Oil-gas shock absorber, oil-gas suspension system and vehicle

Abstract

The present invention relates to the technical field of vibration damping devices, and particularly relates to an oil-gas vibration damping device, an oil-gas suspension system and a vehicle. One end of the oil-gas vibration damping device is connected to a vehicle frame, and the other end is connected to an axle. The oil-gas vibration damping device defines a first chamber for accommodating gas and a second chamber for accommodating liquid. The volume of the gas in the first chamber is inversely related to the value of the axial pressure load received by the oil-gas vibration damping device, and the length of the oil-gas vibration damping device is directly related to the volume of the liquid in the second chamber. The oil-gas vibration damping device and the oil-gas suspension system applying the oil-gas vibration damping device improve the driving safety of the vehicle.

Description

Technical Field

[0001] The present invention relates to a vibration damping device, and more particularly to a hydropneumatic vibration damping device, a hydropneumatic suspension system and a vehicle. Background Art

[0002] Heavy-duty engineering vehicles operate under harsh conditions. The road surface is uneven and bumpy with large undulations. In severe cases, the transport vehicle may lose balance, components may be damaged, and even mechanical and personal accidents may occur. Therefore, engineering vehicles must be equipped with a buffer and vibration damping device.

[0003] In some existing heavy-duty engineering vehicles, leaf springs are used as elastic vibration damping elements connecting the axle and the vehicle frame. However, there are also some problems, such as Figure 1 As shown, when there is an uneven load (i.e., the weight of the cargo is unevenly distributed in the width direction of the vehicle), the force exerted by the cargo on the vehicle frame is uneven in the width direction of the vehicle. On the side where the cargo is heavier ( Figure 1 the left side in the leaf spring on that side is subjected to a greater pressure and has a correspondingly larger deformation. The vehicle frame tilts towards that side, causing the cargo to further slide towards that side, resulting in additional roll. In severe cases, it may even cause the vehicle to overturn.

[0004] In view of the above-mentioned prior art, the present invention provides a hydropneumatic vibration damping device, a hydropneumatic suspension system and a vehicle to solve the above technical problems.

[0005] One aspect of an embodiment of the present invention provides a hydropneumatic vibration damping device, one end of which is connected to the vehicle frame and the other end is connected to the axle; the hydropneumatic vibration damping device defines a first chamber for accommodating gas and a second chamber for accommodating liquid; the volume of the gas in the first chamber is inversely related to the value of the axial pressure load received by the hydropneumatic vibration damping device, and the length of the hydropneumatic vibration damping device is directly related to the volume of the liquid in the second chamber.

[0006] One aspect of an embodiment of the present invention provides a hydropneumatic suspension system, comprising:

[0007] Hydropneumatic vibration damping devices provided on both sides in the width direction of the vehicle, one end of each hydropneumatic vibration damping device is connected to the vehicle frame and the other end is connected to the axle; the hydropneumatic vibration damping device defines a first chamber for accommodating gas and a second chamber for accommodating liquid; the volume of the gas in the first chamber is inversely related to the value of the axial pressure load received by the hydropneumatic vibration damping device, and the length of the hydropneumatic vibration damping device is directly related to the volume of the liquid in the second chamber,

[0008] A pressure source configured to supply pressurized liquid to the second chamber;

[0009] A liquid storage container configured to receive liquid from the second chamber;

[0010] A load sensing valve group, fluidly connected to the oil-gas shock absorber device; the load sensing valve group is configured to fluidly connect one of the pressure source and the liquid storage container to the second chamber;

[0011] Wherein, on at least one side in the vehicle width direction, when the distance between the axle and the vehicle frame is less than a preset distance, liquid is supplemented from the pressure source into the second chamber of the oil-gas shock absorber device on this side; when the distance between the axle and the vehicle frame is greater than the preset distance, liquid is discharged from the oil-gas shock absorber device on this side to the liquid storage container.

[0012] As a preferred embodiment, the load sensing valve group has a closed state in which the second chamber is closed, a refueling state in which the pressure source is communicated with the second chamber, and an oil discharging state in which the liquid storage container is communicated with the second chamber.

[0013] As a preferred embodiment, the load sensing valve group has a balance valve, the balance valve has a balance valve inlet pipeline communicated with the pressure source, a balance valve outlet pipeline communicated with the liquid storage container, and a working port pipeline communicated with the second chamber;

[0014] In the refueling state, the balance valve inlet pipeline is communicated with the working port pipeline,

[0015] In the oil discharging state, the balance valve outlet pipeline is communicated with the working port pipeline;

[0016] In the closed state, the balance valve inlet pipeline, the balance valve outlet pipeline and the working port pipeline are all closed.

[0017] As a preferred embodiment, the load sensing valve group has a balance valve,

[0018] The load sensing valve group is fixed to the vehicle frame, and the valve core of the balance valve is elastically and detachably connected to the axle.

[0019] As a preferred embodiment, the load sensing valve group further includes a damping unit, the damping unit defines a first chamber and a second chamber, and the first chamber and the second chamber are configured to have a flow-limiting communication path;

[0020] There is a piston between the first chamber and the second chamber, and the piston is connected to the valve core of the balance valve.

[0021] As a preferred embodiment, in the damping unit, a return spring for pushing the valve core to move downward when the valve core of the balance valve is separated from the axle is provided in the first chamber.

[0022] As a preferred embodiment, the load sensing valve group includes a feedback rod, one end of the feedback rod is connected to the spool of the balance valve, and the other end abuts against an elastic element fixed on the axle;

[0023] The elastic force of the elastic element is greater than the elastic force of the return spring.

