JP2018086861A - Air suspension device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To control respective air supply valves, when adjusting a vehicle height, such that vehicle heights on the sides of respective wheels change at the same timing.SOLUTION: A suspension device is provided with: a plurality of air springs 4A-4D interposed between a vehicle body 1 and wheels 2A-2D of a vehicle; a compressor unit 5 for supplying air to the air springs 4A-4D; a plurality of pipes 14A-14D extending from the compressor unit 5 toward the air springs 4A-4D, respectively; a plurality of air supply and exhaust valves 15A-15D provided between the compressor unit 5 and the air springs 4A-4D, respectively; and a controller 18 for controlling opening and closing of the air supply and exhaust valves 15A-15D. The controller 18 causes the air supply and exhaust valves 15A-15D to be opened sequentially from one corresponding to the pipe longer in length among the pipes 14A-14D from the compressor unit 5 to the air springs 4A-4D.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an air suspension device that is mounted on a vehicle such as a four-wheeled vehicle and is preferably used for adjusting the vehicle height.

  In general, as an air suspension apparatus mounted on a vehicle, for example, an air spring provided on each of the left and right front wheels and the left and right rear wheels is used as an on-vehicle air compressor (compressor) serving as a compressed air (compressed air) source. A configuration is known in which the vehicle height is adjusted appropriately according to the time of loading / unloading of luggage, the time of getting on / off of passengers, or other times by expanding and contracting using compressed air discharged from the vehicle.

  Such an air suspension device includes an air compressor, four air springs provided corresponding to front, rear, left, and right wheels, respectively, and the air compressor and each air spring. An air supply valve that is provided and driven by a solenoid, and a controller that controls opening and closing of the air supply valve are provided (for example, see Patent Document 1).

  On the other hand, in Patent Document 2, when there are two or more electric motors with respect to the parking system, each electric motor is started at different timings so that the times when the starting currents of the respective electric motors become maximum do not overlap. Is described.

JP 2010-105584 A JP 2008-213683 A

  By the way, when the installation position of the air compressor is not the center position of the vehicle, for example, the vehicle height adjustment on each wheel side becomes unbalanced as the piping length from the air compressor to each air spring is different. There is a problem of becoming. Further, as the vehicle weight is different between the front wheel side and the rear wheel side (the weight applied to the air spring on the front wheel side is different from the weight applied to the air spring on the rear wheel side), each wheel side (front wheel side and rear wheel side). There is a problem that the vehicle height adjustment on the wheel side becomes unbalanced.

  The present invention has been made in view of the above-described problems of the prior art, and an object of the present invention is to provide an air suspension device that can stably adjust the vehicle height on each wheel side. .

  In order to solve the above-described problems, the present invention provides a plurality of air springs interposed between a vehicle body and wheels of a vehicle, an air supply means for supplying air to the air springs, and an air supply means. A plurality of pipes extending toward the air spring; a plurality of air supply valves provided between the air supply means and the air spring; and a control means for controlling opening and closing of the air supply valve. In the air suspension apparatus, the control means opens the air supply valve in order from the longest pipe from the air supply means to the air spring.

  The present invention also provides a plurality of air springs interposed between a vehicle body and wheels of a vehicle, an air supply means for supplying air to the air spring, and the air supply means toward the air spring. An air suspension device comprising a plurality of extending pipes, a plurality of air supply valves provided between the air supply means and the air spring, and a control means for controlling opening and closing of the air supply valve, The control means is configured to open the air supply valve in order from the heavier vehicle weight of the front wheel side and the rear wheel side.

  According to the present invention, the vehicle height adjustment on each wheel side can be performed stably. That is, when the vehicle height is adjusted, each air supply valve can be controlled so that each wheel stably reaches the target vehicle height.

1 is a conceptual diagram of a vehicle equipped with an air suspension device according to a first embodiment of the present invention. It is a conceptual diagram which shows the air suspension apparatus by the 1st Embodiment of this invention. It is a flowchart which shows the control processing of an air suspension apparatus. It is a flowchart which shows the vehicle height adjustment process in FIG. FIG. 6 is a characteristic diagram showing a change in vehicle height with time of each air suspension and a change in time of each air supply valve in the vehicle height adjustment process. It is a whole block diagram which shows the air suspension apparatus by 2nd Embodiment.

  Hereinafter, an air suspension device according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings, taking as an example the case of mounting on a vehicle such as a four-wheeled vehicle.

  1 to 5 show a first embodiment of the present invention. In FIG. 1, a total of four wheels including left and right front wheels 2A and 2B and left and right rear wheels 2C and 2D are provided on the lower side (road surface side) of the vehicle body 1 constituting the vehicle body. It has been.

  The air suspensions 3A to 3D are provided on the wheels 2A to 2D, respectively. These air suspensions 3A to 3D are provided with air springs 4A to 4D, respectively, interposed between the vehicle body 1 and the wheels 2A to 2D of the vehicle. The air suspensions 3A to 3D adjust the vehicle height of the vehicle body 1 according to the supply and discharge of air.

  And when these compressed air is supplied or discharged | emitted via the below-mentioned piping 14A-14D and supply / exhaust valve 15A-15D, these air springs 4A-4D respond | correspond to the supply / discharge amount (air amount) at this time. It is expanded and contracted up and down. Accordingly, the air springs 4A to 4D individually adjust the vehicle height of the vehicle body 1 together with the air suspensions 3A to 3D, and the vehicle height is raised and lowered for each of the wheels 2A to 2D.

