JPH03178819A - Car height adjustment device - Google Patents

Abstract

PURPOSE:To simplify a jack-up work by applying the constitution wherein it is judged that a vehicle is in a jack-up state when height is not reduced, even if a control valve for height reduction is open at the time of a vehicle stop, the height is saved and height adjustment is interrupted, and the height adjustment re-starts when the height begins to be reduced. CONSTITUTION:A control part 48 reads detected height from each of height sensors 50-1 to 50-4, and a detected vehicle speed from a vehicle speed sensor, and judges whether a vehicle is in a stop condition on the basis of the detected vehicle speed. Also, when height does not come down, regardless of height reduction control valves 46-1 top 46-4 open in one of suspension devices 4-1 to 4-4, the control part 48 judges that a vehicle is in a jack-up state, interrupts height adjustment and saves the height at the level. When the height begins to drop to or below the saved level, a jack-up process is judged to be complete and the height adjustment re-starts. According to the aforesaid construction, a jack-up work becomes easy.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention relates to a vehicle height adjustment device, and in particular to a vehicle height adjustment device that prevents the vehicle height from falling when the vehicle is jacked up without requiring an operation to stop the operation of the vehicle height adjustment device. The present invention relates to a vehicle height adjustment device.

[Conventional technology]

Some vehicles are equipped with a vehicle height adjustment device that adjusts the vehicle height in a predetermined manner depending on driving conditions and the like. The vehicle height adjustment device is configured as shown in FIG. 4, for example. In the figure, 202 is a vehicle height adjustment device. Vehicle height adjustment device 20
2 is provided with respective suspension devices 204, . . . that suspend each wheel (not shown) of the vehicle using fluid pressure. In addition,
each suspension device 204 that suspends each wheel using fluid pressure;
... have the same configuration, so one suspension device 204
will be explained using an example.

A suspension system 204 that suspends each wheel using fluid pressure includes a bottomed cylindrical outer cylinder 206 attached to the wheel side, and this outer cylinder 20.
6 and is supported by the outer cylinder 206 with one end open to the bottom 208 side of the outer cylinder 206 and the other end closed to the mouth 210 side by a support part 212. 214, a piston 218 which is disposed to be slidable in the axial direction within the inner cylinder 214 and has a communication passage 216 formed therethrough in the axial direction; one end side communicates with the piston 218 and the other end side. 11; 1. A hydraulic supply passage 22 which is a fluid pressure supply/discharge passage installed inside the inner cylinder 214 so as to be slidably passed through the supporting part 212 and installed on the vehicle body side (not shown).
0, the outer cylinder 206 and the inner cylinder 2
14 between the bottom 208 of the outer cylinder 206 and
It has a metal bellows 226 disposed between the outer cylinder 206 and the inner cylinder 214 on the side.

This suspension device 204 includes the outer cylinder 206 and the connecting portion 224.
- A first chamber 228 is provided which is partitioned by bellows 226 and filled with a fluid such as nitrogen gas, and which is partitioned by the inner cylinder 214, piston 218, communication portion 224, and bellows 226 and filled with fluid pressure such as oil pressure. A second chamber 230 is provided which is supplied and discharged by the hydraulic pressure supply and discharge passage 220 of the rod 222, and is partitioned by the support portion 212, the inner cylinder 214, the piston 218, and the rod 222, and the fluid pressure of the second chamber 230 is A third chamber 232 is provided to which a barrel, for example, hydraulic pressure, is supplied and discharged through the communication passage 216 of the piston 218.

When the loft 222 moves in and out of the inner cylinder 214, the suspension device 204 moves to a second position corresponding to the volume of the rod 222 that moves out and out.
The volume of the chamber 230 is expanded or contracted, the bellows 226 is expanded or contracted, and the volume of the first chamber 228 is expanded or contracted. This allows the first
The gas pressure in the chamber 228 and the oil pressure in the second chamber 230 change in level, increasing or decreasing the load acting in the direction in which the rod 222 protrudes.

