CN113969917B - Multistage hydraulic cylinder - Google Patents
Multistage hydraulic cylinder Download PDFInfo
- Publication number
- CN113969917B CN113969917B CN202111247503.5A CN202111247503A CN113969917B CN 113969917 B CN113969917 B CN 113969917B CN 202111247503 A CN202111247503 A CN 202111247503A CN 113969917 B CN113969917 B CN 113969917B
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- primary
- rod assembly
- groove
- hydraulic cylinder
- oil cavity
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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
- F15B15/1423—Component parts; Constructional details
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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
- F15B15/1423—Component parts; Constructional details
- F15B15/1447—Pistons; Piston to piston rod assemblies
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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
- F15B15/1423—Component parts; Constructional details
- F15B15/1457—Piston rods
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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
- F15B15/149—Fluid interconnections, e.g. fluid connectors, passages
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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
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- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Actuator (AREA)
Abstract
The invention relates to a multistage hydraulic cylinder, which effectively solves the problem that the load capacity of the multistage hydraulic cylinder is weakened along with the extension of a hydraulic rod; the technical scheme includes that the device comprises a cylinder body, a primary rod assembly and a secondary rod assembly, wherein a plurality of groups of annular grooves are formed in the inner wall of the primary rod assembly, the annular grooves are uniformly distributed along the axial direction, each group of annular grooves consists of a primary groove and a secondary groove, the secondary groove is formed in the bottom of the primary groove, a plurality of poppable clamping blocks are uniformly distributed on the circumference of the side wall of the bottom of the secondary rod assembly, in the process that the secondary rod assembly extends outwards, when the clamping blocks are opposite to the annular grooves, the clamping blocks extend outwards under the action of springs to be clamped into the primary grooves, and the clamping blocks can upwards cross the annular grooves; the lower oil cavity is internally provided with a plunger, the lower end of the plunger extends out of the cylinder body, a first communication hole is formed between the upper oil cavity and the lower oil cavity, and a pressure valve is arranged on the first communication hole; the invention can apply the load to all hydraulic rods, reduce the pressure intensity during the pressure maintaining of the hydraulic cylinder and improve the load capacity of the hydraulic cylinder.
Description
Technical Field
The invention relates to the field of hydraulic equipment, in particular to a multistage hydraulic cylinder.
Background
The diameter of the hydraulic rod is smaller and smaller along with the extension of the hydraulic rod of each stage of the current multi-stage hydraulic cylinder, and the effective acting area of hydraulic oil is gradually reduced, for example, after the extension of the second-stage hydraulic rod, the first-stage hydraulic rod is not born with load, the load is completely acted on the hydraulic rods of the later stages, and the number of the hydraulic rods actually born is reduced for one stage when the first-stage hydraulic rod extends out; the reduction of the effective area causes the load capacity of the hydraulic cylinder to be weakened, and under the condition of the same load, the pressure in the cavity is larger during the pressure maintaining period, so that the leakage of the cylinder explosion is easier.
Disclosure of Invention
The invention provides a multistage hydraulic cylinder, which aims to solve the problem that the load capacity of the multistage hydraulic cylinder is weakened along with the extension of a hydraulic rod.
The technical scheme is that the multistage hydraulic cylinder comprises a cylinder body, a primary rod assembly and a secondary rod assembly, wherein the cylinder body is divided into an upper oil cavity and a lower oil cavity, the primary rod assembly is sleeved in the upper oil cavity, the secondary rod assembly is sleeved in the primary rod assembly, a first oil hole and a second oil hole are formed in the upper oil cavity, and a liquid return channel is formed in the primary rod assembly; the inner wall of the primary rod assembly is provided with a plurality of groups of annular grooves, the annular grooves are uniformly distributed along the axial direction, each group of annular grooves consists of a primary groove and a secondary groove, and the secondary groove is arranged at the bottom of the primary groove; the bottom side wall of the secondary rod assembly is provided with a plurality of radial blind holes with circumferentially uniformly distributed, each blind hole is internally provided with a clamping block, a spring is arranged between the clamping block and the bottom of the blind hole, and when the clamping block is opposite to the annular groove in the process of outwards extending the secondary rod assembly, the clamping block outwards extends to be clamped into the primary groove under the action of the spring; the upper side of the primary groove is an arc surface, and the clamping block can upwards pass through the annular groove when the secondary rod assembly stretches out; the plunger is arranged in the lower oil cavity, the lower end of the plunger extends out of the cylinder body, a first communication hole is formed between the upper oil cavity and the lower oil cavity, and a pressure valve is arranged on the first communication hole.
