JP2007030597A - Air suspension device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inexpensive device which eliminates the need for a solenoid, acceleration sensor, electronic controller or the like which are used for driving a valve. <P>SOLUTION: An air suspension device is provided with an air spring 3 which is provided between a car body and each wheel and supports the car body. The air spring 3 is provided with housings 21, 23, 24 forming air spring chambers 34, 35 inside, a partition member 26, a valve 31, and a pendulum 29. The partition member 26 divides the air spring chamber into the first and the second air spring chambers 34, 35 and has a continuous hole 27 connected to the first and the second air spring chambers. Then the valve 31 connects or intercepts the space between the first and the second air spring chambers by opening and closing the continuous hole 27, and switches spring constants. The pendulum 29 is operated by the acceleration acting on the car body, and the valve 31 is constituted so that it is brought into opening and closing operation mechanically in synchronization with the operation of the pendulum. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an air suspension device having an air spring.

  2. Description of the Related Art In recent years, air suspension vehicles, in which riding comfort is improved by using an air suspension as a suspension device of a vehicle body, have been mainstream in sightseeing buses and large passenger cars that frequently travel at high speeds. Since the air suspension vehicle uses air, which is a compressible fluid, in the air spring, it is possible to provide a superior ride comfort compared to a normal device using a leaf spring.

If such an air suspension is used, the spring constant of the air spring can be adjusted by adjusting the volume of the air chamber in the air spring. For example, Non-Patent Document 1 proposes an electronically controlled air suspension using an air spring. The air spring includes a main chamber configured integrally with the shock absorber, a separate sub tank, and a solenoid valve that communicates or blocks between the main chamber and the sub tank, and switches the air volume in two stages to switch the spring constant. Prepare. In accordance with signals from various sensors (for example, an acceleration / deceleration sensor and a steering angle sensor) that detect the traveling state, the solenoid valve is controlled to open and close so as to obtain an appropriate suspension state. By opening the solenoid valve, the main chamber communicates with the sub-tank, and the spring volume is reduced by increasing the air volume (spring constant software), while the solenoid valve is closed and the main valve is closed. The communication between the chamber and the sub tank is cut off, the air volume is reduced, and the spring constant is increased (spring constant hard).
"Vehicle movement performance and chassis mechanism" (issued September 10, 1994, Grand Prix, Inc.)

In the above-described conventional electronically controlled air suspension device, more advanced control is possible, but an acceleration sensor for detecting vehicle acceleration, a plurality of solenoid valves that change the spring constant by changing the volume of the air spring, and electromagnetic A controller (signal processing circuit and calculation program) for driving and controlling the valve was necessary. As a result, the cost of this apparatus is increased, the control circuit and control software for complicated functions become more complicated, and much consideration and cost are required to ensure its reliability.

  For this reason, it is necessary to limit functions in order to reduce costs. A high-performance, high-priced air suspension system is effective for high-class sightseeing buses, but for familiar microbuses and leisure vehicles, it only improves the anti-rolling and pitching characteristics as well as the ride comfort. But it can be effective. Furthermore, each element needs to be simplified. However, since automobile parts are required to be safe and reliable, there is a limit to the simplification without reducing the quality.

  Therefore, the present invention has a technical problem of reducing the cost and improving the reliability by reducing the number of electrical components.

In order to solve the above-mentioned problem, the technical means taken in the invention of claim 1 includes an air spring, a housing in which an air spring chamber is formed, and the air spring chamber as first and second air spring chambers. A partition member having a communication hole that is divided and communicated with the first and second air spring chambers, and opens and closes the communication hole to communicate or block between the first and second air spring chambers; And a pendulum that operates by acceleration acting on the vehicle body, and the valve is configured to mechanically open and close in conjunction with the operation of the pendulum.

  According to this technical means, since the valve is mechanically opened and closed in conjunction with the operation of the pendulum operated by the vehicle body acceleration, a solenoid, an acceleration sensor, an electronic controller, and the like that drive the valve used conventionally Becomes unnecessary and the apparatus becomes inexpensive.

  In claim 1, as shown in claim 2, the pendulum extends in a substantially vertical direction of the vehicle body in a state where no acceleration acts on the vehicle body, and the valve is integrally provided at an upper end of the pendulum, It is preferable that a balancer for setting the position of the center of gravity is integrally provided at the lower end of the pendulum. According to this configuration, the spring constant of the air spring chamber can be controlled with a simpler configuration.

