JPS6245091B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a suspension control device that changes suspension characteristics in accordance with the driving state of an automobile or in accordance with manual operation.

(Prior art) The spring constant of the springs and the damping rate of the damper that make up the suspension of an automobile, in other words, the suspension characteristics, significantly affect the ride comfort and body posture of the automobile. For example, if the suspension characteristics are hard, the If it is too soft, the vehicle body will pitch or roll when braking or turning, making the vehicle's posture extremely unstable.

For such problems, for example, Japanese Patent Application Laid-open No. 1983-
Publication No. 30818 discloses an invention related to a "vehicle anti-roll device." This operates the orifice control solenoid of the shock absorber according to the vehicle speed and steering angle to increase the damping rate of the shock absorber during turning. According to this, during normal driving, the suspension characteristics are set to be soft to provide good riding comfort, and during cornering, the suspension characteristics are set to be hard to prevent rolling of the vehicle body.

By the way, as mentioned above, variable control of the suspension characteristics of the suspension, especially the damping rate of the damper, is usually performed by controlling the opening and closing of an orifice, as shown in the above-mentioned publication, and the actuator is a reversible control. A motor or a rotary solenoid is used, and by switching the direction of energization of these electromagnetic means, the orifice is opened and closed, and the suspension characteristic is switched between a soft state and a hard state. For this reason, this type of suspension control device is equipped with a changeover switch that changes over the energization path to the electromagnetic means.

However, in the past, the switching operation of the changeover switch also controls the supply and cut-off of drive current to the electromagnetic means, and therefore, this type of changeover switch has a contact point that cannot be used for repeated power supply and cutoff operations. This required a relatively large and therefore expensive transfer switch with sufficient capacity. In particular, multiple switches are required when controlling the front suspension and rear suspension independently, or when controlling each of the four front, rear, left and right suspensions independently. will be extremely expensive.

(Object of the Invention) The present invention addresses the above-mentioned circumstances in suspension control devices, and enables the use of low-cost switches with small contact capacity as multiple changeover switches for switching the energization paths to electromagnetic means. The purpose of this is to reduce the cost of this type of suspension control device.

(Configuration of the Invention) A suspension control device according to the present invention is configured as follows to achieve the above object.

That is, a suspension device with variable suspension characteristics, a plurality of electromagnetic means for changing the suspension characteristics of the suspension device, and a plurality of electromagnetic means for switching the energization path to each of the electromagnetic means in response to a suspension characteristic designation signal issued from a controller. a changeover switch means;
The main switch means is provided on the power supply circuit to each changeover switch means and is turned from OFF to ON after a certain delay time from the change of the suspension characteristic designation signal. According to such a configuration, the switching operation of each of the changeover switch means is performed with the main switch means in an OFF state, that is, in a non-energized state, and after the changeover operation of the changeover switch is completed, the main switch means is turned ON. After that, a driving current in a predetermined direction is supplied to the electromagnetic means via the changeover switch. Therefore, by providing only one main switch means having a relatively large contact capacity, it is possible to reduce the size and capacity of a plurality of changeover switch means, which are required.

(Example) The present invention will be described below based on an example shown in the drawings.

As shown in FIG. 1, a suspension device 2...2 that suspends the front, rear, left and right wheels 1...1 of the vehicle body is as follows:
A coil spring 3 and a damper 4 with variable damping rate, respectively.
and a motor 5 that changes the damping rate of the damper 4. On the other hand, a control device 6 is provided which sends a drive signal A to the motors 5...5 of each suspension device 2...2. and a signal C indicating the driving state of the automobile from the driving state detection sensor 8 are inputted. Here, the mode selection switch 7 has a function of switching the damper 4 between an automatic control mode and a manual control mode, and a function of switching the damper damping rate in the manual control mode. , for example, a vehicle speed sensor, a steering angle sensor, a brake sensor, etc.

Next, the specific structure of each of the above suspension devices 2 will be explained with reference to FIG. It has a piston case 15 to which a wheel is attached via a bracket 14, and into which the piston rod 13 is vertically slidably inserted, and the piston rod 13 and the piston case 15 have spring receiving members 16 and 17, respectively. The coil spring 3 is fixedly installed between both spring receiving members.

