A speed-increasing composite hydraulic cylinder with stroke monitoring and differential return

Abstract

This invention discloses a speed-increasing composite hydraulic cylinder with stroke monitoring and differential return, relating to the field of hydraulic cylinder technology. It includes a cylinder body, an integrated hydraulic circuit block, and a stroke monitoring component. The cylinder body comprises an outer cylinder barrel, a hollow main piston rod, a piston, a sealing guide assembly, a sub-cylinder hollow piston rod, a sub-piston, and a rear end cover of the outer cylinder barrel. A third oil port is provided on the rear end cover of the outer cylinder barrel. A first oil port is connected to a first cavity, a second oil port is connected to a second cavity, and a third oil port is connected to a third cavity. The integrated hydraulic circuit block is connected to the first, second, and third oil ports via oil pipes. The integrated hydraulic circuit block includes a working oil circuit, a differential connection channel, and an oil circuit switching valve group. The oil circuit switching valve group is used to switch between the working oil circuit and the differential connection channel. The differential connection channel is used to connect the first and second oil ports during the return stroke. This invention solves the problem that existing ordinary hydraulic cylinders cannot simultaneously achieve both no-load operating speed and load pushing capacity.

Description

Technical Field

[0001] This invention relates to the field of hydraulic cylinder technology, specifically a speed-increasing composite hydraulic cylinder with stroke monitoring and differential return. Background Technology

[0002] Speed-increasing hydraulic cylinders typically rely on differences in structural area to achieve rapid extension under no-load conditions and output greater thrust under load conditions. They are widely used in hydraulic execution scenarios requiring rapid action and high thrust output, such as engineering machinery and hydraulic pushing equipment. Existing similar speed-increasing cylinders mostly adopt a nested structure with a piston inside a hollow piston rod, and achieve speed-increasing and pressure-boosting actions by switching the oil inlet and outlet of different oil chambers.

[0003] However, existing speed-increasing hydraulic cylinders mostly focus on speed-increasing and pressure-increasing control during the extension process. During the return stroke, they usually still rely on conventional oil return to reset, resulting in a slow return speed. Furthermore, the actual extension and retraction stroke and operating status of the cylinder are not easily obtained in real time, leading to low equipment operating cycle efficiency and making it difficult to switch automated operating conditions and perform precise control based on the cylinder position.

[0004] Therefore, the present invention provides a speed-increasing composite hydraulic cylinder with stroke monitoring and differential return. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a speed-increasing composite hydraulic cylinder with stroke monitoring and differential return, thereby solving the aforementioned problems.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a speed-increasing composite hydraulic cylinder with stroke monitoring and differential return, comprising a cylinder body, an integrated hydraulic circuit block, and a stroke monitoring component. The cylinder body includes an outer cylinder, a hollow main piston rod, a piston, a sealing and guiding component, a sub-cylinder hollow piston rod, a sub-piston, and a rear end cover of the outer cylinder. The hollow main piston rod is slidably disposed within the outer cylinder. The piston is disposed at one end of the hollow main piston rod, and the piston divides the interior of the outer cylinder into a first cavity and a second cavity. The sub-cylinder hollow piston rod is disposed within the hollow main piston rod. One end of the sub-cylinder hollow piston rod is provided with the sub-piston, and the other end is fixedly disposed relative to the rear end cover of the outer cylinder. The sub-piston is slidably and sealingly disposed within the hollow main piston rod and is connected to the hollow main piston rod. A third cavity is formed between the inner walls of the piston rod. A first oil port is provided on the outer cylinder. A first oil port and a third oil port are provided on the rear end cover of the outer cylinder. The first oil port is connected to the first cavity, the second oil port is connected to the second cavity, and the third oil port is connected to the third cavity. The integrated oil circuit block is connected to the first oil port, the second oil port, and the third oil port through a first oil pipe, a second oil pipe, and a third oil pipe, respectively. The integrated oil circuit block is provided with a working oil circuit, a differential communication channel, and an oil circuit switching valve group. The oil circuit switching valve group is used to switch the working oil circuit and the differential communication channel. The differential communication channel is used to connect the second oil port and the third oil port under the return stroke condition. The stroke monitoring component is located on the outside of the outer cylinder and is connected and linked with the hollow main piston rod.

