JPS6137509A - Electronically controlled suspension device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an electronically controlled suspension device having a vehicle height adjustment function.

[Technical background of the invention and its problems]

In conventional electronically controlled suspension systems equipped with a vehicle height adjustment function, in order to minimize the frequency of unnecessary vehicle height adjustments (vehicle height adjustment for nose dive or trailing) when the car is stopped, When the vehicle speed changes from 3 km/h or more to 3/h or less, vehicle height adjustment is prohibited for 6 seconds, and when the 6 seconds have passed, the current vehicle height data and the previous vehicle height data are the same. There is known a device in which a stop logic is established and further vehicle height adjustment is prohibited if the vehicle height is within a preset range near the target vehicle height.

However, due to the setting of the vehicle height sensor in this device, [
The vehicle speed decreases below 3 and the stop logic is established, and after K
There was a problem in that when the vehicle was moving at 3 kB/ or less and the vehicle height changed due to deceleration by brake operation or acceleration by accelerator operation, the stop logic was canceled and unnecessary vehicle height adjustment was started.

[Purpose of the invention]

The present invention has been made in view of the above points, and its purpose is to prevent vehicle height adjustment until the door is opened even if the vehicle body moves at 3 kV'h or less after the stop logic is established. We are busy providing an electronically controlled suspension system that prevents the necessary vehicle height vI4 adjustment from starting.

[Summary of the invention]

A hydraulic suspension unit interposed between a wheel side member and a vehicle body side member of a vehicle and having a fluid chamber for adjusting vehicle height;
Todo, in an electronically controlled suspension system equipped with a vehicle height adjustment means that adjusts the vehicle height by controlling the supply and discharge of air to the single-crystal adjustment fluid chamber of the above-mentioned hydraulic suspension unit, the vehicle height adjustment is stopped. When the vehicle speed decreases from a state where the vehicle is in a state where the vehicle is in a state where the vehicle is in a closed position, vehicle height adjustment is prohibited until the door is opened to prevent unnecessary vehicle height adjustment.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 2 is a schematic diagram of a car equipped with this device.

As shown in FIG. 2, between the left and right ends of the front wheel FA side axle and the vehicle body B side member, front air suspension insulators FS (FSJ) are installed.

FSj) is interposed, and between the left and right ends of the rear wheel BA side axle and the vehicle body B side member, there is a
R5 (881, R
8j) is interposed.

Korera's air suspension (any) FSJ.

FSJ, R8J, and R8J are each t! Since they have similar structures, the air suspension unit will be described below using the reference numeral 8, as shown in Fig. 1, unless the front suspension unit and the rear suspension unit are specifically explained. In other words, these air suspension units S are illustrated and explained with only the parts necessary for vehicle height control.
A strut a damping force switching type shock absorber 1 is incorporated, and this shock absorber 1 is installed on the front wheel F.
A @ or a cylinder attached to the rear wheel BA side, and a piston slidably inserted into this cylinder, and the cylinder moves up and down with respect to the piston rod 2 in accordance with the up and down movement of the wheel. Sh.

It is a trap that exhibits a damping function according to the position of the shock absorber 1 to effectively absorb shock and shock.

Incidentally, a main air spring chamber 3 which also serves as a fluid chamber for adjusting vehicle height is disposed coaxially with the piston rod 2 in the upper part of the shock absorber 1. Since the main air splash chamber 3 is formed with air, the piston rod 2 can be moved up and down by supplying and discharging air to the main air splash chamber 3.

Further, a sub air spring chamber 5 is disposed coaxially with the piston rod 2 directly above the main air spring chamber 3 .

Further, the outer wall of the shock absorber 1 is provided with an upwardly facing spring receiver 6a, and the outer wall of the auxiliary air spring chamber 5 is provided with a downwardly facing spring receiver 6b. 6&.

A coil spring 7 is loaded between 6b.

Further, these air spring chambers 3.5 are connected to each other via a communication passage 9 bored in a control rod 8 which is rotatably inserted into the piston rod 2. An on-off valve 10 constituting a spring constant switching mechanism is interposed in the passage 9.