The piston case 15 is composed of an outer cylinder 18 and an inner cylinder 19, and a main valve 20 provided at the lower end of the piston rod 13 is fitted into the inner cylinder 19, so that the inner cylinder 19 has an upper part. Room 21
and a lower chamber 22, and the inner cylinder 1
The space between 9 and the outer cylinder 18 is a reservoir chamber 23. This reservoir chamber 23 is located at the upper end of the inner cylinder 1.
It communicates with an upper chamber 21 within the chamber 9, and its lower end communicates with a lower chamber 22 via a bottom valve 24 having an orifice.

On the other hand, the main valve 20 has an extension side orifice 26 configured to allow the working fluid to pass only from the upper chamber 21 to the lower chamber 22 side by means of a check valve 25, as shown in an enlarged view in FIG. A contraction side orifice 2 configured to allow working fluid to pass only from the lower chamber 22 to the upper chamber 21 side by a check valve 27.
8 and is further provided with an orifice valve 31 comprising a sleeve 29 and a valve body 30 rotatable within the sleeve 29. This orifice valve 31 is rotated by a control rod 32 inserted into the piston rod 13 by the motor 5 shown in FIGS. A state in which the through hole 29a and the through hole 30a in the valve body 30 are in communication, and both the through holes 29a and 30 shown in FIG.
A can be switched to a state where it is cut off. As a result, the damper 4 configured by the upper chamber 21, the lower chamber 22, and the main valve 20
However, there is a state in which the upper chamber 21 and the lower chamber 22 are communicated only by the orifice 26 or 28 and the damping rate is large, that is, a hard state. Even when the damping rate is communicated, the damping rate is switched to a small state, that is, a soft state.

Further, to explain the configuration of the control device 6 with reference to FIG. 5, the control device 6 includes a determination circuit 41, two switching relays 42 and 43 for front suspension and rear suspension, and a switching relay for these. One main relay 45 is provided on the power supply circuit 44 of the relays 42 and 43. The determination circuit 41 receives signals B and C from the mode selection switch 7 and the driving state detection sensor 8, and determines the suspension characteristics of the front and rear suspensions corresponding to the instructed mode or the detected driving state of the vehicle. It outputs suspension characteristic designation signals E and F that respectively indicate the determined suspension characteristics, and also outputs a predetermined delay time t ₁ (see Fig. 7) when at least one of these signals E and F changes. It is designed to output an energization signal G. Here, the energization signal G acts to close the main relay 45 by igniting the transistor 46 and energizing the coil 47 when turned on. Further, the suspension characteristic designation signals E and F are set to a high level to designate a hard suspension characteristic, and to a low level to designate a soft suspension characteristic. Excite. On the other hand, the switching relays 42, 43
have power supply side switches 42a, 43a and earth side switches 42b, 43b interlocked therewith, and each switch 42a, 42b, 43a, 43b is used to de-energize the coils 50, 51 as shown in the figure.
The soft side contacts _a1 ... _a4 are connected, but the hard side contacts _b1 ... _b4 are connected when the coils 50, 51 are energized. Then, in the switching relay 42 (the same applies to the switching relay 43), the power side switches 42a, 43a's hard side contacts b ₁ , b ₃ and the ground side switch 42b,
The soft side contacts a ₂ and a ₄ of 43b are connected to the two motors 5 for the front suspension (the switching relay 43 is for the rear suspension) via the diodes 52 and 53 and the limit switch 54, respectively.
5, and the soft contacts a ₁ and a ₃ of the power switches 42a and 43a and the hard contacts of the ground switches 42b and 43b.
b ₂ and b ₄ are connected to the other input terminal 5'' of the two motors 5, 5.

Here, the limit switch 54 is integrated into the motor 5 as shown in FIG. 2, and rotates integrally with a fixed disk 55 fixed in the case 5a of the motor 5 and the rotor 5b of the motor 5. As shown in FIG. 6, the movable disk 56 is provided with band-shaped contacts 56a, 56b arranged in the circumferential direction thereof, and the fixed disk 55 is provided with band-shaped contacts 56a, 56b.
For example, brush-like contacts 55a, 55 in contact with
b, 55c are provided. One strip contact 56b and a corresponding third contact 55c
It is arranged so that it is in constant contact with the
The other band-shaped contact 56a and the corresponding first and second contacts 55a and 55b are connected to a movable disk 56.
One of the contacts 55a or 55b is arranged so as to separate from the strip contact 56a at both stroke ends of the rotation range. In addition, the movable disk 56 rotates integrally with the rotor 5b of the motor 5, and the rotor 5b and the valve body 30 of the orifice valve 31 in the damper 4 are connected to the control rod 32.
Since the movable disk 5 is connected via
6 and the valve body 30 always correspond in position,
As shown in FIGS. 4 and 6, when the through holes 29a and 30a in the orifice valve 31 are communicated with each other, the second contact 55b separates from the strip contact 56a, and from this state, the valve body 30 and the movable disk 56 rotates at a certain angle in the x direction and the orifice valve 3
When the first through hole 29a, 30a is blocked, the first contact 55a separates from the strip contact 56a.

