JPH0715308B2 - Continuously variable transmission - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a continuously variable transmission, and more specifically, a rotary member and a carrier are arranged on a coaxial core, and a taper cone is rotatably supported on the carrier. In addition, the present invention relates to a continuously variable transmission that is configured to form a transmission path between the taper cone and the rotary member and adjust the relative speed between the rotary member and the carrier by adjusting the position of the speed change member in contact with the taper cone. is there.

[Conventional technology]

Conventionally, as a continuously variable transmission configured as described above, there is one disclosed in JP-A-62-270858. In this reference, a taper cone rotates following an inner surface of a ring-shaped transmission member. By adjusting the position of the speed change member, the rotational power taken out from the rotating body can be adjusted steplessly including the rotation stop of the carrier.

[Problems to be Solved by the Invention]

However, in order to set the rotational power output from the device to the stop state as described above, it becomes necessary to accurately set and maintain the transmission member at a predetermined position of the taper cone.

That is, in the continuously variable transmission having the structure in which the carrier supports the taper cone in this manner, the setting position of the transmission member for stopping the output system exists as a “point” state,
It is difficult to set the speed change member to this “point” position. For example, when this device is provided in a traveling system such as a working vehicle, even if the vehicle body is stopped by operating the speed change member. , The car body may move at low speed.

An object of the present invention is to configure a continuously variable transmission that can reliably stop the rotation of the output system by operating the transmission member as easily as possible.

[Means for Solving the Problems]

A feature of the present invention is that a taper cone is rotatably supported on a carrier configured to be rotatable around an axis, and a rotating body that comes into contact with the taper cone from a side facing the carrier and a contact with the taper cone by moving along the axis. A speed change member for changing the position to set the speed change ratio between the carrier and the rotating body to an arbitrary value is provided, and the speed is increased by moving the speed change member to the carrier side, so that the speed change member moves to the rotating body side. In addition to constructing a continuously variable transmission system with the characteristic of decelerating by movement, an output stop mechanism that cuts off power by separating the taper cone from the rotating body by the pressing force of the transmission member when the transmission member is moved to the most decelerated position is provided. The present invention is provided, and its operation and effect are as follows.

[Action]

When the above characteristics are configured as shown in FIG. 1, for example, the speed change member (10) is operated to the deceleration side so that the speed change member (10) is located at a position (maximum speed reduction position) where the rotation of the output system almost stops. When it reaches, the rotating body (8) is pushed by the pressing force from the speed change member (10).
Is operated to move away from the taper cone (7), and the transmission from the taper cone (7) to the rotating body (8) is blocked.

In other words, with this configuration, the speed change member (10) can be accelerated and decelerated and stopped within the range of continuous operation of the speed change member (10), and the speed change member (10) that does not rotate contacts the rotating body (8). Therefore, the rotating body (8) reaches the braking state at the same time when the power is cut off.

In this configuration, the output stop mechanism (B) is the rotating body (8).
Structure that allows movement of the main shaft (3), and the rotating body (8)
It consists of a contact piece (8b) provided on the outer peripheral part of the.

〔The invention's effect〕

Therefore, the continuously variable transmission that can surely stop the rotation of the output system by operating the speed change member is configured relatively easily.

〔Example〕

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

As shown in FIG. 1, a case (1) is provided with a main shaft (3) whose both ends are supported via bearings (2) and (2), and an input gear is provided to the main shaft (3). A carrier (5) integrally formed with (4) is idle-supported, and its supporting shaft (6) is engaged with and supported by a holding portion (5a) formed on the carrier (5). Two taper cones (7) are provided, and the disk-shaped rotating body (8) is in contact with the large diameter side of these taper cones (7) and is slidable along the axis (P) of the main shaft (3), Further, each of the automatic pressure adjusting mechanisms (A) for adjusting the contact pressure between the rotating body (8) and the taper cone (7) is provided coaxially with the main shaft (3), and the shaft center (P) of the main shaft (3) is provided. ), The position of which is adjustable along the rod (9) parallel to the taper cone (7) ... A ring-shaped speed change member (10) and a taper cone (7) ... having a protruding edge (11a) in contact with an annular recess (7a) formed on the smaller diameter side of each, and free-rotating on the main shaft (3). A friction type continuously variable transmission is constructed by providing each supporting member (11) to be supported and further providing a sprocket (12) for taking out power from the main shaft (3).

Further, in this transmission, a needle bearing (13) is arranged between the carrier (5) where the input gear (4) is formed and the main shaft (3), and the spindle (6) and the taper cone (7). , A needle bearing (15) is disposed between the support member (11) and the main shaft (3) and the support member (11).
And needle carrier (1) between the carrier and carrier (5) respectively.
6) and thrust bearing (17) are arranged,
As shown in FIGS. 1 and 6, the automatic pressure adjusting mechanism (A) is slidable along the shaft core (P), and
A transmission member (18) externally fitted to the main shaft (3) so that torque can be transmitted, a plurality of cam surfaces (18a) formed on the transmission member (18), and a sleeve portion (8s) of the rotating body (8). ) And a plurality of cam surfaces (18a) formed on the ball (1
9) and a coil spring (20) for setting the initial pressure, and the automatic pressure adjusting mechanism (A) increases as the load increases.
As a result of the balls (19) ... riding on the cam surfaces (18a), (8a), the rotating body (8) is pressed against the tapered cone (7) more strongly.

