Double-piston pushing hydraulic cylinder

Abstract

The invention discloses a double-piston pushing hydraulic cylinder which comprises a cylinder cover, a cylinder bottom, a cylinder barrel, a first guide sleeve, a second guide sleeve, a sleeve, a piston rod, a first piston and a second piston, wherein the first guide sleeve, the second guide sleeve, the sleeve, the piston rod, the first piston and the second piston are installed in the cylinder barrel. The first guide sleeve and the second guide sleeve are installed at the end close to the cylinder cover and the middle of the cylinder barrel respectively, and the sleeve is installed between the first guide sleeve and the second guide sleeve. The piston rod sequentially penetrates through the first guide sleeve, the sleeve and the second guide sleeve to be installed in the cylinder barrel, the first piston is installed at the end of the piston rod, and the second piston is installed in the middle of the piston rod and located at the left end of the second guide sleeve. On the premise that the diameter of the cylinder body is not changed, thrust can be improved through the synergistic effect of the double pistons, and the requirement for large thrust in a limited space is met. The built-in oil duct structure simplifies the layout of the hydraulic system and prevents external pipelines from occupying the installation space. Through the matching design of the double guide sleeves and the sleeve, the straightness and the stability of the movement of the piston rod are ensured, and a structural basis is provided for high-precision control.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of hydraulic cylinders, in particular to a double-piston push hydraulic cylinder. BACKGROUND

[0002] In the field of engineering machinery, the hydraulic cylinder as the core executive component directly affects the working effect of the equipment. With the development of industrial technology, special working conditions have put forward higher requirements for the hydraulic cylinder, especially the demand for realizing large thrust in limited space is increasingly prominent. The traditional hydraulic cylinder usually adopts the way of increasing the cylinder diameter or improving the system pressure to realize large thrust, but this will lead to the increase of equipment volume and system cost, and it is difficult to implement in space-limited working conditions. The existing single-piston hydraulic cylinder has inherent limitations in thrust control and cannot meet the demand for compact large-thrust hydraulic executive components in special fields such as aerospace. In addition, the flow compensation of the conventional hydraulic cylinder needs to additionally configure components such as hydraulic control check valve and accumulator, which increases the system complexity and maintenance cost. How to effectively improve the thrust of the hydraulic cylinder while maintaining the compactness of the system has become a technical problem to be solved in the field. SUMMARY

[0003] Therefore, the present application provides a double-piston push hydraulic cylinder which has the advantages of compact structure and large thrust.

[0004] To achieve the above-mentioned purpose, the present application provides the following technical scheme: A double-piston push hydraulic cylinder, comprising: a cylinder cover, a cylinder bottom, a cylinder barrel, and a first guide sleeve, a second guide sleeve, a sleeve, a piston rod, a first piston and a second piston installed in the cylinder barrel; the first guide sleeve and the second guide sleeve are respectively installed at one end close to the cylinder cover and the middle part of the cylinder barrel, and the sleeve is installed between the first guide sleeve and the second guide sleeve; the piston rod is installed in the cylinder barrel in sequence through the first guide sleeve, the sleeve and the second guide sleeve, the first piston is installed at the end of the piston rod, and the second piston is installed at the middle part of the piston rod and at the left end of the second guide sleeve.

[0005] Preferably, the first piston and the cylinder bottom have a first oil cavity, the second piston and the second guide sleeve have a second oil cavity, and the piston rod is internally provided with an internal oil passage, and the first oil cavity and the second oil cavity are connected in communication through the internal oil passage.

[0006] Preferably, the cylinder bottom is provided with an oil inlet, and the oil inlet is connected in communication with the first oil cavity.

[0007] Preferably, the double-piston push hydraulic cylinder further comprises a balance control valve, and the balance control valve is installed at the oil inlet.

[0008] Preferably, the double-piston push hydraulic cylinder further comprises a displacement sensor installed in the cylinder bottom for measuring the displacement position of the piston rod.

[0009] Preferably, a data recovery lead of the displacement sensor is led out from the cylinder bottom.

[0010] Preferably, the cylinder bottom is welded and fixed between the cylinder barrel.

