JPH0641004Y2 - Toroidal type continuously variable transmission - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] In this invention, a tiltable power roller is provided between an input disk and an output disk forming a toroidal space, and the tilt angle of the power roller is adjusted. By controlling, toroidal type continuously variable transmission that is capable of continuously variable transmission,
In particular, the present invention relates to a toroidal type continuously variable transmission that improves power transmission efficiency by a power roller.

[Conventional technology]

As a conventional toroidal type continuously variable transmission, for example,
Some are described in Japanese Patent Publication No. 62-128262.

In this conventional example, as shown in the enlarged view of the main part in FIG. 4, the power rollers 3a, 3b rollingly contacted between the input disc 1 and the output disc 2 are pivotally attached to the trunnions 4a, 4b which are tiltably supported. The input disk 1 is rotatably supported by the eccentric support shafts 5a and 5b which are eccentrically moved, and the input disk 1 is connected to an input shaft 6 connected to a rotary drive source such as an engine through a pressurizing mechanism 7. Have. Here, the power rollers 3a, 3b
Is composed of a bowl-shaped portion 3c that is in rolling contact with the input disc 1 and the output disc 2, and a steel receiving portion 3e that is received by the bowl-shaped portion 3c via a ball bearing 3d. The receiving portion 3e and the trunnion
Sliding bearings 8a, 8b are interposed between the surfaces facing 4a, 4b.

[Problems to be solved by the device]

However, in the above conventional toroidal type continuously variable transmission, since the slide bearing is interposed between the power roller and the trunnion, the friction coefficient between the slide bearing and the receiving portion of the power roller is large. When a sudden torque fluctuation occurs between the input disc and the output disc, the sliding frictional force of the power roller increases and the input disc 1
An unsolved problem that causes a delay in the pressing force transmitted by the pressurizing mechanism transmitted to the power rollers 3a and 3b through the output rollers and reduces the pressing force between the output disk and the power roller to cause slippage between them. was there.

Therefore, the present invention has been made by paying attention to the unsolved problem of the above-mentioned conventional example, and reduces the friction coefficient between the power roller and the trunnion to suppress the slip between the power roller and the output disk, thereby transmitting the power. An object of the present invention is to provide a toroidal type continuously variable transmission that can improve efficiency.

[Means for Solving the Problems]

In order to achieve the above object, the present invention provides a toroidal continuously variable transmission in which a power roller which is eccentrically movable in a trunnion and rotatably supported and tiltable is disposed between an input disk and an output disk. In the above, a rolling bearing is inserted between the facing surfaces of the power roller and the trunnion.

[Action]

In the present invention, the rolling bearing interposed between the facing surfaces of the power roller and the trunnion reduces the sliding frictional force of the power roller, and even if there is a sudden torque fluctuation between the input disk and the output disk, Maintains the pressing force between the output disc and the power roller,
The slip between them is suppressed, and the power transmission efficiency by the power roller is improved.

〔Example〕

 An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view showing an embodiment of the present invention, and FIG. 2 is a plan view of a rolling bearing.

In FIG. 1, 1 is an input disk, 2 is an output disk, and both disks 1 and 2 are concentrically opposed to each other so as to form a toroidal space therebetween. Both discs 1,
Between the two, the power rollers 3a and 3b are in rolling contact with each other at the upper and lower positions. The power rollers 3a and 3b are composed of a bowl-shaped portion 3c that is in rolling contact with both discs 1 and 2, and a steel receiving portion 3e that receives the bowl-shaped portion 3c via a ball bearing 3d. , 3b extend in a direction orthogonal to the central axes of both disks 1 and 2 and are eccentrically supported by trunnions 4a and 4b rotatably arranged about the central axis of the toroidal space as a fulcrum. The shafts 5a and 5b are rotatably supported while eccentrically moving.

On the other hand, the input disk 1 is connected to an input shaft 6 connected to a rotary drive source such as an engine via a pressurizing mechanism 7, and by the pressurizing mechanism 7, the input disk 1 and the output disk 2 and the power roller 3a, A pressing force is applied between 3b.

Then, the receiving portions 3e of the power rollers 3a, 3b and the trunnions 4a, 4b.
Thrust ball bearings 10a, 10b as rolling bearings are interposed on the surface facing to. These ball bearings 10a, 1
As shown in FIG. 2, 0b is a cage 11 in which a large number of through holes 11b are formed in a donut-shaped disc 11a, and a large number of balls 12 housed in the through holes 11b of the cage 11. It is composed of. Further, a recess is formed in the facing surface of the trunnions 4a, 4b facing the ball bearings 10a, 10b, and a steel seat 13 is fitted in the recess.

