JPS60244609A - Suspension of automobile - Google Patents

Abstract

PURPOSE:To improve responseability of suspension characteristics control, by supplying a driving signal for hardening suspension characteristics of a suspension device to an adjusting means when it is detected that a shift position is in a specific stage. CONSTITUTION:A suspension device 2 comprises a coil spring 3, damper 4 and air chamber 5. The damper 4 is selected to two stages by a step motor 6. The air chamber 5 is connected through a pipe 7 to an accumulator 8. An electromagnetic valve 9 is interposed between the air chamber 5 and the accumulator 8. The valve 6 and the motor 6 include respective adjusting means 10 for changing suspension characteristics of the device 2 and controller 11 for generating driving signals A and B as soft and hard signals, respectively. The controller 11 is designed to receive a pisition signal C from a shift position detecting sensor 12 for detecting that a shift position of a transmission is in a specific stage.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an automobile suspension, and more particularly to an automobile suspension in which suspension characteristics are variably controlled in accordance with driving conditions.

(Prior Art) It is already known that the spring constant of the springs and the damping force of the damper constituting the suspension of an automobile, that is, the suspension characteristics of the suspension, can be changed depending on the driving condition (for example, as disclosed in Japanese Utility Model Application No. 55-109008). Public bulletin). In the case of this known example, at high speeds, the suspension characteristics of the rear wheels are made relatively soft compared to the front wheels, and the steering characteristics are set to understeer characteristics, and at low speeds, the suspension characteristics are set to be hard, contrary to those at high speeds. By providing two-coatral steering characteristics and oversteer characteristics, straight-line stability at high speeds and turning maneuverability at low speeds can be simultaneously satisfied (7).

However, in order to improve the overall drivability and ride comfort of a car, changing the suspension characteristics depending on the vehicle speed as proposed above is insufficient, and the center of gravity of the car body changes during sudden starts etc. It is necessary to control the suspension characteristics in such a way that the influence of the applied acceleration is suppressed as much as possible.When controlling the suspension characteristics at the time of starting, it is necessary to control the suspension characteristics by detecting the vehicle speed as in the conventional method. , the responsiveness may deteriorate, and improvements in this respect are desired.

(Problems to be Solved by the Invention) The present invention has been made in an attempt to solve the problems pointed out in the above-mentioned section of the prior art. It is an object of this invention to make it possible to control the suspension characteristics with good responsiveness by controlling the suspension characteristics of the suspension device to be hard when the position is in a specific gear, for example, 1st gear.

(Means for Solving the Problems) As a means for achieving the above object, the present invention provides a suspension device with variable suspension characteristics, an adjusting means for changing the suspension characteristics of the suspension device, and a shift position that can be specified. In the suspension of an automobile, the controller is configured to receive an output signal from the knot position sensor and to detect whether the shift position is at a specific gear. When this is detected, a drive signal for hardening the suspension characteristics of the suspension device is output to the adjusting means.

(Function) In the present invention, an output signal from a shift position sensor that detects that the shift position is a specific gear is used to operate the adjustment means in a hard and gradual manner to adjust the suspension characteristics of the suspension device. The effect of improving the responsiveness of the suspension characteristic control of the suspension device using the vehicle speed detection method can be obtained. Furthermore, by making the suspension characteristics of the suspension device harder when the shift position is at a specific stage, it is possible to improve the ride comfort when there is a large change in acceleration, such as during a sudden start.

(Embodiments) Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

As shown in FIG. 1, each wheel 1 is provided with a suspension device 2 for suspending the vehicle body. Each of these suspension devices 2 is composed of a coil spring 3, a tamper 4, and an air chamber 5.
The attenuation rate can be switched in two stages with a configuration as will be described later, and a step motor 6 is provided as an actuator for performing the switching. Further, the air chamber 5 is connected to the accumulator 8 via a pipe 7, and a solenoid valve 9 is installed between the air chamber 5 and the accumulator 8 to disconnect communication between the two. The solenoid valve 9 and the step motor 6 act as adjustment means IO for changing the suspension characteristics of the suspension device 2. and,
A controller 11 is provided that outputs drive signals A and B, which are soft signals or hard signals, to the step motor 6 and the solenoid valve 9 in each suspension device 2, and the controller 11 is configured to control the shift position of the transmission. It is configured such that the position signal C from the shift position detection sensor 12 is manually input to detect that the gear is in a specific gear (in this embodiment, I speed as described later).

