JP2003072663A - Body attitude adjusting device for two-wheeled vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent abnormal sinking in one or both of a front wheel side and a rear wheel side of a two-wheeled vehicle during traveling on a sloping road with two people riding or loaded with baggage. SOLUTION: In the body attitude adjusting device, a preload of a suspension spring 10 in a suspension 1 is adjusted by a hydraulic screw pump 13 driven by a driving means B. It is provided with pressure sensors 25 and 26 detecting a pressure of each oil chamber partitioned by a free piston 16 in the hydraulic screw pump 13 and a vertical acceleration sensor 28 detecting vertical acceleration of a sprung section of the two-wheeled vehicle. The suspension spring preload of the suspension 1 is adjusted by the hydraulic screw pump driven by the driving means in response to preload adjusting data calculated by a controller 27 on the basis of outputs of the sensors 25, 26 and 28.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle body posture adjusting device for a two-wheeled vehicle for suppressing changes in the vehicle body posture when the two-wheeled vehicle runs on a slope.

[0002]

2. Description of the Related Art Unlike a four-wheeled vehicle, a two-wheeled vehicle is a vehicle that is very useful and easy to use for traveling or parking on a narrow road or a parking lot because of its small width. On the other hand, the weight ratio of the occupant and the freight to the vehicle body weight is much higher than that of the four-wheeled vehicle, and the occupant supports the body on the two-wheeled vehicle by the steering wheel, the seat and the steps.

[0003]

However, due to the weight ratio of the occupant to the vehicle body weight and the occupant's support form in a two-wheeled vehicle as described above, when the vehicle travels on a slope, the occupant's posture changes and the short wheel length is shortened. The center of gravity on the spring including the body weight may move between the bases, and the leaning of the vehicle body may become larger than the leaning of the slope.

Further, in the case of two passengers or luggage loading, the inclination of the vehicle body is inevitably large, the posture of the vehicle body becomes unbalanced, and running stability deteriorates.

Further, due to the movement of the center of gravity as described above, the front wheel side in the downward traveling on the slope and the rear wheel side in the upward traveling abnormally largely sink, impairing the running stability and the riding comfort. There was a problem of doing.

[0006] In addition, if the vehicle body is pitched by a braking operation or an accelerating operation, the rider is required to have an unreasonable posture. There was a problem that people became very tired.

The present invention solves the above-mentioned conventional problems, and one or both of the front wheel side and the rear wheel side of a two-wheeled vehicle is abnormally sunk when a two-person vehicle or luggage is loaded, or when traveling on a slope. An object of the present invention is to provide a vehicle body posture adjusting device for a two-wheeled vehicle, which can prevent the vehicle from slipping in and can prevent running stability and riding comfort from being deteriorated due to pitching, and can also avoid significant fatigue due to driving operation.

[0008]

[Means for Solving the Problems] To achieve the above object,
A vehicle body posture adjusting device for a two-wheeled vehicle according to a first aspect of the present invention is provided in a vertical acceleration sensor for detecting a vertical acceleration on a spring of the two-wheeled vehicle, and on one or both of front and rear wheel suspensions of the two-wheeled vehicle. A suspension spring preload adjusting mechanism for adjusting the preload of the suspension spring, a hydraulic screw pump having a free piston for partitioning the cylinder into a first oil chamber and a second oil chamber, and the second
A spring for urging the free piston toward the first oil chamber, and an oil passage connecting the second oil chamber with the oil chamber of the suspension spring preload adjusting mechanism.
It is provided slidably in the axial direction in the cylinder,
A piston of the hydraulic screw pump that divides the first oil chamber between the free piston and a drive means having an output shaft screwed to a rod integrated with the piston;
First pressure sensor and second pressure sensor for detecting respective pressures in the oil chamber and the second oil chamber, outputs of the first pressure sensor and second pressure sensor, and acceleration of the vertical acceleration sensor. Based on the data output, the controller calculates the preload adjustment data and controls the suspension spring preload adjustment mechanism by the drive means via the hydraulic screw pump by an adjustment amount corresponding to the preload adjustment data. It is the one.