[0007] Preferably, the other end of the hollow piston rod of the sub-cylinder is fixedly connected to a sub-piston rod fixing flange, and the sub-piston rod fixing flange is fixedly installed on the rear end cover of the outer cylinder.

[0008] Preferably, the hollow piston rod of the sub-cylinder is provided with an oil passage, one end of which is connected to the third cavity and the other end is connected to the third oil port.

[0009] Preferably, the oil circuit switching valve group has a quick extension position, a pressure boosting position, and a differential return position. When the oil circuit switching valve group is in the quick extension position or the pressure boosting position, the differential communication channel is cut off. When the oil circuit switching valve group is in the differential return position, the differential communication channel is connected to the third oil port and the second oil port.

[0010] Preferably, the integrated hydraulic manifold block is separately disposed from the cylinder body, with the integrated hydraulic manifold block being externally located on one side of the cylinder body.

[0011] Preferably, the outer cylinder is provided with a replenishing valve, which is located on the replenishing oil line between the first oil port and the third oil port.

[0012] Preferably, the stroke monitoring component includes an encoder, a fixed bracket, and a follower transmission component. The fixed bracket is fixedly connected to the outer wall of the outer cylinder, the encoder is mounted on the fixed bracket, and the follower transmission component is fixedly connected to the hollow main piston rod and is drivenly connected to the detection end of the encoder.

[0013] Preferably, the follower transmission component is arranged along the axial direction of the outer cylinder, one end of the follower transmission component is fixedly connected to the extended end of the hollow main piston rod, and the other end corresponds to the detection end of the encoder.

[0014] Preferably, the fixed bracket is provided with an adjustment groove, and the encoder is slidably installed in the adjustment groove.

[0015] Preferably, the cylinder body is a single-stage telescopic structure, and the hollow main piston rod is an integral hollow piston rod.

[0016] Beneficial effects

[0017] Compared with the prior art, the present invention has the following advantages:

[0018] 1. This invention achieves the functions of rapid unloaded extension and load-boosting push of the hydraulic cylinder through the cooperation of the outer cylinder, hollow main piston rod, piston, sub-cylinder hollow piston rod, sub-piston, first cavity, second cavity and third cavity. It enables the hollow main piston rod to change the hydraulic action area according to different oil supply conditions, thereby solving the problem that existing ordinary hydraulic cylinders cannot simultaneously take into account the unloaded action speed and the load-boosting push capacity.

[0019] 2. This invention, through the coordination of an integrated oil circuit block, a first oil pipe, a second oil pipe, a third oil pipe, a first oil port, a second oil port, a third oil port, a working oil circuit, a differential connecting channel, and an oil circuit switching valve group, achieves the oil circuit switching function between rapid extension, pressurized pushing, and differential rapid return of the oil cylinder. This allows the oil cylinder to connect the second and third oil ports through the differential connecting channel to accelerate the retraction speed during the return stroke. This solves the problem that existing speed-increasing hydraulic cylinders rely heavily on conventional return oil reset for the return stroke, resulting in slow return speed and low operating cycle efficiency.

[0020] 3. This invention, through the cooperation of encoder, fixed bracket and follow-up transmission component, realizes real-time monitoring of the extension stroke, running status and action speed of hollow main piston rod, so that the mechanical displacement can be converted into a detection signal that can be recognized by power control system during the operation of hydraulic cylinder. This solves the problem that existing speed-increasing hydraulic cylinders lack stroke monitoring structure, making it difficult to perform accurate positioning, working condition switching and automatic control. Attached Figure Description

[0021] Figure 1This is a schematic diagram of the internal cross-section of the main body of a speed-increasing composite hydraulic cylinder with stroke monitoring and differential return provided by the present invention;

[0022] Figure 2 This is a schematic diagram of the independent, specially designed integrated hydraulic circuit block connection of a speed-increasing composite hydraulic cylinder with stroke monitoring and differential return provided by the present invention.

[0023] Figure 3 This is a schematic diagram of the overall assembly structure of a speed-increasing composite hydraulic cylinder with stroke monitoring and differential return provided by the present invention.

