Telescopic floating type hydraulic system and hydraulic support

Abstract

The utility model relates to the technical field of hydraulic supports, in particular to a telescopic floating type hydraulic system and a hydraulic support. The telescopic floating type hydraulic system comprises an advancing jack, a telescopic jack and a floating two-way lock, and a rodless cavity of the advancing jack is connected with a first liquid inlet flow channel; a rod cavity of the pushing jack is connected with the first liquid return flow channel; the liquid outlet end of the floating two-way lock is connected with a rod cavity of the telescopic jack and a rodless cavity of the telescopic jack respectively; the liquid inlet end of the floating two-way lock is connected with the second liquid return flow channel and the second liquid inlet flow channel; and the control end of the floating bidirectional lock is connected with the first liquid inlet flow channel through the floating control flow channel. The advancing jack and the telescopic jack are linked through the floating bidirectional lock, so that floating control of the telescopic jack during frame moving is realized, and overpressure damage of the telescopic jack due to external force caused by improper operation is prevented; meanwhile, in the frame moving process, the total time for operating the telescopic jack to stretch out and retract is shortened, and the operation efficiency is improved.

Description

Technical Field

[0001] This application relates to the technical field of hydraulic supports, and particularly to a telescopic floating hydraulic system and a hydraulic support. Background Art

[0002] A hydraulic support is a structure used to control the mine pressure in a coal mining face. Its main function is to support and fix infrastructure such as mine shafts and mine roadways during the coal mining process to ensure safety and stability during the mining process. At the same time, the hydraulic support can also improve the mining efficiency, reduce potential accident hazards, and provide a safer and more stable working environment for operators.

[0003] A hydraulic support generally includes a pushing jack and a telescopic jack. The pushing jack is located in the middle of the base of the hydraulic support, and its main function is to push the hydraulic support; the telescopic jack is located on the top beam of the hydraulic support, and its main function is to control the extension and retraction of the telescopic beam.

[0004] Usually, the hydraulic system adopts a linkage scheme for the actions of the pushing jack and the telescopic jack. When the pushing jack extends, that is, when the support is moved, the telescopic jack needs to retract. However, due to improper operation, it may cause the telescopic jack to retract untimely and be damaged by overpressure under external force; moreover, every time the support is moved, the telescopic jack retracts completely, which will affect the operation efficiency. Summary of the Utility Model

[0005] This application aims to at least solve one of the technical problems in the prior art or related technologies, that is, due to improper operation, it may cause the telescopic jack to retract untimely and be damaged by overpressure under external force; moreover, every time the support is moved, the telescopic jack retracts completely, which will affect the operation efficiency.

[0006] To this end, this application provides a telescopic floating hydraulic system and a hydraulic support. The pushing jack and the telescopic jack are linked by a floating two-way lock to achieve floating control of the telescopic jack during support movement, preventing the telescopic jack from being damaged by overpressure under external force due to improper operation; at the same time, during the normal support movement process, the contraction distance of the telescopic jack can be relaxed, without complete contraction, reducing the total time of the operations of extending and retracting the telescopic jack, and improving the operation efficiency.

[0007] This application also provides a hydraulic support including the above-mentioned telescopic floating hydraulic system.

[0008] A telescopic floating hydraulic system according to an embodiment of the first aspect of the present application includes: a pushing jack, a telescopic jack, and a floating two-way lock. Among them, the pushing jack includes: a rodless chamber of the pushing jack and a rod chamber of the pushing jack. The rodless chamber of the pushing jack is connected to the first liquid inlet channel; the rod chamber of the pushing jack is connected to the first liquid return channel; the telescopic jack includes: a rodless chamber of the telescopic jack and a rod chamber of the telescopic jack. The first liquid outlet end of the floating two-way lock is connected to the rod chamber of the telescopic jack; the second liquid outlet end of the floating two-way lock is connected to the rodless chamber of the telescopic jack; the first liquid inlet end of the floating two-way lock is connected to the second liquid return channel; the second liquid inlet end of the floating two-way lock is connected to the second liquid inlet channel; the control end of the floating two-way lock is connected to the first liquid inlet channel through a floating control channel.

