Hydraulic cylinder buffering and sealing structure suitable for multiple working conditions

Abstract

The invention relates to the technical field of hydraulic cylinders, and discloses a hydraulic cylinder buffer sealing structure suitable for multiple working conditions, which comprises a cylinder body, a cylinder cover is connected to the front end of the cylinder body, a cylinder bottom is connected to the rear end of the cylinder body, a piston rod is arranged in the cylinder body, and a piston is connected to one end of the piston rod. A reinforcing piece is arranged between the piston and the piston rod, supporting shells are arranged at the two ends of the inner side of the cylinder body, and piezoelectric films are arranged on one sides of the supporting shells. The hydraulic cylinder is easy to apply and popularize in an existing system, the buffering process is smoother and more controllable, the extreme impact risk is reduced, active sealing is beneficial for reducing leakage, the working life of the hydraulic cylinder under the complex and changeable working conditions is prolonged, and the reliability of the whole system is improved.

Description

Technical Field

[0001] This invention relates to the field of hydraulic cylinder technology, specifically to a hydraulic cylinder buffer sealing structure applicable to multiple working conditions. Background Technology

[0002] Hydraulic cylinders typically require a buffer structure at the end of their stroke to prevent mechanical impact between the piston and the end cap, thereby reducing noise, vibration, and wear. Traditional buffer structures (such as fixed orifices and variable throttle valves) often have their buffering characteristics determined during manufacturing, making it difficult to adaptively adjust them according to actual operating conditions (such as changes in load and speed). This is especially problematic in applications with variable loads and frequent speed fluctuations. Fixed buffers are prone to insufficient buffering leading to impacts, or excessive buffering leading to stroke sluggishness and reduced efficiency. Furthermore, the static seal between the piston rod and the end cap is prone to failure due to wear after long-term use, resulting in leakage. Summary of the Invention

[0003] The purpose of this invention is to provide a hydraulic cylinder buffer sealing structure applicable to multiple working conditions, so as to solve the problems mentioned in the background art.

[0004] To achieve the above objectives, the present invention provides the following technical solution: A cylinder body is included, with a cylinder head connected to the front end and a cylinder bottom connected to the rear end. A piston rod is disposed inside the cylinder body, with a piston connected to one end of the piston rod. A reinforcing member is disposed between the piston and the piston rod. Support shells are disposed at both ends of the inner side of the cylinder body. A piezoelectric film is disposed on one side of the support shell. A mounting circuit board is disposed inside the support shell. A signal acquisition unit, a signal processing control unit, and a feedback unit are disposed on one side of the mounting circuit board. An electromagnetic coil is connected to the outer side of the piston. A power connection assembly is connected to one side of the electromagnetic coil. Multiple sets of buffer assemblies are disposed inside the piston. A sealing assembly is disposed inside the cylinder head. Connecting rings are disposed at the ends of the cylinder bottom and the piston rod that are far apart from each other.

[0005] Preferably, the signal acquisition unit includes a voltage follower chip, a charge amplifier, a filter component, and a feedback capacitor disposed on one side of the mounting circuit board. The charge amplifier is electrically connected to the piezoelectric film, and the signal acquisition unit is electrically connected to the signal processing control unit.

[0006] Preferably, the signal processing control unit includes a voltage reference chip, an operational amplifier, a voltage-controlled amplifier, a voltage-to-current converter chip, an MCU control chip, an analog-to-digital converter, and a feedback diode. The signal processing control unit is electrically connected to the buffer component and the feedback unit.

[0007] Preferably, the feedback unit includes a linear regulator, an isolated power supply module, a gate driver, and a power MOSFET, and the feedback unit is electrically connected to the sealing assembly.

[0008] Preferably, the sealing assembly includes a dielectric elastic ring, and both the inner and outer sides of the dielectric elastic ring are provided with fitting grooves, and flexible electrodes are provided in each fitting groove.

