Multi-way valves, hydraulic systems and construction machinery

Abstract

The present disclosure provides a multi-way valve, a hydraulic system, and an engineering machine. The multi-way valve has an oil inlet port and a first oil return port. The multi-way valve includes: a working link, including a working link valve body, a main valve core, and a proportional valve. A calibration oil channel is provided inside the working link valve body, and the proportional valve is configured to drive the main valve core to move relative to the working link valve body; a state switching valve, in which, in the first working position of the state switching valve, the first end of the calibration oil channel is connected to the oil inlet port, and the second end of the calibration oil channel is connected to the first oil return port; and a control device, configured to apply a current signal to the proportional valve, drive the main valve core to move relative to the working link valve body to cut off the calibration oil channel, and obtain the current value of the current signal when the pressure at the first end of the calibration oil channel of the proportional valve begins to rise as the opening current of the proportional valve. The present disclosure can improve the control accuracy of the actuator of the engineering machine by calibrating the proportional valve in the multi-way valve.

Description

Technical Field

[0001] The present disclosure relates to the field of hydraulic technology, and in particular to a multi-way valve, a hydraulic system and engineering machinery. Background Art

[0002] At present, various types of engineering machinery need to control multiple actuators. The hydraulic systems of these engineering machinery generally use plate-type multi-way valves to provide oil for each actuator. With the development of science and technology, electrical components tend to be mature, and plate-type multi-way valves tend to adopt electro-hydraulic proportional control.

[0003] A slab-type multi-way valve is typically composed of a number of directional valve units. Different combinations of the slabs achieve a variety of operational objectives. These valves consist of an inlet section, a working section, and a tail section. Proportional valves are integrated on both sides of the working section. Control current is input to the proportional valves, which then output pilot oil, pushing the main valve core in the working section and controlling the flow and direction of the oil in the actuator. These valves can achieve proportional control of oil flow and pressure using control signals, simplifying hydraulic systems and enabling remote and automated control.

[0004] However, the manufacturing, assembly and use processes of the proportional valve may affect its control accuracy, thereby affecting the accuracy of the actuator's action. Summary of the Invention

[0005] The present disclosure aims to provide a multi-way valve capable of improving the control accuracy of an actuator of an engineering machine by calibrating a proportional valve in the multi-way valve.

[0006] A first aspect of the present disclosure provides a multi-way valve having an oil inlet port and a first oil return port, the multi-way valve comprising:

[0007] a working link configured to switch the movement direction of an actuator in a hydraulic system, the working link comprising a working link valve body, a main valve core, and a proportional valve; a calibration oil passage is provided inside the working link valve body; the proportional valve is configured to drive the main valve core to move relative to the working link valve body to connect or disconnect the calibration oil passage; the working link valve body has a first oil inlet, the first oil inlet of the working link valve body being configured to supply oil to the actuator, and the oil inlet port being in communication with the first oil inlet of the working link valve body;

[0008] a state switching valve having a first working position, in which a first end of the calibration oil passage is in communication with the oil inlet port, and a second end of the calibration oil passage is in communication with the first oil return port; and

[0009] A control device is connected to the proportional valve signal and is configured to apply a current signal to the proportional valve, drive the main valve core to move relative to the working valve body to cut off the calibrated oil channel, and obtain the current value of the current signal when the pressure at the first end of the calibrated oil channel of the proportional valve begins to rise as the opening current of the proportional valve.

[0010] According to some embodiments of the present disclosure, the state switching valve also has a second working position. In the second working position of the state switching valve, the second end of the calibrated oil channel is disconnected from the first oil return port, and the oil inlet port and the first oil return port are disconnected.

[0011] According to some embodiments of the present disclosure, the state switching valve also has a third working position. In the third working position of the state switching valve, the second end of the calibrated oil channel is disconnected from the first oil return port, and the oil inlet port is connected to the first oil return port through a damping hole.

[0012] According to some embodiments of the present disclosure,

[0013] The state switching valve has a first oil inlet, a first oil outlet, a second oil inlet, and a second oil outlet, the first oil inlet of the state switching valve being connected to the oil inlet port, the first oil outlet of the state switching valve being connected to the first oil return port, the second oil inlet of the state switching valve being connected to the second end of the calibration oil passage, and the second oil outlet of the state switching valve being connected to the first oil return port;

[0014] In the first working position of the state switching valve, the first oil inlet of the state switching valve is connected to the first oil outlet of the state switching valve through a damping hole, and the second oil inlet of the state switching valve is connected to both the first oil outlet of the state switching valve and the second oil outlet of the state switching valve;

[0015] In the second working position of the state switching valve, the first oil inlet of the state switching valve is disconnected from the first oil outlet of the state switching valve, and the second oil inlet of the state switching valve is disconnected from the second oil outlet of the state switching valve;

[0016] In the third working position of the state switching valve, the first oil inlet of the state switching valve is connected to the first oil outlet of the state switching valve through the damping hole, and the second oil inlet of the state switching valve is disconnected from the second oil outlet of the state switching valve.

[0017] According to some embodiments of the present disclosure, the multi-way valve further includes a pressure reducing valve disposed between the oil inlet port and the calibrated oil passage.

[0018] According to some embodiments of the present disclosure, the multi-way valve further includes:

[0019] an accumulator connected to the oil outlet of the pressure reducing valve and configured to supply oil to the proportional valve; and

[0020] A one-way valve, wherein the oil inlet of the one-way valve is connected to the oil outlet of the pressure reducing valve, and the oil outlet of the one-way valve is connected to the accumulator.