The suspension system 204 that suspends the wheels using fluid pressure in this way
The hydraulic pressure supply/discharge path 220 of the rod 222 is connected to the hydraulic pressure supply path 23
4 to the hydraulic pump 236, and a hydraulic discharge path 238 to the hydraulic pump 236 and the oil tank 24.
Contacting 0.

The hydraulic pressure supply path 234 has one end communicating with the hydraulic pump 236 and the other end communicating with the hydraulic supply/discharge path 220, and the hydraulic pressure of the hydraulic pump 236 is sequentially supplied to the accumulator 242 and the suspension device 204 from the hydraulic pump 236 side. A lifting control valve 244 is provided to raise the vehicle height. In addition, one end side is connected to the hydraulic supply/discharge passage 220 and the hydraulic pump 23
6 and a hydraulic discharge path 2 whose other end communicates with the yuzu tank 240.
38 is provided with a lowering control valve 246 that discharges hydraulic pressure from the suspension system 204 to lower the vehicle height.

The hydraulic pump 236, the ascending control valve 244, and the descending control valve 246 are connected to the output side of a control section 24B, which is a control means. On the input side of this control section 248,
A vehicle height sensor 250 provided on the suspension system 204 is connected. Note that the lifting control valve 244, the lowering control valve 246, and the vehicle height sensor 250 are provided for each suspension device (not shown), respectively.

Accordingly, the vehicle height adjustment device 202 causes the control unit 248 to supply and discharge hydraulic pressure to and from each suspension device 204, which suspends each wheel of the vehicle using fluid pressure, to raise and lower the vehicle height. The ascending control valves 244, . . . and the descending control valves 246, .
, . . . The vehicle height is adjusted to a predetermined value by controlling the opening and closing of each vehicle height sensor 250, .

That is, as shown in FIG. 5, when the control unit 248 starts controlling the vehicle height adjusting device 202 (300>),
It is determined whether the vehicle height≠set value (301). If the vehicle height is not the set value and is No, reset the timer (302)
L, return to judgment (301).

If the vehicle height≠set value is YES, the timer counts (303) L, and it is determined whether the timer>T (304). If the timer is not T and the answer is No, the process returns to judgment (301).

If YES at timer>T, it is determined whether the vehicle height is at the set value (305). If the vehicle height is not set at the set value <No, the hydraulic pump 236 is turned off and stopped, the ascending control valve 244 is closed, and the descending control valve 246 is controlled to close.
is controlled to open, and the vehicle height is lowered (306). On the other hand, if the vehicle height setting value is YES, the hydraulic pump 236 is turned on and driven, the raising control valve 244 is controlled to open, and the lowering control valve 246 is controlled to be closed, thereby raising the vehicle height (307 ).

Next, it is determined whether the vehicle height is equal to the set value (308).

If the vehicle height is not the set value and the answer is No, the process returns to judgment (305). If vehicle height = set value and YES, the hydraulic pump 236 is turned off and stopped, and the lift control valve 244 is turned off.
309)
, returns to judgment (301).

As such a vehicle height adjustment device, Japanese Patent Application Laid-Open No. 64-604
It is disclosed in Publication No. 10. The technology disclosed in this publication detects a low vehicle height when one of the vehicle height sensors located on one diagonal of each of the front, rear, left, and right suspension systems detects a high vehicle height and the other vehicle height detects a low vehicle height. When it is determined that the wheel of the suspension system is off the wheel and the vehicle height switching switch is operated in this state, fluid pressure is supplied to each suspension system located on the other diagonal of the front, rear, left and right suspension systems, and the vehicle height is adjusted. By increasing the height, escape was facilitated by the driving force of two or three wheels.

(Problems to be Solved by the Invention) By the way, in the conventional vehicle height adjustment device as described above, when the vehicle height is being adjusted and the vehicle height is being adjusted and the vehicle height is being adjusted, if the vehicle height is being adjusted and the vehicle height is being adjusted and the vehicle height is being adjusted, the vehicle height is increased. The lowering solenoid valve of the suspension system to which the wheel is attached is controlled to open, and hydraulic pressure is discharged from the suspension system.

