Full-hydraulic load-sensitive steering system and coal car

Abstract

The invention relates to the technical field of steering systems, in particular to a full-hydraulic load-sensitive steering system and a coal conveyor, and the full-hydraulic load-sensitive steering system comprises a hydraulic steering gear connected with a steering wheel; the hydraulic steering gear is connected with the flow amplifier through a pipeline; an oil port S of the plunger pump is connected with the hydraulic oil tank through a pipeline; an oil port B of the plunger pump is connected with an oil port HP of the flow amplifier through a pipeline; an X oil port of the plunger pump is connected with a second LS oil port of the flow amplifier through a pipeline; an HT oil port of the flow amplifier is connected with the hydraulic oil tank through a pipeline; the steering oil cylinder is connected with a CL oil port and a CR oil port of the flow amplifier through pipelines. A load sensitive mode is adopted for control, a hydraulic steering gear is combined with a flow amplifier, and low-pressure small-flow control over high-pressure large-flow is achieved. The hydraulic steering gear is controlled by the steering wheel to achieve left turning and right turning of the underground coal conveyor, operation is stable, and the steering wheel is light, efficient and energy-saving.

Description

Technical Field

[0001] The present application relates to the technical field of steering systems, and in particular to a full hydraulic load-sensitive steering system and a coal truck. Background Art

[0002] Underground coal trucks are mainly used for coal transportation in coal mines. They can efficiently transport coal from underground to the surface to ensure the normal production and operation of the mine. The steering system of traditional underground coal trucks uses a plunger pump as a power element, and controls the steering cylinder to turn left and right through a handle-type manual reversing valve.

[0003] However, the traditional steering system uses a manual reversing valve to control the steering cylinder for left and right steering. The driver manually controls the reversing valve to complete the vehicle's left and right steering. The steering speed and angle of the handle are difficult to control, and the vehicle steering is unstable. Summary of the invention

[0004] The present application aims to solve at least one of the technical problems in the prior art or related art that the traditional steering system uses a manual reversing valve to control the steering cylinder for left and right steering, the driver manually controls the reversing valve to complete the left and right steering of the vehicle, the steering speed and angle of the handle operation are difficult to control, and the vehicle steering is unstable.

[0005] To this end, the present application provides a fully hydraulic load-sensitive steering system, which adopts load-sensitive control. The hydraulic steering gear is combined with a flow amplifier to achieve low-pressure and small flow to control high-pressure and large flow; the hydraulic steering gear is controlled by the steering wheel to realize left and right turns of the underground coal truck, with smooth operation, light steering wheel, and high efficiency and energy saving.

[0006] The present application also provides a coal truck including the above-mentioned full hydraulic load-sensing steering system.

[0007] A fully hydraulic load-sensitive steering system provided in accordance with an embodiment of the first aspect of the present application includes: a hydraulic steering gear connected to a steering wheel; a first P oil port of the hydraulic steering gear connected to a second P oil port of a flow amplifier through a pipeline; a first T oil port of the hydraulic steering gear connected to a second T oil port of the flow amplifier through a pipeline; a first L oil port of the hydraulic steering gear connected to a second L oil port of the flow amplifier through a pipeline; a first R oil port of the hydraulic steering gear connected to a second R oil port of the flow amplifier through a pipeline; a first LS oil port of the hydraulic steering gear connected to a second LS oil port of the flow amplifier through a pipeline; an S oil port of a plunger pump connected to a hydraulic oil tank through a pipeline; a B oil port of the plunger pump connected to an HP oil port of the flow amplifier through a pipeline; an X oil port of the plunger pump connected to a second LS oil port of the flow amplifier through a pipeline; a HT oil port of the flow amplifier connected to a hydraulic oil tank through a pipeline; and a steering cylinder connected to CL oil ports and CR oil ports of the flow amplifier through pipelines, respectively.