[0009] Preferably, the buffer assembly includes a movable groove formed inside the piston, a push plate slidably disposed in the movable groove, connecting rods connected to both sides of the push plate, a cone head connected to one end of each connecting rod, multiple sets of oil permeable holes formed on one side of the push plate, an inner sealing ring disposed on the surface of the push plate, an fitting groove formed on one side of the piston corresponding to the cone head, a second sealing ring disposed on the inner side of the piston, and magnetorheological fluid filled in the movable groove.

[0010] Preferably, the power connection assembly includes a mounting groove formed on one side of the piston, a compression spring is provided inside the mounting groove, a grounding seat is provided at one end of the compression spring, a power connection ball is rotatably provided inside the grounding seat, and a limit seat is provided at the top of the mounting groove.

[0011] Preferably, the top of the limiting seat has a through hole corresponding to the electric ball, the bottom of the grounding seat is provided with a wire, the wire is electrically connected to the electromagnetic coil, the piston surface is provided with a sealing sleeve corresponding to the electromagnetic coil, and sealing rings are provided at both ends, and multiple sets of conductive strips are provided on one side of the inner wall of the cylinder corresponding to the electric ball, the electric ball side has a through hole and is attached to the conductive strip.

[0012] Preferably, an oil permeable pipe is provided on one side of the support shell.

[0013] In summary, the beneficial effects of this invention are: This application uses a piezoelectric thin film to sense the end-impact force, and the processing circuit controls the current of the electromagnetic coil in real time to change the viscosity of the magnetorheological fluid, thereby dynamically adjusting the buffer damping. This achieves a leap from "fixed buffering" to "on-demand buffering," effectively coping with end-impact forces under different loads and speeds, balancing buffering effect and efficiency. By controlling the voltage applied to the dielectric elastomer sealing ring through a feedback unit, its clamping force can be actively adjusted to compensate for wear, enhance sealing reliability, and is expected to achieve better dynamic sealing under high-pressure conditions. The piezoelectric thin film, circuit, electromagnetic coil, magnetorheological fluid buffer component, and dielectric elastomer sealing ring are highly integrated into the cylinder without changing the basic shape and interface of the hydraulic cylinder, making it easy to apply and promote within existing systems. The buffering process is smoother and more controllable, reducing the risk of extreme impacts. Active sealing helps reduce leakage, and both together improve the working life of the hydraulic cylinder and the overall system reliability under complex and variable working conditions. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the overall structure of a hydraulic cylinder buffer sealing structure applicable to multiple working conditions according to the present invention; Figure 2 This is a side sectional view of a hydraulic cylinder buffer sealing structure applicable to multiple working conditions according to the present invention. Figure 3 This is a schematic diagram of the piston structure in a hydraulic cylinder buffer sealing structure applicable to multiple working conditions according to the present invention; Figure 4 for Figure 3 A schematic diagram of the side section structure; Figure 5 for Figure 4 Enlarged structural diagram of section A; Figure 6 for Figure 4 Enlarged structural diagram of section B; Figure 7 This is a schematic diagram of the internal structure of the support shell in a hydraulic cylinder buffer sealing structure applicable to multiple working conditions according to the present invention. Figure 8 This is a schematic diagram of the sealing component in a hydraulic cylinder buffer sealing structure applicable to multiple working conditions according to the present invention.