[0009] Optionally, the floating two-way lock includes: a first double-ended hydraulically controlled one-way valve and a second double-ended hydraulically controlled one-way valve. The liquid outlet end of the first double-ended hydraulically controlled one-way valve is connected to the rod chamber of the telescopic jack; the liquid outlet end of the second double-ended hydraulically controlled one-way valve is connected to the rodless chamber of the telescopic jack; the liquid inlet end of the first double-ended hydraulically controlled one-way valve is respectively connected to the second liquid return channel and the first control end of the second double-ended hydraulically controlled one-way valve; the liquid inlet end of the second double-ended hydraulically controlled one-way valve is respectively connected to the second liquid inlet channel and the first control end of the first double-ended hydraulically controlled one-way valve; the second control end of the first double-ended hydraulically controlled one-way valve and the second control end of the second double-ended hydraulically controlled one-way valve are respectively connected to the first liquid inlet channel through a floating control channel.

[0010] Optionally, the number of telescopic jacks is at least 2, and at least 2 telescopic jacks are connected in parallel.

[0011] Optionally, a stroke sensor is provided on the pushing jack, and an electromagnetic throttle valve is provided on the first liquid inlet channel; the stroke sensor is used to detect the extended length of the pushing jack, and when it reaches a predetermined position, it sends a control signal to the electromagnetic throttle valve; the electromagnetic throttle valve is used to reduce the flow rate of the first liquid inlet channel to a preset ratio when receiving the control signal.

[0012] Optionally, the predetermined position is 0.4 - 0.7 of the preset stroke of the pushing jack extending; the preset ratio is 0.3 - 0.8.

[0013] Optionally, the telescopic floating hydraulic system further includes a single-ended hydraulically controlled one-way valve. The liquid inlet end of the single-ended hydraulically controlled one-way valve is connected to the first liquid return channel, the liquid outlet end of the single-ended hydraulically controlled one-way valve is connected to the rod chamber of the pushing jack, and the control end of the single-ended hydraulically controlled one-way valve is connected to the first liquid inlet channel.

[0014] Optionally, a stop valve is provided on the floating control channel.

[0015] Optionally, a first safety valve is provided on the channel where the liquid outlet end of the floating two-way lock is connected to the rodless chamber of the telescopic jack.

[0016] Optionally, a second safety valve is provided on the flow channel where the liquid outlet end of the single-ended hydraulically controlled check valve is connected to the rod chamber of the jack for pushing.

[0017] A hydraulic support provided in the second aspect embodiment of the present application is provided with the above telescopic floating hydraulic system. Since the telescopic floating hydraulic system has the above technical effects, the hydraulic support provided with this telescopic floating hydraulic system should also have corresponding technical effects.

[0018] At least one of the technical solutions in the above technical solutions has the following advantages or beneficial effects:

[0019] For a telescopic floating hydraulic system and a hydraulic support provided in the embodiment of the present application, the telescopic floating hydraulic system includes: a jack for pushing, a telescopic jack, and a floating two-way lock. Among them, the jack for pushing includes: a rodless chamber of the jack for pushing and a rod chamber of the jack for pushing. The rodless chamber of the jack for pushing is connected to the first liquid inlet flow channel; the rod chamber of the jack for pushing is connected to the first liquid return flow channel; the telescopic jack includes: a rodless chamber of the telescopic jack and a rod chamber of the telescopic jack. The first liquid outlet end of the floating two-way lock is connected to the rod chamber of the telescopic jack; the second liquid outlet end of the floating two-way lock is connected to the rodless chamber of the telescopic jack; the first liquid inlet end of the floating two-way lock is connected to the second liquid return flow channel; the second liquid inlet end of the floating two-way lock is connected to the second liquid inlet flow channel; the control end of the floating two-way lock is connected to the first liquid inlet flow channel through a floating control flow channel. The jack for pushing and the telescopic jack are linked through the floating two-way lock to achieve floating control of the telescopic jack during the support moving operation, preventing overpressure damage of the telescopic jack due to external force caused by improper operation; at the same time, during the normal support moving process, the contraction distance of the telescopic jack can be relaxed, without complete contraction, reducing the total time of the operations of extending and retracting the telescopic jack, and improving the operation efficiency. Description of the Drawings

[0020] In order to more clearly illustrate the technical solutions of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, for those of ordinary skill in the art, other drawings can also be obtained based on these drawings without creative efforts.