  In claim 1, as shown in claim 3, the pendulum is pivotally supported by a pivot member fixed to the partition member, and the valve is moved by gravity in a state where no acceleration acts on the vehicle body. It is preferred if it is configured to be held open. According to this configuration, the spring constant of the air spring chamber can be controlled with a simpler configuration.

  In claim 1, as shown in claim 4, the pendulum is configured to operate by a lateral acceleration acting on the vehicle body, and the valve has a predetermined lateral acceleration acting on the pendulum. It is preferable that the communication hole is closed. According to this configuration, rolling of the vehicle can be suppressed with a simple configuration.

  In claim 1, as shown in claim 5, the pendulum is configured to operate in a forward acceleration acting on the vehicle body, and the valve is operated when a predetermined forward acceleration acts on the pendulum. It is preferable that the communication hole is closed. According to this configuration, the pitching of the vehicle can be suppressed with a simple configuration.

    In claim 1, as shown in claim 6, the pendulum is configured to operate in a lateral and forward acceleration acting on the vehicle body, and the valve has a predetermined lateral acceleration and a forward acceleration. Is preferably configured to close the communication hole when acting on the pendulum. According to this configuration, rolling and pitching of the vehicle can be suppressed with a simple configuration.

According to the present invention, since the valve is configured to mechanically open and close in conjunction with the operation of the pendulum operated by the vehicle body acceleration, the solenoid, the acceleration sensor, the electronic controller, and the like that drive the valve that are conventionally used are unnecessary. And the device becomes inexpensive.

The best mode for carrying out the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view showing a configuration of an air spring of the present invention. FIG. 2 is a cross-sectional view showing the operation of the air spring of the present invention, and shows a case where a centrifugal force is acting in the right direction. FIG. 3 is a partial sectional view showing the operation of the air spring of the present invention, and shows a case where a centrifugal force is acting in the left direction. FIG. 4 is a system configuration diagram showing an air suspension configuration of the present invention.

  The present embodiment shown in the system configuration diagram of FIG. 4 shows an example of an air suspension type suspension device for all the front, rear, left and right wheels. The configuration will be described using the right rear wheel as an example. The wheel 1 is supported on the vehicle body by a double wishbone type link mechanism. An air spring 3 is connected between the lower arm 2 of the link mechanism and the vehicle body to constitute a spring mechanism that supports the vehicle body via wheels 1 that are in contact with the ground. The air spring 3 is connected to a leveling valve 5 through a pipe 4. The leveling valve 5 detects the movement of the lower arm 2 through the swing lever 6 and the sensing rod 7, supplies air from the air supply source 9 to the air spring 3 through the pipe 8, and sends air from the air spring 3 to the atmosphere. Air can be discharged to In the above description, the right rear wheel has been described as an example, but the left rear wheel has a target arrangement with the right rear wheel, and the front wheel has the same configuration as the rear wheel.

  As shown in FIG. 1, the air spring 3 includes a boot 21 (housing) that is molded of an elastic body such as rubber. The upper end of the boot 21 is hermetically fixed to an upper support 23 (housing) connected to the vehicle body by a band 22, and the lower end of the boot 21 overlaps with the outer periphery of the piston 24 engaged with the lower arm 2. The piston 24 is hermetically fixed by a ring 25. A main air chamber 34 is formed in the boot 21 and the upper support body, and a sub air chamber 35 is formed in the piston 24. A nipple 36 is installed on the upper support 23 so that air in the main air chamber 34 can be replenished or discharged via the pipe 4.

  A plate 26 (partition member) is fixed to the upper end of the piston 24 to partition the main air chamber 34 and the sub air chamber 35.

The plate 26 is provided with a valve hole (communication hole) 27 communicating with the main air chamber 34 and the sub air chamber 35, and a bearing 28 (pivot support member) is fixed thereto. The pendulum 29 has a balancer 30 at the lower end, and a valve 31 that opens and closes the valve hole 27 is integrally formed at the upper end. The pendulum 29 is pivotally supported by a bearing 28 by a pin 32. . The center of gravity 33 of the pendulum 29 is set so as to be located slightly on the outer diameter side of the piston below the pin 32, and the valve 31 is always kept open by gravity.

