CN110816190A

CN110816190A - Vehicle suspension system

Info

Publication number: CN110816190A
Application number: CN201810900800.7A
Authority: CN
Inventors: 郭茂春; 周非
Original assignee: Shanghai Excellent Soft Automotive Technology Co Ltd
Current assignee: Shanghai Excellent Soft Automotive Technology Co Ltd
Priority date: 2018-08-08
Filing date: 2018-08-08
Publication date: 2020-02-21

Abstract

The invention relates to a vehicle suspension system which is arranged between a vehicle frame and an axle and comprises a single-acting oil cylinder, a single-cylinder oil way, a connecting oil way, an energy accumulator assembly, a main oil way and the like. The vehicle suspension system provided by the invention has the advantages that the single-acting oil cylinder replaces a double-acting oil cylinder in the prior art, the oil cylinder structure is simplified, the cost is reduced, the control valve group and the control process are simple, and the control and the installation are convenient. The energy accumulator component adopts a two-stage pressure type structure consisting of a low-pressure energy accumulator and a high-pressure energy accumulator, can adapt to loads with large changes, realizes the functions of large-range buffering and empty and full-load self-adaption, and has good buffering and vibration reduction effects on a vehicle suspension system under the conditions of different loads.

Description

Vehicle suspension system

Technical Field

The invention relates to the technical field of vehicles, in particular to a vehicle suspension system arranged between a vehicle frame and an axle.

Background

Suspension refers to a connection structure system between a vehicle body or a vehicle frame and a wheel or an axle, and is an important assembly part in a vehicle, and is related to various service performances of the vehicle. The suspension serves to transmit force and torque acting between the wheels and the frame, and to cushion impact force transmitted from an uneven road surface to the frame or the vehicle body and to attenuate vibration caused by the impact force, thereby ensuring smooth driving of the vehicle. When the vehicle is driven on a road surface, the vehicle is subjected to vibration and impact due to changes in the ground, and the force of the impact is partially absorbed by the tire, but most of the impact is absorbed by the suspension provided between the vehicle frame and the axle.

The traditional suspension mostly adopts a spring suspension or an air suspension, the utilization rate of the air suspension on a heavy truck exceeds 80 percent in foreign countries, the utilization rate on a high-speed passenger car and a luxury city passenger car reaches 100 percent, and the air suspension is also installed on part of cars. The working principle of the air suspension is that an air compressor forms compressed air, and the compressed air is sent to an air chamber of a spring and a shock absorber, so that the height of a vehicle is changed, and the aim of buffering and damping is achieved.

However, due to the high compressibility of air, the problems of slow response speed and long adjustment time can occur when the air suspension is used, and meanwhile, the air suspension can also change along with the change of load after being lifted and lowered, and needs to be lifted and lowered again or for multiple times. In addition, the air suspension has elasticity after lifting, and the elasticity is larger particularly in no-load or light-load conditions, so that the stability of loading and unloading goods is seriously influenced. Thus, hydro-pneumatic spring suspensions have emerged.

The hydro-pneumatic spring cylinder in the hydro-pneumatic spring suspension uses gas as an elastic medium and liquid as a force transmission medium, has good buffering capacity and vibration reduction effect, can also adjust the height of a frame, and is suitable for heavy vehicles and motor buses. The gas in the hydro-pneumatic spring cylinder is typically an inert gas, often nitrogen.

In the hydro-pneumatic spring suspension in the prior art, a double-acting hydro-pneumatic spring cylinder is selected for the hydro-pneumatic spring cylinder, and in order to better control the double-acting hydro-pneumatic spring cylinder, the oil circuit of the double-acting hydro-pneumatic spring cylinder is often designed to be very complicated, and the cost is high. Meanwhile, the stroke of the double-acting hydro-pneumatic spring cylinder is limited by the installation space between the frame and the axle, and the buffering and vibration damping effects are poor.

Disclosure of Invention

The invention aims to provide a vehicle suspension system to solve the problems of low response speed and poor stability of an air suspension and the problems of complex structure and poor buffering and damping effects of a double-acting hydro-pneumatic spring suspension in the prior art.

In order to achieve the above object, the present invention provides a vehicle suspension system provided between a vehicle frame and an axle, comprising: the single-acting oil cylinder is respectively connected with the frame and the axle and can form elastic support between the frame and the axle; the single-cylinder oil way is communicated with the oil cavity of the single-acting oil cylinder, and the single-cylinder oil way further comprises a connecting oil way, an energy accumulator assembly and a main oil way, wherein the main oil way is communicated with the single-cylinder oil way and the energy accumulator assembly through the connecting oil way, and hydraulic oil of the main oil way can sequentially flow through the connecting oil way and the single-cylinder oil way to enter the oil cavity of the single-acting oil cylinder.

Optionally, a first one-way throttle valve is arranged on the single-cylinder oil path, and hydraulic oil in the single-acting oil cylinder can flow into the connecting oil path through a one-way valve in the first one-way throttle valve.

Optionally, the vehicle suspension system further comprises: the double-acting oil cylinder is respectively connected with the frame and the axle and can form elastic support between the frame and the axle; the hydraulic oil of the main oil way can enter the double-cylinder oil way and the connecting oil way.

Optionally, the two-cylinder oil circuit comprises: the first pipeline is used for communicating rod oil chambers of the pair of double-acting oil cylinders; the second pipeline is used for communicating rodless oil chambers of the pair of double-acting oil cylinders; and the third pipeline is used for communicating the first pipeline and the second pipeline.

Optionally, a first stop valve is disposed on the third pipeline, and the hydraulic oil in the first pipeline can flow into the second pipeline after flowing through the first stop valve on the third pipeline.

Optionally, the connection oil path is communicated with the third pipeline, and the hydraulic oil in the first pipeline can flow into the connection oil path through the first stop valve after flowing into the third pipeline.

Optionally, a second stop valve and a second one-way throttle valve are arranged on the connecting oil path, and hydraulic oil of the double-cylinder oil path can flow into the connecting oil path through a one-way valve and the second stop valve in the second one-way throttle valve and flow into the single-cylinder oil path and the energy accumulator assembly through the connecting oil path.

Optionally, a third stop valve is arranged between the energy accumulator assembly and the connecting oil path, and hydraulic oil in the connecting oil path can flow into the energy accumulator assembly through the third stop valve.

Optionally, the accumulator assembly comprises a high pressure accumulator and a low pressure accumulator, the high pressure accumulator being in communication with the low pressure accumulator.

Alternatively, the main oil passage includes a filter, a pump, a main check valve, a main stop valve, and an oil tank, and when supplying oil, hydraulic oil in the oil tank is sucked by the pump after passing through the filter, the pump can discharge the sucked hydraulic oil, and hydraulic oil discharged from the pump can flow from the main oil passage into the connection oil passage after passing through the main check valve and the main stop valve.

Optionally, the main oil path includes a filter, a pump, a main check valve, a main stop valve, and an oil tank, and during oil supply, hydraulic oil in the oil tank is sucked by the pump after passing through the filter, the pump can discharge the sucked hydraulic oil, and the hydraulic oil discharged from the pump can flow into the dual-cylinder oil path from the main oil path after passing through the main check valve and the main stop valve.

Optionally, the vehicle suspension system further includes a safety oil path, and the safety oil path is provided with an overflow valve, so that the hydraulic oil flowing out from the pump can flow into the safety oil path and return to the oil tank after passing through the overflow valve.

Optionally, the vehicle suspension system further includes an oil return path, the oil return path is communicated with the main oil path, an oil return stop valve is disposed on the oil return path, when the system supplies oil, hydraulic oil flowing out from the pump can enter the oil return path after passing through the main check valve, and returns to the oil tank after passing through the oil return stop valve; when the system returns oil, the hydraulic oil outside the main oil path can flow into the main oil path, can flow into the oil return path after flowing through the main stop valve, and returns to the oil tank after passing through the oil return stop valve.

Optionally, the vehicle suspension system further comprises a reversing control oil path, the reversing control oil path is respectively communicated with the double-cylinder oil path and the main oil path, and the reversing control oil path is provided with a reversing valve.

Optionally, the reversing valve is a three-position four-way reversing valve, the sliding valve performance code of the reversing valve is P, an A port of the reversing valve is communicated with the second pipeline, a B port of the reversing valve is communicated with the first pipeline, a T port of the reversing valve is communicated with the main oil way, the P port of the reversing valve is communicated with the oil tank, and hydraulic oil flowing out of the pump can flow into the reversing valve through the T port of the reversing valve after flowing through the main one-way valve and can flow into the double-cylinder oil way through the A port or the B port of the reversing valve.