[0021] According to some embodiments of the present disclosure, the multi-way valve further includes a pressure detection device, which is configured to detect the pressure at the first end of the calibration oil channel.

[0022] According to some embodiments of the present disclosure,

[0023] The working valve body has a first working port and a second working port, and the main valve core has a first working position, a second working position and a third working position;

[0024] In the first working position of the main valve core, the calibration oil passage is disconnected, the oil inlet port is communicated with the first working port of the working joint valve body, and the first oil return port is communicated with the second working port of the working joint valve body;

[0025] In the second working position of the main valve core, the calibration oil passage is connected, the oil inlet port is disconnected from the first working port of the working joint valve body and the second working port of the working joint valve body, and the first oil return port is disconnected from the first working port of the working joint valve body and the second working port of the working joint valve body;

[0026] In the third working position of the main valve core, the calibration oil channel is disconnected, the oil inlet port is communicated with the second working port of the working valve body, and the first oil return port is communicated with the first working port of the working valve body.

[0027] According to some embodiments of the present disclosure,

[0028] The working joint valve body also has a first oil inlet, a first oil outlet, a second oil inlet, a second oil outlet, a third working port, a fourth working port, a third oil inlet and a third oil outlet;

[0029] The multi-way valve further has a load-sensing port, and the working link further includes a pressure-compensating valve, the pressure-compensating valve having an oil inlet, a first oil outlet, a second oil outlet, a first hydraulic control end, and a second hydraulic control end, the first hydraulic control end of the pressure-compensating valve being connected to the load-sensing port and the first oil outlet of the pressure-compensating valve;

[0030] The first oil inlet of the working valve body is connected to the oil inlet port, the first oil outlet of the working valve body is connected to the oil inlet of the pressure compensating valve and the second hydraulic control end of the pressure compensating valve, the second oil inlet of the working valve body is connected to the second oil outlet of the pressure compensating valve, the second oil outlet of the working valve body is connected to the first oil return port, the third working port of the working valve body is connected to the first working port of the working valve body, the fourth working port of the working valve body is connected to the second working port of the working valve body, the third oil inlet of the working valve body is connected to the first end of the calibration oil channel, and the third oil outlet of the working valve body is connected to the second end of the calibration oil channel.

[0031] According to some embodiments of the present disclosure, the multi-way valve further has a second oil return port, and the multi-way valve further includes a relief valve and a pressure filter valve arranged in parallel between the load sensing port and the second oil return port.

[0032] According to some embodiments of the present disclosure,

[0033] The main valve core has a first hydraulic control end and a second hydraulic control end, the proportional valve includes a first proportional valve and a second proportional valve, and the multi-way valve further has a third oil return port;

[0034] The first proportional valve has a first oil port, a second oil port, a working port, and a control end. The first oil port of the first proportional valve is connected to the third oil return port, the second oil port of the first proportional valve is connected to the oil inlet port, the working port of the first proportional valve is connected to the first hydraulic control end of the main valve core, and the control end of the first proportional valve is signal-connected to the control device and is configured to connect the second oil port of the first proportional valve and the working port of the first proportional valve according to the current signal applied by the control device, so as to switch the main valve core from the first working position to the second working position.

[0035] The second proportional valve has a first oil port, a second oil port, a working port and a control end. The first oil port of the second proportional valve is connected to the third oil return port, the second oil port of the second proportional valve is connected to the oil inlet port, the working port of the second proportional valve is connected to the second hydraulic control end of the main valve core, and the control end of the second proportional valve is connected to the control device signal and is configured to connect the second oil port of the second proportional valve and the working port of the second proportional valve according to the current signal applied by the control device to switch the main valve core from the third working position to the second working position.

[0036] According to some embodiments of the present disclosure, a plurality of the working links are arranged side by side and the calibrated oil passages of the working links are connected in series.

[0037] According to some embodiments of the present disclosure, the multi-way valve further includes a calibration button, which is connected to the state switching valve signal and is configured to send a control signal to the state switching valve to place the state switching valve in a first working position.

[0038] In the multi-way valve provided by the present disclosure, in the first working position of the state switching valve, if the calibration oil channel is connected, the oil inlet port is connected to the first oil return port, and if the calibration oil channel is cut off, the oil inlet port is disconnected from the first oil return port. When the control device applies a current signal of a certain current value to the proportional valve and causes the main valve core to move relative to the working joint valve body, the first end and the second end of the calibration oil channel can be switched from a connected state to a disconnected state, and then the pressure at the first end of the calibration oil channel begins to increase. At this time, the current value of the current signal can be used as the opening current of the proportional valve, thereby realizing the calibration of the proportional valve in the multi-way valve. After calibration, the multi-way valve can realize precise control of different proportional valves in different working joints according to the opening current of each proportional valve, and the dead zone of the operating device is smaller, thereby improving the accuracy of the action of the actuator in the engineering machinery, and eliminating the need for a large number of calibration tests, which is conducive to saving manpower and material resources and reducing costs.

[0039] A second aspect of the present disclosure provides a hydraulic system, comprising:

[0040] Hydraulic oil tank;

[0041] a hydraulic pump, wherein the oil inlet of the hydraulic pump is connected to the hydraulic oil tank;

[0042] Actuators; and

[0043] The multi-way valve described in the first aspect of the present disclosure, wherein the oil inlet port is connected to the oil outlet of the hydraulic pump, the first oil return port is connected to the hydraulic oil tank, the actuator is connected to the working link, and the working link is configured to switch the movement direction of the actuator.

