JPH0450017A - vehicle height adjustment device - Google Patents

Abstract

PURPOSE:To incline the vehicle body of a vehicle, especially a leisure vehicle and commercial car arbitrarily at the time of parking, by inclining the vehicle body in a desired inclining direction by a driver who receives the indication of an indicating means when it has been judged that the vehicle body is necessary to incline in a cross or diagonal direction. CONSTITUTION:Respective vehicle height adjusting valves 43A-43D provided at hydraulic oil supply passages 42A-42D to hydraulic actuators 41A-41D installed respectively on four wheels, and unload valve 46 which returns hydrau lic oil fed from an oil pump 44 to an oil tank 45 are opened and closed accord ing to the indication of a means 47 which indicates that the vehicle body should be moved vertically as a general. When it is judged by a means 53 that the vehicle body is necessary to incline according to respective outputs of a switch 51 which outputs a lever inclining signal and a means 52 which judges parking time, it is indicated to the driver 48 by a means 54. Besides, a valve 50B pro vided at a passage 49B which communicates with the supply passages 42C, 42D on opposite side is opened by a driver 56.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a vehicle height adjustment device, and particularly to a vehicle height adjustment device that adjusts the inclination angle of a vehicle body during parking.

(Prior technology) When the vehicle speed increases, the vehicle height is lowered to the 71 mark position to ensure high-speed stability, and the vehicle height is always kept constant regardless of loading conditions. The device has been put into practical use.

FIG. 10 shows an example of the hydraulic circuit of such a device (Japanese Patent Application Laid-Open No. 105711/1983).

2 is a hydraulic cylinder installed in each wheel 1 (only one is shown in the figure) on the front, rear, left and right sides of the vehicle and responds to the supplied hydraulic pressure;
Reference numeral 5 designates a switching valve for vehicle height aX provided in the oil path to the hydraulic cylinder.

When the vehicle height adjustment switch (not shown) is switched from the 71 mark position to the high position in the vehicle interior, the switching valves 3 to 5 open the hydraulic oil supply passage, and the oil pump 6 is connected to the hydraulic cylinder.
Hydraulic oil is supplied from

This supplied hydraulic pressure causes the hydraulic cylinder rod to extend and raise the vehicle height.

From this state, if you switch the switch to the normal position,
The unload valve 7 is opened and the hydraulic oil supplied to the hydraulic cylinder is returned to the oil tank 8, so that the cylinder cylinder contracts and the vehicle height returns to the normal position.

(Problem to be Solved by the Invention) When parking a vehicle, particularly a Lenoyer vehicle or a commercial vehicle, there are times when it is desired to tilt the vehicle body arbitrarily. For example, it would be convenient to work on uneven ground at a camping site if the inside of the vehicle could be leveled.

However, with the conventional device, the vehicle height can only be set to either the 7-mark position or the high position, and when the vehicle is parked on a slope, it is not possible to level the vehicle from a tilted position.

The present invention has been made in view of these conventional problems, and an object of the present invention is to provide a device that can tilt a vehicle body arbitrarily.

(Means for Solving Problem i#) The first invention, as shown in FIG. vehicle height adjustment valves 43A to 43D installed in the hydraulic oil supply passages 42A to 42D, and an unload valve that is opened in response to a control signal and returns the hydraulic oil pumped from the oil pump 44 to the oil tank 45. 46, means 47 for instructing the vehicle body to move up and down as a whole, and drivers 48 and 4 for opening and closing the unload valve 46 and the four vehicle height adjustment valves 43A to 43D in accordance with instructions from the instructing means 47.
The two supply passages for the front and rear (42 A, 42 B for the front, 42 C, 42 for the rear)
valves 50A and 50B installed in the passages 49A and 49B that communicate with each other (referred to as D), a switch 51 that outputs a signal according to the direction in which the lever is tilted, and a means for determining whether or not the vehicle is parked. 52, means 53 for determining whether or not the vehicle body should be tilted in the longitudinal direction or diagonal direction upon receiving a signal from the switch 51 when the vehicle is parked at 11L; means 54 for instructing the driver 48 to tilt the vehicle body in that direction when it is determined that the vehicle body is tilted in that direction;
Two supply passages for B or only one for 4.1 A.
A means 55 for instructing that the supply passage 42D communicates with the supply passage 42 on the opposite side according to the instruction of the instructing means 55.
Valve SOB interposed in passage 49B communicating C and 42D
A driver 56 is provided to open the opening.

