Control valve, hydraulic system and concrete pumping apparatus

Abstract

The present disclosure provides a control valve, a hydraulic system and a concrete pumping device. The control valve comprises a valve body having a first oil port, a second oil port, a third oil port and a fourth oil port; and a valve cover internally provided with a first oil channel and a second oil channel, the valve cover being switchable between a first working state and a second working state; wherein in the first working state, the first oil channel communicates the first oil port and the third oil port, and the second oil channel communicates the second oil port and the fourth oil port; in the second working state, the first oil channel and / or the second oil channel communicates the third oil port and the fourth oil port, or communicates the first oil port and the second oil port. The hydraulic system comprises a first oil cylinder, a second oil cylinder, a first control valve and a second control valve, the first control valve being arranged on one side of the rod cavity and the rodless cavity of the first oil cylinder and the second oil cylinder, and the second control valve being arranged on one side of the rodless cavity of the first oil cylinder and the second oil cylinder. The concrete pumping device comprises the aforementioned control valve or hydraulic system.

Description

Technical Field

[0001] This disclosure relates to the field of hydraulic technology, and in particular to a control valve, a hydraulic system, and a concrete pumping device. Background Technology

[0002] Currently, with the widespread development of human infrastructure, large-scale concrete pumping equipment is needed for bridge construction, building houses, water conservancy projects, airport construction, and so on. To better adapt to various construction conditions (such as ultra-long-distance and ultra-high-altitude conveying) and different concrete mix proportions, large-scale concrete pumping equipment generally possesses high-low pressure switching capabilities, thereby enhancing its competitiveness. However, in related technologies, the hydraulic systems used for high-low pressure switching suffer from at least one of the following problems: complex switching process; complex system structure; large pressure loss and high oil temperature, which are detrimental to energy conservation and result in high costs. Summary of the Invention

[0003] The purpose of this disclosure is to provide a control valve, a hydraulic system, and a concrete pumping device to reduce pressure loss in the hydraulic system of the concrete pumping device.

[0004] A first aspect of this disclosure provides a control valve, comprising:

[0005] The valve body has a first port, a second port, a third port, and a fourth port for connection to a hydraulic line; and

[0006] A valve cover assembly has a first oil passage and a second oil passage inside. The valve cover assembly has a first working state and a second working state. The valve cover assembly is movably mounted on the valve body so that the valve cover assembly can switch between the first working state and the second working state.

[0007] In the first operating state, the first oil passage connects the first oil port and the third oil port, and the valve body enters through one of the first oil port and exits through the other. The second oil passage connects the second oil port and the fourth oil port, and the valve body enters through one of the second oil port and exits through the other. In the second operating state, the first oil passage and / or the second oil passage connect the third oil port and the fourth oil port, and the valve body enters through one of the third oil port and exits through the other. Alternatively, in the second operating state, the first oil passage and / or the second oil passage connect the first oil port and the second oil port, and the valve body enters through one of the first oil port and exits through the other.

[0008] According to some embodiments of this disclosure, the valve cover assembly includes:

[0009] A first valve cover, a first oil passage disposed within the first valve cover, the first valve cover being rotatably mounted on the valve body so that the first oil passage can selectively communicate with different oil ports of the valve body; and

[0010] The second valve cover has the second oil passage disposed inside it. The second valve cover is rotatably mounted on the valve body so that the second oil passage can be selectively connected to different oil ports of the valve body.

[0011] According to some embodiments of this disclosure, the first valve cover and the second valve cover are stacked sequentially on the valve body.

[0012] According to some embodiments of this disclosure

[0013] The first valve cover has a fifth oil port, a sixth oil port, a seventh oil port and an eighth oil port, and the fifth oil port and the seventh oil port are connected through the first oil passage;

[0014] The second valve cover has a ninth oil port and a tenth oil port, which are connected through the second oil passage;

[0015] In the first working state, the fifth oil port is connected to the first oil port, the sixth oil port is connected to the second oil port and the ninth oil port, the seventh oil port is connected to the third oil port, and the eighth oil port is connected to the fourth oil port and the tenth oil port.

[0016] In the second operating state, the fifth oil port is connected to the third oil port, the seventh oil port is connected to the fourth oil port, the sixth oil port and the eighth oil port are closed by the second valve cover, the first oil passage connects the third oil port and the fourth oil port, and the valve body enters oil through one of the third oil port and exits oil through the other. Alternatively, in the second operating state, the fifth oil port is connected to the second oil port, the seventh oil port is connected to the first oil port, the sixth oil port and the eighth oil port are closed by the second valve cover, the first oil passage connects the first oil port and the second oil port, and the valve body enters oil through one of the first oil port and exits oil through the other.

[0017] According to some embodiments of this disclosure, the sixth oil port and the eighth oil port penetrate the first valve cover along the stacking direction of the first valve cover and the second valve cover.

[0018] According to some embodiments of this disclosure

[0019] The first oil port, the second oil port, the fourth oil port, and the third oil port are rotationally symmetrically distributed.

[0020] The fifth, sixth, eighth, and seventh oil ports are rotationally symmetrically distributed.

[0021] According to some embodiments of this disclosure

[0022] The first valve cover has a square cross-section perpendicular to the stacking direction of the first and second valve covers, and the fifth and seventh oil ports are arranged adjacent to each other along one side of the square; and / or

[0023] The cross-section of the second valve cover perpendicular to the stacking direction of the first valve cover and the second valve cover is a square, and the ninth oil port and the tenth oil port are arranged adjacent to each other along one side of the square.

[0024] According to some embodiments of this disclosure, a first connector and a second connector are also included, the first connector and the second connector passing through the second valve cover and the first valve cover in sequence and connected to the valve body, the axis of the first connector coinciding with the rotation axis of the first valve cover and the second valve cover, and the second connector being distributed around the first connector.

[0025] According to some embodiments of this disclosure, the valve cover assembly further includes:

[0026] A first handle, disposed on the first valve cover, is configured to rotate the first valve cover; and / or

[0027] A second handle, disposed on the second valve cover, is configured to rotate the second valve cover.