[0008] Optionally, the hydraulic steering gear includes: a first reversing valve, which is configured to close the first L oil port and the first R oil port when the steering wheel is in the middle position, so that the first reversing valve is in a closed state; when the steering wheel is in a left turn position, the first reversing valve is in a state where the first L oil port is connected to the first P oil port, and the first R oil port is connected to the first T oil port; when the steering wheel is in a right turn position, the first reversing valve is in a state where the first R oil port is connected to the first P oil port, and the first L oil port is connected to the first T oil port.

[0009] Optionally, the hydraulic steering gear also includes: a gerotor motor, which is configured to be in a closed state when the steering wheel is in a middle position; when the steering wheel is in a left turn position, the oil enters the gerotor motor through the first reversing valve, causing the gerotor motor to assist the steering wheel to rotate to the left; when the steering wheel is in a right turn position, the oil enters the gerotor motor through the first reversing valve, causing the gerotor motor to assist the steering wheel to rotate to the right.

[0010] Optionally, the flow amplifier includes: a second reversing valve and an amplifying valve, the second reversing valve being configured so that when oil enters the second L oil port, the second reversing valve is in a state where the CL oil port is connected to the amplifying valve, and the CR oil port is connected to the HT oil port; when oil enters the second R oil port, the second reversing valve is in a state where the CR oil port is connected to the liquid inlet of the amplifying valve, and the CL oil port is connected to the HT oil port; the amplifying valve is configured to connect to the HP oil port and play a flow amplification role.

[0011] Optionally, the amplifying valve includes: an outer valve core and an inner valve core, the inner valve core is arranged inside the outer valve core; the inner valve core and the outer valve core are connected through a pipeline; the area of ​​the outer valve core is larger than that of the inner valve core.

[0012] Optionally, the flow amplifier also includes: a priority valve, wherein the liquid inlet of the priority valve is connected to the HP oil port via a pipeline; the first output oil port of the priority valve is connected to the first P oil port via a pipeline, and the second output oil port of the priority valve is connected to the second P oil port via a pipeline; the priority valve is configured such that when the HP oil port pressure is less than a preset threshold value, the first output oil port of the priority valve is connected to the HP oil port; when the HP oil port pressure is greater than the preset threshold value, the first output oil port and the second output oil port of the priority valve are simultaneously connected to the HP oil port.

[0013] Optionally, the flow amplifier includes: a first buffer valve and a second buffer valve, the first buffer valve is arranged on the pipeline between the CL oil port and the HT oil port, and the second buffer valve is arranged on the pipeline between the CR oil port and the HT oil port.

[0014] Optionally, the plunger pump includes: a hydraulic pump and a load-sensing valve, the hydraulic pump is configured to extract oil from the hydraulic oil tank; the load-sensing valve is configured to adjust the output power of the hydraulic pump according to the oil pressure of the X oil port.

[0015] Optionally, the full hydraulic load-sensing steering system further includes: a filter, which is arranged on a connecting pipeline between the B oil port of the plunger pump and the HP oil port of the flow amplifier.

[0016] A coal truck provided in the second aspect of the present application is provided with the above-mentioned full hydraulic load-sensitive steering system. Since the full hydraulic load-sensitive steering system has the above-mentioned technical effects, the coal truck provided with the full hydraulic load-sensitive steering system should also have corresponding technical effects.

[0017] One of the above technical solutions has at least the following advantages or beneficial effects: For a full hydraulic load-sensitive steering system and a coal truck provided in an embodiment of the present application, the full hydraulic load-sensitive steering system includes: a hydraulic steering gear, connected to a steering wheel; a first P oil port of the hydraulic steering gear is connected to a second P oil port of a flow amplifier through a pipeline; a first T oil port of the hydraulic steering gear is connected to a second T oil port of the flow amplifier through a pipeline; a first L oil port of the hydraulic steering gear is connected to a second L oil port of the flow amplifier through a pipeline; a first R oil port of the hydraulic steering gear is connected to a second R oil port of the flow amplifier through a pipeline; a first LS oil port of the hydraulic steering gear is connected to a second LS oil port of the flow amplifier through a pipeline; an S oil port of a plunger pump is connected to a hydraulic oil tank through a pipeline; a B oil port of a plunger pump is connected to an HP oil port of a flow amplifier through a pipeline; an X oil port of a plunger pump is connected to a second LS oil port of a flow amplifier through a pipeline; a HT oil port of a flow amplifier is connected to a hydraulic oil tank through a pipeline; and a steering cylinder is respectively connected to a CL oil port and a CR oil port of a flow amplifier through pipelines. It adopts load-sensitive control, and the hydraulic steering gear is combined with a flow amplifier to achieve low-pressure and small flow to control high-pressure and large flow. The hydraulic steering gear is controlled by the steering wheel to realize left and right turns of the underground coal truck. The operation is smooth, the steering wheel is light, and it is highly efficient and energy-saving. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solution of the present application, the drawings required for use in the embodiments are briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0019] Figure 1 A schematic diagram of the principle of a full hydraulic load-sensing steering system provided in an embodiment of the present application is shown.