The primary rod assembly consists of a primary piston and a primary ejector rod, the annular groove is formed in the inner wall of the primary ejector rod, the secondary rod assembly consists of a secondary piston and a secondary ejector rod, and the clamping block is arranged on the outer wall of the secondary piston.
The secondary rod assembly is internally provided with an exhaust hole, the upper port of the exhaust hole is positioned at the top of the side wall of the secondary ejection rod, and the lower port of the exhaust hole is communicated with the bottoms of the blind holes.
The axial thickness of the secondary piston is larger than the width of the primary groove.
When the clamping block is clamped in the primary groove, the upper edge of the secondary piston is lower than the upper edge of the primary groove.
A second communication hole is formed between the upper oil cavity and the lower oil cavity, and a switch valve is arranged on the second communication hole.
The lower end of the bottom plunger is provided with a base.
The invention can apply the load to all hydraulic rods, reduce the pressure intensity during the pressure maintaining of the hydraulic cylinder and improve the load capacity of the hydraulic cylinder.
Drawings
Fig. 1 is a front cross-sectional view of the present invention in an initial state.
Fig. 2 is a front cross-sectional view of the present invention with the primary rod fully extended.
Fig. 3 is a front cross-sectional view of the present invention with the secondary rod extended.
Fig. 4 is a front cross-sectional view of the invention with the plunger extended and the cartridge captured in the annular groove.
Fig. 5 is an enlarged view of the position a in fig. 1.
Fig. 6 is an enlarged view of the position B in fig. 1.
Fig. 7 is an enlarged view of position C in fig. 4.
Detailed Description
Specific embodiments of the present invention are further described below with reference to the accompanying drawings.
The hydraulic cylinder comprises a cylinder body 1, a primary rod assembly and a secondary rod assembly, wherein the cylinder body 1 is divided into an upper oil cavity 2 and a lower oil cavity 3, the primary rod assembly is sleeved in the upper oil cavity 2, the secondary rod assembly is sleeved in the primary rod assembly, a first oil hole 4 and a second oil hole 5 are formed in the upper oil cavity 2, a liquid return channel 6 is formed in the primary rod assembly, the first oil hole 4, the second oil hole 5 and the liquid return channel 6 are hydraulic oil channels for controlling ejection and return of a hydraulic rod, and the ejection and return of the hydraulic rod are all the prior art of a multi-stage hydraulic cylinder and are not repeated herein; the inner wall of the primary rod assembly is provided with a plurality of groups of annular grooves 7, the annular grooves 7 are uniformly distributed along the axial direction, each group of annular grooves 7 consists of a primary groove 8 and a secondary groove 9, and the secondary groove 9 is arranged at the bottom of the primary groove 8; the bottom side wall of the secondary rod assembly is provided with a plurality of radial blind holes 10 with circumferentially uniformly distributed, each blind hole 10 is internally provided with a clamping block 11, a spring 12 is arranged between the clamping block 11 and the bottom of the blind hole 10, when the clamping block 11 is opposite to the annular groove 7 in the outward extending process of the secondary rod assembly, the clamping block 11 is outwards extended and clamped into the primary groove 8 under the action of the spring 12, and at the moment, the load of the secondary rod assembly can act on the primary rod assembly through the clamping block 11 and the annular groove 7, so that the primary rod assembly and the secondary rod assembly bear the load; the upper side of the primary groove 8 is an arc surface, and the clamping block 11 can upwards pass through the annular groove 7 when the secondary rod assembly stretches out; the lower oil cavity 3 is internally provided with a plunger 13, the lower end of the plunger 13 extends out of the cylinder body 1, a first communication hole 14 is arranged between the upper oil cavity 2 and the lower oil cavity 3, and a pressure valve 15 is arranged on the first communication hole 14.