[0021] Figure 1 Shows a schematic principle diagram of a telescopic floating hydraulic system provided in the embodiment of the present application;

[0022] Figure 2 Shows a schematic structural diagram of a hydraulic support provided in the embodiment of the present application.

[0023] Description of the Reference Numerals:

[0024] 1. Push jack, 101. Rodless cavity of the push jack, 102. Rod cavity of the push jack, 103. Stroke sensor, 2. Telescopic jack, 201. Rodless cavity of the telescopic jack, 202. Rod cavity of the telescopic jack, 3. Single-ended hydraulic check valve, 4. Floating two-way lock, 401. First double-ended hydraulic check valve, 402. Second double-ended hydraulic check valve, 5. Electromagnetic throttle valve, 6. Stop valve, 7. First safety valve, 8. Second safety valve, 9. First inlet fluid passage, 10. First return fluid passage, 11. Floating control passage, 12. Second inlet fluid passage, 13. Second return fluid passage. Detailed implementation manners

[0025] For better explaining the present application for easy understanding, the present application will be described in detail below in conjunction with the accompanying drawings through specific implementation manners.

[0026] As described above, a hydraulic support is a support structure arranged in a mine roadway and controlled and operated through a hydraulic system. It utilizes the hydraulic principle and provides power through a hydraulic pump station to make the top beam of the support closely contact the roadway roof, thereby realizing the support and protection of the roadway. During the coal mining process, as the working face advances, the roof of the mine roadway may be affected by mine pressure and sink or collapse. At this time, the hydraulic support can play its role of support and protection to ensure the stability and safety of the roadway.

[0027] The hydraulic support generally includes: a push jack and a telescopic jack. As Figure 2 shown, the push jack is located in the middle of the base of the hydraulic support. Its main function is to push the hydraulic support. During coal mining operations, the hydraulic support needs to continuously adjust its position as the shearer moves to ensure the stability and safety of the working face. Precise control is carried out through the push jack to achieve the smooth pulling and moving of the hydraulic support. The telescopic jack is located on the top beam of the hydraulic support, and its main function is to control the extension and retraction of the telescopic beam. During the coal mining process, as the coal seam is mined, the roof will be continuously exposed, and timely support is required to prevent safety accidents such as roof falls. The telescopic jack can precisely control the extension length and angle of the telescopic beam through its telescopic function to adapt to roofs of different heights and inclinations and ensure the support effect.

[0028] Usually, the hydraulic system adopts a linkage scheme for the actions of the push jack and the telescopic jack. When the push jack extends, that is, when the support is moved, the telescopic jack needs to retract. However, due to improper operation, it may cause the telescopic jack to retract untimely and be damaged due to overpressure by external forces; moreover, every time the support is moved, the telescopic jack retracts completely, which will affect the operation efficiency.

[0029] To at least solve one of the technical problems existing in the prior art or related technologies, the present application provides a telescopic floating hydraulic system and a hydraulic support. The telescopic floating hydraulic system includes: a push jack, a telescopic jack, and a floating two-way lock. Among them, the push jack includes: a rodless chamber of the push jack and a rod chamber of the push jack. The rodless chamber of the push jack is connected to the first liquid inlet channel; the rod chamber of the push jack is connected to the first liquid return channel; the telescopic jack includes: a rodless chamber of the telescopic jack and a rod chamber of the telescopic jack. The first liquid outlet end of the floating two-way lock is connected to the rod chamber of the telescopic jack; the second liquid outlet end of the floating two-way lock is connected to the rodless chamber of the telescopic jack; the first liquid inlet end of the floating two-way lock is connected to the second liquid return channel; the second liquid inlet end of the floating two-way lock is connected to the second liquid inlet channel; the control end of the floating two-way lock is connected to the first liquid inlet channel through a floating control channel. The push jack and the telescopic jack are linked through the floating two-way lock to realize the floating control of the telescopic jack during the support moving process, preventing the telescopic jack from being damaged due to overpressure caused by external forces due to improper operation; at the same time, during the normal support moving process, the retraction distance of the telescopic jack can be relaxed without complete retraction, reducing the total time of the extending and retracting actions of the telescopic jack and improving the operation efficiency.

