Hydraulic cylinder buffering device

Abstract

The utility model relates to a hydraulic cylinder buffering device which comprises a cylinder barrel, the upper end and the lower end of the cylinder barrel are fixedly connected with a guide cap and a cylinder cover respectively, a piston is arranged in the cylinder barrel in a sliding mode, the end face, facing the guide cap, of the piston is fixedly connected with a piston rod, the piston rod penetrates through the guide cap and extends to the outside of the cylinder barrel, and an outer protruding plug column is fixedly arranged on the end face, facing the cylinder cover, of the piston. A first oil hole is formed in the end face, away from the piston, of the outwards-protruding plug column, the first oil hole penetrates through the outwards-protruding plug column and extends into the piston, a second oil hole is formed in the end face, facing the cylinder cover, of the piston, the second oil hole is communicated with the first oil hole, and a buffering groove matched with the outwards-protruding plug column is formed in the end face, facing the piston, of the cylinder cover. And an oil injection and discharge hole is inwards formed in the outer wall of the cylinder cover and is communicated with the buffer groove. The buffering device buffers and decelerates the action of the piston, so that the piston is in stable contact with the end cover, and the service life of hydraulic cylinder elements is prolonged.

Description

Technical Field

[0001] This utility model relates to the field of hydraulic cylinder technology, specifically to a hydraulic cylinder buffer device. Background Technology

[0002] A hydraulic cylinder is a hydraulic actuator that converts hydraulic energy into mechanical energy and performs linear reciprocating motion. It generally includes a cylinder barrel, cylinder head, end cap, piston, piston rod fixed to the piston, and sealing structure. Based on the hydraulic pressure applied, it can be divided into single-acting and double-acting hydraulic cylinders. A hydraulic cylinder works by injecting oil into the cylinder barrel, which pushes the piston, causing the piston rod to rise and slowly lift the load. Conversely, by discharging oil, the piston rod descends. During operation, especially during oil discharge, the load exerts downward pressure on the piston rod, accelerating its descent and generating a significant impact load. If the piston directly collides with the end cap under inertial force, it will damage the end cap. Therefore, a buffer device is needed to slow down the piston as it reaches the end of its stroke. Utility Model Content

[0003] This invention addresses the shortcomings of existing technologies by providing a hydraulic cylinder buffer device that buffers and slows down the piston's movement, ensuring smooth contact between the piston and the end cap, thereby improving the service life of the hydraulic cylinder components.

[0004] This utility model is achieved through the following technical solution: a hydraulic cylinder buffer device, including a cylinder barrel, with a guide cap and a cylinder cover fixedly connected to the upper and lower ends of the cylinder barrel respectively. A piston is slidably disposed inside the cylinder barrel. A piston rod is fixedly connected to the end face of the piston facing the guide cap, and the piston rod extends through the guide cap to the outside of the cylinder barrel. An outwardly protruding plug is fixedly disposed on the end face of the piston facing the cylinder cover. A first oil hole is opened on the end face of the outwardly protruding plug away from the piston. The first oil hole passes through the outwardly protruding plug and extends into the piston. A second oil hole is opened on the end face of the piston facing the cylinder cover, and the second oil hole communicates with the first oil hole. A buffer groove adapted to the outwardly protruding plug is opened on the end face of the cylinder cover facing the piston. An oil injection / discharge hole is opened inward on the outer wall of the cylinder cover, and the oil injection / discharge hole communicates with the buffer groove.

[0005] This design involves injecting or draining oil through the injection and drain holes, causing the piston to slide up and down, thus raising or lowering it. During oil draining, the piston's downward pressure further compresses the oil, accelerating its discharge. Before the protruding plunger inserts into the buffer groove, the oil directly enters the groove and exits through the injection and drain holes. As the piston slides downward, the protruding plunger inserts into the buffer groove, sealing it. At this point, the oil cannot directly enter the groove and instead forms a buffer layer between the piston and cylinder head. This buffer layer cushions the piston, slowing its descent and reducing impact, preventing direct and rapid contact between the piston and cylinder head, thereby extending component life. As the piston continues to descend and compress the oil, it slowly flows from the second oil hole into the first, then into the buffer groove and exits through the injection and drain holes, ultimately ensuring smooth contact between the piston and cylinder head.

