Variable amplitude control hydraulic module, variable amplitude hydraulic control system and operation machine

Abstract

The invention belongs to the technical field of operation machinery and provides a variable-amplitude control hydraulic module, a variable-amplitude hydraulic control system and an operation machine.The variable-amplitude control hydraulic module comprises a variable-amplitude oil cylinder, an energy accumulator and an oil supplementing oil way, and the energy accumulator is connected to a rodless cavity of the variable-amplitude oil cylinder through a buffering oil way; a first control valve used for controlling on-off is arranged on the buffering oil way, one end of the oil supplementing oil way is connected with the oil tank, the other end of the oil supplementing oil way is connected to a rod cavity of the variable-amplitude oil cylinder, and a second control valve used for controlling on-off is arranged on the oil supplementing oil way. By opening the first control valve and the second control valve, the variable-amplitude oil cylinder can have an anti-impact function.

Description

Technical Field

[0001] This application belongs to the field of operating machinery technology, specifically relating to a luffing control hydraulic module, a luffing hydraulic control system, and operating machinery. Background Technology

[0002] Many types of heavy machinery, such as cranes, excavators, and telescopic forklifts, rely on luffing cylinders to adjust the working radius and height of their booms. In addition to bearing conventional static and operational loads, luffing cylinders sometimes also withstand instantaneous impact loads from the external environment during operation.

[0003] Taking a telescopic forklift as an example, when it uses its forks to pick up goods and maintain a close-to-the-ground posture for transfer or leveling operations, the forks, which are close to the ground, may suddenly experience severe jolting due to uneven ground, the presence of gravel or hard protrusions. This instantaneous ground reaction force is transmitted through the boom to the hinge point of the luffing cylinder, causing its piston rod to experience a strong axial impact. Such impact loads are dynamic, high-frequency, and difficult to predict, posing a serious challenge to the structural reliability of the cylinder and its connecting components.

[0004] Application content In view of the above-mentioned defects or deficiencies, this application provides a tandem hydraulic cylinder system and its oil replenishment control method, as well as a working machine, which aims to solve the technical problem that existing variable amplitude cylinders lack anti-shock function.

[0005] To achieve the above objectives, this application provides a luffing control hydraulic module, which includes a luffing cylinder, an accumulator, and a replenishing oil circuit. The accumulator is connected to the rodless chamber of the luffing cylinder via a buffer oil circuit. A first control valve for controlling the on / off state is provided on the buffer oil circuit. One end of the replenishing oil circuit is connected to an oil tank, and the other end is connected to the rod chamber of the luffing cylinder. A second control valve for controlling the on / off state is provided on the replenishing oil circuit.

[0006] In this embodiment, the energy storage device includes a first energy storage device and a second energy storage device, wherein the maximum energy storage pressure of the first energy storage device is greater than the maximum energy storage pressure of the second energy storage device.

[0007] In this embodiment, the luffing control hydraulic module also includes a charging oil circuit. One end of the charging oil circuit is connected to the accumulator, and the other end is connected to the rodless chamber working oil circuit of the luffing cylinder. A one-way valve is provided on the charging oil circuit. The one-way valve is configured to open when the pressure oil in the rodless chamber working oil circuit flows to the accumulator through the charging oil circuit and to close in the reverse direction.

[0008] In this embodiment, the first control valve is an electromagnetic switch valve and has a first open valve position and a first shut-off valve position. The first shut-off valve position is the resident valve position of the first control valve, and the first open valve position is the reversing valve position of the first control valve.

[0009] In this embodiment, the first shut-off valve position is a one-way shut-off valve position, which is configured to open when hydraulic oil flows from the accumulator to the rodless chamber of the luffing cylinder and shut off in the reverse direction.

[0010] In this embodiment, the second control valve is an electromagnetic switch valve and has a second open valve position and a second shut-off valve position. The second shut-off valve position is the normal valve position of the first control valve, and the second open valve position is the reversing valve position of the second control valve.