Optionally, a hydraulic lock is arranged between the reversing valve and the double-cylinder oil way.

Optionally, the single-acting cylinder is a single-acting hydro-pneumatic spring cylinder.

Optionally, the single-acting cylinder is a single-acting hydro-pneumatic spring cylinder and the double-acting cylinder is a double-acting hydro-pneumatic spring cylinder.

Optionally, the vehicle suspension system further comprises a connecting arm, the single-acting cylinder is connected with the axle through the connecting arm, one end of the connecting arm is hinged to the frame, the other end of the connecting arm is hinged to a piston rod of the single-acting cylinder, a cylinder body of the single-acting cylinder is hinged to the frame, and the axle is arranged on the connecting arm along the width direction of the frame.

Optionally, the vehicle suspension system further comprises a connecting arm, the single-acting cylinder and the double-acting cylinder are both connected with the axle through the connecting arm, one end of the connecting arm is hinged to the frame, the other end of the connecting arm is hinged to a piston rod of the single-acting cylinder and a piston rod of the double-acting cylinder respectively, a cylinder body of the single-acting cylinder and a cylinder body of the double-acting cylinder are both hinged to the frame, and the axle is arranged on the connecting arm along the width direction of the frame.

As described above, the vehicle suspension system provided by the invention replaces the double-acting oil cylinder in the prior art with the single-acting oil cylinder, so that the structure of the oil cylinder is simplified, the cost is reduced, meanwhile, the single-acting oil cylinder only needs to be driven in a single direction through hydraulic pressure, the vehicle can be restored to a compression state by the gravity of a vehicle frame, a control oil way and a connecting oil way are simplified, a control valve group and a control process are simpler, and the control and the installation are convenient.

Furthermore, the energy accumulator assembly adopts a two-stage pressure type structure consisting of a low-pressure energy accumulator and a high-pressure energy accumulator, can adapt to working conditions with large load range change, realizes the self-adaptive function of large-range buffer span and empty and full load, and has good buffer and vibration reduction effects on the vehicle suspension system under the conditions of no load, light load, heavy load and full load.

In order that the foregoing and other objects, features, and advantages of the invention will be readily understood, a preferred embodiment of the invention will be hereinafter described in detail with reference to the accompanying drawings.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

FIG. 1 schematically illustrates a schematic structural diagram of a vehicle suspension system in one embodiment of the present invention;

FIG. 2 schematically illustrates a schematic structural diagram of a vehicle suspension system in one embodiment of the present invention;

FIG. 3 schematically illustrates a schematic structural diagram of a vehicle suspension system in one embodiment of the present invention;

FIG. 4 is a schematic illustration of the connections of the directional valve of FIG. 3 with the spool in the neutral position;

fig. 5 schematically shows a structural layout of a suspension system of a vehicle in an embodiment of the invention.

Wherein the figures include the following reference numerals:

1. a vehicle suspension system; 10. a single-acting cylinder; 100. a cylinder body of a single-acting cylinder; 101. an oil chamber of the single-acting cylinder; 102. a piston rod of the single-acting cylinder; 11. a single cylinder oil circuit; 110. a first one-way throttle valve; 12. connecting an oil way; 120. a second one-way throttle valve; 121. a second stop valve; 122. a third stop valve; 13. an accumulator assembly; 130. a high pressure accumulator; 131. a low pressure accumulator; 14. a main oil path; 140. a filter; 141. a pump; 142. a main check valve; 143. a master cut-off valve; 144. an oil tank; 15. a double-acting oil cylinder; 150. a cylinder body of the double-acting oil cylinder; 151. a piston rod of the double-acting oil cylinder; 152. a rodless oil chamber of the double-acting oil cylinder; 153. a rod oil chamber of the double-acting oil cylinder; 16. a double-cylinder oil circuit; 160. a second pipeline; 161. a first pipeline; 162. a third pipeline; 163. a first shut-off valve; 17. a safety oil path; 170. an overflow valve; 18. an oil return path; 180. an oil return stop valve; 19. a reversing control oil path; 190. a diverter valve; 191. hydraulic locking; 2. a frame; 20. connecting a bracket; 21. a hinged frame; 3. an axle; 4. a connecting arm; 5. a wheel; 6. and (6) integrating the blocks.

Detailed Description

The following description of the embodiments of the present invention is provided for illustrative purposes, and other advantages and effects of the present invention will become apparent to those skilled in the art from the present disclosure. While the invention will be described in conjunction with the preferred embodiments, it is not intended that features of the invention be limited to these embodiments. On the contrary, the invention is described in connection with the embodiments for the purpose of covering alternatives or modifications that may be extended based on the claims of the present invention. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. The invention may be practiced without these particulars. Moreover, some of the specific details have been left out of the description in order to avoid obscuring or obscuring the focus of the present invention.

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.

The traditional suspension mostly adopts a spring suspension or an air suspension, and due to the fact that air is high in compressibility, the problems of low response speed and long adjusting time can occur when the air suspension is used. In addition, in the hydro-pneumatic spring suspension in the prior art, the hydro-pneumatic spring cylinder selects the double-acting hydro-pneumatic spring cylinder, the control oil path of the double-acting hydro-pneumatic spring cylinder is complex, the installation is inconvenient, the control process is complicated, and the cost is high. Meanwhile, the stroke of the double-acting hydro-pneumatic spring cylinder is limited by the installation space between the frame and the axle, and the effect of buffering and damping is not ideal.

Referring to fig. 1 in combination with fig. 5, an embodiment of the present invention provides a vehicle suspension system 1, wherein the vehicle suspension system 1 is disposed between a vehicle frame 2 and an axle 3, and comprises a single-acting cylinder 10 and a single-cylinder oil path 11, wherein the single-acting cylinder 10 is connected with the vehicle frame 2 and the axle 3 respectively, and can form an elastic support between the vehicle frame 2 and the axle 3, and the single-cylinder oil path 11 is communicated with an oil chamber 101 of the single-acting cylinder 10. Meanwhile, the vehicle suspension system 1 further comprises a connecting oil path 12, an energy accumulator assembly 13 and a main oil path 14, wherein the main oil path 14 is communicated with the single-cylinder oil path 11 and the energy accumulator assembly 13 through the connecting oil path 12, and hydraulic oil of the main oil path 14 can sequentially flow through the connecting oil path 12 and the single-cylinder oil path 11 to enter an oil chamber 101 of the single-acting cylinder 10.

In the present embodiment, an upstream end of the connecting oil path 12 communicates with the main oil 14, a downstream end of the connecting oil path 12 communicates with the accumulator assembly 13, the single-acting cylinder 10 and the single-cylinder oil path 11 communicate with the connecting oil path 12 in turn, the main oil path 14 supplies the hydraulic oil to the single-cylinder oil path 11 and the accumulator assembly 13 through the connecting oil path 12, the single-cylinder oil path 11 communicates with the oil chamber 100 of the single-acting cylinder 10, and the hydraulic oil supplied from the main oil path 14 can be delivered to the oil chamber 100 of the single-acting cylinder 10. The accumulator assembly 13, as an elastic element in the vehicle suspension system 1, is communicated with the oil chamber 100 of each single-acting cylinder 10 through the connecting oil passage 12, and can well play a role in buffering and damping vibration. The whole vehicle suspension system 1 is simple in structure, reasonable in design, convenient to install and operate.

Specifically, referring to fig. 1 in combination with fig. 5, in the vehicle suspension system 1 provided in the present embodiment, before use, the main oil passage 14 supplies oil to the accumulator assembly 13 and the oil chamber 100 of the single-acting cylinder 10 through the connecting oil passage 12, and under the action of hydraulic oil pressure, the piston rod 102 of the single-acting cylinder 10 extends, and the vehicle frame 2 is lifted to a proper height through the extension of the piston rod 102 of the single-acting cylinder 10, so that the height adjustment of the vehicle frame 2 can be realized. In the driving process, the vehicle can be vibrated and impacted due to the change of the ground height, the axle 3 can transmit most of the vibration and the impact to the piston rod 102 of the single-acting oil cylinder 10, the piston rod 102 can compress hydraulic oil in the oil cavity 100 of the single-acting oil cylinder 10, the pressure in the oil cavity 100 is increased, the increased pressure is transmitted to the energy accumulator assembly 13 through the single-cylinder oil way 11 and the connecting oil way 12 and is absorbed by the energy accumulator assembly 13, the vehicle can stably drive, and the buffering and vibration reduction effects are realized. After the vehicle is stopped and stable, the oil return path 18 is opened, and the hydraulic oil in the oil chamber 100 can return to the oil tank 144 from the oil return path 18 after passing through the single-cylinder oil path 11 and the connecting oil path 12 under the action of the gravity of the vehicle frame 2, so that the piston rod 102 retracts into the cylinder body 100 of the single-acting oil cylinder 10, and the whole vehicle frame 2 is lowered.