[0024] As a preferred embodiment, the elastic element is an elastic reed,

[0025] When two adjacent axles are in the front - rear direction of the vehicle, both ends of the elastic reed are respectively connected to the front axle and the rear axle; the lower end of the feedback rod abuts against the middle part of the elastic reed.

[0026] As a preferred embodiment, the pressure source further includes an accumulator fluidly connected to the load sensing valve group for supplying pressurized liquid to the load sensing valve group.

[0027] Another aspect of the present invention provides a hydro - pneumatic suspension system, having:

[0028] Hydro - pneumatic shock absorbers provided on both sides in the vehicle width direction, one end of the hydro - pneumatic shock absorber is connected to the vehicle frame, and the other end is connected to the axle; the hydro - pneumatic shock absorber defines a first chamber for accommodating gas and a second chamber for accommodating liquid; the volume of the gas in the first chamber is inversely related to the axial pressure load value received by the hydro - pneumatic shock absorber, and the length of the hydro - pneumatic shock absorber is directly related to the volume of the liquid in the second chamber;

[0029] A pressure source configured to be able to supply pressurized liquid to the second chamber;

[0030] A liquid storage container configured to be able to receive liquid from the second chamber;

[0031] Two load sensing valve groups respectively corresponding to and fluidly connected to the hydro - pneumatic shock absorber on one side in the vehicle width direction, the load sensing valve group being configured to be able to fluidly connect one of the pressure source and the liquid storage container to the second chamber;

[0032] An inclination sensor, connected to the vehicle frame, for detecting the inclination angle of the vehicle frame in the vehicle width direction and sending an inclination angle signal to the controller;

[0033] A controller, which is respectively signal-connected to the tilt sensor and the load-sensing valve group, is configured to be able to receive the tilt angle signal, judge the tilt condition of the vehicle frame in the vehicle width direction according to the tilt angle signal, and control the load-sensing valve group on the lower side in the vehicle width direction to supplement liquid into the second chamber of the corresponding oil-gas shock absorber, and / or control the load-sensing valve group on the higher side in the vehicle width direction to discharge part of the liquid in the second chamber of the corresponding oil-gas shock absorber to the liquid storage container.

[0034] Another aspect of the present invention provides a vehicle, including:

[0035] Axles, with wheels respectively provided at both ends of the axles;

[0036] A vehicle frame, located above the axles;

[0037] Oil-gas shock absorbers provided on both sides in the vehicle width direction, one end of the oil-gas shock absorber is connected to the vehicle frame, and the other end is connected to the axles; the oil-gas shock absorber defines a first chamber for containing gas and a second chamber for containing liquid; when the oil-gas shock absorber is subjected to an axial pressure, it shortens due to the compression of the volume of the gas in the first chamber, and the length of the oil-gas shock absorber is positively correlated with the volume of the liquid in the second chamber,

[0038] A pressure source, which is configured to supply pressurized liquid to the second chamber;

[0039] A liquid storage container, which is configured to receive liquid from the second chamber;

[0040] A load-sensing valve group, which is fluidly connected to the oil-gas shock absorber; the load-sensing valve group is configured to fluidly connect one of the pressure source and the liquid storage container to the second chamber;

[0041] Wherein, on at least one side in the vehicle width direction, when the distance between the axle and the vehicle frame is less than a preset distance, liquid is supplemented into the second chamber of the oil-gas shock absorber on this side from the pressure source; when the distance between the axle and the vehicle frame is greater than the preset distance, liquid is discharged from the oil-gas shock absorber on this side to the liquid storage container.

[0042] Another aspect of the present invention provides a vehicle, including:

[0043] Axles, with wheels respectively provided at both ends of the axles;

[0044] A vehicle frame, located above the axles;

[0045] An oil-gas shock absorber device provided on both sides in the vehicle width direction, one end of the oil-gas shock absorber device is connected to the vehicle frame, and the other end is connected to the axle; the oil-gas shock absorber device defines a first chamber for accommodating gas and a second chamber for accommodating liquid; the volume of the gas in the first chamber is inversely related to the axial pressure load value received by the oil-gas shock absorber device, and the length of the oil-gas shock absorber device is directly related to the volume of the liquid in the second chamber;

[0046] A pressure source configured to supply pressurized liquid to the second chamber;

[0047] A liquid storage container configured to receive liquid from the second chamber;

[0048] Two load sensing valve groups respectively corresponding to and fluidly connected to the oil-gas shock absorber device on one side in the vehicle width direction; the load sensing valve groups are configured to fluidly connect one of the pressure source and the liquid storage container to the second chamber;

[0049] An inclination sensor, connected to the vehicle frame, for detecting the inclination angle of the vehicle frame in the vehicle width direction and sending an inclination angle signal to the controller;

[0050] A controller, respectively signal-connected to the inclination sensor and the load sensing valve groups, the controller is configured to be able to receive the inclination angle signal, judge the inclination condition of the vehicle frame in the vehicle width direction according to the inclination angle signal, and control the load sensing valve group on the lower side in the vehicle width direction to supplement liquid into the second chamber of the corresponding oil-gas shock absorber device, and / or control the load sensing valve group on the higher side in the vehicle width direction to discharge the liquid in the second chamber of the corresponding oil-gas shock absorber device to the liquid storage container.