[0015] In the diagram: 1. Cylinder block; 2. Cylinder bottom; 3. Cylinder head; 4. Piston rod; 5. Piston; 6. Reinforcing member; 7. Support shell; 71. Oil permeable pipe; 8. Piezoelectric film; 9. Mounting circuit board; 10. Signal acquisition unit; 101. Voltage follower chip; 102. Charge amplifier; 103. Filter assembly; 104. Feedback capacitor; 11. Signal processing control unit; 111. Voltage reference chip; 112. Operational amplifier; 113. Voltage-controlled amplifier; 114. Voltage-to-current converter chip; 115. MCU control chip; 116. Analog-to-digital converter; 117. Feedback diode; 12. Feedback unit; 121. Linear regulator; 122. Isolated power supply module; 123. Gate driver; 124. Power MOSFET; 13. Sealing ring one; 14. Electromagnetic coil; 15. Power connection assembly; 151. Mounting slot; 152. Compression spring; 153. Grounding base; 154. Power ball; 155. Limiting seat; 156. Wire; 16. Sealing sleeve; 17. Movable groove; 18. Magnetorheological fluid; 19. Buffer assembly; 191. Push plate; 192. Connecting rod; 193. Cone; 194. Oil passage hole; 195. Inner sealing ring; 196. Fitting groove; 197. Sealing ring two; 20. Sealing assembly; 201. Dielectric elastic ring; 202. Fitting groove; 203. Flexible electrode; 21. Connecting ring; 22. Conductive strip. Detailed Implementation

[0016] 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.

[0017] Please see Figure 1-8 The present invention provides a technical solution comprising: a cylinder body 1, a cylinder head 3 connected to the front end of the cylinder body 1 and a cylinder bottom 2 connected to the rear end of the cylinder body 1, oil connection holes provided on one side of both the cylinder bottom 2 and the cylinder head 3, a piston rod 4 provided inside the cylinder body 1, a piston 5 connected to one end of the piston rod 4, a reinforcing member 6 provided between the piston 5 and the piston rod 4, support shells 7 provided at both ends of the inner side of the cylinder body 1, a piezoelectric film 8 provided on one side of the support shell 7, a mounting circuit board 9 provided inside the support shell 7, a signal acquisition unit 10, a signal processing control unit 11 and a feedback unit 12 provided on one side of the mounting circuit board 9, an electromagnetic coil 14 connected to the outer side of the piston 5, a power connection component 15 connected to one side of the electromagnetic coil 14, multiple sets of buffer components 19 provided inside the piston 5, a sealing component 20 provided inside the cylinder head 3, and connecting rings 21 provided at the ends of the cylinder bottom 2 and the piston rod 4 that are far apart from each other.

[0018] Reference Figure 7 As shown, the signal acquisition unit 10 includes a voltage follower chip 101, a charge amplifier 102, a filter component 103, and a feedback capacitor 104 disposed on one side of the mounting circuit board 9. The charge amplifier 102 is electrically connected to the piezoelectric film 8, and the signal acquisition unit 10 is electrically connected to the signal processing control unit 11. The piezoelectric film 8 senses the pressure P and generates a small charge Q proportional to it. The charge amplifier 102 uses the virtual ground principle to forcibly collect all the charges Q and converts them into a proportional voltage V1 = -Q / Cf through the feedback capacitor 103. The filter component filters out the high-frequency noise in V1 and outputs a cleaner voltage V2. The voltage follower 101 receives V2 with a high input impedance and outputs the exact same V3 with a low output impedance, ensuring that the signal is not distorted or attenuated when it is transmitted to the signal processing control unit 11.

[0019] Reference Figure 7As shown, the signal processing control unit 11 includes a voltage reference chip 111, an operational amplifier 112, a voltage-controlled amplifier 113, a voltage-to-current converter chip 114, an MCU control chip 115, an analog-to-digital converter 116, and a feedback diode 117. The signal processing control unit 11 is electrically connected to the buffer assembly 19 and the feedback unit 12. The operational amplifier 112 amplifies, filters, impedance-matches, and levels the signal, amplifying the piezoelectric signal (μV-mV level) to the V level. The voltage reference chip 111 provides a stable and accurate reference voltage, providing a stable Vref for the ADC and determining the conversion accuracy. The voltage-controlled amplifier 113 adjusts the signal gain according to the control voltage, and the gain is digitally controlled by the MCU. The analog-to-digital converter 116 converts the analog voltage into a digital value. The MCU control chip is the "brain" of the system, performing signal processing, decision-making, and control, controlling the overall workflow. The voltage-to-current converter chip 114 accurately converts the control voltage into coil current. This complete system realizes a closed loop from minute pressure to precise magnetic field control, while simultaneously controlling the sealing assembly 20.

