CN114876911A - Three-stage synchronous telescopic hydraulic oil cylinder - Google Patents
Three-stage synchronous telescopic hydraulic oil cylinder Download PDFInfo
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- CN114876911A CN114876911A CN202210299039.2A CN202210299039A CN114876911A CN 114876911 A CN114876911 A CN 114876911A CN 202210299039 A CN202210299039 A CN 202210299039A CN 114876911 A CN114876911 A CN 114876911A
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B15/00—Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
- F15B15/08—Characterised by the construction of the motor unit
- F15B15/14—Characterised by the construction of the motor unit of the straight-cylinder type
- F15B15/16—Characterised by the construction of the motor unit of the straight-cylinder type of the telescopic type
- F15B15/165—Characterised by the construction of the motor unit of the straight-cylinder type of the telescopic type with synchronisation of sections
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Abstract
The invention discloses a three-stage synchronous telescopic hydraulic oil cylinder which comprises a cylinder barrel, a cylinder bottom, a primary piston cylinder barrel, a secondary piston cylinder barrel, a central piston rod, a primary guide sleeve, a secondary guide sleeve and a central guide sleeve, wherein pistons are arranged at the rear ends of the primary piston cylinder barrel, the secondary piston cylinder barrel and the central piston rod; the cylinder bottom is internally provided with a cavity extending oil port and a cavity contracting oil port, the rear ends of the piston cylinder barrels of all stages are fixedly connected with the respective cylinder bottom, the center of the oil cylinder is internally provided with three sleeved oil through pipes, the front of each piston is provided with an oil through hole for communicating the inner cavity of the piston with the excircle, and the center oil through pipe is connected with the cavity contracting oil port; the cylinder bottom of each stage of piston cylinder barrel is internally provided with an extending cavity oil way and a one-way valve; the telescopic oil ports are all arranged on the cylinder bottom, so that the reciprocating movement of the connecting oil pipe can be avoided, the installation of a pipeline is simplified, the synchronous telescopic of piston rods at all levels is realized, and the use is convenient.
Description
Technical Field
The invention relates to a three-stage hydraulic oil cylinder, in particular to a three-stage synchronous telescopic hydraulic oil cylinder.
Background
An oil port of an extending cavity of a commonly used three-stage telescopic hydraulic oil cylinder is arranged on the outermost cylinder bottom, and an oil port of a contracting cavity is arranged on a central piston rod; when the cylinder barrel is fixed and the piston rod stretches, an oil pipe connected with an oil port of the contraction cavity on the piston rod can move back and forth, so that the installation of a pipeline is not facilitated, synchronous stretching is difficult to realize, and inconvenience is brought to use.
Disclosure of Invention
The invention aims to overcome the defects in the prior art, and provides a three-stage synchronous telescopic hydraulic oil cylinder, wherein telescopic oil ports of the three-stage synchronous telescopic hydraulic oil cylinder are arranged on a cylinder bottom, so that the reciprocating movement of a connecting oil pipe can be avoided, the installation of a pipeline is simplified, the synchronous telescopic of piston rods at all stages is realized, and the convenience is brought to the use.
In order to achieve the purpose, the three-stage synchronous telescopic hydraulic oil cylinder comprises a cylinder barrel, a cylinder bottom, a primary piston cylinder barrel, a secondary piston cylinder barrel, a central piston rod, a primary guide sleeve, a secondary guide sleeve and a central guide sleeve, wherein pistons are arranged at the rear ends of the primary piston cylinder barrel, the secondary piston cylinder barrel and the central piston rod; the method is characterized in that: a cavity extending oil port and a cavity contracting oil port are arranged in the cylinder bottom, a first-stage cylinder bottom is fixedly connected in the rear end of a first-stage piston cylinder barrel, a second-stage cylinder bottom is fixedly connected in the rear end of a second-stage piston cylinder barrel, a through oil pipe is fixedly connected with the cylinder bottom, a first-stage through oil pipe is fixedly connected with the first-stage cylinder bottom, a second-stage through oil pipe is fixedly connected with the second-stage cylinder bottom, a blind hole is arranged in the rear end of the central piston rod, the through oil pipe penetrates through the first-stage cylinder bottom, the front end of the through oil pipe is arranged in the first-stage through oil pipe, the first-stage through oil pipe penetrates through the second-stage cylinder bottom, the front end of the through oil pipe is arranged in the blind hole, the central piston rod is provided with an oil passing hole which communicates the blind hole with an excircle in front of the piston, and the through oil pipe is connected with the cavity contracting oil port; the primary cylinder bottom is internally provided with a primary extending cavity oil way communicated with the front end surface and the rear end surface of the primary cylinder bottom, the primary extending cavity oil way is internally provided with a one-way valve, and the primary cylinder bottom and the primary piston cylinder barrel are provided with a primary oil passing hole communicated with the inner cavity and the excircle of the primary cylinder bottom in front of the piston of the primary cylinder bottom; the second-stage cylinder bottom is internally provided with a second-stage cavity extending oil way communicated with the front end surface and the rear end surface of the second-stage cylinder bottom, the second-stage cavity extending oil way is internally provided with a one-way valve, and the second-stage cylinder bottom and the second-stage piston cylinder barrel are provided with a second-stage oil passing hole communicated with the inner cavity and the excircle of the second-stage cylinder bottom and the piston in front of the piston.