Compared with the prior art, the vehicle suspension system 1 provided by the invention has the advantages that the single-acting oil cylinder 10 is used for replacing a double-acting oil cylinder in the prior art, the structure of the oil cylinder is simplified, the cost is reduced, meanwhile, the single-acting oil cylinder 10 only needs to be driven in a single direction through hydraulic pressure, the compression state can be recovered by the gravity of the vehicle frame 2, the control oil path and the connection oil path are simplified, and the control and the installation are convenient. The vehicle suspension system 1 provided by the invention uses hydraulic oil as a force transmission medium, and solves the problems of low reaction speed and long adjustment time of an air suspension in the prior art.

It should be noted that the number of the single-cylinder oil path 11 and the single-acting cylinder 10 is not limited in the present invention, as long as the damping and the height adjustment of the frame 2 can be realized. The specific number can be set according to the number of axles 3 on the vehicle, and the both ends of axle 3 all can set up single-action hydro-cylinder 10, and single-action hydro-cylinder 10 all communicates with the single cylinder oil circuit 11 that corresponds. In the present embodiment, four single-cylinder oil passages 11 and four single-acting cylinders 10 are provided, and are provided at both ends of the two axles 3 arranged in parallel.

Referring to fig. 1 in combination with fig. 5, the single cylinder oil path 11 of the present invention is provided with a first one-way throttle valve 110, and hydraulic oil in the single-acting cylinder 10 can flow into the connecting oil path 12 through the one-way valve in the first one-way throttle valve 110. In the present embodiment, when the piston rod 102 of the single-acting cylinder 10 is impacted, the piston rod 102 compresses the hydraulic oil in the oil chamber 100 of the single-acting cylinder 10, so that the pressure in the oil chamber 100 increases. At this time, the pressure in the oil chamber 100 can be quickly transmitted to the energy storage assembly 13 from the single-cylinder oil path 11 through the check valve in the first one-way throttle valve 110, and the gas inside the energy storage assembly 13 can be quickly compressed to timely absorb the impact, so that the vehicle runs stably, and the buffering and vibration damping effects are realized. When the buffering reaches the balance, the compressed gas in the energy accumulator component 13 begins to expand, and the hydraulic oil flows out of the energy accumulator component 13 and returns to the single-cylinder oil path 11 through the connecting oil path 12. At this time, the check valve of the first one-way throttle valve 110 is closed, the returned hydraulic oil can only pass through the throttle valve of the first one-way throttle valve 110, the throttle valve of the first one-way throttle valve 110 generates a damping effect on the returned hydraulic oil, the vibration generated by the expansion of the gas inside the accumulator assembly 13 is damped, and the damping coefficient of the vehicle suspension system 1 changes nonlinearly with the speed of the hydraulic oil flowing through the throttle valve. The nonlinear variable damping is an ideal effect pursued by the vehicle suspension system 1 and can be realized through reasonable selection of parameters such as the cylinder diameter of the oil cylinder, the damping aperture of the throttle valve, the pre-charging pressure inside the energy accumulator assembly 13 and the like, and the nonlinear variable damping can enable the vehicle suspension system 1 to achieve the best buffering vibration attenuation effect and improve the smoothness and the stability of vehicle running.

Referring to fig. 2 in combination with fig. 5, the vehicle suspension system 1 of the present invention further includes a double-acting cylinder 15 and a double-cylinder oil passage 16, wherein the double-acting cylinder 15 is connected to the frame 2 and the axle 3, respectively, and is capable of forming an elastic support between the frame 2 and the axle 3, the double-cylinder oil passage 16 is communicated with the connecting oil passage 12 and the main oil passage 14, respectively, and hydraulic oil of the main oil passage 14 can enter the double-cylinder oil passage 16 and the connecting oil passage 12.

In the present embodiment, the main oil path 14 communicates with the two-cylinder oil path 16, the two-cylinder oil path 16 communicates with the connecting oil path 12, and the hydraulic oil in the main oil path 14 can flow into the connecting oil path 12 through the two-cylinder oil path 16, so that the double-acting cylinder 15 and the single-acting cylinder 10 can be synchronously adjusted. The single-acting oil cylinder 10 and the double-acting oil cylinder 15 are supplied with oil, so that the frame 2 can be lifted, and the height of the frame 2 can be conveniently adjusted. In addition, when the vehicle is empty or under light load, the main oil way 14 fills oil into the rod oil cavity 153 of the double-acting oil cylinder 15 through the double-cylinder oil way 16, so that the axle 3 connected with the piston rod 151 of the double-acting oil cylinder 15 can be lifted, the function of lifting part of the axle 3 is realized, the number of the wheels 5 contacting with the ground is reduced, and the purposes of saving oil consumption and reducing tire wear are achieved.

It should be noted that the present invention does not limit the number of the double-acting cylinders 15, as long as the functions of damping, adjusting the height of the frame 2, and lifting the axle 3 can be realized. The specific number can be set according to the number of the axles 3, two ends of one axle 3 are respectively provided with a double-acting oil cylinder 15, and the double-acting oil cylinders 15 are communicated through a double-cylinder oil way 16. In the present embodiment, the number of the double-acting cylinders 15 is two, and the double-acting cylinders are symmetrically arranged at both ends of one axle 3. In addition, the arrangement positions of the double-acting oil cylinder 15 and the double-cylinder oil way 16 are not limited, the double-acting oil cylinder 15 and the double-cylinder oil way 16 can be arranged at the upstream of the connecting oil way 12, can be arranged at the downstream of the connecting oil way 12, and can be arranged at the middle section of the connecting oil way 12 as long as the effective communication and the reliable control between the oil ways can be realized.

Referring to fig. 2 in conjunction with fig. 5, the dual cylinder circuit 16 of the present invention includes a first line 161, a second line 160 and a third line 162, wherein the first line 161 is used to communicate the rod chambers 153 of the pair of double acting cylinders 15, the second line 160 is used to communicate the rodless chambers 152 of the pair of double acting cylinders 15, and the third line 162 is used to communicate the first line 161 and the second line 160.

In the present embodiment, the main oil passage 14 communicates with the first pipeline 161, the hydraulic oil of the main oil passage 14 can enter the rod oil chamber 153 of the double-acting cylinder 15 through the first pipeline 161 to push the piston rod 151 of the double-acting cylinder 15 to retract into the cylinder body 150 of the double-acting cylinder 15, and the hydraulic oil of the main oil passage 14 can also enter the rod-free oil chamber 152 of the double-acting cylinder 15 through the third pipeline 162 and the second pipeline 160 to push the piston rod 151 of the double-acting cylinder 15 to extend out of the cylinder body 150 of the double-acting cylinder 15. The third pipe 162 connects the first pipe 161 and the second pipe 160, so that the main oil passage 14 can simultaneously supply oil to the rodless oil chamber 152 and the rod oil chamber 153 of the double-acting cylinder 15, and at this time, the difference of the radial cross-sectional areas of the rodless oil chamber 152 and the rod oil chamber 153 is the radial cross-sectional area of the piston rod 151, that is, the double-acting cylinder 15 in this state is functionally equivalent to the single-acting cylinder 10, and the damping effect can be well achieved.

Referring to fig. 2 in combination with fig. 5, the third pipeline 162 of the present invention is provided with a first stop valve 163, and the hydraulic oil in the first pipeline 161 can flow into the second pipeline 160 after passing through the first stop valve 163 on the third pipeline 162. The connection oil passage 12 communicates with the third line 162, and the hydraulic oil in the first line 161 can flow into the connection oil passage through the first shutoff valve 163 after flowing into the third line 162.

In the present embodiment, the third pipeline 162 is provided with the first stop valve 163, and the first stop valve 163 can control the on/off of the third pipeline 162 to switch the functions of the double-acting cylinder 15. In addition, the third line 162 is also communicated with the connecting oil passage 12, and is capable of transferring the hydraulic oil in the two-cylinder oil passage 16 to the connecting oil passage 12. The junction of the third conduit 162 and the connecting oil passage 12 may be located at the same position as the junction of the third conduit 162 and the second conduit 160.