[0030] The following describes a telescopic floating hydraulic system according to some embodiments provided by the present application with reference to the accompanying drawings.

[0031] See Figures 1 to 2 As shown in, a telescopic floating hydraulic system according to an embodiment of the first aspect of the present application includes: a push jack 1, a telescopic jack 2, and a floating two-way lock 4. Among them, the push jack 1 includes: a rodless chamber 101 of the push jack and a rod chamber 102 of the push jack. The rodless chamber 101 of the push jack is connected to the first liquid inlet channel 9; the rod chamber 102 of the push jack is connected to the first liquid return channel 10; the telescopic jack 2 includes: a rodless chamber 201 of the telescopic jack and a rod chamber 202 of the telescopic jack. The first liquid outlet end of the floating two-way lock 4 is connected to the rod chamber 202 of the telescopic jack; the second liquid outlet end of the floating two-way lock 4 is connected to the rodless chamber 201 of the telescopic jack; the first liquid inlet end of the floating two-way lock 4 is connected to the second liquid return channel 13; the second liquid inlet end of the floating two-way lock 4 is connected to the second liquid inlet channel 12; the control end of the floating two-way lock 4 is connected to the first liquid inlet channel 9 through a floating control channel 11.

[0032] When the propelling jack 1 extends, it is necessary to supply fluid to the rodless cavity 101 of the propelling jack. At this time, the fluid enters the rodless cavity 101 of the propelling jack. At the same time, the fluid in the rod cavity 102 of the propelling jack is discharged as the propelling jack 1 extends; when the propelling jack 1 retracts, it is necessary to supply fluid to the rod cavity 102 of the propelling jack. At this time, the fluid enters the rod cavity 102 of the propelling jack. At the same time, the fluid in the rodless cavity 101 of the propelling jack is discharged as the propelling jack 1 retracts; if the fluid in the rodless cavity 101 of the propelling jack cannot be discharged due to the closing of the flow channel, resulting in the inability to compress the space in the rodless cavity 101 of the propelling jack, then the propelling jack 1 cannot retract; if the fluid in the rod cavity 102 of the propelling jack cannot be discharged due to the closing of the flow channel, resulting in the inability to compress the space in the rod cavity 102 of the propelling jack, then the propelling jack 1 cannot extend; if the fluids in both the rodless cavity 101 and the rod cavity 102 of the propelling jack cannot be discharged, then the propelling jack 1 is in a locked state.

[0033] The principle of extension and retraction of the telescopic jack 2 is the same as that of the propelling jack 1, which will not be elaborated here.

[0034] In a schematic embodiment, the telescopic floating hydraulic system further includes a single-ended hydraulic check valve 3. The inlet end of the single-ended hydraulic check valve 3 is connected to the first return flow channel 10, the outlet end of the single-ended hydraulic check valve 3 is connected to the rod cavity 102 of the propelling jack, and the control end of the single-ended hydraulic check valve 3 is connected to the first inlet flow channel 9.

[0035] The single-ended hydraulic check valve 3 has an inlet end, an outlet end, and a control end. When the pressure at the control end does not reach the threshold value, the fluid supply can only go from the inlet end to the outlet end and cannot go from the outlet end to the inlet end, that is, it can only pass unidirectionally between the inlet end and the outlet end; when the pressure at the control end reaches the threshold value, the fluid supply can go from the inlet end to the outlet end and can also go from the outlet end to the inlet end, that is, it can pass bidirectionally between the inlet end and the outlet end.