[0011] In this embodiment, the second shut-off valve position is a one-way shut-off valve position. The second shut-off valve position is configured to allow hydraulic oil to flow from the oil tank through the replenishment oil circuit to the rod chamber of the luffing cylinder and to shut off in the reverse direction.

[0012] In this embodiment, a floating oil passage is provided between the rod chamber and the rodless chamber of the luffing cylinder, and a third control valve for controlling the on / off state is provided on the floating oil passage.

[0013] To achieve the above objectives, this application also provides a luffing hydraulic control system, wherein the luffing hydraulic control system includes a hydraulic pump, a luffing control main valve, and a luffing control hydraulic module as described above.

[0014] To achieve the above objectives, this application also provides a working machine that includes the variable-amplitude hydraulic control system described above.

[0015] Through the above technical solution, the variable amplitude control hydraulic module provided in this application embodiment has the following beneficial effects: By opening the first and second control valves, the luffing cylinder can be equipped with an anti-shock function. Specifically, when the boom of the working machinery is subjected to an impact, the hydraulic shock generated in the rodless chamber of the luffing cylinder will enter the accumulator through the buffer oil circuit, and the accumulator will absorb this portion of the impact energy. At the same time, the rod chamber of the luffing cylinder can simultaneously draw in an appropriate amount of oil through the replenishment oil circuit to avoid vacuum and cavitation. Under the synergistic mechanism of "one release and one replenishment", the luffing cylinder can effectively buffer external impact forces through micro-movement, thereby significantly improving the impact resistance, operational reliability and service life of the cylinder and the entire machine. When the external impact disappears, the accumulator will release the previously buffered energy, thereby driving the luffing cylinder to return to its previous working position.

[0016] Other features and advantages of this application will be described in detail in the following detailed description section. Attached Figure Description

[0017] The accompanying drawings are provided to illustrate the present application and form part of the specification. They are used together with the following detailed description to explain the present application, but do not constitute a limitation thereof. In the drawings: Figure 1This is a hydraulic schematic diagram of the variable amplitude control hydraulic module according to the embodiments of this application.

[0018] Explanation of reference numerals in the attached figures 1. Luffing cylinder; 1a. Rodless chamber working oil circuit; 1b. Rod chamber working oil circuit; 21. First accumulator; 22. Second accumulator; 31. First control valve; 32. Second control valve; 33. Third control valve; 34. Check valve; 35. One-way balance valve; 4a. Buffer oil circuit; 4b. Oil replenishment oil circuit; 4c. Pressurization oil circuit; 4d. Floating oil circuit. Detailed Implementation

[0019] The specific embodiments of this application will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the scope of this application.

[0020] The amplitude control hydraulic module of this application is described below with reference to the accompanying drawings.

[0021] This application provides a variable amplitude control hydraulic module, such as... Figure 1 As shown, the luffing control hydraulic module includes a luffing cylinder 1, an accumulator, and a replenishing oil circuit 4b.

[0022] A buffer oil passage 4a is provided between the accumulator and the rodless chamber of the luffing cylinder 1. The accumulator is directly or indirectly connected to the rodless chamber of the luffing cylinder 1 through the buffer oil passage 4a. A first control valve 31 for controlling the on and off is provided on the buffer oil passage 4a.

[0023] One end of the oil replenishment circuit 4b is connected to the oil tank, and the other end is connected to the rod chamber of the luffing cylinder 1. The oil replenishment circuit 4b is equipped with a second control valve 32 for controlling the on and off states.

[0024] By opening the first control valve 31 and the second control valve 32, the luffing cylinder 1 can be equipped with an anti-shock function. Specifically, when the boom of the working machine is subjected to an impact, the hydraulic shock generated in the rodless chamber of the luffing cylinder 1 will enter the accumulator through the buffer oil circuit 4a, and the accumulator will absorb this part of the impact energy. At the same time, the rod chamber of the luffing cylinder 1 can simultaneously draw in an appropriate amount of oil through the replenishment oil circuit 4b to avoid the generation of vacuum and cavitation. Under the coordinated mechanism of "one release and one replenishment", the luffing cylinder 1 can effectively buffer the external impact force through micro-movement, thereby significantly improving the impact resistance, working reliability and service life of the cylinder and the whole machine. When the external impact disappears, the accumulator will release the previously buffered energy, thereby driving the luffing cylinder 1 to return to the previous working position.