The primary rod assembly consists of a primary piston 16 and a primary ejection rod 17, the annular groove 7 is formed in the inner wall of the primary ejection rod 17, the secondary rod assembly consists of a secondary piston 18 and a secondary ejection rod 19, and the clamping block 11 is arranged on the outer wall of the secondary piston 18.
The secondary rod assembly is internally provided with an exhaust hole 20, the upper port of the exhaust hole 20 is positioned at the top of the side wall of the secondary ejection rod 19, and the lower port of the exhaust hole 20 is communicated with the bottoms of the blind holes 10, so that the air pressure balance at the bottom of the clamping block 11 is maintained, and positive pressure or negative pressure resistance is avoided when the clamping block 11 moves.
The axial thickness of the secondary piston 18 is greater than the width of the primary groove 8, so that at least one side of the upper side and the lower side of the primary groove 8 is sealed, and oil leakage from the high-pressure cavity to the low-pressure cavity through the primary groove 8 when the secondary piston 18 passes through the primary groove 8 can be avoided.
When the clamping blocks 11 are clamped in the primary grooves 8, the upper edge of the secondary piston 18 is lower than the upper edge of the primary grooves 8, so that when the secondary rod is retracted, return oil pressure above the secondary piston 18 can enter the primary grooves 8 and act on the tops of all the clamping blocks 11 through the secondary grooves 9, the clamping blocks 11 are pressed into the blind holes 10, and the secondary rod assembly can move back to the position.
A second communication hole 21 is formed between the upper oil cavity 2 and the lower oil cavity 3, a switch valve 22 is arranged on the second communication hole 21, and the upper oil cavity 2 and the lower oil cavity 3 can be actively communicated by opening the switch valve 22.
The lower end of the bottom plunger 13 is provided with a base 23.
The working process of the invention is described in detail below for three common load types:
load type one: the load position is fixed, and the hydraulic cylinder supports the load, for example, the support at the top of a roadway is reinforced; the hydraulic oil is filled in the upper oil cavity 2 from the first oil hole 4, the primary rod assembly extends out firstly, the secondary rod assembly extends out again, and if the primary rod assembly does not extend out completely, the load is propped up, the oil filling is stopped, and the pressure is maintained; if the secondary rod assembly stretches out, when the clamping block 11 on the secondary rod assembly is clamped into one of the primary grooves 8 and the target position is approached at the moment, the switch valve 22 is manually opened and oil continues to be filled, hydraulic oil can act on the plunger 13 at the moment, the plunger 13 stretches out and the secondary rod assembly does not move relative to the primary rod assembly under the same pressure because the acting area of the plunger 13 is larger than the acting area of the secondary piston 18, and the reaction force generated by the stretching out of the plunger 13 pushes the cylinder body 1, the primary rod assembly and the secondary rod assembly to synchronously move upwards until the secondary ejection rod 19 supports the load and reaches the required supporting force, and then the oil filling and pressure maintaining are stopped; in this state, a load acts on the secondary ejector rod 19 and acts on the primary ejector rod 17 via the clamp block 11, so that both the primary piston 16 and the secondary piston 18 bear the load, the effective acting area of the hydraulic oil is the total area of the primary piston 16 and the secondary piston 18, and the required oil pressure is reduced under the same load.
Load type two: the load is constant, and the hydraulic cylinder pushes the load to move to a target position, such as lifting a weight; the operation is the same as the operation of the first load type, the secondary lever assembly is first extended to near the target position, and the plunger 13 is extended again to push the load to the target position and hold the pressure.