[0020] Description of reference numerals: 1. Hydraulic oil tank, 2. Plunger pump, 21. Hydraulic pump, 22. Load sensing valve, 3. Filter, 4. Hydraulic steering gear, 41. First reversing valve, 42. Cycloidal motor, 5. Flow amplifier, 51. Second reversing valve, 52. Amplifying valve, 521. External valve core, 522. Internal valve core, 53. Priority valve, 54. First buffer valve, 55. Second buffer valve, 56. Third buffer valve, 6. Steering cylinder. DETAILED DESCRIPTION

[0021] In order to better explain the present application and facilitate understanding, the present application is described in detail below through specific implementation methods in conjunction with the accompanying drawings.

[0022] As mentioned above, the traditional steering system uses a manual reversing valve to control the steering cylinder for left and right steering. The driver manually controls the reversing valve to complete the vehicle's left and right steering. The steering speed and angle of the handle are difficult to control, and the vehicle steering is unstable.

[0023] In order to solve at least one of the technical problems existing in the prior art or related art, the present application provides a full hydraulic load-sensitive steering system and a coal truck, the full hydraulic load-sensitive steering system comprising: a hydraulic steering gear connected to a steering wheel; a first P oil port of the hydraulic steering gear is connected to a second P oil port of a flow amplifier through a pipeline; a first T oil port of the hydraulic steering gear is connected to a second T oil port of the flow amplifier through a pipeline; a first L oil port of the hydraulic steering gear is connected to a second L oil port of the flow amplifier through a pipeline; a first R oil port of the hydraulic steering gear is connected to a second R oil port of the flow amplifier through a pipeline; a first LS oil port of the hydraulic steering gear is connected to a second LS oil port of the flow amplifier through a pipeline; an S oil port of a plunger pump is connected to a hydraulic oil tank through a pipeline; a B oil port of a plunger pump is connected to an HP oil port of a flow amplifier through a pipeline; an X oil port of a plunger pump is connected to a second LS oil port of a flow amplifier through a pipeline; a HT oil port of a flow amplifier is connected to a hydraulic oil tank through a pipeline; and a steering cylinder is respectively connected to a CL oil port and a CR oil port of the flow amplifier through a pipeline. It adopts load-sensitive control, and the hydraulic steering gear is combined with a flow amplifier to achieve low-pressure and small flow to control high-pressure and large flow. The hydraulic steering gear is controlled by the steering wheel to realize left and right turns of the underground coal truck. The operation is smooth, the steering wheel is light, and it is highly efficient and energy-saving.

[0024] A full hydraulic load sensing steering system according to some embodiments provided by the present application will be described below with reference to the accompanying drawings.

