JPS62191210A - Stabilizer control device - Google Patents

Abstract

PURPOSE:To reconcile rolls upon turning and a drive comfortability during rectilinear travel and to enhance the mountability of a suspension unit, by controlling the stroke of a cylinder unit for changing the coupling distance between an unsuspended member and a stabilizer in accordance with the vehicle speed, the steering angle and the steering angle rate. CONSTITUTION:When detection signals from a vehicle speed sensor and a steering sensor are delivered to a speed signal generating means E1 and a steering angle signal generating means E2, respectively, a vehicle speed signal and a steering angle signal are delivered to an operating means E3 and a steering angle speed signal generating means E3 computes a steering angle rate so that a steering angle rate signal is delivered to the operating means E4. The operating means E4 selectively and variably controls the stroke of a cylinder unit D to the neutral position of the piston, stepped stroke positions, all stroke positions in accordance with the inputted signals of vehicle speed, steering angle and steering angle rate. With this arrangement it is possible to reconcile rolls upon turning and the drive comfortability during rectilinear travel.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a stabilizer device that connects wheel-side unsprung members (for example, suspension arms) of left and right wheels of an automobile.

[Conventional technology].

2. Description of the Related Art Conventionally, stabilizer devices have been attached to left and right suspension arms, respectively, and are used as devices that reduce tilting and shaking of a vehicle when turning, etc., by connecting the independent left and right wheel movements. That is, when the left and right wheels of the stabilizer device are in the same suspension position, no twist occurs in the stabilizer device, and there is no relation to each other's suspensions. If one of the left and right wheels goes over a protrusion, or if the suspension positions of the left and right wheels differ greatly during a turn, the torsion bar of the stabilizer device is twisted, and as a result, the torsional elastic force is applied in the direction to cancel this twisting due to the reaction of the torsion bar. This works to equalize the suspension position of the left stone wheel. The functions of this device are related to the vehicle's rolling characteristics and the road surface followability of the wheels, and it is difficult to achieve both, and as a result of some kind of compromise, both characteristics are fixed at specific levels.

Therefore, there has been a demand for a stabilizer device that can adjust the torsional elastic force depending on the driving condition. In other words, it was desired to reduce torsional rigidity by emphasizing road followability when driving in a straight line, and emphasize roll characteristics and increase rigidity when turning.

Conventionally, for example, as disclosed in Japanese Utility Model Application Publication No. 57-66009M, a hydraulic cylinder has been installed at the suspension arm attachment 81S of the stabilizer.

A mechanism in which the hydraulic chambers on the extension and contraction sides of the vehicle are communicated through a bypass passage, and a check valve that is opened and closed by the power steering (PS) hydraulic pressure is installed between the passages, and the torsional stiffness of the entire stabilizer system is changed by the PS hydraulic pressure. is proposed.

Problems to be Solved by the Invention This type of conventional device can change the 1-strain resistance of the piston inside the cylinder, but it only changes the torsional stiffness of the stabilizer, and the hydraulic cylinder unit It is not possible to actively prevent the vehicle from rolling by supplying pressure oil to the cylinder chamber of the vehicle.

In view of the above circumstances, the present invention provides a stabilizer control system that can achieve both roll when turning and ride comfort when going straight, is easy to mount on a vehicle, and is controlled according to vehicle speed and steering angular velocity. The purpose is to provide equipment.

[Means for Solving the Problems] The present invention, which has been made to achieve the above object, as shown in FIG.
In the vehicle connected by the above, the spring is interposed as a connecting means between at least one of each of the unsprung members B and the part of the stabilizer C that transmits and receives the torsional force, and the movement of the piston that slides in the cylinder causes the spring to move. Stabilizer control comprising a cylinder unit D that changes the connection distance between the lower member and a part of the stabilizer that transmits and receives torsional force, and a cylinder unit control means E that controls the stroke of the piston of this cylinder unit D. In the device, the cylinder unit control means E includes: a speed signal generation means E1 that generates a speed signal according to the running speed of the vehicle; and a steering angle signal generation means E2 that generates a steering angle signal according to the steering angle of the vehicle. , Based on the steering angle signal from this steering angle signal generating means,
Steering angular velocity signal generating means E3 that outputs a steering angular velocity signal
and, based on the speed signal, steering angle signal, and steering angular velocity signal, actuate screws 1 to 1 of the cylinder unit in a freely movable state, or move the piston to a neutral stroke position, a stepwise stroke position, or a full stroke position. The gist of the present invention is a stabilizer control device characterized by comprising: actuating means E4 for actuating the stabilizer.

