JPS61249889A - Variable suspension system for motorcycle - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a variable suspension device for a motorcycle that effectively prevents the body of the motorcycle from sinking in the initial stage during braking.

(Prior Art) In motorcycles, the vehicle body sinks (hereinafter referred to as nose dive) during braking, which adversely affects ride comfort control and posture control of the motorcycle.

Conventionally, various suspension devices for preventing this nose dive have been proposed.

JP-A-58-112818 [Shock absorber control device] calculates vehicle deceleration from a signal detected by a vehicle speed sensor, and when this vehicle deceleration exceeds a predetermined reference speed, or a stop switch is activated. A configuration is disclosed that increases the damping force of the shock absorber when the shock absorber is closed.

(Problems to be Solved by the Invention) In the above device, a low-accuracy speed switch type sensor is used as a vehicle speed sensor. In the case of this vehicle speed sensor, it takes more than 100 m5 to detect and calculate the vehicle speed, so it takes time and effort to detect or calculate deceleration.
It was not possible to effectively prevent the initial subsidence.

In other words, since the deceleration detected by the vehicle speed sensor is rough, if the brakes are applied while the vehicle is running at high speed, there is a high possibility that the shock absorber will sink while the deceleration is being calculated.

In addition, the damping force of the shock absorber can only be controlled in two stages, hard and soft, and the damping force at low speeds in particular is not controlled, and sufficient ride comfort and posture control cannot be achieved. There wasn't.

The purpose of the present invention is to maintain the damping force of the damper at a high level immediately during the initial stage of braking, and to variably control the damping force of the damper during the middle stage of braking in multiple stages to achieve necessary and sufficient ride comfort control.
An object of the present invention is to provide a variable suspension device for a motorcycle that can realize attitude control.

(Means for Solving the Problems) In order to achieve the above object, a variable suspension device for a motorcycle according to the present invention is provided with a variable suspension device for a motorcycle provided with a damper having a variable damping force mechanism. a vehicle speed sensor that detects the traveling speed of the vehicle and outputs a vehicle speed signal; a brake switch that outputs a brake signal when the brake is applied; and a brake switch that increases the damper for a certain period of time immediately when the brake signal is received. A variable damping force that maintains the damping force at the same level, then controls the damping force in multiple stages according to the deceleration calculated from the vehicle speed signal, and maintains the previous damping force for a certain period of time when the brake signal disappears. It is comprised of a damping force control circuit that generates and outputs a signal, and a drive section that drives the damping force variable mechanism according to the damping force variable signal.

(Example) Hereinafter, the present invention will be described in detail with reference to the drawings and the like.

FIG. 1 is a block diagram showing an embodiment of a variable suspension device for a motorcycle according to the present invention, FIG. 2 is a flowchart for explaining the operation of a control circuit used in the device of the embodiment, and FIG. 4 is a schematic diagram showing an embodiment of a damper with a variable damping force mechanism used in the same embodiment device, and FIG. 4 is a waveform diagram for explaining the operation of the variable suspension device for a motorcycle according to the present invention. .

In FIG. 1, 1 is a vehicle speed sensor, 2 is a buffer, 3 is a brake switch, 4 is a buffer, 5 is a control circuit, 6 is a drive circuit, and 7 is a drive section.

The vehicle speed sensor 1 is a sensor for detecting the traveling speed of a motorcycle, and in this embodiment, a reed switch type sensor is used. The output of the vehicle speed sensor 1 is connected to a control circuit 5 via a buffer 2.

The brake switch 3 is a switch that is turned on and off in conjunction with the operation of the brake. The output of the brake switch 3 is connected to a control circuit 5 via a buffer 4.

The control circuit 5 includes a vehicle speed sensor 1. This circuit generates and outputs a variable damping force signal based on the signal from the brake switch 3 according to the flowchart shown in FIG.

As shown in FIG. 2, during normal driving, the control circuit 5 calculates the vehicle speed from the vehicle speed signal detected by the vehicle speed sensor 1 (101), and sets the optimal damping force stage number k for the vehicle speed (101). 102), the control circuit 5 outputs a damping force variable signal corresponding to the number k of damping force stages (103).

Next, it is determined whether or not the brake switch 3 is turned on (104). If it is turned on, the process proceeds to step 105; if it is off, the process proceeds to step 111.

When it is determined that the brake switch 3 is on, the number k of damping force stages is set according to the vehicle speed calculated in step 101 (105). The number of damping force stages during braking is as follows:
For example, in the case of a four-stage variable damper, a relatively high number of stages, such as k-3 or 4, is chosen. In the case of a three-stage variable damper, it may be set to -3.

The control circuit 5 outputs a damping force variable signal corresponding to the number k of damping force stages (106).

Next, deceleration is calculated based on the vehicle speed signal from the vehicle speed sensor 1 (107). Set the optimal number of damping force stages k based on the deceleration calculated in step 107 (108)
. The control circuit 5 outputs a damping force variable signal corresponding to the number k of damping force stages (106). Further, a damping force holding time T corresponding to the deceleration is set and held in the damping force variable signal (110).

Returning to step 104, it is determined whether or not the brake switch 3 is on, and if it is on, the step 105 to
Repeat 110. When the brake switch 3 is turned off, the damping force variable signal is held until the holding time set in step 110 has elapsed, and after the holding time has elapsed, the control returns to normal driving (10
1-103).