Specifically, referring to fig. 2 in conjunction with fig. 5, when the first cut valve 163 is opened, the third line 162 is in a passage state, enabling communication between the first line 161 and the second line 160. At this time, the rodless oil chamber 152 and the rod oil chamber 153 of the double-acting cylinder 15 communicate with each other, and the main oil passage 14 can simultaneously supply oil to the rodless oil chamber 152 and the rod oil chamber 153 of the double-acting cylinder 15 through the first pipe 161, and in this state, the function of the double-acting cylinder 15 is equivalent to that of the single-acting cylinder 10, and the function of damping vibration can be well achieved. Meanwhile, the connection oil path 12 is communicated with the third pipeline 162, and the hydraulic oil in the third pipeline 162 flows into the connection oil path 12 after passing through the first cutoff valve 163, so that the synchronous adjustment of the double-acting cylinder 15 and the single-acting cylinder 10 can be realized. The main oil way 14 supplies oil to the single-acting oil cylinder 10 and the double-acting oil cylinder 15 simultaneously, so that the vehicle frame 2 can be lifted, and the height of the vehicle frame 2 can be adjusted conveniently.

In addition, with continued reference to fig. 2 in conjunction with fig. 5, when the first shutoff valve 163 is closed, the third line 162 is in a shut-off state, the first line 161 and the second line 160 are not communicated, and at this time, the main gallery 14 can supply oil to the rod oil chamber 153 of the double-acting cylinder 15 through the first line 161. The pressure of the rod oil cavity 153 is increased, the piston rod 151 of the double-acting oil cylinder 15 can be pushed to compress the hydraulic oil in the rodless oil cavity 152, the hydraulic oil in the rodless oil cavity 152 enters the single-cylinder oil way 11 or the energy accumulator assembly 13 through the connecting oil way 12 communicated with the third pipeline 162 after being compressed, and enters the single-acting oil cylinder 10 through the throttle valve of the first one-way throttle valve 110 on the single-cylinder oil way 11, so that the piston rod 102 of the single-acting oil cylinder 10 extends, the slow lifting of the whole vehicle frame 2 is realized, meanwhile, under the action of the hydraulic oil pressure in the rod oil cavity 153, the piston rod 151 of the double-acting oil cylinder 15 contracts, the vehicle axle 3 connected with the piston rod 151 is lifted, the contact quantity and the friction resistance between the wheels 5 on the vehicle axle 3 and the ground.

Referring to fig. 2 in combination with fig. 5, the connecting oil path 12 of the present invention is provided with a second check valve 121 and a second one-way throttle valve 120, and the hydraulic oil of the two-cylinder oil path 16 can flow into the connecting oil path 12 through the one-way valve in the second one-way throttle valve 120 and the second check valve 121, and flow into the single-cylinder oil path 11 and the accumulator assembly 13 through the connecting oil path 12. In the present embodiment, a second cut-off valve 121 and a second one-way throttle valve 120 are disposed between the connecting oil path 12 and the two-cylinder oil path 16, wherein the second cut-off valve 121 can control the on/off of the connecting oil path 12 and the two-cylinder oil path 16, and the second one-way throttle valve 120 can control the flow of the hydraulic oil between the connecting oil path 12 and the two-cylinder oil path 16.

Specifically, referring to fig. 2 in combination with fig. 5, when the second cut-off valve 121 is opened, the hydraulic oil in the two-cylinder oil passage 16 can rapidly flow into the connecting oil passage 12, the single-cylinder oil passage 11 and the accumulator assembly 13 through the check valve in the second check throttle valve 120 and the second cut-off valve 121. In this state, when the hydraulic oil pressure of the double-cylinder oil path 16 changes, the hydraulic oil can be quickly transmitted to the connecting oil path 12, the single-cylinder oil path 11 and the energy storage assembly 13 through the check valve in the second one-way throttle valve 120 and the second stop valve 121, so that the changed pressure is quickly absorbed by the energy storage assembly 13, and the buffering and vibration damping effects are well achieved. After the pressure of the hydraulic oil in the double-cylinder oil path 16 is balanced, the hydraulic oil in the connecting oil path 12 can slowly flow back to the double-cylinder oil path 16 through the throttle valves in the second stop valve 121 and the second one-way throttle valve 120, so that the changed pressure is attenuated, and the smooth operation of the vehicle is realized.

In addition, referring to fig. 2 in combination with fig. 5, when the second cut-off valve 121 is closed, the double-cylinder oil passage 16 is disconnected from the connecting oil passage 12, in this state, no matter the first cut-off valve 163 is opened or closed, the hydraulic oil pressure in the double-acting cylinder 15 and the double-cylinder oil passage 16 cannot be transmitted into the connecting oil passage 12, the double-acting cylinder 15 cannot transmit the hydraulic oil pressure to the accumulator assembly 13 through the double-cylinder oil passage 16 and the connecting oil passage 12, at this time, the double-acting cylinder 15 is rigidly locked, and the functions of damping and lifting the axle 3 cannot be realized. In addition, in this state, if the oil return path 18 is connected between the first cut-off valve 163 and the second cut-off valve 121, the double-acting cylinder 15 can be independently adjusted, and at this time, the extension and contraction of the piston rod 151 of the double-acting cylinder 15 can be realized through the active control of the main oil path 14, so that the axle 3 connected with the double-acting cylinder 15 is lifted or lowered, the number of the wheels 5 on the axle 3 contacting the ground and the frictional resistance are reduced, and the purposes of saving oil and reducing the wear of tires are achieved.

Referring to fig. 1 and 2 in combination with fig. 5, a third shut-off valve 122 is provided between the accumulator unit 13 and the connecting oil passage 12, and hydraulic oil in the connecting oil passage 12 can flow into the accumulator unit 13 through the third shut-off valve 122. In the present embodiment, a third stop valve 122 is provided between the accumulator unit 13 and the connection oil passage 12, and the third stop valve 122 can control the opening and closing of the accumulator unit 13 and the connection oil passage 12.

Specifically, referring to fig. 1 in combination with fig. 5, in the present embodiment, when the third cut-off valve 122 is opened, the connecting oil path 12 is communicated with the accumulator assembly 13, the main oil path 14 supplies oil to the single-acting cylinder 10 and the accumulator assembly 13 and then is closed, the single-acting cylinder 10 can transmit impact force to the accumulator assembly 13 through the single-cylinder oil path 11 and the connecting oil path 12, and the whole vehicle suspension system 1 can achieve the effect of buffering and damping vibration. When the third stop valve 122 is closed, the connecting oil path 12 is disconnected from the energy accumulator assembly 13, the single-acting oil cylinder 10 cannot transmit impact force to the energy accumulator assembly 13, and the single-acting oil cylinder 10 cannot achieve the functions of buffering and damping vibration and lifting the vehicle frame 2 because hydraulic oil cannot be compressed approximately, so that the whole vehicle suspension system 1 is equivalent to a rigid system, and the state is called rigid locking. In this state, the vehicle is suitable for loading and unloading goods, and the stability and safety of the vehicle body can be improved well.

In addition, referring to fig. 1 in combination with fig. 5, with the third cut-off valve 122 closed, the main oil passage 14 can supply oil to the single-acting cylinder 10 through the connecting oil passage 12 and the single-cylinder oil passage 11, so that the piston rod 102 of the single-acting cylinder 10 is extended, increasing the distance between the axle 3 and the vehicle frame 2, and raising the vehicle frame 2 as a whole. In addition, under the action of the gravity of the frame 2, the hydraulic oil in the single-acting cylinder 10 can also return to the oil tank 144 through the single-cylinder oil path 11, the connecting oil path 12 and the main oil path 14, so that the frame 2 is lowered integrally, and the lifting function of the whole frame 2 is realized. In addition, even in a state where the third stop valve 122 is open, the entire vehicle body frame 2 can be lifted and lowered by the main oil passage 14. In this case, the vehicle body frame 2 also has a function of buffering and damping vibration during the lifting process. However, the height of the vehicle frame 2 changes with the load of the vehicle frame 2, and this is suitable for reducing the height of the vehicle frame 2 through a culvert, a viaduct or changing the running height.

