JP2854725B2 - Kneading equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a kneeling device for a vehicle, and more particularly to a kneeling device that suspends wheels on a vehicle body via an air spring and discharges air from the air spring to lower the vehicle height. .

[0002]

2. Description of the Related Art An air spring such as an air bellows can have a lower spring constant than a leaf spring. Therefore, when such an air spring is used as a suspension spring, riding comfort is improved. Therefore, in a large vehicle, particularly a bus, the wheels are suspended from the vehicle body by an air spring.

[0003] The air spring not only can freely change the spring constant by adjusting the amount of air filled therein, but also can arbitrarily adjust the vehicle height by supplying and discharging air in the air spring. Be able to adjust. Therefore, when the air in the air spring is exhausted so as to lower the portion where the entrance is provided especially when getting on and off, the getting on and off performance is improved.

When a bus is put on a car ferry,
The soft air spring may cause the body to wobble and come into contact with the next vehicle. Therefore, in such a case, it is preferable that the air in the air spring be exhausted so that the air is completely exhausted. Therefore, in the conventional buses equipped with an air spring, a kneeling device is provided,
The air in the air spring is discharged as needed.

[0005]

The above-described kneeling operation is performed, for example, by operating a kneeling switch by a driver, and the air in the air spring is discharged. Therefore, if such a kneeling switch is operated by mistake while the vehicle is running, the air spring impairs its vibration damping effect. Alternatively, the vehicle may have an unstable posture. Further, the function of adjusting the vehicle height by the leveling valve is impaired.

Therefore, for example, it is possible to perform the kneeling operation only when the vehicle is stopped. However, in this case, the vehicle may enter a structure having a low ceiling height, The kneeling operation cannot be performed when passing through a tunnel having a low height. That is, even in the case where the bending kneeling device is provided, in such a case, the vehicle height cannot be reduced by the kneeling device and interference between the ceiling of the structure or the tunnel and the upper part of the vehicle body cannot be prevented.

The present invention has been made in view of such a problem, and does not perform the kneeling operation during the normal running of the vehicle, and performs the kneeling operation only at an extremely low speed or when the vehicle is stopped. It is an object of the present invention to provide a kneeling device adapted to be used.

[0008]

SUMMARY OF THE INVENTION The present invention relates to a kneeling device which suspends wheels on a vehicle body via an air spring and discharges air from the air spring to lower the vehicle height. A leveling valve connected between the air spring and maintaining a vehicle height at an appropriate value; a leveling valve connected between the leveling valve and the air spring to close an exhaust port and to connect the leveling valve to the air spring; An exhaust valve configured to communicate with an air spring, an exhaust valve configured to cut off communication between the leveling valve and the air spring, and to switch to an exhaust state in which the air spring communicates with the exhaust port, and a signal port of the exhaust valve. Has been
A solenoid valve that supplies a signal pressure to the exhaust valve to switch the exhaust valve, a kneeling switch is connected and a controller that controls the electromagnetic valve, and a vehicle speed that is connected to an input side of the controller and detects a vehicle speed Detecting means;
When the signal pressure is not applied to the exhaust valve through the solenoid valve, the exhaust valve functions as a mere air passage to connect the leveling valve and the air spring and close the exhaust port. ,
When the vehicle height adjusting operation is performed by the leveling valve and the kneeling switch connected to the controller is operated, the vehicle speed is detected only when the vehicle speed detected by the vehicle speed detecting means is equal to or less than a predetermined value. The solenoid valve is switched by a controller to supply a signal pressure to a signal port of the exhaust valve, the exhaust valve cuts off communication between the leveling valve and the air spring, and the air in the air spring exhausts the air. The present invention relates to a kneeling device characterized in that the gas is discharged through an exhaust port of a valve to perform a kneeling operation.

