JPS6312802B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a kneeling device for adjusting the vehicle height of a large air suspension vehicle such as a bus when passengers are ascending and descending.

Air suspension vehicles generally have left and right bellows for air springs that are supplied with air from the main air tank through a leveling valve, and when the vehicle height is lowered, the leveling valve communicates between the main air tank and the bellows. When the vehicle height increases, the leveling valve opens to the exhaust side to remove air from the bellows and lower the vehicle height, so the vehicle height is always kept constant. On the other hand, when passengers on a bus are going up and down, a lower vehicle height is desirable because it makes it easier for passengers to go up and down. In this case, it is desirable to lower the vehicle height by exhausting the air from the air spring bellows of an air suspension vehicle. However, if all the air in the bellows is removed, it takes a long time to return the vehicle height to its original height and a large amount of air is wasted, which is uneconomical.

An object of the present invention is to lower the vehicle height by exhausting the air spring bellows of an air suspension vehicle, and to shorten the return time by stopping the exhaust in the bellows at a predetermined level of the vehicle height. An object of the present invention is to provide a kneeling device for an air suspension vehicle that can perform kneeling.

Embodiments of the present invention will be described in detail with reference to the drawings. The drawings show a kneeling device 10 for an air suspension vehicle according to the present invention, and the air suspension vehicle has a kneeling device 10 provided between a frame and left and right front wheels. Equipped with bellows 12, 12' for air springs,
These bellows 12, 12' are supplied with air from a main air tank (not shown) through a well-known leveling valve 14 and surge tank 16 that open and close according to the vehicle height, or are evacuated through the leveling valve 14 to maintain the specified position of the vehicle. Maintain vehicle height. Note that similar bellows are provided on the rear wheels of the vehicle to maintain a predetermined vehicle height. Incidentally, reference numeral 18 is a protection valve.

The kneeling device 10 of the present invention includes a cut valve 20 with an exhaust port provided between a bellows 12 and a surge tank 16 on the side having an elevator opening of an air suspension vehicle, and a cut valve 20 with an exhaust port provided between a leveling valve 14 and a surge tank 16. Cut valve 22 provided
It consists of. In the illustrated embodiment, the surge tank 16 has divided chambers 16A, 16B corresponding to the bellows 12, 12', and the inlet 20a of the cut-off valve 20 has a divided chamber 16A corresponding to the bellows 12 of the surge tank 16. The outlet 20b of the cut valve 20 is connected to the bellows 12. The inlet 22a of the cut valve 22 is connected to the leveling valve 14, and the cut valve 22
The outlet 22b is the divided chamber 16 of the surge tank 16.
A and 16B are respectively connected. Note that the cut valve 20 closes the outlet 2 when the inlet/outlet is closed.
0b and the exhaust port 20c communicate with each other to remove the air inside the bellows 12.

The kneeling control means 24 includes a cut valve 2
This control air supply source 2 includes a control air supply source 26 that supplies control air for controlling the opening and closing of 0 and 22.
In the illustrated embodiment, reference numeral 6 comprises a solenoid valve 28 and a kneeling switch 30 for giving an opening/closing command to the solenoid valve. The solenoid valve 28 is connected to a control air tank (not shown), and is also connected to a kneeling switch 30.
is connected to the coil of the solenoid valve 28 in series with the battery power supply 32. In the illustrated embodiment, the kneeling control means 24 further comprises a throttle member 34 disposed downstream of the solenoid valve 28, which throttle member 34 causes the control air to abruptly pass through the cut valve 20, when the solenoid valve 28 opens. 22.

The kneeling device 10 of the present invention includes an exhaust valve 36 connected to the exhaust port 20c of the cut valve 20 with an exhaust port, and an exhaust control means 38 that closes the exhaust valve 36 when the vehicle height of the air suspension vehicle falls below a predetermined value. It also has the following. In the illustrated embodiment, the exhaust valve 36 is a solenoid valve, and the exhaust control means 38 is configured, for example, to respond to the expansion and contraction of the bellows 12 so that the vehicle height is below a predetermined value (a height convenient for passengers to ascend and descend). Level switch 4 that opens depending on length
One end of the level switch 40 is connected to the battery power supply 32 via the kneeling switch 30, and the other end is connected to the coil of the exhaust valve 36.