Referring to fig. 2 in combination with fig. 5, in the present embodiment, when the third cut-off valve 122 is opened, the connection oil path 12 is communicated with the accumulator assembly 13, and at this time, if the first cut-off valve 163 and the second cut-off valve 121 are both opened, in this state, the function of the double-acting cylinder 15 is equivalent to that of the single-acting cylinder 10, and the entire vehicle suspension system 1 can achieve the effect of shock absorption well. If the second stop valve 121 is closed, the double-cylinder oil path 16 is disconnected from the connecting oil path 12, the single-acting oil cylinder 10 can still be communicated with the energy accumulator assembly 13 through the single-cylinder oil path and the connecting oil path 12, and when the axle 3 connected with the single-acting oil cylinder 10 is impacted, the single-acting oil cylinder 10 can well achieve the effect of buffering and damping. With the second cut valve 121 closed, the double-acting cylinder 15 cannot transmit an impact force to the accumulator assembly 13 through the double cylinder oil passage 16 and the connecting oil passage 12 regardless of whether the first cut valve 163 is open or closed, at which time the double-acting cylinder 15 is rigidly locked. In this state, if the oil return path 18 is connected between the first cutoff valve 163 and the second cutoff valve 121, the double-acting cylinder 15 can be independently adjusted, and at this time, the extension and retraction of the piston rod 151 of the double-acting cylinder 15 can be realized by the active control of the main oil path 14, so that the axle 3 connected to the double-acting cylinder 15 is lifted or lowered, the number of the wheels 5 on the axle 3 contacting the ground and the frictional resistance are reduced, and the purposes of saving oil consumption and reducing tire wear are achieved.

Referring to fig. 2 in combination with fig. 5, in the present embodiment, when the third cut-off valve 122 is closed, the connecting oil passage 12 is disconnected from the accumulator assembly 13, and at this time, if the main oil passage 14 is not supplied with oil, the single-acting cylinder 10 and the double-acting cylinder 15 cannot transmit impact force to the accumulator assembly 13 regardless of whether the first cut-off valve 163 and the second cut-off valve 121 are opened or closed, and at this time, the entire vehicle suspension system 1 is rigidly locked. Under the condition, the vehicle is suitable for loading and unloading cargos, particularly large cargos, the height of the vehicle frame is prevented from changing along with the change of the load in the loading and unloading process, and the stability and the safety of the vehicle can be well improved.

In addition, referring to fig. 2 in combination with fig. 5, in the case that the third cut-off valve 122 is closed, if the main oil path 14 supplies oil, the first cut-off valve 163 and the second cut-off valve 121 are simultaneously opened, at this time, the function of the double-acting cylinder 15 is equal to that of the single-acting cylinder 10, and the main oil path 14 simultaneously supplies oil to the single-acting cylinder 10 and the double-acting cylinder 15, so that the lifting of the vehicle frame 2 can be realized, and the height of the vehicle frame 2 can be conveniently adjusted.

Further, referring to fig. 2 in combination with fig. 5, in the case where the third cut-off valve 122 is closed, if the main oil passage 14 supplies oil, the first cut-off valve 163 and the second cut-off valve 121 are closed at the same time, at this time, the pressure supplied from the main oil passage 14 cannot be transmitted to the single-acting cylinder 10, the single-acting cylinder 10 is in a rigidly locked state, the pressure supplied from the main oil passage 14 enters the rod oil chamber 153 of the double-acting cylinder 15, so that the hydraulic oil in the rodless oil chamber 152 of the double-acting cylinder 15 is compressed, and the pressure increases, and since the second cut-off valve 121 is closed at this time, the pressure in the rodless oil chamber 152 of the double-acting cylinder 15 cannot be transmitted, and in this state, if the main oil passage 14 continues to supply oil, the pressure in the rodless oil chamber 152 of the double-acting cylinder 15 continues to increase, which may cause. At this time, if the oil return path 18 is connected between the first cut-off valve 163 and the second cut-off valve 121, the rodless oil chamber 152 of the double-acting cylinder 15 can return to the oil tank 144 through the oil return path 18, and the piston rod 151 of the double-acting cylinder 15 retracts into the cylinder body 150 of the double-acting cylinder 15, so that the axle 3 connected to the double-acting cylinder 15 is lifted, the number of wheels 5 on the axle 3 contacting the ground and the frictional resistance are reduced, and the purposes of saving oil and reducing tire wear are achieved.

Further, referring to fig. 2 in combination with fig. 5, in the case that the third cut-off valve 122 is closed, if the main oil path 14 supplies oil, the first cut-off valve 163 is opened, the second cut-off valve 121 is closed, at this time, the pressure supplied by the main oil path 14 cannot be transmitted to the single-acting cylinder 10, the single-acting cylinder 10 is in a rigidly locked state, the first cut-off valve 163 is opened, the function of the double-acting cylinder 15 is equal to that of the single-acting cylinder 10, the main oil path 14 supplies oil to the double-acting cylinder 15, so that the piston rod 151 of the double-acting cylinder 15 extends, and the lifting of a part of the frame 2 connected with the double-acting cylinder 15 can.

Further, referring to fig. 2 in conjunction with fig. 5, in the case where the third cut-off valve 122 is closed, if the main line 14 is supplied with oil, the first cut-off valve 163 is closed, and the second cut-off valve 121 is opened, at which time, the pressure supplied from the main line 14 enters the rod oil chamber 153 of the double-acting cylinder 15, so that the pressure of the hydraulic oil in the rodless oil chamber 152 of the double-acting cylinder 15 is increased, the pressure in the rodless oil chamber 152 of the double-acting cylinder 15 is transmitted to the single-acting cylinder 10 through the second line 160, the third line 162, the connecting oil passage 12, and the single-cylinder oil passage 11, so that the piston rod 102 of the single-acting cylinder 10 is extended and the piston rod 151 of the double-acting cylinder 15 is retracted, in which case, the distance between the axle 3, which is connected to the piston rod 102, and the vehicle frame 2 is increased, so that the vehicle frame 2 is raised as a whole, at the same time, the distance between the axle 3 connected with the piston rod 151 and the vehicle frame 2 is reduced, so that the axle 3 connected with the piston rod 151 is lifted.

Referring to fig. 1-3 in conjunction with fig. 5, the accumulator assembly 13 of the present invention includes a high pressure accumulator 130 and a low pressure accumulator 131, the high pressure accumulator 130 communicating with the low pressure accumulator 131. In the present embodiment, the accumulator assembly 13 includes a high pressure accumulator 130 and a low pressure accumulator 131, the high pressure accumulator 130 is communicated with the low pressure accumulator 131, wherein the low pressure accumulator 131 and the high pressure accumulator 130 are respectively filled with nitrogen gas with different pressures, and the nitrogen gas is used as a buffer medium of the vehicle suspension system 1, and is equivalent to the action of a spring, and can well absorb impact force and vibration transmitted from each oil path.

The vehicle suspension system 1 of the embodiment adopts two-stage energy accumulators with different pressures as buffering media, and can adapt to the impact on the vehicle suspension system 1 under different load conditions. When the axle 3 is impacted, the high-pressure energy accumulator 130 and the low-pressure energy accumulator 131 participate in the buffering and vibration reduction effects according to the load condition, active adjustment is not needed, and adaptive adjustment of empty and full load can be achieved.

Specifically, referring to fig. 1 to 3 in combination with fig. 5, in the present embodiment, the low pressure accumulator 131 and the high pressure accumulator 130 are respectively filled with nitrogen gas at different pressures, and the pressure of the nitrogen gas filled in the low pressure accumulator 131 is smaller than that of the nitrogen gas filled in the high pressure accumulator 130, that is, the opening pressure of the low pressure accumulator 131 is smaller than that of the high pressure accumulator 130. Under the condition of no load or light load, the pressure of the vehicle frame 2 on the vehicle suspension system 1 is smaller, at the moment, if the axle 3 is impacted, the single-acting oil cylinder 10 or the double-acting oil cylinder 15 can transmit the impact force into the low-pressure energy accumulator 131 and the high-pressure energy accumulator 130 through the connecting oil way 12, because the opening pressure of the low-pressure energy accumulator 131 is smaller than the opening pressure of the high-pressure energy accumulator 130, the pressure generated by the impact force and the gravity of the vehicle frame 2 can open the low-pressure energy accumulator 131 to compress nitrogen in the low-pressure energy accumulator 131, so that the vibration generated by the impact force is absorbed, and a good buffering and vibration reduction effect is realized.