[0006] As an optimization, the diameter of the first oil hole is smaller than the diameter of the injection and drainage oil holes. This optimization scheme makes the speed at which oil enters the first oil hole less than the speed at which it exits. By slowing down the speed at which oil enters the first oil hole, the oil in the buffer zone is slowly discharged, thereby improving the buffering and deceleration effect on the piston.

[0007] As an optimization, the oil injection / drainage hole is connected to the bottom of the buffer groove. This optimization facilitates the drainage of oil entering the buffer groove.

[0008] As an optimization, a first sealing ring is fixedly attached to the sidewall of the buffer groove, and the inner diameter of the first sealing ring is adapted to the outer diameter of the protruding plug. This optimization scheme improves the sealing performance between the protruding plug and the buffer groove through the first sealing ring.

[0009] As an optimization, a sliding pressure plate is provided within the buffer groove, and a spring is installed between the pressure plate and the bottom of the buffer groove. An oil passage hole is formed on the pressure plate, and the oil passage hole is positioned opposite to the first oil hole. In this optimized design, when the protruding piston is inserted into the buffer groove, it presses against the pressure plate, and the elasticity of the spring further buffers the piston, further improving the buffering effect and ensuring the stability of the piston when it reaches the end of its stroke.

[0010] As an optimization, two sliding grooves are formed on the side wall of the buffer groove, symmetrically distributed along the center line of the buffer groove and extending vertically. Two sliding rods are symmetrically fixed to the outer wall of the pressure plate, and the two sliding rods are respectively inserted into the two sliding grooves and slide along the grooves. In this optimized solution, the pressure plate slides up and down along the sliding grooves of the buffer groove through the sliding rods, realizing the sliding connection of the pressure plate and ensuring the stability of the sliding.

[0011] As an optimization, a rubber washer is fixed to the end face of the guide cap facing the piston. This optimized design allows the rubber washer to contact and buffer the piston when it slides upward to the end of its stroke, thus improving the service life of the guide cap.

[0012] As an optimization, two second oil holes are symmetrically formed along the center on the piston end face. This optimization scheme, by symmetrically setting two second oil holes, ensures that the oil in the cylinder is discharged evenly, and that the piston experiences uniform force when squeezing the oil.

[0013] The beneficial effects of this utility model are: when the piston slides upward to the end of its stroke, it contacts the rubber gasket for cushioning, thereby improving the service life of the guide cap.

[0014] As the piston slides downwards at a relatively high speed, it reaches the end of its stroke. The outward-protruding plunger blocks the buffer groove, preventing oil from directly entering and exiting. The oil briefly remains between the piston and cylinder head, forming a buffer zone. This buffer cushions the piston, slowing its descent and reducing impact force, preventing direct and rapid contact between the piston and cylinder head, thus improving component lifespan. Furthermore, when the outward-protruding plunger inserts into the buffer groove, it presses against the pressure plate. The spring's elasticity further cushions the piston, enhancing the buffering effect and ensuring stability at the end of its stroke. As the piston continues to descend, it compresses the oil, which slowly flows from the second oil hole into the first oil hole and then into the buffer groove, exiting through the injection and drainage holes. With the gradual discharge of the buffer oil, the piston eventually makes smooth contact with the cylinder head. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the piston rod in the rising state of this utility model;

[0016] Figure 2 for Figure 1 Enlarged view of part A;

[0017] Figure 3 This is a schematic diagram of the piston rod in the descending state of this utility model;

[0018] Figure 4 for Figure 3 Enlarged view of part B;

[0019] Figure 5 This is a bottom view of the internal structure of the cylinder.

