JP2001301682A - Steering damper system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the steering wheel operability when traveling at a low speed, to improve the controllability, and to restrict the excessive steering of a steering wheel in the condition that front wheels are floated when traveling at a high speed including the quick acceleration with the compact structure at a low cost by adjusting the damping force in response to the car speed. SOLUTION: This steering damper system has a cylinder 1 fitted to one of a steering wheel and a car body and a piston rod 3 fitted to the other of the cylinder 1 and the car body and for partitioning inside of the cylinder 1 into two oil chambers A and B. A flow capacity adjusting valve 7 for adjusting the flow capacity of the hydraulic fluid flowing in the bypass oil passage 6 in response to the operated variable of an accelerator 9 is provided on the way of the bypass oil passage 6 for connecting the two oil chambers A and B.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shock absorber used for a vehicle, for example, a steering damper system for stabilizing handling against a lateral force acting on a front fork of a motorcycle when a front wheel rises. .

[0002]

2. Description of the Related Art In recent years, large-sized (large-displacement) motorcycles have appeared, enabling high-speed running comparable to that of race cars. As a result, near the top of undulating roads and rough roads,
A situation has occurred in which the front wheels are likely to lift. In addition, a great feeling of acceleration can be obtained due to the great power, but on the other hand, the front wheel often floats during acceleration.

[0003] However, when the front wheels are lifted, if the vehicle receives a lateral force due to unevenness of the road surface, the steering wheel is swung because there is no resistance due to the grounding force, and the steering wheel deviates from a target course. At this time, if the driver tries to correct the course by handling, it is not possible to cope with a change in the lateral force, and when the lateral force is reduced, a transfer is generated in reverse, amplifying the swing, and consequently causing a fall.

[0004] On the other hand, in order to avoid the danger caused by such an unstable operation of the steering wheel, there has been an increasing demand for mounting a steering damper, including the conventional prevention of steering vibration. According to the steering damper, handling can be stabilized by resisting a lateral force acting on the front fork on the front wheel suspension side of the motorcycle.

[0005]

However, the provision of such a steering damper makes it possible to obtain a resistance corresponding to the lateral force on the steering wheel. When the damping force is increased, the resistance corresponding to the lateral force is reduced.On the other hand, when maneuvering at a large steering angle or driving at low speed, the steering becomes heavy, and the operability and maneuverability deteriorate. there were.

On the other hand, if the damping force of the steering damper is adjusted and the damping force is switched according to the vehicle speed,
It is thought that appropriate operation and steering will be possible, but if an electronic control method that is generally used is adopted for this purpose, the state grasp and control of dampers having switching functions, switching actuators, vehicle speed detectors and various devices Therefore, there is a problem that high cost and a large mounting space are required in addition to the installation of the related equipment, and it is difficult to realize economically and space.

The present invention has been made to solve the above-mentioned problems, and includes a method of adjusting a damping force according to a vehicle speed, including a deterioration in operability and handleability of a steering wheel at a low speed and a sudden acceleration. It is an object of the present invention to provide a steering damper system capable of reliably suppressing the steering wheel from being swung by a lateral force when the front wheels are lifted during high-speed running with a small and low-cost configuration.

[0008]

In order to achieve the above object,
A steering damper system according to the present invention includes a cylinder attached to one of a handle side and a vehicle body side,
A piston rod that is attached to the other of the handle side and the vehicle body side and has a piston that separates into the two oil chambers while sliding in the cylinder, and in the middle of a bypass oil passage that connects the two oil chambers. A flow control valve is provided for adjusting the flow rate of the hydraulic oil flowing through the bypass oil passage in accordance with the operation amount of the accelerator.

According to this aspect, in a high-speed region such as a motorcycle or the like at the time of rapid acceleration, the operation amount of the flow control valve can be made sufficiently large by rotating the accelerator largely by operating the steering wheel. The bypass oil passage that connects the two chambers in the cylinder is closed rapidly, increasing the damping force of the steering damper to prevent large swinging of the steering wheel and to resist the lateral force acting on the front fork. . On the other hand, in the low-speed range, the damping force of the steering damper is kept low to improve steering operability and maneuverability.

[0010] In the steering damper system according to the present invention, the bypass oil passage and the flow control valve are housed in the cylinder body. According to this aspect, the configuration of the steering damper body is reduced in size and size.

