Double-speed steering system and steering method

Abstract

The system comprises an oil tank, an oil pump, an electromagnetic valve, a steering gear, a first oil cylinder, a second oil cylinder and a flow amplifying valve, the oil pump extracts hydraulic oil from the oil tank and provides pressure oil through an oil outlet of the oil pump, and the electromagnetic valve is provided with a first electromagnetic valve position and a second electromagnetic valve position and used for switching oil paths. The steering gear is provided with an oil inlet, an oil return port, an oil supply port L and an oil supply port R, oil liquid is distributed according to a steering instruction, when the electromagnetic valve is closed, the first oil cylinder small cavity and the second oil cylinder large cavity are controlled to obtain oil or the first oil cylinder large cavity and the second oil cylinder small cavity are controlled to obtain oil, and when the reversing valve is switched, the oil return port is opened. The oil way used for reversing of the reversing valve can be used for supplementing power to the oil cylinders and achieving rapid rotation, when the electromagnetic valve is powered on, hydraulic oil bypasses the flow amplifying valve and directly enters the first oil cylinder large cavity or the second oil cylinder large cavity, slow steering operation is completed, and the applicability and economical efficiency of a steering system are improved by integrating the rapid steering effect and the slow steering effect.

Description

Technical Field

[0001] The present invention relates to the technical field of engineering machinery, and in particular to a dual-speed steering system and a steering method. Background Art

[0002] At present, the steering system of loaders mainly relies on large-displacement steering gear steering system and flow amplification valve steering system. Both systems adopt the design of supplying oil to two cylinders at the same time, ensuring the stability and power output of the loader during steering. The large-displacement steering gear directly uses a large-displacement pump to provide sufficient flow, while the flow amplification valve system controls the output of large flow through a small pilot flow to achieve steering operation.

[0003] During operation, loaders have different requirements for steering speed. In scenarios that require fast steering, such as emergency obstacle avoidance or rapid adjustment of the operating position, the loader needs to be able to respond to operating instructions quickly and sensitively to improve operating efficiency. In some situations that require delicate operations, such as operations in narrow spaces, the loader requires slow and precise steering to ensure the safety and accuracy of the operation. Therefore, the steering system of the loader needs to take into account both the sensitivity of fast steering and the accuracy of slow steering.

[0004] However, the current loader steering system has certain shortcomings in both fast and slow steering. In fast steering, the need to provide a large flow to both cylinders at the same time leads to a significant increase in energy consumption, and the steering accuracy is often difficult to accurately grasp. In slow steering, although energy consumption is reduced and steering accuracy is improved, the steering speed is too slow and may not meet the efficiency requirements of certain operating scenarios. Summary of the invention

[0005] In order to overcome at least one defect of the prior art described above, the present invention provides a dual-speed steering system and a steering method, which can solve the problem of low applicability caused by the loader not having two steering systems, namely, fast steering and slow steering.

[0006] The technical solution adopted by the present invention to solve the problem is:

[0007] A dual-speed steering system, comprising:

[0008] tank;

[0009] An oil pump, the oil pump having an oil pump inlet and an oil pump outlet, the oil pump inlet being connected to the oil tank;

[0010] A solenoid valve having a first solenoid valve position and a second solenoid valve position;

[0011] A steering gear, the steering gear having a steering gear oil inlet, a steering gear oil return port, a steering gear L oil supply port and a steering gear R oil supply port, the steering gear oil return port being in communication with the oil tank;

[0012] A first oil cylinder, the first oil cylinder having a first oil cylinder large chamber and a first oil cylinder small chamber;

[0013] A second oil cylinder, the second oil cylinder having a second oil cylinder large cavity and a second oil cylinder small cavity;

[0014] A flow amplifying valve, wherein the flow amplifying valve has a reversing valve, a first flow amplifying oil outlet and a second flow amplifying oil outlet, the reversing valve has a first reversing valve position, a second reversing valve position and a third reversing valve position, the oil pump outlet is connected to the reversing valve, and the oil circuit from the steering gear R oil supply port to the reversing valve is provided with two interfaces, one of which is used to connect the reversing valve so that the reversing valve is switched to the first reversing valve position, and the other interface is connected to the middle part of the reversing valve so that when the reversing valve is switched to the first reversing valve position, the hydraulic oil of the interface flows through the reversing valve and enters the first oil cylinder large cavity and the The second oil cylinder small chamber, the oil circuit from the oil supply port of the steering gear L to the reversing valve is provided with two interfaces, one of which is used to connect the reversing valve, so that the reversing valve is switched to the third reversing valve position, and the other interface is connected to the middle part of the reversing valve, so that when the reversing valve is switched to the third reversing valve position, the hydraulic oil of the interface flows through the reversing valve and enters the first oil cylinder small chamber and the second oil cylinder large chamber. The second reversing valve position of the reversing valve is the valve position when the reversing valve is not subjected to the reversing power. When the reversing valve is in the second reversing valve position, the reversing valve cuts off the oil pump outlet to flow through the reversing valve;

[0015] When the solenoid valve is in the first solenoid valve position, the oil outlet of the oil pump is connected with the oil inlet of the steering gear. When the steering gear is adjusted to the point where the oil inlet of the steering gear is connected with the oil supply port of the steering gear R, the hydraulic oil pumped by the oil outlet of the oil pump flows in through the oil supply port of the steering gear R and enters one side of the reversing valve, switching the reversing valve to the first reversing valve position. When the reversing valve is in the first reversing valve position, the reversing valve converts the hydraulic oil supplied by the oil outlet of the oil pump and the hydraulic oil used for the reversing oil circuit of the reversing valve to the first flow amplification oil outlet and transmits them to the large chamber of the first oil cylinder and the small chamber of the second oil cylinder;