When the hydraulic oil cylinder is used and needs to extend, an oil inlet of an oil port of the extending cavity on the cylinder bottom is used, hydraulic oil pushes the two one-way valves to enter a contracting cavity between the cylinder barrel and the first-stage piston cylinder barrel and a contracting cavity between the first-stage piston cylinder barrel and the second-stage piston cylinder barrel in sequence, and when the two contracting cavities are filled with the hydraulic oil, back cavities of the two one-way valves generate loads to close the two one-way valves; at the moment, the first-stage cylinder bottom and the piston of the first-stage piston cylinder barrel continue to bear oil pressure, the first-stage piston cylinder barrel extends out, the piston moves forwards, and meanwhile, oil in a contraction cavity between the cylinder barrel and the first-stage piston cylinder barrel is extruded into an inner cavity of the first-stage piston cylinder barrel in front of the first-stage cylinder bottom, so that the second-stage piston cylinder barrel extends out, and meanwhile, oil in the contraction cavity between the first-stage piston cylinder barrel and the second-stage piston cylinder barrel is extruded into an inner cavity of the second-stage piston cylinder barrel in front of the second-stage cylinder bottom, so that a central piston rod extends out, and simultaneous action of three-stage piston rods is realized; when the piston is retracted, oil is fed into an oil port of the retraction cavity, hydraulic oil enters the retraction cavity in front of the piston of the central piston rod through the oil through pipe, the primary oil through pipe, the secondary oil through pipe, the blind hole of the central piston rod and the oil through hole, and the central piston rod is retracted; meanwhile, the two check valves are closed under the action of hydraulic oil, oil in the inner cavity of the second-stage piston cylinder barrel and the inner cavity of the first-stage piston cylinder barrel respectively enters the contraction cavity on the outer side of the two check valves, the second-stage piston cylinder barrel and the first-stage piston cylinder barrel simultaneously retract, and the hydraulic oil in front of the cylinder bottom returns to the oil tank through the oil port of the expansion cavity; the invention can realize the simultaneous action of the extension and the retraction of the three-stage piston rod, and the extension oil ports are all arranged on the cylinder bottom, thereby avoiding the back-and-forth movement of the connecting oil pipe, simplifying the installation of the pipeline and bringing convenience to the use;
as a further improvement of the invention, the cross-sectional area of a contraction cavity between the cylinder barrel and the primary piston cylinder barrel is equal to the cross-sectional area of an inner cavity of the primary piston cylinder barrel in front of the primary cylinder bottom; the cross sectional area of a contraction cavity between the first-stage piston cylinder barrel and the second-stage piston cylinder barrel is equal to the cross sectional area of an inner cavity of the second-stage piston cylinder barrel in front of the bottom of the second-stage cylinder; synchronous extension and retraction of the three-stage piston rod can be realized;
as a further improvement of the invention, the primary guide sleeve and the secondary guide sleeve are both provided with vent holes, and plugs are arranged in the vent holes; when the piston cylinder is assembled, air in the two shrinkage cavities can be conveniently discharged, vacuum is realized, and the normal telescopic motion of the two-stage piston cylinder is ensured;
as a further improvement of the invention, a sealing ring is arranged in the first-stage cylinder bottom outside the oil pipe, a sealing ring is arranged in the second-stage cylinder bottom outside the first-stage oil pipe, and a sealing ring is arranged in the piston of the central piston rod outside the second-stage oil pipe; the internal sealing performance of the oil cylinder can be improved;
in summary, the telescopic oil ports of the invention are all arranged on the cylinder bottom, which can avoid the back-and-forth movement of the connecting oil pipe, simplify the installation of the pipeline, realize the synchronous telescopic of all stages of piston rods and bring convenience to the use.