[0020] Reference Figure 7 As shown, the feedback unit 12 includes a linear regulator 121, an isolated power supply module 122, a gate driver 123, and a power MOSFET 124. The feedback unit 12 is electrically connected to the sealing assembly 20. The isolated power supply module 122 converts the input main power supply into an electrically independent multi-output power supply through isolation components such as a high-frequency transformer or capacitor. There is no direct electrical connection between the output side (secondary) and the input side (primary), only magnetic or electric field coupling. The high-current switching of the power section will generate huge voltage spikes and noise on its "ground wire". If the control section and the power section share a common ground, this noise will directly interfere with sensitive analog signals (such as piezoelectric signals), causing system instability or inaccurate measurements. The isolated power supply module 122 provides the two with independent "grounds". Noise cannot propagate through the ground wire. The linear regulator 121 uses a transistor as a variable resistor and, through a feedback loop, linearly reduces and stabilizes the input voltage (e.g., 9V from one of the outputs of an isolated power supply) to a precise voltage value. The linear regulator 121 can greatly suppress these ripples, providing "clean" DC power to devices sensitive to power supply noise, such as operational amplifiers, ADCs, and MCUs, ensuring the accuracy of signal conditioning. The gate driver 123 is responsible for converting the control signal output by the MCU or op-amp, which is usually 0-3.3V or 0-5V, into a higher level (e.g., +10V to +15V for full conduction, 0V or negative voltage for full turn-off) of the power MOSFET. The driver performs this voltage conversion.

[0021] Reference Figure 8As shown, the sealing assembly 20 includes a dielectric elastic ring 201. The dielectric elastic ring 201 has fitting grooves 202 on both its inner and outer sides, and flexible electrodes 203 are disposed within each fitting groove 202. When a high DC voltage (typically several kilovolts) is applied between the upper and lower flexible electrodes 203, since the dielectric elastic ring 201 is an insulator, charges cannot pass through. Therefore, positive charges accumulate on the upper electrode, and negative charges accumulate on the lower electrode. Opposite charges attract each other, thus generating a strong electrostatic attraction between the upper and lower flexible electrodes 203. This force acts uniformly over the entire area of ​​the dielectric elastic ring 201. This electrostatic attraction is like two plates being squeezed together by an invisible hand, thereby improving the sealing effect of the dielectric elastic ring 201 between the piston rod 4 and the cylinder head 3.

[0022] Reference Figure 6 As shown, the buffer assembly 19 includes a movable groove 17 formed within the piston 5. A push plate 191 is slidably disposed within the movable groove 17. Connecting rods 192 are connected to both sides of the push plate 191, and a cone 193 is connected to one end of each connecting rod 192. Multiple sets of oil perforations 194 are formed on one side of the push plate 191. When the push plate 191 moves within the movable groove 17, the magnetorheological fluid 18 can flow through the oil perforations 194, thereby generating resistance. An inner sealing ring 195 is provided on the surface of the push plate 191. A fitting groove 196 is formed on one side of the piston 5 corresponding to the cone 193. A second sealing ring 197 is provided inside the piston 5. The second sealing ring 197 ensures the sealing effect between the connecting rod 192 and the piston 5. The movable groove 17 is filled with magnetorheological fluid 18. When the piston 5 moves back and forth within the cylinder 1, the hydraulic oil can simultaneously push the cone 193, thereby causing the push plate 191 to move within the movable groove 17. The piston 5 slides within the cylinder 1 until the push plate 191 moves to the other end of the movable groove 17, causing the cone 193 and push plate 191 at the other end to be fully pushed out. As the piston 5 is about to move to the other end of the cylinder 1, the pushed cone 193 will press against one side of the piezoelectric film 8, thereby pushing the push plate 191 in the opposite direction. At the same time, the electromagnetic coil 14 is energized, which makes the magnetorheological fluid 18 "viscous", increasing the resistance of the push plate 191 sliding in the movable groove 17, thus playing a buffering role. At the same time, when the cone 193 presses against the piezoelectric film 8, the greater the impact force, the greater the charge generated by the piezoelectric film 8. Through the monitoring of the signal acquisition unit 10 and the signal processing control unit 11, the current input to the electromagnetic coil 14 is increased, the magnetic field strength generated by the electromagnetic coil 14 is increased, and the "viscosity" of the magnetorheological fluid 18 is increased, thereby increasing the buffering effect of the buffer component 19.