[0044] The hydraulic system provided by the present disclosure has the advantages of the multi-way valve provided by the present disclosure.

[0045] A third aspect of the present disclosure provides an engineering machine, comprising the hydraulic system described in the second aspect of the present disclosure.

[0046] The engineering machinery provided by the present disclosure has the advantages of the hydraulic system provided by the present disclosure.

[0047] Other features and advantages of the present disclosure will become apparent from the following detailed description of exemplary embodiments of the present disclosure with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] The drawings described herein are used to provide a further understanding of the present disclosure and constitute a part of this application. The illustrative embodiments of the present disclosure and their descriptions are used to explain the present disclosure and do not constitute an improper limitation of the present disclosure. In the drawings:

[0049] Figure 1 The hydraulic principle diagram of the hydraulic system of some embodiments of the present disclosure.

[0050] Figure 2 This is a hydraulic principle diagram of the oil inlet connection and one of the working connections of a multi-way valve in some embodiments of the present disclosure, which shows the actuators corresponding to the hydraulic oil tank and the working connection.

[0051] Figure 3 Schematic diagram of the structure of a multi-way valve according to some embodiments of the present disclosure.

[0052] Figure 4 for Figure 3 The multi-way valve shown is a schematic cross-sectional structural diagram perpendicular to the arrangement direction of each working link.

[0053] Figure 5 for Figure 4 The cross section of the multi-way valve shown is a partially enlarged schematic diagram at point I.

[0054] Figure 6 for Figure 3 The multi-way valve shown is a schematic cross-sectional structural diagram along the arrangement direction of each working link. DETAILED DESCRIPTION

[0055] The following will be combined with the drawings in the embodiments of the present disclosure to clearly and completely describe the technical solutions in the embodiments of the present disclosure. Obviously, the described embodiments are only part of the embodiments of the present disclosure, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is in no way intended to limit the present disclosure and its application or use. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present disclosure.

[0056] Unless otherwise specifically stated, the relative arrangement of the parts and steps, the numerical expressions and the numerical values ​​set forth in these embodiments do not limit the scope of the present disclosure. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the drawings are not drawn according to actual proportional relationships. The techniques, methods and equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, the techniques, methods and equipment should be considered as part of the authorization specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as being merely exemplary and not as limitations. Therefore, other examples of the exemplary embodiments may have different values. It should be noted that similar numbers and letters represent similar items in the following figures, and therefore, once an item is defined in one figure, it does not need to be further discussed in subsequent figures.

[0057] In the description of the present disclosure, it should be understood that the use of words such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. Unless otherwise stated, the above words have no special meaning and therefore cannot be understood as limiting the scope of protection of the present disclosure.

[0058] In the description of the present disclosure, it should be understood that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "horizontal, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present disclosure and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present disclosure; the directional words "inside and outside" refer to the inside and outside relative to the outline of each component itself.

[0059] In the process of realizing the present disclosure, the inventors discovered that in the related art, the proportional electromagnets used in multi-way valves still have the following problems: the consistency of mass production of proportional electromagnets is difficult to control, and the processing, manufacturing and assembly process of the proportional valves may affect their control accuracy. There may be deviations in the opening current when each proportional valve outputs the pilot pressure, resulting in the valve core of the multi-way valve being unable to operate according to the preset current signal. In addition, after the proportional valve has been used for a period of time, a certain degree of signal attenuation will occur, causing the overall control curve of the proportional valve to shift. The above problems ultimately lead to a difference between the actual current characteristic curve of the electromagnet and the ideal current characteristic curve, resulting in deviations in the process of driving the main valve core, affecting the accuracy of the action of the actuator.

[0060] However, multi-way valves used in mobile construction machinery such as excavators, loaders, graders, backhoe loaders, and forklifts generally lack automatic calibration. The control curves for the proportional valves in these multi-way valves typically use curves specified in the manufacturer's catalog or the factory test data curves of the first multi-way valve. The controller controls the actuators based on the control curves pre-programmed into the control program, which compromises control accuracy and, consequently, the precision of the actuators' movements. Furthermore, calibrating the multi-way valves individually for multiple pieces of construction machinery is labor-intensive and wastes both human and material resources.

[0061] To improve the above problems, Figures 1 to 6 As shown, some embodiments of the present disclosure provide a multi-way valve having an oil inlet port P and a first oil return port T1 , and the multi-way valve includes a working link 2 , a state switching valve 11 and a control device.

[0062] The working link 2 is configured to switch the movement direction of the actuator 5 in the hydraulic system. Figure 1 and Figure 2 In the illustrated embodiment, the actuator 5 may be a hydraulic cylinder, and the working link 2 is configured to switch the hydraulic cylinder's movement direction. In some embodiments not shown, the actuator may also be a hydraulic motor, and the working link 2 is configured to switch the hydraulic motor's rotation direction. Multiple working links 2 may be provided to drive different actuators.

[0063] The working unit 2 includes a working unit valve body 20, a main valve core 21, and a proportional valve. A calibration oil passage C is provided within the working unit valve body 20. The proportional valve is configured to drive the main valve core 21 relative to the working unit valve body 20 to open or close the calibration oil passage C. The working unit valve body 20 has a first oil inlet Pa, which is configured to supply oil to the actuator. The oil inlet port P communicates with the first oil inlet Pa of the working unit valve body 20 to supply oil to the actuator 5 through the first oil inlet Pa of the working unit valve body 20.