Here, the specific structure of the suspension device will be explained.

As shown in FIG. 2, the upper end of the suspension device 2 is fixed to the vehicle body via the mounting member I3 and the elastic body 14.
The upper case I5 forms the air chamber 5, and the lower case 16 is movable vertically relative to the upper case 15, and the lower end of the upper case I5 and the upper end of the lower case 16 are connected to each other. Both cases I5. are connected by a rolling diaphragm 17; + 6 is a sticker i
It is partitioned by iM'18. The lower case I6 is further composed of an outer cylinder 19 and an inner cylinder 20, and a piston rod 21 is inserted into the inner cylinder 20 so as to be relatively vertically slidable. The interior of the inner cylinder 20 is partitioned into an upper oil chamber 23 and a lower oil chamber 24 by a main valve 22 provided at the lower end. Further, a bottom valve 25 is provided at the lower end of the inner cylinder 20, and a space between the inner cylinder 20 and the outer cylinder 19 is a reservoir chamber 26.

Furthermore, the outer cylinder 19 rotatably supports a wheel by 4°.
A bracket 27 is provided for mounting the support mechanism.

As shown in an enlarged view in FIG. 3, the main valve 22 has an extension side orifice 29 formed by a check valve 28 to allow hydraulic oil to flow from the upper oil chamber 23 to the lower oil chamber 24 side. A contraction side orifice 31 is provided so that the check valve 30 allows hydraulic oil to pass from the upper oil chamber 23 only to the two-part oil chamber 24 side. These constitute a damper 4 that quickly damps vibrations between the upper case 15 and the lower case 16, that is, the vehicle body side and the wheel side.

The piston rod 21 of the damper 4 is hollow, and a control rod 32 is rotatably inserted into the piston rod 21 . This rod 32 is connected to the step motor 6 through a rotary key 33 engaged at two ends.
When the control rod 3 is rotated by
2, the valve body 33 provided at the lower end of the piston rod 2;
An orifice valve 35 is constituted by a valve case 34 provided at the lower end of the valve 1 . That is, as shown in FIG. 4, a passage 36 for communicating the upper oil chamber 23 and the upper end oil chamber 24 formed in the cylindrical valve case 34 is connected to the case 3.
The communication is interrupted by the rotation of the valve body 33 fitted in the valve body 4, or communicated through an orifice 37 provided in the valve body 337. As a result, the first oil chamber 23 and the upper oil chamber 24 are communicated only through the expansion orifice 29 or the contraction orifice 31 in the main valve 22, and in addition, through the orifice 37 of the orifice valve 35. is also switched to a connected state,
The damping rate of the damper 4 is switched to two levels, ie, a hard state and a soft state.

Further, as shown in FIG. 2, the upper case 23 and the lower case 24 are provided with spring receivers 38 and 39, respectively, and the coil spring 3 is installed between these, and the coil spring 3 is connected to the air chamber 5. The air inside constitutes the spring of the suspension device 2.

In this case, since the air chamber 5 is connected to the Akicomulator 8 via the above-mentioned U-like pipe 7 and the solenoid valve 9, the amount of air that acts as a spring when the solenoid valve 9 is closed and opened is is increased or decreased, thereby switching the spring constant of the spring into two levels of large and small, ie, a hard state and a soft state.

On the other hand, the shift position sensor 12 is installed in the transmission case 40 as shown in FIGS. 441
Is it like being pressed against this? , has been d. That is, when the soft rod 42 is displaced in the direction of the arrow by the control lever 45 (when a shift operation is performed from I speed to 2nd speed, or from 2nd speed to I speed), the operating plunger 4I of the sensor 12 operates, The sensor 12 is configured to emit a position signal C. In this embodiment, when the shift rod end 43 is displaced to the first gear position, the sensor 1
2, the position signal C is input to the controller 11. Note that the operation of the control lever 45 in the direction of arrow B is a selection direction operation.