[0016] When the solenoid valve is in the first solenoid valve position, the oil outlet of the oil pump is connected with the oil inlet of the steering gear. When the steering gear is adjusted to the point where the oil inlet of the steering gear is connected with the oil supply port L of the steering gear, the hydraulic oil pumped by the oil outlet of the oil pump flows in through the oil supply port L of the steering gear and enters the other side of the reversing valve, switching the reversing valve to the third reversing valve position. When the reversing valve is in the third reversing valve position, the reversing valve converts the hydraulic oil supplied by the oil outlet of the oil pump and the hydraulic oil used for the reversing oil circuit of the reversing valve to the second flow amplification oil outlet, and transmits them to the first oil cylinder small chamber and the second oil cylinder large chamber.

[0017] When the solenoid valve is energized and in the second solenoid valve position, the oil pump outlet is connected to the steering gear oil inlet, and when the steering gear is adjusted to the point where the steering gear oil inlet is connected to the steering gear L oil supply port, the first oil cylinder large chamber is supplied with oil;

[0018] When the solenoid valve is energized and is in the second solenoid valve position, the oil pump outlet is connected to the steering gear oil inlet, and when the steering gear is adjusted to the steering gear oil inlet being connected to the steering gear R oil supply port, the second oil cylinder large chamber obtains oil.

[0019] Furthermore, it also includes a first valve core group, when the solenoid valve is in the second solenoid valve position, the oil pump outlet is connected to the solenoid valve, and after the hydraulic oil pumped by the oil pump outlet flows through the solenoid valve, the first valve core group is controlled to switch direction;

[0020] When the first valve core group is switched, the steering gear is adjusted to the point where the steering gear oil inlet is connected to the steering gear L oil supply port, and the first oil cylinder large chamber obtains oil;

[0021] When the first valve core group is switched, the steering gear is adjusted to the point where the steering gear oil inlet is connected to the steering gear R oil supply port, and the second oil cylinder large chamber obtains oil.

[0022] Further, the first valve core group includes a first valve core and a second valve core;

[0023] The first valve core and the second valve core are both arranged on the pipeline between the steering gear and the first oil cylinder and the second oil cylinder;

[0024] When the first valve core and the second valve core are switched, the steering gear oil inlet is connected with the steering gear L oil supply port, and the hydraulic oil flows into the first oil cylinder large chamber through the steering gear L oil supply port;

[0025] When the first valve core and the second valve core are switched, the steering gear oil inlet is connected with the steering gear L oil supply port, and the hydraulic oil flows into the second oil cylinder large chamber through the steering gear R oil supply port.

[0026] Furthermore, it also includes a pressure reducing valve, which is arranged between the solenoid valve and the oil pump outlet, so that when the solenoid valve is in the second solenoid valve position, the hydraulic oil pumped by the oil pump outlet flows into the solenoid valve after being decelerated by the pressure reducing valve, and the hydraulic oil flows through the solenoid valve and then flows into the first valve core group, so that the first valve core group is reversed.

[0027] Furthermore, the steering gear is also provided with a pressure feedback oil port, the oil pump is a variable pump, the variable pump has an external control port, the pressure feedback oil port is connected to the external control port, so that the variable pump can adjust the output power based on the information of the pressure feedback oil port.

[0028] Further, the first oil cylinder large chamber, the first oil cylinder small chamber, the second oil cylinder large chamber and the second oil cylinder small chamber are all provided with oil replenishment pipelines connected to the oil tank, and the pipelines of the first oil cylinder large chamber, the first oil cylinder small chamber, the second oil cylinder large chamber and the second oil cylinder small chamber respectively connected to the oil tank are provided with one-way valves for supplying hydraulic oil from the oil tank to the first oil cylinder large chamber, the first oil cylinder small chamber, the second oil cylinder large chamber and the second oil cylinder small chamber respectively, so as to replenish oil to the first oil cylinder large chamber, the first oil cylinder small chamber, the second oil cylinder large chamber and the second oil cylinder small chamber.

[0029] A steering method, using the above steering system, when the steering gear is turned to steer, the hydraulic oil enters the first oil cylinder small chamber and the second oil cylinder large chamber, or the first oil cylinder large chamber and the second oil cylinder small chamber through the flow amplification valve, so as to realize the rapid steering of the loader;

[0030] When the solenoid valve is turned on and the steering gear is rotated, the hydraulic oil bypasses the flow amplification valve and directly enters the first oil cylinder large chamber or the second oil cylinder large chamber to achieve slow steering of the loader.

