JPH03208719A - Apparatus for adjusting vehicle floor height - Google Patents

Abstract

PURPOSE:To enable highly accurate control of a vehicle floor height by setting either a high or a low position sensor at a target vehicle floor height control level and providing a flip-flop circuit wherein a drop or a rise control signal is made a set signal and a rise or a drop control signal is made a reset signal. CONSTITUTION:A rise control signal from a vehicle floor height sensor is input to an input terminal 12 and a drop control signal is input to an input terminal 13, respectively. When a target vehicle floor height set level is set on the side of a lower limit position sensor position S2 and a vehicle floor height is at a higher level than it, an FF circuit 16 is set by the drop control signal input to the input terminal 13, and a drop valve 11 is opened by an output of an AND gate 15. Thus the vehicle floor height is lowered, and when the height comes across a high position side sensor position S1, the drop control signal to the input terminal 13 is eliminated, while the drop valve 11 is maintained in its driven state, and when the height reaches the sensor position S2 and the rise control signal is input to the input terminal 12 to reset the FF circuit 16, the valve is closed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vehicle height adjustment device that improves the accuracy of vehicle height adjustment.

Traditionally, vehicle height has been adjusted in motorcycles and other vehicles according to changes in the rider's weight, sitting height, road surface conditions, or payload, to improve riding comfort, optimize riding posture, and improve handling. In order to improve this, for example, a vehicle height adjustment device as shown in FIG. 1 has been proposed. Regarding this, when a signal instructing vehicle height adjustment is input to the control circuit 2 from the input terminal l, the vehicle height sensor 3
When it is determined that the vehicle height is below the set reference level, the output of the vehicle height sensor 3 is also input to the control circuit 2 via the circuit 4, and current is passed from the control circuit 2 to the vehicle height raising valve 5. . For this purpose, compressed air is supplied from a compressor 7 driven by a motor 6 to an air suspension 9 via an accumulator 8 and the lifting valve 5. Therefore, the air suspension 9 extends and the vehicle height sensor 3 also extends, and when the vehicle height rises to the set reference level, the vehicle height sensor 3 outputs a rising stop instruction signal to the control circuit 2. The control circuit 2 stops the operation of the lifting valve 5. Conversely, when the vehicle height sensor 3 determines that the vehicle height is equal to or higher than the set reference level, current is applied to the lowering valve 11 through the circuit 10 and the control circuit 2, and the valve l1 is opened. Therefore, the air inside the air suspension 9 is removed, and the vehicle height is lowered. The vehicle height sensor 3 detects that the vehicle height level has reached the set reference level due to this lowering, and the control circuit 2 stops energizing the lowering valve l1. By the way, such a vehicle height adjustment device has hysteresis in its spring characteristics (one stroke of load) due to the friction of the air sensor and suspension 9 itself, so the device stops when adjusting from a high vehicle height level. Even if the stroke position and the stroke position at which the vehicle stops when adjusting from a low vehicle height level are the same, a difference will occur in the compressed air pressure of the air suspension, making it impossible to properly adjust the vehicle height.

At the same time, vehicle height sensors are installed at two positions, vertically and at appropriate intervals, to control the vehicle so that it follows the appropriate target level within this range, so if the vehicle height is adjusted from a high level, the vehicle will stop. There is always a difference between the stroke position where the vehicle height is adjusted and the stroke position where it stops when adjusting from a low vehicle height level, and it is not determined where between the two high and low sensor positions the vehicle height is adjusted.This may be the cause of the hysteresis mentioned above. Combined with this, accurate vehicle height adjustment becomes impossible.

In other words, there was a drawback that the accuracy of vehicle height adjustment became extremely poor.