Further, in the steering damper system according to the present invention, the piston is provided with an orifice communicating with the two oil chambers. According to this aspect, even if the flow regulating valve is completely closed, the movement of the piston is prevented from being locked.

Further, the steering damper system according to the present invention is characterized in that a flow control valve is biased to one side by a spring and slides in the cylinder body against the spring in response to an accelerator operation. And an oil passage provided on the spool to adjust an opening amount with respect to the bypass oil passage.

According to this aspect, the flow regulating valve has a pressure equilibrium characteristic, and the control of the amount of high-pressure oil flowing through the bypass oil passage with a relatively small control input (flow control pulling force) can be realized with a small configuration. I have.

Further, in the steering damper system according to the present invention, the spool of the flow control valve is slidable in the cylinder body via a pull wire for transmitting an accelerator operation. According to this aspect, the operation of the steering wheel and the accelerator does not cause a large error or a delay with respect to a change in the vehicle speed.

Further, in the steering damper system according to the present invention, a return delay mechanism for delaying a return operation of the spool by a spring is disposed between the spool and the cylinder of the flow control valve. With this aspect,
When the accelerator is returned and decelerated or the accelerator is repeatedly operated, the damping force of the steering damper is prevented from suddenly changing, thereby preventing a sudden change in the steering holding force.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a conceptual diagram showing a configuration of a steering damper system of the present invention. In FIG. A block-shaped cylinder attached to either the handle side or the vehicle body side of the motorcycle, for example, the vehicle body side. A piston 2 that separates the two oil chambers A and B is slidably provided in the cylinder 1. ing.

The piston 2 has piston rods 3 at both ends, and these piston rods 3 are supported in a sealing manner 4 provided at both ends of the cylinder 1 in an oil-tight manner and freely in and out. One end of these piston rods 3 is attached to the handle. A seal ring 5 is mounted on the outer periphery of the piston 2 and operates between the two oil chambers A and B through a gap between the inner peripheral surface of the cylinder 1 and the outer peripheral surface of the piston 2 when the piston 2 slides. Prevents oil from leaking. Further, the piston 2 is provided with a small-diameter orifice 2a communicating with the two oil chambers A and B so that the movement of the piston 2 can be prevented from being completely locked.

A bypass oil passage 6 communicating with the two oil chambers A and B is provided within the thickness of the cylinder 1 main body, and a flow regulating valve 7 is provided in the middle of the bypass oil passage 6.
The flow control valve 7 functions to adjust the amount of hydraulic oil flowing between the two oil chambers A and B, and details will be described later.

On the other hand, a handlebar 8 of the motorcycle is provided with an accelerator rotator 9 as an accelerator so as to be rotatable. The accelerator rotator 9 operates the flow regulating valve 7 by the rotation thereof. One end of the pull wire 10 is fixed.

Therefore, when the pull wire 10 is pulled by the rotation operation of the accelerator rotor 9, the flow regulating valve 7 closes the bypass oil passage 6. Conversely, when the rotation of the accelerator rotor 9 is returned, the pull wire 10 is also pulled back, and the bypass oil passage 6 is opened. The accelerator rotor 9 is also fixed to one end of a pull wire 11 for opening and closing the throttle valve on the side of the intake system.

As shown in FIG. 2, the flow control valve 7 has a cylindrical storage hole 12 formed in a part of the cylinder 1 body, and is provided slidably in the storage hole 12 in the axial direction. And a cover member 14 for closing the opening of the storage hole 12 in which the spool 13 is stored. One end (lower end) of the storage hole 12 is pulled out of the cylinder 1 main body as shown in the figure, but the spool 13 is prevented from being pulled out by a stopper (not shown).

Further, a spring 17 for constantly urging the spool 13 downward is interposed between the spool 13 and the lid member 14 in the storage hole 12. Pull wire 10
Is slidably penetrated in the center hole 14a of the lid member 14 and also penetrates the center hole 13a of the spool 13.

A locking member 15 fixed to the other end of the pull wire 10 and having a diameter larger than the diameter of the pull wire is provided.
Locking recess 1 formed on the end face (lower end face) of spool 13
6. Accordingly, the pull wire 10 is prevented from coming off with respect to the spool 13 due to the force in the pulling direction of the pull wire 10.