Next, the operation of the above embodiment will be described. Now, as shown in FIG. 1, it is assumed that the power rollers 3a and 3b are in the maximum deceleration position where they are in rolling contact with the minimum diameter portion of the input disk 1 and the maximum diameter portion of the output disk 2, respectively. In this state, when the input disk 1 is rotationally driven by a rotational drive source such as an engine, the rotational driving force of the input disk 1 causes the power rollers 3a and 3b to rotate.
Is transmitted to the output disc 2 via the input disc 1 and the output disc 2 and the power rollers 3a, 3b are pressed by the pressing mechanism 7 to rotate the output disc 2 slower than the input disc 1. Input disk 1 at speed
And rotate in the opposite direction.

From this state, the trunnions 4a and 4b are slightly moved in the axial direction by a pressing mechanism such as a hydraulic cylinder (not shown) to tilt the power rollers 3a and 3b toward the maximum diameter portion of the input disc 1. In response to this, the rotation speed of the output disk 2 rises, and the rotation speeds of the input disk 1 and the output disk 2 become equal at the position where the power rollers 3a, 3b are in the horizontal state, and from this, tilt toward the maximum diameter portion side. By doing so, the rotation speed of the output disk 2 becomes faster than that of the input disk 1, and the rotation speed of the output disk 2 becomes maximum when the power rollers 3a, 3b reach the maximum diameter portion of the input disk 1.

Thus, when power is transmitted between the input disc 1 and the output disc 2 via the power rollers 3a, 3b, the bowl-shaped portions 3c of the power rollers 3a, 3b rotate about the support shafts 5a, 5b. Therefore, when the torque fluctuation between the input disk 1 and the output disk 2 is small, the pressing force of the pressing mechanism 7 is applied to the power rollers 3a, 3b via the input disk 1.
Is transmitted to the bowl-shaped portions 3c of the power rollers 3a and 3b, and a predetermined pressing force is applied between the input disks 1 and the output disks 2 and the bowl-shaped portions 3c of the power rollers 3a and 3b to smoothly transmit power.

However, when a sudden torque fluctuation occurs between the input disk 1 and the output disk 2 such as when the vehicle starts, the pressing force of the pressing mechanism 7 causes the bowl shape of the power rollers 3a and 3b via the input disk 1. Due to the transmission to the portion 3c, an attempt is made to delay the transmission of the pressing force, but the rolling bearings 10a and 10b are interposed between the receiving portion 3e of the power rollers 3a and 3b and the receiving seat 13 of the trunnions 4a and 4b. Since it is inserted, the friction coefficient between the two is small and the frictional force of the power rollers 3a, 3b is reduced, so that a slight movement of the power rollers 3a, 3b to the output disk 2 side can be easily performed. As a result, a predetermined pressing force can be maintained between the output disk 2 and the power rollers 3a, 3b, and as a result, slip between them can be suppressed.

In addition, in the above embodiment, the case where the thrust ball bearing is applied as the rolling bearing has been described.
The present invention is not limited to this, and as shown in FIG.
A cage 20 having a large number of elongated holes 20a formed in parallel and the elongated holes 2
Thrust roller bearing consisting of roller 21 inserted in 0a
22 can also be applied.

[Effect of device]

As described above, according to the present invention, since the rolling bearing is inserted on the opposing surface of the power roller and the trunnion, the coefficient of friction between the power roller and the trunnion becomes small, and the power roller to the output disk side is reduced. Can be easily moved, and even if a sudden torque fluctuation occurs between the input disc and the output disc, the prescribed pressing force can be maintained between the power roller and the output disc, and the slip between the power roller and the output disc can be maintained. And the pressing force itself can be reduced to improve the power transmission efficiency.
The effect that it can withstand long-term use is obtained.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention, FIG. 2 is a plan view showing a thrust ball bearing, FIG. 3 is a plan view showing a thrust roller bearing, and FIG. 4 is a sectional view of a main part of a conventional example. Is. In the figure, 1 is an input disk, 2 is an output disk, 3a and 3b are power rollers, 4a and 4b are trunnions, 5a and 5b are support shafts, and 6
Is an input shaft, 7 is a pressure mechanism, 10a and 10b are thrust ball bearings, and 22 is a thrust roller bearing.

Claims (1)

[Scope of utility model registration request] 1. A toroidal continuously variable transmission in which a power roller eccentrically movably supported by a trunnion and rotatably supported and tiltable is disposed between an input disk and an output disk, wherein the power roller and the trunnion are provided. A toroidal type continuously variable transmission characterized in that a rolling bearing is inserted between the surfaces facing each other.