[0031] In summary, the dual-speed steering system and steering method provided by the present invention have the following technical effects:

[0032] 1. By controlling the switch of the solenoid valve, the direction of the hydraulic oil pumped by the oil pump is adjusted. When the solenoid valve is in the closed state, that is, the solenoid valve is in the first solenoid valve position, the hydraulic oil pumped by the oil pump is adjusted through the steering gear to adjust the position of the reversing valve accordingly, so that the hydraulic oil pump, the reversing valve, the first oil cylinder and the second oil cylinder are connected, that is, the hydraulic oil flows into the small cavity of the first oil cylinder and the large cavity of the second oil cylinder respectively after the flow is amplified by the reversing valve in the flow amplification valve, or the large cavity of the first oil cylinder and the small cavity of the second oil cylinder, that is, oil is supplied to the first oil cylinder and the second oil cylinder at the same time to achieve fast steering. When the solenoid valve is in the open state, that is, the solenoid valve is in the second solenoid valve position, the hydraulic oil pumped by the oil pump will flow directly into the large cavity of the first oil cylinder or the large cavity of the second oil cylinder through the steering gear, that is, the hydraulic oil will bypass the flow amplification valve, and the adjustment of the solenoid valve realizes the oil supply of a single oil cylinder (the large cavity of the first oil cylinder or the large cavity of the second oil cylinder), thereby realizing slow steering;

[0033] 2. The hydraulic oil used to drive the reversing valve to change direction is provided with an oil branch. After the reversing valve completes the reversing, the hydraulic oil also participates in the oil supply to the first cylinder small chamber and the second cylinder large chamber, or the first cylinder large chamber and the second cylinder small chamber. That is, the flow in the steering gear will also enter the first cylinder small chamber and the second cylinder large chamber, or the first cylinder large chamber and the second cylinder small chamber, so as to make full use of energy consumption and improve the economy of the steering system.

[0034] 3. The switching between fast steering and slow steering can be flexibly adjusted according to the needs of the driver. During high-demand steering (such as steering during high-speed driving), the system provides a higher hydraulic oil flow rate to improve the steering response speed; while during low-speed operations (such as parking or fine steering), the system reduces the oil flow rate to provide a smoother and more controllable steering force, increasing the stability, safety and economy of the operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a schematic diagram of the solenoid valve of the present invention in a closed state;

[0036] Figure 2 For the present invention Figure 1 A magnified view of the left part;

[0037] Figure 3 It is a schematic diagram of the solenoid valve of the present invention in an open state;

[0038] Figure 4 For the present invention Figure 2 A magnified view of the left part;

[0039] Figure 5 This is a schematic diagram of a fourth valve core of the present invention.

[0040] Among them, the meanings of the accompanying drawings are as follows: 1. Oil tank; 2. Oil pump; 21. Oil pump oil inlet; 22. Oil pump oil outlet; 3. Solenoid valve; 4. Steering gear; 41. Steering gear oil inlet; 42. Steering gear oil return port; 43. Steering gear L oil supply port; 44. Steering gear R oil supply port; 45. Pressure feedback oil port; 5. First oil cylinder; 51. First oil cylinder large cavity; 52. First oil cylinder small cavity; 6. Second oil cylinder; 61. Second oil cylinder large cavity; 62. Second oil cylinder small cavity; 7. Flow amplification valve; 71. Reversing valve; 72. First flow amplification oil outlet; 73. Second flow amplification oil outlet; 81. First valve core; 82. Second valve core; 9. Pressure reducing valve; 10. Check valve. DETAILED DESCRIPTION

[0041] For better understanding and implementation, the technical solutions in the embodiments of the present invention will be clearly and completely described and discussed below in conjunction with the accompanying drawings of the present invention. Obviously, what is described here is only a part of the examples of the present invention, not all the examples. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0042] In order to facilitate the understanding of the embodiments of the present invention, the following will be further explained by taking specific embodiments as examples in conjunction with the drawings, and each embodiment does not constitute a limitation on the embodiments of the present invention.

[0043] In the description of the present invention, it should be noted that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the present invention.

[0044] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0045] See also Figure 1-Figure 5The present invention discloses a dual-speed steering system, including an oil tank 1, an oil pump 2, a solenoid valve 3, a steering gear 4, a first oil cylinder 5, a second oil cylinder 6 and a flow amplification valve 7. The oil pump 2 has an oil pump oil inlet 21 and an oil pump oil outlet 22, and the oil pump oil inlet 21 is connected to the oil tank 1. The solenoid valve 3 has a first solenoid valve position and a second solenoid valve position. The steering gear 4 has a steering gear oil inlet 41, a steering gear oil return port 42, a steering gear L oil supply port 43 and a steering gear R oil supply port 44, and the steering gear oil return port 42 is connected to the oil tank 1. The first oil cylinder 5 has a first oil cylinder large cavity 51 and a first oil cylinder small cavity 52. ​​The second oil cylinder 6 has a second oil cylinder large cavity 61 and a second oil cylinder small cavity 62.

[0046] The flow amplifying valve 7 has a reversing valve 71, a first flow amplifying oil outlet 72 and a second flow amplifying oil outlet 73. The reversing valve 71 has a first reversing valve position, a second reversing valve position and a third reversing valve position. The oil pump outlet 22 is connected to the reversing valve 71. The oil circuit from the oil supply port 44 of the steering gear R to the reversing valve 71 is provided with two interfaces, one of which is used to connect the reversing valve 71 so that the reversing valve 71 is switched to the first reversing valve position, and the other interface is connected to the middle part of the reversing valve 71 so that when the reversing valve 71 is switched to the first reversing valve position, the hydraulic oil of the interface flows through the reversing valve 71 and enters the first oil cylinder large chamber 51 and the second oil cylinder large chamber 52. The oil circuit from the oil cylinder small chamber 62 and the oil supply port 43 of the steering gear L to the reversing valve 71 is provided with two interfaces, one of which is used to connect the reversing valve 71 so as to switch the reversing valve 71 to the third reversing valve position, and the other interface is connected to the middle part of the reversing valve 71, so that when the reversing valve 71 is switched to the third reversing valve position, the hydraulic oil of the interface flows through the reversing valve 71 and enters the first oil cylinder small chamber 52 and the second oil cylinder large chamber 61. The second reversing valve position of the reversing valve 71 is the valve position when the reversing valve 71 is not subjected to the reversing power. When the reversing valve 71 is in the second reversing valve position, the reversing valve 71 cuts off the oil pump outlet 22 from flowing through the reversing valve 71.