  The in-vehicle compressor unit 5 serving as an air supply means forms a compressed air source that supplies compressed air to the air springs 4A to 4D of the air suspensions 3A to 3D. The compressor unit 5 includes an air compressor 6, an electric motor 7, a suction filter 8, a part of the supply / discharge line 9, an air dryer 10, a slow return valve 11, an exhaust valve 12 and an exhaust line 13, and supply / exhaust valves 15 </ b> A to 15 </ b> D. Is configured to include a valve block 15 integrated with the valve block 15. In this case, for example, a compressor constituted by the air compressor 6 and the electric motor 7 can be used as the air supply means.

  The air compressor 6 is configured by, for example, a reciprocating compressor or a scroll compressor, and is a main part of the compressor unit 5 mounted on the rear side of the vehicle body 1, for example. The air compressor 6 is driven by an electric motor 7 as a drive source, and compresses the outside air or the air sucked from the suction filter 8 side to generate compressed air (air). The suction filter 8 also functions as a silencer that reduces suction noise.

  The supply / exhaust conduit 9 is connected to the discharge side of the air compressor 6. One side (base end side) of the supply / discharge pipe 9 is connected to the discharge side of the air compressor 6 as shown in FIG. 2, and the other side (tip side) extends to the outside of the compressor unit 5. . Connection points 9 </ b> A and 9 </ b> B to which pipes 14 </ b> A to 14 </ b> D to be described later are connected are provided on the distal end side of the supply / exhaust pipe line 9.

  The air dryer 10 constitutes an air drying means provided in the middle of the supply / exhaust conduit 9. The air dryer 10 incorporates, for example, a moisture adsorbent (not shown) or the like, and is disposed between the slow return valve 11 and an exhaust pipe line 13 to be described later. The slow return valve 11 is configured by a parallel circuit of a throttle 11A and a check valve 11B, and the check valve 11B is not opened to reduce the flow rate of the compressed air for the forward flow described later. However, the check valve 11B closes against the flow in the reverse direction, and the flow rate of the compressed air at this time is throttled by the throttle 11A, so that the air dryer 10 slowly reverses with a small flow rate.

  When the high-pressure compressed air generated by the air compressor 6 flows in the forward direction toward the air suspensions 3A to 3D, the air dryer 10 adsorbs moisture by bringing the compressed air into contact with an internal moisture adsorbent. Then, the dried compressed air is supplied toward the air springs 4A to 4D. On the other hand, when the compressed air (exhaust gas) discharged from the air springs 4A to 4D flows through the air dryer 10 in the reverse direction, the dry air flows back through the air dryer 10, so the moisture adsorbent in the air dryer 10 Moisture is desorbed by dry air. Thereby, the moisture adsorbent is regenerated and returned to a state where moisture can be adsorbed again.

  The exhaust valve 12 is connected to the supply / exhaust conduit 9 via the exhaust conduit 13. The exhaust valve 12 includes a solenoid (coil) 12A and is formed as, for example, a 2-port 2-position electromagnetic switching valve (a spring-offset type normally closed valve). The exhaust valve 12 is normally closed to block the exhaust pipe 13 from the exhaust port 13A. When the solenoid 12A of the exhaust valve 12 is excited by energization from the outside (a controller 18 described later), the valve 12 is opened and the exhaust line 13 communicates with the exhaust port 13A, and the compression in the supply / exhaust line 9 is performed. Air is discharged (released) into the atmosphere.

The pipes 14A to 14D extend from the compressor unit 5 toward the air springs 4A to 4D of the air suspensions 3A to 3D, respectively. 2, the lengths of the pipes 14A to 14D, the positions of the air springs 4A to 4D, and the like are shown in FIG. 1 in order to illustrate the air supply / exhaust valves 15A to 15D and the sensors 16A to 16D and 17A to 17D described later. Does not match. These pipes 14A to 14D are arranged to be branched from each other at connection points 9A and 9B from the supply / exhaust pipe 9 in order to individually connect the air springs 4A to 4D to the supply / exhaust pipe 9. Yes. That is, the pipes 14A and 14B are connected to the supply / discharge pipe 9 at the position of the connection point 9A, and the pipes 14C and 14D are connected to the supply / discharge pipe 9 at the position of the connection point 9B. Here, as shown in FIG. 1, the pipe lengths of the pipes 14 </ b> A to 14 </ b> D are formed as L ₁ , L ₂ , L ₃ , and L ₄ , respectively. The relationship represented by

  The supply / exhaust valves 15A to 15D are provided between the compressor unit 5 and the air suspensions 3A to 3D, that is, the pipes 14A to 14D, respectively. In this case, the air supply / exhaust valves 15A to 15D can be provided, for example, closer to the air compressor 6 constituting the air supply means than the air springs 4A to 4D (close to the air compressor 6). These air supply / exhaust valves 15A to 15D are configured as air supply valves. Like the exhaust valve 12, the air supply / exhaust valves 15A to 15D include solenoids 15A1 to 15D1, and are formed as, for example, electromagnetic switching valves with two ports and two positions. Specifically, the supply / exhaust valves 15A to 15D are formed as spring-offset type normally closed valves. In this embodiment, the air supply / exhaust valves 15A to 15D in which the air supply valve and the exhaust valve are integrated will be described. However, the air supply valve and the exhaust valve may be provided separately.

  Here, the solenoids 15A1 to 15D1 are electrically connected to the controller 18. The supply / exhaust valves 15A to 15D are powered by the controller 18 to the solenoids 15A1 to 15D1, thereby attracting (moving) a plunger (not shown) against the spring force and opening the valve. In this valve open state, compressed air can be supplied to or discharged from the air suspensions 3A to 3D. On the other hand, the supply / exhaust valves 15A to 15D can stop the power supply to the solenoids 15A1 to 15D1, thereby closing by the spring force and stopping the supply and discharge of the compressed air to the air suspensions 3A to 3D.