With this, it is possible to prevent the vehicle body from tilting when two passengers are loaded or luggage is loaded, and to suppress the abnormal vehicle body inclination and excessive pitching when traveling on a slope, and to stabilize the vehicle body posture and running stability. A comfortable ride can be realized.

Further, in the vehicle body attitude adjusting device for a two-wheeled vehicle according to a second aspect of the present invention, the vertical velocity averagely calculated by the controller by the vertical acceleration sensor installed near the middle of the pitching behavior of the vehicle body is averaged. The suspension spring preload adjusting mechanism by the drive means so as to decrease the preload of the suspension spring in the suspension when the acceleration is applied, and to increase the preload when the vertical speed is an average deceleration. Is to control the operation of each.

As a result, the preload adjustment amount can be set in accordance with the size of the vertical speed to be increased or decreased to make the vehicle body substantially horizontal.

Further, in the vehicle body attitude adjusting device for a two-wheeled vehicle according to a third aspect of the present invention, the controller is configured so that the controller sets the preload adjustment amount of the suspension spring to be large in proportion to the absolute value of the vertical speed. It is intended to control the means.

Thus, the state where the stability of the vehicle body is lowered can be quickly returned to the stable state of the vehicle body.

According to a fourth aspect of the present invention, there is provided a vehicle body posture adjusting device for a two-wheeled vehicle, wherein the hydraulic screw pump has a cylinder having a piston that is axially slidably driven by a driving means, and the piston is used for the hydraulic screw pump. Separately into a metering cylinder having a first oil chamber that communicates with an oil chamber that is partitioned within the cylinder and that is partitioned by a free piston, and a second oil chamber that communicates with the oil chamber of the suspension spring preload adjusting mechanism. It was installed.

Thus, the alarm cylinder or the metering cylinder can be freely installed at any position on the vehicle body apart from the suspension, and the installation of the drive means can be easily selected and secured.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram conceptually showing a body attitude adjusting device for a two-wheeled vehicle.
Reference numeral 1 denotes a suspension installed on one or both of the front wheel side and the rear wheel side, here, a front fork which is a front wheel side suspension.

The front fork 1 has a suspension spring preload adjusting mechanism A for adjusting the preload of the suspension spring.

The front fork has a bottomed cylindrical upper lid 4 screwed onto the inner circumference of the upper end of the inner tube 2 via a seal ring 3, and an oil chamber 5 in the bottomed cylindrical portion of the top lid 4. The oil chamber 5 is provided between the oil chamber partition plate 6 and the oil chamber partition plate 6 slidably provided in the bottomed cylindrical portion.
And a rod 8 that is integral with the piston 8 and a pressing member 11 of a suspension spring 10 that is connected to the end of the rod 9.

The rod 9 penetrates through the center of the bottom of the upper lid 4 and projects toward the suspension spring 10.

Reference numeral 12 is a ring fitted to the inner circumference of the bottomed cylindrical portion to prevent the oil chamber partition plate 6 from coming off.

Further, 13 is a hydraulic screw pump, which comprises a cylinder 14 in which a piston 15 and a free piston 16 define a first oil chamber 17 and a second oil chamber 18.

Piston 15 and free piston 16
Is provided in the cylinder 4 so as to be slidable in the axial direction, and the free piston 16 is constantly provided in the second oil chamber 18.
A spring 19 that biases the side is interposed.

The second oil chamber 18 has an oil passage (pipe) 2
It communicates with the oil chamber 5 via 0. Further, here, the inner tube 2, the oil chamber 5, the piston 8, the rod 9 and the pressing member 11 constitute the suspension spring preload adjusting mechanism A as a hydraulic jack.

One end of a rod 21 that goes in and out of the cylinder 14 is attached to the piston 15, and the output shaft of a speed reducer 23 that is interlocked with an electric motor 22 that can be driven in forward and reverse directions is attached to the outer periphery of the rod 21. 24 are screwed together, and the electric motor 22 and the speed reducer 23 are connected to the drive means B.
Are configured.

The first oil chamber 13 and the second oil chamber 14 described above.
A first pressure sensor 25 and a second pressure sensor 26 for detecting pressure (hydraulic pressure) are provided in the.

