CN112855651A - High-precision hydraulic cylinder - Google Patents
High-precision hydraulic cylinder Download PDFInfo
- Publication number
- CN112855651A CN112855651A CN201911097535.4A CN201911097535A CN112855651A CN 112855651 A CN112855651 A CN 112855651A CN 201911097535 A CN201911097535 A CN 201911097535A CN 112855651 A CN112855651 A CN 112855651A
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- Prior art keywords
- hydraulic cylinder
- oil
- oil port
- piston
- hydraulic
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- Pending
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- 238000001514 detection method Methods 0.000 claims description 16
- 238000006073 displacement reaction Methods 0.000 claims description 3
- 238000007789 sealing Methods 0.000 abstract description 13
- 239000003921 oil Substances 0.000 description 51
- 239000010720 hydraulic oil Substances 0.000 description 21
- 239000012530 fluid Substances 0.000 description 8
- 238000003754 machining Methods 0.000 description 4
- 238000000034 method Methods 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
- 238000005491 wire drawing Methods 0.000 description 1
Images
Classifications
-
- 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
- F15B15/1428—Cylinders
-
- 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
-
- 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
- F15B19/00—Testing; Calibrating; Fault detection or monitoring; Simulation or modelling of fluid-pressure systems or apparatus not otherwise provided for
- F15B19/005—Fault detection or monitoring
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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 the technical field of oil cylinders, in particular to a hydraulic cylinder. The high-precision hydraulic cylinder comprises a hydraulic cylinder body, wherein the hydraulic cylinder body comprises a cylinder barrel, a cylinder cover, a piston and a piston rod, a first cavity and a second cavity are arranged in the cylinder barrel, the first cavity is communicated with a first oil port, the second cavity is communicated with a second oil port, the first oil port is connected with a first oil pipe, the second oil port is connected with a second oil pipe, and throttle valves are respectively arranged on the first oil pipe and the second oil pipe; the piston and the piston rod in the cylinder barrel are rigidly connected with the cylinder barrel. By adopting the technical scheme, the hydraulic cylinder has the advantages that the structure that the traditional hydraulic cylinder is provided with the sealing device is abandoned, the rigid structure is adopted, and the leakage amount of the hydraulic cylinder is adjusted in a throttling valve compensation mode, so that the hydraulic cylinders with different characteristics can be better controlled.
Description
Technical Field
The invention relates to the technical field of oil cylinders, in particular to a hydraulic cylinder.
Background
The hydraulic cylinder is a hydraulic actuator which converts hydraulic energy into mechanical energy and performs linear reciprocating motion or swinging motion. The hydraulic cylinder has simple structure and reliable work, can remove a speed reducer when realizing reciprocating motion, has no transmission clearance and stable motion, and is widely applied to hydraulic systems of various machines. As shown in fig. 1, the hydraulic cylinder is basically composed of a cylinder head 1, a cylinder tube 2, a piston 3, a piston rod 4, a sealing device 5, and the like.
In the process of machining the hydraulic cylinder, sealing devices such as sealing rings and the like are usually required to be arranged at the piston and other joints inside the cylinder barrel, but the sealing rings cause friction, so that the control precision is influenced. Particularly, when a plurality of hydraulic cylinders need to be controlled at the same time, the characteristics of the hydraulic cylinders are desired to be the same, but the clearances of the hydraulic cylinders are different, which causes different characteristics and is troublesome to control. If the sealing device is removed, leakage problems may arise due to the clearance of the hydraulic cylinder. As the machining accuracy is higher, the amount of leakage is reduced. However, in order to reduce the amount of leakage and improve the machining accuracy, the machining cost is greatly increased.
Disclosure of Invention
The invention aims to provide a high-precision hydraulic cylinder to solve the technical problem.
The technical problem solved by the invention can be realized by adopting the following technical scheme:
the high-precision hydraulic cylinder comprises a hydraulic cylinder body, wherein the hydraulic cylinder body comprises a cylinder barrel, a cylinder cover, a piston and a piston rod, a first cavity and a second cavity are arranged in the cylinder barrel, the first cavity is communicated with a first oil port, the second cavity is communicated with a second oil port, the first oil port is connected with a first oil pipe, the second oil port is connected with a second oil pipe, and throttle valves are respectively arranged on the first oil pipe and the second oil pipe;
the piston and the piston rod in the cylinder are rigidly connected with the cylinder.
The original sealing device is removed, the piston and the piston rod in the cylinder barrel are not provided with sealing devices such as sealing rings and the like, the piston or the piston rod is rigidly connected with the cylinder barrel, and the hydraulic oil leakage problem can be caused because a gap exists in the main body of the hydraulic cylinder. In order to realize convenient control of the hydraulic cylinder bodies, the conveyed hydraulic oil is controlled by the throttle valves additionally arranged on the first oil pipe and the second oil pipe for conveying the hydraulic oil, so that the leakage of the hydraulic oil of each hydraulic cylinder body is approximate as much as possible. When the hydraulic cylinder main bodies are controlled, the leakage amount of the hydraulic cylinder main bodies is adjusted to be similar through throttle valve compensation, and the hydraulic cylinders are conveniently adjusted under the condition that a part of the leakage amount is wasted, so that better control is achieved.