The present invention eliminates such drawbacks, and has two high and low
A sensor is provided to detect the vehicle height level at a position, one of the positions is set as a vehicle height control target level, and a rise control signal or a fall control signal is set as a set signal to a vehicle height rise control circuit or a fall control circuit. By connecting a flip-flop circuit (holding circuit) that operates using the descending control signal or the ascending control signal as a reset signal, the descending control signal or the ascending control signal emitted from each sensor at the two height positions marked E is insensitive between the sensors. Try to keep it even in the band,
When adjusting the vehicle height, the vehicle height is moved above or below the set target level, and then the vehicle height is adjusted again toward the set target level. A vehicle height adjustment device is proposed in which the accuracy of vehicle height adjustment is improved by terminating the adjustment operation.

Embodiments of the present invention will be specifically described below with reference to the drawings. FIG. 2 shows a control circuit for the vehicle height raising valve 5 and lowering valve II in the vehicle height adjustment system similar to that shown in FIG. An input terminal such as a power source, l2 is an input terminal for a rise control signal connected to the circuit 4 from a lower limit position sensor forming the vehicle height sensor 3, and l3 is an upper limit position sensor forming the vehicle height sensor 3. A manual terminal for a lowering control signal is connected to the circuit 10, and a control signal for raising or lowering the vehicle height is supplied from a vehicle height sensor to both input terminals. 14, Is is an AND gate, and one input terminal of each of these is connected to the input terminal 1, and the other input terminal of the AND gate 14 is connected to the input terminal 1.
2 is set to the other input terminal of the AND gate 15.
An input terminal l3 is connected via a reset type flip-flop circuit l6. Further, each drive circuit 17. is connected to the output side of each AND gate 14, ts. The vehicle height raising valve 5 and the vehicle height lowering valve l1 are connected via 18, respectively.

In such a circuit, an instruction signal for adjusting the vehicle height is input to the input terminal l? In the case where the vehicle height is input as shown in FIG. 3(a), if the set target level Ls is set at the lower sensor position S2, the vehicle height is set at a higher level L. , the input terminal 13 is input from the high position side sensor (not shown) in the vehicle height sensor.
A signal to lower the vehicle height f is input as a set signal S. Therefore, the state of the flip-flop circuit l6 is reversed. Drive circuit 18 based on the output of AND gate l5
The lowering valve 1l is driven. Thus,
As in the case explained with reference to FIG. 1, the air in the air suspension 9 is removed and the vehicle height is lowered, and when the vehicle height exceeds the high position sensor position MS■, the lowering control signal to the input terminal 13 is stopped. Ru. However, since the flip-flop circuit 16 still maintains the inverted state, the lowering valve 1l continues to be driven and the vehicle height continues to lower. However, as soon as the low position sensor position S2 set as the set target level Ls is reached, this low position sensor (not shown)
Since the height increase control signal is inputted to the input terminal l2, the flip-flop l6 goes into a reset state at the same time as this input of the increase control signal, and the lowering valve l1 is closed. At this time, even if the descending valve l1 is closed,
Due to the effects of air suspension friction, descending motion inertia, etc., the actual stopping position is slightly lower than the control target level Ls (dotted line area in the figure). The E rise control signal is input, and the drive circuit 17 drives the rise valve 5 based on the output of the AND gate 14.
By opening this valve 5, the compressor 7
Air is forced into the air suspension 9 and the vehicle height increases. When the vehicle height control starts to rise in this way, the vehicle height reaches the set target level L. As soon as the position S2 of the low-position sensor (not shown) is reached, the low-position sensor cuts off the raising control signal to the input terminal l2, and the vehicle height is maintained above the level L5. .

On the other hand, when inputting an instruction signal for vehicle height adjustment,
When the vehicle height is at level 1, L, which is below the set target level Ls, the vehicle height from the low position sensor (not shown) in the vehicle height sensor is inputted to the input terminal l2 as a raising control signal, and the vehicle height is raised. The raising valve 5 is opened in the same manner as described above to supply air to the air suspension 9, and when the vehicle height reaches the set target level 1,s, the driving of the raising valve 5 is stopped in the same manner as described above. This causes the vehicle height to reach the set target level L. Or, it will be stopped and maintained in the vicinity above this point.