In addition, referring to fig. 1 to fig. 3 in combination with fig. 5, in this embodiment, when the load of the frame 2 reaches a certain critical value, for example, when the frame 2 is loaded with goods or is fully loaded, the pressure and impact force borne by the double-acting cylinder 15 or the single-acting cylinder 10 may greatly change, the low-pressure accumulator 131 and the high-pressure accumulator 130 may both be opened due to the changed impact force and the pressure generated by the gravity of the frame 2, the low-pressure accumulator 131 and the high-pressure accumulator 130 participate in the process of damping, and the nitrogen in the low-pressure accumulator 131 and the nitrogen in the high-pressure accumulator 130 may both be compressed, so as to effectively absorb the vibration generated by the impact force, and achieve a good damping effect. In general, the energy accumulator assembly 13 of the present invention adopts a two-stage pressure type structure composed of a low-pressure energy accumulator 131 and a high-pressure energy accumulator 130, and can adapt to the working conditions with large load range variation, and realize the self-adaptive function of large-scale buffer span and empty/full load, and the vehicle suspension system 1 has good buffer and vibration reduction effects under different load conditions.

Referring to fig. 1 to 3, a vehicle suspension system 1 provided by the present invention includes a main oil path 14, a safety oil path 17, and an oil return path 18, where the main oil path 14, the safety oil path 17, and the oil return path 18 in the vehicle suspension system 1 provided by the present invention are substantially the same as those in a hydraulic system in the prior art, the main oil path 14 mainly provides hydraulic oil for other oil paths, the safety oil path 17 is used to perform a safety protection function when a system pressure is too high, so that redundant hydraulic oil overflows back to an oil tank 144, safety of each oil path is ensured, and the oil return path 18 enables hydraulic oil in each oil path to return to the oil tank 144.

Specifically, as shown in fig. 1 to 3, the main oil passage 14 of the present invention includes a filter 140, a pump 141, a main check valve 142, a main stop valve 143, and an oil tank 144, and when oil is supplied, hydraulic oil in the oil tank 144 is sucked by the pump 141 after passing through the filter 140, the pump 141 can discharge the sucked hydraulic oil, and hydraulic oil discharged from the pump 141 can flow into another oil passage from the main oil passage 14 after passing through the main check valve 142 and the main stop valve 143. Referring to fig. 1, in the present embodiment, the hydraulic oil discharged from the pump 141 can flow from the main oil passage 14 into the connecting oil passage 12 after passing through the main check valve 142 and the main stop valve 143. Referring to fig. 2 and 3, in the present embodiment, the hydraulic oil discharged from the pump 141 can flow from the main oil passage 14 into the two-cylinder oil passage 16 after passing through the main check valve 142 and the main cut valve 143.

Referring to fig. 1 to 3, the relief oil passage 17 of the present embodiment is provided with a relief valve 170, and the hydraulic oil flowing out of the pump 141 can flow into the relief oil passage 17, pass through the relief valve 170, and then return to the oil tank 144. The oil return path 18 in this embodiment is communicated with the main oil path 14, and the oil return path 18 is provided with an oil return stop valve 180, so that when the system supplies oil, the hydraulic oil flowing out of the pump 141 can enter the oil return path 18 after passing through the main check valve 142, and then returns to the oil tank 144 after passing through the oil return stop valve 180; during system oil return, the hydraulic oil outside the main oil passage 14 can flow into the main oil passage 14, flow through the main stop valve 143, flow into the return oil passage 18, pass through the return stop valve 180, and return to the tank 144. In other embodiments, the oil return path 18 is communicated with other oil paths, as long as the hydraulic oil in each oil path can smoothly return to the oil tank 144 in the oil return process.

Referring to fig. 3, the vehicle suspension system 1 of the present invention further includes a direction control oil passage 19, the direction control oil passage 19 is respectively communicated with the two-cylinder oil passage 16 and the main oil passage 14, and the direction control oil passage 19 is provided with a direction valve 190. In this embodiment, the reversing control oil path 19 is respectively communicated with the double-cylinder oil path 16 and the main oil path 14, and the change of the flow direction of the hydraulic oil entering the double-cylinder oil path 16 can be realized by changing the state of the reversing valve 190, so that the control process is simple and the operation is convenient.

Referring to fig. 3 and 4, the reversing valve 190 of the present embodiment is a three-position four-way reversing valve, the spool performance code of the reversing valve 190 is P, the port a of the reversing valve 190 is communicated with the second pipeline 160, the port B of the reversing valve 190 is communicated with the first pipeline 161, the port T of the reversing valve 190 is communicated with the main oil passage 14, the port P of the reversing valve 190 is communicated with the oil tank 144, and hydraulic oil flowing out of the pump 141 can flow into the reversing valve 190 through the port T of the reversing valve 190 after flowing through the main one-way valve 142, and can flow into the double-cylinder oil passage 16 through the port a or the port B of the reversing valve 190.

Referring to fig. 3 and 4, a hydraulic lock 191 is provided between the directional valve 190 and the two-cylinder oil path 16 in the present embodiment. By arranging the hydraulic lock 191 between the reversing valve 190 and the double-cylinder oil path 16, under the state that the hydraulic lock 191 is locked, hydraulic oil in other oil paths can be reliably prevented from leaking into the reversing valve 190, and the working pressure and safety in each oil path are ensured. When oil is supplied to other oil paths through the reversing valve 190, the hydraulic lock 191 is opened, so that hydraulic oil in the reversing valve 190 can smoothly enter the other oil paths, and hydraulic oil in the other oil paths can smoothly enter the reversing valve 190 through the hydraulic lock 191 and return to the oil tank 144 through the reversing valve 190.

Specifically, referring to fig. 3 and 4, the direction valve 190 in this embodiment is a three-position four-way direction valve with a spool performance code P, the port a of the direction valve 190 is communicated with the second pipeline 160, the port B of the direction valve 190 is communicated with the first pipeline 161, the port T of the direction valve 190 is communicated with the main oil passage 14, and the port P of the direction valve 190 is communicated with the oil tank 144, wherein when the spool of the direction valve 190 is at the neutral position, the port T of the direction valve 190 is closed, and hydraulic oil in other oil passages can return to the oil tank from the port P of the direction valve 190 through the port a and the port B of the direction valve 190. Referring to fig. 3 and 4, in the present embodiment, a hydraulic lock 191 is disposed between the directional valve 190 and the two-cylinder oil path 16, and the hydraulic lock 191 prevents hydraulic oil in another oil path from returning to the oil tank from the port P of the directional valve 190 through the ports a and B of the directional valve 190, so that working pressure and safety in another oil path can be ensured when the port T of the directional valve 190 is closed.

Further, referring to fig. 3 and 4 in combination with fig. 5, when the spool of the directional valve 190 is in the left position, the hydraulic oil flowing out of the pump 141 can flow into the directional valve 190 from the T port of the directional valve 190 after flowing through the main check valve 142, and flow out from the B port of the directional valve 190, the hydraulic oil flowing out from the B port of the directional valve 190 acts on the hydraulic lock 191, the hydraulic lock 191 is opened, so that the hydraulic oil flowing out from the B port of the directional valve 190 can flow into other oil paths, and the hydraulic oil in the other oil paths can also return to the oil tank through the a port and the P port of the directional valve 190. Referring to fig. 3 and 4, in the present embodiment, the port a of the direction switching valve 190 is connected to the connection between the connection oil path 12 and the third pipeline 162, which corresponds to the connection between the connection oil path 12 and the third pipeline 162 being connected to an oil return passage, the port B of the direction switching valve 190 is connected to the connection between the main oil path 14 and the first pipeline 161, and the pump 141 can supply oil to the first pipeline 161 through the ports T and B of the direction switching valve 190. At this time, the main stop valve 143 is closed, and the hydraulic oil supplied from the pump 141 can enter the first pipeline 161 through the T port and the B port of the directional control valve 190, in this case, if the first stop valve 163 is closed, the hydraulic oil supplied from the pump 141 can enter the rod oil chamber 153 of the double-acting cylinder 15 through the T port and the B port of the directional control valve 190, so that the hydraulic oil in the rod-less oil chamber 152 of the double-acting cylinder 15 is compressed and the pressure is increased, and at this time, the hydraulic oil in the rod-less oil chamber 152 of the double-acting cylinder 15 can return to the oil tank through the a port and the P port of the directional control valve 190, the piston rod 151 of the double-acting cylinder 15 retracts. When the first cut valve 163 is opened, the hydraulic oil supplied from the pump 141 passes through the ports T and B of the direction valve 190, and then flows directly from the first cut valve 163 into the ports a and P of the direction valve 190 to return to the tank. Therefore, when the spool of the direction switching valve 190 is in the left position, the master cut valve 143 is closed, and the pressure supplied from the pump 141 can retract only the piston rod 151 of the double-acting cylinder 15 regardless of the state of the other valves, and the axle 3 connected to the piston rod 151 is lifted.