[0064] like Figures 4 to 6 As shown, in each working link 2 , a portion of the calibration oil passage C may be opened on the working link valve body 20 , and the other portion may be opened on the main valve core 21 .

[0065] The state switching valve 11 has a first working position. In the first working position of the state switching valve 11 , the first end of the calibration oil passage C is connected to the oil inlet port P, and the second end of the calibration oil passage C is connected to the first oil return port T1 .

[0066] The control device is connected to the proportional valve signal. The control device is configured to apply a current signal to the proportional valve, drive the main valve core 21 to move relative to the working valve body 20 to cut off the calibrated oil channel C, and obtain the current value of the current signal when the pressure at the first end of the calibrated oil channel C of the proportional valve begins to rise as the opening current of the proportional valve.

[0067] In the multi-way valve provided in the embodiment of the present disclosure, the first working position of the state switching valve 11 can correspond to the calibration state of the multi-way valve. In the first working position of the state switching valve 11, if the calibration oil channel C is connected, the oil inlet port P is connected to the first oil return port T1, and if the calibration oil channel C is disconnected, the oil inlet port P is disconnected from the first oil return port T1. When the control device applies a current signal of a certain current value to the proportional valve and causes the main valve core 21 to move relative to the working joint valve body 20, the first and second ends of the calibration oil channel C can be switched from a connected state to a disconnected state, and the pressure at the first end of the calibration oil channel C begins to increase. At this time, the current value of the current signal can be used as the opening current of the proportional valve, thereby achieving calibration of the proportional valves in the multi-way valve. After calibration, the multi-way valve can achieve precise control of different proportional valves in different working joints based on the opening current of each proportional valve, and the dead zone of the operating device is smaller, thereby improving the accuracy of the action of the actuator in the engineering machinery and eliminating the need for a large number of calibration tests, which helps save manpower and material resources and reduce costs.

[0068] In some embodiments, as Figure 1 and Figure 2 As shown, the state switching valve 11 also has a second working position. In the second working position of the state switching valve 11, the second end of the calibration oil channel C is disconnected from the first oil return port T1, and the oil inlet port P is disconnected from the first oil return port T1.

[0069] The second working position of the state switching valve 11 can correspond to the normal working state of the multi-way valve. In the second working position of the state switching valve 11, the oil inlet port P and the calibration oil channel C are both disconnected from the first oil return port T1. When the oil inlet port P is connected to the hydraulic pump, the oil inlet port P can be used to supply oil to the actuator 5 corresponding to the working link 2, and the construction machinery can drive the actuator 5 to move through the multi-way valve.

[0070] In some embodiments, as Figure 1 and Figure 2 As shown, the state switching valve 11 also has a third working position. In the third working position of the state switching valve 11, the second end of the calibration oil channel C is disconnected from the first oil return port T1, and the oil inlet port P is connected to the first oil return port T1 through the damping hole.

[0071] The third working position of the state switching valve 11 can correspond to the standby state of the multi-way valve. In the third working position of the state switching valve 11, the oil inlet port P is connected to the first oil return port T1 through the damping hole. When the oil inlet port P is connected to the hydraulic pump, the hydraulic oil output by the hydraulic pump returns to the hydraulic oil tank through the oil inlet port P, the damping hole and the first oil return port T1. The hydraulic pump can only retain the standby pressure. When the engineering machinery is ignited and on standby, energy consumption can be saved by placing the state switching valve 11 in the third working position.

[0072] The state switching valve 11 can be a solenoid valve connected to a control device signal, and the working position is changed by a control signal sent by the control device; or it can be a manual valve, and the working position is changed manually by an operator.

[0073] In some embodiments, as Figure 1 and Figure 2 As shown, the state switching valve 11 has a first oil inlet Pd, a first oil outlet Td, a second oil inlet Pe and a second oil outlet Te. The first oil inlet Pd of the state switching valve 11 is connected to the oil inlet port P, the first oil outlet Td of the state switching valve 11 is connected to the first oil return port T1, the second oil inlet Pe of the state switching valve 11 is connected to the second end of the calibration oil channel C, and the second oil outlet Te of the state switching valve 11 is connected to the first oil return port T1. In the first working position of the state switching valve 11, the first oil inlet Pd of the state switching valve 11 is connected to the first oil outlet Td of the state switching valve 11 through the damping hole, and the second oil inlet Pe of the state switching valve 11 is connected to the first oil outlet Td of the state switching valve 11 and the second oil outlet Te of the state switching valve 11; in the second working position of the state switching valve 11, the first oil inlet Pd of the state switching valve 11 is disconnected from the first oil outlet Td of the state switching valve 11, and the second oil inlet Pe of the state switching valve 11 is disconnected from the second oil outlet Te of the state switching valve 11; in the third working position of the state switching valve 11, the first oil inlet Pd of the state switching valve 11 is connected to the first oil outlet Td of the state switching valve 11 through the damping hole, and the second oil inlet Pe of the state switching valve 11 is disconnected from the second oil outlet Te of the state switching valve 11.