[0023] Reference Figure 5As shown, the power connection assembly 15 includes a mounting groove 151 on one side of the piston 5. A compression spring 152 is provided inside the mounting groove 151. A grounding seat 153 is provided at one end of the compression spring 152. A grounding ball 154 is rotatably mounted inside the grounding seat 153. A limit seat 155 is provided at the top of the mounting groove 151. A through hole is provided at the top of the limit seat 155 corresponding to the grounding ball 154. A wire 156 is provided at the bottom of the grounding seat 153. The wire 156 is electrically connected to the electromagnetic coil 14. A sealing sleeve 16 is provided on the surface of the piston 5 corresponding to the electromagnetic coil 14, and both ends are... A sealing ring 13 is fitted on one side of the inner wall of the cylinder 1, corresponding to the electric ball 154, and multiple sets of conductive strips 22 are provided. One side of the electric ball 154 has a through hole and is attached to the conductive strip 22. The compression spring 152 can push the grounding seat 153, so that the electric ball 154 can always be kept in contact with the conductive strip 22. The current is transmitted to the electromagnetic coil 14 through the grounding seat 153 and the wire 156. When the piston 5 moves, the energizing effect of the electromagnetic coil 14 can be guaranteed. At the same time, the pure hydraulic oil in the cylinder 1 has an insulating effect and will not affect the use of this structure.

[0024] Reference Figure 7 As shown, an oil passage pipe 71 is provided on one side of the support shell 7. Through the setting of the oil passage pipe 71, the oil passages set in the cylinder bottom 2 and cylinder head 3 can be connected to the cylinder body 1 without affecting the basic use effect of the hydraulic cylinder.

[0025] In use, the piston 5 is pushed by hydraulic oil, moving within the cylinder 1. As the piston 5 moves, the buffer assembly 19 further enhances the buffering effect. Simultaneously, the energizing assembly 15 ensures the energization of the electromagnetic coil 14. When the piston rod 4 moves rapidly (under heavy load), the piston 5 drives the buffer assembly 19 to impact the piezoelectric film 8, generating a large charge. This charge is then monitored and converted by the signal acquisition unit 10, signal processing control unit 11, and protection unit 12, resulting in a control signal that increases the viscosity of the magnetorheological fluid 18 within the buffer assembly 19, thereby improving the buffering effect. The damping effect can be adjusted in real-time based on the monitored impact of the piezoelectric film 8. Furthermore, the internal sealing assembly 20 ensures a proper seal between the piston rod 4 and the cylinder head 3, and the sealing effect of the sealing assembly 20 can be enhanced by controlling the current.

[0026] 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.

[0027] 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 hydraulic cylinder buffer sealing structure applicable to multiple working conditions, comprising a cylinder body (1), characterized in that: The cylinder body (1) is connected to a cylinder head (3) at the front end and a cylinder bottom (2) at the rear end. A piston rod (4) is provided inside the cylinder body (1). A piston (5) is connected to one end of the piston rod (4). A reinforcing member (6) is provided between the piston (5) and the piston rod (4). Support shells (7) are provided at both ends of the inner side of the cylinder body (1). A piezoelectric film (8) is provided on one side of the support shell (7). A mounting circuit board (9) is provided inside the support shell (7). A signal acquisition unit (10), a signal processing control unit (11), and a feedback unit (12) are provided on one side of the mounting circuit board (9). An electromagnetic coil (14) is connected to the outside of the piston (5). A power connection component (15) is connected to one side of the electromagnetic coil (14). Multiple sets of buffer components (19) are provided inside the piston (5). A sealing component (20) is provided inside the cylinder head (3). A connecting ring (21) is provided at the ends of the cylinder bottom (2) and the piston rod (4) that are far apart from each other.