The second invention, as shown in FIG. 1(B), includes hydraulic actuators 41A to 41D provided for each of the four wheels, and hydraulic oil supply passages 4.2A to 42D to these actuators 41A to 41D. Each of the vehicle height adjustment valves 43A to 4.3D installed in the
5; a means 47 for instructing the vehicle body to move up and down as a whole; and an unload valve 46 for opening and closing the unload valve 46 and the four vehicle height adjustment valves 43A to 43D according to instructions from the instructing means 47. a switch 51 that outputs a signal corresponding to the direction in which the operating lever is tilted; a means 52 for determining whether or not the vehicle is parked; A means 57 for determining whether it is desired to tilt the vehicle, and a means 58 for instructing the driver 48 to tilt the vehicle body in that direction when it is determined that the vehicle body is desired to be tilted in the left-right direction are provided.

The third invention is as shown in FIG. 1(C).
), the diagonal inclination indicating means 54, a sensor 61 for detecting the vehicle height of each wheel, a means 62 for receiving this sensor signal and calculating the average vehicle height LA at the time of parking, and this average rate ^LA means 63 for determining whether the value is higher than the reference value LN;
Hand 86 for determining whether the load valve is closed
4, and from these judgment results, the average vehicle height LA is the standard value,
, and the unload valve is closed, and the longitudinal and diagonal direction determining means 53 determines that it is desired to tilt in the longitudinal direction or diagonal direction. The 7 cutieators 41A, 41B or 41C, 41D on either side perform a raising operation to tilt the vehicle body, and if that is still insufficient, the 7 cutieators 41C, 41 on the side that did not perform the lifting operation.
D, 41A, 41B, and a means 65 for instructing to tilt the vehicle body by successively performing the lowering operation by 41A, 41B.

The fourth invention is as shown in FIG.
), a sensor 61 detects and outputs the vehicle height of each wheel, a means 62 receives this sensor signal and calculates the average vehicle height LA at the time of parking, and this average vehicle height LA is the standard. means 63 for determining whether the unload valve is closed or not; and means 64 for determining whether the unload valve is closed; is closed, and when the left-right direction determination means 57 determines that it is desired to tilt in the left-right direction, the 7 cutieators 41A, 41D or 41B, 41 on either the left or right side are closed.
Perform the raising operation by C to tilt the vehicle body, and if it is still insufficient, actuator 4 on the side that did not perform the operation.
1 B, 41 (4?:I; i41 A, means 66 for instructing to continue the lowering operation by 41D to tilt the vehicle body.

(Operation) In the first invention, when it is determined by the I111 means 53 that the vehicle body should be tilted in the longitudinal direction or in the diagonal direction, and in the second invention, the determination instruction 57 indicates that it is desired to tilt the vehicle body in the left-right direction. If it is determined that the
8.56 causes the vehicle body to tilt in that direction.

In addition, when the vehicle body is tilted in the longitudinal direction or diagonal direction in the first invention, if the communication valve 50A or 50B on the side that is not controlled is opened and the actuator pressures of the left and right wheels are made the same, the 70-ton side Or the static roll stiffness on the rear side becomes zero.

In the third invention and the fourth invention, when the average vehicle height LA is higher than the reference value and the unload valve is closed, priority is given to the raising operation when tilting the vehicle body,
If this is still not enough, the lowering operation continues.

(Example) FIG. 2 is a hydraulic circuit diagram of one embodiment.

11 is an oil tank, 12 is an oil pump, 13 +i
7 load valve, 14 check valve, 15.1
Reference numeral 6 indicates valve assemblies for front wheels (front) and rear wheels (rear). Reference numerals 17 to 20 indicate hydraulic actuators including hydraulic sills, air springs, and the like.