A left front vehicle height sensor 16A is provided on the air suspension 3A on the left front wheel 2A side, and a right front vehicle height sensor 16B is provided on the air suspension 3B on the right front wheel 2B side. A left rear vehicle height sensor 16C is provided on the air suspension 3C on the left rear wheel 2C side, and a right rear vehicle height sensor 16D is provided on the air suspension 3D on the right rear wheel 2D side. These vehicle height sensors 16A to 16D are based on the length of the air springs 4A to 4D in the direction in which the air springs 4A to 4D are expanded or contracted (upward and downward dimensions). High (current vehicle height) h ₁ , h ₂ , h ₃ , and h ₄ are detected, and detection signals are output to the controller 18 described later.

Further, a left front pressure sensor 17A is provided on the air spring 4A on the left front wheel 2A side, and a right front pressure sensor 17B is provided on the air spring 4B on the right front wheel 2B side. The left rear wheel 2C side air spring 4C is provided with a left rear pressure sensor 17C, and the right rear wheel 2D side air spring 4D is provided with a right rear pressure sensor 17D. These pressure sensors 17A to 17D detect the air pressure (pressure) of the compressed air supplied to the air springs 4A to 4D as internal pressures P ₁ , P ₂ , P ₃ , and P ₄ , respectively. Is output to the controller 18.

  The controller 18 is constituted by a microcomputer or the like as control means for controlling opening / closing of the supply / exhaust valves 15A to 15D. As shown in FIG. 2, the input side of the controller 18 is connected to vehicle height sensors 16A to 16D, pressure sensors 17A to 17D, and the output side of the controller 18 includes the electric motor 7, the exhaust valve 12, and the supply / exhaust valve 15A. To 15D solenoids 12A, 15A1 to 15D1, and the like. Here, the controller 18 has a storage unit 18A composed of, for example, a ROM, a RAM, a non-volatile memory, and the like. In this storage unit 18A, for example, a program for air suspension control processing shown in FIG. 3, shown in FIG. A vehicle height adjustment program and the like are stored.

  The controller 18 controls driving and stopping of the air compressor 6 (electric motor 7) based on detection signals input from the vehicle height sensors 16A to 16D, the pressure sensors 17A to 17D, and the duty of the PWM signal, for example. The current supplied to the solenoids 12A and 15A1 to 15D1 of the exhaust valve 12 and the supply / exhaust valves 15A to 15D is controlled by changing the ratio.

  The air suspension apparatus according to the present embodiment has the above-described configuration. Next, air suspension control processing including vehicle height adjustment processing by the controller 18 will be described with reference to FIG.

  First, the controller 18 executes a vehicle height adjustment determination process shown in FIG. 2 when the vehicle engine is started to start and travel. That is, in step 1 in FIG. 2, the controller 18 is initialized, and in the next step 2, it is determined whether or not the control cycle has been reached. The process waits while determining “NO” in step 2, and proceeds to the next step 3 when determining “YES”.

  In step 3, a command signal (current) based on the processing content (calculation result) calculated in the previous control cycle is output to the exhaust valves 12, solenoids 12A and 15A1 to 15D1 of the supply / exhaust valves 15A to 15D, and the electric motor 7. , Drive each actuator. In the next step 4, for example, various signals are output to ports other than the exhaust valve 12 and the supply / exhaust valves 15A to 15D, such as lamps.

  In step 5, a sensor value is input, and detection signals are read from the vehicle height sensors 16A to 16D and the like. Then, in the next step 6, it is determined whether or not the vehicle height adjustment is necessary based on the information read from the vehicle height sensors 16A to 16D and the like. Specifically, the controller 18 performs a vehicle height adjustment process when, for example, a load change when a person gets on and off or a load change when a load is loaded occurs.

  If "YES" is determined in the step 6, it is necessary to adjust the vehicle height. Therefore, the process proceeds to a step 7 and a vehicle height adjusting process described later is performed. On the other hand, when it is determined as “NO” in step 6, it is not necessary to adjust the vehicle height, so that the process proceeds to step 8 to perform control clear processing. Specifically, in order to maintain the current vehicle height, a calculation result for closing the exhaust valve 12 and the air supply / exhaust valves 15A to 15D is output. When Steps 7 and 8 are completed, Step 2 and subsequent steps are repeated.

By the way, when the installation position of the compressor unit 5 is not, for example, the center position of the vehicle, the lengths L ₁ , L ₂ , L ₃ , L _{4 of the} pipes 14A to 14D from the compressor unit 5 to the air springs 4A to 4D. As a result, the vehicle height adjustment on each of the wheels 2A to 2D becomes unbalanced. That is, when the vehicle height adjustment is performed, if the air supply / exhaust valves 15A to 15D for the air springs 4A to 4D corresponding to the wheels 2A to 2D are simultaneously driven, the pipe lengths L ₁ , L ₂ , L ₃ , L ₄ is different, the supply start timing of compressed air to each of the air springs 4A to 4D is shifted. Thereby, the vehicle height adjustment on each of the wheels 2A to 2D may not be performed stably.

In addition, in the case of the configuration in which the supply / exhaust valves 15A to 15D are driven simultaneously, for example, if the vehicle height adjustment is performed near the minimum operating voltage of the battery voltage, the battery voltage is reduced to the minimum operating voltage due to the voltage drop that occurs during valve control. The operation of the supply / exhaust valves 15A to 15D may become unstable. Therefore, in the first embodiment, the controller 18 sequentially increases the lengths L ₁ , L ₂ , L ₃ , and L _{4 of the} pipes 14A to 14D from the compressor unit 5 to the air springs 4A to 4D from the longest. Control (vehicle height adjustment processing) is performed to open the supply / exhaust valves 15A to 15D.