[0047] When the solenoid valve 3 is in the first solenoid valve position, the oil pump outlet 22 is connected to the steering gear oil inlet 41, and when the steering gear 4 is adjusted to the steering gear oil inlet 41 being connected to the steering gear R oil supply port 44, the hydraulic oil pumped by the oil pump outlet 22 flows into the steering gear R oil supply port 44 and enters one side of the reversing valve 71, switching the reversing valve 71 to the first reversing valve position. When the reversing valve 71 is in the first reversing valve position, the reversing valve 71 converts the hydraulic oil supplied by the oil pump outlet 22 and the hydraulic oil used for the reversing oil circuit of the reversing valve 71 to the first flow amplification oil outlet 72, and transmits them to the first oil cylinder large chamber 51 and the second oil cylinder small chamber 62;

[0048] When the solenoid valve 3 is in the first solenoid valve position, the oil pump outlet 22 is connected to the steering gear oil inlet 41, and when the steering gear 4 is adjusted to the steering gear oil inlet 41 being connected to the steering gear L oil supply port 43, the hydraulic oil pumped by the oil pump outlet 22 flows into the other side of the reversing valve 71 through the steering gear L oil supply port 43, and switches the reversing valve 71 to the third reversing valve position. When the reversing valve 71 is in the third reversing valve position, the reversing valve 71 converts the hydraulic oil supplied by the oil pump outlet 22 and the hydraulic oil used for the reversing oil circuit of the reversing valve 71 to the second flow amplification oil outlet 73, and transmits them to the first oil cylinder small chamber 52 and the second oil cylinder large chamber 61;

[0049] When the solenoid valve 3 is energized and in the second solenoid valve position, the oil pump outlet 22 is connected to the steering gear oil inlet 41, and when the steering gear 4 is adjusted to the steering gear oil inlet 41 being connected to the steering gear L oil supply port 43, the first oil cylinder large chamber 51 is supplied with oil;

[0050] When the solenoid valve 3 is energized and in the second solenoid valve position, the oil pump outlet 22 is connected to the steering gear oil inlet 41, and when the steering gear 4 is adjusted to the steering gear oil inlet 41 being connected to the steering gear R oil supply port 44, the second oil cylinder large chamber 61 obtains oil.

[0051] Specifically, the oil pump 2 has an oil pump inlet 21 and an oil pump outlet 22, and the oil pump inlet 21 is connected to the oil tank 1. The solenoid valve 3 has a first solenoid valve position and a second solenoid valve position. The specific valve position adjustment of the solenoid valve 3 can be set according to actual conditions. In this embodiment, the first solenoid valve 3 is the normal position of the solenoid valve 3. When the solenoid valve 3 is energized, the solenoid valve 3 will switch to the second solenoid valve position. The steering gear 4 has a steering gear oil inlet 41, a steering gear oil return port 42, a steering gear L oil supply port 43 and a steering gear R oil supply port 44. The steering gear oil inlet 41 is an interface for supplying oil to the steering gear 4. The steering gear oil return port 42 is connected to the oil tank 1 for returning oil. The steering gear L oil supply port 43 is an interface that the steering gear 4 oil supply port can be connected to when the steering gear 4 turns left. The steering gear R oil supply port 44 is an interface that the steering gear 4 oil supply port can be connected to when the steering gear 4 turns right. The first oil cylinder 5 has a first oil cylinder large chamber 51 and a first oil cylinder small chamber 52, and the second oil cylinder 6 has a second oil cylinder large chamber 61 and a second oil cylinder small chamber 62, wherein the large chamber (the first oil cylinder large chamber 51 and the second oil cylinder large chamber 61) is a thrust chamber, and when the hydraulic oil enters the large chamber, it can generate a large thrust. This allows the oil cylinder to overcome external loads, push the piston rod outward, and perform actions that require great force, such as steering operations of a vehicle. The small chamber (the first oil cylinder small chamber 52 and the second oil cylinder small chamber 62) is a return chamber, and when the hydraulic oil enters the small chamber, it can push the piston rod to provide a return force, that is, help the piston rod return to its initial position. This helps to control the retraction speed of the piston rod. The flow amplifying valve 7 has a reversing valve 71, a first flow amplifying oil outlet 72 and a second flow amplifying oil outlet 73. The reversing valve 71 has a first reversing valve position, a second reversing valve position and a third reversing valve position. When the reversing valve 71 is in the first reversing valve position, the reversing valve 71 converts the hydraulic oil supplied from the oil pump outlet 22 to the first flow amplifying oil outlet 72; when the reversing valve 71 is in the second reversing valve position, the reversing valve 71 cuts off the oil pump outlet 22 from flowing through the reversing valve 71; when the reversing valve 71 is in the third reversing valve position, the reversing valve 71 converts the hydraulic oil supplied from the oil pump outlet 22 to the second flow amplifying oil outlet 73. The oil circuit from the oil supply port 44 of the steering gear R to the reversing valve 71 is provided with two interfaces, one of which is used to connect the reversing valve 71 for switching the reversing valve 71 to the first reversing valve position, and the other interface is connected to the middle of the reversing valve 71, so that when the reversing valve 71 is switched to the first reversing valve position, the hydraulic oil of the interface flows through the reversing valve 71 and enters the first cylinder small chamber 51 and the second cylinder large chamber 62. The oil circuit from the oil supply port 43 of the steering gear L to the reversing valve 71 is provided with two interfaces, one of which is used to connect the reversing valve 71 for switching the reversing valve 71 to the third reversing valve position, and the other interface is connected to the middle of the reversing valve 71, so that when the reversing valve 71 is switched to the third reversing valve position, the hydraulic oil of the interface flows through the reversing valve 71 and enters the first cylinder small chamber 52 and the second cylinder large chamber 61.