[0011] Preferably, the piston rod is divided into a thick rod section and a thin rod section, the thick rod section is located between the ear ring of the piston rod and the first guide sleeve, the thin rod section is located between the first guide sleeve and the cylinder bottom, and the diameter of the thick rod section is greater than that of the thin rod section.

[0012] Preferably, the first piston is installed at the right end of the thin rod section, the second piston is installed at the right end of the thick rod section, and the second guide sleeve is installed at the left end of the thin rod section.

[0013] Preferably, the radial thickness of the first piston is greater than that of the second piston.

[0014] The beneficial effects of the present application are that, compared with the prior art, the present application can realize the multiplication of the pushing force through the cooperation of the double pistons without changing the diameter of the cylinder body, meet the demand of large pushing force in limited space, simplify the layout of the hydraulic system through the built-in oil way structure, and avoid the occupation of the installation space by the external pipeline. The cooperation design of the double guide sleeves and the sleeve ensures the straightness and stability of the movement of the piston rod, and provides a structural basis for high-precision control. The scheme is especially suitable for the execution mechanism scene in the aviation equipment which needs compact layout, high load and precise positioning.

[0015] Additional aspects and advantages of the present application will be partially given in the following description, partially become obvious from the following description, or be known by the practice of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 is a sectional view of the double-piston push hydraulic cylinder of the present application.

[0017] REFERENCE NUMERALS: 1, first guide sleeve; 2, cylinder barrel; 3, sleeve; 4, piston rod; 5, second piston; 6, second guide sleeve; 7, displacement sensor; 8, first piston; 9, balance control valve; 10, cylinder bottom. DETAILED DESCRIPTION

[0018] Embodiments of the present application are described below in the detailed description and illustrated in the accompanying drawings by which like or similar elements, e.g., components, features or functions, are designated with the same reference numerals throughout the several views. The embodiments described below are exemplary in nature and are intended to be illustrative of the present application rather than to be limiting of the present application.

[0019] Furthermore, the terms "first", "second", and the like, do not denote any

[0020] Reference is made below to Figure 1 A double-piston push hydraulic cylinder in an embodiment of the present application is described.

[0021] A double-piston push hydraulic cylinder in an embodiment of the present application is disclosed, comprising a cylinder head, a cylinder bottom 10, a cylinder barrel 2, a first guide sleeve 1, a second guide sleeve 6, a sleeve 3, a piston rod 4, a first piston 8 and a second piston 5 installed in the cylinder barrel 2; the first guide sleeve 1 and the second guide sleeve 6 are installed at one end close to the cylinder head and the middle of the cylinder barrel 2 respectively, and the sleeve 3 is installed between the first guide sleeve 1 and the second guide sleeve 6; the piston rod 4 is installed in the cylinder barrel 2 by passing through the first guide sleeve 1, the sleeve 3 and the second guide sleeve 6 in sequence, the first piston 8 is installed at the end of the piston rod 4, and the second piston 5 is installed at the middle of the piston rod 4 and at the left end of the second guide sleeve 6; the first piston 8 and the cylinder bottom 10 have a first oil cavity therebetween, the second piston 5 and the second guide sleeve 6 have a second oil cavity therebetween, and the piston rod 4 is provided with an internal oil passage; the cylinder bottom 10 is provided with an oil inlet, and the oil inlet is in communication with the first oil cavity.

[0022] The first guide sleeve 1 refers to an annular guide component arranged at the end of the cylinder barrel 2 close to the cylinder head, the inner hole of which is in sliding fit with the piston rod 4 to limit the radial deviation of the piston rod 4. The second guide sleeve 6 refers to an annular guide component arranged at the middle of the cylinder barrel 2 to separate the internal space of the cylinder barrel 2 to form the second oil cavity. The sleeve 3 refers to a cylindrical structure installed between the two guide sleeves, which can be processed by a stainless steel pipe, to fix the axial position of the second guide sleeve 6 and form the oil cavity separation. The internal oil passage refers to a through hole along the axis of the piston rod 4 to realize the hydraulic connection of the two oil cavities. The first oil cavity refers to a closed space surrounded by the end face of the first piston 8 and the cylinder bottom 10, and the second oil cavity refers to a closed space surrounded by the end face of the second piston 5 and the second guide sleeve 6.