[0074] When the proportional valve drives the main valve core 21 to move under the action of the current signal, the oil inlet port P will be connected to the actuator 5. In this embodiment, when the state switching valve 11 is in the first working position, that is, when the proportional valve in the multi-way valve needs to be calibrated, the first oil inlet port Pd of the state switching valve 11 is connected to the first oil outlet port Td of the state switching valve 11 through the damping orifice. When the oil inlet port P is connected to the hydraulic pump, the hydraulic oil output by the hydraulic pump is unloaded to the hydraulic oil tank 4 through the oil inlet port P, the damping orifice, and the first oil return port T1, leaving only a lower pressure for supplying oil to the calibration oil channel C. The pressure at the oil inlet port P is insufficient to drive the actuator 5. This makes the calibration process safer and more reliable.

[0075] In a multi-way valve, the pressure required to drive the actuator 5 of the multi-way valve is higher, while the pressure required to drive the main valve core 21 and the pressure required for the calibration oil channel C are lower. The oil inlet port P is usually connected to the high-pressure oil source required to drive the actuator 5. In order to convert the high-pressure oil from the oil inlet port P into low-pressure oil, in some embodiments, such as Figure 1 As shown, the multi-way valve further includes a pressure reducing valve 33 disposed between the oil inlet port P and the calibration oil channel C. In some embodiments not shown, a low-pressure oil source may be provided outside the multi-way valve, and a separate port for connecting to the low-pressure oil source may be provided on the multi-way valve.

[0076] In some embodiments, the multi-way valve further includes an accumulator 32 and a one-way valve 34. The accumulator 32 is connected to the oil outlet of the pressure reducing valve 33 and is configured to supply oil to the proportional valve. The oil inlet of the one-way valve 34 is connected to the oil outlet of the pressure reducing valve 33, and the oil outlet of the one-way valve 34 is connected to the accumulator 32.

[0077] In this embodiment, the one-way valve 34 is arranged between the oil outlet of the pressure reducing valve 33 and the accumulator 32 and is unidirectionally conducted from the pressure reducing valve 33 to the accumulator 32. The oil inlet port P can supply oil to the accumulator 32 through the pressure reducing valve 33. When the state switching valve 11 is in the first working position, it can also prevent the pilot oil stored in the accumulator 32 from leaking back to the hydraulic oil tank 4 through the calibrated oil channel C, thereby ensuring that the accumulator 32 can normally supply oil to the proportional valve.

[0078] In some embodiments, the multi-way valve further includes a pressure detection device 31 , which is configured to detect the pressure at the first end of the calibration oil channel C.

[0079] In some embodiments, as Figure 1 and Figure 2As shown, the working valve body 20 has a first working port A and a second working port B, and the main valve core 21 has a first working position, a second working position and a third working position. In the first working position of the main valve core 21, the calibration oil channel C is disconnected, the oil inlet port P is connected to the first working port A of the working valve body 20, and the first oil return port T1 is connected to the second working port B of the working valve body 20. At this time, the first working port A of the working valve body 20 is filled with oil and the second working port B of the working valve body 20 is discharged with oil; in the second working position of the main valve core 21, the calibration oil channel C is connected, the oil inlet port P is disconnected from both the first working port A of the working valve body 20 and the second working port B of the working valve body 20, and the first oil return port T1 is disconnected from both the first working port A of the working valve body 20 and the second working port B of the working valve body 20; in the third working position of the main valve core 21, the calibration oil channel C is disconnected, the oil inlet port P is connected to the second working port B of the working valve body 20, and the first oil return port T1 is connected to the first working port A of the working valve body 20. At this time, the first working port A of the working valve body 20 is discharged with oil and the second working port B of the working valve body 20 is filled with oil.

[0080] In some embodiments, as Figure 2 As shown, the working valve body 20 further comprises a first oil inlet Pa, a first oil outlet Ta, a second oil inlet Pb, a second oil outlet Tb, a third working port A1, a fourth working port B1, a third oil inlet Pc, and a third oil outlet Tc. The multi-way valve further comprises a load-sensing port LS. The working valve 20 also includes a pressure-compensating valve 22, which comprises an oil inlet Ph, a first oil outlet Th, a second oil outlet Ti, a first hydraulic control port K5, and a second hydraulic control port K6. The first hydraulic control port K5 of the pressure-compensating valve 22 is connected to the load-sensing port LS and the first oil outlet Th of the pressure-compensating valve 22. The first oil inlet Pa of the working joint valve body 20 is connected to the oil inlet port P, the first oil outlet Ta of the working joint valve body 20 is connected to the oil inlet Ph of the pressure compensating valve 22 and the second hydraulic control port K6 of the pressure compensating valve 22, the second oil inlet Pb of the working joint valve body 20 is connected to the second oil outlet Ti of the pressure compensating valve 22, the second oil outlet Tb of the working joint valve body 20 is connected to the first oil return port T1, the third working port A1 of the working joint valve body 20 is connected to the first working port A of the working joint valve body 20, the fourth working port B1 of the working joint valve body 20 is connected to the second working port B of the working joint valve body 20, the third oil inlet Pc of the working joint valve body 20 is connected to the first end of the calibration oil channel C, and the third oil outlet Tc of the working joint valve body 20 is connected to the second end of the calibration oil channel C. In this embodiment, the provision of the pressure compensating valve 22 in the working joint 2 can rationally distribute the flow of the hydraulic pump to the actuator 5 corresponding to each working joint 2.

[0081] In some embodiments, as Figure 1 and Figure 2As shown, the multi-way valve also has a second oil return port T2. The multi-way valve also includes a relief valve 12 and a pressure filter valve 13, which are arranged in parallel between the load sensing port LS and the second oil return port T2. The relief valve 12 can keep the pressure of the load sensing feedback oil circuit below the safety pressure, and the pressure filter valve 13 can alleviate pressure fluctuations in the load sensing feedback oil circuit.