[0052] It should be noted that the connection method between the above components is not limited here, and it can be connected through pipelines or pipeline switching through sliding valves, which is not limited here.

[0053] In some embodiments, the steering system further includes a first valve core 81 group, when the solenoid valve 3 is in the second solenoid valve position, the oil pump outlet 22 is connected to the solenoid valve 3, and the hydraulic oil pumped by the oil pump outlet 22 flows through the solenoid valve 3, and controls the first valve core 81 group to switch direction;

[0054] When the first valve core 81 is reversed, the steering gear 4 is adjusted to the point where the steering gear oil inlet 41 is connected to the steering gear L oil supply port 43, and the first oil cylinder large chamber 51 is supplied with oil;

[0055] When the first valve core 81 is reversed, the steering gear 4 is adjusted to the point where the steering gear oil inlet 41 is connected to the steering gear R oil supply port 44 , and the second oil cylinder large chamber 61 obtains oil.

[0056] Specifically, the switching of the first valve core 81 group is used to adjust whether the hydraulic oil bypasses the flow amplification valve 7, thereby simplifying the setting of the oil circuit and no longer requiring more interfaces and more connections to realize the connection between the various components of the above structure.

[0057] In some embodiments, the first valve core 81 group includes a first valve core 81 and a second valve core 82;

[0058] The first valve core 81 and the second valve core 82 are both arranged on the pipeline between the steering gear 4 and the first oil cylinder 5 and the second oil cylinder 6;

[0059] When the first valve core 81 and the second valve core 82 are switched, the steering gear oil inlet 41 is connected with the steering gear L oil supply port 43, and the hydraulic oil flows into the first oil cylinder large chamber 51 through the steering gear L oil supply port 43;

[0060] When the first valve core 81 and the second valve core 82 are switched, the steering gear oil inlet 41 is connected to the steering gear L oil supply port 43 , and the hydraulic oil flows into the second oil cylinder large chamber 61 through the steering gear R oil supply port 44 .

[0061] Specifically, the first valve core 81 and the second valve core 82 are located on the pipeline between the steering gear 4 and the first oil cylinder 5 and the second oil cylinder 6, and are used to directly control the oil to enter the specific chambers of the first oil cylinder 5 and the second oil cylinder 6. When the first valve core 81 and the second valve core 82 are in the non-switching state, the hydraulic oil flowing out through the oil supply port 43 of the steering gear L will be affected by the first valve core 81 and flow to the other side of the reversing valve 71, that is, flow to the direction of driving the reversing valve 71 to switch to the third reversing valve position, so as to drive the reversing valve 71 to switch, and the second valve core 82 guides the hydraulic oil flowing through the reversing valve 71 to be diverted to the small chamber 52 of the first oil cylinder and the large chamber 61 of the second oil cylinder. Correspondingly, when the first valve core 81 and the second valve core 82 are in the non-switching state, the hydraulic oil flowing out through the oil supply port 44 of the steering gear R will be affected by the first valve core 81 and flow to one side of the reversing valve 71, that is, flow to the direction of driving the reversing valve 71 to switch to the first reversing valve position, so as to drive the reversing valve 71 to switch, and the second valve core 82 guides the hydraulic oil flowing through the reversing valve 71 to be diverted to the first oil cylinder large chamber 51 and the second oil cylinder small chamber 62. After the first valve core 81 and the second valve core 82 are switched, the hydraulic oil can bypass the flow amplification valve 7 and directly flow into the first oil cylinder large chamber 51 or the second oil cylinder large chamber 61.

[0062] In some embodiments, the steering system also includes a pressure reducing valve 9, which is arranged between the solenoid valve 3 and the oil pump outlet 22, so that when the solenoid valve 3 is in the second solenoid valve position, the hydraulic oil pumped by the oil pump outlet 22 flows into the solenoid valve 3 after being decelerated by the pressure reducing valve 9, and the hydraulic oil flows through the solenoid valve 3 and then flows into the first valve core 81 group, so that the first valve core 81 group is reversed.

[0063] Specifically, the pressure reducing valve 9 is located between the oil pump outlet 22 and the solenoid valve 3, and is used to adjust the pressure of the high-pressure hydraulic oil provided by the oil pump 2, so as to achieve the effect of reducing and stabilizing the pressure. The hydraulic oil after the pressure reduction flows through the solenoid valve 3 and flows into the first valve core 81 group, which is used for the switching of the first valve core 81 group. Therefore, the pressure reducing valve 9 is used to adjust the pressure of the hydraulic oil. After passing through the solenoid valve 3, the hydraulic oil directly acts on the first valve core 81 group, causing it to switch direction. The first valve core 81 group determines the final oil flow direction according to the position of the steering gear 4 to achieve the required steering operation. Since the oil pressure has been properly adjusted, the first valve core 81 group can complete the switching under safe and stable conditions.

[0064] In some embodiments, the steering gear 4 is also provided with a pressure feedback oil port 45, the oil pump 2 is a variable pump, the variable pump has an external control port, and the pressure feedback oil port 45 is connected to the external control port so that the variable pump can adjust the output power based on the information of the pressure feedback oil port 45.