However, even if the hydraulic pressure is discharged from the suspension system, the vehicle height does not change due to jacking up, so the opening control of the lowering solenoid valve continues, and the hydraulic pressure is completely discharged from the suspension system. In this state, when an attempt was made to remove the jack after jacking up, the problem occurred that the jack could not be removed because the vehicle height had fallen.

For this reason, conventionally, the operation of the vehicle height adjustment device had to be stopped, making the jacking-up work complicated.

[Purpose of the invention]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to prevent the vehicle height from falling when the jack is jacked up without requiring an operation to stop the operation of the vehicle height adjustment device, and to solve the inconvenience that the jack cannot be removed when the jack is finished. An object of the present invention is to realize a vehicle height adjustment device that can facilitate vehicle height adjustment work.

[Means for solving problems]

In order to achieve this object, the present invention supplies and discharges fluid pressure from a fluid pressure generation mechanism to each suspension system that suspends each wheel of a vehicle using fluid pressure, thereby raising and lowering the vehicle height. The vehicle height adjustment device adjusts the vehicle height to a predetermined value by controlling the opening and closing of a control valve and a lowering control valve in accordance with the vehicle height detected by each vehicle height sensor provided in each of the suspension systems. When the vehicle height detected by the vehicle height sensor provided on this one suspension system is not lowered even though the lowering control valve of any one of the suspension systems is controlled to be open when the vehicle is stopped. determines that the jack is in the jack-up state, stores the vehicle height detected by the vehicle height sensor installed in the first suspension at the time of determining the jack-up state, and performs control to interrupt the vehicle height adjustment; If the vehicle height detected by the vehicle height sensor falls below the vehicle height at the time of the stored jack amplifier state determination, the vehicle is characterized by being provided with a control means that determines that the jack up is completed and controls the vehicle height adjustment to be resumed. do.

[Effect]

According to the configuration of the present invention, even though the lowering control valve of any one of the suspension systems is controlled to be opened by the control means when the vehicle is stopped, the If the vehicle height detected by the height sensor is not lowered, it is determined that the vehicle is in a jack-up state, and the vehicle height detected by the vehicle height sensor installed in the first suspension system at the time of judgment of this jack-up state is memorized. Control is performed to interrupt vehicle height adjustment. If the vehicle height detected by the vehicle height sensor provided in the first suspension device falls below the vehicle height at the time of the memorized jack-up state judgment, it is determined that the jack-up is completed and the vehicle height adjustment is restarted (controllable). As a result, it is possible to prevent insects from lowering the vehicle height when the vehicle is jacked up without requiring an operation to stop the operation of the vehicle height adjustment device.4. [Example] Next, an example of the present invention is shown in the figure. I will explain the details based on this.

1 to 3 show embodiments of this invention. In FIG. 1, reference numeral 2 denotes a vehicle height adjustment device, and the vehicle height adjustment device 2 includes suspension devices 4-1 to 4-4 that suspend each wheel (not shown) of the vehicle using fluid pressure. That is, a suspension device 4-I for the right front wheel, a suspension device 4-2 for the left front wheel, a suspension device 4-3 for the right rear wheel, and a suspension device 4-4 for the left rear wheel are provided.

Each suspension device 4 suspends each of these wheels using fluid pressure.
-1 to 4-4 have the same configuration, so right t'ti7
The wheel suspension system 4-1 will be explained as an example.

As shown in FIG. 3, the suspension system 4-1 includes a bottomed cylindrical outer cylinder 6-1ε mounted on the wheel side, and is arranged concentrically within this outer cylinder 6-1. -1 with one end open on the bottom 8-1 side and the other end side open on the mouth 10-1 side of the support part 12-1.
1 and supported by the outer cylinder 6-1.
A piston 18-1 is disposed in the inner cylinder 14-i so as to be slidable in the axial direction, and has a communication passage 16-1 formed therethrough in the axial direction, and a piston 18-1 is provided on one end side of the piston 18-L. At the same time, the other end of the support part 12-1 is slidably penetrated, and a hydraulic pressure supply passage serving as a fluid pressure supply/discharge passage is installed inside the inner cylinder 14-l and is installed on the vehicle body side (not shown). Drainage channel 2
The outer cylinder 6-1 fits into the connecting part 24-1 between the outer cylinder 6-1 and the inner cylinder 14-1 and the outer cylinder 6-1.
It has a metal bellows 26-1 arranged between the outer cylinder 6-1 and the inner cylinder 14-1 on the bottom 81 side.