And a measuring cup is arranged outside the first oil port or the second oil port, and the measuring cup is detachably arranged on the outer surface of the hydraulic cylinder main body. In order to further determine the leakage amount of the hydraulic cylinder main body and to facilitate better adjustment of the throttle valve, the hydraulic cylinder can prop against the piston, hydraulic oil with certain pressure is input into one of the first oil port and the second oil port, the measuring cup is placed at the other oil port to receive the hydraulic oil, and the oil amount is detected according to a preset time, such as one minute, and is the leakage amount per minute. The opening degree of the throttle valve is determined based on the leakage amount.
And a support groove is formed in the outer surface of the hydraulic cylinder main body, the measuring cup is placed in the support groove, and the open port of the measuring cup is positioned below the first oil port or the second oil port. Because the detection to letting out leakage quantity is usually in control pneumatic cylinder main part earlier stage, when pneumatic cylinder main part normal operating, need not to detect, consequently adopt above-mentioned structure after, when the detection lets out leakage quantity, arrange the graduated flask in on supporting the groove. When the detection is not needed, the measuring cup is taken down.
The oil pipe is characterized by further comprising a pressure sensor, wherein the pressure sensor is arranged on an oil path between the first oil pipe and the second oil pipe. When the leakage amount needs to be detected, the pressurized hydraulic oil needs to be conveyed to the first oil port or the second oil port, and in order to accurately detect the leakage amount, the pressurized hydraulic oil is detected and fed back through the pressure sensor.
The leakage detection device further comprises a position sensor, wherein the position sensor is used for detecting the position of the piston, and then determining the position of a detection point when the leakage amount is detected. When the leakage amount is detected, the leakage amount is detected for a plurality of detection points in addition to the leakage amount after the piston is abutted, so that the compensation factor of the throttle valve can be finally determined.
The position sensor can adopt an external wire-drawing encoder or a laser position sensor.
The position sensor can also adopt a built-in linear displacement sensor.
Has the advantages that: by adopting the technical scheme, the hydraulic cylinder has the advantages that the structure that the traditional hydraulic cylinder is provided with the sealing device is abandoned, the rigid structure is adopted, and the leakage amount of the hydraulic cylinder is adjusted in a throttling valve compensation mode, so that the hydraulic cylinders with different characteristics can be better controlled.
Drawings
FIG. 1 is a schematic diagram of a prior art hydraulic cylinder;
FIG. 2 is a schematic view of a connection of the hydraulic cylinder of the present invention.
Detailed Description
In order to make the technical means, the creation characteristics, the achievement purposes and the effects of the invention easy to understand, the invention is further described with the specific drawings.
Referring to fig. 2, high accuracy pneumatic cylinder, including the pneumatic cylinder main part, the pneumatic cylinder main part includes cylinder 11, cylinder cap, piston 12 and piston rod 13, includes first cavity 21 and second cavity 22 in the cylinder 11, the first hydraulic fluid port of first cavity 21 UNICOM, the second hydraulic fluid port of second cavity 22 UNICOM. The first chamber 21 is a cavity A, the second chamber 22 is a cavity B, the first oil port is an opening A, and the second oil port is an opening B. The first oil port is connected with the first oil pipe 31, the second oil port is connected with the second oil pipe 32, and the throttle valves 4 are respectively arranged on the first oil pipe 31 and the second oil pipe 32. The piston 12 and the piston rod 13 in the cylinder 11 are rigidly connected to the cylinder 11. The original sealing device is removed, the piston 12 and the piston rod 13 in the cylinder barrel 11 are not provided with sealing devices such as sealing rings, and the like, and the piston 12 or the piston rod 13 is in rigid connection with the cylinder barrel 11 at the moment, so that the hydraulic oil leakage problem can be caused due to the existence of a gap in the hydraulic cylinder body. In order to realize convenient control of a plurality of hydraulic cylinder bodies, the conveyed hydraulic oil is controlled by the throttle valves 4 additionally arranged on the first oil pipe 31 and the second oil pipe 32 for conveying the hydraulic oil, so that the hydraulic oil leakage of each hydraulic cylinder body is approximate as much as possible. When the hydraulic cylinder bodies are controlled, the throttle valve 4 is used for compensating, the hydraulic cylinder bodies are adjusted to have similar leakage amount, and the hydraulic cylinders are convenient to adjust under the condition of wasting a part of leakage amount so as to achieve better control.