Drawings
FIG. 1 is a front view of an embodiment of the present invention.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings.
As shown in fig. 1, the three-stage synchronous telescopic hydraulic cylinder of this embodiment includes a cylinder barrel 1, a cylinder bottom 2, a first-stage piston cylinder barrel 3, a second-stage piston cylinder barrel 4, a central piston rod 5, a first-stage guide sleeve 6, a second-stage guide sleeve 7, and a central guide sleeve 8, wherein the first-stage guide sleeve 5 and the second-stage guide sleeve 6 are respectively provided with a vent hole 15 or 16, and a plug 17 or 18 is respectively provided in each of the two vent holes through a thread; the rear ends of the primary piston cylinder 3, the secondary piston cylinder 4 and the central piston rod 5 are respectively provided with a piston 9, 10 or 11; a cavity extending oil port 12 and a cavity contracting oil port 13 are arranged in the cylinder bottom 2, a first-stage cylinder bottom 19 is fixedly connected in the rear end of a first-stage piston cylinder barrel 3 through threads, a second-stage cylinder bottom 20 is fixedly connected in the rear end of a second-stage piston cylinder barrel 4 through threads, an oil through pipe 21 is fixedly connected in the cylinder bottom 2 in a welding manner, a first-stage oil through pipe 22 is fixedly connected in the first-stage cylinder bottom 19, a second-stage oil through pipe 23 is fixedly connected in the second-stage cylinder bottom 20, a blind hole 24 is arranged in the rear end of the central piston rod 5, the oil through pipe 21 penetrates through the first-stage cylinder bottom 10, the front end of the oil through pipe is arranged in the first-stage oil through pipe 22, a sealing ring 25 is arranged in the first-stage cylinder bottom 19 outside the oil through pipe 21, the first-stage oil through pipe 22 penetrates through the second-stage cylinder bottom 20, the front end of the first-stage oil through pipe 23 is arranged in the second-stage oil through pipe 23, a sealing ring 26 is arranged in the second-stage cylinder bottom 20 outside the first-stage oil through pipe 22, the piston rod 23 penetrates through piston 11 of the central piston rod 5, the front end of the blind hole 24, an oil pipe 27 is arranged in the piston 11 outside the second-stage oil pipe 23, the center piston rod 5 is provided with an oil passing hole 28 which is communicated with the blind hole 24 and the excircle in front of the piston 11, and the oil pipe 21 is connected with the cavity contracting oil port 13; a primary cavity extending oil way 29 communicated with the front end face and the rear end face of the primary cylinder bottom 19 is arranged in the primary cylinder bottom 19, a one-way valve 30 is arranged in the primary cavity extending oil way 29, and a primary oil passing hole 31 communicated with the inner cavity and the excircle of the primary cylinder bottom 19 and the primary piston cylinder 3 is arranged in front of the piston 9; a secondary cavity extending oil way 32 communicated with the front end face and the rear end face of the secondary cylinder bottom 20 is arranged in the secondary cylinder bottom, a one-way valve 33 is arranged in the secondary cavity extending oil way 32, and a secondary oil passing hole 34 communicated with the inner cavity and the excircle of the secondary cylinder bottom 20 and the secondary piston cylinder barrel 4 is arranged in front of the piston 10; the cross-sectional area of the contraction cavity 35 between the cylinder barrel 1 and the first-stage piston cylinder barrel 3 is equal to the cross-sectional area of the inner cavity of the first-stage piston cylinder barrel 3 in front of the first-stage cylinder bottom 19; the cross-sectional area of the contraction cavity 36 between the first-stage piston cylinder barrel 3 and the second-stage piston cylinder barrel 4 is equal to the cross-sectional area of the inner cavity of the second-stage piston cylinder barrel 4 in front of the second-stage cylinder bottom 20.
