JPS643686B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to an air suspension device.

Recently, an air suspension device as shown in FIG. 1 has been proposed. That is, 1 is an air compressor driven by an internal combustion engine or an electric motor, and compressed air from this air compressor 1 is guided to a tank 4 through a passage 3 with a dryer device 2 interposed therebetween. ing. The tank 4 is equipped with a pressure switch 5, and when the pressure in the tank 4 reaches a predetermined value, the pressure switch 5 turns off the power supply A that drives the compressor 1, and turns off the compressor 1.
When the pressure drops below a predetermined value, the compressor 1 is turned on and the compressor 1 is driven to keep the pressure inside the tank 4 constant. A check valve 6 for preventing backflow from the tank 4 is provided in a passage 3 between the dryer device 2 and the tank 4 at a position near the tank 4. The compressed air in the tank 4 is supplied to air chambers 10, 10 of the suspension bodies 9, 9 through a passage 8 with an air supply valve 7 interposed therebetween. The air supply valve 7 is connected to a vehicle height adjustment sensor 11 and a module 12, and opens when the vehicle height becomes low to supply compressed air to the air chambers 10, 10 of the suspension bodies 9, 9. It's summery. Reference numeral 13 denotes a detour passage in which a relief valve 14 is interposed to guide compressed air from the air chambers 10, 10 of the suspension bodies 9, 9 to the passage 3. The exhaust side of the suspension bodies 9, 9 is led into the tank 4 through a detour passage 13 with a relief valve 14 interposed therein, and through a dryer device 2 or a passage 3 with a check valve 6 interposed therebetween. There is. Further, the exhaust gas that has passed through the dryer device 2 is exhausted to the outside through a passage 16 with an exhaust valve 15 interposed therebetween. The exhaust valve 15 also has a sensor 11 and a module 12 similar to the air supply valve 7.
The compressed air in the air chambers 10, 10 of the suspension bodies 9, 9 is connected to a detour passage 13, which is connected to a relief valve 14, and opens when the vehicle height increases.
The air is discharged to the outside through a passage 16 having a dryer device 2 and an exhaust valve 5 interposed therebetween. At this time, the compressed air from the air chambers 10, 10 of the suspension bodies 9, 9 passing through the dryer device 2 regenerates the chemical (such as silica gel) used as a dryer in the dryer device 2.

In the above structure, a constant amount of compressed air is always stored in the tank 4 from the compressor 1 through the passage 3 in which the dryer device 2 is interposed, by the action of the pressure switch 5. When passengers get off the vehicle or cargo is removed from the vehicle, the load on the vehicle is reduced and the height of the vehicle becomes higher. When the vehicle height becomes higher than a predetermined value, a sensor 11 detects this and operates a module 12 to open an exhaust valve 15. Therefore, the compressed air in the air chambers 10, 10 of the suspension bodies 9, 9 is discharged to the outside through a passage 16 that includes a relief valve 14, a dryer device 2, and an exhaust valve 15, and the vehicle height is adjusted to the standard position. is exhausted until

However, in the air suspension device having such a configuration, when the air pressure in the tank 4 falls below a certain pressure, the air compressor 1 is activated and air is supplied to the tank 4.

Therefore, when the air supply valve 7 opens, the air pressure in the air chambers 10, 10 of the suspension bodies 9, 9 increases, and when it reaches the same pressure as the air in the tank 4, any further pressure increase is caused by the air compressor 1. Since the tank 4 and the air chambers 10, 10 of the suspension bodies 9, 9 had to be pressurized at the same time, it took a lot of time to raise the vehicle height accordingly. This is especially true when the air pressure in the tank 4 is low.

In view of the above-mentioned shortcomings, this proposal includes a solenoid valve interposed in the passage between the air compressor and the tank.
In addition, the air compressor is equipped with a suction valve that sucks air from the tank, and the solenoid valve is opened in response to a rising signal, and the air in the tank passes through the air compressor.
The air in the tank is supplied to the air chamber of the suspension body through a dryer device, and even if the air pressure in the tank is lower than the air pressure in the air chamber of the suspension body, the air in the tank is pressurized by the air compressor and the air is supplied to the suspension body. Supplied to the air chamber of the system body,
Increase its internal pressure. Also, when the air pressure in the tank becomes almost equal to atmospheric pressure, the air intake valve opens and the air is pressurized by the air compressor and supplied to the air chamber of the suspension body, which speeds up the vehicle height rise time. To obtain an air suspension system that can effectively utilize air pressure in a tank until it reaches atmospheric pressure.

The present invention will be explained below using the embodiment shown in FIG.