[0082] In some embodiments, as Figure 2 As shown, the main valve core 21 has a first hydraulic control end K3 and a second hydraulic control end K4. The proportional valve includes a first proportional valve 23a and a second proportional valve 23b. The multi-way valve further has a third oil return port T3. The first proportional valve 23a has a first oil port Tf, a second oil port Pf, a working port W1, and a control end K1. The first oil port Tf of the first proportional valve 23a is connected to the third oil return port T3, the second oil port Pf of the first proportional valve 23a is connected to the oil inlet port P, and the working port W1 of the first proportional valve 23a is connected to the first hydraulic control end K3 of the main valve core 21. The control end K1 of the first proportional valve 23a is signal-connected to a control device and is configured to connect the second oil port Pf of the first proportional valve 23a and the working port W1 of the first proportional valve 23a in response to a current signal applied by the control device, thereby switching the main valve core 21 from the first working position to the second working position. The second proportional valve 23b has a first oil port Tg, a second oil port Pg, a working port W2 and a control end K2. The first oil port Tg of the second proportional valve 23b is connected to the third oil return port T3, the second oil port Pg of the second proportional valve 23b is connected to the oil inlet port P, the working port W2 of the second proportional valve 23b is connected to the second hydraulic control end K4 of the main valve core 21, and the control end K2 of the second proportional valve 23b is connected to the control device signal and is configured to connect the second oil port Pg of the second proportional valve 23b and the working port W2 of the second proportional valve 23b according to the current signal applied by the control device to switch the main valve core 21 from the third working position to the second working position.

[0083] In some embodiments, as Figure 1 、 Figure 3 and Figure 6 As shown, a plurality of working links 2 are arranged side by side and the calibration oil passages C of the working links 2 are connected in series. The above-mentioned structural form facilitates the processing and assembly of the working links.

[0084] like Figure 1 、 Figure 3 、 Figure 4 and Figure 6As shown, in this embodiment, the multi-way valve may further include an oil inlet link 1 arranged on one side of the multiple working links 2 and a tail link 3 arranged on the other side of the multiple working links 2, wherein the oil inlet link 1 includes an oil inlet link valve body 10, and the oil inlet port P, the first oil return port T1, the second oil return port T2, the load sensing port LS, the state switching valve 11, the overflow valve 12 and the pressure filter valve 13 can be arranged on the oil inlet link valve body 10; the tail link 3 includes a tail link valve body 30, and the third oil return port T3, the pressure detection device 31, the accumulator 32, the pressure reducing valve 33 and the one-way valve 34 can be arranged on the tail link valve body 30, and a first oil channel C1 is provided inside the tail link valve body 30 to connect the outlet of the pressure reducing valve 33 and the first end of the calibration oil channel C.

[0085] In some embodiments, the multi-way valve further includes a calibration button, which is signal-connected to the state switching valve 11 and configured to send a control signal to the state switching valve 11 to place the state switching valve 11 in the first working position.

[0086] In this embodiment, the calibration button can also be connected to the control device signal. After the calibration button sends a control signal to place the state switching valve 11 in the first working position, the automatic calibration program stored in the control device is called to apply current proportional signals to the control end K1 of the first proportional valve 23a and the control end K2 of the second proportional valve 23b of each working link 2 in turn, thereby realizing one-button automatic calibration of each proportional valve in the multi-way valve.

[0087] The following combination Figures 1 to 6 The working principle of the multi-way valve according to some embodiments of the present disclosure is described.

[0088] When the construction machinery is ignited and on standby, the actuators 5 corresponding to the working links 2 of the multi-way valve are inactive, so that the state switching valve 11 is in the third working position. The hydraulic oil output by the hydraulic pump returns to the hydraulic oil tank 4 through the oil inlet port P, the damping hole and the first oil return port T1. The hydraulic pump only retains the standby pressure, and the excess oil is unloaded to the oil tank, saving energy consumption.

[0089] When the proportional valves in the multi-way valve need to be calibrated, after the construction machinery is powered on, the hydraulic pump automatically fills the accumulator 32 through the oil inlet port P. A control signal then switches the state switching valve 11 to its first operating position, connecting the oil inlet port P, the pressure reducing valve 33, the calibration oil passage C, and the first oil return port T1 in sequence. The pressure detection device 31 is essentially pressure-free. The control device then applies current signals to the first and second proportional valves 23a, 23b on either side of the main valve core 21 of each working link 2. At this point, the accumulator 32 supplies oil to the first and second proportional valves 23a, 23b, causing the first or second proportional valve 23a, 23b to move the main valve core 21 relative to the working link valve body 20. Calibration oil passage C is disconnected, and the pressure in the pressure detection device 31 increases. The current value of the current signal at the time the pressure in the pressure detection device 31 begins to rise is the opening current of the first or second proportional valve 23a, 23b, and this current value is recorded in the control device.

[0090] After the calibration is completed, the state switching valve is placed in the second working position. At this time, the oil inlet port P and the calibration oil channel C are disconnected from the first oil return port T1. The hydraulic pump supplies oil to the actuator 5 corresponding to the working link 2 through the oil inlet port P to drive the actuator 5 to move.