A controller 27 receives the pressure signals Pa and Pb output from the first pressure sensor 25 and the second pressure sensor 26, and the controller 27 receives the pressure signals Pa and Pb, for example, the current vehicle state. Calculate the high signal.

Further, 28 is a vertical acceleration sensor for detecting vertical acceleration on the spring of the two-wheeled vehicle, and is arranged so as to face the vicinity of the pitching center of the vehicle body, that is, an intermediate position between the maximum level and the minimum level of the pitching behavior. It is set up.

The vertical acceleration sensor 28 detects the vertical acceleration signal of the vehicle body, and the control 27 integrates and calculates the vertical velocity of the vehicle body based on the vertical acceleration signal to obtain an appropriate vehicle height according to the control map shown in FIG. According to the height difference (error) from the vehicle height signal obtained from the outputs of the pressure sensors 25 and 26, the electric motor 22 is rotated forward by a predetermined rotation speed or a predetermined time so as to further correct the height difference. Reverse control.

Therefore, the hydraulic screw pump 13 operates,
The hydraulic oil is supplied and discharged between the second oil chamber 18 and the oil chamber 5,
The suspension spring preload adjusting mechanism A is driven.

As a result, the suspension spring 10 can be compressed by the downward movement of the pressing member 11 when the electric motor 22 rotates in the normal direction, while the suspension spring 10 can be expanded when rotating in the reverse direction.

The controller 27 constantly monitors the acceleration data output by the vertical acceleration sensor 28, and the magnitude of the vertical velocity integrated and calculated is + (plus) on average,
That is, when it is determined that the speed is the acceleration speed, the preload adjustment data for reducing the suspension preload is calculated accordingly.

On the other hand, when the controller 27 determines that the magnitude of the vertical velocity calculated by integration is on average − (minus), that is, the deceleration, the preload adjustment data for increasing the suspension spring preload is correspondingly provided. Calculate

When obtaining the calculation result, the electric motor 22 is driven so as to correct the vehicle height at that time to an appropriate vehicle height by using the control map.

Therefore, the rod 21 moves in the axial direction,
The piston 15 and the free piston 16 are moved to supply and discharge the working oil between the second oil chamber 18 and the oil chamber 5.

As a result, the piston 8 moves and adjusts the preload on the suspension spring 10. In this way, by increasing or decreasing the adjustment amount of the preload according to the magnitude of acceleration and deceleration, it is possible to bring the vehicle body posture to a substantially horizontal state in spite of the movement of the center of gravity position of the vehicle body while traveling on a slope or the like. It will be possible.

The acceleration signal, which is the basic signal in the present invention, is the product of the road (slope) gradient and the change in vehicle speed. If the absolute value of the product is high on both the acceleration side and the deceleration side, Since the running stability is reduced, the amount of posture correction of the vehicle body is increased by adjusting the preload in consideration of safety. The adjustment amount of the preload is set by the rotation amount of the electric motor 22.

Further, in this embodiment, since the length and arrangement of the conduit 20 can be freely set, the screw pump 13 can be mounted at any place where the operation of the front fork 1 and the external appearance are not hindered. That is, it is possible to easily secure the installation space for the drive unit B including the screw pump 13.

In each of the above embodiments, the operation of the front fork which is the front wheel side suspension has been mainly described, but the same preload adjusting function is also applied to the rear wheel side suspension as a rear cushion unit in order to suppress pitching. It goes without saying that you can have it.

On the other hand, there is a case where a load such that the front portion of the vehicle body sinks due to a brake operation during traveling on a slope. In this case, the inner tube 2 sinks into the outer tube (not shown) and the suspension spring 10 is used. And the piston 8 moves upward relative to the inner tube 2.

Therefore, the oil pressure in the oil chamber 5 rises, the oil pressure in the second oil chamber 18 of the hydraulic screw pump 13 also rises via the oil passage 20, and the oil pressure difference from the first oil chamber 17 is increased. And the equivalent pressure of the spring reaction force of the spring 19 moves the free piston 16 by a predetermined amount.