This suspension device 4-1 includes the outer cylinder 6-1 and the connecting portion 24-
A first chamber 28-■ is provided which is partitioned by the tobellows 26-l and filled with a fluid such as nitrogen gas. At the same time, fluid pressure, for example, oil pressure, is supplied to the hydraulic supply and discharge passage 20 of the rod 22-1.
-i is provided with a second chamber 30-1 which is supplied and discharged by
2-1 and the second chamber 30-
A third chamber 32-1 is provided in which a fluid pressure, for example, hydraulic pressure, is supplied and discharged through a communication passage IG-1 of a screw 18-1.

In this suspension device 4-1, the rod 22-1 is connected to the inner cylinder 14-i.
When the bellows 2G-■ is retracted, the volume of the second chamber 30-1 is reduced by the volume of the retracted rod 22-1.
is expanded, and the volume of the first chamber 281 is reduced. This increases the gas pressure in the first chamber 28-1 and the oil pressure in the second chamber 30-1, increasing the load acting in the protruding direction of the rod 22-1. On the other hand, when the rod 22-1 is protruded from inside the inner cylinder 14-1, the volume of the second chamber 30-1 is expanded by the volume of the protruded rod 22-■, and the bellows 26-1 is expanded.
-1 is reduced and the volume of the first chamber 228 is expanded. This reduces the gas pressure in the first chamber 28-1 and the second chamber 30-1.
The hydraulic pressure of the rod 22-1 decreases, reducing the load acting in the direction in which the rod 22-1 protrudes.

As shown in FIG. 1, the hydraulic supply and discharge passages 20-1 to 20-4 of the rods 22-1 to 22-4 of the suspension systems 4-1 to 4-2 that suspend the wheels using fluid pressure are connected to the hydraulic supply passage 34. It is connected to a hydraulic pump 36, which is a fluid pressure source, and is also connected to the hydraulic pump 36 and an oil tank 40 through a hydraulic discharge path 38. The hydraulic supply path 34, which has one end communicating with the hydraulic pump 36 and the other end communicating with the hydraulic supply/discharge paths 22-1 to 22-4, includes an accumulator 42 and the suspension device 4- in order from the hydraulic pump 36 side. Lifting control valve 44-1 that supplies hydraulic pressure from the hydraulic pump 36 to 1 to 4-2 to raise the vehicle height.
-44-4 are provided. In addition, the hydraulic supply/discharge path 20
-1 to 20-4 at one end and the other end to the hydraulic pump 36 and oil tank 40, a hydraulic discharge path 38 is provided for discharging hydraulic pressure from the suspension systems 4-1 to 4-4 to drive the vehicle. Lowering control valves 46-1 to 46-4 are provided to lower the height.

The hydraulic pump 36 and the rising control valves 44-1 to 4
4-4 and lowering control valves 46-1 to 464 are connected to the output side of a control section 48, which is a control means. An input end of the control section 48 is connected to vehicle height sensors 50-1 to 50-4 provided in the suspension systems 4-1 to 4-4.

Thereby, the vehicle height adjustment device 2 is controlled by the control unit 48 to
Each suspension device 4 suspends each wheel of the vehicle using fluid pressure.
-1 to 4-4 to supply and discharge hydraulic pressure to raise and lower the vehicle height. Suspension device 4-
The vehicle height is adjusted to a predetermined value by controlling opening and closing according to the vehicle height detected by each of the vehicle height sensors 50-1 to 50-4 provided at the vehicle height sensors 1 to 4-4.