[0065] Specifically, the steering gear 4 is responsible for distributing hydraulic oil according to the driver's operation, and is provided with a pressure feedback oil port 45 for feeding back pressure information during the steering process to the variable pump. The variable pump has an external control port, which can receive signals from the pressure feedback oil port 45 and adjust its displacement according to these signals, thereby changing the output power.

[0066] Specifically, when the driver operates the steering wheel to make the steering gear 4 work, the steering gear 4 will obtain hydraulic oil from the oil pump 2 according to the steering demand. At the same time, the high-pressure oil inside the steering gear 4 will be fed back to the load-sensitive port, which is connected to the pressure feedback oil port 45. The pressure feedback oil port 45 transmits the pressure information inside the steering gear 4 to the external control port of the variable pump. After the variable pump receives the signal from the pressure feedback oil port 45, it will adjust its displacement according to these signals. If the steering demand increases, the pressure inside the steering gear 4 will rise, and the variable pump will increase the displacement after receiving this signal, thereby increasing the output power to meet the steering demand. Conversely, if the steering demand decreases, the variable pump will reduce the displacement and reduce the output power.

[0067] In some embodiments, the first cylinder large chamber 51, the first cylinder small chamber 52, the second cylinder large chamber 61 and the second cylinder small chamber 62 are all provided with oil replenishment pipelines connected to the oil tank 1, and the pipelines of the first cylinder large chamber 51, the first cylinder small chamber 52, the second cylinder large chamber 61 and the second cylinder small chamber 62 respectively connected to the oil tank 1 are provided with one-way valves 10 for supplying hydraulic oil from the oil tank 1 to the first cylinder large chamber 51, the first cylinder small chamber 52, the second cylinder large chamber 61 and the second cylinder small chamber 62 respectively, so as to replenish the first cylinder large chamber 51, the first cylinder small chamber 52, the second cylinder large chamber 61 and the second cylinder small chamber 62.

[0068] Specifically, independent oil replenishment pipes connected to the oil tank 1 are provided between the first oil cylinder large chamber 51 and the oil tank 1, between the first oil cylinder small chamber 52 and the oil tank 1, between the second oil cylinder large chamber 61 and the oil tank 1, and between the second oil cylinder small chamber 62 and the oil tank 1. Correspondingly, in order not to affect the oiling of the first oil cylinder large chamber 51, the first oil cylinder small chamber 52, the second oil cylinder large chamber 61 and the second oil cylinder small chamber 62, a one-way valve 10 is provided on the pipelines between the first oil cylinder large chamber 51 and the oil tank 1, between the first oil cylinder small chamber 52 and the oil tank 1, between the second oil cylinder large chamber 61 and the oil tank 1, and between the second oil cylinder small chamber 62 and the oil tank 1, so that each oil replenishment pipe can only replenish oil and will not affect the oiling.

[0069] A steering method, using the above steering system, when the steering gear 4 is turned to steer, the hydraulic oil enters the first oil cylinder small chamber 52 and the second oil cylinder large chamber 61, or the first oil cylinder large chamber 51 and the second oil cylinder small chamber 62 through the flow amplification valve 7, so as to realize the rapid steering of the loader;

[0070] When the solenoid valve 3 is opened and the steering gear 4 is rotated, the hydraulic oil bypasses the flow amplification valve 7 and directly enters the first cylinder large chamber 51 or the second cylinder large chamber 61 to achieve slow steering of the loader.

[0071] Working principle:

[0072] When quick turns are required, refer to Figure 1 and Figure 2 As shown, the solenoid valve 3 is in a closed state, that is, the solenoid valve 3 is in the first solenoid valve position, and the hydraulic oil pumped by the oil pump outlet 22 is directly pumped to the steering gear oil inlet 41, and then the steering gear oil inlet 41 is connected to the steering gear L oil supply port 43 or the steering gear R oil supply port 44, which is divided into two situations:

[0073] a. When the steering gear oil inlet 41 is connected to the steering gear L oil supply port 43, the hydraulic oil passes through the first valve core 81 in the non-switching state and enters the pipeline between the first valve core 81 and the reversing valve 71. The pipeline between the first valve core 81 and the reversing valve 71 has two interfaces, one of which is connected to one side of the reversing valve 71, thereby pushing the reversing valve 71 to switch to the third reversing valve position, and the other interface is when the reversing valve 71 switches to the third reversing valve position, and the hydraulic oil inside can pass through the reversing valve 71 to flow to the second valve core 82. At the same time, the hydraulic oil pumped by the oil pump outlet 22 passes through the reversing valve 71, and together with the above-mentioned hydraulic oil, flows into the second valve core 82 through the second flow amplification oil outlet 73. The second valve core 82 diverts the hydraulic oil and flows to the first oil cylinder small chamber 52 and the second oil cylinder large chamber 61 respectively, thereby performing rapid steering;

[0074] b. When the steering gear oil inlet 41 is connected to the steering gear R oil supply port 44, the hydraulic oil passes through the first valve core 81 in the non-switching state and enters the pipeline between the first valve core 81 and the reversing valve 71. The pipeline between the first valve core 81 and the reversing valve 71 has two interfaces, one of which is connected to one side of the reversing valve 71, thereby pushing the reversing valve 71 to switch to the first reversing valve position, and the other interface is when the reversing valve 71 switches to the first reversing valve position, and the hydraulic oil inside can pass through the reversing valve 71 to flow to the second valve core 82. At the same time, the hydraulic oil pumped by the oil pump outlet 22 passes through the reversing valve 71, and together with the above-mentioned hydraulic oil, flows into the second valve core 82 through the second flow amplification oil outlet 73. The second valve core 82 diverts the hydraulic oil and flows to the first oil cylinder large chamber 51 and the second oil cylinder small chamber 62 respectively, thereby performing rapid steering;