The front valve assembly 15 includes a 70-depider 1 that divides hydraulic oil into two supply passages 15A and 15B.
5C, each branched passage 15A.

Valve 15D for vehicle height adjustment provided at 1 and 5B.

15E, a valve 15G provided in a communication passage 15F between the two passages 15A and 15B, and an orifice 15H. The same applies to the rear valve assembly 16.

Four vehicle heights for each wheel! Maintenance valve 15
D, 15E, 16D, 16E and the two valves 15G, 16G provided in the communication passages 15F, 16F are all O.
This is an N/OFF switching valve, and switching is controlled according to a signal from the CPU 31.

The four hydraulic actuators 17 to 20 are arranged in this order: left front, right front, right rear, and left rear. As shown in Fig. 4, ■ is the left front, ■ is the right front, ■ is the right rear, and ■ is the left rear. shall be expressed.

FIG. 3 is a system diagram of the control system.

21 is a sensor that detects the vehicle height L1 to L4 of each wheel, 22 is a sensor that also detects the Schilling pressure pl-p4 of each wheel, 23 is an acceleration sensor, and 24 is a vehicle speed sensor. Note that the numbers 1 to 4 assigned to the height and pressure P correspond to ■- in Figure 4.
It corresponds to the number 〇.

Reference numeral 25 denotes four operation switches that are turned on and off by an operation lever for tilting the vehicle attitude provided inside the vehicle interior. These four operating switches are arranged around a stick-shaped lever 26, as shown in FIG.
#If you tilt it to the rear left/right or diagonally, only one of the four operation switches (front left switch 25A, front right switch 25B1, rear right switch 25C, rear left switch 25D) will be activated.
Or by turning on two switches at the same time,
You will be instructed which direction to tilt the vehicle.

These switches 24A to 24D and the sensors 21 to
The CPU 31 receiving the signal from 24 performs the operations shown in FIGS. 4 to 9 to tilt the vehicle body.

However, the tilting operation of the vehicle body is performed only when parking.
6 is tipped in any direction from the neutral position.

Note that the CPU 31 also performs conventional vehicle height control. For example, when the vehicle height adjustment switch (not shown) is in the high position, the unload valve 13 is closed and the oil pump 12 pumps hydraulic oil, and
4 vehicle height adjustment valves 15D, 15E, 16D, 16
Turn on all E, open it, and lift the car body as a whole.

(a) Determination of conditions under which the vehicle posture can be tilted Only when all of the following conditions are met, it is determined that the vehicle posture can be tilted (during parking).

a. Igni assistance b. The engine rotation speed is a constant rotation speed (a rotation speed higher than the cranking speed of the starter motor and lower than the idling speed, usually about 400 to 500 rpm).

c. III speed must be below a certain value (okw/h).

d. The parking brake is operating. 6. Determination of operation mode 1. Average vehicle height of the four wheels when switches 25A to 25D are turned on for the first time after all of the conditions a to d above are satisfied. (1/4) (L+10L2+L30L4)).If the average military height^ is higher than the set value LN,
It is determined that the Shirin Blonde is extending due to the vehicle height adjustment, so please shorten the Shirin Blonde (
(lowering motion) to tilt the vehicle body. On the other hand, LA is LN
If it is lower, the shin blond is in a contracted state, so the car body is tilted by stretching the shin blond (raising motion).

11. Based on the ON/OFF status of the four switches 25A to 25D, determine which operating mode the device is in by referring to the comparison table below.

An operation mode that tilts the car body in the direction of the comparison table, ``0-le mode'' is an operation mode that tilts the car body left and right, and 1N angle mode is an operation mode that tilts the car body diagonally (N angle), such as lowering the front right side. It is.