[Function] In the stabilizer control device of the present invention, the torsional rigidity of the stabilizer is variably controlled by the stroke displacement of the cylinder unit, and is optimally set according to the stroke position, vehicle speed, steering angle, and steering angular velocity. The ride comfort can be improved when making slow or slow turns, while excellent responsiveness can reduce roll when making sharp turns at high speeds.

[Example] An embodiment of the present invention will be described below with reference to the drawings.

FIG. 2 is a diagram showing the front part of the vehicle, and the front wheel stabilizer 1A is rotatably supported by the vehicle body by rubber bearings 3a and 3b. One end 1a of the stabilizer 1A is
It is attached to a strut section (or suspension arm) 7a via a tie rod 5a, and the other end 1b is attached to a strut section 7b via a cylinder unit 9A.

13a and 13b are wheels, and lower arms 15a and 15b are attached to the vehicle body via slats 1 and 7a and 7b. As shown in FIG. 3, in the cylinder unit 9A, a piston 9b is slidably fitted into the cylinder 9a, and the piston 9b moves the inside of the cylinder 9a into an upper chamber 9e having ports 9c and 9d. It is divided into a lower chamber 9f, and a rod 9q is fixed to the piston 9b, and this rod 9q is fixed to the strut portion 7b. Therefore, the stabilizer device is configured such that the torsional rigidity of the stabilizer 1A can be varied by movement of the piston 9b of the cylinder unit 9A.

Stroke control of the cylinder unit 9A is performed by a hydraulic control device shown in FIG.

20 is driven by the engine, and through its output shaft 21.

Then, the hydraulic pump 22 is driven. The hydraulic pump 22 pumps oil from the reservoir 24 and supplies it to the front wheel cylinder unit 9A and the rear wheel cylinder via a pipe 32, a directional control valve (4-bottom, 3-position solenoid valve) 26, and pipes 33 to 36. While supplying pressure oil to 1 to 9B in 9a, the pipe line 32
, 37, pressure oil is also supplied to the power steering device 28.

The upper part 19e of both cylinder units 9A, 9B and the royal chamber 9f communicate with each other via an on-off valve (4-port solenoid valve) 42, and also communicate with the reservoir 24. In addition, the pipe line 34 to the rear wheel side cylinder unit 9B
．． 36 has an aperture 31a.

31b is provided to compensate for the rear wheel stabilizer (not shown) whose rigidity is set to be weaker than that of the front wheel stabilizer 1A.

A switching control signal is sent to the directional control valve 26 and the opening/closing valve 42 by an electronic control unit ff150 consisting of a microcomputer, etc., and the directional control valve 26 has a first position (neutral mode), a second position (extension mode), and a second position (extension mode). Third
position (reduction mode), while the on-off valve 42 is switched to communication mode and cutoff mode. Signals input to the electronic control device 50 include a steering sensor 60 that detects the steering angle, a vehicle speed sensor 62 that detects vehicle speed, and a stroke sensor 64 that detects the stroke of the piston 9b of the front wheel cylinder unit 9A. Based on the signal, a control signal is output according to a program built into the electronic control 8@50.

The electronic control device 50 includes an input section 51 for inputting a vehicle speed sensor 60, a steering sensor 62, and a stroke sensor 64, a CPU 52, a ROM 53 storing programs shown in FIG. 8, and a temporary storage means. It is composed of a RAM 54 and an output section 55.

Next, the operation of the stabilizer control device under actual driving conditions will be explained.

First, straight-ahead driving will be explained. When driving straight, the fourth
The directional control valve 26 in the figure is in neutral mode, and the on-off valve 4 is in neutral mode.
2 is set to communication mode (OFF state). As a result, pressure oil from the hydraulic pump 22 is supplied only to the power steering device 28 via the pipes 32, 37, and is not supplied to the cylinder units 9A, 9B.

On the other hand, since the on-off valve 42 is set to the communicating state (OFF state), the upper and lower chambers 9 of the cylinder units 9A and 9B
e, 9f communicate with each other via conduits 33-36, 38, and 39. Therefore, in this mode, the piston 9b
can move freely within the cylinder 9a, which means that the torsional force transmitted from the stabilizer 1 directly causes the pistons 9b of the cylinder units 9A and 9B to move, resulting in almost no torsional rigidity of the stabilizer. .