[0009]

Therefore, when the kneeling switch connected to the controller is operated, the solenoid valve is switched only when the vehicle speed detected by the vehicle speed detecting means is lower than a predetermined value, and the signal pressure is supplied to the signal port of the exhaust valve. The exhaust valve cuts off the communication between the leveling valve and the air spring, and the air in the air spring is exhausted through the exhaust port of the exhaust valve to perform the kneeling operation. On the other hand, when the vehicle is traveling normally and the vehicle speed is equal to or higher than a predetermined value, the vehicle speed is detected by the vehicle speed detecting means, and even if the kneeling switch is operated, the kneeling operation is prevented by the controller. Is not switched, and the air in the air spring is not discharged.

[0010]

FIG. 1 is a piping diagram of a bus air suspension device provided with a kneeling device according to an embodiment of the present invention. The axle on the front wheel side is a pair of left and right air springs 1.
Suspended by one. On the other hand, the rear axle is suspended by two air springs 12 and 13 provided on each of the left and right sides. The air springs 11, 12, and 13 are supplied with air from an air tank 14.

The air spring 11 on the front wheel side is connected to an air tank 14 through two types of air pipes 15 and 16. An electromagnetic valve 17 is commonly connected to the left and right of the air pipe 15, and the air pipe 15 is branched right and left downstream of the electromagnetic valve 17 so as to be connected to the air spring 11 via an exhaust valve 18. It has become. On the other hand, a pair of left and right leveling valves 19 is connected to the second air pipe 16, and this leveling valve 19 is connected to the air spring 11 via the exhaust valve 18. ing.

A pair of right and left rear air springs 12, 1
Reference numeral 3 is connected to the air tank 14 via air pipes 21 and 22. The left and right air springs 1 are connected to the left and right air springs 21 in common with the air pipe 21.
The left and right exhaust valves 24 are connected corresponding to 2 and 13, respectively. On the other hand, a leveling valve 25 is commonly connected to the second air pipe 22, and the leveling valve 25 is connected to the air springs 12 and 13 via left and right exhaust valves 24.

The pressures of the front and rear air springs 11, 12 and 13 are detected by low pressure switches 27 and 28.
Are connected to the controller 30.

As shown in FIGS. 1 and 4, a kneeling switch 31, a vehicle speed sensor 32, and an operation display lamp 33 are connected to the controller 30. The controller 30 controls the front and rear solenoid valves 17 and 23.

Next, the structure of the exhaust valves 18 and 24 connected to the solenoid valves 17 and 23 will be described. Since the front and rear exhaust valves 18 and 24 have the same structure, the structure of the front exhaust valve 18 will be described here. Exhaust valve 18
2 and FIG. 3, the casing 36 has an upper port 37, a side port 38, a signal port 39, and an exhaust port 40. The upper port 37 is connected to the leveling valve 19. Side port 38 is air spring 11
It is connected to the. The signal port 39 is connected to the solenoid valve 17. The exhaust port 40 is open to the atmosphere.

A plunger 43 is slidably housed in the casing 36. The plunger 43 is pressed upward by a spring 44 and abuts on the lower surface of the inlet valve 45 facing the upper port 37, thereby closing the center hole 46. When a signal pressure is applied to the chamber 47 from the solenoid valve 17 through the signal port 39, the plunger 43 moves downward against the coil spring 44, and the upper end of the plunger 43 separates from the inlet valve 45 and the center hole 46. Is communicated with the side port 38.

In the above configuration, when the solenoid valves 17 and 23 shown in FIGS. 1 and 4 are opened by a signal from the controller 30 and signal pressure is supplied to the exhaust valves 18 and 24, these exhaust valves are opened. Air is discharged from the air springs 11, 12, and 13 by 18 and 24, and a kneeling operation is performed.