(c) Pitch mode j: Determine whether the vehicle body is to be tilted forward or backward. For example, it is assumed that it is determined that the vehicle body is to be tilted forward because the operating lever 26 wants to be pushed forward (the left front and right front switches are turned on at the same time).

ii. Once this is decided, turn on and off the unload valve 13 to determine whether to tilt the rear by 7 degrees or by tilting the rear.
Judging from F. To tilt the vehicle forward, (a)
There are two methods: (b) lowering the front and (b) raising the rear, but when the unload valve 13 is ON (closed), the rear is raised first.

iii. As a result of this determination, the unload valve 13 is
When the position is N, hydraulic oil is being fed under pressure by the oil pump, so the raising operation is performed by opening the left and right vehicle height adjustment valves 16D and 16E on the rear side.

At this time, open the valve 15G on the front side, which is not controlled, to make the shilling pressure on the left and right wheels on the 70-ton side the same. This is to make the static roll stiffness on the front side zero and stabilize it dynamically by communicating the left and right wheel sills.

If this operation is performed continuously within the operating range of the hydraulic cylinder, the vehicle body will gradually tilt, and when the vehicle body becomes horizontal due to this operation, the operating lever should be returned to the neutral position.

However, if the ON signal from the operation switch continues even if the shilling rod begins to extend to the upper limit,
It is presumed that the tilt angle is insufficient. Therefore, in this case, temporarily close the vehicle height adjustment valves 16D and 16E on the 1st gloss side, and at the same time turn off the unload valve.
After opening the left and right vehicle height adjustment valves 15D and 15E on the front side, open the communication valve 16G on the rear side.
By opening it, the front side is lowered.

1v. Warning of vehicle attitude tilt limit Even though the shilling stroke has reached the lower limit LLF due to the lowering movement of the front side, O from the operation switch is not pressed.
If the N signal continues, a warning sound is generated to notify the operator that the operating limit has been reached.

(2) Roll mode The second mode is basically the same as the pitch mode. However, in this mode, the communication valve 15
G, 16G cannot be opened.

(e) In diagonal mode, for example, when only the left front switch 25A is turned on by lever operation, when the vehicle body is tilted forward to the left by raising the vehicle, hydraulic oil is supplied to the right rear hydraulic cylinder, which is diagonal to the left front. do. At this time, do the same thing as in pitch mode, and connect the communication valve 1.5 G on the front side that is not operating.
open it.

Even if the shilling stroke reaches the upper limit of mint due to this upward movement, if it seems that the inclination is not enough, the downward movement is performed further.

(f) If a lifting operation is performed following a prohibition condition, make sure that the operation does not exceed the upper limit of the shilling stroke (LHF for the front shilling, LHR for the rear shilling).

On the other hand, in the case of a downward movement, the lower limit of the shilling stroke is 7) (7).
, LLR for the rear shilling) and minimum pressure limit for the shilling (P for the front shilling)
LF% Based on rear side shilling (P LR).

On the other hand, for the diagonal mode, 7
The two wheels on the zero or rear side are also restricted so that they do not operate beyond the stroke limit on the extension side or contraction side, depending on the operation.

FIGS. 6 to 9 show the control contents of (a) to (f) above as a routine that provides the CPU with the control contents. In addition, in the figure, "U/L-VJ means the unloading valve, and UFRJ and rRRJ in front of the communication valve (communication valve) mean the front side and the rear side, respectively. "■ Valve"
~ ■ ~ ■ of "■ Valve" correspond to the arrangement shown in FIG. 4.

In addition, in correspondence with FIG. 1(A) to FIG. 1(D>), S3
is the average vehicle height calculation means 62, S4 is the determination means 63, S5 and S6 are front and rear, the diagonal direction determination means 53, the left and right direction determination means 57, S22. S32. S52°S60. S72. S8
2. S92, 5102 is 7-load valve dark closing determination means 64, S7 to SIO, 523-331, S33 to S41
．． S73~S81°S83~S91, S93
~5101.5103~5111 is the inclination instruction means 65,
S7~SI0, 353~S59. S61 to S67 serve as the tilt instructing means 66.

(g) *High return When re-starting after parking, the previously tilted vehicle must return to its original height.

