JPH0148425B2 - - Google Patents

Description

[Detailed description of the invention] [Technical field of invention] The present invention relates to a continuously variable transmission for a vehicle.

[Prior Art] Conventionally, continuously variable transmissions for vehicles have mainly combined a V-belt transmission with a torque converter or a centrifugal clutch to operate the vehicle from starting to stopping. In order to make the vehicle start smoothly, the clutch mechanism was equipped with a slip function. For this reason, none of them could be made smaller due to the problem of heat generation during slipping, and the torque loss due to slipping was large.

To solve this problem, friction-driven continuously variable transmissions have been proposed, as disclosed in Japanese Patent Publications No. 49-17166 and Japanese Patent Publication No. 49-48909, respectively. These are intended to provide smooth starting and stopping operations without using the aforementioned torque converter or centrifugal clutch. However, in this proposed invention, when the vehicle is stopped, the gear ratio is set to infinity and the rotation of the axle is brought to zero. The gear ratio of the transmission must be controlled to increase as the engine rotates. In particular, in order to respond to zero rotation of the axle without stopping the engine rotation even during sudden braking where the stopping time is extremely short, the driving force of the transmission control system must be extremely large, and the driving force of the transmission control system must be extremely large. This necessitated the installation of an actuator. Therefore, such conventional proposals were inevitably impractical. Furthermore, since the gear ratio is infinite when the axle is stopped and the rotation of the axle is zero, it is difficult to move the axle freely in this state. This was not suitable because it is essential that the device be able to be easily moved back and forth.

[Embodiments of the invention]

The present invention eliminates the above-mentioned conventional drawbacks, is suitable for two-wheeled vehicles, and also makes it easy for four-wheeled vehicles to be towed, for example, by other vehicles, and is practical, compact, and economical. Our objective is to provide a transmission.

[Embodiments of the invention]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The continuously variable transmission for a vehicle according to the present invention will be described in more detail below with reference to preferred embodiments shown in the accompanying drawings.

The figure is a basic configuration diagram of a continuously variable transmission for a vehicle showing an embodiment of the present invention. In the figure, 1 is the engine that is the power source of the vehicle, 2 is the throttle valve of the carburetor that controls the rotational force of the engine 1, 3 is the engine output shaft of the engine 1, and 4 is the sprocket 5 provided on the engine output shaft 3. A first transmission mechanism composed of a sprocket 6 and a chain 7, 8 is an input transmission plate 9, an output transmission plate 10, a conical rotor 11, a variable speed output shaft 12,
A friction-driven continuously variable transmission mechanism including a speed change ring 13, a speed change shaft 14, a pressure mechanism 15, and an auxiliary ring 16 of the rotor 11 is shown.
Note that a sprocket 6 is attached to the rotating shaft of the input transmission plate 9.
is provided.

Furthermore, 17 is a second transmission mechanism composed of a gear 18 provided on the speed change output shaft 12 and a gear 19 provided on the intermediate shaft 20;
2. An electromagnetic clutch mechanism for connecting and disconnecting 2, 23
30 is a wheel provided on the axle 22, and 30 is a transmission shaft 14.
32 is a throttle angle sensor that operates in response to an accelerator lever (not shown) that operates the throttle valve 2; 33 is a rotation of the wheel 23; 34 is a rotation sensor that detects the rotation speed of the engine 1; 35 is a clutch mechanism 21;
37 is a selection lever, 39, 40, 41 are the first transmission mechanism 4;
It protects the second transmission mechanism 17, the continuously variable transmission mechanism 8, etc., and each rotating shaft of the mechanism, that is, the shaft of the input transmission plate 9, the transmission shaft 14, and the transmission output shaft 1.
2 shows a case that holds bearings 24, 25, 26, and 27 that support the intermediate shaft 20 and the axle 22.