[0024] As shown in the figure:

[0025] 1. Outer cylinder; 2. Hollow main piston rod; 3. Piston; 4. Sealing guide assembly; 6. Second chamber; 7. First chamber; 8. Third chamber; 9. Hollow piston rod of sub-cylinder; 10. Sub-piston; 11. Sub-piston rod fixing flange; 12. Oil passage; 13. First oil pipe; 14. Second oil pipe; 15. Third oil pipe; 16. Encoder; 17. Fixed bracket; 18. Follow-up transmission component; 19. Outer cylinder rear end cover; 20. Second oil port; 21. First oil port; 22. Third oil port; 23. Oil replenishing valve; 25. Integrated oil circuit block. Detailed Implementation

[0026] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] Please see Figures 1-3This application proposes a speed-increasing composite hydraulic cylinder with stroke monitoring and differential return, including a cylinder body, an integrated hydraulic circuit block 25, and a stroke monitoring component. The cylinder body includes an outer cylinder 1, a hollow main piston rod 2, a piston 3, a sealing and guiding component 4, a sub-cylinder hollow piston rod 9, a sub-piston 10, and an outer cylinder rear end cover 19. The hollow main piston rod 2 is slidably disposed inside the outer cylinder 1, and the piston 3 is disposed at one end of the hollow main piston rod 2. The piston 3 divides the interior of the outer cylinder 1 into a first cavity 7 and a second cavity 6. The sub-cylinder hollow piston rod 9 is disposed inside the hollow main piston rod 2. One end of the sub-cylinder hollow piston rod 9 is provided with the sub-piston 10, and the other end is fixedly disposed relative to the outer cylinder rear end cover 19. The sub-piston 10 is slidably and sealingly disposed inside the hollow main piston rod 2 and is in contact with the inner wall of the hollow main piston rod 2. A third cavity 8 is formed. A second oil port 20 is provided on the outer cylinder 1. A first oil port 21 and a third oil port 22 are provided on the rear end cover 19 of the outer cylinder. The first oil port 21 is connected to the first cavity 7, the second oil port 20 is connected to the second cavity 6, and the third oil port 22 is connected to the third cavity 8. The integrated oil circuit block 25 is connected to the second oil port 20, the first oil port 21, and the third oil port 22 through the first oil pipe 13, the second oil pipe 14, and the third oil pipe 15, respectively. The integrated oil circuit block 25 is provided with a working oil circuit, a differential communication channel, and an oil circuit switching valve group. The oil circuit switching valve group is used to switch the working oil circuit and the differential communication channel. The differential communication channel is used to connect the third oil port 22 and the second oil port 20 in the return working condition. The stroke monitoring component is located on the outside of the outer cylinder 1 and is connected and linked with the hollow main piston rod 2.

[0028] It should be noted that the outer cylinder 1 described in this embodiment is used to accommodate the hollow main piston rod 2 and the piston 3. The piston 3 moves with the hollow main piston rod 2 inside the outer cylinder 1, dividing the interior of the outer cylinder 1 into a first cavity 7 and a second cavity 6. The sub-cylinder hollow piston rod 9 is located inside the hollow main piston rod 2. The sub-piston 10 cooperates with the inner wall of the hollow main piston rod 2 to form a third cavity 8. The first oil port 21, the second oil port 20, and the third oil port 22 correspond to the first cavity 7, the second cavity 6, and the third cavity 8, respectively. The integrated oil circuit block 25 is connected to the three oil ports through the first oil pipe 13, the second oil pipe 14, and the third oil pipe 15. The stroke monitoring component is set on the outside of the outer cylinder 1 and performs detection as the hollow main piston rod 2 extends and retracts.

[0029] Specifically, when the cylinder is working, the integrated oil circuit block 25 switches between different oil supply states through the oil circuit switching valve group, allowing hydraulic oil to enter the corresponding cavity in the first cavity 7, the second cavity 6, or the third cavity 8. When no-load rapid extension is required, the hollow main piston rod 2 drives the piston 3 to extend outward through the working oil circuit. When load boosting and pushing are required, the first cavity 7 participates in the thrust output through the piston 3, enabling the cylinder to obtain a greater pushing effect. When return is required, the differential connection channel connects the third oil port 22 and the second oil port 20, so that the third cavity 8 and the second cavity 6 form a differential return oil circuit, improving the retraction speed of the hollow main piston rod 2. In addition, the stroke monitoring component synchronously collects the extension and retraction state of the hollow main piston rod 2, thereby solving the problems of slow return speed, inflexible oil circuit switching, and inconvenient automatic control caused by the lack of stroke monitoring in the existing speed-increasing hydraulic cylinder.