[0028] A second aspect of this disclosure provides a hydraulic system comprising:

[0029] First oil cylinder;

[0030] The second hydraulic cylinder is arranged side by side with the first hydraulic cylinder;

[0031] A first control valve, as described in the first aspect of this disclosure, is disposed on one side of the rod chamber of the first and second cylinders. In the second operating state of the valve cover assembly, the first oil passage and / or the second oil passage of the first control valve connects the third oil port and the fourth oil port; and

[0032] The second control valve, which is the control valve described in the first aspect of this disclosure, is disposed on one side of the rodless chamber of the first cylinder and the second cylinder. In the second working state of the valve cover assembly, the first oil passage and / or the second oil passage of the second control valve connect the first oil port and the second oil port.

[0033] Wherein, the first oil port of the first control valve is connected to the third oil port of the second control valve, the second oil port of the first control valve is connected to the fourth oil port of the second control valve, the third oil port of the first control valve is connected to the rod chamber of the first cylinder, the fourth oil port of the first control valve is connected to the rod chamber of the second cylinder, the first oil port of the second control valve is connected to the rodless chamber of the first cylinder, and the second oil port of the second control valve is connected to the rodless chamber of the second cylinder. One of the first oil port and the second oil port of the first control valve is an oil inlet and the other is an oil outlet.

[0034] According to some embodiments of this disclosure, the hydraulic system has a low-pressure operating state and a high-pressure operating state, wherein,

[0035] In the low-pressure operating state, the valve cover assembly of the first control valve is in the first operating state, and the valve cover assembly of the second control valve is in the second operating state.

[0036] In the high-pressure operating state, the valve cover assembly of the first control valve is in the second operating state, and the valve cover assembly of the second control valve is in the first operating state.

[0037] A third aspect of this disclosure provides a concrete pumping device, including the control valve described in the first aspect of this disclosure, or including the hydraulic system described in the second aspect of this disclosure.

[0038] Based on the control valve provided by the embodiments of this disclosure, operators do not need to manually disassemble and assemble pipelines, which helps to save the workload of switching between high and low pressure; it can also reduce the number of electrical control components, reduce the complexity of the control system, and reduce manufacturing and operating costs.

[0039] The control valve and hydraulic system including the control valve provided by the embodiments of this disclosure can reduce the detours of hydraulic lines and reduce the complexity of hydraulic lines; and can reduce the length of the inlet line and the return line by at least about the length of one cylinder stroke. Considering the relatively long stroke of the main pumping cylinder, the pressure loss of hydraulic oil along the stroke can be significantly reduced, thereby reducing the fuel consumption of the concrete pumping equipment. Therefore, the manufacturing cost and operating cost of the concrete pumping equipment can be further reduced.

[0040] The concrete pumping equipment provided in this disclosure has the corresponding advantages of control valves or hydraulic systems.

[0041] Other features and advantages of this disclosure will become clear from the following detailed description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description

[0042] The accompanying drawings, which are included to provide a further understanding of this disclosure and form part of this application, illustrate exemplary embodiments of this disclosure and are used to explain this disclosure, but do not constitute an undue limitation of this disclosure. In the drawings:

[0043] Figure 1 This is a schematic diagram of the structure of a control valve according to some embodiments of this disclosure.

[0044] Figure 2 for Figure 1 The diagram shows the structure of the control valve from another perspective.

[0045] Figure 3 for Figure 1 The diagram shows the structural structure of the control valve body.

[0046] Figure 4 for Figure 3 The diagram shows the valve body from another perspective.

[0047] Figure 5 for Figure 1 The diagram shows the structure of the first valve cover of the control valve.

[0048] Figure 6 for Figure 1 The diagram shows the structure of the second valve cover of the control valve.

[0049] Figure 7 for Figure 1 The diagram shows the control valve installed on the main valve.

[0050] Figure 8 This is a schematic diagram of the structure of a control valve according to some other embodiments of this disclosure.

[0051] Figure 9 for Figure 8 The diagram shows the structural structure of the control valve body.

[0052] Figure 10 for Figure 9 The diagram shows the valve body from another perspective.

[0053] Figure 11 This is a schematic diagram of the hydraulic principle of a hydraulic system according to some embodiments of the present disclosure.

[0054] Figures 1 to 11 In the figures, the labels represent:

[0055] 1. Valve body; 11. First oil port; 12. Second oil port; 13. Third oil port; 14. Fourth oil port; 15. First mounting hole; 16. Second mounting hole; 1A. First valve body; 1B. Second valve body;

[0056] 2. Valve cover assembly; 21. First valve cover; 211. Fifth oil port; 212. Sixth oil port; 213. Seventh oil port; 214. Eighth oil port; 215. First oil passage; 216. Third mounting hole; 217. Fourth mounting hole; 22. Second valve cover; 221. Ninth oil port; 222. Tenth oil port; 223. Second oil passage; 224. Fifth mounting hole; 225. Sixth mounting hole; 23. First handle; 24. Second handle;

[0057] 3. Main valve; 31. First valve core; 32. Second valve core;

[0058] 41. First connector; 42. Second connector;

[0059] 51. First pipeline; 52. Second pipeline; 53. Third pipeline; 54. Fourth pipeline;

[0060] 61. First hydraulic cylinder; 62. Second hydraulic cylinder;

[0061] A, First working port of the main valve; B, Second working port of the main valve; P, Oil inlet of the main valve; T, Oil outlet of the main valve; XP, First control terminal of the main valve; XR, Second control terminal of the main valve; XA, Third control terminal of the main valve; XB, Fourth control terminal of the main valve;

[0062] C. First working port of the first valve body; D. Second working port of the first valve body; E. Third working port of the first valve body; F. Fourth working port of the first valve body;

[0063] J, the first working port of the second valve body; K, the second working port of the second valve body; G, the third working port of the second valve body; H, the fourth working port of the second valve body. Detailed Implementation

[0064] The technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit this disclosure or its application or use. All other embodiments obtained by those skilled in the art based on the embodiments of this disclosure without creative effort are within the scope of protection of this disclosure.

[0065] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of this disclosure. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following drawings denote similar items; therefore, once an item is defined in one drawing, it need not be further discussed in subsequent drawings.

[0066] In the description of this disclosure, it should be understood that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this disclosure.