[0051] According to the present invention, by dynamically adjusting the length of the oil-gas shock absorber device, the vehicle frame is kept substantially parallel to the road surface, reducing the risk of vehicle rollover. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 is a schematic diagram of a prior art vehicle when there is uneven load;

[0053] Figure 2 is a schematic structural diagram of a vehicle according to an embodiment of the present invention;

[0054] Figure 3 is a structural diagram of an oil-gas shock absorber device according to an embodiment of the present invention;

[0055] Figure 4 is a schematic hydraulic principle diagram of an oil-gas suspension system according to the first embodiment of the present invention;

[0056] Figure 5Shows the schematic hydraulic principle diagram of the load - sensing valve group in the closed state in the oil - gas suspension system of the first embodiment of the present invention;

[0057] Figure 6 Shows the schematic hydraulic principle diagram of the load - sensing valve group in the oil - replenishing state in the oil - gas suspension system of the first embodiment of the present invention;

[0058] Figure 7 Shows the schematic hydraulic principle diagram of the load - sensing valve group in the oil - draining state in the oil - gas suspension system of the first embodiment of the present invention;

[0059] Figure 8 Is the schematic diagram of the state of a vehicle equipped with the oil - gas suspension system of the first embodiment of the present invention when driving on an inclined road surface;

[0060] Figure 9 Is the schematic hydraulic principle diagram of the load - sensing valve group in the closed state in the oil - gas suspension system of the second embodiment of the present invention;

[0061] Figure 10 Is the schematic hydraulic principle diagram of the load - sensing valve group in the oil - replenishing state in the oil - gas suspension system of the second embodiment of the present invention;

[0062] Figure 11 Is the schematic hydraulic principle diagram of the load - sensing valve group in the oil - draining state in the oil - gas suspension system of the second embodiment of the present invention;

[0063] Figure 12 Is the schematic diagram of the state of a vehicle equipped with the oil - gas suspension system of the second embodiment of the present invention when driving on an inclined road surface.

[0064] Symbol Explanation

[0065] 1. Vehicle; 2. Carriage; 3. Frame; 4. Wheel;

[0066] 10, 20. Oil - gas suspension system;

[0067] 12. Hydraulic source; 13. Oil - supply pipeline; 14. Liquid storage container;

[0068] 15. Oil - return pipeline; 16. Accumulator; 18, 18a, 18b. Oil - gas shock absorber;

[0069] 20. Axle; 22. Feedback rod; 24. Elastic element;

[0070] 26. Outer cylinder; 27. Inner cylinder; 28. Telescopic cylinder; 29. Annular space; 30. Oil - replenishing and draining port; 31. Check valve; 32. First chamber; 33. Outer side cavity; 34. Second chamber; 35. Second accommodation chamber; 36. Floating piston; 37. Third accommodation chamber; 38. First throttle hole; 39. Second throttle hole;

[0071] 40. Controller; 42. Tilt sensor;

[0072] 100, 200. Load sensing valve groups;

[0073] P. Inlet port; T. Outlet port; A. Oil outlet port;

[0074] 101. Pilot valve; 102. Pilot valve inlet pipeline; 104. Pilot valve outlet pipeline;

[0075] 103. First pilot flow path; 105. Second pilot flow path;

[0076] 106. First intermediate pipeline; 107. Intermediate pipeline; 108. Second intermediate pipeline;

[0077] 110. Damping unit; 112. First chamber; 114. Second chamber; 116. Piston rod; 117. Piston;

[0078] 118. Return spring;

[0079] 120. Throttle valve; 122. First throttle valve; 126. Second throttle valve;

[0080] 130. Balance valve; 132. Balance valve inlet pipeline; 134. Balance valve outlet pipeline;

[0081] 133. Drain flow path; 135. Make-up oil flow path;

[0082] 136. Working port pipeline. Detailed implementation manners

[0083] Next, with reference to the accompanying drawings, the preferred implementation manners of the present invention will be described in detail.

[0084] Figure 2 It is a schematic structural diagram of a vehicle according to an implementation manner of the present invention. For the convenience of description, Figure 2 the coordinate system in the figure indicates the directions of the upper side and the right side. The opposite side of the upper side is the lower side, and the opposite side of the right side is the left side. And, the left and right directions in the specification can also be expressed as "the width direction of the vehicle".

[0085]

Vehicle 1

[0086] As Figure 2 shown, the vehicle 1 can be, for example, a heavy-duty engineering vehicle, which includes a carriage 2, a frame 3 and an axle 20. The axle 20 is located below the frame 3, and wheels 4 are respectively installed at both ends of the axle 20. A plurality of oil-gas shock-absorbing devices 18 are also installed between the frame 3 and the axle 20. The upper end of the oil-gas shock-absorbing device 18 is pivotally connected to the frame 3, and the lower end is pivotally connected to the axle 20. The above-mentioned oil-gas shock-absorbing device 18 is used to transmit the supporting force between the axle 20 and the frame 3.

[0087]

Oil and gas shock absorber 18

[0088] Figure 3 It is a structural diagram of the oil and gas shock absorber 18 according to an embodiment of the present invention.

[0089] The oil and gas shock absorber 18 has a first chamber 32 for accommodating gas and a second chamber 34 for accommodating hydraulic oil.

[0090] Specifically, the oil and gas shock absorber 18 includes an outer cylinder 26, an inner cylinder 27 and a telescopic cylinder 28. The inner cylinder sleeve 27 is arranged inside the outer cylinder 26. The upper end of the telescopic cylinder 28 is located in the annular space 29 between the outer cylinder 26 and the inner cylinder 27, and the telescopic cylinder 28 is slidably connected to the outer cylinder 26 up and down.

[0091] A floating piston 36 that can slide up and down is arranged inside the inner cylinder 27. The floating piston 36 divides the inner cavity of the inner cylinder 27 into a first chamber 32 above the floating piston 36 and a second accommodating chamber 35 below the floating piston 36.

[0092] The annular space 29 is directly communicated with the third accommodating chamber 37 inside the lower side of the telescopic cylinder 28 through an annular gap between the telescopic cylinder 28 and the inner cylinder 27.