[0036] When it is necessary to move the support, the first inlet flow channel 9 supplies fluid. At this time, the fluid enters the rodless cavity 101 of the propelling jack. At the same time, the pressure at the control end of the single-ended hydraulic check valve 3 reaches the threshold value, so that the fluid in the rod cavity 102 of the propelling jack can be discharged from the first return flow channel 10, and the propelling jack 1 extends; when the propelling jack 1 extends to the preset stroke, the first inlet flow channel 9 stops supplying fluid. At this time, the pressure at the control end of the single-ended hydraulic check valve 3 does not reach the threshold value, and the first return flow channel 10 supplies fluid. The fluid enters the rod cavity 102 of the propelling jack, and the fluid in the rodless cavity 101 of the propelling jack can be discharged from the first inlet flow channel 9, and the propelling jack 1 retracts. Repeating the above steps can complete the operation of moving the support.

[0037] The floating two-way lock 4 has two liquid inlet ends, two liquid outlet ends and one control end. It can supply liquid through the second liquid inlet channel 12 to control the extension of the telescopic jack 2; it can supply liquid through the second liquid return channel 13 to control the retraction of the telescopic jack 2. When the pressure at the control end does not reach the threshold value, the floating two-way lock 4 is in the locked state; when the pressure at the control end reaches the threshold value, the floating two-way lock 4 is in the floating state.

[0038] In a schematic embodiment, the floating two-way lock 4 includes: a first double-ended hydraulically controlled check valve 401 and a second double-ended hydraulically controlled check valve 402. The liquid outlet end of the first double-ended hydraulically controlled check valve 401 is connected to the rod chamber 202 of the telescopic jack; the liquid outlet end of the second double-ended hydraulically controlled check valve 402 is connected to the rodless chamber 201 of the telescopic jack; the liquid inlet end of the first double-ended hydraulically controlled check valve 401 is respectively connected to the second liquid return channel 13 and the first control end of the second double-ended hydraulically controlled check valve 402; the liquid inlet end of the second double-ended hydraulically controlled check valve 402 is respectively connected to the second liquid inlet channel 12 and the first control end of the first double-ended hydraulically controlled check valve 401; the second control ends of the first double-ended hydraulically controlled check valve 401 and the second double-ended hydraulically controlled check valve 402 are respectively connected to the first liquid inlet channel 9 through the floating control channel 11.

[0039] The double-ended hydraulically controlled check valve has one liquid inlet end, one liquid outlet end and two control ends. When the pressures at both control ends do not reach the threshold value, it can only pass unidirectionally from the liquid inlet end to the liquid outlet end; when the pressure at any one of the two control ends reaches the threshold value, that is, when the pressure at the first control end reaches the threshold value or the pressure at the second control end reaches the threshold value, the liquid can pass bidirectionally between the liquid inlet end and the liquid outlet end.

[0040] When the second liquid inlet channel 12 supplies liquid, the oil can pass from the liquid inlet end to the liquid outlet end of the second double-ended hydraulically controlled check valve 402 and enter the rodless chamber 201 of the telescopic jack. At the same time, the pressure at the first control end of the first double-ended hydraulically controlled check valve 401 reaches the threshold value, and the liquid can pass bidirectionally between the liquid inlet end and the liquid outlet end of the first double-ended hydraulically controlled check valve 401, so that the oil in the rod chamber 202 of the telescopic jack can be discharged to the second liquid return channel 13, and the telescopic jack 2 extends.

[0041] When the second liquid return channel 13 supplies liquid, the oil can pass from the liquid inlet end to the liquid outlet end of the first double-ended hydraulically controlled check valve 401 and enter the rod chamber 202 of the telescopic jack. At the same time, the pressure at the first control end of the second double-ended hydraulically controlled check valve 402 reaches the threshold value, and the liquid can pass bidirectionally between the liquid inlet end and the liquid outlet end of the second double-ended hydraulically controlled check valve 402, so that the oil in the rodless chamber 201 of the telescopic jack can be discharged to the second liquid inlet channel 12, and the telescopic jack 2 retracts.