[0030] Furthermore, such as Figure 1 and Figure 3 As shown, the other end of the hollow piston rod 9 of the sub-cylinder is fixedly connected to the sub-piston rod fixing flange 11, which is fixedly installed on the rear end cover 19 of the outer cylinder.

[0031] It should be noted that the sub-piston rod fixing flange 11 described in this embodiment is located at one end of the sub-cylinder hollow piston rod 9 near the rear end cover 19 of the outer cylinder. After the sub-piston rod fixing flange 11 is connected to the rear end cover 19 of the outer cylinder, the sub-cylinder hollow piston rod 9 can be fixed relative to the outer cylinder 1. The sub-piston 10 is located on the other side of the sub-cylinder hollow piston rod 9 and is located inside the hollow main piston rod 2.

[0032] Specifically, when the hollow main piston rod 2 moves telescopically relative to the outer cylinder 1, the hollow piston rod 9 of the sub-cylinder is held at the rear end cover 19 of the outer cylinder through the sub-piston rod fixing flange 11. The sub-piston 10 and the hollow main piston rod 2 slide relative to each other, so that the third cavity 8 can form a stable hydraulic action space with the movement of the hollow main piston rod 2. This solves the problem that the third cavity 8 is difficult to stably participate in the pressurization and pushing when the hollow piston rod 9 of the sub-cylinder lacks a fixed foundation.

[0033] Furthermore, such as Figures 1 to 3 As shown, an oil passage 12 is provided inside the hollow piston rod 9 of the sub-cylinder. One end of the oil passage 12 is connected to the third cavity 8, and the other end is connected to the third oil port 22.

[0034] It should be noted that the oil passage 12 described in this embodiment is located inside the hollow piston rod 9 of the sub-cylinder. One end of the oil passage 12 corresponds to the third cavity 8, and the other end corresponds to the third oil port 22 on the rear end cover 19 of the outer cylinder, so that the hydraulic oil entering through the third oil port 22 can enter the third cavity 8 through the hollow piston rod 9 of the sub-cylinder.

[0035] Specifically, under the pressure boosting and pushing condition, hydraulic oil enters the oil passage 12 through the third oil port 22, then enters the third cavity 8 and acts on the corresponding positions inside the sub-piston 10 and the hollow main piston rod 2, so that the third cavity 8 participates in the output thrust of the oil cylinder, thereby solving the problem that the effective pressure area is limited and the load pushing capacity is insufficient when relying solely on the inner cavity of the outer cylinder 1 for oil supply.

[0036] Furthermore, such as Figures 1 to 3 As shown, the oil circuit switching valve group has a quick extension position, a boosting push position, and a differential return position. When the oil circuit switching valve group is in the quick extension position or the boosting push position, the differential communication channel is cut off. When the oil circuit switching valve group is in the differential return position, the differential communication channel is connected to the third oil port 22 and the second oil port 20.

[0037] It should be noted that the oil circuit switching valve group described in this embodiment is set in the integrated oil circuit block 25. The oil circuit switching valve group can switch between the quick extension position, the boosting push position and the differential return position. The quick extension position and the boosting push position correspond to the working oil circuit, and the differential return position corresponds to the differential connection channel. When the differential connection channel is connected, the third oil port 22 and the second oil port 20 are connected through the oil circuit inside the integrated oil circuit block 25.

[0038] Specifically, when the hydraulic cylinder extends, the oil circuit switching valve group cuts off the differential connection channel, allowing the first chamber 7, the second chamber 6, and the third chamber 8 to complete rapid extension or pressurized pushing according to the corresponding working oil circuit. When the operation is completed and the return stroke is required, the oil circuit switching valve group switches to the differential return position, and the differential connection channel connects the third oil port 22 and the second oil port 20, allowing the third chamber 8 and the second chamber 6 to participate in the differential return stroke. This solves the problem that the existing speed-increasing hydraulic cylinder relies solely on conventional return oil for reset during the return stroke, resulting in a slow retraction speed.

[0039] Furthermore, such as Figures 1 to 3 As shown, the integrated oil circuit block 25 is set separately from the cylinder body, and the integrated oil circuit block 25 is placed separately on one side of the cylinder body.