[0023] Specifically, when the pressure oil enters the first oil chamber through the cylinder bottom 10 inlet, the oil pressure acts on the end faces of the first piston 8 and the second piston 5 at the same time. Because the first oil chamber and the second oil chamber are connected through the oil channel inside the piston rod 4, the two pistons generate a same-direction thrust under the action of the oil pressure, forming a superimposed force to push the piston rod 4 to extend. During the retraction process, the reverse oil pressure acts on the other side end faces of the two pistons, realizing the synchronous retraction of the double pistons. The matching structure of the second guide sleeve 6 and the sleeve 3 ensures the axial positioning accuracy of the two pistons during movement, avoiding the off-load phenomenon in the thrust transmission process. The guide sleeve arranged in the middle of the cylinder barrel 2 effectively shortens the cantilever length of the piston rod 4, improving the movement stability.

[0024] Compared with the prior art, the traditional single-piston hydraulic cylinder only bears the oil pressure through a single piston face, while the present scheme increases the effective action area by about one time through the double-piston structure, significantly improving the thrust under the same oil pressure. In the prior art, external pipelines need to be arranged to realize the oil supply of the double oil chambers, and the present scheme adopts an internal oil channel design, eliminating the occupation of the installation space by the external connecting parts. The combination structure of the guide sleeve and the sleeve 3 can accurately control the axial movement trajectory of the double pistons compared with the traditional single guide sleeve layout, avoiding the problem of movement out of synchronization caused by too large distance between the pistons.

[0025] Through the above technical scheme, the present application can realize the multiplication of the thrust through the cooperative action of the double pistons without changing the diameter of the cylinder body, meeting the demand for large thrust in limited space. The internal oil channel structure simplifies the layout of the hydraulic system, avoiding the occupation of the installation space by the external pipelines. The cooperation design of the double guide sleeves and the sleeve 3 ensures the straightness and stability of the movement of the piston rod 4, providing a structural basis for high-precision control. The present scheme is especially suitable for the execution mechanism scene in the aviation equipment that needs compact layout, high load and precise positioning.

[0026] In some embodiments, for example Figure 1 As shown, the double-piston thrust hydraulic cylinder further includes a balance control valve 9 installed at the oil inlet. The balance control valve 9 refers to a valve capable of dynamically adjusting the pressure and flow of hydraulic oil, which can be realized by a proportional valve or a servo valve, and the valve core opening is controlled by an electric signal to match the preset pressure threshold. The valve is integrated at the oil inlet of the cylinder bottom 10, directly communicating with the first oil chamber.

[0027] Specifically, the balance control valve 9 remains closed when the oil pressure does not reach the preset value, preventing insufficient pressure from causing the piston rod 4 to move behind schedule; when the pressure reaches the preset value, the valve core opens and dynamically adjusts the flow, ensuring that the double pistons are synchronized in force. This valve forms a closed-loop control with the displacement sensor 7, which receives real-time displacement data of the piston rod 4 and adjusts the valve opening, eliminating the impact of oil pulsation on displacement accuracy. The oil enters the first and second oil chambers through the internal oil channel, and the balance control valve 9 continuously maintains stable oil pressure during the double-piston pushing process, avoiding fluctuations in pushing force.

[0028] Through the above technical solutions, the present application solves the problem of insufficient displacement control accuracy of the piston rod 4 caused by oil pressure fluctuations or unstable flow, and ensures stable double-piston pushing force, while simplifying the structure of the hydraulic system and meeting the high-precision control requirements in limited space.