On the other hand, when no signal is supplied from the controller 30, the solenoid valves 17 and 23 are closed, and the exhaust valves 18 and 24 do not perform an exhaust operation. In such a case, the exhaust valves 18 and 24 function simply as communication paths, and communicate with the leveling valves 19 and 25 and the air springs 11, 12, and 13. Therefore, the leveling valves 19 and 25 adjust the amount of air in the front and rear springs 11, 12, and 13, and the operation of adjusting the vehicle height is performed. That is, usually the leveling valve 1
The vehicle height is always maintained at an appropriate value by means of 9, 25.

Next, the solenoid valve 1 is controlled by the controller 30.
The kneeling operation for lowering the vehicle height by opening 7, 23 will be described. When the driver operates the kneeling switch 31 connected to the controller 30, a current flows from the controller 30 to the lower terminals of the front and rear solenoid valves 17 and 23 shown in FIG. be opened. Then, a signal pressure is supplied into the chamber 47 through the signal port 39 of the exhaust valve 18 shown in FIGS. Then, the plunger 43 moves downward against the spring 44 to be in a state as shown in FIG. That is, plunger 4
3 is separated from the inlet valve 45 facing the port 37,
This causes the inlet valve 45 to close the port 37. Then, the center hole 46 of the plunger 43 and the port 38 communicate with each other.

When the exhaust valve 18 is opened by the signal pressure as described above, the compressed air in the air spring 11 passes from the port 38 through the center hole 46 of the plunger 43 and passes through the exhaust port 40 provided at the lower portion of the casing 36. Will be discharged through Rear air spring 12, 1
The compressed air in the rear exhaust valve 24 performs a similar operation.
Is discharged through. As a result, the vehicle height is reduced, and a kneeling operation is performed.

Moreover, such a kneeling operation is performed by a computer built in the controller 30.
Based on the flowchart shown in FIG. 6, the operation is performed only when the vehicle is stopped or at an extremely low speed.

The computer in the controller 30 reads the vehicle speed by the vehicle speed sensor 32, and reads the vehicle speed.
It is determined whether it is 0 km / h or less. Vehicle speed is 20k
If it is greater than m, no kneeling operation is performed. If the vehicle speed is equal to or less than 20 km, the output of the kneeling switch 31 is further read to determine whether or not the vehicle is descending.
Then, in the case of the descending operation, the solenoid valves 17 and 23 are opened. On the other hand, in the case of the rising operation, the solenoid valves 17 and 2
3 is closed. The raising operation is achieved by closing the exhaust valves 18, 24 and by the function of the leveling valves 19, 25.

As described above, the kneeling device according to the present embodiment does not perform the kneeling operation as shown in FIG. 6 when the vehicle is running at normal or high speed. On the other hand, when the vehicle speed is extremely low or the vehicle is stopped, the kneeling operation is performed. Therefore, for example, when entering a structure with a low ceiling or passing through a tunnel with a low ceiling, lower the vehicle height and slowly prevent interference between the upper part of the body and the ceiling of the structure or tunnel. It becomes possible to run.

Further, since the kneeling can be arbitrarily performed even while the vehicle is stopped, the height of the vehicle may be lowered in advance when the passenger gets on and off, so that the getting on and off may be improved. If the front and rear solenoid valves 17 and 23 are controlled separately,
It is also possible to perform kneeling of only the air spring having the entrance.

In the above-described embodiment, the output of the vehicle speed sensor 32 is read by the computer in the controller 30 to determine whether the vehicle speed is 20 km / h or less. The pickup coil 50 shown in FIG. Since the pickup coil 50 detects the rotation speed of the wheel, the pickup coil 5
By counting the output pulse of 0, it is possible to detect whether the vehicle is stopped or whether the speed of the vehicle is lower than a predetermined value.

FIG. 7 shows another embodiment. In this embodiment, the vehicle speed is estimated from the gear position of the transmission and the position of the parking lever instead of reading the vehicle speed and the rotation speed of the wheels. I have. The controller 30 includes a first speed detection switch 51 of the transmission,
The reverse detection switch 52, the neutral detection switch 53, and the parking switch 54 for detecting that the parking lever is pulled are connected.