[0075] When slow steering is required, refer to Figure 3 and Figure 4As shown, the solenoid valve 3 is in the open state, that is, the solenoid valve 3 is in the second solenoid valve position, and the hydraulic oil pumped by the oil pump outlet 22 is divided into two paths, one of which enters the pressure reducing valve 9 and then enters the solenoid valve 3 in the second solenoid valve position, and then the hydraulic oil after passing through the solenoid valve 3 acts on the first valve core 81 and the second valve core 82 through the pipeline diversion, thereby causing the first valve core 81 and the second valve core 82 to switch. The other path directly enters the reversing oil inlet, and the hydraulic oil entering the reversing oil inlet is divided into two situations according to whether the steering gear oil inlet 41 is connected to the steering gear L oil supply port 43 or the steering gear R oil supply port 44:

[0076] a. When the steering gear oil inlet 41 is connected to the steering gear L oil supply port 43, the hydraulic oil passes through the first valve core 81 and the second valve core 82 in sequence, and directly enters the first oil cylinder large chamber 51, thereby performing slow steering. Correspondingly, the first oil cylinder small chamber 52, the second oil cylinder large chamber 61 and the second oil cylinder small chamber 62 are all in a floating state, and the pipelines between the first oil cylinder small chamber 52, the second oil cylinder large chamber 61 and the second oil cylinder small chamber 62 and the oil tank 1 replenish the three with oil;

[0077] b. When the steering gear oil inlet 41 is connected to the steering gear R oil supply port 44, the hydraulic oil passes through the first valve core 81 and the second valve core 82 in sequence, and directly enters the second cylinder large chamber 61, thereby performing slow steering. Correspondingly, the first cylinder large chamber 51, the first cylinder small chamber 52 and the second cylinder small chamber 62 are all in a floating state, and the pipeline between the first cylinder large chamber 51, the first cylinder small chamber 52 and the second cylinder small chamber 62 and the oil tank 1 replenishes oil to the three.

[0078] The technical means disclosed in the scheme of the present invention are not limited to the technical means disclosed in the above-mentioned implementation mode, but also include technical schemes composed of any combination of the above-mentioned technical features. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications are also regarded as the protection scope of the present invention.

Claims

1. A dual-speed steering system, characterized in that: include: Fuel tank (1); An oil pump (2), the oil pump (2) having an oil pump inlet (21) and an oil pump outlet (22), the oil pump inlet (21) being in communication with the oil tank (1); A solenoid valve (3), wherein the solenoid valve (3) has a first solenoid valve position and a second solenoid valve position; A steering gear (4), the steering gear (4) comprising a steering gear oil inlet (41), a steering gear oil return port (42), a steering gear L oil supply port (43) and a steering gear R oil supply port (44), the steering gear oil return port (42) being in communication with the oil tank (1); A first oil cylinder (5), the first oil cylinder (5) comprising a first oil cylinder large chamber (51) and a first oil cylinder small chamber (52); A second oil cylinder (6), the second oil cylinder (6) having a second oil cylinder large chamber (61) and a second oil cylinder small chamber (62); A flow amplifying valve (7), the flow amplifying valve (7) having a reversing valve (71), a first flow amplifying oil outlet (72) and a second flow amplifying oil outlet (73), the reversing valve (71) having a first reversing valve position, a second reversing valve position and a third reversing valve position, the oil pump oil outlet (22) being in communication with the reversing valve (71), the oil circuit from the steering gear R oil supply port (44) to the reversing valve (71) being provided with two interfaces, one of which is used to connect the reversing valve (71) so as to switch the reversing valve (71) to the first reversing valve position, and the other interface being connected to the middle of the reversing valve (71) so that when the reversing valve (71) is switched to the first reversing valve position, the hydraulic oil of the interface flows through the reversing valve (71) and enters the first oil cylinder large chamber (51) and the first oil cylinder large chamber (52). The second oil cylinder small chamber (62), the oil circuit from the steering gear L oil supply port (43) to the reversing valve (71) is provided with two interfaces, one of which is used to connect the reversing valve (71) so as to switch the reversing valve (71) to the third reversing valve position, and the other interface is connected to the middle of the reversing valve (71), so that when the reversing valve (71) is switched to the third reversing valve position, the hydraulic oil of the interface flows through the reversing valve (71) and enters the first oil cylinder small chamber (52) and the second oil cylinder large chamber (61). The second reversing valve position of the reversing valve (71) is the valve position when the reversing valve (71) is not subjected to the reversing power. When the reversing valve (71) is in the second reversing valve position, the reversing valve (71) cuts off the oil pump outlet (22) from flowing through the reversing valve (71); When the solenoid valve (3) is in the first solenoid valve position, the oil pump outlet (22) is connected to the steering gear oil inlet (41). When the steering gear (4) is adjusted to the point where the steering gear oil inlet (41) is connected to the steering gear R oil supply port (44), the hydraulic oil pumped by the oil pump outlet (22) flows into the steering gear R oil supply port (44) and enters one side of the reversing valve (71), switching the reversing valve (71) to the first reversing valve position. When the reversing valve (71) is in the first reversing valve position, the reversing valve (71) converts the hydraulic oil supplied by the oil pump outlet (22) and the hydraulic oil used for the reversing oil circuit of the reversing valve (71) to the first flow amplification oil outlet (72) and transmits them to the first oil cylinder large chamber (51) and the second oil cylinder small chamber (62). When the solenoid valve (3) is in the first solenoid valve position, the oil pump outlet (22) is connected to the steering gear oil inlet (41). When the steering gear (4) is adjusted to the point where the steering gear oil inlet (41) is connected to the steering gear L oil supply port (43), the hydraulic oil pumped by the oil pump outlet (22) flows in through the steering gear L oil supply port (43) and enters the other side of the reversing valve (71), switching the reversing valve (71) to the third reversing valve position. When the reversing valve (71) is in the third reversing valve position, the reversing valve (71) converts the hydraulic oil supplied by the oil pump outlet (22) and the hydraulic oil used for the reversing oil circuit of the reversing valve (71) to the second flow amplification oil outlet (73) and transmits them to the first oil cylinder small chamber (52) and the second oil cylinder large chamber (61); When the solenoid valve (3) is energized and in the second solenoid valve position, the oil pump outlet (22) is connected to the steering gear oil inlet (41), and when the steering gear (4) is adjusted to the point where the steering gear oil inlet (41) is connected to the steering gear L oil supply port (43), the first oil cylinder large chamber (51) is supplied with oil; When the solenoid valve (3) is energized and in the second solenoid valve position, the oil pump outlet (22) is connected to the steering gear oil inlet (41), and when the steering gear (4) is adjusted so that the steering gear oil inlet (41) is connected to the steering gear R oil supply port (44), the second oil cylinder large chamber (61) receives oil.