[0020] Figure 6 Top view of the cylinder head;

[0021] As shown in the figure:

[0022] 1. Cylinder barrel, 2. Guide cap, 3. Cylinder head, 4. Piston, 5. Piston rod, 6. Outer protruding plug, 7. First oil hole, 8. Second oil hole, 9. Buffer groove, 10. Injection and drainage holes, 11. Pressure plate, 12. Spring, 13. Rubber gasket, 14. Slide groove, 15. Slide rod, 16. Oil passage hole, 17. First sealing ring, 18. Second sealing ring, 19. Third sealing ring, 20. Fourth sealing ring, 21. Fifth sealing ring. Detailed Implementation

[0023] To clearly illustrate the technical features of this solution, the following detailed implementation method will be used to describe the solution.

[0024] like Figures 1-6 As shown, a hydraulic cylinder buffer device includes a cylinder 1, with a guide cap 2 and a cylinder cover 3 fixedly connected to the upper and lower ends of the cylinder 1, respectively. A piston 4 is slidably disposed inside the cylinder 1, and a piston rod 5 is fixedly connected to the end face of the piston 4 facing the guide cap 2. The piston rod 5 extends through the guide cap 2 to the outside of the cylinder 1.

[0025] In this embodiment, the guide cap 2 is fixed to the circumferential outer wall inside the cylinder 1 with multiple second sealing rings 18. The guide cap 2 and the inner wall of the cylinder 1 are sealed by the multiple second sealing rings 18 to ensure the sealing between the guide cap and the cylinder.

[0026] Preferably, a rubber washer 13 is fixedly attached to the end face of the guide cap 2 facing the piston 4. When the piston 4 slides upward to the end of its stroke, it contacts the rubber washer 13 for cushioning, thereby improving the service life of the guide cap 2.

[0027] In this embodiment, the cylinder head 3 is fixed to the circumferential outer wall inside the cylinder barrel 1 with multiple third sealing rings 19. The cylinder head 3 and the inner wall of the cylinder barrel 1 are sealed by the multiple third sealing rings 19 to ensure the sealing between the cylinder head and the cylinder barrel.

[0028] In this embodiment, a fourth sealing ring 20 is fixedly connected to the circumferential outer wall of the piston 4. The piston 4 and the inner wall of the cylinder 1 are sealed by the fourth sealing ring 20 to ensure the sealing between the piston and the cylinder.

[0029] In this embodiment, the piston rod 5 is fixedly connected to the center of the piston 4. The guide cap 2 has a through hole at its center that matches the outer diameter of the piston rod 5, through which the piston rod 5 extends to the outside. Multiple fifth sealing rings 21 are fixedly connected to the inner wall of the through hole, and the piston rod 5 is sealed to the through hole by the multiple fifth sealing rings 21, ensuring the sealing between the piston rod and the guide cap.

[0030] The piston 4 is fixedly provided with an outwardly protruding plunger 6 on the end face facing the cylinder head 3. In this embodiment, the outwardly protruding plunger 6 is a cylindrical structure, located at the center of the piston 4 and integrally formed with the piston 4.

[0031] A first oil hole 7 is formed on the end face of the protruding plunger 6 away from the piston 4, extending inward through the protruding plunger 6 and into the piston 4. A second oil hole 8 is formed on the end face of the piston 4 facing the cylinder head 3, and the second oil hole 8 communicates with the first oil hole 7.

[0032] Specifically, the second oil hole 8 is bent and connected to the first oil hole 7 at one end of the piston 4. In this embodiment, two second oil holes 8 are symmetrically arranged along the center on the end face of the piston 4. By symmetrically arranging the two second oil holes 8, the oil can be discharged evenly when the piston 4 squeezes the oil, resulting in uniform force and improved discharge stability.