[0042] When there is no liquid supply in the second liquid inlet channel 12 and the second liquid return channel 13, and there is also no liquid supply in the first liquid inlet channel 9, the pressures at the two control ends of the first double-ended hydraulically controlled check valve 401 and the second double-ended hydraulically controlled check valve 402 do not reach the threshold value. The first double-ended hydraulically controlled check valve 401 and the second double-ended hydraulically controlled check valve 402 can only pass unidirectionally, so that the hydraulic oil in the rodless cavity 201 and the rod cavity 202 of the telescopic jack cannot be discharged, and the telescopic jack 2 is in a locked state.

[0043] When there is no liquid supply in the second liquid inlet channel 12 and the second liquid return channel 13, but there is liquid supply in the first liquid inlet channel 9, the pressures at the second control ends of the first double-ended hydraulically controlled check valve 401 and the second double-ended hydraulically controlled check valve 402 reach the threshold value. The first double-ended hydraulically controlled check valve 401 and the second double-ended hydraulically controlled check valve 402 can pass bidirectionally, so that the hydraulic oil in the rodless cavity 201 and the rod cavity 202 of the telescopic jack can be discharged, and the telescopic jack 2 is in a floating state. That is to say, when moving the support, the push jack 1 and the telescopic jack 2 can be linked. That is, when the first liquid inlet channel 9 supplies liquid, the push jack 1 extends, and at the same time, the floating control of the telescopic jack 2 is realized, preventing the telescopic jack 2 from being damaged by overpressure due to external force caused by improper operation; at the same time, during the normal support moving process, the contraction distance of the telescopic jack 2 can be relaxed, without complete contraction, reducing the total time of the extending and retracting actions of the telescopic jack 2, and improving the operation efficiency.

[0044] In a schematic implementation manner, the number of the telescopic jacks 2 is at least 2, and at least 2 telescopic jacks 2 are connected in parallel. That is, the rodless cavities 201 of each telescopic jack 2 are connected to the same channel, and the rod cavities 202 of each telescopic jack 2 are connected to the same channel. Such a setting can control at least 2 telescopic jacks 2 at the same time, so that each telescopic jack 2 is in the same control state. By connecting multiple telescopic jacks 2 in parallel, the total supporting force can be significantly increased, so that it can meet greater load requirements.

[0045] In a schematic implementation manner, a stroke sensor 103 is provided on the push jack 1, and an electromagnetic throttle valve 5 is provided on the first liquid inlet channel 9; the stroke sensor 103 is used to detect the extended length of the push jack 1, and when reaching a predetermined position, send a control signal to the electromagnetic throttle valve 5; the electromagnetic throttle valve 5 is used to reduce the flow rate of the first liquid inlet channel 9 to a preset ratio when receiving the control signal.

[0046] After the push jack 1 is extended to a certain length, that is, it reaches a predetermined position, the stroke sensor 103 outputs a control signal to the electromagnetic throttle valve 5, and the electromagnetic throttle valve 5 is energized to throttle the first liquid inlet channel 9, which can slow down the extension speed of the push jack 1, avoid the inertia force generated by the sudden stop of the hydraulic support when the hydraulic support is quickly moved under a large flow rate, and ensure that the telescopic jack in the floating state will not be maliciously extended by the inertia force.

[0047] In an illustrative embodiment, the predetermined position is 0.4-0.7 of the preset stroke of the push jack 1. For example, if the preset stroke of the push jack 1 is 100 mm, when the push jack 1 extends to 40 mm, the predetermined position is 0.4 of the preset stroke of the push jack 1, and the stroke sensor 103 outputs a control signal; or, if the preset stroke of the push jack 1 is 100 mm, when the push jack 1 extends to 50 mm, the predetermined position is 0.5 of the preset stroke of the push jack 1, and the stroke sensor 103 outputs a control signal; or, if the preset stroke of the push jack 1 is 100 mm, when the push jack 1 extends to 70 mm, the predetermined position is 0.7 of the preset stroke of the push jack 1, and the stroke sensor 103 outputs a control signal.