[0093] The outer cavity 33 located between the telescopic cylinder 28 and the outer cylinder 26 is communicated through a second throttle hole 39. The second throttle hole 39 is used to slow down the movement speed of the telescopic cylinder 28 relative to the outer cylinder 26 when the telescopic cylinder 28 extends and retracts, thereby playing a shock absorption role for the vehicle.

[0094] A one-way valve 31 and a first throttle hole 38 are arranged at the lower end of the inner cylinder 27. The one-way valve 31 is used to limit the one-way flow of hydraulic oil from the third accommodating chamber 37; the first throttle hole 38 can throttle the hydraulic oil flowing from the second accommodating chamber 35 to the third accommodating chamber 37 when the one-way valve 31 is closed. Thus, when the vehicle is driving on a bumpy road, the hydraulic oil can quickly flow from the third accommodating chamber 37 to the second accommodating chamber 35, causing the floating piston 36 to compress the nitrogen in the first chamber 32, playing a shock absorption role. And it can throttle the fluid flowing from the second accommodating chamber 35 to the third accommodating chamber 37, avoiding the vehicle from shaking due to the too-fast elongation of the oil and gas shock absorber 18.

[0095] The above-mentioned annular space 29, outer cavity 33, second accommodating chamber 35, and third accommodating chamber 37 form the second chamber 34 for accommodating hydraulic oil.

[0096] Due to the compressibility of gas, filling gas in the first chamber 32 can make the oil and gas shock absorber 18 elastic. The above-mentioned gas can be, for example, nitrogen, carbon dioxide, inert gas, etc.

[0097] A charge / discharge oil port 30 communicating with the second chamber 34 is provided on the side wall of the outer cylinder 26. Since oil is incompressible, the telescopic cylinder 28 can be extended downward by filling oil into the second chamber 34, thereby increasing the length of the oil-gas shock absorber 18, and the telescopic cylinder 28 can be retracted by discharging the hydraulic oil in the second chamber 34, reducing the length of the oil-gas shock absorber 18. The hydraulic oil in the second chamber 34 can also be replaced by other incompressible fluids.

[0098] In addition, a Chinese utility model patent CN220726954U previously applied for by the applicant of the present invention discloses an oil-gas shock absorber with a certain structure.

[0099]

Oil-gas suspension system 10

[0100] Figure 4 The hydraulic schematic diagram of the oil-gas suspension system 10 according to an embodiment of the present invention is shown. As Figure 4 shown, the oil-gas suspension system 10 may include a hydraulic source 12 for supplying pressurized hydraulic oil to the oil-gas suspension system 10. The hydraulic source 12 may be, for example, a hydraulic pump, which may be driven by the power of the vehicle engine or an electric motor. The oil-gas suspension system 10 may include a liquid storage container 14 for storing the hydraulic oil circulated in the hydraulic system. The hydraulic source 12 can extract the hydraulic oil from the liquid storage container 14, and after the system circulation, the hydraulic oil finally returns to the liquid storage container 14, thus forming a hydraulic circulation path.

[0101] The hydraulic source 12 is fluidly connected to the inlet port P of the load sensing valve group 100 through an oil supply pipeline 13 to supply hydraulic oil to the load sensing valve group 100. The return port T of the load sensing valve group 100 is fluidly connected to the liquid storage container 14 through a return pipeline 15, and its outlet port A is fluidly connected to the charge / discharge oil port 30 of the oil-gas shock absorber 18a for refilling the oil-gas shock absorber 18a or returning the hydraulic oil discharged from the oil-gas shock absorber 18a to the liquid storage container 14. Preferably, an accumulator 16 can be installed on the oil supply pipeline 13 so that high-pressure hydraulic oil can still be supplied to the oil-gas suspension system 10 when the hydraulic source 12 stops working.

[0102] An oil-gas shock absorber 18a is installed on the left side in the width direction of the vehicle 1, and an oil-gas shock absorber 18b is installed on the right side in the width direction of the vehicle 1. The above-mentioned oil-gas shock absorber 18a can be one or more; correspondingly, the above-mentioned oil-gas shock absorber 18b can also be one or more. When there are multiple oil-gas shock absorbers 18a on the left side in the width direction, the multiple oil-gas shock absorbers 18a on the left side are arranged, for example, in the front-rear direction; when there are multiple oil-gas shock absorbers 18b on the right side in the width direction, the multiple oil-gas shock absorbers 18b on the right side can be arranged, for example, in the front-rear direction. In addition, the compensation and drain ports 30 of the oil-gas shock absorbers 18a or 18b on the same side can be connected in parallel, and the hydraulic oil in the oil-gas shock absorber 18a and the oil-gas shock absorber 18b can flow to each other, so as to form a balanced suspension in the front-rear direction of the vehicle, playing a role in reducing the vibration amplitude.

[0103] Correspondingly, two sets of the above-mentioned oil-gas suspension systems 10 can be provided on the vehicle 1, one set of the oil-gas suspension system 10 is fluidly connected to the oil-gas shock absorber 18a; the other set of the oil-gas suspension system 10 is fluidly connected to the oil-gas shock absorber 18b.

[0104]

Load Sensing Valve Group 100

[0105] The load sensing valve group 100 supplies oil to the oil-gas shock absorber 18a / 18b when needed according to the change in the distance between the vehicle frame 3 and the axle 20 of the vehicle 1, or discharges the hydraulic oil in the oil-gas shock absorber 18b / 18a to adjust the distance between the left or right side of the vehicle frame 3 and the axle 20. For example, Figure 2 In the working condition shown in, the goods on the left side in the carriage 2 are heavy, compressing the gas volume in the left oil-gas shock absorber 18a, and the length of the oil-gas shock absorber 18a is shortened. The vehicle 1 of the present invention can fill the left oil-gas shock absorber 18a with hydraulic oil through the oil-gas suspension system 10 to increase the length of the oil-gas shock absorber 18a, making the vehicle frame 3 substantially parallel to the road surface.