[0040] It should be noted that the integrated oil circuit block 25 described in this embodiment is an independently arranged oil circuit component. It is connected to the second oil port 20, the first oil port 21 and the third oil port 22 on the cylinder body through the first oil pipe 13, the second oil pipe 14 and the third oil pipe 15. The integrated oil circuit block 25 does not need to be fixed on the outer cylinder 1 or the rear end cover 19 of the outer cylinder. It can be arranged on one side of the cylinder body according to the equipment installation space.

[0041] Specifically, during installation, the cylinder body can be installed in the hydraulic equipment's execution position, and the integrated oil circuit block 25 can be arranged in a position that is easy to connect and maintain. Then, the corresponding oil ports are connected through the first oil pipe 13, the second oil pipe 14, and the third oil pipe 15, so that the working oil circuit and the differential communication channel can be switched through the external oil circuit. This solves the problems of structural limitations, high modification difficulty, and inflexible installation layout when the traditional differential oil circuit is directly integrated at the end of the cylinder.

[0042] Furthermore, such as Figures 1 to 3 As shown, an oil replenishing valve 23 is provided on the outer cylinder 1, and the oil replenishing valve 23 is located on the oil replenishing line between the first oil port 21 and the third oil port 22.

[0043] It should be noted that the oil replenishing valve 23 described in this embodiment is set at the corresponding oil circuit position of the outer cylinder 1. The oil replenishing valve 23 is located on the oil replenishing oil circuit between the first oil port 21 and the third oil port 22, and is used to compensate the oil state of the first chamber 7 when the oil cylinder switches between different working conditions.

[0044] Specifically, during the rapid extension, pressurized push, or differential return of the hydraulic cylinder, the oil pressure and flow rate in the first chamber 7 will change with the working conditions. The oil replenishment valve 23 can replenish oil in the corresponding oil replenishment circuit or prevent local oil supply shortage, so that the hydraulic cylinder runs more smoothly during the working condition switching process. This solves the problem that the composite hydraulic cylinder may have local oil supply shortage when switching between multiple oil chambers, which affects the extension and retraction stability.

[0045] Furthermore, such as Figures 1 to 3 As shown, the stroke monitoring component includes an encoder 16, a fixed bracket 17, and a follower transmission component 18. The fixed bracket 17 is fixedly connected to the outer wall of the outer cylinder 1. The encoder 16 is mounted on the fixed bracket 17. The follower transmission component 18 is fixedly connected to the hollow main piston rod 2 and is connected to the detection end of the encoder 16.

[0046] It should be noted that the fixed bracket 17 described in this embodiment is set on the outer wall of the outer cylinder 1, the encoder 16 is installed on the fixed bracket 17, the follower transmission component 18 is connected to the hollow main piston rod 2, the follower transmission component 18 moves with the extension and retraction of the hollow main piston rod 2, and transmits the linear displacement of the hollow main piston rod 2 to the detection end of the encoder 16.

[0047] Specifically, when the hydraulic cylinder extends and retracts, the hollow main piston rod 2 drives the follower transmission component 18 to move synchronously. The follower transmission component 18 drives the encoder 16 to generate a detection signal, enabling the external electronic control system to obtain the extension and retraction stroke and operating status of the hollow main piston rod 2. This solves the problem that existing speed-increasing hydraulic cylinders lack an external stroke detection device, making it difficult to accurately know the actual extension length and operating speed of the cylinder.

[0048] Furthermore, such as Figures 1 to 3 As shown, the follower transmission component 18 is arranged along the axial direction of the outer cylinder 1. One end of the follower transmission component 18 is fixedly connected to the extended end of the hollow main piston rod 2, and the other end corresponds to the detection end of the encoder 16.

[0049] It should be noted that the follower transmission component 18 described in this embodiment is arranged along the axial direction of the outer cylinder 1. One end of the follower transmission component 18 is connected to the extended end of the hollow main piston rod 2, and the other end corresponds to the detection end of the encoder 16. The arrangement direction of the follower transmission component 18 is consistent with the extension and retraction direction of the hollow main piston rod 2, so that it can directly reflect the axial displacement change of the hollow main piston rod 2.

[0050] Specifically, when the hollow main piston rod 2 extends or retracts, the follower transmission component 18 moves synchronously along the axial direction of the outer cylinder 1. The detection end of the encoder 16 outputs a displacement signal according to the movement of the follower transmission component 18, so that the cylinder stroke detection is consistent with the actual extension and retraction direction. This solves the problem that when the detection transmission direction is inconsistent with the cylinder extension and retraction direction, it is easy to cause detection errors and inconvenience in alignment and debugging.