[0025] See also Figure 1A fully hydraulic load-sensitive steering system provided by an embodiment of the first aspect of the present application includes: a hydraulic steering gear 4, connected to a steering wheel; a first P oil port of the hydraulic steering gear 4 is connected to a second P oil port of a flow amplifier 5 through a pipeline; a first T oil port of the hydraulic steering gear 4 is connected to a second T oil port of the flow amplifier 5 through a pipeline; a first L oil port of the hydraulic steering gear 4 is connected to a second L oil port of the flow amplifier 5 through a pipeline; a first R oil port of the hydraulic steering gear 4 is connected to a second R oil port of the flow amplifier 5 through a pipeline; a first LS oil port of the hydraulic steering gear 4 is connected to a second LS oil port of the flow amplifier 5 through a pipeline; an S oil port of a plunger pump 2 is connected to a hydraulic oil tank 1 through a pipeline; a B oil port of the plunger pump 2 is connected to an HP oil port of a flow amplifier 5 through a pipeline; an X oil port of the plunger pump 2 is connected to a second LS oil port of the flow amplifier 5 through a pipeline; a HT oil port of the flow amplifier 5 is connected to a hydraulic oil tank 1 through a pipeline; and a steering cylinder 6 is respectively connected to a CL oil port and a CR oil port of the flow amplifier 5 through pipelines.

[0026] The first P oil port of the hydraulic steering gear 4 is the liquid inlet, the first T oil port is the liquid return port, the first L oil port is the left output oil port, the first R oil port is the right output oil port, and the first LS oil port is the load-sensitive control oil port. The steering wheel is used to control whether the first L oil port and the first R oil port of the hydraulic steering gear 4 output oil. The oil is extracted from the hydraulic oil tank 1 through the plunger pump 2 and enters the first P oil port, and enters the flow amplifier 5 from the first L oil port or the first R oil port according to the steering of the steering wheel. At the same time, the return liquid returns to the hydraulic oil tank 1 through the first T oil port to form a cycle. The hydraulic steering gear is controlled by the steering wheel to realize the left and right turns of the underground coal truck. The operation is smooth, the steering wheel is light, and it is highly efficient and energy-saving.

[0027] The second P oil port of the flow amplifier 5 is the liquid inlet, the second T oil port is the liquid return port, the second L oil port is the left input oil port, the second R oil port is the right input oil port, the second LS oil port is the load-sensing control oil port, the HP oil port is the large-flow liquid inlet, and the HT oil port is the large-flow liquid return port. The oil enters the flow amplifier 5 from the first L oil port or the first R oil port of the hydraulic steering gear 4. The flow amplifier 5 amplifies the flow of the output oil and drives the steering cylinder 6 to achieve steering. The flow amplifier 5 can increase the force transmitted from the steering wheel to the steering cylinder 6, so that the driver can achieve greater steering force control with less operating force.

[0028] The S port of the plunger pump 2 is the inlet, the B port is the outlet, and the X port is the load-sensitive control port. The plunger pump 2 is used to extract the oil in the hydraulic oil tank 1 and sense the load pressure through the X port to adjust the output oil flow and pressure. When the load increases, the load-sensitive control will allow the plunger pump 2 to output a higher pressure and sufficient flow to drive the steering cylinder 6 to ensure smooth steering action; when the load is small, the plunger pump 2 will automatically reduce the flow and pressure to reduce energy loss.

[0029] In an illustrative embodiment, the hydraulic steering gear 4 includes: a first reversing valve 41, which is configured to close the first L oil port and the first R oil port when the steering wheel is in a neutral position, so that the first reversing valve 41 is in a closed state; when the steering wheel is in a left turn position, the first reversing valve 41 is in a state where the first L oil port is connected to the first P oil port, and the first R oil port is connected to the first T oil port; when the steering wheel is in a right turn position, the first reversing valve 41 is in a state where the first R oil port is connected to the first P oil port, and the first L oil port is connected to the first T oil port.