[0106] As Figure 4 shown, the free end of the feedback rod 22 of the load sensing valve group 100 is elastically and detachably connected to the axle 20. The free end of the feedback rod 22 can abut against the elastic element 24, and the elastic element 24 can be fixed on the axle 20. The feedback rod 22 of the load sensing valve group 100 can detect the relative position change between the vehicle frame 3 and the axle 20, and output a corresponding oil flow to the oil-gas shock absorber 18 according to the above relative position change amount, controlling the expansion and contraction of the oil-gas shock absorber 18, and realizing the dynamic variable load control between the vehicle frame 3 and the axle 20. And only when the distance between the axle 20 and the vehicle frame 3 is about to be less than the preset distance will it touch the lower end of the feedback rod 22, avoiding frequent operation of the load sensing valve group 100 and causing a large amount of energy loss.

[0107] In addition, the feedback rod 22 itself can also be elastic. For example, the feedback rod 22 is a helical spring, and the lower end of the feedback rod 22 abuts against the axle 20, which can also achieve the above functions.

[0108] In addition, when there are two axles 20 (referring to the number of axles located at the rear side of the vehicle for bearing the weight of the cargo in the carriage), the elastic element 24 can be, for example, an elastic reed. One end of the elastic reed is connected to the front axle 20 among them, and the other end is connected to the rear axle 20, and the free end of the feedback rod 22 abuts against the middle part of the elastic reed. In this way, the distance between the axle 20 and the vehicle frame 3 is the average value of the distances between the front and rear axles and the vehicle frame 3, which can play a role in buffering the vibration of the vehicle.

[0109] Figure 5 It shows that the load sensing valve group 100 is in the closed state; Figure 6 It shows that the load sensing valve group 100 is in the oil replenishing state; Figure 7 It shows that the load sensing valve group 100 is in the oil discharging state.

[0110] Such as Figure 4 and Figure 5 As shown, when the vehicle frame 3 is in the balanced position (that is, the relative heights of the left and right sides with respect to the axle 20 are the same), the load sensing valve group 100 is in the closed state.

[0111] Specifically, the load sensing valve group 100 includes a damping unit 110 and a balance valve 130. The hydraulic source 12 is communicated with the oil inlet P of the load sensing valve group 100, and the oil return port T of the load sensing valve group 100 is communicated with the liquid storage container 14. The oil outlet A of the load sensing valve group 100 is communicated with the oil replenishing and discharging port 30 of the oil-gas shock absorber 18a.

[0112] The damping unit 110 has a piston rod 116 that can reciprocate up and down. A first chamber 112 is formed in the upper part of the damping unit 110, and a second chamber 114 is formed in the lower part. Between the first chamber 112 and the second chamber 114 is the piston 117 of the damping unit 110. One end of the intermediate pipeline 107 is communicated with the first chamber 112, and the other end is communicated with the second chamber 114. A throttle valve 120 is connected in series on the intermediate pipeline 107, and the throttle valve 120 is used to adjust the flow rate of the fluid in the intermediate pipeline 107, thereby generating a damping effect on the up and down movement of the piston rod 116.

[0113] The upper end of the piston rod 116 is connected to the piston 117, and the lower end of the piston rod 116 is connected to the spool of the balance valve 130. When the vehicle 1 travels on a bumpy road surface, the axle 20 jitters up and down along with the wheels, and then the above jitter is transmitted to the spool of the balance valve 130 through the elastic element 24. Without the damping effect generated by the damping unit 110, the balance valve 130 will frequently switch states, resulting in a large loss of pressure oil. However, by setting the damping unit 110 in the present invention, the movement of the spool of the balance valve 130 can be damped, so that the oil-gas suspension system is protected from the influence of road bumps and the above problems are avoided.

[0114] A return spring 118 is installed in the first chamber 112 of the damping unit 110. The upper end of the return spring 118 abuts against the upper end surface of the inner cavity of the first chamber 112, and the other end abuts against the upper end of the piston 117 of the damping unit 110. When the spool of the balance valve 130 is disengaged from the interaction with the axle 20 (when the feedback rod 22 and the elastic element 24 are provided, it is when the lower end of the feedback rod 22 is disengaged from the elastic element 24), the above return spring 118 can push the spool of the balance valve 130 downward to Figure 6 the state shown.

[0115] It should be noted that the elastic force of the above elastic element 24 is much greater than the elastic force of the return spring 118, so that when the axle 20 acts on the spool of the balance valve 130 through the elastic element 24 and the feedback rod 22, the spool of the balance valve 130 can be pushed to compress the return spring 118 and move upward.

[0116] In Figure 2 the working condition shown, the axle 20 on the left side of the vehicle 1 approaches the vehicle frame 3 under the action of the gravity of the heavier goods on the left side (since the nitrogen in the oil-gas shock absorber 18a is compressed). In the present invention, as Figure 6 shown, the axle 20 pushes the spool of the balance valve 130 upward through the elastic element 24, and the load sensing valve group 100 switches from the closed state to the oil filling state. The high-pressure hydraulic oil at the oil inlet P sequentially enters the oil-gas shock absorber 18a through the balance valve inlet pipeline 132, the oil filling flow path 135 and the working port pipeline 136. The telescopic cylinder 28 of the oil-gas shock absorber 18a extends and the length increases to compensate for the shortened amount caused by the compression of the nitrogen. When the vehicle frame 3 and the axle 20 return to the parallel state, under the action of the return spring 118, the spool of the balance valve 130 moves downward, and the load sensing valve group 100 returns to Figure 5 the closed state shown.