[0033] The cylinder head 3 has a buffer groove 9 on its end face facing the piston 4, which is adapted to the protruding piston 6. Specifically, the buffer groove 9 is located at the center of the end face of the cylinder head 3, and the buffer groove 9 and the protruding piston 6 are arranged opposite to each other. The inner diameter of the buffer groove 9 is adapted to the outer diameter of the protruding piston 6, so that the protruding piston 6 can close the buffer groove 9 when it is inserted into it.

[0034] Preferably, a first sealing ring 17 is fixedly connected to the side wall of the buffer groove 9, and the inner diameter of the first sealing ring 17 is adapted to the outer diameter of the protruding plug 6. The first sealing ring 17 improves the sealing performance between the protruding plug 6 and the buffer groove 9, preventing oil from seeping in when the protruding plug seals the buffer groove.

[0035] An oil injection / drainage hole 10 is provided on the outer wall of the cylinder head 3, and the oil injection / drainage hole 10 is connected to the buffer groove 9. Oil is injected or discharged through the oil injection / drainage hole 10. In this embodiment, the oil injection / drainage hole 10 is connected to the bottom of the buffer groove 9, which facilitates the complete discharge of oil. Furthermore, the connection between the oil injection / drainage hole 10 and the buffer groove 9 is a flared transition, which facilitates the entry of oil into the oil injection / drainage hole.

[0036] Preferably, the diameter of the first oil hole 7 is smaller than the diameter of the oil injection / discharge hole 10. The speed at which oil enters the first oil hole is less than the speed at which it exits, allowing the oil in the buffer zone to be slowly discharged, thereby improving the buffering and deceleration effect on the piston.

[0037] The buffer groove 9 is equipped with a sliding pressure plate 11. A spring 12 is provided between the pressure plate 11 and the bottom of the buffer groove 9. An oil passage hole 16 is provided on the pressure plate 11, which is opposite to the first oil hole 7. When the protruding piston 6 is inserted into the buffer groove 9, it presses against the pressure plate 11. The elastic action of the spring 12 further buffers the piston 4, further improving the buffering effect and ensuring the stability of the piston when it reaches the end of its stroke.

[0038] Specifically, two sliding grooves 14 are formed on the side wall of the buffer groove 9. The two sliding grooves 14 are symmetrically distributed along the center line of the buffer groove 9 and extend vertically. Two sliding rods 15 are symmetrically fixed to the outer wall of the pressure plate 11. The two sliding rods 15 are respectively inserted into the two sliding grooves 14 and slide along the sliding grooves 14. The pressure plate 11 slides up and down along the sliding grooves 14 of the buffer groove through the sliding rods 15, realizing the sliding setting of the pressure plate and ensuring the stability of the sliding.

[0039] Working principle: When in use, oil is injected through the oil injection hole 10. The oil enters the buffer groove 9, which pushes the piston 4 to slide upward, thereby causing the piston rod 5 to slowly rise and lift the heavy object. When the piston 4 rises to the end of its stroke, it contacts the rubber washer 13. The impact force is reduced by the buffering effect of the rubber washer 13, which improves the service life of the guide cap 2.

[0040] When piston rod 5 needs to descend, oil is discharged through oil inlet / outlet hole 10. At this time, piston rod 5 descends rapidly under the pressure of the weight, causing piston 4 to slide downwards quickly and squeeze the oil. As piston 4 descends, when the protruding plunger 6 inserts into buffer groove 9, it closes buffer groove 9. At this time, oil cannot directly enter buffer groove 9 and be discharged quickly, thus forming buffer oil during a brief stay between piston 4 and cylinder head 3. This buffer oil cushions piston 4, slowing down the descent speed of piston 4, reducing impact force, and preventing piston 4 from directly contacting and colliding with cylinder head 3, thereby improving the service life of cylinder head. At the same time, when the protruding plunger 6 inserts into buffer groove 9, it presses against pressure plate 11. Through the elastic action of spring 12 on pressure plate 11, it further provides a cushioning effect for piston 4, ensuring the stability of piston when it reaches the end of its stroke.