In such a vehicle height adjustment device 2, the control section 48
indicates that the vehicle speed detected by the vehicle speed sensor (not shown) is Okm/
When the vehicle is stopped, each of the suspension systems 4-1 to 4-
4, even though the lowering control valve 46-1 of the right front wheel suspension 4-1 is controlled to open, this one suspension, the right front wheel suspension 4. If the vehicle height detected by the vehicle height sensor 50-1 provided in the vehicle height sensor 50-1 is not lowered, it is determined that the jack is up and the suspension device for the right front wheel, which is the suspension device 4-, is determined to be in a jack-up state. Vehicle height sensor 50 provided in 1
The vehicle height detected by -1 is stored, and the hydraulic pump 36 is turned off and stopped to interrupt the vehicle height adjustment, and each of the ascending control valves 44-1 to 44-4 and each of the descending control valves 4
6-1 to 46-4 are all closed and controlled. If the vehicle height detected by the vehicle height sensor 50-1 provided in the suspension system 4-1 for the right front wheel, which is the first suspension system, falls below the vehicle height at the time of the stored jack-up state judgment, the jack-up When it is determined that the vehicle height adjustment has been completed, the hydraulic pump 36 is turned on to control the drive and each raising control valve 44 is activated to restart the vehicle height adjustment.
-1 to 44-4 and each descending control valve 46-1 to 46-4
The configuration controls opening and closing of all of the above.

Next, the operation will be explained according to FIG.

The control unit 48 of the vehicle height adjustment device 2 starts the control (10
0), it is then determined whether the vehicle speed is 0 (101).

Vehicle speed = 0 (if NO, end (110)). If vehicle speed = O and YES, right front wheel suspension system 4-
It is determined whether the lowering control valve 46-1 of No. 1 is controlled to be opened (102). If the lowering control valve 46-1 is controlled to open and the answer is YES, it is determined whether the change in vehicle height of the right front wheel is <0 (103). If vehicle height change <0 and YES,
It is determined whether the lowering control valve 46-2 of the left front wheel suspension system 4-2 is controlled to open (104).

On the other hand, in the judgment (102), the suspension system 4 for the right front wheel
-1 descending control valve 46-1 is controlled to open.
In this case, the lowering control valve 4 of the suspension system 4-2 for the left front wheel
6-2 is under open control (104).

In addition, in the judgment (102), the vehicle height change <N is not 0.
If o, the process moves to process (111).

Next, in the judgment (104), the lowering control valve 46-2 of the suspension system 4-2 for the left front wheel is controlled to open, and the result is YES.
In this case, determine whether the vehicle height change of the left front wheel is <0 (10
5) Do. If the vehicle height change is <0 and YES, it is determined whether the lowering control valve 46-3 of the suspension system 4-3 for the right rear wheel is controlled to open (106).

On the other hand, in the judgment (104), the left front wheel suspension system 4
-2 lowering control valve 46-2 is open and if chair No., lowering control valve 46-3 of suspension system 4-3 for right rear wheel
It is determined whether or not the opening is controlled (106). Also,
In the judgment (105), if the vehicle height change is not 0 but No, the process moves to process (111).

Further, in the judgment (106), the lowering control valve 46-3 of the suspension system 4-3 for the right rear wheel is controlled to open, and the result is YES.
In this case, determine whether the vehicle height change of the right rear wheel is <0 (10
7) Do. If the vehicle height change is <0 and the answer is YES, it is determined whether the lowering control valve 46-4 of the suspension system 4-4 for the left rear wheel is controlled to open (t08).

On the other hand, in the judgment (106), the right rear wheel suspension system 4
If the lowering control valve 46-3 of -3 is under 1Rj release control and NO, it is determined whether the lowering control valve 46-4 of the left rear wheel suspension 44 is under Ijii release control (108
)do. In addition, in the judgment (107), the vehicle height change is 0.
If the answer is NO, the process moves to process (111).

Then, in the judgment (108), the lowering control valve 46-4 of the suspension system 4-4 for the left rear wheel is controlled to open, and the result is YES.
In this case, determine whether the vehicle height change of the left rear wheel is 0 (1,
09) Do. If vehicle height change is YES, end (
110).

On the other hand, in the judgment (108), the left rear wheel suspension system 4
-4 lowering control valve 46-4 is controlled to open.
In this case, it becomes the end (110). Also, judgment (10
In 9), if the vehicle height change is not 0 but No, the process moves to process (111).