Hereinafter, the vehicle height adjustment process according to the first embodiment will be described with reference to FIG. The vehicle height adjustment process according to the first embodiment will be described by taking as an example a case where the vehicle height is raised from the current vehicle height h ₀ to the target vehicle height h _t of the vehicle.

In step 11, the pressures of the wheels 2A to 2B are measured. That is, the internal pressures P ₁ , P ₂ , P ₃ and P ₄ of the air springs 4A to 4D applied to the wheels 2A to 2D are measured using the pressure sensors 17A to 17D.

In the following step 12, the compressor output flow rate Q _cmp output from the air compressor 6 of the compressor unit 5 is calculated. In this case, for example, a pressure equal to or higher than the highest pressure among the internal pressures P ₁ , P ₂ , P ₃ , P ₄ of the air springs 4A to 4D obtained in step 11 is set as the discharge pressure P _cmp of the air compressor 6, The compressor output flow rate Q _cmp is calculated from the discharge pressure P _cmp and the input voltage v of the air compressor 6 (electric motor 7). The compressor output flow rate Q _cmp is a characteristic function f of the air compressor 6 created in advance using the discharge pressure P _cmp of the air compressor 6 and the input voltage v, for example, as shown in the following equation (2). Calculate using a map.

In step 13, via the pipe 14A~14D calculates the flow rate _{Q 1, Q 2, Q 3} , Q 4 to the air springs 4A~4D wheels 2A-2B. In this case, the flow rate Q flowing through the pipe is generally expressed by the following equation (3). Where K is the flow coefficient, s is the specific gravity of the fluid, L is the pipe length, P _in is the pressure at the pipe inlet (compressor unit 5 side), P _out is the pressure at the pipe outlet (air springs 4A to 4D side), D Is the inner diameter of the pipe.

Here, the relationship between the compressor output flow rate Q _cmp and the flow rate Q ₁₁ when air is supplied only from the air compressor 6 to the air spring 4A is an equal value as expressed by the following equation (4). Become.

The inner diameter D of the respective pipes 14A~14D the same, if the internal pressure _{P 1, P 2, P 3} , P 4 of the air spring 4A~4D was the same, the flow rate Q ₂ of the air spring. 4B, the flow rate Q ₁ And the pipe lengths L ₁ and L _{2 of the} pipes 14A and 14B are expressed by the following equation (5). Similarly, the flow rates Q ₃ and Q ₄ to the air springs 4C and 4D are also expressed by the following formulas 6 and 7 using the flow rate Q ₁ .

The relationship between the compressor output flow rate Q _cmp and the flow rates Q ₁₂ and Q ₂₂ when the air compressor 6 _supplies air only to the air springs 4A and 4B is expressed by the following equation (8).

Accordingly, the flow rates Q ₁₂ and Q ₂₂ flowing through the pipes 14A and 14B are expressed by the following formulas 9 and 10 using the compressor output flow rate Q _cmp and the pipe lengths L ₁ and L _{2 of the} pipes 14A and 14B. Is done.

On the other hand, the relationship between the compressor output flow rate Q _cmp and the flow rates Q ₁₃ , Q ₂₃ , Q ₃₃ when supplying air only from the air compressor 6 to the air springs 4A, 4B, 4C is expressed by the following equation (11). expressed.

Accordingly, the flow rates Q ₁₃ , Q ₂₃ , and Q ₃₃ flowing through the pipes 14A, 14B, and 14C are as follows using the compressor output flow rate Q _cmp and the pipe lengths L ₁ , L ₂ , and L _{3 of the} pipes 14A, 14B, and 14C. It is expressed by the following equation (12), equation (13), and equation (14).

Furthermore, the relationship between the compressor output flow rate Q _cmp and the flow rates Q ₁₄ , Q ₂₄ , Q ₃₄ , Q ₄₄ when the air compressor 6 _supplies air to the air springs 4A, 4B, 4C, 4D is as follows. It is expressed by equation (15).

Accordingly, the flow rates Q ₁₄ , Q ₂₄ , Q ₃₄ , and Q ₄₄ flowing through the pipes 14A, 14B, 14C, and 14D are the compressor output flow rate Q _cmp and the pipe lengths L ₁ , L ₂ , Using L ₃ and L ₄ , the following Expression 16, Expression 17, Expression 18, and Expression 19 are used.

Next, in step 14, when performing vehicle height adjustment processing, the air volumes V _1input , V _2input , V _3input and V _4input necessary for the air springs 4A to 4D of the wheels 2A to _2D are calculated. Here, when the vehicle height adjustment process is performed on the air spring 4A, the volume V _1input is expressed by the following equation (20). However, P ₁ is the internal pressure of the air springs 4A, S ₁ is the cross-sectional area of the air spring 4A, h _t the target vehicle height, h ₁ is the current vehicle height of the air suspension 3A, P _atm is the atmospheric pressure.

Further, the air volumes V _2input , V _3input , and V _4input necessary for the air springs 4B, 4C, and 4D are also expressed in the same manner as the above equation (20). In this case, the internal pressure P ₁ , the cross-sectional area S ₁ and the current vehicle height h ₁ are the internal pressures P ₂ , P ₃ and P ₄ of the air springs 4B, 4C and 4D, the cross-sectional areas S ₂ , S ₃ and S ₄ and the current vehicle. The heights h ₂ , h ₃ and h ₄ are used, respectively.