If the vehicle height is too high and you want to lower it,
Once the vehicle height has descended below the set target level Ls,
By raising the vehicle again, the adjustment operation can be completed in the same direction as in the case of raising the vehicle height when the vehicle height is too low. can be done. That is,
In this way, it is possible to eliminate the influence of hysteresis caused by the friction of the air suspension 9 when the vehicle height is raised and lowered, and the vehicle height adjustment error can be reduced.

q In the embodiment shown in FIG. 3(a), the low sensor position S2 of the two vehicle height detection sensors is set to the set target level L. We have described a system in which, when the vehicle height is too high, the vehicle height is reversed and raised from below the set target level L8 and then adjusted and maintained at the level L5. As shown, the high sensor position S1 of the two high and low vehicle height detection sensor positions is set as the set target level L3, and the flip-flop circuit 16 is connected only between the input terminal 12 and the AND gate l4. By configuring the system to be reset by the lowering control signal of the input terminal l3, if the vehicle height is too low, the vehicle height is raised to a set target level L8 or higher and then lowered.
The configuration can be configured and implemented so that the vehicle height is adjusted to the set target level Ls, and when the vehicle height is too high, the adjustment is made toward the set target level Ls by a lowering control signal from only the high position sensor. .

FIG. 4 shows another example of the control circuit. This is basically the same structure as the one shown in Figure 2, but instead of manipulating the input signal of the input terminal l at the start and completion of each time vehicle height adjustment is necessary. - Once the input signal is input to the input terminal, it will automatically turn off at the same time as the vehicle height adjustment control is completed, and the timer will hold either the lowering or raising operation during vehicle height adjustment to maintain the set target level. A flip-flop circuit 19 for maintaining the operation of the ascending valve 5 and descending valve 11 is interposed between the input terminal 1 and the AND gates 14 and 15. When the control signal for raising the vehicle height is cut off, or when the output of the timer circuit 20 connected to the output side of the flip-flop circuit 19 is cut off, this flip-flop circuit 19 outputs a signal via the OR gate 2■. It is designed to be reset. A detection circuit 22 detects that the signal for raising the vehicle height is cut off, and is connected to the input terminal 12 and one of the input terminals of the OR gate 21. 23 is input terminal l2
This is a timer for stabilizing the control of the present invention l1 by inserting it between the control signal and the AND gate 14 and delaying the rise control signal.

In this control circuit, when a signal instructing the adjustment of the vehicle height is input to the input terminal l, the signal is sent to the AND gate 14 through the flip-flop circuit 19. An operation signal is input to 15 and timer 20. At this point, the timer 20 starts operating, but if the vehicle height adjustment signal is not input within a certain period of time, the flip-flop circuit 19 is reset to stop the adjustment operation. Now, as shown in FIG. 3(C), the lower position side sensor position MS2 is set to the set target level 1,s, as in FIG. 3(a) above.
Assuming that the vehicle height is at a level equal to or higher than the set target level L5, the height 2 is set as in the case of the control shown in FIG.
High position sensor among the vehicle height detection sensors (not shown)
From there, a control signal for lowering the vehicle height is input to the drive circuit 18 through the input terminal 13, the flip-flop circuit 16, and the AND gate in sequence, and the lowering halve 11 is opened. Therefore, as described above, the air in the air suspension 9 is removed and the vehicle height is lowered. Then, even if the vehicle height becomes lower after passing the set target level (.q) and the lowering control signal from the higher position sensor is cut off, the lowering is continued within a predetermined range, that is, for the timer set time. Continue.Here, when the vehicle height reaches a certain level L'L determined by the timer 23 below the set target level Ls (this is an active overslide part necessary for stable control). , the low position side detection sensor outputs a vehicle height raising control signal to the terminal l2.Therefore, the flip-flop circuit 16 is reset, the lowering signal circuit is cut off, and the lowering valve 1l is closed. After a delay caused by the timer 23, a vehicle height increase control signal is input, and after the lowering valve 1l is securely closed, a vehicle height increase control signal from the input terminal 12 is input to the drive circuit 17 to raise the vehicle. Thus, when the vehicle height rises and reaches the set target level L8, and the vehicle height increase control signal at terminal l2 is cut off, the vehicle height stops at or near that level Ls. At the same time, the operation of the flip-flop circuit 19 is reset via the detection circuit 22l3 and the OR gate 21.The signal for adjusting the vehicle height is then automatically turned off and the vehicle height adjustment is terminated. .