[0117] When the goods in the carriage 2 are unloaded or sorted to be roughly the same in the width direction of the vehicle 1, the compressed nitrogen gas increases in volume due to the reduced load. Since the oil volume in the oil-gas shock absorber 18a is more than that in the oil-gas shock absorber 18b, the left side of the vehicle frame 3 is higher than its right side. Therefore, under the elastic force of the return spring 118 of the oil-gas suspension system on the left side of the vehicle, the spool of the balance valve 130 is pushed downward, and the load sensing valve group 100 switches from the closed state to Figure 7 the oil-draining state shown. As Figure 7 shown, the excessive oil in the oil-gas shock absorber 18a is discharged to the oil return port T through the working port pipeline 136, the oil-draining flow path 133 and the balance valve outlet pipeline 134. When the distance between the vehicle frame 3 and the axle 20 returns to the state where the left and right sides are the same, the left part of the axle 20 pushes the spool of the balance valve 130 upward to Figure 5 the closed state shown.

[0118] As Figure 8 shown, when the vehicle 1 is traveling on an inclined road surface (for example, the left side of the road surface is higher than the right side), due to reasons such as part of the goods (such as powdery, liquid goods, etc.) in the carriage 2 slipping to the right side and the gravity action line shifting to the right, the compression force received by the balance shock absorber 18b is greater than that received by the balance shock absorber 18a. Under the action of the oil-gas suspension system 10, the length of the balance shock absorber 18a on the left side is the same as that of the balance shock absorber 18b on the right side, so that the vehicle frame 3 can be kept parallel to the road surface, without additional roll, reducing the risk of vehicle overturning.

[0119] However, in Figure 8 the state shown, the carriage 2 is still in an inclined state. How to make the bottom surface of the carriage 2 horizontal when the vehicle 1 is traveling on an inclined road surface is a technical problem that those skilled in the art have long hoped to solve. For this reason, the applicant of the present invention has proposed an oil-gas suspension system 20 through long-term exploration and experiments, which can adjust the inclined state of the carriage 2 according to the inclined state of the road surface to make the carriage 2 horizontal to solve the above technical problem.

[0120]

Oil-gas suspension system 20

[0121] The difference between the oil-gas suspension system 20 and the oil-gas suspension system 10 is that a pilot valve 101 is added to the load sensing valve group 200 of the oil-gas suspension system 20, and a control system is correspondingly added. The pilot valve 101 can, for example, selectively supply oil to or drain oil from the oil-gas shock absorbers 18a and 18b in response to the control signal of the control system. The pilot valve 101 can, for example, be an electromagnetic reversing valve. In addition, the pilot valve 101 can be a single three-position solenoid valve, or a combination of multiple two-position solenoid valves or other similar combinations.

[0122] The above control system may include, for example, a controller 40 and an inclination sensor 42. The inclination sensor 42 is fixedly connected to the vehicle frame 3 and is configured to detect the inclination state of the vehicle frame 3 in the left-right direction and send the detected vehicle frame inclination signal to the controller 42. The controller 40 is in signal connection with the inclination sensor 42 and is configured to receive and respond to the above vehicle frame inclination signal, control the pilot valve 101 to switch states, and further control the oil replenishment or oil drainage of the oil-gas shock absorption devices 18a and 18b to adjust the inclination state of the vehicle frame 3 and the carriage 2 in the left-right direction.

[0123] Specifically, as Figure 9 shown, the load sensing valve group 200 includes a pilot valve 101, a damping unit 110, and a balance valve 130. The hydraulic source 12 is communicated with the oil inlet P of the load sensing valve group 200, and the oil return port T of the load sensing valve group 200 is communicated with the liquid storage container 14. The oil outlet A of the load sensing valve group 200 is communicated with the oil replenishment and drainage port 30 of the oil-gas shock absorption device 18a.

[0124] The pilot valve 101 has a first state, a second state, and a third state. Among them, Figure 9 the pilot valve 101 is in the second state; Figure 10 the pilot valve 101 is in the first state; Figure 11 the pilot valve 101 is in the third state.

[0125] In the load sensing valve group 200, the oil inlet P is fluidly connected to the pilot valve inlet pipeline 102 of the pilot valve 101; the oil return port T is fluidly connected to the pilot valve outlet pipeline 104 of the pilot valve 101.

[0126] When the load sensing valve group 200 is in the closed state, both the pilot valve inlet pipeline 102 and the pilot valve outlet pipeline 104 are in the closed state within the pilot valve 101. The first intermediate pipeline 106 and the second intermediate pipeline 108 are in the communicating state within the pilot valve 101.

[0127] The damping unit 110 has a piston rod 116 that can reciprocate up and down. A first chamber 112 is formed in the upper part of the damping unit 110, and a second chamber 114 is formed in the lower part. The piston of the damping unit 110 is located between the first chamber 112 and the second chamber 114. The first intermediate pipeline 106 is fluidly connected to the first chamber 112, and a first throttle valve 122 can be connected in series on the flow path between the first intermediate pipeline 106 and the first chamber 112. The second intermediate pipeline 108 is communicated with the second chamber 114. Preferably, a second throttle valve 126 is connected in series on the flow path between the second intermediate pipeline 108 and the second chamber 114. The above first throttle valve 122 and second throttle valve 126 are respectively configured to adjust the liquid flow rate of their respective flow paths, and further control the movement speed of the piston rod 116.

[0128] The lower end of the piston rod 116 is connected to the spool of the balance valve 130. When filling oil into the first chamber 112, the high-pressure hydraulic oil filled can push the piston rod 116 downward to switch the state of the balance valve 130. Similarly, when filling hydraulic oil into the second chamber 114, the high-pressure hydraulic oil filled can push the piston rod 116 upward to switch the state of the balance valve 130.