[0091] Some embodiments of the present disclosure also provide a hydraulic system comprising a hydraulic oil tank 4, a hydraulic pump, an actuator 5, and the aforementioned multi-way valve. The hydraulic pump's oil inlet is connected to the hydraulic oil tank 4. The multi-way valve's oil inlet port P is connected to the hydraulic pump's oil outlet, while its first oil return port T1 is connected to the hydraulic oil tank 4. The actuator 5 is connected to a working link 2, which is configured to switch the direction of motion of the actuator 5. Because this hydraulic system utilizes the aforementioned multi-way valve, it possesses the advantages of the aforementioned multi-way valve.

[0092] Some embodiments of the present disclosure further provide an engineering machine comprising the aforementioned hydraulic system. Due to the use of the aforementioned hydraulic system, the engineering machine has the advantages of the aforementioned hydraulic system.

[0093] In some embodiments, the control device described above can be implemented as a general-purpose processor, a programmable logic controller (PLC), a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or any appropriate combination thereof for performing the functions described in the present disclosure.

[0094] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present disclosure and are not intended to limit them. Although the present disclosure has been described in detail with reference to preferred embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present disclosure can still be modified or some technical features can be replaced by equivalents, which should all be included in the scope of the technical solutions claimed for protection in the present disclosure.

Claims

1. A multi-way valve, characterized in that: Having an oil inlet port (P) and a first oil return port (T1), the multi-way valve comprises: A working link (2) is configured to switch the movement direction of an actuator (5) in a hydraulic system, the working link (2) comprising a working link valve body (20), a main valve core (21) and a proportional valve, a calibration oil passage (C) being provided inside the working link valve body (20), the proportional valve being configured to drive the main valve core (21) to move relative to the working link valve body (20) to connect or disconnect the calibration oil passage (C), the working link valve body (20) having a first oil inlet (Pa), the first oil inlet (Pa) of the working link valve body (20) being configured to supply oil to the actuator, and the oil inlet port (P) being communicated with the first oil inlet (Pa) of the working link valve body (20); A state switching valve (11), the state switching valve (11) having a first working position and a second working position, wherein in the first working position of the state switching valve (11), the first end of the calibration oil passage (C) is communicated with the oil inlet port (P), and the second end of the calibration oil passage (C) is communicated with the first oil return port (T1), and in the second working position of the state switching valve (11), the second end of the calibration oil passage (C) is disconnected from the first oil return port (T1), and the oil inlet port (P) and the first oil return port (T1) are disconnected; and A control device is connected to the proportional valve signal and is configured to apply a current signal to the proportional valve, drive the main valve core (21) to move relative to the working valve body (20) to cut off the calibration oil channel (C), and obtain the current value of the current signal when the pressure at the first end of the calibration oil channel (C) of the proportional valve begins to rise as the opening current of the proportional valve.

2. The multi-way valve according to claim 1, characterized in that: The state switching valve (11) further has a third working position. In the third working position of the state switching valve (11), the second end of the calibration oil passage (C) is disconnected from the first oil return port (T1), and the oil inlet port (P) is connected to the first oil return port (T1) via a damping hole.

3. The multi-way valve according to claim 2, characterized in that: The state switching valve (11) has a first oil inlet (Pd), a first oil outlet (Td), a second oil inlet (Pe) and a second oil outlet (Te); the first oil inlet (Pd) of the state switching valve (11) is connected to the oil inlet port (P); the first oil outlet (Td) of the state switching valve (11) is connected to the first oil return port (T1); the second oil inlet (Pe) of the state switching valve (11) is connected to the second end of the calibration oil channel (C); and the second oil outlet (Te) of the state switching valve (11) is connected to the first oil return port (T1); In the first working position of the state switching valve (11), the first oil inlet (Pd) of the state switching valve (11) is connected to the first oil outlet (Td) of the state switching valve (11) via a damping hole, and the second oil inlet (Pe) of the state switching valve (11) is connected to both the first oil outlet (Td) of the state switching valve (11) and the second oil outlet (Te) of the state switching valve (11); In the second working position of the state switching valve (11), the first oil inlet (Pd) of the state switching valve (11) is disconnected from the first oil outlet (Td) of the state switching valve (11), and the second oil inlet (Pe) of the state switching valve (11) is disconnected from the second oil outlet (Te) of the state switching valve (11); In the third working position of the state switching valve (11), the first oil inlet (Pd) of the state switching valve (11) is connected to the first oil outlet (Td) of the state switching valve (11) through the damping hole, and the second oil inlet (Pe) of the state switching valve (11) is disconnected from the second oil outlet (Te) of the state switching valve (11).

4. The multi-way valve according to claim 1, characterized in that: It also includes a pressure reducing valve (33) arranged between the oil inlet port (P) and the calibration oil channel (C).

5. The multi-way valve according to claim 4, characterized in that: Also includes: an accumulator (32) connected to the oil outlet of the pressure reducing valve (33) and configured to supply oil to the proportional valve; and A one-way valve (34), wherein the oil inlet of the one-way valve (34) is connected to the oil outlet of the pressure reducing valve (33), and the oil outlet of the one-way valve (34) is connected to the accumulator (32).

6. The multi-way valve according to any one of claims 1 to 5, characterized in that: It also includes a pressure detection device (31), which is configured to detect the pressure at the first end of the calibration oil channel (C).