The main difference from the embodiment shown in FIG.
The base port 7a of the air supply valve 7 is communicated with the discharge valve 19 of the air compressor 1, the first port 7b is communicated with the air chambers 10, 10 of the suspension, and the third port 7c is communicated with the tank 4. The base port 7a is connected to the first port 7b or the second port 7c.
so that it can be switched and communicated,
When the vehicle height is increased, the base port 7a and the first port 7b are connected, and when the tank internal pressure is higher than the set value, the solenoid valve 17 is opened and released from the tank, and when it is lower, it is closed. When the air compressor 1 operates, compressed air is supplied to the air chambers 10, 10 from the air intake valve 20 provided between the solenoid valve 17 and the air compressor 1. While connecting the port 7a to the second port 7c, the solenoid
The valve 17 is closed, the atmosphere introduction valve 20 is opened, and the atmosphere is supplied from the atmosphere introduction valve 20 to the tank 4 until the tank internal pressure reaches a predetermined pressure.

That is, the rising signal causes solenoid valve 1 to
7 is opened, the base port 7a of the air supply valve 7 is connected to the first port 7b, and the air in the tank 4 is sucked in and compressed by the suction valve 18 of the air compressor 1, and the compressed air is Passage 2 via discharge valve 19
1 and 22, the air reaches the dryer device 2, passes through the check valve 23 and the air supply valve 7, and is supplied to the air chambers 10 and 10 of the suspension bodies 9 and 9.

When the pressure becomes lower than a predetermined level, the solenoid valve 17 is closed, air is sucked in through the air intake valve 20, and the air compressed by the air compressor 1 is passed through the passage 21,
22, the dryer device 2, the check valve 23, the air supply valve 7, and the passages 24, 25 to the air chambers 10, 10 of the suspension bodies 9, 9.

The exhaust valve 15 is opened by the descending signal, and the first
As shown in the figure, the air in the air chambers 10, 10 of the suspension bodies 9, 9 is of course exhausted through the dryer device 2. In the embodiment shown in the drawings, the atmosphere inlet valve 20 is replaced by a solenoid valve 17 in the passage 3.
Although the air introduction valve 20 is provided between the intake valve 18 of the air compressor 1 and the air intake valve 18 of the air compressor 1, the air introduction valve 20 may be provided in the air compressor 1.

Note that the passage 2 is branched from the passage 3 and directly communicates with the air chambers 10, 10 of the suspension bodies 9, 9.
6 (dotted line) may be provided.

In this case, if the tank internal pressure is higher than the suspension internal pressure, the air will not pass through the air compressor 1, dryer device 2, and air supply valve 7, and there will be less resistance, so air can be supplied more quickly. Furthermore, the pressure switch can be installed anywhere from the discharge valve of the air compressor to the tank.

Note that FIG. 3 is a graph showing the operating state of each part.

As is clear from the above description, the present invention has the following effects.

(1) The air in the tank can be effectively used for vehicle height adjustment until the air pressure approaches atmospheric pressure.

(2) Air pressure in the air chamber of the suspension body can be increased significantly faster with an air compressor of the same capacity.

(3) If a rise signal is issued even when the air pressure in the tank is low, it is only necessary to increase the pressure in the air chamber of the suspension body, so the vehicle height rises quickly.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a conventional air suspension device, FIG. 2 is a block diagram of the air suspension device of the present invention, and FIG. 3 is a graph diagram showing the operating state of each part during ascending and descending. DESCRIPTION OF SYMBOLS 1... Air compressor, 2... Dryer device, 3... Passage, 4... Tank, 5... Pressure switch, 6... Check valve, 7... Air supply valve, 7a... Base port, 7b...
1st port, 7c...2nd port, 8...passage, 9...
Air suspension body, 10...Air chamber, 1
1...Vehicle height adjustment sensor, 12...Module, 1
3...Detour passage, 14...Relief valve, 15...Exhaust valve, 16...Passage, 17...Solenoid valve, 18
...Suction valve, 19...Discharge valve, 20...Atmospheric introduction valve, 2
1, 22... Passage, 23... Check valve, 24, 2
5, 26...Aisle.

Claims (1)

[Claims] 1 Consists of a base port that communicates with the discharge valve of the air compressor, a first port that communicates with the air chamber of the suspension, and a second port that communicates with the tank, and the base port is switched to communicate with the first port or the second port. It is equipped with an air supply valve, a solenoid valve that opens and closes a passage between the tank and the air compressor's intake valve, and an atmosphere intake valve installed between the solenoid valve and the air compressor. When the pressure is up, the base port and the first port are connected, and when the tank internal pressure is high, the solenoid valve opens and the air is supplied from the tank, and when it is low, it is closed and the air inlet valve is connected to the air compressor. During operation, compressed air is supplied to the air chamber, and after the vehicle height has been raised, the base port is connected to the second port, the solenoid valve is closed, and the air intake valve is opened to reduce the tank internal pressure. An air suspension device that supplies atmospheric air to a tank from an atmospheric intake valve by driving an air compressor until it reaches a predetermined pressure.