Next, when turning, when the steering angle and vehicle speed are small, the direction control valve 26 is held in the neutral mode, and the on-off valve 42 is kept in the cutoff mode (O
(N state). As a result, the cylinder unit 9
A, 9B piston 9b to neutral stroke position S < S
Fix in an oil-tight state at =O>. Therefore, the cylinder unit 9A.

Since the stabilizer 9B connects the stabilizer and the strut portions 7a and 7b as a kind of rigid body, the stabilizer 1 exerts its inherent torsional rigidity and stabilizes the running condition when the vehicle turns.

On the other hand, when turning right or left, if the steering angle or vehicle speed is large, the on-off valve 42 is placed in the cutoff mode (ON state).
At the same time, the directional control valve 26 is switched to the extension mode or the contraction mode.

That is, in the extension mode, the pressure oil of the hydraulic pump 22 is
Pipe line 32 → Directional control valve 26 → Pipe lines 35, 36, throttle 31
cylinder unit 9A via b.

The pressure oil in the upper chamber 9e is supplied to the royal room 9f of 9B, and the pressure oil in the upper chamber 9e is
3. Conduit 34. It is discharged into the reservoir 24 via the throttle 31a → direction control well 26 → power steering device 28. Then, when the electronic control device 50 determines that the cylinder units 9A and 9B have reached the target stroke position based on the detected value of the stroke sensor 64, the direction control valve 26 is switched to the neutral mode.
The pistons 9b of the cylinder units 9A and 9B are fixed in an extended state.

As a result, as shown in FIG. 5, torsional rigidity of the stabilizer 1 is actively generated in the vehicle, and the roll angle α of the vehicle is reduced.

On the other hand, in the reduction mode of the directional control valve 26, the hydraulic pump 2
2 pressure oil is transferred from pipe 32 → direction control well 26 → pipe 33.3
4. Pressure oil is supplied to the upper chamber 9e of the cylinder units 9A, 9B via the throttle 31a, and the pressure oil in the lower chamber 9f is supplied to the pipes 35, 36.
, throttle 31b → direction control valve 26 → conduit 37 → power steering device 28 → conduit 40 and is discharged into the reservoir 40. Then, similarly to the extension mode, the direction control valve 26 is switched to the neutral mode, and the pistons 9b of the cylinder units 9A and 9B are moved to the target stroke position S.
As shown in FIG. 6, the stabilizer 1 is set in a contracted state to actively generate torsional rigidity and reduce the roll angle α.

That is, as shown in FIG. 7, the roll angle ψ of the vehicle with respect to the lateral acceleration G during turning is determined by the cylinder unit 9A,
If cylinder unit 9B is movable, the line will be shown by the one-dot chain line a. If the cylinder units 9A and 9B are oil-tight and the stroke position is fixed at O, the line will be shown by the two-dot chain line a. In the case of displacement to the stroke position, the stroke position S roughly changes from 1/3 → 2/3 → 3 on the straight line C.
When the displacement is /3, the state is shown by the broken line.

Next, the operation of the stabilizer control device will be explained according to the flowchart of FIG. 8.

First, in steps 110 and 120, the vehicle speed sensor 6
2, the vehicle speed signal V and the steering angle signal θ are read from the steering sensor 62, respectively, and then step 1
30 is executed, and it is determined whether the turn is to the right or to the left based on the steering angle signal θ read in step 120, and if it is determined to be a right turn, step 1 is executed.
Proceed to 40. At step 140, a steering angular velocity signal S is calculated based on the steering angle signal θ. Steering angular velocity signal θ
is determined, for example, from the steering angle θ determined in the previous process and the processing time of this routine. Next, step 150
is executed, the map shown in FIG. 9 is read out, and it is determined to which region the vehicle speed signal V and the steering angular velocity signal θ belong, either the slow steering region A or the sudden steering region B. If it is determined that it is in region IIJ, A, the determinations in step 160 and step 170 are executed.

In other words, the map shown in FIG. 10 is read out, and area A1 is
~A4, it is determined which area it belongs to, and if it is included in each area,
Optionally proceed to steps 180-210. Here, in step 180, the pistons 9b of the cylinder units 9A and 9B are set to be movable, and in steps 190 to 210, the stroke positions S of the screws 1 to 9b are set to 1/3.2/3.
．． Set each to 3/3 (full stroke). At the stroke position S thus set in steps 180 to 210, the direction control valve 26 and the on-off valve 42 are controlled in step 220.