[0048] In an illustrative embodiment, the preset ratio is 0.3-0.8. For example: the liquid supply flow rate of the first liquid inlet channel 9 is 100mL / s. When a control signal is received, the electromagnetic throttle valve 5 reduces the liquid supply flow rate of the first liquid inlet channel 9 to 30mL / s, that is, the preset ratio is 0.3; or, the liquid supply flow rate of the first liquid inlet channel 9 is 100mL / s. When a control signal is received, the electromagnetic throttle valve 5 reduces the liquid supply flow rate of the first liquid inlet channel 9 to 50mL / s, that is, the preset ratio is 0.5; or, the liquid supply flow rate of the first liquid inlet channel 9 is 100mL / s. When a control signal is received, the electromagnetic throttle valve 5 reduces the liquid supply flow rate of the first liquid inlet channel 9 to 80mL / s, that is, the preset ratio is 0.8.

[0049] In an exemplary embodiment, a stop valve 6 is provided on the floating control flow channel 11. When the stop valve 6 is opened, the floating control flow channel 11 can control the floating two-way lock 4 to make the telescopic jack 2 enter a floating state; when the stop valve 6 is closed, the floating control flow channel 11 cannot control the floating two-way lock 4. Whether linkage floating control is required can be adjusted and set by the stop valve 6 according to actual needs.

[0050] In a schematic embodiment, a first safety valve 7 is provided on the flow channel where the liquid outlet end of the floating two-way lock 4 is connected to the rodless cavity 201 of the telescopic jack. The first safety valve 7 is used to limit the maximum pressure of the rodless cavity 201 of the telescopic jack. When the pressure in the rodless cavity 201 of the telescopic jack exceeds the limit, the first safety valve 7 opens to discharge the hydraulic oil, avoiding damage to the telescopic jack 2 caused by external force impact.

[0051] In a schematic embodiment, a second safety valve 8 is provided on the flow channel where the liquid outlet end of the single-ended hydraulically controlled one-way valve 3 is connected to the rod cavity 102 of the pushing jack. The second safety valve 8 is used to limit the maximum pressure of the rod cavity 102 of the pushing jack. When the pressure in the rod cavity 102 of the pushing jack exceeds the limit, the second safety valve 8 opens to discharge the hydraulic oil, avoiding damage to the pushing jack 1 caused by external force impact.

[0052] Based on the telescopic floating hydraulic system provided in the above embodiments, the second aspect of the present application also provides a hydraulic support, as Figure 2 shown, including the telescopic floating hydraulic system of the above embodiments. Since the hydraulic support provided in this embodiment has the telescopic floating hydraulic system provided in any of the above embodiments, the hydraulic support has all the beneficial effects of the telescopic floating hydraulic system provided in any of the above embodiments, which will not be elaborated here.

[0053] In the description of the present application, it should be understood that the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present application, "a plurality" means two or more unless otherwise specifically defined.

[0054] In the present application, unless otherwise clearly specified and limited, the terms "mounted", "connected", "connected to", "fixed" and other terms should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium; it may be the internal communication of two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0055] In this application, unless otherwise clearly defined and limited, a first feature being "on" or "under" a second feature may mean that the first and second features are in direct contact, or that the first and second features are indirectly in contact through an intermediate medium. Moreover, a first feature being "above", "over" and "on top of" a second feature may mean that the first feature is directly above or obliquely above the second feature, or merely means that the horizontal height of the first feature is higher than that of the second feature. A first feature being "under", "below" and "beneath" a second feature may mean that the first feature is directly below or obliquely below the second feature, or merely means that the horizontal height of the first feature is lower than that of the second feature.