Therefore, when the switches 51 and 52 are ON, the controller 30 determines that the vehicle speed is extremely low. When the neutral detection switch 53 or the parking switch 54 is ON, the controller 30 detects that the vehicle is stopped. The kneeling operation is performed only in these cases.

Therefore, even in such an embodiment, the same operation and effect as in the above embodiment can be obtained. The front and rear low pressure switches 27 and 28 connected to the controller 30 are switches that are turned on when the pressure in the front and rear air pipes becomes, for example, 3.0 kg / cm ² or less, and monitors that the vehicle has dropped. I am trying to do it.

[0029]

As described above, according to the present invention, a leveling valve connected between an air pressure source and an air spring to maintain a vehicle height at an appropriate value, and a leveling valve connected between the leveling valve and the air spring are provided. An exhaust valve that closes the exhaust port and communicates with the leveling valve and the air spring, and an exhaust valve that shuts off communication between the leveling valve and the air spring and switches to an exhaust state that communicates the air spring with the exhaust port. A solenoid valve that is connected to the signal port of the valve and switches the exhaust valve by supplying signal pressure to the exhaust valve, a kneeling switch is connected, and a controller that controls the electromagnetic valve and is connected to the input side of the controller And vehicle speed detecting means for detecting the vehicle speed, and no signal pressure is applied to the exhaust valve through the solenoid valve. In this case, the exhaust valve functions as a mere air passage, connects the leveling valve to the air spring, closes the exhaust port, adjusts the vehicle height by the leveling valve, and activates the kneeling switch connected to the controller. When operated, the solenoid valve is switched by the controller only when the vehicle speed detected by the vehicle speed detecting means is equal to or lower than a predetermined value, and the signal pressure is supplied to the signal port of the exhaust valve. The communication with the air spring is cut off, and the air in the air spring is exhausted through the exhaust port of the exhaust valve to perform the kneeling operation. Therefore, the kneeling operation is performed only when the vehicle is stopped or when the vehicle speed is equal to or lower than a predetermined value, so that the kneeling operation during normal traveling can be prevented. And, since the kneeling operation is performed when the vehicle speed is equal to or less than a predetermined value, the vehicle enters a structure with a low ceiling or a vehicle passes through a tunnel with a low ceiling. In this case, the kneeling device can be effectively used, the vehicle can be passed at a reduced height, and interference between the upper portion of the vehicle and the ceiling of a structure or a tunnel can be prevented. Such a kneeling operation is performed by switching the electromagnetic valve by the controller, supplying the signal pressure to the signal port of the exhaust valve by the electromagnetic valve, and exhausting the exhaust valve to exhaust the air in the air spring. Therefore, the solenoid valve is composed of a small solenoid valve that supplies the signal pressure applied to the signal port of the exhaust valve, and the current of the coil becomes extremely small,
The switching control of the exhaust valve is performed by the solenoid valve which consumes less power. Also, in the present invention, since the kneeling operation is achieved by performing the exhaust operation using a dedicated exhaust valve, the time required for exhaust can be shortened only by increasing the diameter of the exhaust port of the exhaust valve. it can. As a result, the kneeling operation can be performed quickly, and a kneeling apparatus that can perform power-saving and quick kneeling is provided. In the present invention, an exhaust valve is connected between an air spring that suspends wheels and a leveling valve, and a signal pressure is supplied to the exhaust valve via an electromagnetic valve. Therefore, it is possible to dispose the solenoid valve at a position far from the suspension device, and it is not necessary to dispose the solenoid valve in the vicinity of a wheel that is easily affected by muddy water or the like. Therefore, it is not necessary to wire the solenoid valve disposed at a position where the use environment is inferior, and it is possible to prevent the occurrence of trouble in the electric system. Also, an exhaust port is provided on an exhaust valve that performs an exhaust operation, and when a signal pressure is supplied to a signal port of the exhaust valve, the exhaust valve is switched from a communicating state to an exhaust state, and air in an air spring is exhausted by the exhaust valve. Since the air is discharged through the exhaust port, there is no need to connect a branch pipe to the air pipe and connect an exhaust valve to the branch pipe. Also, when signal pressure is supplied, this exhaust valve cuts off the communication between the leveling valve and the air spring, so the exhaust valve also serves as a cut valve, and the cut valve can be omitted. , The number of valves is reduced. This also has the advantage that the air piping is simplified and the cost of the kneeling device can be reduced. In the present invention, a dedicated exhaust valve for performing a kneeling operation is connected between the leveling valve and the air spring as described above,
The kneeling operation is achieved by an exhaust valve independent of the leveling valve. Therefore, it is not necessary to add an elevating mechanism or a rotating mechanism to the leveling valve, and the mounting structure of the leveling valve does not become complicated. When the exhaust valve is switched to the normal communication state immediately after the kneeling operation, the leveling valve and the air spring come into communication through the exhaust valve,
It is possible to immediately return to the normal leveling operation.