[0129] In Figure 9 , the pilot valve 101 is in the second state and the balance valve 130 is in the closed state. Specifically, the balance valve 130 has a balance valve inlet pipeline 132, a balance valve outlet pipeline 134, and a working port pipeline 136. The balance valve inlet pipeline 132 is communicated with the above-mentioned oil inlet P, the balance valve outlet pipeline 134 is communicated with the above-mentioned oil return port T, and the working port pipeline 136 is communicated with the charge and discharge oil port 30 of the oil-gas shock absorber 18a.

[0130] When the balance valve 130 is in the closed state, inside the balance valve 130, the above-mentioned balance valve inlet pipeline 132, balance valve outlet pipeline 134, and working port pipeline 136 are all in the closed state.

[0131] As Figure 9 shown, since the first intermediate pipeline 106 and the second intermediate pipeline 108 are in the communicating state, that is, the first chamber 112 and the second chamber 114 of the damping unit 110 are in the communicating state. The first throttle valve 122 and the second throttle valve 126 can play a damping role in the up and down movement of the piston rod 116 of the damping unit 110. At this time, Figure 9 the state of the oil-gas suspension system 20 shown is similar to the working mode of the oil-gas suspension system 10 (i.e., without the pilot valve 101), and the balance valve 130 is in the closed state, which will not be elaborated here.

[0132] When the vehicle just drives onto an inclined road surface (taking the left side of the road surface being higher than the right side as an example for description), the inclination sensor 42 detects that the vehicle frame 3 is in an inclined state and sends a signal to the controller 40. The controller 40 then controls the pilot valve 101 to act and switch to Figure 10 the state shown. Figure 10 In Figure 11In the shown operating state, through the first pilot flow path 103 described above, the oil inlet P is in fluid connection with the second chamber 114 of the damping unit 110. Through the second pilot flow path 105 described above, the pilot valve outlet pipeline 104 is in fluid connection with the first intermediate pipeline 106. Furthermore, the high-pressure fluid at the oil inlet P can be filled into the second chamber 114 of the damping unit 110 through the first pilot flow path 103 to push the piston rod 116 upward. The fluid in the first chamber 112 of the damping unit 110 then flows to the oil return port T through the second pilot flow path 105. The upward movement of the piston rod 116 further drives the spool of the balance valve 130 upward, forming a supplementary oil flow path 135 between the balance valve outlet pipeline 134 and the working port pipeline 136. The high-pressure fluid at the oil inlet P can then be filled into the oil-gas shock absorber 18b on the right side of the vehicle through the supplementary oil flow path 135. The telescopic cylinder 28 of the oil-gas shock absorber 18b extends, and the right side of the vehicle frame 3 is lifted, so that the left and right sides of the vehicle frame 3 are approximately at the same horizontal height (as Figure 12 shown).

[0133] When the vehicle 1 travels on a flat road surface again, in the Figure 11 shown state, the pilot valve 101 is in the third state, and the first pilot flow path 103 and the second pilot flow path 105 are formed inside the pilot valve 101. Through the first pilot flow path 103, the pilot valve inlet pipeline 102 is in fluid connection with the first intermediate pipeline 106; through the second pilot flow path 105, the pilot valve outlet pipeline 104 is in fluid connection with the second intermediate pipeline 108. Furthermore, the high-pressure fluid at the oil inlet P replenishes oil to the first chamber 112 of the damping unit 110 through the first pilot flow path 103, pushing the piston rod 116 downward. The fluid in the second chamber 114 then returns to the oil return port T through the second pilot flow path 105.

[0134] The downward movement of the piston rod 116 further pushes the spool of the balance valve 130 downward, forming an oil discharge flow path 133 inside the balance valve 130. The balance valve inlet pipeline 132 is in fluid connection with the working port pipeline 136 through the oil discharge flow path 133. The fluid in the oil-gas shock absorber 18b flows to the oil return port T through the supplementary oil flow path 135, and the height of the oil-gas shock absorber 18b decreases to reduce the height of the same side of the vehicle frame 3 as the oil-gas shock absorber 18b, thereby maintaining the left and right sides of the vehicle frame 3 approximately at the same height.

[0135] It should be noted that for the same vehicle 1, two oil-gas suspension systems 20 can be set. One set of oil-gas suspension system 20 is in fluid connection with the oil-gas shock absorber 18a on the left side, and the other set of oil-gas suspension system 20 is in fluid connection with the oil-gas shock absorber 18b on the right side. The controller 40 is respectively in signal connection with the pilot valves 101 in each oil-gas suspension system 20, so as to enable the oil-gas shock absorbers 18a and 18b on the left and right sides to work in coordination.

[0136] Thus, as Figure 12 shown, when the vehicle 1 is traveling on an inclined road surface with a higher height on the left side, it is also possible to achieve the purpose of making the left and right sides of the vehicle frame 1 at the same height by simultaneously discharging oil from the left oil-gas shock absorber 18a. Alternatively, the right oil-gas suspension system 20 can be started first to fill the right oil-gas shock absorber 18b with oil. After a predetermined time delay (for example, 1 to 5 seconds), if the inclination sensor 42 detects that the inclination angle of the vehicle frame 3 (the angle between the upper surface of the axle and the horizontal plane) is still not less than the preset value, the left oil-gas shock absorber 18a is shortened. Under the combined action of the oil-gas shock absorber 18a and the oil-gas shock absorber 18b, the vehicle frame 3 can quickly reach a horizontal state.