This on-off valve 10 includes a first valve portion 10m that cuts off communication between the auxiliary air spring chamber 5 and the communication passage 9, and a main air spring block 3.
The second valve part 10b is configured to cut off communication between the valve and the communication passage 9.

Therefore, when the on-off valve 10 is in the open state, the main air spring chamber 3 and the auxiliary air spring chamber-6 can be brought into communication to reduce the spring constant (soft K), and the on-off valve 10 is in the closed mode. In this case, the main air spring chamber 3 and the auxiliary air spring chamber 5 are placed in a disconnected state, and the spring constant can be increased () or -d.

That is, by rotating the control rod 8, the on-off valve 10 can be opened and closed, and by this opening and closing, the spring chamber capacity can be changed.

By changing this spring capacity, the spring constant of the suspension can be changed.

Furthermore, a control valve 8 & that can change the orifice area of the piston 1 a of the shock apnoparator 1 is provided at the lower end of the control rod 8 . This control valve 8
a is controlled by the control rod 81C to increase the orifice area of the piston 1a to reduce the damping force when the on-off valve 10 is in the open mode, and to reduce the orifice area of the piston 11 when the on-off valve 10 is in the closed mode. It is configured to increase the damping force.

Thus, the vehicle height adjustment of the automobile is carried out by the configuration shown in Fig. 1g1. That is, as shown in FIG. 1, compressed air for adjusting the vehicle height is supplied from a compressor 11 as a compressed air generating device to a dryer 12, a joint 13, a rear solenoid pulp 14, a front solenoid pulp 15, and each of these. A connection port 17 that communicates with the connecting pipe 16 and the communication passage 9 in the control rod, which is partially shaped like a hub.
It is designed to be supplied to each suspension 22, 2 and S via.

The compressor 11 compresses the atmospheric air sent from the air cleaner 18 and supplies it to the dryer 12. The compressed air dried by silica gel etc. in the dryer 12 is shown by each solid line arrow in FIG. 1 suspension 22, ) is supplied to S. Also, when compressed air is exhausted from the suspension, unit, and
1 exhaust solenoid valve 1 as shown by each dashed arrow in the figure
9, the compressed air is discharged to the atmosphere.

Note that a redeep tank 20 is connected to the dryer 12, and a portion of the compressed air is supplied from this redeep tank 20 to each suspension unit S via an air supply solenoid pulp 21.

Further, as shown in FIG. 1, a vehicle height sensor 22 is provided, and this vehicle height sensor 22 is attached to the lower 7-m 23 of the front right suspension of the vehicle to measure the front vehicle height of the vehicle. A front vehicle height sensor 22F detects the rear vehicle height of the vehicle, and a rear vehicle height sensor 22 that is attached to the lateral rod 24 of the rear left suspension of the vehicle and detects the rear vehicle height of the vehicle.
These vehicle height sensors 2
Vehicle height adjustment control i1S from 2F and 22B! A front vehicle height detection signal and a rear vehicle height detection signal are supplied to the control unit 25 of -t and te.

Each sensor 22F in the vehicle height sensor 22.

223 connects one of the Hall IC element and the magnet to the wheel FA.
The sensor is attached to the vehicle body BIIIK on one side and the other side to detect the distance from the normal vehicle height level and the low or high vehicle height level, respectively. Note that there is no problem with using other types of vehicle height sensors, such as those using phototransistors.Furthermore, the speedometer 26 has a built-in vehicle speed sensor 21, and this sensor 27 detects the vehicle speed. A detection signal is supplied to the control unit 25. Mechanical speedometers use a reed switch type vehicle speed sensor, and electronic speedometers use a transistor-based open collector output type sensor. used.

Further, an acceleration sensor 28 is provided as a vehicle attitude sensor for detecting changes in the attitude of the vehicle body. 28 is designed to detect changes in the pitch, roll, and yaw of the vehicle body on the car's springs. For example, when there is no acceleration, K is in a state where the weight is hanging down, and the light from the light emitting diode is blocked by a shielding plate. The structure is such that the absence of acceleration can be detected by blocking the light and preventing it from reaching the photodiode.

When acceleration acts on the front and back, left and right, or up and down, the weight tilts or moves,
The acceleration state of the vehicle body is detected.