In step 15, when performing vehicle height adjustment processing (supply time corresponding to the pipe length) supply sequence required for air springs 4A~4D wheel _{2A~2D t 1, t 2, t} 3 , T ₄ is calculated. In this case, to start the air supply in the order of the air spring 4A - 4D, air suspension 3A~3D is (at the same timing) at the same time the target vehicle height h _t and calculates the supply time t ₁ ~t ₄ to reach. That is, the air supply times t _{1 to} t ₄ are _calculated by using the flow rates Q _{1 to} Q ₄ and the volumes V _{1input to} V _4input obtained in steps 13 and 14, _respectively , It is expressed by the following equation (24)

Next, the vehicle height adjustment process in the first embodiment will be described with reference to FIG. 5 together with the opening / closing control of the air supply / exhaust valves 15A to 15D. In this case, the vehicle heights h ₁ , h ₂ , h ₃ and h ₄ of the air suspensions 3A to 3D are the same at the current vehicle height h ₀ , and the vehicle heights h ₁ , h ₂ , h ₃ and h ₄ are set as the target vehicles. the case raised to a high h _t be described as an example.

  First, the controller 18 opens the supply / exhaust valves 15A to 15D in order from the longer pipes 14A to 14D from the compressor unit 5 to the air springs 4A to 4D. In this case, the controller 18 opens and closes the supply / exhaust valves 15A, 15B (or supply / exhaust valves 15C, 15D) of the front wheels 2A, 2B (or rear wheels 2C, 2D) adjacent to each other in the left and right directions among the wheels 2A-2D. Different timings. Further, the controller 18 varies the opening / closing timing of the supply / exhaust valves 15A, 15B, 15C, 15D of the front wheels 2A, 2B and the rear wheels 2C, 2D adjacent to each other in the front and rear directions among the wheels 2A-2D. That is, in the first embodiment, the opening / closing timings of the supply / exhaust valves 15A, 15B, 15C, 15D of the four wheels (all wheels 2A to 2D) are made different.

Specifically, the controller 18 opens the first intake and exhaust valve 15A of the pipe 14A having the longest pipe length L ₁ among the pipes 14A-14D, to supply compressed air to the air springs 4A. In this case, since the air compressor 6 has the air supply only to the air springs 4A, the flow rate to Q ₁ to the air spring. 4A flow Q _11, and the air supply time becomes t ₁ (Eq. 4, the number 24 formula reference).

Next, the controller 18 opens the air supply / exhaust valve 15B of the pipe 14B having the _second longest pipe length L2 among the pipes 14A to 14D, and supplies compressed air to the air spring 4B. In this case, since air is supplied only from the air compressor 6 to the air springs 4A and 4B, the flow rates Q ₁ and Q ₂ to the air springs 4A and 4B are the flow rates Q ₁₂ and Q ₂₂ , and the air supply time is t _2. (See Equation 9, Equation 10, Equation 23).

Next, the controller 18 opens the air supply / exhaust valve 15C of the pipe 14C having the _third longest pipe length L3 among the pipes 14A to 14D, and supplies compressed air to the air spring 4C. In this case, since air is supplied only from the air compressor 6 to the air springs 4A, 4B, 4C, the flow rates Q ₁ , Q ₂ , Q ₃ to the air springs 4A, 4B, 4C are flow rates Q ₁₃ , Q ₂₃ , next Q _33, the air supply time is t ₃ (equation (12) to several 14 formula, reference number 22 formula).

Then, the controller 18 opens the air supply / exhaust valve 15D of the pipe 14D having the _fourth longest pipe length L4 among the pipes 14A to 14D, and supplies compressed air to the air spring 4D. In this case, the air spring 4A from the air compressor 6, 4B, 4C, since the air supply to 4D, the flow rate to Q ₁ air springs 4A, 4B, 4C, the _{4D, Q 2, Q 3,} Q 4 are flow Q ₁₄ , Q ₂₄ , Q ₃₄ , and Q ₄₄ , and the air supply time is t ₄ (see Formula 16 to Formula 19 and Formula 21).

Finally, controller 18, when the height h ₁ of the air suspension _{3A~3D, h 2, h 3,} h 4 reaches the target vehicle height h _t respectively, close the solenoid 15A1~15D1 of intake and exhaust valves 15A~15D To finish the vehicle height adjustment process. Even when the vehicle height in the vehicle height adjustment process is lowered, the supply / exhaust valves 15A to 15D can be opened in order from the longer piping 14A to 14D, and the compressed air can be discharged to the outside.

Thus, according to the air suspension apparatus of the first embodiment, the controller 18 opens the supply / exhaust valves 15A to 15D in order from the longer pipes 14A to 14D from the compressor unit 5 to the air springs 4A to 4D, The vehicle height adjustment process is performed. In this case, the flow rates Q ₁ , Q ₂ , Q ₃ , and Q ₄ to the air springs 4A to 4D are set in consideration of the pipe lengths L ₁ , L ₂ , L ₃ , and L ₄ of the pipes 14A to 14D. Calculated. Thereby, when performing vehicle height adjustment, since it controls based on the control sequence calculated beforehand, the influence by road surface input etc. can be reduced and the unnecessary inclination (hunting etc.) of the vehicle body 1 can be suppressed.

In consideration of the piping pipe length L ₁ of _{14A~14D, L 2, L 3,} L 4, air suspension 3A~3D wheel 2A~2D simultaneously to the target vehicle height h _t (at the same timing) arrives The vehicle height adjustment processing is performed. Thereby, the raising and lowering of the vehicle height can be made uniform by the wheels 2A to 2B, and the vehicle body 1 can be raised and lowered in a form close to the horizontal. As a result, an unnecessary inclination of the vehicle body 1 can be suppressed, so that the balance between the luggage and the occupant is not lost and the riding comfort can be improved.

