JPS62199514A - Height control device - Google Patents

Abstract

PURPOSE:To improve safety where at least a part of suspension springs is composed of air springs by making height control possible when a primary switch is changed over to a mode allowing manual actuation. CONSTITUTION:The rear front wheel 15 and the rear rear wheel 19 of a truck are suspended from a frame 13 by means of leaf springs 16 and 20 and air springs 17 and 21. And respective air springs 17 and 21 are communicated with each other, and are connected with an automatic suction valve 27 and an auto matic exhaust valve 28. And height is controlled by a step of controlling respec tive valves 27 and 28 by a computer 40 based on the output from a manual actuation button 42 and the like. In this case, height control by the manual actuation button 42 is made possible when a mode selection button 43 comprising a primary switch is switched over to an 'adjust' position. And if the manual actuation button 42 is actuated when the mode selection button 43 is out of the 'adjust' position, an operation lamp turns on and off for giving a warning.

Description

[Detailed description of the invention] [Industrial application fields] The present invention relates to a vehicle height adjustment device, and in particular, at least a part of a suspension spring is composed of an air spring, and air is supplied to the air spring or air is discharged from the air spring in accordance with the operation of a manual operating means. The present invention relates to a vehicle height adjustment device that adjusts vehicle height by adjusting the vehicle height. Summary of K invention]

The present invention allows the vehicle height to be adjusted by operating the manual operating means in a state where the original switch associated with the manual operating means is switched to a manually operable mode, and furthermore, the original switch is manually operable. If the manual operation means is operated in a state where the mode has not been changed, an alarm is issued, thereby further increasing safety. K Prior Art: At least a portion of the suspension spring of a truck is constructed from an air spring, and the height of the loading platform is adjusted by supplying air to the air spring or discharging air from the air spring. becomes possible. Furthermore, the supply and discharge of this air is controlled by an electronic control device such as a microcomputer, and
By setting the height of the loading platform to an arbitrary height using a push button, it becomes possible to easily load and unload cargo by eliminating the level difference between the platform and the loading platform. [Problems to be Solved by the K Invention] When adjusting the vehicle height of the cargo platform manually as described above, a mode selection button is provided on the control panel, the mode selection button is set to the "adjustment" mode, and The height of the loading platform will be manually adjusted by operating the manual operation button. Therefore, even if you simply switch the manual operation button on the control panel to the "up" or "down" state, if the mode selection button is not switched to the "adjustment" mode, the vehicle height will not be adjusted correctly. . However, if you first switch the manual operation button to "up" or "down" and then switch the mode selection button to "adjust",
At this point, the vehicle height may unexpectedly rise or fall. The present invention has been made in view of such problems, and when the manual operation means is operated in a state where the original switch linked with the manual operation means is not switched to an operable state, It is an object of the present invention to provide a vehicle height adjustment device that notifies an operator of this fact. Means for Solving Problem K] As shown in FIG. 1, the present invention provides a suspension spring in which at least a portion of the suspension spring is constituted by an air spring, and air is supplied to the air spring when a manual operating means is operated. In the device, the vehicle height is adjusted by discharging the vehicle, and the device is provided with a main switch associated with the manual operation means and an alarm means for issuing an alarm, and the main switch is switched to a mode in which manual operation is possible. In this state, when the manual operation means is operated, the vehicle height is adjusted, and when the manual operation means is operated when the original switch is not switched to a mode in which manual operation is possible, an alarm is issued. This is what I did. [K effect] Therefore, according to the present invention, if the manual operating means is operated in a state where the original switch is not switched to an operable state, an alarm is issued.
This will alert the operator that the original switch has not been switched to an operable state.