[0030] The first reversing valve 41 is a three-position hydraulically controlled reversing valve. When the steering wheel is in the middle position, all the oil ports of the first reversing valve 41 are closed. At this time, the first L oil port and the first R oil port cannot output oil to the flow amplifier 5, so the flow amplifier 5 is also in a closed state. At this time, the steering cylinder 6 will not act; when the steering wheel turns to the left, the valve core position of the first reversing valve 41 will be changed, so that the valve core is located in the left position. At this time, the first reversing valve 41 will make the first L oil port communicate with the first P oil port, and the first R oil port communicate with the first T oil port. As a result, the oil enters the flow amplifier 5 from the first L oil port, and the flow amplifier 5 amplifies the flow of the output oil, driving the steering cylinder 6 to turn left; when the steering wheel is turned to the right, the valve core position of the first reversing valve 41 will be changed, so that the valve core is located in the right position. At this time, the first reversing valve 41 will connect the first R oil port with the first P oil port, and the first L oil port with the first T oil port, so that the oil enters the flow amplifier 5 from the first R oil port, and the flow amplifier 5 amplifies the flow of the output oil, driving the steering cylinder 6 to turn right.

[0031] In an illustrative embodiment, the hydraulic steering gear 4 also includes: a gerotor motor 42, which is configured to be in a closed state when the steering wheel is in a middle position; when the steering wheel is in a left turn position, oil enters the gerotor motor 42 through the first reversing valve 41, so that the gerotor motor 42 assists the steering wheel to rotate to the left; when the steering wheel is in a right turn position, oil enters the gerotor motor 42 through the first reversing valve 41, so that the gerotor motor 42 assists the steering wheel to rotate to the right.

[0032] The cycloid motor 42 is a small, low-speed, high-torque hydraulic motor with an internally meshing cycloid gear. When the first reversing valve 41 provides oil to the cycloid motor 42, the internally meshing gear starts to rotate through a series of mechanical transmissions, causing the cycloid motor 42 to drive the steering wheel to rotate. Specifically, the cycloid motor 42 contains a stator and a movable blade. The stator, blades, and drive shaft divide the motor into two chambers, each of which has an oil port. When oil enters one oil port, oil exits the other. The oil entering pushes the blades to swing, thereby achieving rotational motion. Since the cycloid motor 42 has a large torque output capacity, it can effectively reduce the force required for the driver to turn the steering wheel, play a power-assisting role, and make driving easier and safer.

[0033] In an illustrative embodiment, the flow amplifier 5 includes: a second reversing valve 51 and an amplifying valve 52. The second reversing valve 51 is configured so that when oil enters the second L oil port, the second reversing valve 51 is in a state where the CL oil port is connected to the amplifying valve 52, and the CR oil port is connected to the HT oil port; when oil enters the second R oil port, the second reversing valve 51 is in a state where the CR oil port is connected to the liquid inlet of the amplifying valve 52, and the CL oil port is connected to the HT oil port; the amplifying valve 52 is configured to connect to the HP oil port and play a flow amplification role.

[0034] The second reversing valve 51 is a three-position hydraulically controlled reversing valve. When the steering wheel is in the middle position, the first L oil port and the first R oil port cannot output oil to the flow amplifier 5, that is, no oil enters the second L oil port and the second R oil port. At this time, all oil ports of the second reversing valve 51 are closed, and the steering cylinder 6 will not move. When the steering wheel turns left, the oil enters the second L oil port from the first L oil port. The oil entering the second L oil port will change the valve core position of the second reversing valve 51, so that the valve core is in the left position. At this time, the CL oil port and The amplification valve 52 is connected, and the CR oil port is connected with the HT oil port, that is, the CL oil port outputs oil and the CR oil port recovers oil, driving the steering cylinder 6 to turn left; when the steering wheel is turned right, the oil enters the second R oil port from the first R oil port, and the oil entering the second R oil port will change the valve core position of the second reversing valve 51, so that the valve core is located in the right position. At this time, the CR oil port is connected with the amplification valve 52, and the CL oil port is connected with the HT oil port, that is, the CR oil port outputs oil and the CL oil port recovers oil, driving the steering cylinder 6 to turn right.

[0035] In an illustrative embodiment, the amplifying valve 52 includes: an outer valve core 521 and an inner valve core 522 , wherein the inner valve core 522 is arranged inside the outer valve core 521 ; the inner valve core 522 is connected to the outer valve core 521 through a pipeline; and the area of ​​the outer valve core 521 is larger than that of the inner valve core 522 .