  Further, the supply / exhaust valves 15A to 15D include solenoids 15A1 to 15D1, and the controller 18 controls the adjacent wheels 2A to 2D (adjacent front wheels 2A and 2B, adjacent rear wheels 2C and 2D, adjacent front wheels 2A and 2B and the rear. The opening / closing timings of the supply / exhaust valves 15A, 15B of the wheels 2C, 2D) are made different. Thereby, the timing of the starting current supplied to the solenoids 15A1 to 15D1 can be shifted. As a result, since a large current does not flow from the battery or the like to the solenoids 15A1 to 15D1 at the same time and a large voltage drop can be suppressed, the burden on the battery can be reduced.

  Next, FIG. 6 shows a second embodiment of the present invention. The feature of the second embodiment resides in that the air suspension device is configured as a closed type. In the second embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  In FIG. 6, a compressor 21 as an air supply means compresses air and supplies compressed air to the air springs 4A and 4B (4C and 4D) of the air suspensions 3A and 3B (3C and 3D). The compressor 21 also has a function of sending (pulling) the compressed air of the air springs 4A, 4B (4C, 4D) into the tank 22 when exhausting the compressed air from the air springs 4A, 4B (4C, 4D). doing. Here, the compressor 21 includes an air compressor 21A and an electric motor 21B that drives the air compressor 21A. A suction filter 8 is provided on the suction port 21C side of the compressor 21 to remove dust and the like in the outside air sucked into the air compressor 21A. On the other hand, a replenishment passage 23 to be described later is connected to the discharge port 21 </ b> D of the compressor 21.

  The tank 22 stores air compressed by the compressor 21 (compressed air). The discharge port 21 </ b> D of the compressor 21 and the tank 22 are connected via a supply passage 23, and the compressed air discharged from the compressor 21 is stored in the tank 22 through the supply passage 23. The compressed air stored in the tank 22 is supplied to the air springs 4A and 4B of the air suspensions 3A and 3B through a supply / discharge passage 25 described later.

  The first check valve (check valve) 24 is located between the tank 22 and the air dryer 10 and is provided in the middle of the supply passage 23. The first check valve 24 allows a flow of compressed air from the compressor 21 toward the tank 22 and prevents a reverse flow.

  The supply / discharge passage 25 connects between the tank 22 and the air springs 4A and 4B of the air suspensions 3A and 3B. The supply / discharge passage 25 constitutes a pipe through which compressed air supplied from the tank 22 to the air suspensions 3A and 3B flows and air discharged from the air suspensions 3A and 3B flows. Here, the supply / discharge passage 25 branches into two branch supply / discharge passages 25A, 25B between a supply / discharge switching valve 26 and air suspensions 3A, 3B, which will be described later, and one branch supply / discharge passage 25A is an air suspension. The other branch supply / discharge passage 25B is connected to the air spring 4B of the air suspension 3B.

  The supply / exhaust switching valve 26 is provided in the middle of the supply / exhaust passage 25, and the supply / exhaust switching valve 26 is constituted by an electromagnetic valve at a 3-port 2-position. Here, the supply / discharge switching valve 26 selectively switches between a supply position (a) for supplying compressed air to the air suspensions 3A and 3B and a discharge position (b) for discharging the air in the air suspensions 3A and 3B. It is done. The supply / discharge switching valve 26 is controlled by the current supplied by a controller (not shown). For example, when the solenoid 26A is not excited, the spring 26B holds the discharge position (b), and the solenoid 26A is excited. When it is done, it is switched to the supply position (a) against the spring 26B.

  The supply / exhaust valve 27 is located between the air suspension 3 </ b> A and the supply / discharge switching valve 26 and is provided in the middle of the branch supply / discharge passage 25 </ b> A. The air supply / exhaust valve 27 is a 2-port 2-position electromagnetic valve as an air supply valve. The supply / exhaust valve 27 opens the branch supply / exhaust passage 25A to allow air supply / discharge to / from the air spring 4A of the air suspension 3A, and closes the branch supply / discharge passage 25A to close the air spring 4A of the air suspension 3A. Is selectively switched to a closed position (b) for shutting off air supply / exhaust to control the expansion and contraction of the air suspension 3A. Here, the supply / exhaust valve 27 holds the closed position (b) for closing the branch supply / exhaust passage 25B by the spring 27B when the solenoid 27A is not excited by the controller, for example, and when the solenoid 27A is excited, the spring 27B It is switched to the open position (a) that opens the branch supply / discharge passage 25A against 27B.

  The supply / exhaust valve 28 is located between the air suspension 3B and the supply / discharge switching valve 26 and is provided in the middle of the branch supply / discharge passage 25B. This air supply / exhaust valve 28 is constituted by a 2-port 2-position electromagnetic valve as an air supply valve, like the air supply / exhaust valve 27, and closes the open / close position (a) for opening the branch supply / discharge passage 25B and the branch supply / discharge passage 25B. By selectively switching to the closed position (b), the expansion and contraction of the air suspension 3B are controlled. Here, when the solenoid 28A is not excited, for example, the supply / exhaust valve 28 holds the closed position (b) for closing the branch supply / exhaust passage 25B by the spring 28B, and when the solenoid 28A is excited, the spring 28B It is switched to the open position (a) that opens the branch supply / discharge passage 25B against 28B.

  The return passage 29 connects between the supply / discharge switching valve 26 and the discharge port 21 </ b> D of the compressor 21. The return passage 29 is configured so that when the supply / discharge switching valve 26 holds the discharge position (b) and the supply / exhaust valves 27, 28 are switched to the open position (a), the air springs 4A, 4A of the air suspensions 3A, 3B. The air discharged from 4B is returned to the suction side (suction port 21C side) of the compressor 21.