In this way, the balls (19) are connected to the cam surfaces (8a), (18
The phenomenon of riding on a) is that the slide bearing (17) is provided between the carrier (5) and the support member (11) to close the thrust force from the automatic pressure adjusting mechanism (A). It can be said that it is caused by the reaction force from (5).

Further, the sleeve (8s) of the rotating body (8) has an operating shaft (2
The fork (22) connected to 1) is engaged, and even during transmission, pulling of the operating shaft (21) releases the contact between the rotating body (8) and the taper cone (7), and When the speed change member (10) is set to the maximum deceleration position on the outer peripheral portion of the rotating body (8), the speed change member (1
The contact piece (8b) on which the pressing force of (0) acts is provided, and when the speed change member (10) is operated in the deceleration direction and the output rotation from the device is almost stopped, the second As shown in the drawing, the taper cone (7) and the rotating body (8) are separated from each other by the pressing force acting on the contact piece (8b), so that the power to the rotating body (8) is cut off at the same time. Rotating body (8)
On the other hand, the rotation of the sprocket (12) is surely stopped by the braking force applied from the speed change member (10).

The contact piece (8b) and the structure that allows the rotating body (8) to slide relative to the main shaft (3) are collectively referred to as an output stop mechanism (B).

Further, flat surfaces (6a) ... Are formed at both ends of the support shaft (6), and are configured to come into contact with the holding portions (5a).

In this transmission, when the speed change member (10) is operated within the speed change operation range (S) while the power is transmitted to the input gear (4), the speed change member (10) is in a position where the speed change member (10) contacts. Since the radius of the taper cone (7) from the axis of rotation changes, that is, the circumferential length of the taper cone (7) changes at the position where the speed change member (10) comes into contact, the carrier (5) is set as a unit. When it is rotated by an amount, the amount of rotation of the taper cone (7) that rotates by following the inner surface of the speed change member (10) changes.
The rotation speed of the rotating body (8) to which power is transmitted from the taper cone (7) changes with respect to the rotation speed of the carrier (5), and as a result, there is no step from the sprocket (12) in parallel with the input gear (4). The power that has been shifted to is extracted.

Moreover, in this transmission, as shown in FIG. 2, the contact pressure of the rotating body (8) against the taper cone (7) is (F ₁ ),
When the contact pressure of the speed change member (10) with respect to the taper cone (7) is determined to be (F ₂ ), the contact position of the support member (11) with respect to the taper cone (7) is determined by the two contact pressures (F ₁ ) , (F ₂ ) and the moment acting on the taper cone (7) can be offset, so the contact pressure of the support member (11) to the taper cone (7) is determined as (F ₃ ). , If one of the holding portions (5a) is determined to be the center, then F ₁ × l ₁ + F ₃ × l ₃ −F ₂ × l ₂ = 0 holds and the balance of moments is maintained, and each of the vectors ( F ₁ ), (F ₂ ), and (F ₃ ) will be closed as shown in FIG.

Incidentally, in this transmission, the protruding edge (11
Since a) is fitted in the annular recess (7a) of the taper cone (7), when the position of the speed change member (10) is changed, the attitude of the taper cone (7) is slightly changed, and at the same time, the protruding edge is formed. The pressing direction of the (11a) against the annular recess (7a) changes to the direction of balance of moments to reach a stable state in an extremely short time, and as in the case where the load changes, the rotating body (8) Even when the contact pressure between the taper cone (7) and the taper cone (7) changes, a pressure proportional to this contact pressure acts on the taper cone (7) from the support member (11), so that the moment balance state is maintained.

[Another embodiment]

In addition to the above-described embodiment, the present invention can be variously implemented, for example, by supporting a support shaft of a taper cone so as to be swingable with respect to a carrier via a pin or the like, or by providing an automatic pressure adjusting mechanism on the power transmission side. Further, the continuously variable transmission can be used in various fields such as a machine tool in addition to being used in a self-propelled vehicle body such as being provided in a traveling transmission system of an agricultural work vehicle.

It should be noted that reference numerals are added to the claims for convenience of comparison with the drawings, but the present invention is not limited to the structures of the accompanying drawings by the entry.

[Brief description of drawings]

The drawings show an embodiment of a continuously variable transmission according to the present invention.
FIG. 4 is a cross-sectional view of the device, FIG. 2 is a cross-sectional view showing a contact state between a speed change member and a rotating member, FIG. 3 is a view showing a force acting on a taper cone, FIG. FIG. 6 is a view showing the holding portion, and FIG. 6 is a sectional view showing the structure of the automatic pressure adjusting mechanism. (5) …… Carrier, (7) …… Taper cone, (8)
...... Rotator, (10) ...... Transmission member, (B) …… Output stop mechanism, (P) …… Axis core.

Claims (1)

[Claims] 1. A taper cone (7) is rotatably supported on a carrier (5) rotatably around an axis (P), and the taper cone (7) is brought into contact with the carrier (5) from a side facing the carrier (5). The contact position with respect to the taper cone (7) is changed by moving the rotary body (8) along the axis (P) to set the gear ratio between the carrier (5) and the rotary body (8) to an arbitrary value. And a speed change member (10) are provided, and the speed is increased by moving the speed change member (10) to the carrier side.
Of the taper cone (7) and the rotor by the pressing force of the speed change member (10) when the speed change member (10) is moved to the maximum deceleration position. A continuously variable transmission including an output stop mechanism (B) for separating power from (8) to shut off power.