Next, the operation of the above embodiment will be explained.

Now, for example, the mode selection switch 7 shown in FIG.
is set to the automatic control mode, and the driving condition of the vehicle detected by the driving condition detection sensor 8 is such that the suspension characteristics of each suspension device 2...2 should be softened, or if the above-mentioned mode is selected. Assuming that the switch 7 is set to the soft side in the manual control mode, the determination circuit 41 of the control device 6 receives signals B and C from the switch 7 and the sensor 8 as suspension characteristic designation signals E and F. It outputs a low level signal that instructs the software. Therefore, the transistor 48,
49 and coils 50, 51 are both in the OFF state, and the switches 42a, 42b, 43a, 43b in the switching relays 42, 43 are all connected to soft side contacts _a1 to _a4 . At this time, in each suspension device 2...2, the through hole 29a of the orifice valve 31 in the damper 4,
30a are in a communicating state as shown in FIG. 4a, and the suspension characteristic (damping rate) of the damper 4 is in a soft state.

However, if the driving condition of the vehicle changes from this state to a state where the suspension characteristics should be set to hard in both the front and rear, or if the mode changeover switch 7 is set to the hard side in the manual control mode, then at the same time, the control device 6 Suspension characteristic designation signals E and F outputted from the determination circuit 41 in are switched to high-level signals instructing hardware, and accordingly, transistors 48 and 49 are turned on and coils 50 and 51 are excited. , switching relays 42, 43
Each switch 42a, 42b, 43a, 4 in
As shown by the dotted line, 3b connects the hard side contacts b ₁ ~
b Switch to the state where ₄ is connected. However, at this point, since the main relay 45 on the power supply circuit 44 of the switching relays 42, 43 is open, the driving current is not supplied from the switching relays 42, 43 to each motor 5...5. ...The suspension characteristic switching operation in step 5 is not performed.

However, as shown in FIG. 7, when a certain delay time t ₁ (for example, 10 ms) has elapsed from the time when the suspension characteristic designation signals E and F change, the energization signal G is output from the determination circuit 41 of the control device 6. The main relay 45 is closed by igniting the transistor 46 and energizing the coil 47. Therefore, the switching relays 42 and 43 are connected via the power supply circuit 44.
Power source side switches 42a and 43a are connected to a power source 57. At this time, since the limit switch 54 in each motor 5...5 is in a state where the first contact (contactor) 55a is connected as shown in FIGS. 5 and 6a, the main relay 4
5, one of the motors 5...5 through the hard contacts _b1 , _b3 of the power supply side switches 42a, 43a in the changeover relays 42, 43, the diode 52 on the motor 5...5 side, and the first contact 55a of the limit switch 54. The circuit leading to the terminal 5' is connected, and the other terminal 5'' of the motor 5...5 is connected to the switching relay 4.
Earth side switches 42b, 43 in 2, 43
It is connected to the ground via the hard side contacts b ₂ and b ₄ of b. As a result, each motor 5...5 is energized in the X direction shown in FIG. It is rotated in the x direction from the state shown in figure a, and the through holes 29a and 30a are in a state where they are blocked, as shown in figure b.
Each damper 4...4 is switched to a hard state.
When this switching is completed, the first contact 55 of the limit switch 54 is opened as shown in FIG. 6b.
a is cut off, and power supply to the motors 5...5 is stopped. Further, as shown in FIG. 7, a set time t ₂ (e.g.
1s), the energization signal G turns OFF,
Main relay 45 is opened.

In this way, the suspension characteristics of each suspension device 2...2 are switched. In this case, first, the suspension characteristic designation signals E and F change, and the switching relays 42 and 43 operate in a de-energized state. After that, the main relay 45 closes and the switching relay 42,
43, the motors 5...5 are energized.