[0067] In the description of this disclosure, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is generally based on the orientation or positional relationship shown in the accompanying drawings and is only for the convenience of describing this disclosure and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this disclosure; the directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0068] Embodiments of this disclosure provide a control valve, a hydraulic system, and a concrete pumping device.

[0069] The concrete pumping equipment provided in this disclosure includes a control valve or a hydraulic system as provided in this disclosure. This concrete pumping equipment has the corresponding advantages of either the control valve or the hydraulic system.

[0070] refer to Figures 1 to 10 The control valve provided in this embodiment includes a valve body 1 and a valve cover assembly 2.

[0071] The valve body 1 has a first port 11, a second port 12, a third port 13 and a fourth port 14 for connection to a hydraulic line.

[0072] The valve cover assembly 2 has a first oil passage 215 and a second oil passage 223 inside. The valve cover assembly 2 has a first working state and a second working state. The valve cover assembly 2 is movably installed on the valve body 1 so that the valve cover assembly 2 can switch between the first working state and the second working state.

[0073] In the first operating state, the first oil passage 215 connects the first oil port 11 and the third oil port 13, and the valve body 1 enters oil through one of the first oil port 11 and the third oil port 13 and exits oil through the other. The second oil passage 223 connects the second oil port 12 and the fourth oil port 14, and the valve body 1 enters oil through one of the second oil port 12 and the fourth oil port 14 and exits oil through the other. In the second operating state, the first oil passage 215 and / or the second oil passage 223 connect the third oil port 13 and the fourth oil port 14, and the valve body 1 enters oil through one of the third oil port 13 and the fourth oil port 14 and exits oil through the other. Alternatively, in the second operating state, the first oil passage 215 and / or the second oil passage 223 connect the first oil port 11 and the second oil port 12, and the valve body 1 enters oil through one of the first oil port 11 and the second oil port 12 and exits oil through the other.

[0074] The valve cover assembly 2 is movably mounted on the valve body 1. It can be rotatably or movablely mounted on the valve body 1, as long as it meets the requirements for switching working states. The valve cover assembly 2 can be a single valve cover or include multiple separate valve covers.

[0075] For the control valve provided in the embodiments of this disclosure, the first operating state and the second operating state are not used to limit the specific operating position of the valve cover assembly 2 relative to the valve body 1. The operating position of the valve cover assembly 2 can be more than the operating state of the valve cover assembly 2. In this disclosure, in the first operating state of the valve cover assembly 2, the first oil passage 215 and the second oil passage 223 are in a state in which the first oil port 11, the second oil port 12, the third oil port 13 and the fourth oil port 14 are connected in pairs; in the second operating state of the valve cover assembly 2, at least one of the first oil passage 215 and the second oil passage 223 is in a state in which two of the first oil port 11, the second oil port 12, the third oil port 13 and the fourth oil port 14 are connected, and the connection relationship is different from that in the first operating state.

[0076] The hydraulic system of a concrete pumping equipment typically includes two main pumping cylinders connected in series. In low-pressure operation, the rodless chambers of the two main pumping cylinders are connected, oil enters the rod chamber of one main pumping cylinder, and oil exits the rod chamber of the other main pumping cylinder. In high-pressure operation, the rod chambers of the two main pumping cylinders are connected, oil enters the rodless chamber of one main pumping cylinder, and oil exits the rodless chamber of the other main pumping cylinder.

[0077] In the description of this disclosure, high-low pressure switching refers to the switching of the hydraulic system of the concrete pumping equipment between the aforementioned high-pressure operating state and low-pressure operating state.

[0078] Typically, concrete pumping equipment can switch between high and low pressure by manually disassembling and assembling pipelines, but the disassembly and assembly process is particularly complex and labor-intensive; alternatively, it can rely on hydraulic or electrical control systems to achieve fully automatic high and low pressure switching, but the system is more complex and costly.

[0079] In the first operating state of the valve cover, two hydraulic oil passages can be formed inside the control valve, which can serve as the supply and return oil passages for the main pump cylinder, respectively. In the second operating state of the valve cover, a single hydraulic oil passage can be formed inside the control valve, which can be used to connect the rod-side or rodless-side chambers of the two main pump cylinders. Furthermore, the connection relationships of the first, second, third, and fourth oil ports differ between the two operating states. Therefore, by changing the operating state of the valve cover, each control valve can switch the hydraulic system between a state where oil is supplied to the rod-side (or rodless-side) chamber of one of the two main pump cylinders and oil is discharged from the rod-side (or rodless-side) chamber of the other, and a state where the rod-side (or rodless-side) chambers of the two main pump cylinders are interconnected, thereby facilitating high-low pressure switching. Based on the control valve provided in the embodiments of this disclosure, operators do not need to manually disassemble and reassemble pipelines, saving the workload of high-low pressure switching; it can also reduce the number of electrical control components, lower the complexity of the control system, and reduce manufacturing and operating costs.

[0080] While rotary valves can be used to switch between high and low pressure in related technologies, they are typically installed only on either the rod end or the rodless end of the main pump cylinder. Because the stroke of the main pump cylinder is relatively long, generally exceeding 1500mm, for example, if the rotary valve is installed on the rodless end, hydraulic oil from the main valve of the hydraulic system must first pass through a pipeline to the rotary valve before entering the rod end of the main cylinder. This results in a particularly long oil path and significant pressure loss during low-pressure operation, leading to poor fuel economy and high operating costs.

[0081] Based on the structure of the control valve provided in the embodiments of this disclosure, the hydraulic system of the concrete pumping equipment can employ multiple control valves to improve the above-mentioned problems.

[0082] For example, a hydraulic system can use two control valves, which are respectively located at the rod end and the rodless end of the pumping main cylinder.

[0083] refer to Figure 11 The hydraulic system provided in this embodiment includes a first cylinder 61, a second cylinder 62, a first control valve, and a second control valve.

[0084] The second hydraulic cylinder 62 is arranged side by side with the first hydraulic cylinder 61.

[0085] The first control valve is the control valve provided in the embodiments of this disclosure. The first control valve is disposed on one side of the rod chamber of the first cylinder 61 and the second cylinder 62. In the second working state of the valve cover assembly 2, the first oil passage 215 and / or the second oil passage 223 of the first control valve connect the third oil port 13 and the fourth oil port 14.