In the same manner as when the vehicle posture is tilted, it is determined whether to start with a raising motion or a lowering motion, based on the average vehicle height at the time of return determination.

ii, *The raising or lowering operation is performed sequentially starting from the shilling with the largest difference between the target value instructed by the high-adjustment changeover switch and the actual vehicle height detected by the vehicle height sensor.

Here, the operation of this example will be explained.

When the indoor operation lever 26 is tilted in any direction from the neutral position in a parked state, only one or two of the four operation switches 25 provided in total, one each on the front, rear, left and right sides, are turned on at the same time. In CPtJ31 receiving this signal, 4
By independently raising and lowering the two hydraulic cylinders, the vehicle is tilted in the same direction as the operating lever 26 is tilted.

Therefore, even if you can only park on a slope, such as at a camping site, you can level the interior of the vehicle by operating a lever, allowing you to carry out tasks such as loading and unloading luggage or leisure equipment from the luggage compartment or luggage room. becomes easier.

Note that when tilting in the front-rear direction or diagonal direction, the communicating pulp on the side where no control is performed is pinched, and the shilling pressures of the left and right wheels are made the same. Therefore, the static roll stiffness on the front side or the rear side becomes zero, so that the vehicle body can be tilted without becoming unstable.

In addition, when tilting the vehicle body, first perform either a raising operation or a lowering operation based on the average vehicle height LA at the time of initial operation of the control lever. If that is not enough, the sill on the opposite side is operated to further tilt in the same direction, so the maximum shilling stroke can be used to increase the angle of inclination of the vehicle body.

In particular, when the clearance between the vehicle and the road surface is small, if the lowering operation is performed first, there is a risk of interference with the road surface, but when the unload valve is ON, the raising operation takes priority. Therefore, such road surface interference can be avoided.

However, even if you use the maximum shilling stroke, it may not be possible to level the vehicle, in which case a warning will be given that the slope of the slope is steeper than the vehicle attitude slope limit. This prevents the tilting of the vehicle body from continuing to be operated.

Furthermore, since prohibition conditions are set independently for the operation of each hydraulic cylinder, the inclination of the vehicle attitude is prevented from being restricted more than necessary. For example, if you set limits on all four wheels at the same time at the upper and lower limits of the shilling stroke,
When one wheel on the front side exceeds the upper limit, a problem occurs in which each wheel on the rear side cannot be lowered.

(Effect of the invention) In the first invention, the second
In the invention, the vehicle body can be tilted in the left and right directions, so when Lenoyer vehicles and commercial vehicles are parked on rough terrain, the vehicle body can be tilted horizontally, improving work efficiency. improves.

In the invention of $3 and the fourth invention, if the average vehicle height at the time when the ON signal from the tilt switch is inputted exceeds the reference value and the Gatsu unload valve is closed, the raising operation is prioritized and the vehicle body is lowered. Since the vehicle is tilted, and if the tilt is still insufficient, the vehicle body is tilted by performing a lowering operation, which makes it possible to increase the tilt angle of the vehicle body and to avoid interference with the road surface.

[Brief explanation of the drawing]

Figures 1 (A) to 1 (D) are diagrams corresponding to claims of each invention, Figure 2 is a hydraulic circuit diagram of one embodiment, Figure 3 is a control system diagram of this embodiment, and Figure 4 is a diagram of this embodiment. FIG. 5 is a plan view showing the arrangement of the four hydraulic cylinders of this embodiment, FIG. 5 is a perspective view showing the arrangement of the operation switches of this embodiment, and FIGS. 6 to 9 are diagrams for explaining the control contents of this embodiment. Flowchart, #110
The figure is a hydraulic circuit diagram of a conventional example. 11... Oil tank, 12... Oil pump, 1
3...Ashiroad valve, 14...Check valve, 15.16...Valve assembly 15A, 15
B. 16A, 16B...supply passage, 15D, 15E, 16
D, 1.6E...Vehicle height adjustment valve, 15F, 16F
...Communication path, 15G, 16G...Valve, 17~2
0...Hydraulic actuator, 21...Vehicle height sensor,
22... Pressure sensor, 25... Operation switch (tilt switch), 31... CPU, 42A to 42D...
Supply passage, 43A to 43D...Vehicle height! p! Maintenance pulp, 44... Oil pump, 45... Oil tank, 46... Unload valve, 47... Vehicle height up/down instruction means, 48... Driver, 49A, 49B... Connection Passageway, 50A, 50B... Valve, 51... Inclination switch, 52... Parking determination means, 53... tf
fk l diagonal direction determining means, 54... front and back, diagonal inclination instructing means, 55... communication instructing means, 56... driver, 57... left and right direction determining means, 58... left and right inclination instruction Means, 61...Vehicle height sensor, 62...Average vehicle height calculation means, 63...Determination means, 64...Unload valve opening/closing determination means, 65...Inclination instruction means, 66.
...Inclination instruction means.