[0041] As the piston 4 continues to descend and compress the oil, the oil slowly enters the first oil hole 7 from the second oil hole 8, and flows from the first oil hole 7 through the oil passage hole 16 into the buffer groove 9 and is discharged through the oil injection and discharge hole 10, finally allowing the piston 4 to make smooth contact with the cylinder head 3.

[0042] Of course, the above description is not limited to the examples above. Technical features of this utility model not described can be implemented by or using existing technology, and will not be repeated here. The above embodiments and drawings are only used to illustrate the technical solution of this utility model and are not intended to limit this utility model. This utility model has been described in detail with reference to preferred embodiments. Those skilled in the art should understand that any changes, modifications, additions or substitutions made by those skilled in the art within the scope of this utility model do not depart from the spirit of this utility model and should also fall within the protection scope of the claims of this utility model.

Claims

1. A hydraulic cylinder buffer device, comprising a cylinder (1), a guide cap (2) and a cylinder cover (3) respectively fixedly connected to the upper and lower ends of the cylinder (1), a piston (4) slidably disposed inside the cylinder (1), a piston rod (5) fixedly connected to the end face of the piston (4) facing the guide cap (2), the piston rod extending through the guide cap to the outside of the cylinder, characterized in that: The piston (4) is fixed with an outwardly protruding plug (6) on the end face facing the cylinder head (3). The outwardly protruding plug (6) is provided with a first oil hole (7) on the end face away from the piston (4). The first oil hole (7) passes through the outwardly protruding plug (6) and extends into the piston (4). The piston (4) is provided with a second oil hole (8) on the end face facing the cylinder head (3). The second oil hole (8) is connected to the first oil hole (7). The cylinder head (3) is provided with a buffer groove (9) adapted to the outwardly protruding plug (6) on the end face facing the piston (4). The cylinder head (3) is provided with an oil injection / drainage hole (10) on the outer wall inward. The oil injection / drainage hole (10) is connected to the buffer groove (9).

2. The hydraulic cylinder buffer device according to claim 1, characterized in that: The diameter of the first oil hole (7) is smaller than the diameter of the oil injection / drainage hole (10).

3. The hydraulic cylinder buffer device according to claim 1, characterized in that: The oil injection / drainage hole (10) is connected to the bottom of the buffer groove (9).

4. The hydraulic cylinder buffer device according to claim 1, characterized in that: A first sealing ring (17) is fixed to the side wall of the buffer groove (9), and the inner diameter of the first sealing ring is adapted to the outer diameter of the protruding plug.

5. The hydraulic cylinder buffer device according to claim 1, characterized in that: The buffer groove (9) is provided with a sliding pressure plate (11), and a spring (12) is provided between the pressure plate (11) and the bottom of the buffer groove (9). An oil passage hole (16) is provided on the pressure plate (11), and the oil passage hole (16) is arranged opposite to the first oil hole (7).

6. The hydraulic cylinder buffer device according to claim 5, characterized in that: Two sliding grooves (14) are provided on the side wall of the buffer groove (9). The two sliding grooves (14) are symmetrically distributed along the center line of the buffer groove (9). The sliding grooves extend vertically. Two sliding rods (15) are symmetrically fixed on the outer wall of the pressure plate (11). The two sliding rods (15) are respectively inserted into the two sliding grooves (14) and slide along the sliding grooves.

7. The hydraulic cylinder buffer device according to claim 1, characterized in that: A rubber gasket (13) is fixed to the end face of the guide cap (2) facing the piston (4).

8. The hydraulic cylinder buffer device according to claim 1, characterized in that: Two second oil holes (8) are symmetrically opened along the center on the end face of the piston (4).

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