Further, referring to fig. 3 and 4 in combination with fig. 5, when the spool of the directional valve 190 is in the right position, the hydraulic oil flowing out of the pump 141 can flow into the directional valve 190 from the T port of the directional valve 190 after flowing through the main check valve 142, and can flow out through the a port of the directional valve 190, and the hydraulic oil flowing out of the a port of the directional valve 190 acts on the hydraulic lock 191, so that the hydraulic lock 191 is opened, and the hydraulic oil flowing out of the a port of the directional valve 190 can flow into other oil paths, and the hydraulic oil in the other oil paths can also return to the oil tank through the B port and the P port of the directional valve 190.

Specifically, referring to fig. 3 and 4, in the present embodiment, when the spool of the direction valve 190 is in the right position, the port B of the direction valve 190 is connected to the connection between the main oil passage 14 and the first pipeline 161, which is equivalent to that an oil return passage is connected to the connection between the main oil passage 14 and the first pipeline 161, the port a of the direction valve 190 is connected to the connection between the connecting circuit 12 and the third pipeline 162, and the pump 141 can supply oil to the third pipeline 161 through the port T and the port a of the direction valve 190. At this time, the main stop valve 143 is closed, the hydraulic oil supplied from the pump 141 can enter the third pipeline 161 through the T port and the a port of the directional valve 190, if the first stop valve 163 is closed, the hydraulic oil supplied from the pump 141 can enter the rodless oil chamber 152 of the double-acting cylinder 15 of the connecting oil path through the T port and the a port of the directional valve 190, the hydraulic oil in the rod oil chamber 153 of the double-acting cylinder 15 is compressed, the pressure in the rod oil chamber 153 is increased, the hydraulic oil in the rod oil chamber 153 of the double-acting cylinder 15 can return to the oil tank through the B port and the P port of the directional valve 190, the piston rod 151 of the double-acting cylinder 15 extends, and the original lifted axle 3 can be restored to.

Referring to fig. 3 and 4, when the spool of the directional control valve 190 is in the right position, if the second stop valve 121 and the third stop valve 122 are opened simultaneously, the first stop valve 163 and the main stop valve 143 are closed simultaneously, the hydraulic oil supplied by the pump 141 can enter the single-acting cylinder 10 through the connecting oil passage 12 while entering the third pipeline 161 through the T port and the a port of the directional control valve 190, so that the piston rod 102 of the single-acting cylinder 10 and the piston rod 151 of the double-acting cylinder 15 are extended simultaneously, the frame 2 is raised integrally, and the frame 2 also has a damping function during the raising process. However, the height of the vehicle frame 2 changes with the load of the vehicle frame 2, and this is suitable for reducing the height of the vehicle frame 2 through the culvert and the viaduct, or changing the running height.

Referring to fig. 3 and 4, when the spool of the directional control valve 190 is in the right position, if the second cut-off valve 121 is opened and the third cut-off valve 122 is closed, the first cut-off valve 163 and the main cut-off valve 143 are closed at the same time, the hydraulic oil supplied by the pump 141 can enter the single-acting cylinder 10 through the connecting oil passage 12 while entering the third pipeline 161 through the T port and the a port of the directional control valve 190, so that the piston rod 102 of the single-acting cylinder 10 and the piston rod 151 of the double-acting cylinder 15 are extended at the same time, and the frame 2 is raised as a whole. At this time, the accumulator unit 13 is disconnected from the connection oil passage 12, and the vehicle suspension system 1 cannot achieve the function of damping vibration.

Referring to fig. 3 and 4, when the spool of the direction switching valve 190 is in the right position, if the second cut valve 121 is closed and the third cut valve 122 is opened, the first cut valve 163 and the main cut valve 143 are closed at the same time, and the hydraulic oil supplied from the pump 141 cannot enter the single-acting cylinder 10 through the connecting oil passage 12. At this time, the accumulator unit 13 communicates with the connecting oil passage 12, and the single-acting cylinder 10 has a function of damping vibration. If the third cut-off valve 122 is also closed, the accumulator unit 13 is disconnected from the connecting oil passage 12, the single-acting cylinder 10 cannot transmit the impact force to the accumulator unit 13, and the single-acting cylinder 10 is in a rigid lock state. In addition, when the second stop valve 121, the first stop valve 163 and the main stop valve 143 are closed at the same time, no matter whether the third stop valve 122 is opened or closed, the hydraulic oil supplied from the pump 141 can enter the third pipeline 161 through the T port and the a port of the directional valve 190, so that the hydraulic oil in the rod oil chamber 153 of the double-acting cylinder 15 is compressed, the pressure is increased, the hydraulic oil in the rod oil chamber 153 of the double-acting cylinder 15 can return to the oil tank through the B port and the P port of the directional valve 190, the piston rod 151 of the double-acting cylinder 15 extends, and the original lifted axle 3 can be brought back into contact with the ground.

It should be noted that referring to fig. 5 in conjunction with fig. 1 to 3, in order to simplify the oil passages for easy installation, the various control valves and the connecting oil passages 12 of the present invention are integrated on a manifold block 6. The present invention is not limited as to how the various control valves and the connecting oil passages 12 are provided in the manifold block 6, as long as the functions of the various control valves and the connecting oil passages 12 in the present invention can be achieved. Specifically, the various control valves of the present invention include a first cut-off valve 163, a second cut-off valve 121, a third cut-off valve 122, a first one-way throttle valve 110, a second one-way throttle valve 120, a main check valve 142, a main cut-off valve 143, an overflow valve 170, a return cut-off valve 180, a selector valve 190, and a hydraulic lock 191.

Referring to fig. 1-3 in conjunction with fig. 5, the single-acting cylinder 10 of the present invention is a single-acting hydro-pneumatic spring cylinder and the double-acting cylinder 15 is a double-acting hydro-pneumatic spring cylinder. In this embodiment, hydro-pneumatic spring cylinder not only has buffering, damping, goes up and down in a great deal of functions of an organic whole, still has compact structure, integrates advantages such as degree height, is the novel product that oil gas combines. In this embodiment, the single-acting oil cylinder 10 is a single-acting hydro-pneumatic spring cylinder, and the single-acting hydro-pneumatic spring cylinder only needs to be driven by hydraulic oil in one direction, can be restored to a compressed state by self weight or external force, and is simple in structure and convenient to control and install. Referring to fig. 2 and 3 in combination with fig. 5, in this embodiment, the double-acting oil cylinder 15 is a double-acting hydro-pneumatic spring cylinder, which not only can achieve the effect of buffering and damping, but also can achieve the extension and contraction of a piston rod of the double-acting hydro-pneumatic spring cylinder through active control, so as to actively achieve the lifting and lowering of an axle, and the control process is simple and convenient to use.

Referring to fig. 5 in combination with fig. 1 to 3, the vehicle suspension system 1 of the present invention further includes a connecting arm 4, the single-acting cylinder 10 and the double-acting cylinder 15 are both connected to the axle 3 through the connecting arm 4, one end of the connecting arm 4 is hinged to the frame 2, the other end of the connecting arm 4 is hinged to the piston rod 102 of the single-acting cylinder 10 and the piston rod 151 of the double-acting cylinder 15, respectively, the cylinder body 100 of the single-acting cylinder 10 and the cylinder body 150 of the double-acting cylinder 15 are both hinged to the frame 2, and the axle 3 is disposed on the connecting arm 4 along the width direction of the. In this embodiment, the single-acting cylinder 10 is connected to the axle 3 through the connecting arm 4, the frame 2 is provided with a connecting bracket 20 and a hinge bracket 21, one end of the connecting arm 4 is hinged to the connecting bracket 20 on the frame 2, the other end is hinged to the piston rod 102 of the single-acting cylinder 10 and the piston rod 151 of the double-acting cylinder 15, the cylinder body 100 of the single-acting cylinder 10 and the cylinder body 150 of the double-acting cylinder 15 are both hinged to the hinge bracket 21 on the frame 2, and the axle 3 is arranged on the connecting arm 4 along the width direction of the frame 2.