[0086] The second control valve is the control valve provided in the embodiments of this disclosure. The second control valve is disposed on one side of the rodless chamber of the first cylinder 61 and the second cylinder 62. In the second working state of the valve cover assembly 2, the first oil passage 215 and / or the second oil passage 223 of the second control valve connect the first oil port 11 and the second oil port 12.

[0087] In this configuration, the first port 11 of the first control valve is connected to the third port 13 of the second control valve, the second port 12 of the first control valve is connected to the fourth port 14 of the second control valve, the third port 13 of the first control valve is connected to the rod chamber of the first cylinder 61, the fourth port 14 of the first control valve is connected to the rod chamber of the second cylinder 62, the first port 11 of the second control valve is connected to the rodless chamber of the first cylinder 61, and the second port 12 of the second control valve is connected to the rodless chamber of the second cylinder 62. One of the first port 11 and the second port 12 of the first control valve is an oil inlet and the other is an oil outlet.

[0088] Figure 11 In the illustrated embodiment, the rod-side chambers and rodless chambers of the first cylinder 61 and the second cylinder 62, which are arranged side by side, are located on the same side. The first cylinder 61 and the second cylinder 62 can be used as the main pumping cylinders of a concrete pumping equipment.

[0089] The hydraulic system provided in the embodiments of this disclosure has a first control valve and a second control valve arranged at both ends of the first cylinder and the second cylinder, respectively. The first control valve can switch the hydraulic system between a state in which oil is supplied to the rod chamber of one of the two pumping main cylinders and oil is discharged from the rod chamber of the other, and a state in which the rod chambers of the two pumping main cylinders are interconnected. The second control valve can switch the hydraulic system between a state in which oil is supplied to the rodless chamber of one of the two pumping main cylinders and oil is discharged from the rodless chamber of the other, and a state in which the rodless chambers of the two pumping main cylinders are interconnected, thereby realizing high and low pressure switching.

[0090] Hydraulic oil from the main valve of the hydraulic system can directly enter the rod chamber of one of the first cylinders 61 and 62 through the first control valve. The rodless chamber of the first cylinder 61 and 62 can be directly connected through the second control valve. Hydraulic oil discharged from the other rod chamber of the first cylinder 61 and 62 can directly enter the main valve through the first control valve. In other words, if hydraulic oil needs to enter or exit the rod chamber of a cylinder, it does not need to bypass the rodless chamber. Similarly, if hydraulic oil needs to enter or exit the rodless chamber of a cylinder, it also does not need to bypass the rod chamber.

[0091] Therefore, the control valve and hydraulic system including the control valve provided in this embodiment can reduce the detours of hydraulic lines and decrease the complexity of hydraulic lines. Furthermore, the length of the inlet and return oil lines can each be reduced by at least approximately the length of one cylinder stroke. Considering the relatively long stroke of the main pumping cylinder, this significantly reduces the pressure loss of the hydraulic oil along the flow path, thereby reducing fuel consumption of the concrete pumping equipment. Thus, the manufacturing and operating costs of the concrete pumping equipment can be further reduced.

[0092] In some embodiments of the hydraulic system, the hydraulic system has a low-pressure operating state and a high-pressure operating state. In the low-pressure operating state, the valve cover assembly 2 of the first control valve is in a first operating state and the valve cover assembly 2 of the second control valve is in a second operating state. In the high-pressure operating state, the valve cover assembly 2 of the first control valve is in the second operating state and the valve cover assembly 2 of the second control valve is in the first operating state.

[0093] The meanings of low-voltage and high-voltage operating states can be found in the preceding descriptions. Figure 11 The diagram illustrates the operating status and specific working positions of the valve cover assemblies of the two control valves when the hydraulic system is in low-pressure and high-pressure operating states, respectively. (Combined with...) Figure 11 As can be seen, in the low-pressure working state, the valve cover assembly of the first control valve connects the first oil port 11 and the third oil port 13 of the first control valve and connects the second oil port 12 and the fourth oil port 14 of the first control valve. The valve cover assembly of the second control valve connects the first oil port 11 and the second oil port 12 of the second control valve. Oil enters the rod chamber of one of the first cylinders 61 and the second cylinder 62, and oil exits from the rod chamber of the other cylinder. The rodless chamber of the first cylinder 61 is connected to the rodless chamber of the second cylinder 62. In the high-pressure working state, the valve cover assembly of the first control valve connects the third oil port 13 and the fourth oil port 14 of the first control valve. The valve cover assembly of the second control valve connects the first oil port 11 and the third oil port 13 of the second control valve and connects the second oil port 12 and the fourth oil port 14 of the second control valve. Oil enters the rodless chamber of one of the first cylinders 61 and the second cylinder 62, and oil exits from the rodless chamber of the other cylinder. The rod chamber of the first cylinder 61 is connected to the rod chamber of the second cylinder 62.

[0094] In some embodiments of the control valve, such as Figure 5 and Figure 6 As shown, the valve cover assembly 2 includes a first valve cover 21 and a second valve cover 22. A first oil passage 215 is disposed within the first valve cover 21, and the first valve cover 21 is rotatably mounted on the valve body 1 so that the first oil passage 215 can selectively communicate with different oil ports of the valve body 1. A second oil passage 223 is disposed within the second valve cover 22, and the second valve cover 22 is rotatably mounted on the valve body 1 so that the second oil passage 223 can selectively communicate with different oil ports of the valve body 1.

[0095] The first valve cover 21 and the second valve cover 22 are separately provided and can rotate relative to the valve body 1 respectively. By rotating the first valve cover 21, the connection relationship between the first oil passage 215 and different oil ports of the valve body 1 can be changed. By rotating the second valve cover 22, the connection relationship between the second oil passage 223 and different oil ports of the valve body 1 can be changed. The structure of the oil port and oil passage on each valve cover can be designed to be simpler, easier to process, and can reduce the pressure loss of hydraulic oil inside the control valve.

[0096] In some embodiments of the control valve, such as Figure 1 , Figure 2 , Figure 7 and Figure 8 As shown, the first valve cover 21 and the second valve cover 22 are stacked on the valve body 1 in sequence.