On the outer periphery of the spool 13, a ring-shaped oil passage 18 for adjusting the opening amount to the bypass oil passage 6 is formed. Furthermore, the spool 1 is provided at two locations on the outer periphery of the spool 13 with the oil passage 18 interposed therebetween.
Seal rings 19 and 20 are provided to seal a gap between the outer peripheral surface of the storage hole 3 and the inner peripheral surface of the storage hole 12.

Reference numeral 21 denotes a mounting hole provided in a part of the cylinder 1 for mounting the cylinder 1 on the vehicle body side.
Is a mounting hole provided at the end of the piston rod 3 for mounting the same on the handle (steering) side.

Next, the operation will be described. First, when the accelerator rotor 9 of the steering wheel 8 is rotated, the pull valve 11 is pulled in, the throttle valve is opened, and the intake air amount and the fuel amount to the cylinder are reduced. The increase increases the rotational speed of the engine. At the same time, the other pull wire 10 is also pulled in, so that the spool 13 of the flow control valve 7 is drawn upward in the drawing.

When the amount of retraction is small or when there is no retraction, the oil passage 1
Reference numeral 8 denotes a state in which the bypass oil passage 6 is widely opened to allow the flow of the hydraulic oil between the oil chambers A and B to be free. Accordingly, the piston 2 can slide freely in the cylinder 1, the damping force of the steering damper is low, the steering wheel operation can be performed lightly on the vehicle body, and safe driving can be performed without impairing maneuverability.

On the other hand, when the motorcycle runs in an area at a low speed or higher, the accelerator rotor 9 is operated to rotate gradually larger, so that the pull-in amount of the pull wire 10 increases and the pull-in operation of the spool 13 also increases. Become. For this reason, the spool 13 moves upward in FIG.
Of the bypass oil passage 6 is reduced and finally closed.

For this reason, the flow rate of the working oil flowing through the bypass oil passage 6 is suppressed, and the movement of the piston 2 is suppressed, so that the damping force of the steering damper increases. That is, the damping force of the steering damper increases in proportion to the rotation amount (vehicle speed) of the accelerator rotor 9. As a result, especially when driving at high speeds including a sudden start, when the front wheels tend to lift up, or when the front wheels lift up, a fall accident due to the steering wheel being shaken by the lateral force caused by the unevenness of the road surface is anticipated. Can be avoided.

On the other hand, when the accelerator rotator 9 is returned, the pull wires 10, 11 are also pulled back in proportion to the operation amount. Since the slot valve is closed by pulling back the pull wire 11, the vehicle speed decreases,
On the other hand, when the pull wire 10 is pulled back by the spring 17, the spool 13 moves downward (down) in the storage hole 12, and the opening amount of the oil passage 18 of the spool 13 with respect to the bypass oil passage 6 increases. For this reason, the flow of the hydraulic oil flowing through the bypass oil passage 6 is smooth, and the movement of the piston 2 in the cylinder 1 is also free. Therefore, the steering wheel operation on the vehicle body at the time of low-speed running becomes light, and safe driving is realized. it can.

FIG. 3 shows another embodiment of the flow control valve 7 shown in FIG. 1, which comprises an air chamber 23 formed at a lower end of the spool 13 and a part of the cylinder 1, An orifice 24 is provided on the cylinder 1 main body side, is continuous with the air chamber 23, and has one end open to the outside air. In the air chamber 23, a spring 25 constituting the check valve A and a non-return valve 26 for opening and closing the other end (inner end) of the orifice 24 with a constant pressure by the spring 25 are provided. Have been. The check valve A and the orifice 24 constitute a return delay mechanism D of the spool 13.

In this flow control valve 7, when the accelerator rotor 9 is returned, the pull wire 10 immediately moves in the return direction, and receives the repulsive force of the spring 17 so that the spool 13 is also stored. The air in the air chamber 23, which is going to descend immediately in the hole 12, is gradually evacuated from the inner periphery of the non-return valve 26 to prevent the descending operation. Can be delayed.

In this way, the switching operation of the spool 13 when the accelerator rotator 9 is returned to decelerate or the accelerator rotator 9 is repeatedly operated can be delayed, whereby the steering can be performed. It is possible to prevent the damping force of the damper from suddenly changing.

The pull wire 10 used for adjusting the flow rate
Is used in motorcycle accelerators, speedometers, chokes, etc., has a proven track record in strength, quality, usage, and is economical. The pull wire 10 is provided independently of the pull wire 11 for the throttle valve as described above, and may be provided branched from the pull wire 11.