32 is a steering sensor that detects the rotational speed of the steering wheel 330, that is, the steering speed; 34 is an accelerator sensor that detects the operation speed of the accelerator pedal of the engine (not shown); and 35 is connected to the reserve tank 20 through a three-way switching valve 36. It is a pneumatic drive mechanism that communicates with the reserve tank 20 and rotates the control rod 8, and the three-way switching valve 36 is set in a position where the pneumatic drive mechanism 35 and the reserve tank 20 are communicated with each other by signals from the control 22 and 25. Either one of the positions communicating the drive mechanism 35 and the atmosphere can be selected, and this has the function of rotating the control rod 3 in the opposite direction to a predetermined position and converting it from a soft state to a hard state. Further, 41 is a door switch that is turned on when the door is opened and turned off when the door is closed, and its operation signal is output to the controller 25. Note that an air cylinder type drive mechanism may be used instead of the solenoid type drive mechanism 200. Also,
The symbol LP indicates the boundary between the engine room (to the left of the broken line LF) and the passenger compartment (between the broken lines LF and LR), and LR indicates the boundary between the single compartment and the trunk room (to the right of the broken line LR). ing. Further, reference numeral 30 indicates a bump stopper for preventing damage to the wall surface of the main air spring chamber 3 due to the relative rise of the cylinder of the shock absorber 1 on rough roads or the like. Reference numeral 31 is a mode selection switch serving as a high vehicle height selection switch.

By the way, this mode selection switch 3 can switch between an auto mode in which the vehicle height is automatically controlled to a normal vehicle height or a low vehicle height, and a high mode in which the vehicle height is controlled to a high vehicle height.

Next, one operation will be explained. The flowchart shown in FIG. 3 represents the operations performed by controls 22 and 25. First, in step SI, it is determined whether the vehicle height is being adjusted.

This is determined by whether or not the rear solenoid pulp 14 or the front solenoid pulp 15 is on.

If rNOJ is determined in this step S1, the process proceeds to step S2 where the vehicle speed detected by the vehicle speed sensor 27 is 3.
It is determined whether it is less than or equal to ky'b. Through the processing in step S2, it is determined whether the vehicle is stopped or not. This station, Gu S2
If rYEsJ is determined in step S3, it is determined whether the door switch 41 is on, that is, the door is open. If rNOJ is determined in this step S3, that is, it is determined that the door is closed, the process proceeds to step S4, and vehicle height adjustment is prohibited. First, the rear solenoid valve 14 and the front solenoid valve 15 are prohibited from being turned on. This is because no one gets on or off the train when the door is closed. On the other hand, if rYEs J is determined in step S3, the process proceeds to step S5, where it is determined whether or not the determination regarding the vehicle height start is satisfied.

If the determination is ``YESJ'' in step 85, the process proceeds to Stella fs 13 and vehicle height adjustment is executed.

〔Effect of the invention〕

As detailed above, according to the present invention, even if the vehicle body moves at a speed of 3 kB/h or less after the stop logic is established, vehicle height adjustment is prohibited until the door is opened, so unnecessary vehicle height and
It is possible to provide an electronically controlled suspension device that can prevent adjustment from starting.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an electronically controlled suspension device according to the present invention, FIG. 2 is a schematic diagram of an automobile equipped with this device, and FIG. 3 is a flowchart for explaining the operation of one embodiment. 11...Compressor, 22...Vehicle height sensor, 25
... Conte cool unit, 27 ... Vehicle speed - + = 7
+, 41...door switch. Applicant's agent Patent attorney Takehiko Suzue Figure 3

Claims (1)

[Claims] A hydraulic suspension unit that is interposed between a wheel side member and a vehicle body side member and has a vehicle height adjustment fluid chamber, a vehicle speed sensor that detects vehicle speed, a door switch that detects opening and closing of a door, and the above-mentioned A vehicle height adjusting means for adjusting the vehicle height by controlling the supply and discharge of air to the fluid chamber for vehicle height adjustment of the hydraulic suspension unit; an electronically controlled suspension device comprising means for prohibiting vehicle height adjustment by the vehicle height adjusting means when it is determined that the vehicle height adjusting means is closed.