7. The multi-way valve according to any one of claims 1 to 5, characterized in that: The working valve body (20) has a first working port (A) and a second working port (B), and the main valve core (21) has a first working position, a second working position, and a third working position; In the first working position of the main valve core (21), the calibration oil passage (C) is disconnected, the oil inlet port (P) is connected to the first working port (A) of the working joint valve body (20), and the first oil return port (T1) is connected to the second working port (B) of the working joint valve body (20); In the second working position of the main valve core (21), the calibration oil passage (C) is connected, the oil inlet port (P) is disconnected from the first working port (A) of the working joint valve body (20) and the second working port (B) of the working joint valve body (20), and the first oil return port (T1) is disconnected from the first working port (A) of the working joint valve body (20) and the second working port (B) of the working joint valve body (20); In the third working position of the main valve core (21), the calibration oil passage (C) is disconnected, the oil inlet port (P) is connected to the second working port (B) of the working joint valve body (20), and the first oil return port (T1) is connected to the first working port (A) of the working joint valve body (20).

8. The multi-way valve according to claim 7, characterized in that: The working joint valve body (20) further comprises a first oil inlet (Pa), a first oil outlet (Ta), a second oil inlet (Pb), a second oil outlet (Tb), a third working port (A1), a fourth working port (B1), a third oil inlet (Pc) and a third oil outlet (Tc); The multi-way valve further comprises a load-sensing port (LS), the working link (2) further comprises a pressure-compensating valve (22), the pressure-compensating valve (22) comprises an oil inlet (Ph), a first oil outlet (Th), a second oil outlet (Ti), a first hydraulic control end (K5), and a second hydraulic control end (K6), the first hydraulic control end (K5) of the pressure-compensating valve (22) being connected to the load-sensing port (LS) and the first oil outlet (Th) of the pressure-compensating valve (22); The first oil inlet (Pa) of the working joint valve body (20) is connected to the oil inlet port (P), the first oil outlet (Ta) of the working joint valve body (20) is connected to the oil inlet (Ph) of the pressure compensation valve (22) and the second hydraulic control end (K6) of the pressure compensation valve (22), the second oil inlet (Pb) of the working joint valve body (20) is connected to the second oil outlet (Ti) of the pressure compensation valve (22), and the second oil outlet (Tb) of the working joint valve body (20) is connected to the first oil return port (K6). The working valve body (20) is connected to the first working port (A) of the working valve body (20), the fourth working port (B1) of the working valve body (20) is connected to the second working port (B) of the working valve body (20), the third oil inlet (Pc) of the working valve body (20) is connected to the first end of the calibration oil channel (C), and the third oil outlet (Tc) of the working valve body (20) is connected to the second end of the calibration oil channel (C).

9. The multi-way valve according to claim 8, characterized in that: The multi-way valve further comprises a second oil return port (T2), and a relief valve (12) and a pressure filter valve (13) which are arranged in parallel between the load sensing port (LS) and the second oil return port (T2).

10. The multi-way valve according to claim 7, characterized in that: The main valve core (21) has a first hydraulic control end (K3) and a second hydraulic control end (K4); the proportional valve includes a first proportional valve (23a) and a second proportional valve (23b); and the multi-way valve further has a third oil return port (T3); The first proportional valve (23a) has a first oil port (Tf), a second oil port (Pf), a working port (W1) and a control end (K1); the first oil port (Tf) of the first proportional valve (23a) is connected to the third oil return port (T3); the second oil port (Pf) of the first proportional valve (23a) is connected to the oil inlet port (P); the working port (W1) of the first proportional valve (23a) is connected to the first hydraulic control end (K3) of the main valve core (21); the control end (K1) of the first proportional valve (23a) is connected to the control device signal and is configured to connect the second oil port (Pf) of the first proportional valve (23a) and the working port (W1) of the first proportional valve (23a) according to the current signal applied by the control device, so as to switch the main valve core (21) from the first working position to the second working position; The second proportional valve (23b) has a first oil port (Tg), a second oil port (Pg), a working port (W2) and a control end (K2). The first oil port (Tg) of the second proportional valve (23b) is connected to the third oil return port (T3), the second oil port (Pg) of the second proportional valve (23b) is connected to the oil inlet port (P), the working port (W2) of the second proportional valve (23b) is connected to the second hydraulic control end (K4) of the main valve core (21), and the control end (K2) of the second proportional valve (23b) is connected to the control device signal and is configured to connect the second oil port (Pg) of the second proportional valve (23b) and the working port (W2) of the second proportional valve (23b) according to the current signal applied by the control device, so as to switch the main valve core (21) from the third working position to the second working position.

11. The multi-way valve according to any one of claims 1 to 5, characterized in that: The plurality of working links (2) are arranged side by side and the calibration oil passages (C) of the working links (2) are connected in series.

12. The multi-way valve according to any one of claims 1 to 5, characterized in that: It also includes a calibration button, which is connected to the state switching valve (11) signal and is configured to send a control signal to the state switching valve (11) to place the state switching valve (11) in the first working position.

13. A hydraulic system, characterized in that: include: Hydraulic oil tank (4); A hydraulic pump, wherein the oil inlet of the hydraulic pump is connected to the hydraulic oil tank (4); Actuator (5); and The multi-way valve according to any one of claims 1 to 12, wherein the oil inlet port (P) is connected to the oil outlet of the hydraulic pump, the first oil return port (T1) is connected to the hydraulic oil tank (4), the actuator (5) is connected to the working link (2), and the working link (2) is configured to switch the movement direction of the actuator (5).

14. An engineering machine, characterized in that: Comprising a hydraulic system according to claim 13.

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