Further, since the flow regulating valve 7 has the pressure equilibrium characteristic, it does not receive the hydraulic pressure of the working oil flowing through the bypass oil passage 6, so that the operating force of the spool 13 can be reduced. Thus, even if the pull wire 10 is added, the operating force of the accelerator rotor 9 does not increase. Rather, a proper and appropriate operating force is obtained for the spool 13.

Further, since the switching of the damping force of the steering damper is performed in a low speed range or a middle speed range, the switching has already been completed at the time of rapid acceleration when the front wheels float.
The response during acceleration is already included.

[0037]

As described above, according to the present invention, the cylinder attached to one of the handle side and the vehicle body side,
A piston rod that is attached to the other of the handle side and the vehicle body side and has a piston that separates into the two oil chambers while sliding in the cylinder, and in the middle of a bypass oil passage that connects the two oil chambers. Since a flow rate adjusting valve for adjusting the flow rate of the hydraulic oil flowing through the bypass oil passage according to the operation amount of the accelerator is provided, the damping force can be adjusted according to the vehicle speed, and the operability of the steering at low speed traveling, It is possible to obtain an effect that deterioration of maneuverability and suppression of steering swing when the front wheels are lifted during high-speed running including rapid acceleration can be easily realized with a small and low-cost configuration.

Further, according to the present invention, since the bypass oil passage and the flow control valve are stored in the cylinder main body, it is possible to obtain an effect that the configuration of the steering damper main body can be reduced in size and size. Further, since the piston is provided with the orifice communicating with the two oil chambers, the movement of the piston can be prevented from being locked even when the flow control valve is completely closed.

According to the present invention, the flow control valve is biased to one side by a spring, and slides in the cylinder body against the spring in response to an accelerator operation, and is provided on the spool. And an oil passage for adjusting the opening amount with respect to the bypass oil passage.
Since the flow regulating valve has a pressure equilibrium state, there is obtained an effect that the control of the amount of high-pressure oil flowing through the bypass oil passage with a relatively small control input (flow control pulling force) can be realized with a small configuration.

Further, according to the present invention, the spool of the flow control valve can be slid into the cylinder body via the pull wire for transmitting the accelerator operation. It is possible to prevent large errors or delays.

Further, according to the present invention, since the return delay mechanism for delaying the return operation of the spool by the spring is disposed between the spool and the cylinder of the flow regulating valve, the accelerator is returned and deceleration is performed or the accelerator is repeated. When operated, the damping force of the steering damper can be prevented from suddenly changing, and the effect of achieving a stable steering operation can be obtained.

[Brief description of the drawings]

FIG. 1 is a configuration diagram conceptually showing a steering damper system according to an embodiment of the present invention.

FIG. 2 is an enlarged sectional view showing a flow control valve in FIG. 1;

FIG. 3 is an enlarged sectional view showing another embodiment of the flow regulating valve in FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cylinder 2 Piston 3 Piston rod 6 Bypass oil passage 7 Flow control valve 9 Accelerator (accelerator rotor) 10 Pull wire 13 Spool 17 Spring 18 Oil passage D Return delay mechanism A, B Oil chamber

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F16F 15/02 F16F 15/02 F

Claims (6)

[Claims] 1. A cylinder attached to one of a handle side and a vehicle body side, and a piston attached to the other of the handle side and the vehicle body side to separate the two oil chambers while sliding in the cylinder. And a flow regulating valve provided in the middle of a bypass oil passage connecting the two oil chambers, and adjusting a flow rate of hydraulic oil flowing through the bypass oil passage in accordance with an operation amount of an accelerator. A steering damper system characterized by the following. 2. The steering damper system according to claim 1, wherein the bypass oil passage and the flow control valve are housed in a cylinder body. 3. The steering damper system according to claim 1, wherein the piston is provided with an orifice communicating with the two oil chambers. 4. A spool which is biased to one side by a spring and slides in a cylinder body against the spring in response to an accelerator operation, and a bypass oil passage provided in the spool. The steering damper system according to claim 1, further comprising: an oil passage for adjusting an opening amount of the steering damper. 5. The steering damper system according to claim 4, wherein a spool of the flow control valve is connected to an end of a pull wire for transmitting an accelerator operation and slides in the cylinder body. 6. The steering damper system according to claim 4, wherein a return delay mechanism for delaying the return operation of the spool by the spring is disposed between the spool and the cylinder of the flow rate control valve.