[0036] When a certain flow of oil is input to the inner valve core 522, the inner valve core 522 moves, and the oil pressure inside the inner valve core 522 is transmitted to the outer valve core 521 through the internal channel. Since the area of ​​the outer valve core 521 is larger than that of the inner valve core 522, under the same pressure, the output flow of the outer valve core 521 will be greater than the input flow of the inner valve core 522, thereby achieving flow amplification.

[0037] In an illustrative embodiment, the flow amplifier 5 also includes: a priority valve 53, the liquid inlet of the priority valve 53 is connected to the HP oil port through a pipeline; the first output oil port of the priority valve 53 is connected to the first P oil port through a pipeline, and the second output oil port of the priority valve 53 is connected to the second P oil port through a pipeline; the priority valve 53 is configured such that when the HP oil port pressure is less than a preset threshold value, the first output oil port of the priority valve 53 is connected to the HP oil port; when the HP oil port pressure is greater than the preset threshold value, the first output oil port and the second output oil port of the priority valve 53 are simultaneously connected to the HP oil port.

[0038] The priority valve 53 can adjust the valve core position according to the oil pressure of the HP oil port. When the pressure is lower than the preset threshold, the valve core of the priority valve 53 automatically opens to connect the first P oil port with the HP oil port, and the oil is preferentially supplied to the hydraulic steering gear 4. At this time, the plunger pump 2 is controlled to output a higher pressure and sufficient flow through the first LS oil port; when the pressure is higher than the preset threshold, the relief valve opens to connect the first P oil port and the second P oil port with the HP oil port at the same time, which can effectively control the pressure and flow of the system.

[0039] In an illustrative embodiment, the flow amplifier 5 includes: a first buffer valve 54 and a second buffer valve 55. The first buffer valve 54 is arranged on the pipeline between the CL oil port and the HT oil port, and the second buffer valve 55 is arranged on the pipeline between the CR oil port and the HT oil port. The first buffer valve 54 and the second buffer valve 55 are mainly used to slow down and adjust the speed and impact force of the oil, and protect the steering cylinder 6 from the influence of pressure shock and vibration. When the pressure or flow of the oil changes, the valve cores of the first buffer valve 54 and the second buffer valve 55 will move under the pressure, thereby changing the channel size between the valve core and the valve seat, so as to achieve the purpose of regulating the pressure and flow. This can not only prevent the steering cylinder 6 from being damaged due to excessive pressure, but also extend the service life of other components in the system.

[0040] Furthermore, a first one-way valve is provided on the pipeline between the CL oil port and the HT oil port, and the pipeline of the first one-way valve is arranged in parallel with the pipeline of the first buffer valve 54, and the conducting direction of the first one-way valve is from the HT oil port to the CL oil port; a second one-way valve is provided on the pipeline between the CR oil port and the HT oil port, and the pipeline of the second one-way valve is arranged in parallel with the pipeline of the second buffer valve 55, and the conducting direction of the second one-way valve is from the HT oil port to the CR oil port. The first one-way valve and the second one-way valve can provide an additional passage for the oil when the steering wheel suddenly changes direction, so as to prevent the sudden change of direction of the oil from causing a sharp rise in local pressure and causing damage to the system.

[0041] Further, the flow amplifier 5 further includes: a third buffer valve 56, which is arranged on the pipeline between the second LS oil port and the HT oil port. The function of the third buffer valve 56 is the same as that of the first buffer valve 54 and the second buffer valve 55, which will not be described in detail here.

[0042] In an illustrative embodiment, the plunger pump 2 includes: a hydraulic pump 21 and a load-sensing valve 22, the hydraulic pump 21 is configured to extract oil from the hydraulic oil tank 1; the load-sensing valve 22 is configured to adjust the output power of the hydraulic pump 21 according to the oil pressure of the X oil port.

[0043] The hydraulic pump 21 can provide power for the circulation of oil; the load-sensitive valve 22 senses the pressure of the load through the X oil port and transmits it to the flow control valve inside the hydraulic pump 21. According to the load pressure, the flow control valve adjusts the displacement of the hydraulic pump 21, thereby changing the output oil flow and pressure, so that the outlet pressure of the hydraulic pump 21 can always be higher than the load pressure by a fixed pressure difference.