[0097] In the above embodiments, the first valve cover 21 and the second valve cover 22 are installed on the same side of the valve body 1, thus freeing up more installation space on the valve body 1, facilitating the installation of the control valve onto the main valve of the hydraulic system or other locations on the concrete pumping equipment. For example, Figure 7 In the embodiment shown, the first oil port 11, the second oil port 12, the third oil port 13 and the fourth oil port 14 are opened on the first surface of the valve body 1, the first valve cover 21 is installed on the first surface of the valve body 1, the second valve cover 22 is installed on the first valve cover 21, and the valve body 1 is installed on the main valve 3 of the hydraulic system through the second surface located on the opposite side of the first surface.

[0098] Regarding the first control valve and the second control valve mentioned above, considering that they are installed in different positions, the valve body 1 of the first control valve and the second control valve can have the same or different shapes.

[0099] For example, Figures 1 to 7In the illustrated embodiment, valve body 1 is a first valve body 1A, which is provided with a first oil port 11, a second oil port 12, a third oil port 13, a fourth oil port 14, a first working port C, a second working port D, a third working port E, and a fourth working port F. The first oil port 11 communicates with the first working port C, the second oil port 12 communicates with the second working port D, the third oil port 13 communicates with the third working port E, and the fourth oil port 14 communicates with the fourth working port F. The first working port C and the third working port E of the first valve body 1A are located on the third surface adjacent to each other on the first surface, and the second working port D and the fourth working port F of the first valve body 1A are located on the fourth surface opposite to each other on the third surface.

[0100] For example, Figures 8 to 10 In the illustrated embodiment, valve body 1 is a second valve body 1B. The second valve body 1B is provided with a first oil port 11, a second oil port 12, a third oil port 13, a fourth oil port 14, a first working port J, a second working port K, a third working port G, and a fourth working port H. Specifically, the first oil port 11 communicates with the first working port J, the second oil port 12 communicates with the second working port K, the third oil port 13 communicates with the third working port G, and the fourth oil port 14 communicates with the fourth working port H. The first working port J and the second working port K of the first valve body 1A are located on a second surface opposite to the first surface, and the third working port G and the fourth working port H of the first valve body 1A are located on a third surface adjacent to the first surface.

[0101] In some embodiments of the control valve, such as Figure 5 , Figure 6 and Figure 11As shown, the first valve cover 21 has a fifth oil port 211, a sixth oil port 212, a seventh oil port 213, and an eighth oil port 214, with the fifth oil port 211 and the seventh oil port 213 connected through a first oil passage 215; the second valve cover 22 has a ninth oil port 221 and a tenth oil port 222, with the ninth oil port 221 and the tenth oil port 222 connected through a second oil passage 223; in the first operating state, the fifth oil port 211 is connected to the first oil port 11, the sixth oil port 212 is connected to the second oil port 12 and the ninth oil port 221, the seventh oil port 213 is connected to the third oil port 13, and the eighth oil port 214 is connected to the fourth oil port 14 and the tenth oil port 222; in the second operating state, the fifth oil port 211... 11 is connected to the third oil port 13, the seventh oil port 213 is connected to the fourth oil port 14, the sixth oil port 212 and the eighth oil port 214 are closed by the second valve cover 22, the first oil passage 215 connects the third oil port 13 and the fourth oil port 14, and the valve body 1 enters oil through one of the third oil port 13 and the fourth oil port 14 and exits oil through the other. Or, in the second working state, the fifth oil port 211 is connected to the second oil port 12, the seventh oil port 213 is connected to the first oil port 11, the sixth oil port 212 and the eighth oil port 214 are closed by the second valve cover 22, the first oil passage 215 connects the first oil port 11 and the second oil port 12, and the valve body 1 enters oil through one of the first oil port 11 and the second oil port 12 and exits oil through the other.

[0102] In some embodiments of the control valve, the sixth port 212 and the eighth port 214 penetrate the first valve cover 21 along the stacking direction of the first valve cover 21 and the second valve cover 22.

[0103] By providing a sixth oil port 212 and an eighth oil port 214 that penetrate the first valve cover 21, the second oil passage 223 can be connected to the oil port on the valve body 1 through the sixth oil port 212 and the eighth oil port 214.

[0104] In some embodiments of the control valve, the first oil port 11, the second oil port 12, the fourth oil port 14 and the third oil port 13 are rotationally symmetrically distributed; the fifth oil port 211, the sixth oil port 212, the eighth oil port 214 and the seventh oil port 213 are rotationally symmetrically distributed.

[0105] In the above embodiments, the first oil port 11, the second oil port 12, the third oil port 13, and the fourth oil port 14 are arranged in a square, as are the fifth oil port 211, the sixth oil port 212, the seventh oil port 213, and the eighth oil port 214. Therefore, the first valve cover 21 only needs to be rotated 90° to move from one working position to another, and in each working position, each oil port on the first valve cover 21 can be connected to each oil port on the valve body 1.

[0106] In some embodiments of the control valve, the cross section of the first valve cover 21 perpendicular to the stacking direction of the first valve cover 21 and the second valve cover 22 is square, and the fifth oil port 211 and the seventh oil port 213 are arranged adjacent to each other along one side of the square.

[0107] In some embodiments of the control valve, the cross section of the second valve cover 22 perpendicular to the stacking direction of the first valve cover 21 and the second valve cover 22 is square, and the ninth oil port 221 and the tenth oil port 222 are arranged adjacent to each other along one side of the square.

[0108] The fifth oil port 211 and the seventh oil port 213, which are arranged adjacent to each other along one side of the square, can make the length of the first oil passage 215 as short as possible. The ninth oil port 221 and the tenth oil port 222, which are arranged adjacent to each other along one side of the square, can make the length of the second oil passage 223 as short as possible, which helps to reduce the pressure loss of hydraulic oil in the control valve.

[0109] In some embodiments of the control valve, the control valve further includes a first connector 41 and a second connector 42, which pass through the second valve cover 22 and the first valve cover 21 in sequence and are connected to the valve body 1. The axis of the first connector 41 coincides with the rotation axis of the first valve cover 21 and the second valve cover 22, and the second connector 42 is distributed around the first connector 41.