[0025] like Figure 1As shown, in this embodiment, the energy storage device includes a first energy storage device 21 and a second energy storage device 22. The maximum energy storage pressure of the first energy storage device 21 is greater than the maximum energy storage pressure of the second energy storage device 22. In other words, among the two energy storage devices, the first energy storage device 21 is a high-pressure energy storage device, and the second energy storage device 22 is a low-pressure energy storage device.

[0026] When the external impact force on the boom is small, the second accumulator 22 can absorb these low-energy impacts first and sensitively by means of low pre-charge pressure and fast dynamic response characteristics, so that the luffing operation is more smooth and stable when dealing with minor road bumps.

[0027] When the external impact force on the boom is large and exceeds the energy storage limit of the second accumulator 22, the first accumulator 21 will absorb this energy. Through the first accumulator 21, the upper limit of the impact resistance of the luffing cylinder 1 can be increased.

[0028] like Figure 1 As shown, in this embodiment, the luffing control hydraulic module also includes a charging oil circuit 4c. One end of the charging oil circuit 4c is connected to the accumulator, and the other end is connected to the rodless chamber working oil circuit 1a of the luffing cylinder 1. A one-way valve 34 is provided on the charging oil circuit 4c. The one-way valve 34 is configured to open when the pressure oil in the rodless chamber working oil circuit 1a flows to the accumulator through the charging oil circuit 4c and to close in the reverse direction.

[0029] When oil enters the rodless chamber of the luffing cylinder 1, pressurized oil also flows to the accumulator through the charging oil circuit 4c, thereby charging the accumulator. Since the charging oil circuit 4c is connected to the working oil circuit 1a of the rodless chamber, the pressure in the accumulator can be ensured to be equal to that in the rodless chamber of the luffing cylinder 1 before the first control valve 31 is opened. Thus, when the first control valve 31 is opened, the cylinder can be kept stationary in its current working position. The check valve 34 can isolate the accumulator from the working oil circuit 1a of the rodless chamber, preventing the hydraulic oil in the accumulator from flowing back to the working oil circuit 1a of the rodless chamber through the charging oil circuit 4c before the first control valve 31 is opened.

[0030] It is understandable that one end of the charging oil circuit 4c is connected to the accumulator. This could mean that the charging oil circuit 4c is directly connected to the first accumulator 21 and the second accumulator 22, or it could mean that the charging oil circuit 4c is connected to the accumulator through an intermediate oil circuit. The other end of the charging oil circuit 4c is connected to the rodless chamber working oil circuit 1a of the luffing cylinder 1. This means that the charging oil circuit 4c is directly or indirectly connected to the rodless chamber working oil circuit 1a of the luffing cylinder 1 through an intermediate oil circuit.

[0031] like Figure 1As shown, in this embodiment, the first control valve 31 can be a two-position, two-way solenoid valve. The two-position, two-way first control valve 31 may include a first open valve position and a first shut-off valve position. The first shut-off valve position is the normally occupied valve position of the first control valve 31, and the first open valve position is the reversing valve position of the first control valve 31. When the first control valve 31 needs to be opened, the solenoid of the first control valve 31 is energized, and the first reversing valve will switch to the first open valve position. When the first control valve 31 is not opened, the solenoid of the first control valve 31 is de-energized, and the first reversing valve will reset to the first shut-off valve position.

[0032] like Figure 1 As shown, in this embodiment, the first shut-off valve position can be a one-way shut-off valve position. The first shut-off valve position is configured to open when hydraulic oil flows from the accumulator to the rodless chamber of the luffing cylinder 1 and close in the reverse direction. By setting the first shut-off valve position to one-way shut-off, when oil leakage occurs in the rodless chamber of the luffing cylinder 1 and the first control valve 31 is not open, the accumulator can replenish an appropriate amount of hydraulic oil to the rodless chamber of the luffing cylinder 1.

