JPS61268511A - Device for adjusting height of vehicle - Google Patents

Abstract

PURPOSE:To prevent a vehicle from traveling with an unusual vehicle height by providing a vehicle height restoring device and enabling the vehicle height to be restored to a standard height by means of manual operation or a detected signal from a travel condition detecting device, in a vehicle height adjusting means for a vehicle having an air spring. CONSTITUTION:At the time of a handling operation, the height of a vehicle is appropriately adjusted by means of an up button 42 and a down button 43, and a restore button 44 is pressed when the operation is completed. Thereupon, a microcomputer 40 read the output of a vehicle height sensor 56, compares it with a standard vehicle height, and controls an automatic intake valve 27 and an automatic exhaust valve 28 to obtain the standard vehicle height, while lighting a lamp 46. Even if a vehicle started traveling without carrying out restoring operation, when the inputted outputs of a vehicle speed sensor 52 is above a certain value, e.g., 20km/h or more and a gear position sensor 51 is above a second gear, the microcomputer 40 judges whether the vehicle height is at a standard value or not and, if it is not at the standard value, carries out control so as to restore it to the standard value. Thereby, traveling with an unusual vehicle height can be prevented.

Description

[Detailed description of the invention]

TECHNICAL FIELD The present invention relates to a height adjustment device for a vehicle, and in particular, at least a portion of a suspension spring is composed of an air spring, and the supply and discharge of air to the air spring is controlled by an electronic control device. The present invention relates to a height adjustment device for a vehicle, which adjusts the height by adjusting the height of the vehicle. KSummary of the Invention The present invention provides an automatic restoration means for restoring the height of the vehicle to the standard height, and when the automatic operation means is operated or it is detected that the vehicle is in a running state, the automatic restoration is performed. The height of the vehicle body is restored to the standard height by a means, and the vehicle is prevented from being driven in a state where the vehicle height is not appropriate. [Prior Art] By configuring at least a portion of a suspension spring from an air spring, it becomes possible to adjust the vehicle height or the height of the cargo platform by supplying and discharging air to the air spring. . Furthermore, by supplying and discharging this air using a magnetic valve, it becomes possible to adjust the height of the loading platform by electronic control. In addition, by opening and closing the above magnetic valve with a manually operated push button,
It becomes possible to easily load and unload cargo by changing the height of the loading platform to an arbitrary height and aligning the loading platform with the platform.

[Problems that the invention attempts to solve]

However, if you use this manual push button to change the height of the cargo platform to a different height from the standard height, the height of the stop lamp and tail light installed at the rear end of the cargo platform will change if you continue to drive in that state. There is a possibility that the height may deviate from the appropriate height. Furthermore, since the angle of the optical axis of the headlamp deviates from an appropriate angle, there is a possibility that driving at night may be hindered. The present invention has been made in view of these problems, and particularly when the vehicle height is at a position deviated from the standard height, the present invention promptly restores the standard state to allow normal driving. It is an object of the present invention to provide a height adjustment device for a vehicle that makes it possible to adjust the height of a vehicle.

[Means to solve the problem]

The present invention provides a vehicle in which at least a portion of a suspension spring is an air spring, and the height is adjusted by controlling the supply and discharge of air to the air spring by an electronic control device. An automatic restoring means for restoring the height to the standard height is provided, and the automatic restoring means restores the vehicle height to the standard height in response to the operation of the manual operation means or the detection by the driving state detecting means. K effect] Therefore, according to the present invention, it becomes possible to quickly restore the height of the vehicle body to the standard height by the automatic restoring means, and it becomes possible to return the heights of the stop lamps and tail lamps to their correct positions. At the same time, it becomes possible to prevent the angle of the optical axis of the headlamp from deviating from the correct angle.