  Next, an operation when acceleration such as centrifugal force is applied to the air spring 3 will be described. FIG. 2 shows the operating state of the air spring 3 when a centrifugal force is applied to the right. The rightward centrifugal force 37 is applied to the pendulum 29, and a rightward force is applied to the position of the center of gravity. As a result, the pendulum 29 rotatably supported by the pin 32 swings counterclockwise, and further reaches a state where the valve 31 closes the valve hole 27. In this state, the main air chamber 34 and the sub air chamber 35 are separated from each other, and the spring action in the case of compressing the air spring 3 compresses only the air in the main air chamber 34. The spring constant of increases.

  When the centrifugal force acts on the left side, as shown in FIG. 3, the pendulum 29 swings clockwise by the leftward centrifugal force 38. By this swinging, the valve 31 operates in a more open direction and is not closed. The swing of the pendulum 29 is regulated by contacting one end of the valve hole 27 of the plate 26, that is, the stopper 39. In this state, the main air chamber 34 and the sub air chamber 35 are in communication with each other, and the spring action when compressing the air spring 3 compresses both the air in the main air chamber 34 and the air in the sub air chamber 35. Therefore, the spring constant as an air spring becomes small.

  In the above description, the right rear wheel has been described as an example. However, since the left rear wheel is a target of the right rear wheel, it operates when a centrifugal force is applied to the left. On the other hand, the left and right front wheels have the same structure as the respective rear wheels, and the operation thereof is the same as that of the rear wheels.

  Next, the operation of the air suspension will be described. When the load of the vehicle body increases due to getting on or loading the vehicle, the load is distributed to each wheel, and the load is applied to the air spring 3. As a result, the air in the main air chamber 34 and the sub air chamber 35 is compressed, and the air pressure is increased by reducing the volume of the air to counter the applied load. When acceleration such as centrifugal force is not generated, the main air chamber 34 and the sub air chamber 35 communicate with each other, so that the volume of the air amount is large and acts as a gentle spring action. On the other hand, when acceleration such as centrifugal force is generated, the communication between the main air chamber 34 and the sub air chamber 35 is blocked, so that the volume of the air amount is small and the spring acts as a rigid spring.

  On the other hand, the leveling valve 5 that detects the sinking of the vehicle body as a change in the lower arm 2 supplies air from the air supply source 9 to the air spring 3 via the pipe 8, and the main air chamber 34 is additionally filled with air. . As a result, the air spring 3 increases its air pressure, overcomes the applied load, expands, and recovers to its set position. In this operation, each wheel operates independently, and as a whole, the vehicle height is raised to the original position to complete the vehicle height adjustment function. In addition, when the load of the vehicle body decreases due to getting off or unloading from the vehicle, the leveling valve 5 discharges the air in the air spring 3 and fills the air even though it is extended by the spring action of the air spring 3. The pressure is reduced and contracted to the set position. Thereby, the air spring 3 can maintain a fixed length, and the height of the vehicle body is maintained by the link mechanism. Since these vehicle height adjustment functions involve filling of air from the air supply source 9 and discharging of air from the air spring 3, the operation becomes relatively slow.

  When a sudden external force is applied to the wheel 1 due to unevenness of the road surface, such as during traveling, the displacement of the wheel 1 due to the force is absorbed by the spring action of the air spring 3, and the influence on the vehicle body can be reduced. In this case, the larger the air capacity of the air spring 3, the smaller the spring constant, and the slower the leveling valve 5 response, the larger the wheel 1 is allowed to displace. The impact can be reduced. Thus, the setting of an appropriate spring constant and responsiveness for improving riding comfort forms the characteristics of an air suspension vehicle.