[0110] like Figure 5 and Figure 6 As shown, the valve body 1 can be provided with a first mounting hole 15 for connecting with the first connecting member 41 and a second mounting hole 16 for connecting with the second connecting member 42. The first valve cover 21 can be provided with a third mounting hole 216 for the second connecting member 42 to pass through and a fourth mounting hole 217 for the first connecting member 41 to pass through. The second valve cover 22 can be provided with a fifth mounting hole 224 for the second connecting member 42 to pass through and a sixth mounting hole 225 for the first connecting member 41 to pass through. For the valve cover with a square cross-section, the third mounting hole 216 can be arranged at the four corners of the first valve cover 21, and the fifth mounting hole 224 can be arranged at the four corners of the second valve cover 22. Correspondingly, there can be four second connecting members 42.

[0111] The first connector 41 and the second connector 42 can be threaded connectors, such as bolts. When it is necessary to switch the working state of the valve cover, first remove the second connector 42, then loosen the first connector 41, and then rotate the first valve cover 21 or the second valve cover 22. This method can conveniently and quickly switch the working state of the valve cover assembly 2.

[0112] The first connector 41 can also serve only as a connection to the valve body 1, the first valve cover 21, and the second valve cover 22 without fixing them. It is only necessary to ensure that the first valve cover 21 and the second valve cover 22 can rotate around the axis of the first connector 41 after the second connector 42 is removed. For example, the first connector 41 can also be a pin.

[0113] In some embodiments of the control valve, the valve cover assembly 2 further includes a first handle 23 and / or a second handle 24. The first handle 23 is disposed on the first valve cover 21 and configured to rotate the first valve cover 21. The second handle 24 is disposed on the second valve cover 22 and configured to rotate the second valve cover 22.

[0114] The above-described configuration of the first handle 23 and the second handle 24 facilitates the operator's rotation of the valve cover. (Reference) Figure 11 It can be seen that the positions of the first handle 23 and the second handle 24 relative to the valve body 1 can also indicate the working state of the valve cover assembly 2, thereby facilitating the operator to quickly switch the working state of the valve cover assembly 2.

[0115] The following is combined Figures 1 to 11 The working process of the hydraulic system in the embodiments of this disclosure will be further explained.

[0116] The hydraulic system includes a main valve 3, a first cylinder 61, a second cylinder 62, a first control valve, and a second control valve. The second cylinder 62 is arranged side by side with the first cylinder 61. The first control valve is located on the rod-side of the first cylinder 61 and the second cylinder 62, and the second control valve is located on the rodless side of the first cylinder 61 and the second cylinder 62. Both the first and second control valves include a valve body 1 and a valve cover assembly 2 mounted on the valve body 1, wherein the first valve cover 21 and the second valve cover 22 are stacked sequentially on the valve body 1.

[0117] The valve body 1 of the first control valve is the first valve body 1A. The first valve body 1A is provided with a first oil port 11, a second oil port 12, a third oil port 13, a fourth oil port 14, a first working port C, a second working port D, a third working port E, and a fourth working port F. The first oil port 11 is connected to the first working port C, the second oil port 12 is connected to the second working port D, the third oil port 13 is connected to the third working port E, and the fourth oil port 14 is connected to the fourth working port F.

[0118] The valve body 1 of the second control valve is the second valve body 1B. The second valve body 1B is provided with a first oil port 11, a second oil port 12, a third oil port 13, a fourth oil port 14, a first working port J, a second working port K, a third working port G, and a fourth working port H. The first oil port 11 is connected to the first working port J, the second oil port 12 is connected to the second working port K, the third oil port 13 is connected to the third working port G, and the fourth oil port 14 is connected to the fourth working port H.

[0119] The first working port C of the first control valve is connected to the third working port G of the second control valve via the second pipeline 52. The second working port D of the first control valve is connected to the fourth working port H of the second control valve via the fourth pipeline 54. The third working port E of the first control valve is connected to the rod chamber of the first cylinder 61 via the first pipeline 51. The fourth working port F of the first control valve is connected to the rod chamber of the second cylinder 62 via the third pipeline 53. The first working port J of the second control valve is connected to the rodless chamber of the first cylinder 61, and the second working port K of the second control valve is connected to the rodless chamber of the second cylinder 62.

[0120] The main valve 3 has an inlet port P, an outlet port T, a first working port A, and a second working port B. The first port 11 of the first control valve is connected to the second working port B of the main valve 3. The main valve 3 is a directional control valve, comprising a first valve core 31 and a second valve core 32. The main valve 3 is equipped with a first control terminal XP and a second control terminal XR, allowing the first valve core 31 to be switched to different working positions. The main valve 3 is also equipped with a third control terminal XA and a fourth control terminal XB, allowing the second valve core 32 to be switched to different working positions. By changing the working positions of the first valve core 31 and the second valve core 32, the main valve 3 can make one of its first working ports A and B the inlet port and the other the outlet port. The valve body 1 of the first control valve is mounted on the main valve 3.

[0121] The first valve cover 21 has a fifth oil port 211, a sixth oil port 212, a seventh oil port 213 and an eighth oil port 214. The fifth oil port 211 and the seventh oil port 213 are connected through a first oil passage 215. The sixth oil port 212 and the eighth oil port 214 penetrate the first valve cover 21 along the stacking direction of the first valve cover 21 and the second valve cover 22. The second valve cover 22 has a ninth oil port 221 and a tenth oil port 222. The ninth oil port 221 and the tenth oil port 222 are connected through a second oil passage 223.

[0122] The valve body 1 is provided with a first mounting hole 15, the first valve cover 21 is provided with a third mounting hole 216, the first valve cover 21 can rotate around the axis of the third mounting hole 216, the second valve cover 22 is provided with a fifth mounting hole 224, the second valve cover 22 can rotate around the axis of the fifth mounting hole 224, and the first mounting hole 15, the third mounting hole 216 and the fifth mounting hole 224 are coaxial.

[0123] The valve cover assembly 2 has a first working state and a second working state.

[0124] For the first control valve, in the first operating state, the fifth port 211 is connected to the first port 11, the sixth port 212 is connected to the second port 12 and the ninth port 221, the seventh port 213 is connected to the third port 13, and the eighth port 214 is connected to the fourth port 14 and the tenth port 222; in the second operating state, the fifth port 211 is connected to the third port 13, the seventh port 213 is connected to the fourth port 14, and the sixth port 212 and the eighth port 214 are closed by the second valve cover 22.