Load type three: as the throw increases, the load size continues to increase, such as compressing the material; the hydraulic oil is filled in the oil cavity 2 from the first oil hole 4, the primary rod assembly extends out firstly, the secondary rod assembly extends out again, in the extending process of the secondary rod assembly, the load is continuously increased, the pressure in the upper oil cavity 2 is increased, when the opening threshold value of the pressure valve 15 is reached, the pressure valve 15 is automatically opened, the plunger 13 extends out to push the cylinder body 1 and the primary rod assembly to ascend, at the moment, the secondary rod assembly is motionless, the load is constant until the clamping block 11 is clamped in the primary groove 8, the primary rod assembly pushes the secondary rod assembly to synchronously ascend through the primary groove 8 and the clamping block 11, at the moment, the primary ejection rod 17 and the secondary ejection rod 19 are stressed, the effective acting area of the hydraulic oil is the area of the primary piston 16 and the secondary piston 18, and larger thrust can be provided under the condition that the pressure in the cylinder body 1 is not increased, so that the compression stroke is increased.
During return, hydraulic oil injected from the second oil hole 5 enters the cylinder body 1 and enters the primary rod assembly through the liquid return channel 6 to push the primary rod assembly and the secondary rod assembly to move downwards, when the clamping blocks 11 are clamped in the annular grooves 7, gaps are reserved between the secondary pistons 18 and the upper edges of the primary grooves 8, the hydraulic oil enters the primary grooves 8 through the gaps and acts on the tops of all the clamping blocks 11 through the secondary grooves 9, the clamping blocks 11 are pushed out of the primary grooves 8 to be pressed into the blind holes 10, and the primary rod can continue to move downwards until the primary rod assembly and the secondary rod assembly are completely returned.
When the plunger 13 returns, the on-off valve 22 is opened, and the plunger 13 is pushed back into the lower oil chamber 3.
For three types of loads, the hydraulic cylinder pressure maintaining device can reduce the pressure intensity during the pressure maintaining of the hydraulic cylinder, reduce the risks of cylinder explosion, leakage and hydraulic element damage during the pressure maintaining of the hydraulic cylinder, and can improve the pushing stroke and the maximum pushing force of the hydraulic cylinder to meet the compression operation with higher compression ratio requirements.
Claims (5)
1. The multistage hydraulic cylinder is characterized by comprising a cylinder body (1), a primary rod assembly and a secondary rod assembly, wherein the cylinder body (1) is divided into an upper oil cavity (2) and a lower oil cavity (3), the primary rod assembly is sleeved in the upper oil cavity (2), the secondary rod assembly is sleeved in the primary rod assembly, a first oil hole (4) and a second oil hole (5) are formed in the upper oil cavity (2), and a liquid return channel (6) is formed in the primary rod assembly; the inner wall of the primary rod assembly is provided with a plurality of groups of annular grooves (7), the annular grooves (7) are uniformly distributed along the axial direction, each group of annular grooves (7) consists of a primary groove (8) and a secondary groove (9), and the secondary groove (9) is arranged at the bottom of the primary groove (8); a plurality of radial blind holes (10) with uniformly distributed circumferences are formed in the side wall of the bottom of the secondary rod assembly, a clamping block (11) is arranged in each blind hole (10), a spring (12) is arranged between the clamping block (11) and the bottom of the blind hole (10), and when the clamping block (11) is opposite to the annular groove (7) in the outward extending process of the secondary rod assembly, the clamping block (11) extends outwards under the action of the spring (12) to be clamped into the primary groove (8); the upper side of the primary groove (8) is an arc surface, and the clamping block (11) can upwards pass through the annular groove (7) when the secondary rod assembly extends out; a plunger (13) is arranged in the lower oil cavity (3), the lower end of the plunger (13) extends out of the cylinder body (1), a first communication hole (14) is formed between the upper oil cavity (2) and the lower oil cavity (3), and a pressure valve (15) is arranged on the first communication hole (14);
the primary rod assembly consists of a primary piston (16) and a primary ejection rod (17), the annular groove (7) is formed in the inner wall of the primary ejection rod (17), the secondary rod assembly consists of a secondary piston (18) and a secondary ejection rod (19), and the clamping block (11) is arranged on the outer wall of the secondary piston (18);
an exhaust hole (20) is formed in the secondary rod assembly, an upper port of the exhaust hole (20) is positioned at the top of the side wall of the secondary ejector rod (19), and a lower port of the exhaust hole (20) is communicated with the bottoms of the blind holes (10).