[Brief description of the drawings]

FIG. 1 is a block diagram of a kneeling device according to a first embodiment of the present invention.

FIG. 2 is a front view of an exhaust valve of the kneeling device.

FIG. 3 is a side sectional view of the exhaust valve.

FIG. 4 is a block diagram of a control circuit of the kneeling device.

FIG. 5 is a block diagram of a control circuit according to a second embodiment.

FIG. 6 is a flowchart showing the operation of the controller.

FIG. 7 is a block diagram of a control circuit according to a third embodiment.

[Explanation of symbols]

 Reference Signs List 11 air spring (front) 12, 13 air spring (rear) 14 air tank 15, 16 air pipe 17 solenoid valve (front) 18 exhaust valve 19 leveling valve 21, 22 air pipe 23 solenoid valve (rear) 24 exhaust valve 25 leveling valve 27 Low pressure switch (front) 28 Low pressure switch (rear) 30 Controller 31 Kneeling switch 32 Vehicle speed sensor 33 Operation indicator lamp 36 Casing 37 Upper port 38 Side port 39 Signal port 40 Exhaust port 43 Plunger 44 Spring 45 Inlet valve 46 Center Hole 47 Chamber 50 Pickup coil 51 1st speed detection switch 52 Reverse detection switch 53 Neutral detection switch 54 Parking switch

Claims (1)

(57) [Claims] 1. A kneeling device for suspending wheels on a vehicle body via an air spring and discharging air from the air spring to lower the vehicle height, wherein a knee connection is provided between an air pressure source and the air spring. A leveling valve for maintaining the vehicle height at an appropriate value; a communication state connected between the leveling valve and the air spring for closing an exhaust port and communicating the leveling valve with the air spring. An exhaust valve that shuts off the communication between the leveling valve and the air spring and switches to an exhaust state in which the air spring communicates with the exhaust port; and an exhaust valve connected to a signal port of the exhaust valve. When a knee pressure switch is connected to a solenoid valve that switches the exhaust valve by supplying a signal pressure, Both comprising a controller for controlling the solenoid valve, and a vehicle speed detecting means connected to the input side of the controller for detecting a vehicle speed, when no signal pressure is applied to the exhaust valve through the solenoid valve. The exhaust valve functions as a mere air passage to connect the leveling valve and the air spring and close the exhaust port,
A vehicle height adjustment operation is performed by the leveling valve, and when the kneeling switch connected to the controller is operated, the vehicle speed is detected only when the vehicle speed detected by the vehicle speed detection unit is equal to or less than a predetermined value. The solenoid valve is switched by a controller to supply a signal pressure to a signal port of the exhaust valve, the exhaust valve cuts off communication between the leveling valve and the air spring, and the air in the air spring exhausts the air. A kneeling device characterized by being discharged through an exhaust port of a valve and performing a kneeling operation.