When the hydraulic oil sealing device is used and needs to extend, an oil inlet is formed in an extending cavity oil port 12 in the cylinder bottom 2, hydraulic oil enters a first-stage cylinder bottom 19 and a cavity behind a piston 9, two check valves 30 and 33 are pushed open in sequence and enter a contracting cavity 35 between a cylinder barrel 1 and a first-stage piston cylinder barrel 3 and a contracting cavity 36 between the first-stage piston cylinder barrel 3 and a second-stage piston cylinder barrel 4 through a first-stage oil passing hole 31 and a second-stage oil passing hole 34, when the two contracting cavities are filled with the hydraulic oil, load is generated in back cavities of the two check valves 30 and 33, the pressure bearing area of the back cavities of the two valve cores is larger than the area of an oil sealing surface, the two check valves 30 and 33 are closed, and the oil is locked in the two contracting cavities 35 and 36; at the moment, the first-stage cylinder bottom 19 of the first-stage piston cylinder barrel 3 and the piston 9 continue to bear oil pressure, the first-stage piston cylinder barrel 3 extends, the piston 9 moves forwards, oil in a contraction cavity 35 between the cylinder barrel 1 and the first-stage piston cylinder barrel 3 is extruded into an inner cavity of the first-stage piston cylinder barrel 3 in front of the first-stage cylinder bottom 19 through the first-stage oil through hole 31, the second-stage piston cylinder barrel 4 extends, oil in a contraction cavity 36 between the first-stage piston cylinder barrel 3 and the second-stage piston cylinder barrel 4 is extruded into an inner cavity of the second-stage piston cylinder barrel 4 in front of the second-stage cylinder bottom 20 through the second-stage oil through hole 34, the central piston rod 5 extends out, and simultaneous extension of a three-stage piston rod is achieved, and the cross-sectional area of the contraction cavity 35 between the cylinder barrel 1 and the first-stage piston cylinder barrel 3 is equal to the cross-sectional area of the inner cavity of the first-stage piston cylinder barrel 3 in front of the first-stage cylinder bottom 19; the cross section area of a contraction cavity 36 between the first-stage piston cylinder barrel 3 and the second-stage piston cylinder barrel 4 is equal to the cross section area of an inner cavity of the second-stage piston cylinder barrel 4 in front of the second-stage cylinder bottom 20, and the extending distances of the three-stage piston rods are also equal, so that synchronous extending is realized; hydraulic oil in the second-stage piston cylinder 4 in front of the piston 11 returns to the oil tank through the oil passing hole 28, the blind hole 24, the second-stage oil through pipe 23, the first-stage oil through pipe 22, the oil through pipe 21 and the cavity contracting oil port 13; when retracting, the oil inlet 13 of the cavity is arranged, hydraulic oil enters the cavity in front of the piston 11 of the central piston rod 5 through the oil pipe 21, the first-stage oil pipe 22, the second-stage oil pipe 23, the blind hole 24 and the oil passing hole 28, and the central piston rod 5 retracts; meanwhile, the two check valves 30 and 33 are closed under the action of hydraulic oil, oil in the inner cavity of the secondary piston cylinder 4 and the inner cavity of the primary piston cylinder 3 respectively enters the contraction cavities 36 and 35 on the outer sides of the two check valves, the secondary piston cylinder 4 and the primary piston cylinder 3 synchronously retract at the same time, and the hydraulic oil in front of the cylinder bottom 2 returns to the oil tank through the cavity extending oil port 12; the synchronous action of the expansion of the three-stage piston rod can be realized, and the expansion oil ports are all arranged on the cylinder bottom 2, so that the reciprocating movement of a connecting oil pipe can be avoided, the installation of a pipeline is simplified, and the use is convenient; during assembly, air in the two shrinkage cavities 35 and 36 can be conveniently exhausted through the vent holes 15 and 16, vacuum is realized, and the normal telescopic motion of the two-stage piston cylinder barrels 3 and 4 is ensured; the sealing rings 25, 26 and 27 can improve the internal sealing performance of the oil cylinder;
the invention is not limited to the above-described embodiments and "fixedly connected" is to be understood in a broad sense, for example as a fixedly welded connection.