As described above, in the vehicle suspension system 1 according to the present invention, the single-acting cylinder 10 is used to replace a double-acting cylinder in the prior art, which not only simplifies the structure of the cylinder and reduces the cost, but also the single-acting cylinder 10 only needs to be hydraulically driven in a single direction, and can be restored to a compressed state by the gravity of the vehicle frame 2, which simplifies the control oil path and the connection oil path 12, so that the control valve assembly and the control process are simpler and are convenient to control and install. In addition, the energy accumulator component 13 of the present invention adopts a two-stage pressure type structure composed of a low-pressure energy accumulator 131 and a high-pressure energy accumulator 130, which can adapt to the working conditions with large load range variation, and realize the self-adapting function of large-scale buffer span and empty-full load, and the vehicle suspension system 1 has good buffer and vibration damping effects under the conditions of no load, light load, heavy load and full load. The vehicle suspension system 1 with the single-acting oil cylinder 10 is used for replacing a traditional air suspension, rigid locking and quick response of the whole vehicle suspension system 1 can be realized, a vehicle is safer and more stable when stopped, and the whole lifting of the vehicle frame 2 can be realized by controlling the pressure in the oil cavity 101 of the single-acting oil cylinder 10. In addition, the invention also combines and uses the double-acting oil cylinder 15 to lift part of the axle 3, and reduces the contact quantity of the wheels 5 on the axle 3 and the ground, thereby achieving the purposes of saving oil consumption and reducing tire wear.

In summary, compared with the conventional air suspension, the vehicle suspension system 1 provided by the invention has the advantages of fast response, higher safety and stability, capability of realizing empty and full load self-adaptation and the like, and compared with a suspension system which totally uses a double-acting oil cylinder as a suspension support in the prior art, the vehicle suspension system 1 has the advantages of simple structure, convenience in control, lower cost, convenience in installation and the like, and meanwhile, the energy accumulator assembly 13 with a two-stage pressure type structure is used, so that the vehicle suspension system 1 has a good buffering and vibration damping effect and better smoothness.

In summary, the above-mentioned embodiments are provided only for illustrating the principles and effects of the present invention, and not for limiting the present invention. Any person skilled in the art can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present invention. Accordingly, it is intended that all equivalent modifications or changes which can be made by those skilled in the art without departing from the spirit and technical spirit of the present invention be covered by the claims of the present invention.

Claims

1. A vehicle suspension system disposed between a vehicle frame and an axle, comprising:

the single-acting oil cylinder is respectively connected with the frame and the axle and can form elastic support between the frame and the axle;

a single cylinder oil path communicated with the oil chamber of the single-acting cylinder,

also comprises a connecting oil path, an energy accumulator component and a main oil path, wherein,

the main oil way is communicated with the single-cylinder oil way and the energy accumulator assembly through the connecting oil way, and hydraulic oil of the main oil way can sequentially flow through the connecting oil way and the single-cylinder oil way to enter an oil cavity of the single-acting oil cylinder.

2. The vehicle suspension system according to claim 1, wherein a first one-way throttle valve is provided on the single-cylinder oil passage, and hydraulic oil in the single-acting cylinder can flow into the connecting oil passage through a one-way valve in the first one-way throttle valve.

3. The vehicle suspension system of claim 1, further comprising:

the double-acting oil cylinder is respectively connected with the frame and the axle and can form elastic support between the frame and the axle;

the double-cylinder oil way is respectively communicated with the connecting oil way and the main oil way, and hydraulic oil of the main oil way can enter the double-cylinder oil way and the connecting oil way.

4. The vehicle suspension system of claim 3, wherein said dual cylinder oil circuit comprises:

the first pipeline is used for communicating rod oil chambers of the pair of double-acting oil cylinders;

the second pipeline is used for communicating rodless oil chambers of the pair of double-acting oil cylinders;

and the third pipeline is used for communicating the first pipeline and the second pipeline.

5. The vehicle suspension system according to claim 4, wherein a first shut-off valve is provided on said third line, and the hydraulic oil in said first line can flow into said second line after passing through said first shut-off valve on said third line.

6. The vehicle suspension system according to claim 5, wherein the connection oil passage communicates with the third line, and the hydraulic oil of the first line can flow into the connection oil passage through the first shut-off valve after flowing into the third line.

7. The vehicle suspension system according to claim 6, wherein a second check valve and a second check throttle valve are provided on the connection oil path, and the hydraulic oil of the two-cylinder oil path is allowed to flow into the connection oil path through a check valve in the second check throttle valve and the second check valve, and to flow into the single-cylinder oil path and the accumulator assembly through the connection oil path.

8. The vehicle suspension system according to claim 1, wherein a third shut-off valve is provided between the accumulator assembly and the connecting oil passage, and hydraulic oil in the connecting oil passage can flow into the accumulator assembly through the third shut-off valve.

9. The vehicle suspension system of claim 8 wherein said accumulator assembly includes a high pressure accumulator and a low pressure accumulator, said high pressure accumulator being in communication with said low pressure accumulator.

10. The vehicle suspension system according to claim 1, wherein the main oil passage includes a filter, a pump, a main check valve, a main stop valve, and a tank, and when the oil is supplied, the hydraulic oil in the tank is sucked by the pump after passing through the filter, the pump is capable of discharging the sucked hydraulic oil, and the hydraulic oil discharged from the pump is capable of flowing from the main oil passage into the connection oil passage after passing through the main check valve and the main stop valve.

11. The vehicle suspension system according to claim 4, wherein the main oil passage includes a filter, a pump, a main check valve, a main stop valve, and a tank, and when the oil is supplied, the hydraulic oil in the tank is sucked by the pump after passing through the filter, the pump is capable of discharging the sucked hydraulic oil, and the hydraulic oil discharged from the pump is capable of flowing from the main oil passage into the two-cylinder oil passage after passing through the main check valve and the main stop valve.

12. The vehicle suspension system according to claim 10 or 11, further comprising a relief oil passage provided with a relief valve, wherein the hydraulic oil flowing out from the pump can flow into the relief oil passage and return to the oil tank after passing through the relief valve.

13. The vehicle suspension system according to claim 10 or 11, further comprising an oil return passage communicating with said main oil passage, said oil return passage being provided with an oil return shutoff valve,

when the system supplies oil, the hydraulic oil flowing out of the pump can enter the oil return oil way after passing through the main check valve and then return to the oil tank after passing through the oil return stop valve;

when the system returns oil, hydraulic oil outside the main oil way can flow into the main oil way, can flow into the oil return oil way after flowing through the main stop valve, and returns to the oil tank after passing through the oil return stop valve.

14. The vehicle suspension system according to claim 11 further comprising a directional control oil passage in communication with said dual cylinder oil passage and said main oil passage, respectively, said directional control oil passage being provided with a directional valve.

15. The vehicle suspension system according to claim 14 wherein said directional control valve is a three-position, four-way directional control valve having a spool performance designation P, said port a of said directional control valve being in communication with said second line, said port B of said directional control valve being in communication with said first line, said port T of said directional control valve being in communication with said main oil passage, said port P of said directional control valve being in communication with an oil tank, hydraulic oil from said pump being able to flow through said port T of said directional control valve into said directional control valve after flowing through said main check valve and through either port a or port B of said directional control valve into said two-cylinder oil passage.

16. A vehicle suspension system according to claim 14 or 15 wherein a hydraulic lock is provided between the directional valve and the dual cylinder oil circuit.

17. The vehicle suspension system of claim 1 wherein said single-acting cylinder is a single-acting hydro-pneumatic spring cylinder.

18. A vehicle suspension system according to claim 3 wherein said single acting cylinder is a single acting hydro-pneumatic spring cylinder and said double acting cylinder is a double acting hydro-pneumatic spring cylinder.

19. The vehicle suspension system according to claim 1, further comprising a connecting arm through which said single-acting cylinder is connected to said axle, said connecting arm being hinged at one end to said frame and at the other end to a piston rod of said single-acting cylinder, a cylinder body of said single-acting cylinder being hinged to said frame, said axle being provided on said connecting arm in a width direction of said frame.

20. The vehicle suspension system according to claim 3, further comprising a connecting arm through which both the single-acting cylinder and the double-acting cylinder are connected to the axle, one end of the connecting arm being hinged to the frame, the other end of the connecting arm being hinged to a piston rod of the single-acting cylinder and a piston rod of the double-acting cylinder, respectively, a cylinder body of the single-acting cylinder and a cylinder body of the double-acting cylinder being hinged to the frame, the axle being provided on the connecting arm in a width direction of the frame.