2. A dual-speed steering system according to claim 1, characterized in that: It also includes a first valve core (81) group. When the solenoid valve (3) is in the second solenoid valve position, the oil pump outlet (22) is connected to the solenoid valve (3), and after the hydraulic oil pumped by the oil pump outlet (22) flows through the solenoid valve (3), the first valve core (81) group is controlled to switch direction. When the first valve core (81) group is switched, the steering gear (4) is adjusted to the point where the steering gear oil inlet (41) is connected to the steering gear L oil supply port (43), and the first oil cylinder large chamber (51) is supplied with oil; When the first valve core (81) group is switched, the steering gear (4) is adjusted to the point where the steering gear oil inlet (41) is connected to the steering gear R oil supply port (44), and the second oil cylinder large chamber (61) receives oil.

3. A dual-speed steering system according to claim 2, characterized in that: The first valve core (81) group includes a first valve core (81) and a second valve core (82); The first valve core (81) and the second valve core (82) are both arranged on a pipeline between the steering gear (4) and the first oil cylinder (5) and the second oil cylinder (6); When the first valve core (81) and the second valve core (82) are switched, the steering gear oil inlet (41) is connected to the steering gear L oil supply port (43), and the hydraulic oil flows into the first oil cylinder large chamber (51) through the steering gear L oil supply port (43); When the first valve core (81) and the second valve core (82) are switched, the steering gear oil inlet (41) is connected to the steering gear L oil supply port (43), and the hydraulic oil flows into the second oil cylinder large chamber (61) through the steering gear R oil supply port (44).

4. A dual-speed steering system according to claim 3, characterized in that: The invention also comprises a pressure reducing valve (9), which is arranged between the solenoid valve (3) and the oil pump outlet (22), so that when the solenoid valve (3) is in the second solenoid valve position, the hydraulic oil pumped by the oil pump outlet (22) flows into the solenoid valve (3) after being decelerated by the pressure reducing valve (9), and the hydraulic oil flows into the first valve core (81) group after flowing through the solenoid valve (3), so that the first valve core (81) group is reversed.

5. A dual-speed steering system according to any one of claims 1 to 4, characterized in that: The steering gear (4) is also provided with a pressure feedback oil port (45); the oil pump (2) is a variable displacement pump having an external control port; the pressure feedback oil port (45) is connected to the external control port so that the variable displacement pump can adjust output power based on information from the pressure feedback oil port (45).

6. A dual-speed steering system according to any one of claims 1 to 4, characterized in that: The first large oil cylinder chamber (51), the first small oil cylinder chamber (52), the second large oil cylinder chamber (61) and the second small oil cylinder chamber (62) are all provided with oil replenishment pipelines connected to the oil tank (1), and the pipelines connecting the first large oil cylinder chamber (51), the first small oil cylinder chamber (52), the second large oil cylinder chamber (61) and the second small oil cylinder chamber (62) with the oil tank (1) are provided with one-way valves (10) for supplying hydraulic oil from the oil tank (1) to the first large oil cylinder chamber (51), the first small oil cylinder chamber (52), the second large oil cylinder chamber (61) and the second small oil cylinder chamber (62) respectively, so as to replenish the first large oil cylinder chamber (51), the first small oil cylinder chamber (52), the second large oil cylinder chamber (61) and the second small oil cylinder chamber (62).

7. A steering method, using the steering system according to any one of claims 1 to 6, characterized in that: When the steering gear (4) is turned to perform steering, the hydraulic oil enters the first oil cylinder small chamber (52) and the second oil cylinder large chamber (61), or the first oil cylinder large chamber (51) and the second oil cylinder small chamber (62) through the flow amplification valve (7), so as to realize rapid steering of the loader; When the solenoid valve (3) is opened and the steering gear (4) is rotated, the hydraulic oil bypasses the flow amplification valve (7) and directly enters the first oil cylinder large chamber (51) or the second oil cylinder large chamber (61), thereby realizing slow steering of the loader.

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