  The return passage opening / closing valve 30 is provided in the middle of the return passage 29, and the return passage opening / closing valve 30 is constituted by a 2-port 2-position electromagnetic valve, and opens and closes the return passage 29. Here, the return passage opening / closing valve 30 has an open position (a) for opening the return passage 29 and a closed position (b) for closing the return passage 29. For example, when the solenoid 30A is not excited, the return passage opening / closing valve 30 holds the closed position (b) by the spring 30B, and when the solenoid 30A is excited, the return passage opening / closing valve 30 is opened against the spring 30B ( a).

  The second check valve 31 is provided on the suction side of the compressor 21. The second check valve 31 is disposed between the suction port 21 </ b> C of the compressor 21 and the suction filter 8. The second check valve 31 allows the flow of air from the suction filter 8 toward the compressor 21 and blocks the reverse flow.

  The bypass passage 32 is provided between the supply passage 23 and the return passage 29. Here, one end side of the bypass passage 32 is connected in the middle of the return passage 29 at a connection portion 32A located between the supply / discharge switching valve 26 and the return passage opening / closing valve 30, and the other end side of the bypass passage 32 is A connection portion 32 </ b> B located between the air dryer 10 and the first check valve 24 is connected in the middle of the supply passage 23. The bypass passage 32 is for releasing the air in the air springs 4A and 4B of the air suspensions 3A and 3B into the atmosphere by bypassing the compressor 21.

  The third check valve 33 is provided in the middle of the bypass passage 32, and the third check valve 33 allows air flow from the return passage 29 toward the supply passage 23 and prevents reverse flow. is there.

  The exhaust passage 34 discharges air in the air springs 4A and 4B of the air suspensions 3A and 3B to the atmosphere. Here, one end side of the exhaust passage 34 is connected to the supply passage 23 at a connection portion 34 </ b> A located between the discharge port 21 </ b> D of the compressor 21 and the air dryer 10. Further, the other end side of the exhaust passage 34 is opened to the atmosphere via the suction filter 8. The exhaust passage 34 allows the air discharged from the air suspensions 3 </ b> A and 3 </ b> B to be released into the atmosphere without being introduced into the tank 22.

  The exhaust passage opening / closing valve 35 is provided in the middle of the exhaust passage 34, and the exhaust passage opening / closing valve 35 is constituted by a 2-port 2-position electromagnetic valve, and opens and closes the exhaust passage 34. Here, the exhaust passage opening / closing valve 35 has an open position (a) for opening the exhaust passage 34 and a closed position (b) for closing the exhaust passage 34. For example, when the solenoid 35A is not excited, the exhaust passage opening / closing valve 35 holds the closed position (b) by the spring 35B, and when the solenoid 35A is excited, the exhaust passage opening / closing valve 35 is opened against the spring 35B. a).

  The air suspension device according to the second embodiment has the above-described configuration. Next, vehicle height adjustment processing according to the second embodiment will be described. Also in this case, as in the first embodiment, the controller opens the supply / exhaust valves 27 and 28 in order from the longer branch supply / discharge passages 25A and 25B as piping from the compressor 21 to the air springs 4A and 4B. Car height adjustment processing.

  Thus, according to the second embodiment, it is possible to obtain substantially the same operational effects as those of the first embodiment. In the second embodiment, when the vehicle height is raised by the air suspensions 3A, 3B, the compressed air stored in the tank 22 in advance is supplied to the air springs 4A, 4B of the air suspensions 3A, 3B through the supply / discharge passage 25. It is configured to do. Thereby, compared with the case where the air compressed by the compressor 21 is supplied directly to the air suspensions 3A and 3B, for example, the compressed air can be supplied quickly, and the vehicle height can be raised quickly.

  In the first embodiment, in the vehicle height adjustment process, the controller 18 opens the supply / exhaust valves 15A to 15D in order from the longer piping 14A to 14D from the compressor unit 5 to the air springs 4A to 4D. It was set as the structure to do. However, the present invention is not limited to this, and the controller (control means) opens the air supply / exhaust valves (air supply valves) in order from the heaviest vehicle weight (weight) of the front wheel side and the rear wheel side of the vehicle body. It is good also as composition to do. That is, as the vehicle weight differs between the front wheel side and the rear wheel side (the weight applied to the air spring on the front wheel side is different from the weight applied to the air spring on the rear wheel side), each wheel side (front wheel side and rear wheel side). There is a problem that the vehicle height adjustment on the wheel side becomes unbalanced. Therefore, the control means opens the air supply / exhaust valves (air supply valves) in order from the heavier vehicle weight (weight) of the front wheel side and the rear wheel side of the vehicle body. Also in this case, the vehicle height adjustment on each wheel side can be performed stably. The same applies to the second embodiment.

  Furthermore, when raising the vehicle height in the vehicle height adjustment process, the controller (control means) opens the air supply / exhaust valve (air supply valve) in order from the rear wheel side of the front wheel side and the rear wheel side of the vehicle body. It is good also as a structure. That is, when the air supply / exhaust valve (air supply valve) is opened in order from the rear wheel side of the front wheel side and the rear wheel side of the vehicle body, the front wheel side of the vehicle body rises earlier than the rear wheel side, and the light of the vehicle The shaft (light) may face upward. Therefore, the control means opens the air supply / exhaust valve (air supply valve) in order from the rear wheel side of the front wheel side and the rear wheel side of the vehicle body. Thereby, since it can avoid that the front-wheel side of a vehicle body raises with respect to a rear-wheel side, it can suppress that the optical axis (light) of a vehicle faces upwards. At this time, in the case of lowering the vehicle height, the controller may be configured to open the air supply / exhaust valves in order from the front wheel side and discharge air. The same applies to the second embodiment.