Claims (4)
1. A three-stage synchronous telescopic hydraulic oil cylinder comprises a cylinder barrel, a cylinder bottom, a primary piston cylinder barrel, a secondary piston cylinder barrel, a central piston rod, a primary guide sleeve, a secondary guide sleeve and a central guide sleeve, wherein pistons are arranged at the rear ends of the primary piston cylinder barrel, the secondary piston cylinder barrel and the central piston rod; the method is characterized in that: the cylinder bottom is internally provided with a cavity extending oil port and a cavity retracting oil port, the rear end of the first-stage piston cylinder barrel is fixedly connected with a first-stage cylinder bottom, the rear end of the second-stage piston cylinder barrel is fixedly connected with a second-stage cylinder bottom, the cylinder bottom is fixedly connected with a through oil pipe, the first-stage cylinder bottom is fixedly connected with a first-stage through oil pipe, the second-stage cylinder bottom is fixedly connected with a second-stage through oil pipe, the rear end of the central piston rod is internally provided with a blind hole, the through oil pipe penetrates through the first-stage cylinder bottom, the front end of the through oil pipe is arranged in the first-stage through oil pipe, the first-stage through oil pipe penetrates through the second-stage cylinder bottom, the front end of the through oil pipe is arranged in the blind hole, the central piston rod is provided with an oil passing hole which is communicated with an excircle in front of the piston, and the through oil pipe is connected with the cavity retracting oil port; the primary cylinder bottom is internally provided with a primary extending cavity oil way communicated with the front end surface and the rear end surface of the primary cylinder bottom, the primary extending cavity oil way is internally provided with a one-way valve, and the primary cylinder bottom and the primary piston cylinder barrel are provided with a primary oil passing hole communicated with the inner cavity and the excircle of the primary cylinder bottom in front of the piston of the primary cylinder bottom; the second-stage cylinder bottom is internally provided with a second-stage cavity extending oil way communicated with the front end surface and the rear end surface of the second-stage cylinder bottom, the second-stage cavity extending oil way is internally provided with a one-way valve, and the second-stage cylinder bottom and the second-stage piston cylinder barrel are provided with a second-stage oil passing hole communicated with the inner cavity and the excircle of the second-stage cylinder bottom and the piston in front of the piston.
2. The three-stage synchronous telescopic hydraulic oil cylinder as claimed in claim 1, wherein: the cross sectional area of a contraction cavity between the cylinder barrel and the primary piston cylinder barrel is equal to the cross sectional area of an inner cavity of the primary piston cylinder barrel in front of the primary cylinder bottom; the cross-sectional area of the contraction cavity between the first-stage piston cylinder barrel and the second-stage piston cylinder barrel is equal to the cross-sectional area of the inner cavity of the second-stage piston cylinder barrel in front of the second-stage cylinder bottom.
3. The three-stage synchronous telescopic hydraulic oil cylinder as claimed in claim 1 or 2, characterized in that: the first-stage guide sleeve and the second-stage guide sleeve are provided with vent holes, and plugs are arranged in the vent holes.
4. The three-stage synchronous telescopic hydraulic oil cylinder as claimed in claim 3, characterized in that: a sealing ring is arranged in the first-stage cylinder bottom outside the oil pipe, a sealing ring is arranged in the second-stage cylinder bottom outside the first-stage oil pipe, and a sealing ring is arranged in the piston of the central piston rod outside the second-stage oil pipe.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210299039.2A CN114876911A (en) | 2022-03-25 | 2022-03-25 | Three-stage synchronous telescopic hydraulic oil cylinder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210299039.2A CN114876911A (en) | 2022-03-25 | 2022-03-25 | Three-stage synchronous telescopic hydraulic oil cylinder |
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| Publication Number | Publication Date |
|---|---|
| CN114876911A true CN114876911A (en) | 2022-08-09 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210299039.2A Pending CN114876911A (en) | 2022-03-25 | 2022-03-25 | Three-stage synchronous telescopic hydraulic oil cylinder |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115539733A (en) * | 2022-09-28 | 2022-12-30 | 华中科技大学 | Multistage telescopic hydraulic oil pipe and motion platform |
| CN117605733A (en) * | 2024-01-22 | 2024-02-27 | 张家口长城液压油缸有限公司 | Multistage telescopic erection hydraulic cylinder with core pipe structure |
-
2022
- 2022-03-25 CN CN202210299039.2A patent/CN114876911A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115539733A (en) * | 2022-09-28 | 2022-12-30 | 华中科技大学 | Multistage telescopic hydraulic oil pipe and motion platform |
| CN117605733A (en) * | 2024-01-22 | 2024-02-27 | 张家口长城液压油缸有限公司 | Multistage telescopic erection hydraulic cylinder with core pipe structure |
| CN117605733B (en) * | 2024-01-22 | 2024-03-19 | 张家口长城液压油缸有限公司 | Multistage telescopic erection hydraulic cylinder with core pipe structure |
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