Patent Application
20150197972
1. Field of the Invention
The present invention relates to a hydraulic cylinder impact-buffering assembly, and more particularly relates to a hydraulic cylinder impact-buffering assembly that can mitigate the impact phenomenon of the hydraulic cylinder impact-buffering assembly.
2. Description of Related Art
A conventional hydraulic cylinder buffering assembly has an outer cylinder and a piston rod. The outer cylinder is a hollow tube, is used to store hydraulic oil and has an inner diameter. The piston rod is movably connected to the outer cylinder and has an inner end, an outer end and a piston. The inner end of the piston rod is mounted in the outer cylinder. The outer end of the piston rod extends out of the outer cylinder. The piston is securely mounted on the inner end of the piston rod and has an outer diameter. The outer diameter of the piston is smaller than the inner diameter of the outer cylinder. When the piston rod is moved relative to the outer cylinder, the piston is moved with the piston rod relative to the outer cylinder to enable the hydraulic oil to move from one side to another side of the piston. When the hydraulic oil flows across the piston, a hydraulic pressure will be generated and provide a buffering effect to the piston rod.
In addition, the piston has a middle, an outer surface, a mounting recess, an oil ring and multiple guiding holes. The mounting recess is formed around the outer surface of the piston at the middle of the piston. The oil ring is mounted in the mounting recess of the piston and abuts an inner surface of the outer cylinder. The guiding holes are formed through the sides of the piston and communicate with the mounting recess of the piston. Furthermore, the guiding holes that are formed at the sides of the piston have different inner diameters, and this can enable the hydraulic oil to flow across the piston via the guiding holes having different inner diameters to provide different buffering forces to the piston rod when the piston rod is moved relative to the outer cylinder with different movement directions.
Although the conventional hydraulic cylinder buffering assembly can be used on a track to provide a buffering effect to a door via the piston rod, the conventional hydraulic cylinder buffering assembly is only applicable when the piston rod receives a relatively small external force to enable the hydraulic oil to flow smoothly between the guiding holes of different inner diameters. If the piston rod receives a relatively large external force, the hydraulic oil cannot flow across the piston from the guiding holes with small inner diameters to the guiding holes with large inner diameters in a short time, and this will cause an excessive speed difference between the piston rod and the door. Then, the speed of the door is rapidly reduced, thereby causing a strong vibration of the door or impact on the door. That is, when the piston rod receives a relatively large external force, the conventional hydraulic cylinder buffering assembly cannot provide a buffering effect to the piston rod. Therefore, the conventional hydraulic cylinder buffering assembly needs improvement.
To overcome the shortcomings, the present invention provides a hydraulic cylinder impact-buffering assembly to mitigate the aforementioned problems.
The main objective of the present invention is to provide a hydraulic cylinder impact-buffering assembly that can mitigate the impact phenomenon of the hydraulic cylinder impact-buffering assembly.
The hydraulic cylinder impact-buffering assembly in accordance with the present invention has an outer cylinder and a piston rod. The outer cylinder is a hollow tube and has an opening. The piston rod is movably connected to the outer cylinder and has a piston. The piston is securely connected to the piston rod, is movably mounted in the outer cylinder, and has a connecting segment and a flowing segment. The connecting segment is securely connected to the piston rod and has a connecting recess, a ball recess, multiple side leaking holes, a leaking ball and a spring. The flowing segment is formed on and protrudes from the connecting segment and has a mounting recess, an oil ring, a central recess, multiple first guiding holes and multiple second guiding holes.
Other objectives, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.
With reference to
The outer cylinder 10 is a hollow tube and has a distal end, a proximal end, an inner diameter, an internal surface, a connecting head 11, an opening 12 and a sealing block 13. The connecting head 11 is connected to the distal end of the outer cylinder 10. The opening 12 is formed through the proximal end of the outer cylinder 10. The sealing block 13 is mounted in the outer cylinder 10 and adjacent to the opening 12 to seal the opening 12.
The piston rod 20 is movably connected to the outer cylinder 10 and has an inner end, an outer end, an external surface, an outer thread 21 and a piston 30. The inner end of the piston rod 20 is movably mounted in the outer cylinder 10 via the opening 12 and the sealing block 13. The outer thread 21 is formed on the external surface of the piston rod 20 at the inner end of the piston rod 20.
The piston 30 is securely connected to the piston rod 20, is movably mounted in the outer cylinder 10 and has a connecting segment 31 and a flowing segment 32.
The connecting segment 31 is securely connected to the inner end of the piston rod 20 and has a connecting end, a forming end, an external surface, an outer diameter, a connecting recess 311, a ball recess 312, multiple side leaking holes 313, a leaking ball 314 and a spring 315. The connecting recess 311 is axially formed in the connecting end of the connecting segment 31, is mounted around and connected to the inner end of the piston rod 20, and has an internal surface and an inner thread 316. The inner thread 316 is formed on the internal surface of the connecting recess 311 and is screwed with the outer thread 21 of the piston rod 20. The ball recess 312 is axially formed in the forming end of the connecting segment 31 and communicates with the connecting recess 311.