Next, to describe the operation of the kneeling device, during normal driving, the kneeling switch 30 is open and the solenoid valve 28 is open, so the cut valve 20,
Control air is supplied to the cut valves 20 and 22, and their inlets and outlets communicate with each other, so that the bellows 12 and 12' are filled with air to maintain the vehicle height set by the leveling valve 14. ing. In this case, level switch 4
0 is closed, but the kneeling switch 30 is open, so the exhaust valve 36 is closed. Kneeling switch 30 for raising and lowering passengers at the stop
When the solenoid valve 28 is closed and the control air is exhausted, the cut valves 20 and 22 block the inlet and outlet ports, and at the same time, the outlet 2 of the cut valve 20 is closed.
0b and the exhaust port 20c, and the exhaust valve 3
6 opens, the air within the bellows 12 is exhausted through the cut valve 20 and the exhaust valve 36. When the vehicle height reaches a predetermined value or less, the level switch 40
opens and closes the exhaust valve 36, so air is no longer removed from the bellows 12. When the kneeling switch 30 is opened after the passenger finishes raising and lowering the vehicle at a low vehicle height in this manner, the solenoid valve 28 opens and control air is gradually supplied to the cut valves 20 and 22 through the throttle member 34. Therefore, the cut valves 20 and 22 gradually open their inlets and outlets, and air is gradually sent to the bellows 12 again, returning the vehicle to a predetermined vehicle height. In this case, since sufficient air is left in the bellows 12 by the closing operation of the exhaust valve 36, the vehicle height can be quickly restored. Note that since the leveling 14 opens during kneeling, the cut valve 22 is provided to prevent air from being sent to the bellows 12'.

In the above embodiment, only one bellows 12 is evacuated during kneeling, which is preferable since there is little waste of air. However, the same effect can be obtained even if only the other bellows 12' is evacuated.
2, 12' may be exhausted during kneeling. In this case, it is necessary to provide an exhaust valve to exhaust both bellows.

According to the present invention, as described above, air is removed from the bellows when a passenger is going up or down to lower the vehicle height, which is convenient for raising and lowering the vehicle. Since it stops when it reaches that point, there is no wastage of air, which is economical and has the practical benefit of shortening the return time.

[Brief explanation of the drawing]

The drawing is a schematic system diagram of a kneeling device for an air suspension vehicle according to the present invention. 10... Kneeling device, 12, 12'... Bellows, 14... Leveling valve, 16... Surge tank, 20... Cut valve with exhaust port, 2
2... Cut valve, 24... Kneeling control means, 36... Exhaust valve, 38... Exhaust control means, 40... Level switch.

Claims (1)

[Claims] 1. Left and right bellows for air springs to which air is supplied from a main air tank via a leveling valve, and a surge tank provided between the leveling valve and the bellows and communicating with the left and right bellows, respectively. An air suspension vehicle comprising: a cut valve with an exhaust port provided between at least one bellows and the surge tank;
a cut valve provided between the leveling valve and the surge tank; a kneeling control means for controlling opening and closing of the cut valve with an exhaust port; and an exhaust valve connected to the exhaust port of the cut valve with an exhaust port; exhaust control means that closes the exhaust valve when the vehicle height of the air suspension vehicle falls below a predetermined value, and the cut valve with an exhaust port communicates with the one bellows and the exhaust port when the cut valve with an exhaust port is shut off. A kneeling device for an air suspension vehicle characterized by: 2. The air suspension vehicle according to claim 1, wherein the exhaust valve is a solenoid valve, and the exhaust control means comprises a level switch that opens and closes the solenoid valve when the vehicle height is below a predetermined value. kneeling device.