【Example】

The present invention will be explained below with reference to an illustrated embodiment. FIG. 2 is a block diagram showing a truck bed height adjustment device according to an embodiment of the present invention, in which the 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 rear front fFIl 115 and the frame 13. Similarly, the rear axle 19 is suspended on the frame 13 by a leaf spring 20 and an air spring 21, and a shock absorber 22 is interposed between one rear wheel and the frame 13. 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. Roughly this truck is equipped with a compressor 29. The compressor 29 is connected to a wet tank 30, and the wet tank 3o 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. Furthermore, 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 in 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 a manual operation button 42 for manually adjusting the vehicle height and a mode selection button 43 for selecting a vehicle height adjustment mode. Further, this panel 41 is provided with an operating lamp 44, which blinks in response to an output signal from the microcomputer 40. Furthermore, a cab suspension changeover switch 48 and an air suspension changeover switch 49 are provided on the instrument panel of the cab of this truck, 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 40. A bottoming detection sensor 5 is provided between the front axle 11 and the frame 13 to detect bottoming from the distance between them.
3 is provided, and also a microcomputer 40
connected to the input side of the The parking brake lever 60 is also provided with a parking brake sensor 61, the output of which is input to the microcomputer 40. On the other hand, the air supply/exhaust vias 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, a warning buzzer 58, and an alarm buzzer 59 are connected to the output side of the microcomputer 40, respectively. These lamps 57 and buzzers 58 and 59 are both attached to the instrument panel of the 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 a flowchart not shown in FIG. That is, the microcomputer 40 controls the vehicle height detection sensor 5.
In addition to reading the detection output of 6, a standard value previously set 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 opened and closed depending on the loading interval. When the load is small, the magnetic valve 24 is opened and the surge tank 25 and the air spring 17.21 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 loading interval 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. Next, the operation of manually adjusting the height of the truck bed will be described. This operation is performed by operating the control panel 41. That is, as shown in FIG.
Switch the mode selection button 43 to the "adjustment J" position. In this state, switch the manual operation button 42 to the "up" position.
Or switch it to the "lower" position. This opens the air supply valve 27 or the exhaust valve 28, and compressed air is supplied to the air springs 17.21, or compressed air is discharged from these air springs 17.21 to adjust the height of the loading platform. It will be done. The operation of this adjustment is
It is stopped when the manual operation button 42 is switched to the "Hold J" state and when the vehicle height exceeds the upper or lower limit value.
The air supply valve 27 or exhaust valve 28 will be closed. In this way, the vehicle height adjustment operation is performed using the control panel 41.
This is done by first switching the mode selection button 43, which constitutes the original switch, to the "adjustment" state, and then operating the manual operation button 42. However, when this operation is reversed and the manual operation button 42 is switched to "up" or "down", the mode selection button 43 is changed to "adjust".
Since the switch has not been made, the vehicle height adjustment operation is not performed. If the vehicle is left in this state and the mode selection button 43 is later switched to "adjustment", the vehicle height adjustment operation will suddenly start at this point, potentially causing a safety problem. Therefore, as shown in FIG. 5, if such a reverse operation is performed, an alarm is issued to notify the operator of this fact. That is, microcomputer 4
0 reads the output of the mode selection button 43, which is the original switch of the control panel 41, and the manual operation button 42 switches to "up" or "down" even though the switch corresponding to this button 43 is not "adjust". If the learning operation is performed, the operation lamp 44 is blinked to perform a learning operation. This will cause control panel 4
It becomes possible to notify the operator of an incorrect operation on 1, and the operator can then "hold" the manual operation button 42.
It will be switched to. Therefore, when the mode selection button 43 is switched to "adjustment J", the vehicle height will not change suddenly. Note that here, the operation lamp 44 is used as a warning means, but the warning lamp 57, warning buzzer 58, The alarm may be issued by other alarm means such as a buzzer 59.

【Effect of the invention】

As described above, the present invention is configured to issue an alarm when the manual operating means is operated in a state where the original switch is not switched to a mode in which manual operation is possible. Therefore, if the manual operating means is operated without switching the original switch to a predetermined position, this malfunction will be notified by an alarm, and the operation by the manual operating means will be returned to the correct state. Therefore, when the main switch is switched to an operable state, the vehicle height is prevented from being suddenly adjusted, thereby improving safety.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing the gist of the present invention, Fig. 2 is a block diagram showing a vehicle height adjustment device for a truck bed according to an embodiment of the present invention, and Fig. 3 shows the operation of vehicle height adjustment. FIG. 4 is a flowchart showing the operation of manually adjusting the height of the loading platform, and FIG. 5 is a flowchart showing the alarm operation in case of malfunction. In addition, in the symbols used in the drawings, 17.21...Air spring 27...Automatic air supply valve 28...Automatic exhaust valve 41...Control panel 42...Manual operation button 43...Mode selection Button 44... is an operating lamp.

Claims (1)

[Claims] At least a part of the suspension spring is composed of an air spring, and the vehicle height is adjusted by supplying or discharging air to or from the air spring in accordance with the operation of a manual operating means, wherein the manual operating means and an alarm means for issuing an alarm, and when the manual operating means is operated in a state in which the original switch is switched to a mode in which manual operation is possible, the vehicle height is adjusted; A vehicle height adjustment device characterized in that an alarm is issued when the manual operation means is operated in a state where the original switch is not switched to a mode in which manual operation is possible.