【Example】

The present invention will be explained below with reference to an illustrated embodiment. FIG. 1 is a block diagram showing a truck bed height adjustment device according to an embodiment of the present invention, in which a front axle 11
is suspended from a frame 13 via leaf springs 12. A shock absorber 14 is interposed between the front shaft 11 and the frame 13. On the other hand, the rear and front shafts 15 are suspended from the frame 13 by leaf springs 16, and the rear ends of the leaf springs 16 are bent downward, and are supported by air springs 17. ing. A shock absorber 18 is also installed between the leaf spring 16 and the frame 13. Similarly, the rear axis 19
is suspended on the frame 13 by a leaf spring 20 and an air spring 21, and a shock absorber 2 is provided between the leaf spring 20 and the frame 13.
2 is interposed. The air springs 17.21 provided corresponding to the rear-front shaft 15 and the rear-rear shaft 19 are communicated with each other through a communication pipe 23, and these pair of air springs 17.21 are connected through a magnetic valve 24. and is connected to the surge tank 25. Note that the left and right air springs 17, 21 are independent from each other, and each is provided with a separate surge tank 25. The left and right air springs 17 and 21 are connected to an automatic air supply valve 27 and an automatic exhaust valve 28 via supply and exhaust pipes 26, respectively. Furthermore, this truck is equipped with a compressor 29. The compressor 29 is connected to a wet tank 30, and the wet tank 30 is connected to a protection valve 3.
It is connected to the reservoir tank 32 via 1. And the reservoir tank 32 is yet another reservoir tank 33
It is also connected to the automatic air supply valve 27 via the check valve 34. Generally, this check valve 34 is connected to a pair of air springs 17, 21 via a manually operated air supply valve 35. A manual exhaust valve 36 is connected to the manual air supply valve 35 . The automatic air supply valve 27, the automatic exhaust valve 28,
The actuators 37 and 38 provided on the shock absorbers 18 and 22, respectively, and the cab suspension shock absorber 39 are controlled by a microcomputer 40 constituting an electronic control device. A control panel 41 is connected to the input side of this microcomputer 40. This panel 41 is attached to the rear end of the gate on the right side of the loading platform. The panel 41 is provided with an up button 42, a down button 43, a restoring button 44, and an emergency stop button 45, respectively. Further, this panel 41 is provided with a display lamp 46, which blinks in response to an output signal from the microcomputer 40. Additionally, there is a cab suspension selector switch 48 on the instrument of the cab of this truck.
, an air suspension changeover switch 49 are provided, and these switches 48 and 49 are also connected to the input side of the microcomputer 40. Further, the transmission 50 of this truck is provided with a gear position detection sensor 51 and a vehicle speed detection sensor 52, respectively, and the outputs of these sensors 51 and 52 are also input to the microcomputer 4o. Furthermore, a bottoming detection sensor 5 is provided between the front axle 11 and the frame 13 to detect bottoming from the distance between the two.
3 is provided, and also a microcomputer 40
connected to the input side of the On the other hand, the air supply and exhaust pipes 26 of the air springs 17.21 constituting the rear suspension device are provided with live load detection sensors 54.55 that detect the live load from the pressure of these air springs 17.21. There is. These sensors 54 and 55 perform detection operations using different pressures, and are both connected to the input side of the microcomputer 40. Further, a vehicle height detection sensor 56 is provided between the rear axle 19 and the frame 13 to detect the vehicle height from the distance between the two, and is similarly connected to the input side of the microcomputer 40. A warning lamp 57 and a warning buzzer 58 are connected to the output side of the microcomputer 40, respectively. These lamps 57 and buzzers 58
Both are attached to the instrument panel of cab 47. Next, the operation of the truck bed height adjusting device having the above configuration will be explained. The operation of setting the loading platform to the standard height is performed by the microcomputer 40 based on the flowchart shown in FIG. That is, the microcomputer 40 controls the vehicle height detection sensor 5.
In addition to reading the detection output of No. 6, a standard value preset in the microcomputer 40 is also read, and the actual vehicle height is compared with the standard value. If the actual vehicle height is higher than the standard value, the microcomputer 4
0 causes the automatic exhaust valve 28 to open. The air within the air spring 17.21 is then exhausted through the exhaust valve 28, thereby lowering the height of the cargo platform. On the other hand, if the actual vehicle height is lower than the standard value,
The automatic air supply valve 27 is opened and the compressed air stored in the reservoir tank 32.33 is supplied to the air spring 17.21 through the air supply valve 27 to raise the cargo platform. In addition, if the actual vehicle height and the standard value match, the air intake valve 27
, and exhaust valve 28 are both held closed. In this way, it is possible to always hold the loading platform in a predetermined position. Note that the standard value is stored in the microcomputer 40 as a value with a predetermined width. Furthermore, in this truck, the spring constant and damping force of the suspension device are changed depending on the amount of load on the platform. The load on the loading platform is detected in stages by load detection sensors 54 and 55 consisting of pressure sensors.
The microcomputer 40 reads the detection output of 55. The magnetic valve 24 is then opened and closed depending on the loading amount. When the load is small, the magnetic valve 24 is opened and the surge tank 25 and the air springs 17.2.1 are communicated with each other to lower the spring constant of the suspension device. At the same time, the control signal from the microcomputer 40 causes the actuators 37, 38 to increase the aperture diameter of the shock absorber 18, 22 to reduce its damping force. On the other hand, if a large load is detected by the sensor 54.55, the magnetic valve 24 is closed to increase the spring constant of the air spring 17.21, and the actuator 37.38 is activated to reduce the shock absorber 18.22. This is done to increase the damping force and maintain the suspension system in an optimal condition depending on the load. Furthermore, in this truck, it is possible to set the loading platform at a desired height, for example, for loading and unloading cargo to and from the platform. This operation is the first
This is achieved by pressing the up button 42 or down button 43 of the control panel 41 shown in the figure, and the automatic air supply valve 27 or the automatic exhaust valve 28 is activated in response to the operation of these buttons 42 and 43. is opened, allowing air to be supplied to or evacuated from the air springs 17.21, thereby making it possible to align the truck bed with the platform. . Therefore, there is no difference in level between the platform and the platform, making it possible to load and unload cargo easily. When the loading and unloading work described above is completed, the truck bed is restored to its standard height. This operation is performed based on the flowchart shown in FIG. In other words, the restore button 44 of the control panel 41
When you press , the restoration switch turns ON, which causes the microcomputer 40 to detect the vehicle height detection sensor 56.
The system reads the output of , determines whether the actual vehicle height is within the standard range, and performs an operation to restore the vehicle height if it deviates from the standard range. This operation is performed based on instructions from the microcomputer 40.
or by opening the exhaust valve 28, by supplying compressed air to the air springs 17.21 or by discharging the compressed air in these air springs 17.21, returning the loading platform to its standard height. Do it like this. During this operation, the display lamp 46 is turned on. During this operation, the microcomputer 40 also reads the output of the vehicle height detection sensor 56 at regular intervals, and determines whether the value of this output is out of the standard range. continues the restoration operation. Also, the microcomputer 40
When the actual vehicle height falls within the standard range, the restoring operation is completed and the display lamp 46 is turned off. Therefore, the end of the restoration can be known from the lamp 46 turning off. Further, in this truck, if the vehicle starts traveling without performing the above-mentioned restoring operation, the restoring action is automatically performed based on the flowchart shown in FIG. This operation is performed by the microcomputer 4.
0 reads the detection output of the vehicle speed detection sensor 52, and the vehicle speed is 2.
If the speed is 0kTIl/h or more, transmission 5
The output of the gear position detection sensor 51 of 0 is read. If it is determined from this output that the transmission 50 is in second speed or higher, the output of the vehicle height detection sensor 56 is read to determine whether the actual vehicle height is out of the standard range. If it deviates from the standard range, an automatic restoration operation is performed. This operation opens the air supply valve 27 or the exhaust valve 28 until the microcomputer 40 reaches the standard height, and the air spring 17.
This is achieved by adjusting the amount of air in 21. Therefore, even if the truck starts traveling without remembering to restore the loading platform, the loading platform will be promptly restored to its standard height. Therefore, the stop lamps and tail lamps can be returned to their standard heights, and the angle of the optical axis of the headlamp can be set to the correct angle. Further, this automatic restoring operation is performed only when the speed is 20 km/h or higher and the transmission 50 is in the second gear or higher, resulting in excellent safety.