On the other hand, the first oil chamber 17 and the second oil chamber 1
The pressure at 8 is detected by the pressure sensors 24 and 25, and the controller 27 detects these pressure signals and the oil chamber 1 described above.
The vehicle height state is calculated with reference to the cross-sectional areas of 7, 18, and 5 and the oil amount data, and the difference from the appropriate vehicle height obtained from the control map is obtained, and the required amount of hydraulic oil corresponding to this difference is calculated. Calculate and set the adjustment value of Pa-Pb.

For this reason, the electric motor 22 operates in the Pa-P
For example, normal rotation driving is performed by the number of rotations (or driving time) corresponding to the control amount according to the adjustment value of b, and the piston 15 is moved rightward into the cylinder 14 via the reduction gear 23.

The rightward movement of the piston 15 increases the pressure in the first oil chamber 17 and causes the free piston 16 to move rightward in accordance with the pressure difference between the first oil chamber 17 and the second oil chamber 18.

Therefore, the hydraulic oil in the second oil chamber 18 is
The oil is supplied to the oil chamber 5 in the inner tube 2 which constitutes the suspension spring preload adjusting mechanism A through the oil passage 20, and the oil pressure in the oil chamber 5 is increased. This hydraulic pressure functions to raise the inner tube 2 with respect to the outer tube via the suspension spring 10.

That is, it is possible to automatically suppress the front wheel side suspension from sinking when traveling on a slope and raise the vehicle body on the front wheel side to maintain the vehicle body posture in an appropriate posture.

The hydraulic screw pump 13 is driven by a driving means B so that the piston 15 is slidable in the axial direction.
And a second oil communicating with an oil chamber defined in the cylinder by the piston 15 and a first oil chamber defined by the free piston and the oil chamber of the suspension spring preload adjusting mechanism. It may be installed separately from a metering cylinder having a chamber.

In this case, the installation position of the drive means B on the vehicle body can be easily selected together with the cylinder and the metering cylinder.

As described above, according to each of the embodiments, even when the vehicle body posture greatly changes due to two-seater, cargo loading, or traveling on a slope, the vehicle body posture can be automatically adjusted to an appropriate posture. Therefore, for example, it is possible to prevent the headlight from pointing vertically at an abnormal angle and directly hit the driver of the oncoming vehicle, and thus to prevent an accident of the oncoming vehicle.

Further, since the variation of the body posture is suppressed,
The damping force of the front wheel side suspension and the spring constant of the suspension spring 10, and the steady damping force of the rear wheel side suspension and the spring constant of the suspension spring can be reduced. The actuation amount can be set to a large value and the riding comfort can be improved.

Further, the front fork 1 serving as the front wheel side suspension and the hydraulic screw pump 13 and the metering cylinder and the cylinder or front fork are connected by an oil passage as a conduit. By doing so, it becomes easy to set the equipment space in these vehicle bodies. Further, the pressure sensors 25 and 26 are small and lightweight, and can be easily mounted on the hydraulic screw pump 13 and the metering, and can be installed without deteriorating the appearance.

[0051]

As described above, according to the present invention, in the hydraulic screw pump driven by the drive means for adjusting the preload of the suspension spring in the suspension, the oil divided by the free piston is provided in the hydraulic screw pump. A pressure sensor that detects the pressure in the chamber and a vertical acceleration sensor that detects the vertical acceleration on the spring of the two-wheeled vehicle are provided, and the preload adjustment data calculated by the controller using the control map based on the output of each of these sensors is used. Accordingly, the suspension spring preload adjustment of the suspension is carried out by the hydraulic screw pump driven by the above-mentioned driving means, so that the vehicle body can be prevented from tilting when two passengers or luggage is loaded, and traveling on slopes, etc. Suppresses abnormal leaning and excessive pitching of the vehicle body while stabilizing the body posture and running It is possible to realize the stability, as well as a comfortable ride.