[0137] Similarly, when the vehicle 1 travels on a horizontal road surface again, it is also possible to first discharge a part of the hydraulic oil in the right oil-gas shock absorber 18b. After a predetermined time delay, if the inclination sensor 42 detects that the inclination angle of the vehicle frame 3 is still not less than the preset value, the left oil-gas shock absorber 18a is filled with oil to quickly make the vehicle frame 3 reach a horizontal state.

[0138] The above has described in detail the oil-gas suspension system, vehicle and method of the preferred embodiment of the present invention. However, those skilled in the art can make various modifications, changes, combinations, etc. on this basis, and these modifications, changes, combinations all fall within the protection scope of the claims of this application.

Claims

1. An oil-gas suspension system, characterized in that, comprising: hydropneumatic shock absorbers disposed on both sides in the vehicle width direction, one end of each hydropneumatic shock absorber being connected to the vehicle frame and the other end being connected to the axle; the hydropneumatic shock absorber defining a first chamber for accommodating gas and a second chamber for accommodating liquid; the first chamber and the second chamber being separated by a floating piston; the volume of the gas in the first chamber being inversely correlated with the value of the axial pressure load received by the hydropneumatic shock absorber, and the length of the hydropneumatic shock absorber being directly correlated with the volume of the liquid in the second chamber, a pressure source configured to supply pressurized liquid to the second chamber; a liquid storage container configured to receive liquid from the second chamber; a load sensing valve group fluidly connected to the hydropneumatic shock absorber; the load sensing valve group being configured to fluidly connect one of the pressure source and the liquid storage container to the second chamber; wherein, on at least one side in the vehicle width direction, when the distance between the axle and the vehicle frame is less than a preset distance, liquid is supplemented from the pressure source into the second chamber of the hydropneumatic shock absorber on that side; when the distance between the axle and the vehicle frame is greater than the preset distance, liquid is discharged from the hydropneumatic shock absorber on that side into the liquid storage container; the load sensing valve group has a closed state in which the second chamber is closed, a refueling state in which the pressure source is communicated with the second chamber, and a drain state in which the liquid storage container is communicated with the second chamber; the load sensing valve group has a balance valve, the balance valve having a balance valve inlet pipeline communicated with the pressure source, a balance valve outlet pipeline communicated with the liquid storage container, and a working port pipeline communicated with the second chamber; in the refueling state, the balance valve inlet pipeline is communicated with the working port pipeline, in the drain state, the balance valve outlet pipeline is communicated with the working port pipeline; in the closed state, the balance valve inlet pipeline, the balance valve outlet pipeline, and the working port pipeline are all closed; the load sensing valve group is fixed to the vehicle frame, and the spool of the balance valve is elastically and detachably connected to the axle; the load sensing valve group further includes a damping unit, the damping unit defining a first chamber and a second chamber, the first chamber and the second chamber being configured to have a current-limiting communication path; a piston is provided between the first chamber and the second chamber, and the piston is connected to the spool of the balance valve.

2. The hydropneumatic suspension system according to claim 1, wherein in the damping unit, a return spring for pushing the spool downward when the spool of the balance valve is separated from the axle is provided in the first chamber; the load sensing valve group includes a feedback rod, one end of the feedback rod being connected to the spool of the balance valve and the other end being abutted against an elastic element fixed to the axle; the elastic force of the elastic element is greater than the elastic force of the return spring; the elastic element is an elastic reed, when two adjacent axles are in the front-rear direction of the vehicle, both ends of the elastic reed are respectively connected to the front axle and the rear axle; the lower end of the feedback rod abuts against the middle part of the elastic reed.

3. A vehicle, characterized in that, including: Axle, with wheels respectively provided at both ends of the axle; Frame, located on the upper side of the axle; Hydropneumatic shock absorbers provided on both sides in the vehicle width direction, one end of the hydropneumatic shock absorber is connected to the frame, and the other end is connected to the axle; the hydropneumatic shock absorber defines a first chamber for accommodating gas and a second chamber for accommodating liquid; when the hydropneumatic shock absorber is subjected to an axial pressure, it shortens due to the compression of the volume of the gas in the first chamber, and the length of the hydropneumatic shock absorber is positively correlated with the volume of the liquid in the second chamber, Pressure source, configured to supply pressurized liquid to the second chamber; Liquid storage container, configured to receive liquid from the second chamber; Load sensing valve group, fluidly connected to the hydropneumatic shock absorber; the load sensing valve group is configured to fluidly connect one of the pressure source and the liquid storage container to the second chamber; Wherein, on at least one side in the vehicle width direction, when the distance between the axle and the frame is less than a preset distance, liquid is supplemented from the pressure source into the second chamber of the hydropneumatic shock absorber on this side; when the distance between the axle and the frame is greater than the preset distance, liquid is discharged from the hydropneumatic shock absorber on this side to the liquid storage container; The load sensing valve group has a closed state in which the second chamber is closed, a refueling state in which the pressure source is communicated with the second chamber, and a draining state in which the liquid storage container is communicated with the second chamber; The load sensing valve group has a balance valve, the balance valve has a balance valve inlet pipeline communicated with the pressure source, a balance valve outlet pipeline communicated with the liquid storage container, and a working port pipeline communicated with the second chamber; In the refueling state, the balance valve inlet pipeline is communicated with the working port pipeline, In the draining state, the balance valve outlet pipeline is communicated with the working port pipeline; In the closed state, the balance valve inlet pipeline, the balance valve outlet pipeline and the working port pipeline are all closed; The load sensing valve group is fixed to the frame, and the valve core of the balance valve is elastically and detachably connected to the axle; The load sensing valve group further includes a damping unit, the damping unit defines a first chamber and a second chamber, and the first chamber and the second chamber are configured to have a current-limiting communication path; There is a piston between the first chamber and the second chamber, and the piston is connected to the valve core of the balance valve.

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