An output of the control circuit 5 is connected to a drive circuit 6. The drive circuit 6 is a circuit that drives the drive unit 7 based on the variable damping force signal generated by the control circuit 5. The drive unit 7 is for driving the damping force variable mechanism 20 provided in the damper 10 in stages, and uses, for example, a linear solenoid. Here, 71 is a front extension side drive section.

72 is the front overwhelming drive part, 73 is the rear expansion side drive part, 7
4 is a rear overwhelming drive section.

As shown in FIG. 3, the damper 10 is provided with a damping force variable mechanism 20, and this damping force variable mechanism 20 is controlled by a damping force stage number signal generated by a microcomputer 7 via an actuator 9. The damping force of the damper 10 is varied in stages.

The cylinder 11 of the damper 10 is a double cylindrical cylinder, and has an outer hydraulic chamber 12 and an inner hydraulic chamber 13 formed therein. An annular piston 15 is inserted into the outer hydraulic chamber 12, and a cylindrical piston rod 16 is connected to the piston 15. A coil spring 17 is provided between the piston rod 16 and the inner tube 14 of the cylinder 11.

A variable damping force mechanism 20 is provided on the side wall of the cylinder 11. The outer hydraulic chamber 12 and the inner hydraulic chamber 13 of the cylinder 11 are connected by a hydraulic passage 21 . A plunger 22 is movably provided in the hydraulic passage 21, and the opening degree of the orifice 23 can be varied in multiple stages according to its stroke. The stroke of this plunge +22 is driven by the aforementioned drive section 7.

Next, the operation of the variable suspension device for a motorcycle according to the present invention will be explained with reference to FIG. Generally, the number of damping force stages can be said to be varied in m stages, but here, for the sake of simplicity, an example will be described in which it is varied in three stages (m=3).

Assume that the brake is applied and the brake switch 3 is closed at the time of TI. At the same time as the brake switch 3 closes, the damping force stage number k is temporarily set to the highest stage m (m=3
), and the damping force of the damper 10 is maintained with this number of stages of damping force variable signals.

This allows the time required to detect and calculate deceleration to
Prevent the vehicle body from sinking.

From this point on, the damper is operated with the damping force variable signal of the optimum damping force stage number k (Fig. 4 (b)) according to the deceleration (Fig. 4 (a)) calculated from the vehicle speed signal detected by the vehicle speed sensor 1. 10
control the damping force of

Assuming that the brake switch 3 is opened at time T2, the damping force stage number (m-1) is held for the holding time T set at step 110 in FIG. 2.

This makes it possible to prevent pitching that suddenly occurs when the damping force changes from high damping force to low damping force. After this holding time T has elapsed, normal damping force control is performed.

Assuming that the brake switch 3 is turned on at time T3, similarly, the damping force stage number k is temporarily set to the highest stage m (here, m-3), and the damper 10 is activated by the damping force variable signal of this stage number. drive At this time, since the deceleration is small, the number of damping force stages thereafter is controlled by (m-1).

Next, assume that the brake switch 3 is turned on again at time T5, and that the brake is once turned off and then applied again.

Since the period from time T6 to time TI is shorter than one hour, the damping force remains at -(m-1). Other operations are the same as described above.

(Effects of the Invention) As described in detail above, according to the present invention, the damping force of the damper in the early stage of braking is immediately maintained at a high damping force, and the damping force of the damper in the middle stage of braking is variably controlled in multiple stages. This makes it possible to solve the conflicting problems of nose dive and ride comfort control at the same time.

In other words, even when using a reed switch-type vehicle speed sensor with low accuracy, the damper is immediately held at a high damping force that corresponds to the vehicle speed as soon as the brake switch is closed, effectively preventing sinking during the early stages of braking. . Furthermore, during the middle stage of braking, the damping force of the damper can be controlled in multiple stages, making it possible to control the suspension with good riding comfort and driving stability.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of a variable suspension device for a motorcycle according to the present invention, FIG. 2 is a flowchart for explaining the operation of a control circuit used in the device of the embodiment, and FIG. FIG. 2 is a schematic diagram showing an example of a damper with a variable damping force mechanism used in the same example device. FIG. 4 is a waveform diagram for explaining the operation of the variable suspension device for a motorcycle according to the present invention. 1...Vehicle speed sensor 2...Buffer 3...
・Brake switch 4...Buffer 5...Microcomputer 6...Drive circuit 7...Drive unit 10...
・Damper 11... Cylinder 15... Piston 22... Plunger 23... Orifice Patent applicant Suzuki Motor Co., Ltd. agent Patent attorney Inoro Groove piece 1 Figure 22 Figure 3 Figure 4

Claims (1)

[Claims] In a variable suspension device for a motorcycle equipped with a damper having a variable damping force mechanism, a vehicle speed sensor detects the traveling speed of the motorcycle and outputs a vehicle speed signal;
A brake switch that outputs a brake signal when the brake is applied, and a brake switch that immediately holds the damper at a high damping force for a certain period of time when the brake signal is received, and then a deceleration calculated from the vehicle speed signal. a damping force control circuit that generates and outputs a damping force variable signal that controls the damping force in multiple stages corresponding to the damping force and maintains the previous damping force for a certain period of time when the brake signal disappears; A variable suspension device for a motorcycle, comprising: a drive section that drives the variable damping force mechanism according to a variable signal.