[0125] For the second control valve, in the first operating state, the fifth port 211 is connected to the first port 11, the sixth port 212 is connected to the second port 12 and the ninth port 221, the seventh port 213 is connected to the third port 13, and the eighth port 214 is connected to the fourth port 14 and the tenth port 222; in the second operating state, the fifth port 211 is connected to the second port 12, the seventh port 213 is connected to the first port 11, and the sixth port 212 and the eighth port 214 are closed by the second valve cover 22.

[0126] In the low-pressure operating state of the hydraulic system, the first valve cover 21 and the second valve cover 22 of the first control valve are rotated to put it into the first operating state, and the first valve cover 21 and the second valve cover 22 of the second control valve are rotated to put it into the second operating state. If oil enters through the first working port A of the main valve 3 and oil exits through the second working port B of the main valve 3, the hydraulic oil enters the first control valve through the first working port A of the main valve 3, passes through the second oil port 12, the sixth oil port 212, the ninth oil port 221, the second oil passage 223, the tenth oil port 222, the eighth oil port 214, the fourth oil port 14, the fourth working port F of the first control valve, and the third pipeline 53, and enters the rod chamber of the second cylinder 62. The piston of the second cylinder 62 moves toward the rodless chamber end, and the hydraulic oil in the rodless chamber of the second cylinder 62 passes through the second working port K of the second control valve, the second oil port 12, the fifth oil port 211, the first oil passage 215, the seventh oil port 212, the second working port 2 ... 13. The first oil port 11 and the first working port J of the second control valve enter the rodless chamber of the first cylinder 61. The piston of the first cylinder 61 moves toward the rod chamber end. The hydraulic oil in the rod chamber of the first cylinder 61 passes through the first pipeline 51, the third working port E, the seventh oil port 213, the first oil passage 215, the fifth oil port 211 and the first oil port 11, and is discharged from the second working port B of the main valve 3. If oil enters through the second working port B of the main valve 3 and oil exits through the first working port A of the main valve 3, the flow path of the hydraulic oil in the hydraulic system is the opposite of the state where oil enters through the first working port A of the main valve 3 and oil exits through the second working port B of the main valve 3. This will not be elaborated here.

[0127] In the high-pressure working state of the hydraulic system, the first valve cover 21 and the second valve cover 22 of the first control valve are rotated to put it into the second working state, and the first valve cover 21 and the second valve cover 22 of the second control valve are rotated to put it into the first working state. If oil enters through the first working port A of the main valve 3 and exits through the second working port B of the main valve 3, the hydraulic oil enters the first control valve through the first working port A of the main valve 3, passes through the second oil port 12, the second working port D of the first control valve and the fourth pipeline 54 to enter the second control valve, and then passes through the fourth working port H, the fourth oil port 14, the eighth oil port 214, the tenth oil port 222, the second oil passage 223, the ninth oil port 221, the sixth oil port 212, the second oil port 12, and the second working port K of the second control valve to enter the rodless chamber of the second cylinder 62. The piston of the second cylinder 62 moves towards the rod end, and the hydraulic oil in the rod chamber of the second cylinder 62 passes through the third pipeline 53, the fourth working port F, the fourth oil port 14, the seventh oil port 213, the first oil passage 215, and the fifth oil port 211 of the first control valve. The third oil port 13, the third working port E of the first control valve, and the first pipeline 51 enter the rod chamber of the first cylinder 61. The piston of the first cylinder 61 moves toward the rodless chamber. The hydraulic oil in the rodless chamber of the first cylinder 61 passes through the first oil port 11, the fifth oil port 211, the first oil passage 215, the seventh oil port 213, the third oil port 13, the third working port G of the second control valve, and the second pipeline 52 into the first control valve. Then, it passes through the first working port C and the first oil port 11 of the first control valve and is discharged from the second working port B of the main valve 3. If oil enters through the second working port B of the main valve 3 and exits through the first working port A of the main valve 3, the flow path of the hydraulic oil in the hydraulic system is the opposite of the state where oil enters through the first working port A of the main valve 3 and oil exits through the second working port B of the main valve 3. This will not be elaborated here.

[0128] As can be seen from the working process of the hydraulic system described above, the first control valve is located at the rod end of the two cylinders, enabling it to connect one rod end of the cylinder to the inlet pipe and the other rod end to the outlet pipe, as well as to control the interconnection of the rod ends of the two cylinders. The second control valve is located at the rodless end of the two cylinders, enabling it to connect one rodless end of the cylinder to the inlet pipe and the other rodless end to the outlet pipe, as well as to control the interconnection of the rodless ends of the two cylinders. Regardless of whether the hydraulic system is operating at low or high pressure, this reduces unnecessary detours in the hydraulic lines, facilitating a shorter hydraulic line length, reducing pressure loss along the hydraulic oil's path, and decreasing fuel consumption in the concrete pumping equipment.

[0129] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this disclosure and not to limit them; although this disclosure has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications can still be made to the specific implementation of this disclosure or equivalent substitutions can be made to some technical features, all of which should be covered within the scope of the technical solutions claimed in this disclosure.

Claims

1. A control valve, characterized in that, include: The valve body (1) has a first port (11), a second port (12), a third port (13), and a fourth port (14) for connection to a hydraulic line; and The valve cover assembly (2) has a first oil passage (215) and a second oil passage (223) inside. The valve cover assembly (2) has a first working state and a second working state. The valve cover assembly (2) is movably mounted on the valve body (1) so that the valve cover assembly (2) can switch between the first working state and the second working state. In the first working state, the first oil passage (215) connects the first oil port (11) and the third oil port (13), and the valve body (1) receives oil through one of the first oil port (11) and the third oil port (13) and receives oil through the other. The second oil passage (223) connects the second oil port (12) and the fourth oil port (14), and the valve body (1) receives oil through one of the second oil port (12) and the fourth oil port (14) and receives oil through the other. In the second working state, the first oil passage (215) connects the first oil port (11) and the third oil port (13) and receives oil through the other. 15) and / or the second oil passage (223) connect the third oil port (13) and the fourth oil port (14), and the valve body (1) enters oil through one of the third oil port (13) and the fourth oil port (14) and exits oil through the other. Or, in the second working state, the first oil passage (215) and / or the second oil passage (223) connect the first oil port (11) and the second oil port (12), and the valve body (1) enters oil through one of the first oil port (11) and the second oil port (12) and exits oil through the other.