[0051] Furthermore, such as Figure 1 and Figure 3 As shown, the fixed bracket 17 has an adjustment groove, and the encoder 16 is slidably installed in the adjustment groove.

[0052] It should be noted that the adjustment slide described in this embodiment is set on the fixed bracket 17, the encoder 16 is installed in the adjustment slide, and the installation position can be adjusted along the adjustment slide so that the encoder 16 can be aligned and calibrated according to the actual position of the follower transmission component 18.

[0053] Specifically, during on-site installation or maintenance, the position of the encoder 16 relative to the follower transmission component 18 can be adjusted by adjusting the slide groove, so that the detection end of the encoder 16 and the follower transmission component 18 maintain a corresponding relationship, thereby solving the problem that when the fixed position of the encoder 16 is not adjustable, the installation error can easily affect the accuracy of the stroke detection.

[0054] Furthermore, such as Figure 1 and Figure 3 As shown, the main body of the cylinder is a single-stage telescopic structure, and the hollow main piston rod 2 is an integral hollow piston rod.

[0055] It should be noted that the cylinder body described in this embodiment adopts a single-stage telescopic structure. The hollow main piston rod 2 is an integral hollow piston rod, which cooperates with the piston 3 to form the main cylinder telescopic structure. Its interior is used to accommodate the hollow piston rod 9 of the sub-cylinder and the sub-piston 10, so that the hollow main piston rod 2 can be used as both the main telescopic component and the sub-cylinder cooperating component.

[0056] Specifically, the hollow main piston rod 2 performs single-stage linear extension and retraction within the outer cylinder 1. The piston 3 cooperates with the outer cylinder 1 to realize the extension and retraction action of the main oil cylinder. The hollow main piston rod 2 also cooperates with the sub-piston 10 to form a third cavity 8, which is used to participate in the force under the pressure boosting and pushing conditions. This solves the problems of numerous parts, complex coordination, and insufficient operational stability and assembly convenience in multi-stage extension and retraction structures.

[0057] Furthermore, any content not described in detail in this specification is existing technology known to those skilled in the art.

[0058] Working principle: During use, the integrated hydraulic circuit block 25 is connected to the second oil port 20, the first oil port 21, and the third oil port 22 via the first oil pipe 13, the second oil pipe 14, and the third oil pipe 15, respectively, allowing hydraulic oil to enter the second chamber 6, the first chamber 7, and the third chamber 8 accordingly. When extended under no-load, the hydraulic circuit switching valve group switches to the rapid extension position, causing the hollow main piston rod 2 to drive the piston 3 to extend rapidly along the outer cylinder 1. When pushed under load, the hydraulic circuit switching valve group switches to the booster push position, allowing hydraulic oil to enter the third chamber 8 and the first chamber 7 through the oil passage 12 in the hollow piston rod 9 of the sub-cylinder via the third oil port 22, with the sub-piston 10 and piston 3 participating in the thrust output. When the operation is completed and the return stroke is completed, the oil circuit switching valve group switches to the differential return position, so that the differential connection channel connects the third oil port 22 and the second oil port 20, thereby forming a differential return oil circuit between the third cavity 8 and the second cavity 6, which accelerates the retraction speed of the hollow main piston rod 2. At the same time, during the extension and retraction of the hollow main piston rod 2, it drives the follower transmission component 18 to move synchronously. The encoder 16 collects the cylinder stroke and operating status through the follower transmission component 18. Thus, through the cooperation of the cylinder body, the integrated oil circuit block 25 and the stroke monitoring component, the problems of slow return speed, limited differential oil circuit layout and lack of stroke monitoring in existing speed-increasing hydraulic cylinders are solved.