[0056] In the description of this specification, the description of terms such as "one embodiment", "some embodiments", "embodiment", "exemplary embodiment", "example", "specific example" or "some examples", etc. means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of this application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0057] Although the embodiments of this application have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting this application. Those of ordinary skill in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A telescopic floating hydraulic system, characterized in that: include: A push jack (1), a telescopic jack (2) and a floating two-way lock (4), wherein the push jack (1) comprises: a push jack rodless chamber (101) and a push jack rod chamber (102), the push jack rodless chamber (101) is connected to a first liquid inlet channel (9); the push jack rod chamber (102) is connected to a first liquid return channel (10); The telescopic jack (2) comprises: a telescopic jack rodless chamber (201) and a telescopic jack rod chamber (202); the first liquid outlet end of the floating two-way lock (4) is connected to the telescopic jack rod chamber (202); the second liquid outlet end of the floating two-way lock (4) is connected to the telescopic jack rodless chamber (201); The first liquid inlet end of the floating two-way lock (4) is connected to the second liquid return channel (13); the second liquid inlet end of the floating two-way lock (4) is connected to the second liquid inlet channel (12); The control end of the floating bidirectional lock (4) is connected to the first liquid inlet channel (9) via a floating control channel (11).

2. A telescopic floating hydraulic system according to claim 1, characterized in that: The floating two-way lock (4) comprises: a first double-end hydraulically controlled one-way valve (401) and a second double-end hydraulically controlled one-way valve (402); the liquid outlet end of the first double-end hydraulically controlled one-way valve (401) is connected to the rod chamber (202) of the telescopic jack; the liquid outlet end of the second double-end hydraulically controlled one-way valve (402) is connected to the rodless chamber (201) of the telescopic jack; The liquid inlet end of the first double-end hydraulically controlled one-way valve (401) is respectively connected to the second liquid return channel (13) and the first control end of the second double-end hydraulically controlled one-way valve (402); the liquid inlet end of the second double-end hydraulically controlled one-way valve (402) is respectively connected to the second liquid inlet channel (12) and the first control end of the first double-end hydraulically controlled one-way valve (401); The second control end of the first double-end hydraulically controlled one-way valve (401) and the second control end of the second double-end hydraulically controlled one-way valve (402) are respectively connected to the first liquid inlet channel (9) via the floating control channel (11).

3. A telescopic floating hydraulic system as claimed in claim 1, characterized in that: The number of the telescopic jacks (2) is at least two, and at least two of the telescopic jacks (2) are connected in parallel.

4. A telescopic floating hydraulic system as claimed in claim 1, characterized in that: The push jack (1) is provided with a stroke sensor (103), and the first liquid inlet channel (9) is provided with an electromagnetic throttle valve (5); The stroke sensor (103) is used to detect the extended length of the push jack (1), and when a predetermined position is reached, a control signal is sent to the electromagnetic throttle valve (5); the electromagnetic throttle valve (5) is used to reduce the flow rate of the first liquid inlet channel (9) to a preset ratio when receiving the control signal.

5. A telescopic floating hydraulic system as claimed in claim 4, characterized in that: The predetermined position is 0.4-0.7 of the preset stroke of the push jack (1); and the preset ratio is 0.3-0.

8.

6. A telescopic floating hydraulic system as claimed in claim 1, characterized in that: It also comprises a single-end hydraulically controlled one-way valve (3), wherein the liquid inlet end of the single-end hydraulically controlled one-way valve (3) is connected to the first liquid return channel (10), the liquid outlet end of the single-end hydraulically controlled one-way valve (3) is connected to the rod chamber (102) of the push jack, and the control end of the single-end hydraulically controlled one-way valve (3) is connected to the first liquid inlet channel (9).

7. A telescopic floating hydraulic system as claimed in claim 1, characterized in that: The floating control flow channel (11) is provided with a stop valve (6).

8. A telescopic floating hydraulic system as claimed in claim 1, characterized in that: A first safety valve (7) is provided on the flow passage connecting the liquid outlet end of the floating two-way lock (4) and the rodless chamber (201) of the telescopic jack.

9. A telescopic floating hydraulic system as claimed in claim 6, characterized in that: A second safety valve (8) is provided on the flow passage connecting the liquid outlet end of the single-end hydraulically controlled one-way valve (3) and the rod chamber (102) of the push jack.

10. A hydraulic support, characterized in that: include: A telescopic floating hydraulic system as claimed in any one of claims 1 to 9.

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