This operation is the same when the suspension characteristic designation signals E and F change from a high level state indicating hardware to a low level state indicating soft.
As shown in FIG. 7, after a predetermined delay time _t1 has elapsed after the change, the energization signal G that closes the main relay 45 is output. In this case, the current from the power source 57 is supplied to the main relay 45 and the switching relay 4.
Power supply side switches 42a and 43a in 2 and 43
terminal 5″ of motor 5 via soft side contacts a ₁ and a ₃ of
The other terminal 5' of the motor 5 is grounded via the second contact 55b of the limit switch 54, the diode 53, and the soft contacts _a2 , _a4 of the ground switches 42b, 43b of the switching relays 42,43. , a current flows through each motor 5...5 in the Y direction opposite to the above case, and the valve body 30 in the orifice valve 31 and the movable disk 56 in the limit switch 54 move in the Y direction shown in FIGS. 4b and 6b, respectively. rotated to

Further, the above operation is performed in the same way when only one of the suspension characteristic designation signals E and F is changed in order to change the suspension characteristic of either the front suspension or the rear suspension.

In addition, the energization signal G that is output after the suspension characteristic designation signals E and F change turns OFF when the set time _t2 has elapsed.
However, before the set time _t2 elapses, the suspension characteristic designation signals E and F change again and the switching relays 42 and 43 switch at the same time, and the relays 42 and 43 become energized. This will result in a switching operation. In response to this, for example, as shown in FIG. 8, after the suspension characteristic designation signals E and F change to high level and the energization signal G turns ON accordingly,
When there is a change in the state that should cause the suspension characteristic designation signals E and F to go low again before the set time _t2 has elapsed, the energization signal G is activated at the same time as this state change.
Return to OFF, then set time t ₃ (e.g. 10ms)
After , the specified signals E and F are changed to low level to operate the switching relays 42 and 43,
Alternatively, the designation signals E and F may be changed to low level at the same time as the state changes, the energization signal G may be turned off at the same time, and the switching relays 42 and 43 may be operated after the set time _t3 has elapsed. Then, if the energization signal G is output again after the delay time _t1 has elapsed after the switching relays 42 and 43 have switched, the initial objective will be achieved.

(Effects of the Invention) As described above, according to the present invention, in a suspension control device that variably controls the suspension characteristics of a suspension according to the driving state of the automobile or according to manual operation, an electromagnetic means for changing the suspension characteristics is provided. The changeover switch means for switching the energization path to the energized state operates in a de-energized state. As a result, for example, in the above embodiment, two switches (four switches are required), and when controlling the suspension characteristics for each of the front, rear, left, and right suspensions, four switches (eight switches are required). It becomes possible to use the required changeover switch means with a small contact capacity, which in turn reduces the cost of this type of control device. Further, by performing the switching operation in a non-energized state, wear and tear on the contacts of the changeover switch means is reduced, and durability and reliability are improved.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; FIG. 1 is a control system diagram, FIG. 2 is a vertical sectional view showing the specific structure of the suspension device, FIG. 3 is an enlarged longitudinal sectional view of the main parts, and FIG. Figures 4a and 4b are enlarged cross-sectional views showing the operation of the orifice valve taken along the line in Figure 3, Figure 5 is a circuit diagram showing the configuration of the control device, and Figure 6 is a circuit diagram showing the configuration of the control device.
Figures a and b are enlarged cross-sectional views taken along the line in Figure 2, showing the action of the limit switch, Figure 7 is a time chart showing one working state of the embodiment, and Figure 8 is a time chart showing another working state. It is a time chart diagram shown. 2... Suspension device, 5... Electromagnetic means (motor), 41... Controller (judgment circuit),
42, 43...Switching means (switching relay), 44...Power supply circuit, 45...Main switch means (main relay).

Claims (1)

[Claims] 1. A suspension device with variable suspension characteristics, a plurality of electromagnetic means that change the suspension characteristics of the suspension device, and a plurality of electromagnetic means that switch energization paths to each of the electromagnetic means in response to a suspension characteristic designation signal issued from a controller. Suspension control of an automobile, comprising a changeover switch means and a main switch means provided on the power supply circuit to each changeover switch means and turned from OFF to ON after a certain delay time from the change of the suspension characteristic designation signal. Device.