2. The control valve according to claim 1, characterized in that, The valve cover assembly (2) includes: A first valve cover (21) is provided inside the first valve cover (21), and the first valve cover (21) is rotatably mounted on the valve body (1) so that the first oil passage (215) can be selectively connected to different oil ports of the valve body (1); and The second valve cover (22) is provided inside the second valve cover (22), and the second valve cover (22) is rotatably mounted on the valve body (1) so that the second oil passage (223) can be selectively connected to different oil ports of the valve body (1).

3. The control valve according to claim 2, characterized in that, The first valve cover (21) and the second valve cover (22) are stacked on the valve body (1) in sequence.

4. The control valve according to claim 3, characterized in that, The first valve cover (21) has a fifth oil port (211), a sixth oil port (212), a seventh oil port (213) and an eighth oil port (214), and the fifth oil port (211) and the seventh oil port (213) are connected through the first oil passage (215); The second valve cover (22) has a ninth oil port (221) and a tenth oil port (222), which are connected through the second oil passage (223); In the first working state, the fifth oil port (211) is connected to the first oil port (11), the sixth oil port (212) is connected to the second oil port (12) and the ninth oil port (221), the seventh oil port (213) is connected to the third oil port (13), and the eighth oil port (214) is connected to the fourth oil port (14) and the tenth oil port (222); In the second working state, the fifth oil port (211) is connected to the third oil port (13), the seventh oil port (213) is connected to the fourth oil port (14), the sixth oil port (212) and the eighth oil port (214) are closed by the second valve cover (22), the first oil passage (215) connects the third oil port (13) and the fourth oil port (14), and the valve body (1) receives oil through one of the third oil port (13) and the fourth oil port (14) and receives oil through the other, or In the second working state, the fifth oil port (211) is connected to the second oil port (12), the seventh oil port (213) is connected to the first oil port (11), the sixth oil port (212) and the eighth oil port (214) are closed by the second valve cover (22), the first oil passage (215) connects the first oil port (11) and the second oil port (12), and the valve body (1) enters oil through one of the first oil port (11) and the second oil port (12) and exits oil through the other.

5. The control valve according to claim 4, characterized in that, The sixth oil port (212) and the eighth oil port (214) penetrate the first valve cover (21) along the stacking direction of the first valve cover (21) and the second valve cover (22).

6. The control valve according to claim 4, characterized in that, The first oil port (11), the second oil port (12), the fourth oil port (14), and the third oil port (13) are rotationally symmetrically distributed; The fifth oil port (211), the sixth oil port (212), the eighth oil port (214), and the seventh oil port (213) are rotationally symmetrically distributed.

7. The control valve according to claim 6, characterized in that, The first valve cover (21) has a square cross-section perpendicular to the stacking direction of the first valve cover (21) and the second valve cover (22), and the fifth oil port (211) and the seventh oil port (213) are arranged adjacent to each other along one side of the square; and / or The cross section of the second valve cover (22) perpendicular to the stacking direction of the first valve cover (21) and the second valve cover (22) is a square, and the ninth oil port (221) and the tenth oil port (222) are arranged adjacent to each other along one side of the square.

8. The control valve according to any one of claims 2 to 7, characterized in that, It also includes a first connector (41) and a second connector (42), the first connector (41) and the second connector (42) passing through the second valve cover (22) and the first valve cover (21) in sequence and connected to the valve body (1), the axis of the first connector (41) coincides with the rotation axis of the first valve cover (21) and the second valve cover (22), and the second connector (42) is distributed around the first connector (41).

9. The control valve according to any one of claims 2 to 7, characterized in that, The valve cover assembly (2) also includes: A first handle (23), disposed on the first valve cover (21), is configured to rotate the first valve cover (21); and / or The second handle (24) is disposed on the second valve cover (22) and is configured to drive the second valve cover (22) to rotate.

10. A hydraulic system, characterized in that, include: First oil cylinder (61); The second hydraulic cylinder (62) is arranged side by side with the first hydraulic cylinder (61); The first control valve, which is a control valve according to any one of claims 1 to 9, is disposed on one side of the rod chamber of the first cylinder (61) and the second cylinder (62). In the second working state of the valve cover assembly (2), the first oil passage (215) and / or the second oil passage (223) of the first control valve connect the third oil port (13) and the fourth oil port (14). and The second control valve, which is a control valve according to any one of claims 1 to 9, is disposed on one side of the rodless chamber of the first cylinder (61) and the second cylinder (62). In the second working state of the valve cover assembly (2), the first oil passage (215) and / or the second oil passage (223) of the second control valve connect the first oil port (11) and the second oil port (12). Wherein, the first oil port (11) of the first control valve is connected to the third oil port (13) of the second control valve, the second oil port (12) of the first control valve is connected to the fourth oil port (14) of the second control valve, the third oil port (13) of the first control valve is connected to the rod chamber of the first cylinder (61), the fourth oil port (14) of the first control valve is connected to the rod chamber of the second cylinder (62), the first oil port (11) of the second control valve is connected to the rodless chamber of the first cylinder (61), the second oil port (12) of the second control valve is connected to the rodless chamber of the second cylinder (62), and one of the first oil port (11) and the second oil port (12) of the first control valve is an oil inlet and the other is an oil outlet.

11. The hydraulic system according to claim 10, characterized in that, The hydraulic system has a low-pressure operating state and a high-pressure operating state, wherein... In the low-pressure operating state, the valve cover assembly (2) of the first control valve is in the first operating state, and the valve cover assembly (2) of the second control valve is in the second operating state. In the high-pressure working state, the valve cover assembly (2) of the first control valve is in the second working state, and the valve cover assembly (2) of the second control valve is in the first working state.

12. A concrete pumping device, comprising a control valve according to any one of claims 1 to 9, or comprising a hydraulic system according to claim 10 or 11.

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