In this way, when the vehicle is stopped, each of the suspension systems 4-1 to 4
-4, for example, the right front wheel suspension 4, even though the lowering control valve 4G-1 of the right front wheel suspension 4-1 is open.
If the vehicle height detected by the vehicle height sensor 50-i provided at the vehicle height sensor 50-i is not lowered, it is determined that the vehicle is in a jack-up state and processing (111) is performed.

In the process (i i 1), the vehicle height of the suspension system at the time of determining the jack-up state, for example, the vehicle height detected by the vehicle height sensor 50-1 provided in the suspension system 4-1 for the right front wheel, is stored in the memory. Then, in order to interrupt the vehicle height adjustment, the hydraulic pump 36 is turned off and stopped, and each of the ascending control valves 44-1 to 44-4 and each of the descending control valves 46-1 to 46 is -4 closed control (112)
do.

Then, it is determined whether the vehicle height value>memory (113),
If the answer is No, the process (112) is continued. Vehicle height value〉If YES in memory, end (
1i 0). That is, if the vehicle height detected by the vehicle height sensor 50-1 provided on the suspension system at the time of jacking up, for example, the suspension system 4-1 for the right front wheel, falls below the vehicle height at the time when the jacking up state was determined as stored above, Hydraulic pump 36 determines that the jack-up is over and resumes vehicle height adjustment.
is turned on to control the drive, and each rising control valve 44-1 to 44-4
4-4 and the lowering control valves 46-1 to 46-4 are all controlled to open and close to reach the end (110).

Thereby, it is possible to prevent the vehicle height from decreasing when the vehicle is jacked up, without requiring an operation to stop the operation of the vehicle height adjustment device 2.

Therefore, in the vehicle height adjustment device 2, it is possible to eliminate the inconvenience that the jack cannot be removed when jacking up is completed, and the jacking up work can be facilitated.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to prevent the vehicle height from decreasing when the vehicle is jacked up without requiring an operation to stop the operation of the vehicle height adjustment device.

Therefore, in the vehicle height adjustment device, it is possible to eliminate the inconvenience that the jack cannot be removed when the jack amplifier is finished, and the jack-up work can be facilitated.

[Brief explanation of drawings]

1 to 3 show embodiments of the present invention, FIG. 1 is a schematic configuration diagram of a vehicle height adjustment device, FIG. 2 is a control flowchart,
FIG. 3 is a sectional view of the suspension system. 4 and 5 show a conventional example, FIG. 4 is a schematic configuration diagram of a vehicle height adjustment device, and FIG. 5 is a control flowchart. In the figure, 2 is a vehicle height adjustment device, 4-1-4-4 is a suspension device, 20-l to 20-4 are hydraulic supply and discharge passages, and 28-1 to 2
8-4 is the first room, 30-1 to 304 are the second room, 32-1
~32-4 is the third chamber, 34 is the hydraulic supply path, 36 is the hydraulic pump, 38 is the hydraulic discharge path, 40 is the oil tank, 44-1 to 44-4 is the control valve for rising, 46-1 to 46 −4ε:j
6 is a lowering control valve, 48 is a control section, and 50-1 to 50-4 are vehicle height sensors.

Claims (1)

[Claims] 1.Each raising control valve and each lowering control valve that raise and lower the vehicle height by supplying and discharging fluid pressure from a fluid pressure generation mechanism to each suspension device that suspends each wheel of the vehicle using fluid pressure. In the vehicle height adjustment device that adjusts the vehicle height to a predetermined value by controlling opening and closing according to the vehicle height detected by each vehicle height sensor provided in each of the suspension devices, when the vehicle is stopped, one of the suspension devices is If the vehicle height detected by the vehicle height sensor installed on this suspension system is not lowering even though the lowering control valve of the suspension system is controlled to be open, it is determined that the vehicle is jacked up and this jack is not lowered. The vehicle height detected by the vehicle height sensor provided on the first suspension device at the time of determining the up state is stored and controlled to interrupt vehicle height adjustment, and the vehicle height detected by the vehicle height sensor provided in the first suspension device is controlled A vehicle height adjusting device comprising a control means for determining that jacking is completed and restarting vehicle height adjustment when the vehicle height falls below the stored vehicle height at the time of determining the jacking state.