Further, when the vertical speed integrated and calculated by the vertical acceleration sensor installed near the middle of the pitching behavior of the vehicle body in the controller is an average speed increase, the preload of the suspension spring in the suspension is reduced. On the other hand, when the vertical speed is an average deceleration, the suspension spring preload adjusting mechanism is controlled by the driving means so as to increase the preload. The preload adjustment amount can be set according to the size of the vehicle side or the deceleration side to bring the vehicle body substantially horizontal.

Further, since the controller controls the driving means so as to set the preload adjustment amount of the suspension spring to be large in proportion to the absolute value of the vertical speed, the stability of the vehicle body is deteriorated. The state in which the vehicle is in a stable state can be quickly returned to the stable state of the vehicle body.

Further, the hydraulic screw pump is connected to a cylinder having a piston which is slidably driven in the axial direction by a driving means, and an oil chamber defined in the cylinder by the piston, and is connected by a free piston. Since the divided first oil chamber and the metering cylinder having the second oil chamber communicating with the oil chamber of the suspension spring preload adjusting mechanism are separately installed, the cylinder, the metering cylinder, and the driving means are installed. The effect that it can be freely installed at any position on the vehicle body apart from the suspension is obtained.

[Brief description of drawings]

FIG. 1 is a configuration diagram conceptually showing a vehicle body attitude adjusting device for a two-wheeled vehicle according to an embodiment of the present invention.

FIG. 2 is a control map used by the controller of the present invention for adjusting the preload of a suspension spring.

[Explanation of symbols]

A Suspension spring preload adjustment mechanism B drive means 1 front fork (suspension) 5 oil chamber 10 Suspension spring 13 Hydraulic screw pump 14 cylinders 15 pistons 16 Free piston 17 First oil chamber 18 Second oil chamber 19 spring 20 oil passage (pipe) 24 Output shaft 25 First pressure sensor 26 Second pressure sensor 27 Controller 28 Vertical acceleration sensor

Claims (4)

[Claims] 1. A vertical acceleration sensor for detecting vertical acceleration on a spring of a two-wheeled vehicle, and a suspension spring provided on one or both of the front wheel side and the rear wheel side of the two-wheeled vehicle to adjust the preload of the suspension spring. A preload adjusting mechanism, a hydraulic screw pump having a free piston that divides the interior of the cylinder into a first oil chamber and a second oil chamber, and the second oil chamber, the free piston being provided in the first oil chamber. A spring biasing the oil chamber, an oil passage connecting the second oil chamber to the oil chamber of the suspension spring preload adjusting mechanism, and an oil passage axially slidable in the cylinder are provided. A piston of the hydraulic screw pump that defines the first oil chamber between the piston and the piston, drive means having an output shaft screwed to a rod integral with the piston, the first oil chamber, and A first pressure sensor and a second pressure sensor for detecting the respective pressures of the first and second oil chambers, and the first pressure sensor and the second pressure sensor.
On the basis of the outputs of the pressure sensor and the second pressure sensor and the acceleration data output of the vertical acceleration sensor, and calculates the preload adjustment data according to the preload adjustment data by the drive means. A vehicle body posture adjusting device for a two-wheeled vehicle, comprising: a controller that controls the operation of the suspension spring preload adjusting mechanism via a screw pump. 2. The controller, when the vertical velocity integrated by the vertical acceleration sensor installed near the middle of the pitching behavior of the vehicle body is an average acceleration,
The suspension spring preload adjusting mechanism is operated and controlled by the driving means so as to reduce the preload of the suspension spring in the suspension, while increasing the preload when the vertical speed is an average deceleration. The vehicle body posture adjusting device for a two-wheeled vehicle according to claim 1, wherein 3. The two-wheeled vehicle according to claim 1, wherein the controller controls the drive means so as to set the preload adjustment amount of the suspension spring to be large in proportion to the absolute value of the vertical speed. Body attitude adjustment device. 4. The hydraulic screw pump communicates with a cylinder having a piston that is axially slidably driven by a driving means, and an oil chamber defined by the piston in the cylinder, and defined by a free piston. The two-wheel vehicle according to claim 1, wherein the two-wheel vehicle is installed separately from a first oil chamber and a metering cylinder having a second oil chamber communicating with the oil chamber of the suspension spring preload adjusting mechanism. Body attitude adjustment device.