A measuring cup is arranged outside the first oil port or the second oil port, and the measuring cup is detachably arranged on the outer surface of the hydraulic cylinder main body. The graduated flask can adopt plastics or glass graduated flask, and the position that sets up of graduated flask is confirmed according to first hydraulic fluid port or the position of second hydraulic fluid port in the pneumatic cylinder main part, only need confirm the open mouth of graduated flask be located first hydraulic fluid port or second hydraulic fluid port under can to the graduated flask can receive the hydraulic oil that first hydraulic fluid port or second hydraulic fluid port flow. In order to further determine the leakage amount of the hydraulic cylinder body so as to better adjust the throttle valve 4, the hydraulic cylinder can prop against the piston 12, hydraulic oil with certain pressure is input into one of the first oil port and the second oil port, the measuring cup is placed at the other oil port to receive the hydraulic oil, and the oil amount is detected according to a preset time, such as one minute, and is the leakage amount per minute. The opening degree of the throttle valve 4 is determined according to the leakage amount. The outer surface of the hydraulic cylinder main body is provided with a supporting groove, and the supporting groove can be fixed with the hydraulic cylinder main body through the existing modes such as clamping, welding or bolts. The measuring cup is placed in the supporting groove, and the open port of the measuring cup is positioned below the first oil port or the second oil port. Because the detection to letting out leakage quantity is usually in control pneumatic cylinder main part earlier stage, when pneumatic cylinder main part normal operating, need not to detect, consequently adopt above-mentioned structure after, when the detection lets out leakage quantity, arrange the graduated flask in on supporting the groove. When the detection is not needed, the measuring cup is taken down.
And a pressure sensor provided on an oil path between the first oil pipe 31 and the second oil pipe 32. When the leakage amount needs to be detected, the pressurized hydraulic oil needs to be conveyed to the first oil port or the second oil port, and in order to accurately detect the leakage amount, the pressurized hydraulic oil is detected and fed back through the pressure sensor.
And the device also comprises a position sensor, wherein the position sensor is used for detecting the position of the piston 12 so as to determine the position of a detection point when the leakage quantity is detected. When the leakage amount is detected, in addition to the leakage amount after abutting against the piston 12, the leakage amount is detected for each of the plurality of detection points, so that the compensation factor of the throttle valve 4 is finally determined. The position sensor may be provided in a manner of detecting the position of the piston 12 in a conventional manner. The position sensor can adopt an external wire pulling encoder or a laser position sensor. The position sensor may also be a built-in linear displacement sensor.
When a plurality of hydraulic cylinder bodies of the invention are controlled by a control system, firstly, the leakage amount of the hydraulic cylinder bodies is detected, and the following method is adopted during detection:
1) as shown in fig. 2, P is an oil inlet, T is an oil return port, the piston 12 abuts against the port a, hydraulic oil with a certain pressure is input into the port a, the port B is connected with the hydraulic oil through the measuring cup, and after one minute, the oil amount of the hydraulic oil in the measuring cup is checked, namely the leakage amount per minute of the hydraulic cylinder body.
2) And (2) inputting hydraulic oil with another pressure into the port A in the same way as the step 1), and detecting the leakage amount until the leakage amount under a plurality of pressures is obtained.
3) The piston 12 moves, and the leakage amount is detected at the plurality of detection points respectively in the same manner as in step 1) and step 2), so that the leakage amount at the plurality of detection points under the plurality of pressures is obtained.
4) And respectively compensating the throttle valve of each hydraulic cylinder body according to the leakage amount of a plurality of detection points under a plurality of pressures, so that the plurality of hydraulic cylinder bodies obtain the leakage amount which is similar as much as possible under a certain pressure.
The foregoing shows and describes the general principles and broad features of the present invention and advantages thereof. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.
Claims (7)
1. The high-precision hydraulic cylinder comprises a hydraulic cylinder body, wherein the hydraulic cylinder body comprises a cylinder barrel, a cylinder cover, a piston and a piston rod, a first cavity and a second cavity are arranged in the cylinder barrel, the first cavity is communicated with a first oil port, the second cavity is communicated with a second oil port, the first oil port is connected with a first oil pipe, and the second oil port is connected with a second oil pipe;
the piston and the piston rod in the cylinder are rigidly connected with the cylinder.
2. The high-precision hydraulic cylinder according to claim 1, wherein a measuring cup is arranged outside the first oil port or the second oil port, and the measuring cup is detachably arranged on the outer surface of the hydraulic cylinder main body.
3. The high-precision hydraulic cylinder according to claim 2, wherein a support groove is formed in an outer surface of the cylinder body, the measuring cup is placed in the support groove, and an open opening of the measuring cup is located below the first oil port or the second oil port.
4. A high accuracy hydraulic cylinder according to claim 1, further comprising a pressure sensor provided on an oil path between the first oil line to the second oil line.