[0033] like Figure 1 As shown, in this embodiment, the second control valve 32 can also be a two-position, two-way solenoid valve. The two-position, two-way second control valve 32 includes a second open valve position and a second shut-off valve position. The second shut-off valve position is the normal operating position of the first control valve 31, and the second open valve position is the reversing valve position of the second control valve 32. When the second control valve 32 needs to be opened, the solenoid of the second control valve 32 is energized, and the second reversing valve will switch to the second open valve position. When the second control valve 32 is not opened, the solenoid of the second control valve 32 is de-energized, and the second reversing valve will reset to the second shut-off valve position.

[0034] like Figure 1 As shown, in this embodiment, the second shut-off valve position can be a one-way shut-off valve position. The second shut-off valve position is configured to allow hydraulic oil to flow from the oil tank to the rod chamber of the luffing cylinder 1 through the replenishment oil circuit 4b, and to shut off in the reverse direction. By setting the second shut-off valve position to a one-way shut-off valve position, when the second control valve 32 is not open and there is oil leakage in the rod chamber of the luffing cylinder 1, oil replenishment to the rod chamber of the luffing cylinder 1 can be achieved through the replenishment oil circuit 4b.

[0035] In this embodiment, the first control valve 31 and the second directional valve may also be other types of directional valves with oil circuit on / off control.

[0036] In work machinery with a platform at the boom end (such as boom-type aerial work platforms, boom-type forklifts, etc.), a floating oil circuit 4d can be set between the rod-side and rodless sides of the luffing cylinder 1 in its luffing control hydraulic module, and a third control valve 33 for controlling the on / off state is provided on the floating oil circuit 4d. Through the cooperation of the third control valve 33 and the second control valve 32, dynamic leveling of the platform at the boom end can be achieved.

[0037] Specifically, such as Figure 1 As shown, when the platform machinery travels on a flat road, the leveling structure on the machinery locks the geometric relationship between the platform, boom, and luffing cylinder 1 through rigid motion constraints. At this time, the platform at the end of the boom is horizontal. When the working machinery travels on an uneven road surface, the frame may tilt forward or backward. At this time, by controlling the second and third reversing valves to open, the rodless chamber and the rod chamber of the luffing cylinder 1 can be connected, and the rod chamber of the luffing cylinder 1 can be connected to the oil tank. The luffing cylinder 1 can adaptively float and extend under the action of external force.

[0038] When the machine is facing downwards, by opening the second control valve 32 and the third control valve 33, the luffing cylinder 1 can float and retract under the action of external force. When the luffing cylinder 1 floats and retracts, part of the hydraulic oil in the rodless chamber flows to the rod chamber of the luffing cylinder 1 through the floating oil circuit 4d, and the excess flows to the oil tank through the floating oil circuit 4d and the replenishing oil circuit 4b. Under the constraint of the leveling mechanism, when the luffing cylinder 1 retracts to the point where the platform is level again, the luffing cylinder 1 will remain stationary in its current position, thus completing the adaptive leveling of the luffing cylinder 1.

[0039] When the working machinery is facing upwards, by controlling the opening of the second control valve 32 and the third control valve 33, the luffing cylinder 1 can float and extend under the action of external force. When the luffing cylinder 1 extends, the oil in the rod chamber will flow to the rodless chamber of the luffing cylinder 1 through the floating oil circuit 4d. At the same time, the oil tank can replenish oil to the rodless chamber of the luffing cylinder 1 through the replenishment oil circuit 4b and the floating oil circuit 4d. Under the constraint of the leveling mechanism, when the luffing cylinder 1 extends to the point where the platform is level again, the luffing cylinder 1 will remain stationary in the current position, thus completing the adaptive leveling of the luffing cylinder 1.

[0040] like Figure 1 As shown, in this embodiment, a one-way balance valve 35 is also provided on the rodless chamber working oil circuit 1a of the luffing cylinder 1. The reversing control end of the one-way balance valve 35 is connected to the rod chamber working oil circuit 1b of the luffing cylinder 1. By controlling the one-way bypass and reverse opening of the one-way balance valve 35, the stable locking of the luffing cylinder 1 at any position is ensured.