The side leaking holes 313 are radially formed in the external surface of the connecting segment 31 at intervals and communicate with the ball recess 312. The leaking ball 314 is mounted in the ball recess 312 and between the side leaking holes 313. The spring 315 is mounted in the ball recess 312 and abuts the inner end of the piston rod 20 and the leaking ball 314 to enable the leaking ball 314 to locate between the side leaking holes 313.
The flowing segment 32 is formed on and protrudes from the forming end of the connecting segment 31 and has an outer diameter, a forming end, a flowing end, a middle, an external surface, a mounting recess 321, an oil ring 322, a central recess 323, multiple first guiding holes 324 and multiple second guiding holes 325. The outer diameter of the flowing segment 32 is larger than the outer diameter of the connecting segment 31. The forming end of the flowing segment 32 is formed with the forming end of the connecting segment 31. The mounting recess 321 is annularly formed in the external surface of the flowing segment 32 at the middle of the flowing segment 32 to form two flanges 326, 327 beside the mounting recess 321.
The flanges 326, 327 are respectively a first flange 326 and a second flange 327. The first flange 326 is formed on and protrudes from the external surface of the flowing segment 32 and between the mounting recess 321 and the side leaking holes 313 of the connecting segment 31. The second flange 327 is formed on and protrudes from the external surface of the flowing segment 32 and between the mounting recess 321 and the flowing end of the flowing segment 32. Furthermore, with reference to
The oil ring 322 is mounted around the external surface of the flowing segment 32 in the mounting recess 321, abuts the internal surface of the outer cylinder 10 and selectively abuts the first flange 326 and the second flange 327 to enable hydraulic oil that is stored in the outer cylinder 10 to flow across the piston 30. The central recess 323 is axially formed through the forming end and the flowing end of the flowing segment 32, aligns with an axis of the flowing segment 32 and selectively communicates with the side leaking holes 313 when the leaking ball 314 is moved relative to the connecting segment 31. A passage between the central recess 323 of the flowing segment 32 and the side leaking holes 313 of the connecting segment 31 is closed by the leaking ball 314 that is pressed by the spring 315.
The first guiding holes 324 are radially formed through the first flange 326 at intervals, communicate with the mounting recess 321, and each one of the first guiding holes 324 has an inner diameter. The second guiding holes 325 are radially formed through the second flange 327 at intervals, communicate with the mounting recess 321, and each one of the second guiding holes 325 has an inner diameter. The inner diameters of the second guiding holes 325 are larger than the inner diameters of the first guiding holes 324. Additionally, when the hydraulic oil flows in the central recess 323 from the flowing end of the flowing segment 32, as the leaking ball 314 faces the side leaking holes 313, the hydraulic oil will flow out via the side leaking holes 313 without flowing across the leaking ball 314 and this can avoid the noise generated by the vibration of the leaking ball 314.
With reference to
With reference to
With reference to
However, the hydraulic pressure of the hydraulic oil that flows across the piston 30 via the second guiding holes 325, the interval between the second flange 327 and the internal surface of the outer cylinder 10, the mounting recess 321 and the first guiding holes 324 is not sufficient to overcome the pressure of the relatively large external force. The excessive pressure of the relatively large external force will enable the hydraulic oil to push the leaking ball 314 via the central recess 323 to move toward the inner end of the piston rod 20 to compress the spring 315 and to enable the side leaking holes 313 to communicate with the central recess 323. Then, the hydraulic oil that is located at the flowing end of the flowing segment 32 also can flow to the connecting end of the connecting segment 31 via the passage between the central recess 323 and the side leaking holes 313. Therefore, when the piston rod 20 receives a relatively large external force, the hydraulic oil can flow across the piston 30 from the flowing segment 32 to the connecting segment 31 via the second guiding holes 325, the interval between the second flange 327 and the internal surface of the outer cylinder 10, the mounting recess 321 and the first guiding holes 324 and also via the central recess 323 and the side leaking holes 313.
In addition, when the hydraulic pressure of the hydraulic oil is reduced to a certain extent, the compressed spring 315 will push the leaking ball 314 to move backwardly to the original position to close the passage between the central recess 323 and the side leaking holes 313. Consequently, when the piston rod 20 of the hydraulic cylinder impact-buffering assembly in accordance with the present invention receives a large external force, the hydraulic oil can still flow smoothly in the outer cylinder 10 and also can provide a buffering effect to the door via the piston rod 20 to prevent an excessive speed difference between the piston rod 20 and the door, thereby avoiding strong vibrations of the door or impact on the door.
Even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and features of the invention, the disclosure is illustrative only. Changes may be made in the details, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.