Claims (1)

[Scope of Claims] Hydraulic actuators provided for each of the first and fourth wheels, vehicle height adjustment valves interposed in hydraulic oil supply passages to these actuators, and hydraulic oil control valves that are opened in response to control signals. an unload valve that returns the hydraulic oil pumped from the pump to the oil tank; a means for instructing the vehicle body to move up and down as a whole; and the unload valve and the four vehicle height adjustment valves according to instructions from the instructing means. A driver for opening and closing, a valve installed in each passage communicating the two supply passages for the front and rear, a switch that outputs a signal according to the direction in which the operating lever is tilted, and a switch that outputs a signal depending on the direction in which the operating lever is tilted. means for determining whether or not the vehicle body should be tilted in the longitudinal direction or diagonal direction in response to a signal from the switch during parking; means for instructing the driver to tilt the vehicle body in that direction when it is determined that the vehicle body is tilted in that direction; and means for instructing the driver to communicate with the supply passage to the actuator operated by the driver and the supply passage on the opposite side; and a driver for opening a valve interposed in a passage communicating with the supply passage on the opposite side in accordance with an instruction from the instruction means. 2. Hydraulic actuators provided for each of the four wheels, vehicle height adjustment valves installed in the hydraulic oil supply passages to these actuators, and actuators that are opened in response to control signals and pumped from the oil pump. an unload valve that returns oil to the oil tank; a means for instructing the vehicle body to move up and down as a whole; and a driver for opening and closing the unload valve and the four vehicle height adjustment valves in accordance with instructions from the instructing means; A switch that outputs a signal according to the direction in which the operating lever is tilted, a means for determining whether the vehicle is parked, and a means for determining whether the vehicle body is to be tilted left or right in response to the signal from the switch during parking. 1. A vehicle height adjustment device comprising: means for determining, and means for instructing the driver to tilt the vehicle body in that direction when it is determined that the vehicle body is desired to be tilted in the left-right direction. 3. The longitudinal and diagonal inclination indicating means includes a sensor that detects the vehicle height of each wheel, a means that receives this sensor signal and calculates the average vehicle height when parking, and whether or not this average vehicle height is higher than a reference value. a means for determining whether the unload valve is closed; a means for determining whether the unload valve is closed; and a means for determining whether or not the unload valve is closed; If the diagonal direction determining means determines that the vehicle body should be tilted in the front-rear direction or diagonal direction, the actuator on either the front side or the rear side performs a raising operation to tilt the vehicle body, and even that is sufficient. 2. The vehicle height adjusting device according to claim 1, further comprising means for instructing the vehicle body to be tilted by performing a lowering operation by the actuator on the side that did not operate if the actuator is not operated. 4. The left/right tilt indicating means includes a sensor that detects the vehicle height of each wheel, a means that receives this sensor signal and calculates the average vehicle height when parking, and determines whether this average vehicle height is higher than a reference value. means for determining whether the unload valve is closed; and means for determining whether or not the unload valve is closed; If it is determined that the vehicle is to be tilted to the left or right, the actuator on either the left or right side is used to raise the vehicle to tilt the vehicle;
3. The vehicle height adjusting device according to claim 2, further comprising means for instructing the vehicle body to be tilted by continuing the lowering operation by the actuator on the side that has not been operated if the lowering operation is still insufficient.