2. A multistage hydraulic cylinder according to claim 1, characterized in that the axial thickness of the secondary piston (18) is greater than the width of the primary groove (8).
3. A multistage hydraulic cylinder according to claim 1, characterized in that the upper edge of the secondary piston (18) is lower than the upper edge of the primary groove (8) when the clamping block (11) is clamped in the primary groove (8).
4. A multistage hydraulic cylinder according to claim 1, characterized in that a second communication hole (21) is provided between the upper oil chamber (2) and the lower oil chamber (3), and the second communication hole (21) is provided with a switch valve (22).
5. A multistage hydraulic cylinder according to claim 1, characterized in that the lower end of the bottom plunger (13) is provided with a base (23).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111247503.5A CN113969917B (en) | 2021-10-26 | 2021-10-26 | Multistage hydraulic cylinder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111247503.5A CN113969917B (en) | 2021-10-26 | 2021-10-26 | Multistage hydraulic cylinder |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113969917A CN113969917A (en) | 2022-01-25 |
| CN113969917B true CN113969917B (en) | 2023-07-07 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111247503.5A Active CN113969917B (en) | 2021-10-26 | 2021-10-26 | Multistage hydraulic cylinder |
Country Status (1)
| Country | Link |
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| CN (1) | CN113969917B (en) |
Family Cites Families (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1526960A (en) * | 2003-09-25 | 2004-09-08 | 浙江大学 | Single rod equal area double acting hydraulic cylinder capable of balancing weight |
| CN101787989A (en) * | 2009-01-23 | 2010-07-28 | 徐洪德 | Multi-level piston two-way hydraulic cylinder |
| JP2011247373A (en) * | 2010-05-28 | 2011-12-08 | Ishimori Seisakusho:Kk | Multi-stage cylinder device |
| CN201747319U (en) * | 2010-07-15 | 2011-02-16 | 江苏省金峰石油机械制造有限公司 | Reverse-pressurizing multi-stage expansion cylinder |
| CN203641170U (en) * | 2013-09-27 | 2014-06-11 | 北京航天发射技术研究所 | Steel ball lock and interference external lock combined locking type hydraulic cylinder |
| CN203670349U (en) * | 2014-01-22 | 2014-06-25 | 烟台未来自动装备有限责任公司 | Single-action multi-stage plunger type hydraulic cylinder with controllable stretching sequence |
| CN106640840B (en) * | 2017-01-22 | 2018-03-06 | 重庆市巴山液压附件厂有限公司 | A kind of double-stage double-acting for scout car lifts hydraulic jack |
| CN207229508U (en) * | 2017-10-13 | 2018-04-13 | 烟台未来自动装备有限责任公司 | A kind of nothing changes the single-acting two-stage hydraulic cylinder of level impact |
| CN207660928U (en) * | 2017-11-24 | 2018-07-27 | 郑州煤机综机设备有限公司 | A kind of multistage hydraulic cylinder and the dress cylinder machine using the multistage hydraulic cylinder |
| CN111503088B (en) * | 2020-05-07 | 2022-04-29 | 山东万通液压股份有限公司 | Single-telescopic thrust multiplication hydraulic cylinder |
| CN113530915A (en) * | 2021-08-25 | 2021-10-22 | 马庆国 | Self-locking type single-action hydraulic cylinder |
-
2021
- 2021-10-26 CN CN202111247503.5A patent/CN113969917B/en active Active
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| CN113969917A (en) | 2022-01-25 |
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Effective date of registration: 20230607 Address after: 257000 No.516, Huanghekou Trade City, Xi'er Road, Dongying District, Dongying, Shandong Province Applicant after: Dongying Daoer industry and Trade Co.,Ltd. Address before: 450000 family courtyard of machinery department, No. 15, Jingwu Road, Jinshui District, Zhengzhou City, Henan Province Applicant before: Ma Qingguo |
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