- On the other hand, when the vehicle height is below the set target level L8, the low position sensor (not shown) generates an elevation control signal, which is input to the input terminal 12 and is activated by the timer 23. After a short set time (usually about 1 to 2 seconds), the signal is input to the drive circuit 17 via the AND gate 14, and the lift valve 5 is opened to raise the vehicle height.When the vehicle height reaches the set target level L8, the above-mentioned The rise control signal from the low position sensor is cut off, and the detection circuit 22 detects this and resets the flip-flop l9, bypassing the timer 23 and cutting off the output of the AND gate 14, and the rise valve 5 is immediately turned off. When closed, the vehicle height stops increasing at the set target level Ls.

Note that the timer 20 is activated when the vehicle height cannot be raised to the set target level due to equipment damage such as a broken hose or a malfunction of the compressor. Since the solenoid of the compressor and the lift valve will remain in the operating state forever if the
This is effective when reversing the gate l4 and preventing an accident such as burnout of the solenoid due to continued energization of the solenoid of the lift valve 5 for a long time.

As described in detail above, according to the present invention, a sensor detects the vehicle height level at two high and low positions, and a vehicle height increase control signal and a vehicle height decrease control signal are respectively transmitted based on the output of the sensor. an air source that supplies compressed air to the air suspension via the vehicle height raising valve; and an air source that supplies compressed air to the air suspension via the vehicle height lowering valve. and an exhaust passage for discharging the air in the air suspension, wherein one of the two sensor positions is set to a vehicle height control target level, and the l5 control is performed. By providing in the circuit a set/reset type flip-flop circuit that operates using the falling control signal or rising control signal as a set signal and operating the rising control signal or falling control signal as a reset signal, it is possible to reach the set target level. When moving the vehicle height towards the target level, the direction in which the control operation ends is fixed, so that even if the vehicle height is above or below the set target level, the control operation will not reach any of the set target levels. Vehicle height adjustment can be performed with high precision.

[Brief explanation of drawings]

Figure 1 is a schematic system diagram of a conventional vehicle height adjustment device, Figure 2 is a control circuit diagram of a vehicle height adjustment device according to the present invention, and Figure 3 (
a) (b) is an explanatory diagram of the vehicle height adjustment operation by the control circuit of FIG. 2, FIG. 3(C) is an explanatory diagram of the vehicle height adjustment operation by another control circuit embodiment, and FIG. Another example will be shown. 2... Control circuit, 3... Vehicle height sensor, 5... Valve for ascending, 7... Air source, 9... Air suspension, 11-... Valve for descending, l2... 16 input terminals for rising control signals, l3... input terminals for falling control signals, l6... flip-flop circuits, 17, 18... valve drive circuits. l 7

Claims (1)

[Scope of Claims] A sensor that detects the vehicle height level at two high and low positions, and a vehicle height raising control signal and a vehicle height lowering control signal based on the output of the sensor, respectively, to a vehicle height raising valve and a vehicle height lowering valve. a control circuit that selectively supplies compressed air to each drive circuit; an air source that sends compressed air to the air suspension through the vehicle height raising valve; and an air source that supplies air within the air suspension through the vehicle height lowering valve. In a vehicle height adjustment device comprising an exhaust passage for discharging,
One of the two high and low positions of the sensor is set to the vehicle height control target level, and the lowering control signal or the lowering control signal is set as a set signal in the control circuit, and the lowering control signal or the lowering control signal is set in the control circuit. A set/reset type flip-flop circuit that operates as a reset signal is provided so that the lower control signal or the higher control signal is held even in the dead zone between the two sensors, and the above setting is maintained even when adjusting the vehicle height, whether high or low. A vehicle height adjustment device characterized in that the adjustment operation is completed from the same direction with respect to a target level.