  Next, an operation during turning of the vehicle such as a curve run will be described. As the vehicle turns, the centrifugal force acts on each part of the vehicle body. The centrifugal force acting on the center of gravity of the vehicle body becomes a force for rolling the vehicle body, and a large load is applied to the outer wheels of the vehicle body that turns as a rolling moment. For example, during the left turn, the right front wheel and rear wheel air springs 3 operate as described with reference to FIG. 2, and the spring constant as an air spring increases. As a result, even with respect to a large rolling moment generated in the vehicle body, the displacement can be reduced, the rolling amount of the vehicle body can be suppressed, and a rolling prevention effect is generated. When the vehicle moves from turning to straight running, the centrifugal force disappears accordingly, the pendulum 29 also returns to the normal position, the communication between the main air chamber 34 and the sub air chamber 35 is restored, and it works as a gentle spring action. Restore comfort. During a right turn, the air springs 3 on the left front wheel and the rear wheel operate to generate a similar rolling prevention effect.

  Next, at the time of sudden braking, an inertial force acts in front of the vehicle, and a large load suddenly acts on the vehicle body. This force acts as a pitching moment that sinks the front of the vehicle body, and applies a load to the suspension mechanism of the front wheels. When the pendulum 29 of the air spring 3 of the front wheel is installed so as to swing forward rather than laterally, the effect of preventing pitching can be obtained by the same action as the effect of preventing rolling. If the pendulum 29 is set in the lateral direction on the rear wheel and in the front direction on the front wheel, the rolling prevention effect can be exerted on the rear wheel and the pitching prevention effect can be exerted on the front wheel. Further, if the pendulum 29 of the front wheel is swung in the lateral direction and the front direction, that is, swung in the direction of about 45 °, it is possible to have both the rolling prevention effect and the pitching prevention effect on the front wheel.

 As described above, according to the air suspension device of the present invention, it is possible to provide an inexpensive and reliable air suspension device that has a rolling prevention effect and a pitching prevention effect together with a comfortable suspension device that improves riding comfort. I can do it.

 In the above description, the double wishbone type suspension device has been described. However, other suspension devices can be easily applied.

Sectional drawing of the air spring which concerns on embodiment of this invention Sectional drawing which shows the action | operation of an air spring when force is acting on the right direction, Partial sectional view showing the operation of the air spring when centrifugal force is acting in the left direction, The system block diagram of the air suspension apparatus which concerns on embodiment of this invention

Explanation of symbols

1 Wheel 2 Lower Arm 3 Air Spring 4 Piping 5 Leveling Valve 6 Swing Lever 7 Sensing Rod 8 Piping 9 Air Supply Source 21 Boot (Housing)
22 Band 23 Upper support (housing)
24 Piston (housing)
25 Ring 26 Plate (partition member)
27 Valve hole (communication hole)
28 Bearing (Pivot member)
29 Pendulum 30 Balancer 31 Valve 32 Pin 33 Center of gravity 34 Main main air chamber 35 Sub air chamber 36 Nipple 37 Rightward centrifugal force 38 Leftward centrifugal force 39 One end of valve hole

Claims (6)

In an air suspension device including an air spring provided between a vehicle body and each wheel and supporting the vehicle body,
The air spring includes a housing that forms an air spring chamber therein, a communication hole that divides the air spring chamber into first and second air spring chambers and communicates with the first and second air spring chambers. A partition member having, a valve that opens and closes the communication hole to communicate or block between the first and second air spring chambers, and switches a spring constant; and a pendulum that operates by acceleration acting on the vehicle body, The air suspension device is characterized in that the valve is configured to mechanically open and close in conjunction with the operation of the pendulum.   The pendulum extends substantially in the vertical direction of the vehicle body in a state where no acceleration acts on the vehicle body, the valve is integrally provided at the upper end of the pendulum, and a balancer for setting a center of gravity position is provided at the lower end of the pendulum. The air suspension device according to claim 1, wherein the air suspension device is provided integrally. 2. The pendulum is pivotally supported by a pivot member fixed to the partition member, and holds the valve in an open state by gravity when acceleration is not applied to the vehicle body. The air suspension device described in 1.   The pendulum is configured to be operated by a lateral acceleration acting on the vehicle body, and the valve closes the communication hole when a predetermined lateral acceleration acts on the pendulum. The air suspension device according to 1.   The pendulum is configured to operate in a forward acceleration acting on the vehicle body, and the valve closes the communication hole when a predetermined forward acceleration acts on the pendulum. The air suspension device according to 1.   The pendulum is configured to operate in lateral and forward acceleration acting on the vehicle body, and the valve closes the communication hole when predetermined lateral acceleration and forward acceleration act on the pendulum. The air suspension device according to claim 1.

Images