5. The high-precision hydraulic cylinder according to claim 1, further comprising a position sensor for detecting a position of the piston to determine a position of a detection point at which the leakage amount is detected.
6. A high accuracy hydraulic cylinder according to claim 5, wherein the position sensor is an external wire-pull encoder or a laser position sensor.
7. A high accuracy hydraulic cylinder according to claim 5, characterized in that the position sensor is a built-in linear displacement sensor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911097535.4A CN112855651A (en) | 2019-11-12 | 2019-11-12 | High-precision hydraulic cylinder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911097535.4A CN112855651A (en) | 2019-11-12 | 2019-11-12 | High-precision hydraulic cylinder |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112855651A true CN112855651A (en) | 2021-05-28 |
Family
ID=75984147
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911097535.4A Pending CN112855651A (en) | 2019-11-12 | 2019-11-12 | High-precision hydraulic cylinder |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112855651A (en) |
Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH06241209A (en) * | 1993-02-10 | 1994-08-30 | Mitsubishi Heavy Ind Ltd | Leakage oil recoverying device of hydraulic cylinder |
| KR20010086962A (en) * | 2000-03-06 | 2001-09-15 | 제재근 | Apparatus for collecting oil leakage of hydraulic cylinder |
| CN203321939U (en) * | 2013-05-27 | 2013-12-04 | 徐州力成液压设备有限公司 | Hydraulic cylinder internal leakage composite detection system |
| CN203412845U (en) * | 2013-06-25 | 2014-01-29 | 南京梅山冶金发展有限公司 | Portable online oil cylinder internal leakage detecting device |
| CN204664052U (en) * | 2015-06-05 | 2015-09-23 | 嘉兴学院 | A kind of dither static pressure supporting cylinder |
| CN105298988A (en) * | 2015-11-13 | 2016-02-03 | 湖南省产商品质量监督检验研究院 | Hydraulic cylinder internal leakage testing device and method |
| CN205298134U (en) * | 2015-12-14 | 2016-06-08 | 安徽凯莎工业设备制造有限公司 | Hydraulic oil cylinder |
| CN105697460A (en) * | 2016-04-25 | 2016-06-22 | 中冶赛迪工程技术股份有限公司 | High-precision hydraulic cylinder inner-leakage detection device |
| CN206072013U (en) * | 2016-08-31 | 2017-04-05 | 广东天恒液压机械有限公司 | A kind of clearance seal formula piston structure without sealing member |
| CN109915434A (en) * | 2019-01-17 | 2019-06-21 | 李军 | It is a kind of using oil-water media without sealing ring hydraulic cylinder |
| CN110307206A (en) * | 2019-06-21 | 2019-10-08 | 同济大学 | A kind of low internal leakage anti-bias load cylinder device |
-
2019
- 2019-11-12 CN CN201911097535.4A patent/CN112855651A/en active Pending
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH06241209A (en) * | 1993-02-10 | 1994-08-30 | Mitsubishi Heavy Ind Ltd | Leakage oil recoverying device of hydraulic cylinder |
| KR20010086962A (en) * | 2000-03-06 | 2001-09-15 | 제재근 | Apparatus for collecting oil leakage of hydraulic cylinder |
| CN203321939U (en) * | 2013-05-27 | 2013-12-04 | 徐州力成液压设备有限公司 | Hydraulic cylinder internal leakage composite detection system |
| CN203412845U (en) * | 2013-06-25 | 2014-01-29 | 南京梅山冶金发展有限公司 | Portable online oil cylinder internal leakage detecting device |
| CN204664052U (en) * | 2015-06-05 | 2015-09-23 | 嘉兴学院 | A kind of dither static pressure supporting cylinder |
| CN105298988A (en) * | 2015-11-13 | 2016-02-03 | 湖南省产商品质量监督检验研究院 | Hydraulic cylinder internal leakage testing device and method |
| CN205298134U (en) * | 2015-12-14 | 2016-06-08 | 安徽凯莎工业设备制造有限公司 | Hydraulic oil cylinder |
| CN105697460A (en) * | 2016-04-25 | 2016-06-22 | 中冶赛迪工程技术股份有限公司 | High-precision hydraulic cylinder inner-leakage detection device |
| CN206072013U (en) * | 2016-08-31 | 2017-04-05 | 广东天恒液压机械有限公司 | A kind of clearance seal formula piston structure without sealing member |
| CN109915434A (en) * | 2019-01-17 | 2019-06-21 | 李军 | It is a kind of using oil-water media without sealing ring hydraulic cylinder |
| CN110307206A (en) * | 2019-06-21 | 2019-10-08 | 同济大学 | A kind of low internal leakage anti-bias load cylinder device |
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| PB01 | Publication | ||
| PB01 | Publication | ||
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Application publication date: 20210528 |