[0041] In this embodiment, the first control valve 31, the second control valve 32, the third control valve 33, and the one-way balance valve 35 can be integrated into one valve body.

[0042] To achieve the above objectives, this application also provides a luffing hydraulic control system, which includes a hydraulic pump, a luffing control main valve, and a luffing control hydraulic module as described above. Since the luffing hydraulic control system adopts all the technical solutions of the above embodiments, it at least possesses the beneficial effects brought by the above embodiments, and will not be repeated here.

[0043] In this embodiment, the luffing hydraulic control system also includes a controller, which is used to control the opening of the first control valve 31, the second control valve 32, and the third control valve 33, so that the system can perform the luffing cylinder anti-shock operation and the platform automatic leveling operation respectively.

[0044] To achieve the above objectives, this application also provides a working machine, which includes the luffing hydraulic control system described above. The working machine can be a crane, a telescopic boom aerial work platform, a telescopic boom forklift, or other machinery. Since the working machine also adopts all the technical solutions of the above embodiments, it at least possesses the beneficial effects brought by the above embodiments, and will not be repeated here.

[0045] In the description of this application, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0046] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between components; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0047] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0048] Although embodiments of this application have been described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A variable amplitude control hydraulic module, characterized by, The amplitude control hydraulic module comprises: an amplitude cylinder (1); an accumulator connected to a rodless chamber of the amplitude cylinder (1) through a buffer oil path (4a) provided with a first control valve (31) for controlling on-off; a makeup oil path (4b) having one end connected to an oil tank and the other end connected to a rod chamber of the amplitude cylinder (1), the makeup oil path (4b) being provided with a second control valve (32) for controlling on-off.

2. The variable amplitude control hydraulic module of claim 1, wherein, The accumulator comprises a first accumulator (21) and a second accumulator (22), the maximum accumulator pressure of the first accumulator (21) being greater than that of the second accumulator (22).

3. The variable amplitude control hydraulic module of claim 1, wherein, The amplitude control hydraulic module further comprises a pressure charging oil path (4c) having one end connected to the accumulator and the other end connected to a rodless chamber working oil path (1a) of the amplitude cylinder (1), the pressure charging oil path (4c) being provided with a one-way valve (34) configured to be turned on when pressure oil in the rodless chamber working oil path (1a) flows to the accumulator through the pressure charging oil path (4c) and turned off in the opposite direction.

4. The variable amplitude control hydraulic module of claim 1, wherein, The first control valve (31) is an electromagnetic switch valve provided with a first on valve position and a first off valve position, the first off valve position being a constant valve position of the first control valve (31), and the first on valve position being a reversing valve position of the first control valve (31).

5. The variable amplitude control hydraulic module of claim 4, wherein, The first off valve position is a one-way off valve position configured to be turned on when hydraulic oil flows from the accumulator to the rodless chamber of the amplitude cylinder (1) and turned off in the opposite direction.

6. The variable amplitude control hydraulic module of claim 1, wherein, The second control valve (32) is an electromagnetic switch valve provided with a second on valve position and a second off valve position, the second off valve position being a constant valve position of the first control valve (31), and the second on valve position being a reversing valve position of the second control valve (32).

7. The variable amplitude control hydraulic module of claim 6, wherein, The second off valve position is a one-way off valve position configured to be turned on when hydraulic oil flows from the oil tank to the rod chamber of the amplitude cylinder (1) through the makeup oil path (4b) and turned off in the opposite direction.

8. The amplitude control hydraulic module according to any one of claims 1 to 7, characterized in that The amplitude cylinder (1) is further provided with a floating oil path (4d) between the rod chamber and the rodless chamber, the floating oil path (4d) being provided with a third control valve (33) for controlling on-off.

9. A variable amplitude hydraulic control system characterized by, The amplitude hydraulic control system comprises a hydraulic pump, an amplitude control main valve, and the amplitude control hydraulic module according to any one of claims 1 to 8.

10. A work machine characterized by, The working machine comprises the amplitude hydraulic control system according to claim 9.

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