[0044] In an illustrative embodiment, the full hydraulic load-sensitive steering system further includes: a filter 3, which is arranged on the connecting pipeline between the B oil port of the plunger pump 2 and the HP oil port of the flow amplifier 5. The filter 3 is used to remove impurities in the oil, such as particles, dust, metal chips, etc., which may damage the plunger pump 2, the flow amplifier 5 and other components of the entire hydraulic system, resulting in performance degradation, failure or even damage. By removing impurities in the oil, the filter 3 can protect the plunger pump 2, the flow amplifier 5 and other precision components in the system from damage, extend the service life of the components, and improve the reliability and stability of the system.

[0045] In an illustrative embodiment, the steering cylinder 6 includes a left steering cylinder and a right steering cylinder, the rod chamber of the left steering cylinder and the rodless chamber of the right steering cylinder are connected to the CL oil port; the rod chamber of the right steering cylinder and the rodless chamber of the left steering cylinder are connected to the CR oil port. When the CL oil port is filled with liquid, the CR oil port returns liquid, causing the left steering cylinder to retract and the right steering cylinder to extend, completing the left turn; when the CR oil port is filled with liquid, the CL oil port returns liquid, causing the right steering cylinder to retract and the left steering cylinder to extend, completing the right turn.

[0046] Based on the full hydraulic load-sensing steering system provided in the above embodiment, the second aspect of the present application further provides a coal truck, including the full hydraulic load-sensing steering system in the above embodiment. Since the coal truck provided in this embodiment has the full hydraulic load-sensing steering system provided in any of the above embodiments, the coal truck has all the beneficial effects of the full hydraulic load-sensing steering system provided in any of the above embodiments, which will not be described in detail here.

[0047] In the description of the present application, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the feature. In the description of the present application, "plurality" means two or more, unless otherwise clearly and specifically defined.

[0048] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0049] In the present application, unless otherwise clearly specified and limited, when a first feature is “on” or “below” a second feature, it may be that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, when a first feature is “above”, “above” or “above” a second feature, it may be that the first feature is directly above or obliquely above the second feature, or it may simply mean that the first feature is higher in level than the second feature. When a first feature is “below”, “below” or “below” a second feature, it may be that the first feature is directly below or obliquely below the second feature, or it may simply mean that the first feature is lower in level than the second feature.

[0050] In the description of this specification, the description of the terms "one embodiment", "some embodiments", "embodiment", "exemplary embodiment", "example", "specific example" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.

[0051] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in the field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A fully hydraulic load-sensing steering system, characterized in that: include: A hydraulic steering gear (4) is connected to the steering wheel; a first P oil port of the hydraulic steering gear (4) is connected to a second P oil port of the flow amplifier (5) via a pipeline; a first T oil port of the hydraulic steering gear (4) is connected to a second T oil port of the flow amplifier (5) via a pipeline; a first L oil port of the hydraulic steering gear (4) is connected to a second L oil port of the flow amplifier (5) via a pipeline; a first R oil port of the hydraulic steering gear (4) is connected to a second R oil port of the flow amplifier (5) via a pipeline; a first LS oil port of the hydraulic steering gear (4) is connected to a second LS oil port of the flow amplifier (5) via a pipeline; The S oil port of the plunger pump (2) is connected to the hydraulic oil tank (1) through a pipeline; the B oil port of the plunger pump (2) is connected to the HP oil port of the flow amplifier (5) through a pipeline; the X oil port of the plunger pump (2) is connected to the second LS oil port of the flow amplifier (5) through a pipeline; The HT oil port of the flow amplifier (5) is connected to the hydraulic oil tank (1) via a pipeline; The steering cylinder (6) is respectively connected to the CL oil port and the CR oil port of the flow amplifier (5) through pipelines.