  In the first embodiment, the controller 18 is configured to vary the opening / closing timings of the supply / exhaust valves 15A, 15B, 15C, 15D of all four wheels. However, the present invention is not limited to this, depending on the length of the piping of each air spring from the air supply means and / or depending on the weight applied to each air spring, the front-rear direction, the left-right direction, The opening / closing timings of the air supply valves of the wheels adjacent in at least one of the diagonal directions can be made different. That is, for example, the controller may be configured to vary the opening / closing timings of the air supply valves of the front wheels (or rear wheels D) adjacent in the left and right directions. Moreover, it is good also as a structure which makes the opening-and-closing timing of the air supply valve | bulb of the wheel adjacent to the front and back direction differ. Furthermore, it is good also as a structure which makes the opening-and-closing timing of the air supply valve of the wheel of a diagonal direction differ. The same applies to the second embodiment.

  In the first embodiment, the air suspension device controls the four air suspensions 3A to 3D provided to correspond to the front, rear, left, and right wheels 2A to 2D, respectively. It was set as the structure which adjusts. However, the present invention is not limited to this, and the vehicle height may be adjusted by providing the air suspension only on the front wheel, or the vehicle height may be adjusted by providing the air suspension only on the rear wheel. In this case, the control means can vary the opening / closing timings of the air supply valves of the front wheels (or rear wheels) adjacent in the left and right directions. The same applies to the second embodiment.

  Moreover, in the said 1st form, as shown in FIG. 1, the structure which provides the compressor unit 5 in the center side of the vehicle body 1 was mentioned as an example, and was demonstrated. However, the present invention is not limited to this, and the compressor unit may be provided, for example, on the front side or the rear side of the vehicle. Similarly, the left and right directions may be provided on the left side of the vehicle or on the right side. The same applies to the second embodiment.

  In the first embodiment, the controller 18 opens the supply / exhaust valves 15A to 15D in order from the longer pipes 14A to 14D from the compressor unit 5 (air supply means) to the air springs 4A to 4D. did. However, the present invention is not limited to this, and the controller may be configured to open the air supply / exhaust valves in order from the longer piping from the air supply / exhaust valve (air supply valve) to the air spring. The same applies to the second embodiment.

  Further, in the first and second embodiments, the case where the air suspension device of the present invention is applied to a vehicle of a four-wheel automobile has been described as an example. However, the present invention is not limited thereto, and for example, a railcar or the like. You may apply to other vehicles like.

  In the present embodiment, the air supply / exhaust valves 15A to 15D in which the air supply valve and the exhaust valve are integrated have been described. However, the air supply valve and the exhaust valve may be provided separately.

  In addition, the supply and exhaust valves 15A to 15D are opened at the time of supply and exhaust in order from the longer pipes 14A to 14D from the compressor unit 5 to the air springs 4A to 4D. However, the technology of the present invention may be implemented only when supplying air or only when exhausting.

  In the present embodiment, the supply / exhaust valves 15A to 15D are integrated to configure the valve block 15, but may be provided.

  Next, the invention included in the above embodiment will be described. According to the present invention, the air supply valve is configured using a solenoid, and the control means is configured to vary the opening / closing timing of the air supply valve of at least adjacent wheels among the wheels. Thereby, the vehicle height adjustment on each wheel side can be stably performed (for example, the timing to reach the target height is almost simultaneously). Moreover, the voltage drop amount of the battery voltage due to the inrush current can be reduced.

  According to the present invention, the control means is configured to open the air supply valve in order from the heavier vehicle weight of the front wheel side and the rear wheel side. This also has the same effect as the case described above.

  Further, according to the present invention, the control means is configured to open the air supply valve in order from the rear wheel side of the front wheel side and the rear wheel side. In this case, it can suppress that the optical axis (light) of a vehicle faces upwards. Moreover, the voltage drop amount of the battery voltage due to the inrush current can be reduced.

1 Car body 2A, 2B Front wheel
2C, 2D Rear wheel (wheel)
4A to 4D Air spring 5 Compressor unit (air supply means)
14A-14D, 25, 25A, 25B Piping 15A-15D, 27, 28 Supply / exhaust valve (supply valve)
15A1-15D1, 27A, 28A Solenoid 18 Controller (control means)
21 Compressor (air supply means)

Claims (4)

A plurality of air springs interposed between the vehicle body and the wheels;
An air supply means for supplying air to the air spring;
A plurality of pipes respectively extending from the air supply means toward the air spring;
A plurality of air supply valves respectively provided between the air supply means and the air spring;
Control means for controlling opening and closing of the air supply valve;
An air suspension device comprising:
The air suspension device according to claim 1, wherein the control means opens the air supply valve in order from the longest pipe from the air supply means to the air spring. The air supply valve is configured using a solenoid,
2. The air suspension device according to claim 1, wherein the control unit varies opening / closing timings of the air supply valve of at least adjacent wheels among the wheels. A plurality of air springs interposed between the vehicle body and the wheels;
An air supply means for supplying air to the air spring;
A plurality of pipes respectively extending from the air supply means toward the air spring;
A plurality of air supply valves respectively provided between the air supply means and the air spring;
Control means for controlling opening and closing of the air supply valve;
An air suspension device comprising:
The air suspension device according to claim 1, wherein the control means opens the air supply valve in order from the heavier vehicle weight of the front wheel side and the rear wheel side. A plurality of air springs interposed between the vehicle body and the wheels;
An air supply means for supplying air to the air spring;
A plurality of pipes respectively extending from the air supply means toward the air spring;
A plurality of air supply valves respectively provided between the air supply means and the air spring;
Control means for controlling opening and closing of the air supply valve;
An air suspension device comprising:
The air suspension apparatus, wherein the control means opens the air supply valve in order from the rear wheel side of the front wheel side and the rear wheel side.

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