In such a configuration, the speed change function will be explained first. The transmission mechanism shown in the figure corresponds to the mechanism of the invention disclosed in Japanese Patent Publication No. 7-13221, and includes an input transmission plate 9 and a rotor 11.
The transmission mechanism formed by the combination of the transmission ring 13, the transmission ring 13, the rotor 11, and the output transmission plate 10 is similar to a so-called planetary gear transmission mechanism, and the transmission ratio of each transmission mechanism, that is, the former In this case, input transmission plate 9 and rotor 1
1. In the latter case, the output transmission plate 10 and rotor 11
Each speed ratio is determined by the position of the speed change ring 13. Therefore, ultimately the reduction ratio of the output transmission plate 10 to the input transmission plate 9 is also determined by the position of the transmission ring 13. Now, gear change ring 13
When the pressure contact point with respect to the rotor 11 moves to the L side position shown in the figure, the gear ratio increases and reaches a maximum value of infinity, that is, the rotation of the output transmission plate 10 becomes zero, and moves to the H side shown in the figure. As it moves, the ratio becomes smaller, and the minimum takes a predetermined value (generally about 1.5 to 2) determined by determining each dimension. That is, by selecting the position of the speed change ring 13, the speed ratio (reduction ratio) can be obtained steplessly from infinity to a predetermined value.

Note that the reason why there is a pressure contact force at the contact points where the input transmission plate 9, the output transmission plate 10, the rotor 11, and the speed change ring 13 come into contact with each other and no slippage occurs is due to the pressure generated by the pressure mechanism 15. That is,
The pressure mechanism 15 is a known pressure regulating mechanism, and the output transmission plate 1
A cam surface having an inclined surface is provided on each of the axially opposing surfaces of the transmission output shaft 12 and the transmission output shaft 12, and a spherical body is provided between the cam surfaces. A pressurizing force corresponding to the above-mentioned contact points is generated, and rotational force is transmitted at each contact point without slipping to apply the necessary pressure contact force to each of the above-mentioned contact points.

Next, the operation of each mechanism in each running state of the vehicle will be explained.

First, move the selection lever 37 in the direction of the arrow in the figure to bring the selection switch 36 to position D. In this state, when the clutch mechanism 21 is in the engaged state, and the vehicle is currently stopped and the engine 1 is rotating with the throttle 2 closed (this is called the idle state), the wheels 23 do not rotate. Therefore, not only the axle 22 but also the intermediate shaft 20 and the variable speed output shaft 12 connected to the intermediate shaft 20 by the second transmission mechanism 17 do not rotate, and furthermore, the output transmission via the pressure mechanism 15 does not rotate. Plate 10 is also not rotating.

On the other hand, the engine output shaft 3 is rotating in accordance with the angle of the throttle valve 2, and naturally the input transmission plate 9 via the first transmission mechanism 4 is rotating. However, the rotation speed depends on the gear ratio of the first transmission mechanism 4,
Generally, it takes a smaller value than the engine output shaft 3. Now, it is a well-known fact that the speed ratio must be infinite in order to satisfy the condition that the input transmission plate 9 rotates and the output transmission plate 10 stops rotating. Therefore, the speed change ring 13 must occupy the maximum position in the L direction shown in the figure. The predetermined position of the speed change ring 13 is the throttle opening sensor 32 and the vehicle speed sensor 33.
and the control device 3 in response to the output of the rotation sensor 34.
0 is a rotating electric machine 3 that drives a speed change shaft 14 in the left and right direction.
1 is activated. Therefore, the above-mentioned infinite speed ratio position is also determined by the throttle opening sensor 32 having a signal of zero opening.

Next, when attempting to start the vehicle, the throttle valve 2 is normally opened to increase the rotational speed of the engine 1 and also increase the driving torque of the engine 1. Therefore,
If the speed change ring 13 is gradually moved in the direction H shown in the figure from the infinite position in accordance with the amount determined by the throttle opening, the engine speed, and the vehicle speed, the output transmission plate 10 will start rotating accordingly. , the axle 22 also begins to rotate with a predetermined driving torque via the second transmission mechanism 17, intermediate shaft 20, and clutch mechanism 21, and the vehicle begins to move forward.

The forward speed of the vehicle is determined according to an increase in the rotation of the engine 1 according to the opening amount of the throttle valve 2 and a change in the gear ratio of the transmission mechanism 8 due to the movement of the transmission ring 13. Therefore, by using signals from the throttle angle sensor 32, vehicle speed sensor 33, and rotation sensor 34 that respond to the accelerator lever that determines the opening degree of the throttle valve 2, the driver's intention is reflected in the accelerator lever. It is thus possible to determine the forward speed of the vehicle. Further, the speed is controlled by the accelerator lever even when the vehicle is running after starting, but this time is also determined by changes in the angle of the throttle valve 2 and the gear ratio of the transmission mechanism 8, just as at the time of starting. However, during running, the rotation of the engine 1 and changes in driving force are mainly handled by operating the angle of the throttle valve 2, and the changes in the gear ratio of the transmission mechanism 8 are handled secondary.