On the other hand, if it is determined in step 150 that the map in FIG. 9 belongs to the sudden steering region B, step 23
0, the map shown in FIG. 11 is read out, and it is determined whether the vehicle speed signal V and the steering angle θ belong to region B1 or region B2, and in the case of region B1, the cylinder unit Stroke position S of 9A and 9B is O
On the other hand, in the case of region B2, the piston 9b is set to move to the full stroke position 5 (S=111) (step 250). In addition, in Fig. 11, Fig. 11 (A
>, both steering angle θ and steering angular velocity θ are positive,
Fig. 11 (B) shows a state in which the steering angle is increased when turning to the right, the steering angle θ is positive, the steering angular velocity is negative, and a state in which the steering angle is increased when turning to the right, and Fig. 11 (C) shows a state in which the steering angle is The angle θ is negative and the steering angular velocity θ is positive, indicating a turning back state in a left turn. Indicates an increasing state.

The direction control valve 26 and the opening/closing control valve 42 are controlled in step 22, O so that the stop opening position S is set in steps 240 and 250.

On the other hand, if it is determined in step 1.30 that the turn is to the left, the determination process (
300), while the stroke position S is controlled to be set in the opposite direction.

Therefore, by implementing the flowchart as described above, the cylinder unit 9
A and 9B are controlled to be movable, or the stroke position S is controlled to be displaced stepwise to the entire stroke position.

In other words, in the case of the slow steering region Itj,A where the steering angular velocity θ is small, the stroke position S is finely controlled to set the optimum torsional rigidity of the stabilizer, and in the case of the steep steering region B where the steering angular velocity θ is large, the turning Fast stroke control is performed to follow the speed.

Therefore, according to this embodiment, the torsional rigidity of the stabilizer is optimally controlled regardless of the magnitude of the steering angle, steering angular velocity, and vehicle speed, so it is possible to improve ride comfort and reduce roll.

The time chart in FIG. 12 shows the relationship between the running state of a vehicle equipped with the above stabilizer control device and the stroke positions S of the cylinder units 9A and 9B. Now, from a right turn with a steering angle of 90 degrees at a vehicle speed of 40 km/h, the steering angle is 90 degrees.
To explain the case where a left turn is made, when the steering angle θ is increased at time t1, cylinder units 1 to 9A, 9
The stroke position S of B is displaced stepwise from 1/3 → 2/3 → 3/3, and then, when the handle is turned back at time t2, the stroke position S of cylinder units 9A and 9B is changed to
is returned and roughly starts turning left at time t3, cylinder unit 9A reverses to turning right.

Stroke position S of 9B is 11/3 → -2/3 on the contraction side
→ After the displacement of -3/3, the stroke S is returned to O.

[Effects of the Invention] As explained above, according to the present invention, the torsional rigidity of the stabilizer is optimally controlled regardless of the vehicle speed, steering angle, and steering angular velocity, thereby improving ride comfort and reducing roll. It is possible to reduce the

[Brief explanation of drawings]

Figure 1 is a configuration diagram showing an example of the basic configuration of the present invention;
3 is a sectional view showing the cylinder unit, FIG. 4 is a configuration diagram showing the stabilizer control device, and FIGS.
7 is a graph showing the relationship between lateral acceleration and roll angle, FIG. 8 is a flowchart showing control of the stabilizer, and FIGS. 9 to 11 are illustrations of the same embodiment. FIG. 12 is a graph showing the control characteristics of this embodiment, and FIG. 12 is a time chart showing the operation of the same embodiment. A... Wheel B... Unsprung member C... Stabilizer D... Cylinder unit E... Cylinder unit control means E1... Speed signal generation means E2... Steering angle signal generation means

Claims (1)

[Claims] In a vehicle in which unsprung members of left and right wheels are connected by a stabilizer, there is provided a connecting means between at least one of the unsprung members and a portion of the stabilizer that transmits and receives torsional force. A cylinder unit that changes the connection distance between an unsprung member and a part of the stabilizer that transmits and receives torsional force by the movement of a piston that slides within the cylinder; In the stabilizer control device, the cylinder unit control means includes: a speed signal generating means that generates a speed signal according to the traveling speed of the vehicle; A steering angle signal generating means for generating a signal, and based on the steering angle signal from the steering angle signal generating means,
a steering angular velocity signal generating means for outputting a steering angular velocity signal, and operating a piston of the cylinder unit in a movable state based on the speed signal, the steering angle signal and the steering angular velocity signal, or moving the piston to a neutral stroke position.
1. A stabilizer control device comprising: actuating means for actuating the stabilizer to a stepwise stroke position or a full stroke position.