the output disk 18 of the first toroidal transmission mechanism 10 and the second toroidal transmission mechanism 1
Since the first output disk 20 is connected to the output gear 22 by the output gear 22, the tilting of the power rollers 29, 30 of each of the toroidal transmission mechanisms 10, 11 must be tilted completely synchronously. Therefore, the supply of the working fluid pressure to each of the above-described fluid pressure cylinders is simultaneously performed from the fluid pressure control valve via a servo mechanism (not shown). The upper link device 34 and the lower link device 35 are, for example, connected to the transmission case 1 (strictly, connected thereto) at respective portions of the cavity of the first toroidal transmission mechanism 10 and the cavity of the second toroidal transmission mechanism 11. The upper link 50 and the lower link 5 of each link device are connected to each other.
2 is a continuum common to each other. That is, for example, FIG.
As shown in FIG. 1, the first and second toroidal transmission mechanisms 10,
This is a plate-like body in which holes 57 are formed in portions corresponding to the output disks 18 and 20 and the output gear 22 to prevent interference. The upper link 50 and the lower link 52
Connects the upper and lower ends of the trunnions 46FL to 46RR so as to swing and rotate via a spherical joint 51 with roller bearings, respectively. Further, the upper link 50 and the lower link 52 are connected to each toroidal transmission mechanism 1.
At each of the upper and lower portions of 0,11, the rotating shaft 3
Through the pivot shaft 54 and 55 with the axis O axis parallel to _1, respectively, by connecting to the transmission case (member) 1, the operating state of the trunnion 46FL~46RR and power rollers 29 and 30 synchronously Take. Of these, trunnions 46FL-46RR
The lower link 52 connecting the lower end portions of the first and second toroidal transmission mechanisms 10 and 11 is, for example, as shown in FIG.
Are connected to the case member 1a using a connection structure as shown in FIG. Actually, the lower part of the first toroidal transmission mechanism 10 and the lower part of the second toroidal transmission mechanism 11
Although the lengths of the bolts used are different, the basic connection structure is the same. That is, the lower link 52 is connected to the case member 1.
The lower link 52 is thick at a portion connected to a, and a through hole 58 for inserting the swing shaft 55 is formed in the thick portion 52a. A hole 61 for accommodating a base 59 (to be a part of the case member 1a) described later is formed in the center of the thick portion 52a of the lower link 52. The base portion 59 is a flat plate that is housed in a hole 61 formed in the thick portion 52a of the lower link 52. The swing shaft 55 is inserted through the central thick portion 59a. Are formed. Of the flat portions on both sides of the central thick portion 59a of the base portion 59, a through hole 81 is formed in one flat portion 59b, and a female screw 83 is formed in the other flat portion 59c. The press-fit portion 84a of the press-fit bolt 84 is press-fitted into the through hole 81 downward in the drawing, that is, toward the case member 1a.
Therefore, the male screw 84b of the press-fit bolt 84 protrudes from the one flat plate portion 59b of the base 59 toward the case member 1a. On the other hand, the case member 1a which is a part of the transmission case 1 is provided with a storage portion 1c for tightly storing the base portion 59. When the base portion 59 is stored in the storage portion 1c, the press-fitting bolt is formed. 84 male screw 84
A through hole 85 is formed in a portion corresponding to b. Further, a through hole 86 is formed in a portion of the base 59 corresponding to the female screw 83. In this connection structure, the base 59 is housed in the hole 61 of the lower link 52 with the press-fit bolt 84 being press-fitted in the base 59 in advance, and the lower link 5
The rocking shaft 55 is inserted from one of the through holes 58 formed in the thick portion 52a through the through hole 80 of the base 59, and in this state, the male screw 84b of the press-fitting bolt 84 is inserted into the through hole 85. The base portion 59 is stored in the storage portion 1c of the case member 1a so that the base portion 59 is inserted. Then, the male screw 84b of the press-fit bolt 84 press-fitted into the base portion 59 projects downward from the case member 1a in the figure, so that the male screw 84b
A nut 87 is screwed into the nut and tightened.
The headed bolt 88 is inserted through the through hole 86 of the case member 1a from the side, and is inserted into the female screw 8 of the base 59.
Screw into 3 and tighten. The first toroidal transmission mechanism 10
And the lower part of the second toroidal transmission mechanism 11 are performed.
Except for the components used, the base 59, the press-fit bolt 8
4, nuts 87, and headed bolts 88 are required, so that the number of parts can be reduced, and there is no need to embed stud bolts as in the related art. Also, the base 59
Since the male screw 84b of the press-fit bolt 84 protrudes from above, the use of this as a guide improves the assembling workability.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal sectional view showing an example of a toroidal type continuously variable transmission. FIG. 2 is a vertical sectional view showing a first toroidal transmission mechanism of FIG. 1; FIG. 3 is a perspective view showing one embodiment of a lower link connection structure used in the toroidal type continuously variable transmission shown in FIG. 1; DESCRIPTION OF THE SYMBOLS 1 is a transmission case 1a is a case member 10 is a first toroidal speed change mechanism 11 is a second toroidal speed change mechanism 17, 19 is an input disk 18, 20 is an output disk 29, and 30 is a power roller (friction roller) 46FL. 46RR is a trunnion (support member) 52 is a lower link (link member) 55 is a swing shaft 59, a base 77, a fluid pressure cylinder 81, a through hole 83, a female screw 84, a press-fit bolt 87, a nut 88, and a head bolt.

Claims (1)

(57) Claims 1. A plurality of friction rollers disposed between opposed rotatable input disks and output disks, and supports for individually supporting these friction rollers in a tiltable manner. Components,
A fluid pressure cylinder that drives the support member in the axial direction to tilt the friction roller, a link member that connects each end of each support member, and a link member that moves the support member in the axial direction. A base for swingably supporting the drive, a press-fit bolt press-fitted into the base, a nut screwed into the press-fit bolt inserted into the case member and tightened, and a case member inserted from the nut side A toroidal-type continuously variable transmission, wherein the base is attached to a case member by a headed bolt that is screwed into the base and tightened.