[0059] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0060] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A speed-increasing composite hydraulic cylinder with stroke monitoring and differential return, characterized in that, The system includes a cylinder body, an integrated hydraulic circuit block (25), and a stroke monitoring component. The cylinder body includes an outer cylinder barrel (1), a hollow main piston rod (2), a piston (3), a sealing guide component (4), a sub-cylinder hollow piston rod (9), a sub-piston (10), and an outer cylinder barrel rear end cap (19). The hollow main piston rod (2) is slidably disposed inside the outer cylinder barrel (1). The piston (3) is disposed at one end of the hollow main piston rod (2). The piston (3) partially compresses the inner portion of the outer cylinder barrel (1). The cylinder is divided into a first cavity (7) and a second cavity (6). The hollow piston rod (9) of the sub-cylinder is disposed inside the hollow main piston rod (2). One end of the hollow piston rod (9) of the sub-cylinder is provided with the sub-piston (10), and the other end is fixedly disposed relative to the rear end cover (19) of the outer cylinder. The sub-piston (10) is sealed and slidably disposed inside the hollow main piston rod (2) and forms a third cavity (8) between itself and the inner wall of the hollow main piston rod (2). The outer cylinder (1) The upper part is provided with a first oil port (21) and a second oil port (20), and the rear end cover (19) of the outer cylinder is provided with a third oil port (22). The first oil port (21) is connected to the first cavity (7), the second oil port (20) is connected to the second cavity (6), and the third oil port (22) is connected to the third cavity (8). The integrated oil circuit block (25) is connected to the second oil port (20) through oil pipes (13), (14), and (15) respectively. The first oil port (21) and the third oil port (22) are connected. The integrated oil circuit block (25) is provided with a working oil circuit, a differential communication channel and an oil circuit switching valve group. The oil circuit switching valve group is used to switch the working oil circuit and the differential communication channel. The differential communication channel is used to connect the first oil port (21) and the second oil port (20) in the return working condition. The stroke monitoring component is located on the outside of the outer cylinder (1) and is connected and linked with the hollow main piston rod (2).

2. The speed-increasing composite hydraulic cylinder with stroke monitoring and differential return as described in claim 1, characterized in that: The other end of the hollow piston rod (9) of the sub-cylinder is fixedly connected to a sub-piston rod fixing flange (11), which is fixedly installed on the rear end cover (19) of the outer cylinder.

3. The speed-increasing composite hydraulic cylinder with stroke monitoring and differential return as described in claim 1, characterized in that: The hollow piston rod (9) of the sub-cylinder is provided with an oil passage (12), one end of which is connected to the third cavity (8) and the other end is connected to the third oil port (22).

4. A speed-increasing composite hydraulic cylinder with stroke monitoring and differential return as described in claim 1, characterized in that: The oil circuit switching valve group has a quick extension position, a boosting push position and a differential return position. When the oil circuit switching valve group is in the quick extension position or the boosting push position, the differential communication channel is cut off. When the oil circuit switching valve group is in the differential return position, the differential communication channel is connected to the third oil port (22) and the second oil port (20).

5. A speed-increasing composite hydraulic cylinder with stroke monitoring and differential return as described in claim 1, characterized in that: The integrated oil circuit block (25) is separately disposed from the cylinder body, and the integrated oil circuit block (25) is placed separately on one side of the cylinder body.

6. A speed-increasing composite hydraulic cylinder with stroke monitoring and differential return as described in claim 1, characterized in that: The outer cylinder (1) is provided with a replenishing valve (23), which is located on the replenishing oil line between the first oil port (21) and the third oil port (22).

7. A speed-increasing composite hydraulic cylinder with stroke monitoring and differential return as described in claim 1, characterized in that: The stroke monitoring component includes an encoder (16), a fixed bracket (17), and a follower transmission component (18). The fixed bracket (17) is fixedly connected to the outer wall of the outer cylinder (1). The encoder (16) is mounted on the fixed bracket (17). The follower transmission component (18) is fixedly connected to the hollow main piston rod (2) and is connected to the detection end of the encoder (16) via a transmission.

8. A speed-increasing composite hydraulic cylinder with stroke monitoring and differential return as described in claim 7, characterized in that: The follower transmission component (18) is arranged along the axial direction of the outer cylinder (1). One end of the follower transmission component (18) is fixedly connected to the extended end of the hollow main piston rod (2), and the other end corresponds to the detection end of the encoder (16).

9. A speed-increasing composite hydraulic cylinder with stroke monitoring and differential return as described in claim 7, characterized in that: An adjustment groove is provided on the fixed bracket (17), and the encoder (16) is slidably installed in the adjustment groove.

10. A speed-increasing composite hydraulic cylinder with stroke monitoring and differential return as described in claim 1, characterized in that: The main body of the cylinder is a single-stage telescopic structure, and the hollow main piston rod (2) is an integral hollow piston rod.

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