2. A fully hydraulic load-sensing steering system as claimed in claim 1, characterized in that: The hydraulic steering gear (4) comprises: a first reversing valve (41), wherein the first reversing valve (41) is configured to close the first L oil port and the first R oil port when the steering wheel is in a middle position, so that the first reversing valve (41) is in a closed state; When the steering wheel is in a left-turn position, the first reversing valve (41) is in a state where the first L oil port is in communication with the first P oil port, and the first R oil port is in a state where the first T oil port is in communication with each other; When the steering wheel is in the right-turn position, the first reversing valve (41) is in a state where the first R oil port is connected to the first P oil port, and the first L oil port is connected to the first T oil port.

3. A fully hydraulic load-sensing steering system as claimed in claim 2, characterized in that: The hydraulic steering gear (4) further comprises: a cycloidal motor (42), wherein the cycloidal motor (42) is configured such that when the steering wheel is in a neutral position, the cycloidal motor (42) is in a closed state; When the steering wheel is in a left-turn position, oil enters the cycloid motor (42) through the first reversing valve (41), so that the cycloid motor (42) assists the steering wheel in rotating leftward; When the steering wheel is in the right-turn position, oil enters the cycloid motor (42) through the first reversing valve (41), causing the cycloid motor (42) to assist the steering wheel in rotating to the right.

4. A fully hydraulic load-sensing steering system as claimed in claim 1, characterized in that: The flow amplifier (5) comprises: a second reversing valve (51) and an amplifying valve (52); the second reversing valve (51) is configured such that when oil enters the second L oil port, the second reversing valve (51) is in a state where the CL oil port is in communication with the amplifying valve (52), and the CR oil port is in a state where the HT oil port is in communication with the CR oil port; When oil enters the second R oil port, the second reversing valve (51) is in a state where the CR oil port is in communication with the inlet of the amplifying valve (52), and the CL oil port is in communication with the HT oil port; The amplifying valve (52) is configured to communicate with the HP oil port and play a role in flow amplification.

5. A fully hydraulic load-sensing steering system as claimed in claim 4, characterized in that: The amplifying valve (52) comprises: an outer valve core (521) and an inner valve core (522); the inner valve core (522) is arranged inside the outer valve core (521); the inner valve core (522) is connected to the outer valve core (521) via a pipeline; the outer valve core (521) has a larger area than the inner valve core (522).

6. A fully hydraulic load sensing steering system as claimed in claim 4, characterized in that: The flow amplifier (5) further comprises: a priority valve (53), wherein a liquid inlet of the priority valve (53) is connected to the HP oil port via a pipeline; a first oil output port of the priority valve (53) is connected to the first P oil port via a pipeline, and a second oil output port of the priority valve (53) is connected to the second P oil port via a pipeline; The priority valve (53) is configured such that when the pressure of the HP oil port is less than a preset threshold, the first oil output port of the priority valve (53) is connected to the HP oil port; when the pressure of the HP oil port is greater than the preset threshold, the first oil output port and the second oil output port of the priority valve (53) are simultaneously connected to the HP oil port.

7. A fully hydraulic load sensing steering system as claimed in claim 1, characterized in that: The flow amplifier (5) comprises: a first buffer valve (54) and a second buffer valve (55), wherein the first buffer valve (54) is arranged on the pipeline between the CL oil port and the HT oil port, and the second buffer valve (55) is arranged on the pipeline between the CR oil port and the HT oil port.

8. A fully hydraulic load sensing steering system as claimed in claim 1, characterized in that: The plunger pump (2) comprises: a hydraulic pump (21) and a load-sensing valve (22); the hydraulic pump (21) is configured to extract oil from a hydraulic oil tank (1); The load sensing valve (22) is configured to adjust the output power of the hydraulic pump (21) according to the oil pressure of the X oil port.

9. A fully hydraulic load sensing steering system as claimed in claim 1, characterized in that: Also includes: A filter (3), wherein the filter (3) is arranged on a connecting pipeline between the B oil port of the plunger pump (2) and the HP oil port of the flow amplifier (5).

10. A coal transport vehicle, characterized in that: include: A fully hydraulic load-sensing steering system as claimed in any one of claims 1 to 9.

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