The controller 11 operates a step motor 6 which acts as a suspension characteristic adjusting means IO of the suspension device 2 by human power using a position signal C (an output signal when the soft position or first gear is detected) from the shift position sensor 12.
It is configured to output a drive signal B to each of the electromagnetic valves 9 and 9 to reduce the damping rate of the damper 4 and to operate the air spring so that the spring constant is constant.

Next, the operation of the suspension of the illustrated automobile will be explained.

When the driver operates the transmission to set the soft position to 1st speed, a position signal C is input from the shift position sensor I2 that detects this to the controller 11, and based on the position signal C, the controller 11 changes the suspension device 2. A drive signal B, which is a hard signal, is output to the adjustment means 10. The drive signal B drives the step motor 6 and the solenoid valve 9, which act as the adjusting means 10, so as to set the suspension characteristics to a hard state. That is, by driving the step motor 6, the passage 36 of the orifice valve 35 is cut off, thereby reducing the damping rate of the damper 4, and by closing the solenoid valve 9, the spring constant of the air spring is increased. It is.

Therefore, at the time of starting, etc., the suspension characteristics of the suspension device 2 are in a hard state, so that the influence of acceleration can be suppressed as much as possible.

When the shift position is shifted to a position other than 1st speed, the position signal C from the shift position sensor 12 disappears, and the controller 11 outputs a soft signal drive signal /\ to the adjustment means 10 of the suspension device 2. The drive signal A
, the step motor 6 and the solenoid valve 9 are
is driven so that the suspension characteristics are in a soft state. That is, by driving the step motor 6, the passage 36 of the orifice valve 35 is brought into communication, and the damping rate of the damper 4 is increased. L-2 also, solenoid valve 9
By opening the air valve, the spring constant of the air valve becomes small.

In the embodiment described above, it goes without saying that the soft position of the specific gear detected by the soft position sensor 12 may be set to 1st speed, or that the specific gear may be set to another soft position.

(Effects of the Invention) As is already clear from the explanations in each of the above items, the automobile suspension of the present invention has the ability to switch the suspension characteristics of the suspension device to the heart state at the same time when the soft gear is entered into a specific gear, for example, I speed. As a result, there is no risk of delay in response even when starting suddenly, and there is an excellent effect that reliable suspension characteristic control can be performed and anti-scott measures can be taken.

In addition, since a soft position detection sensor that detects the shift position is used as a sensor for suspension characteristic control, vehicle speed
It also has the effect of being extremely simple compared to other methods.

[Brief explanation of drawings]

Fig. 1 is a system diagram of an automobile suspension according to an embodiment of the present invention, Fig. 2 is a vertical sectional view of the suspension device shown in Fig. Figure 4 is an enlarged cross-sectional view of the orifice valve in Figure 3, and Figures 5 and 6 are cross-sectional views of the mounting structure of the knot position detection sensor in Figure 1. 2... Suspension device 10... Adjustment means (step motor 6 and solenoid valve 9) 11... Roller 12... Shift position detection sensor/middle -IQ Noni suspension device 3 Coil spring ° Damper j Air chamber O ・Step motor (, il, ff adjustment 1s 10)
7, Pipe 9 ° Solenoid valve (1 purple adjustment means 10) //゛Con 1-Roller/2 Shift position detection sensor

Claims (1)

[Claims] 1. A suspension device with variable suspension characteristics, an adjustment device that changes the suspension characteristics of the suspension device, a shift position sensor that detects that the soft position is at a specific stage, and a controller that operates the adjustment device. and when the controller receives an output signal from the shift position sensor and detects that the shift position is a specific gear, the controller controls the adjustment means to harden the suspension characteristics of the suspension device. An automobile suspension characterized by being configured to output a drive signal.