[0029] In some embodiments, for example Figure 1 As shown, the double-piston pushing hydraulic cylinder also includes a displacement sensor 7 installed in the cylinder bottom 10 for measuring the displacement position of the piston rod 4. The displacement sensor 7 refers to a measuring device for detecting the linear displacement change of the piston rod 4, which can be implemented using a magnetostrictive or photoelectric sensor. The measuring rod extends axially into the interior of the piston rod 4, and the displacement signal is captured in real time through a non-contact measurement method. The sensor body is embedded or fixedly connected inside the cylinder bottom 10 structure, and the sensor is axially aligned with the movement track of the piston rod 4 through the installation hole reserved on the end face of the cylinder bottom 10, ensuring that the measurement reference coincides with the hydraulic cylinder axis.

[0030] Specifically, the displacement sensor 7 measuring rod extends into the interior cavity of the piston rod 4, and when the piston rod 4 undergoes axial displacement, the sensor generates an electrical signal by detecting changes in magnetic field strength or differences in light signal reflection angle. This signal is transmitted to the external control system through data leads. The control unit dynamically adjusts the opening of the balance control valve 9 according to the displacement feedback value, forming a closed-loop control circuit to ensure that the oil flow matches the movement speed of the piston rod 4 in real time. Since the sensor is directly integrated inside the cylinder bottom 10, the distance between its installation position and the end of the piston rod 4 is shortened, avoiding the accumulation of measurement errors caused by external vibration interference, and the axial alignment design eliminates the cosine error caused by radial offset.

[0031] Through the above technical solutions, the present application realizes real-time high-precision detection of the displacement of the piston rod 4, and cooperates with the flow regulation function of the balance control valve 9 to meet the dual requirements of large pushing force and high precision in limited space, especially suitable for motion control scenarios of precision actuating mechanisms in aviation equipment.

[0032] In some embodiments, for example Figure 1As shown, the data recovery lead of the displacement sensor 7 is drawn out from the cylinder bottom 10. The data recovery lead refers to a wire for transmitting the measurement signal of the displacement sensor 7, which functions to transmit the position signal of the piston rod 4 collected by the displacement sensor 7 to an external control unit. The drawing out from the cylinder bottom 10 refers to drawing the data recovery lead out from the fixed end of the hydraulic cylinder, which can be achieved by setting a sealed threading hole or an integrated terminal on the cylinder bottom 10, and functions to reduce mechanical damage to the lead caused by vibration or moving parts through the structural stability of the fixed end.

[0033] Specifically, the displacement sensor 7 is installed inside the cylinder bottom 10, and the measurement rod thereof extends into the piston rod 4 to monitor the displacement change in real time. The data recovery lead extends outward through a sealed channel preset on the cylinder bottom 10, which is encapsulated by sealing glue or an elastic sealing ring to ensure that the oil does not leak. Since the cylinder bottom 10 is fixed to the cylinder barrel 2 by welding, the structural rigidity here is high, and the lead will not be affected by the expansion or vibration of the cylinder barrel 2 during transmission. At the same time, the cylinder bottom 10 is installed at the oil inlet position of the hydraulic system, and the internal oil passage thereof is directly connected to the external control valve, so the lead layout is separated from the oil passage to avoid signal interference.

[0034] Through the above technical solutions, the application realizes the stability and reliability of the signal transmission of the displacement sensor 7, reduces the risk of signal distortion caused by mechanical vibration or oil leakage, and at the same time maintains the sealing and integrity of the overall structure of the hydraulic cylinder.

[0035] In some embodiments, for example Figure 1 As shown, the cylinder bottom 10 and the cylinder barrel 2 are fixed by welding.

[0036] Specifically, the continuous weld formed by the welding fixation covers the annular joint surface of the cylinder bottom 10 and the cylinder barrel 2, so that the two are rigidly connected under axial and radial loads. The contact surface of the cylinder bottom 10 and the cylinder barrel 2 after welding forms a metallurgical bonding layer, eliminating the risk of sealing failure caused by insufficient pre-tightening force in traditional bolt connection. Under the action of high-pressure oil, the overall deformation coordination of the welded structure is better than that of the split connection, avoiding the wear of the sealing ring or the cracking of the connection surface caused by local stress concentration. In addition, the welding process does not need to process threaded holes or flange matching surfaces, reducing the positioning error in the assembly process and ensuring the coaxiality of the inner wall of the cylinder barrel 2 and the movement track of the piston rod 4.