2. The hydraulic cylinder buffer sealing structure applicable to multiple working conditions according to claim 1, characterized in that: The signal acquisition unit (10) includes a voltage follower chip (101), a charge amplifier (102), a filter component (103) and a feedback capacitor (104) disposed on one side of the mounting circuit board (9). The charge amplifier (102) is electrically connected to the piezoelectric film (8), and the signal acquisition unit (10) is electrically connected to the signal processing control unit (11).

3. The hydraulic cylinder buffer sealing structure applicable to multiple working conditions according to claim 2, characterized in that: The signal processing control unit (11) includes a voltage reference chip (111), an operational amplifier (112), a voltage-controlled amplifier (113), a voltage-to-current converter chip (114), an MCU control chip (115), an analog-to-digital converter (116), and a feedback diode (117). The signal processing control unit (11) is electrically connected to the buffer component (19) and the feedback unit (12).

4. The hydraulic cylinder buffer sealing structure applicable to multiple working conditions according to claim 3, characterized in that: The feedback unit (12) includes a linear regulator (121), an isolated power supply module (122), a gate driver (123), and a power MOSFET (124), and the feedback unit (12) is electrically connected to the sealing assembly (20).

5. A hydraulic cylinder buffer sealing structure applicable to multiple working conditions according to claim 4, characterized in that: The sealing assembly (20) includes a dielectric elastic ring (201), and both the inner and outer sides of the dielectric elastic ring (201) are provided with fitting grooves (202), and each fitting groove (202) is provided with a flexible electrode (203).

6. A hydraulic cylinder buffer sealing structure applicable to multiple working conditions according to claim 5, characterized in that: The buffer assembly (19) includes a movable groove (17) opened in the piston (5), a push plate (191) is slidably arranged in the movable groove (17), a connecting rod (192) is connected to both sides of the push plate (191), a cone head (193) is connected to one end of the connecting rod (192), a plurality of oil-permeable holes (194) are opened on one side of the push plate (191), an inner sealing ring (195) is provided on the surface of the push plate (191), a fitting groove (196) is opened on one side of the piston (5) corresponding to the cone head (193), a second sealing ring (197) is provided on the inner side of the piston (5), and a magnetorheological fluid (18) is filled in the movable groove (17).

7. A hydraulic cylinder buffer sealing structure applicable to multiple working conditions according to claim 1, characterized in that: The power connection assembly (15) includes a mounting groove (151) opened on one side of the piston (5), a compression spring (152) is provided inside the mounting groove (151), a grounding seat (153) is provided at one end of the compression spring (152), a power connection ball (154) is rotatably provided inside the grounding seat (153), and a limit seat (155) is provided at the top of the mounting groove (151).

8. A hydraulic cylinder buffer sealing structure applicable to multiple working conditions according to claim 7, characterized in that: The top of the limiting seat (155) is provided with a through hole corresponding to the electric ball (154). The bottom of the grounding seat (153) is provided with a wire (156). The wire (156) is electrically connected to the electromagnetic coil (14). The surface of the piston (5) is provided with a sealing sleeve (16) corresponding to the electromagnetic coil (14), and sealing rings (13) are provided at both ends. One side of the inner wall of the cylinder (1) is provided with multiple sets of conductive strips (22) corresponding to the electric ball (154). The electric ball (154) has a through hole on one side and is attached to the conductive strip (22).

9. A hydraulic cylinder buffer sealing structure applicable to multiple working conditions according to claim 1, characterized in that: An oil permeable pipe (71) is provided on one side of the support shell (7).

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