Effects of the Invention As described above, the present invention includes an automatic restoring means for restoring the vehicle height to the standard height, and the automatic restoring means restores the vehicle height in response to the operation of the manual operation means or the detection of the driving state detection means. This is to restore it to the standard height. Therefore, according to the present invention, it is possible to restore the vehicle height to the standard height by manual operation or automatically and quickly after the start of driving, and even when the vehicle height has significantly deviated from the standard height. It is possible to prevent the vehicle from running.

[Brief explanation of the drawing]

Fig. 1 is a book diagram showing a truck bed height adjustment device according to an embodiment of the present invention, Fig. 2 is a flowchart showing normal cargo bed height adjustment, and Fig. 3 is an operation of the restore button. FIG. 4 is a flowchart showing the automatic restoration operation. In addition, in the symbols used in the drawings, 17.2 Air spring 27...Automatic air supply valve 28...Automatic exhaust valve 40...Microcomputer 41...Control panel 44...Restored Button 51...Gear position detection sensor 52...Vehicle speed detection sensor 56...Vehicle height detection sensor.

Claims (1)

[Claims] In a vehicle in which at least a portion of the suspension spring is an air spring, and the height is adjusted by controlling the supply and discharge of air to the air spring by an electronic control device, the vehicle height may be adjusted to the standard height. Vehicle height adjustment characterized in that an automatic restoring means for restoring the height is provided, and the automatic restoring means restores the vehicle height to the standard height upon operation of the manual operation means or detection by the driving state detection means. Device.