[0037] Through the above technical solutions, the application effectively improves the sealing reliability and structural bearing capacity of the hydraulic cylinder, reduces the risk of hydraulic oil leakage caused by connection failure, simplifies the assembly process and improves the coaxiality of the cylinder body assembly, and provides a basic guarantee for the stable movement of the piston rod 4.

[0038] In some embodiments, for example Figure 1As shown, the piston rod 4 is divided into a thick rod section and a thin rod section, the thick rod section is located between the ear ring of the piston rod 4 and the first guide sleeve 1, and the thin rod section is located between the first guide sleeve 1 and the cylinder bottom 10, the diameter of the thick rod section is greater than that of the thin rod section. The first piston 8 is installed at the right end of the thin rod section, the second piston 5 is installed at the right end of the thick rod section, and the second guide sleeve 6 is installed at the left end of the thin rod section. The radial thickness of the first piston 8 is greater than that of the second piston 5.

[0039] Other configurations and operations of the double-piston push hydraulic cylinder according to the embodiments of the present application are known to those skilled in the art, and will not be described in detail here.

[0040] In the description of the present specification, the description of the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" and the like 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 the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples. In addition, different embodiments or examples described in the present specification and the features of different embodiments or examples can be combined and combined by those skilled in the art without contradiction.

[0041] Although the embodiments of the present application have been shown and described, those skilled in the art can understand that various changes, modifications, replacements and variations can be made to the embodiments without departing from the principles and purposes of the present application, and the scope of the present application is defined by the claims and their equivalents.

Claims

1. A double-piston thrust hydraulic cylinder, characterized in that: include: A cylinder head, a cylinder bottom, a cylinder barrel, and a first guide sleeve, a second guide sleeve, a sleeve, a piston rod, a first piston, and a second piston installed in the cylinder barrel; The first guide sleeve and the second guide sleeve are respectively installed at one end close to the cylinder head and the middle of the cylinder barrel, and the sleeve is installed between the first guide sleeve and the second guide sleeve; The piston rod passes through the first guide sleeve, the sleeve, and the second guide sleeve in sequence and is installed in the cylinder. The first piston is installed at the end of the piston rod, and the second piston is installed in the middle of the piston rod and is located at the left end of the second guide sleeve.

2. The double-piston thrust hydraulic cylinder according to claim 1, characterized in that: A first oil chamber is provided between the first piston and the cylinder bottom, a second oil chamber is provided between the second piston and the second guide sleeve, an internal oil passage is provided inside the piston rod, and the first oil chamber and the second oil chamber are connected through the internal oil passage.

3. The double-piston thrust hydraulic cylinder according to claim 2, characterized in that: The cylinder bottom is provided with an oil inlet, which is communicated with the first oil chamber.

4. The double-piston thrust hydraulic cylinder according to claim 3, characterized in that: It also includes a balancing control valve, which is installed at the oil inlet.

5. The double-piston thrust hydraulic cylinder according to claim 1, characterized in that: It also includes a displacement sensor, which is installed in the cylinder bottom and is used to measure the displacement position of the piston rod.

6. The double-piston thrust hydraulic cylinder according to claim 5, characterized in that: The data recovery lead of the displacement sensor is led out from the bottom of the cylinder.

7. The double-piston thrust hydraulic cylinder according to claim 1, characterized in that: The cylinder bottom and the cylinder barrel are welded and fixed.

8. The double-piston thrust hydraulic cylinder according to claim 1, characterized in that: The piston rod is divided into a thick rod section and a thin rod section. The thick rod section is located between the earring of the piston rod and the first guide sleeve, and the thin rod section is located between the first guide sleeve and the cylinder bottom. The diameter of the thick rod section is larger than that of the thin rod section.

9. The double-piston thrust hydraulic cylinder according to claim 8, characterized in that: The first piston is installed at the right end of the thin rod section, the second piston is installed at the right end of the thick rod section, and the second guide sleeve is installed at the left end of the thin rod section.

10. The double-piston thrust hydraulic cylinder according to claim 9, characterized in that: The radial thickness of the first piston is greater than the radial thickness of the second piston.

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