Next, we will discuss stopping the vehicle.

There are two methods for stopping a running vehicle: one is to forcibly stop the vehicle using the brake, and the other is to close the throttle valve 2 and minimize the output of the engine 1, then stop the vehicle using a driving force greater than the driving resistance. There is a way.
Generally, these are combined to minimize the output of the engine 1, reduce the vehicle speed, and then use the brakes to stop the vehicle, but in any case, the engine 1 must continue to rotate even after the wheels 23 have stopped. . In other words,
It is necessary to maintain the idle state mentioned above.

Now, the time required for the wheels 23 to stop varies depending on the braking force, but in any case, it is extremely short, and it is significantly different from the moving speed of the speed change ring 13 of the speed change mechanism 8 under normal running of the vehicle. It is. Therefore, brake braking is applied and wheel 2
3, if the clutch control device 35 disconnects the clutch mechanism 21 when the vehicle speed falls below a predetermined value based on the output of the brake switch 38 that detects the braking and the output of the vehicle speed sensor 33, Even though the speed change ring 13 moves slowly and the wheels 23 are stopped, the rotation of the engine 1 does not stop even if the speed ratio of the speed change mechanism 8 does not take an infinite value.

Next, when the driver assumes that the vehicle is not running and selects the selection lever 37 to the P position of the selection switch 36 shown in the figure, the clutch control device 35 always disconnects the clutch mechanism 21, so that the axle The transmission of the rotational force of 22 to the engine 1 is also cut off.
Therefore, the driver can easily move the vehicle.

Here, the clutch mechanism 21 has a different function from the conventional clutch mechanism mentioned at the beginning. That is,
Conventionally, in order to make the vehicle start smoothly, the engine has a sliding function and starts coupling when the rotation of the engine 1 is considerably higher than the idle rotation. However, in the clutch mechanism of the continuously variable transmission for a vehicle of the present invention, since the starting operation is performed by the transmission 8, a slipping function is not necessary. Therefore, its shape can be made smaller than the conventional one, and the transmission efficiency is also improved.

〔Effect of the invention〕

As described above, the present invention uses a continuously variable transmission capable of continuously changing the gear ratio from infinity to a predetermined value as a transmission mechanism, and connects and disconnects the transmission system between the transmission mechanism and the axle. A clutch mechanism is inserted to cut off transmission between the transmission mechanism and the axle when the axle is not running and when the vehicle is stopped at a predetermined vehicle speed, so a large clutch mechanism that allows slipping is used. Without using the system, the vehicle can be started smoothly, and even if the vehicle stops in an extremely short period of time, the engine 1 can be prepared for the next start without stopping, and even when the vehicle is not running. In this case, it is possible to provide a continuously variable transmission device for a vehicle that is small in size, economical, and excellent in that it is possible to easily move the vehicle.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing the basic structure of a continuously variable transmission for a vehicle according to an embodiment of the present invention. 1... Engine, 2... Throttle valve, 3... Engine output shaft, 4... First transmission mechanism, 8... Speed change mechanism,
17...Second transmission mechanism, 20...Intermediate shaft, 21...
...Clutch mechanism, 22...Axle, 23...Wheel,
30...control device, 31...rotating electric machine, 32...
Throttle angle sensor, 33...Vehicle speed sensor, 3
4... Rotation sensor, 35... Clutch control device,
36...Selection switch, 38...Brake switch.

Claims (1)

[Claims] 1. A continuously variable transmission mechanism having an infinitely large speed ratio;
a first transmission means that engages an input shaft of the continuously variable transmission mechanism with an output shaft of the engine; a second transmission means that engages an output shaft of the continuously variable transmission mechanism with an axle of a vehicle; an intermittent means interposed between the transmission system and the transmission system of the axle for connecting and disconnecting the transmission system; a first control means for controlling the continuously variable transmission mechanism in response to at least an accelerator means for placing the engine in a prone position; a selection means capable of selecting running or non-running by a person; a braking detection means actuated in response to a braking means of the vehicle; a vehicle speed detection means responsive to the vehicle speed of the vehicle; the selection means, the braking detection means, and the vehicle speed. A second control means that operates the intermittent means by inputting a signal from the detection means, and the control means operates when the driver selects not to drive, or when the driver selects to drive and the vehicle speed is below a predetermined value while braking is being performed. and a second control means for cutting off the disconnection means when the disconnection occurs.