CN108999832B - Self-locking hydraulic cylinder - Google Patents
Self-locking hydraulic cylinder Download PDFInfo
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- CN108999832B CN108999832B CN201810873544.7A CN201810873544A CN108999832B CN 108999832 B CN108999832 B CN 108999832B CN 201810873544 A CN201810873544 A CN 201810873544A CN 108999832 B CN108999832 B CN 108999832B
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- self
- piston rod
- frame body
- locking
- sliding
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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
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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
- F15B15/20—Other details, e.g. assembly with regulating devices
- F15B15/26—Locking mechanisms
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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 application relates to the technical field of hydraulic equipment and discloses a self-locking hydraulic cylinder which comprises an outer cylinder barrel, an inner cylinder barrel and a piston rod, wherein a sliding groove is formed in the inner wall of the inner cylinder barrel, a self-locking pin is installed in the sliding groove, and a self-locking groove matched with the self-locking pin is formed in the piston rod; a locking device is also arranged in the outer cylinder barrel and comprises a frame body, a chain wheel and chain mechanism and a roller wheel, a clamping plate is connected in the frame body in a sliding manner, a supporting rod is connected in the frame body in a sliding manner, and a rack is arranged at one end of the supporting rod, which extends out of the frame body; the roller is abutted against the piston rod, the roller is coaxially connected with one of the chain wheels of the chain wheel and chain mechanism, the other chain wheel of the chain wheel and chain mechanism is coaxially connected with a gear, and the gear is meshed with the rack on the supporting rod. The piston rod of the hydraulic cylinder can retract, the locking device opens the self-locking protection, and the clamping plate clamps and fixes the piston rod in the radial direction, so that the retraction of the piston rod is overcome, and the piston rod is kept at the current position to work stably.
Description
Technical Field
The invention relates to the technical field of hydraulic equipment, in particular to a self-locking hydraulic cylinder.
Background
The hydraulic cylinder is an important element widely applied to the modern industrial hydraulic industry, is a hydraulic actuating element which converts hydraulic energy into mechanical energy and makes linear reciprocating motion (or swinging motion), and has simple structure and reliable operation. When the reciprocating motion is realized by the hydraulic cylinder, a speed reducing device can be omitted, no transmission gap exists, and the motion is stable, so that the hydraulic cylinder is widely applied to hydraulic systems of various machines.
When the hydraulic cylinder works, after a piston rod of the hydraulic cylinder extends out, the piston rod needs to stably work at the current position, and the piston rod can neither extend out nor retract, namely, the piston rod is generally called self-locking.
Disclosure of Invention
The invention aims to provide a self-locking hydraulic cylinder to solve the problems that in the prior art, self-locking is realized by using a hydraulic reversing valve, the self-locking effect is poor, and the safety coefficient is low.
In order to achieve the above purpose, the basic scheme of the invention is as follows: a self-locking hydraulic cylinder comprises an outer cylinder barrel, an inner cylinder barrel and a piston rod, wherein the inner cylinder barrel is fixedly arranged in the outer cylinder barrel, a piston is connected in the inner cylinder barrel in a sliding manner, one end of the piston rod is fixedly connected with the piston, the other end of the piston rod penetrates through the outer cylinder barrel and the inner cylinder barrel, and the piston rod is respectively matched with the outer cylinder barrel and the inner cylinder barrel in a sliding way, the inner wall of the inner cylinder barrel is provided with a sliding chute, a sealing plate for sealing the sliding chute is arranged at the notch of the sliding chute, a sliding plate is connected in the sliding chute in a sliding way, the sliding plate divides the sliding chute into a first chamber and a second chamber, the side wall of the inner cylinder barrel is provided with an oil injection channel communicated with the first chamber, the bottom of the sliding plate and the sliding groove is connected with a first spring, a self-locking pin is fixedly arranged on the sliding plate, the part of the self-locking pin, which is far away from the sliding plate, extends into the inner cylinder barrel, and a self-locking groove matched with the self-locking pin is arranged on the piston rod; the outer cylinder barrel is internally provided with a locking device, the locking device comprises a frame body and a chain wheel and chain mechanism, the piston rod penetrates through the frame body and is in sliding fit with the frame body, the interior of the frame body is divided into two areas, each area is provided with a locking structure, each locking structure comprises a clamping plate in sliding fit with the frame body, the clamping plate and the bottom surface of the frame body are connected with a second spring, the frame body is in sliding connection with a supporting rod, the supporting rod extends into the frame body and is fixedly connected with the clamping plate, and one end, extending out of the frame body, of the supporting rod is provided with; articulated in the framework have the hinge bar, the hinge bar is equipped with the torsional spring with the articulated department of framework, the one end that the framework was kept away from to the hinge bar rotates and is connected with the gyro wheel, the side of gyro wheel offsets with the piston rod all the time, one of them sprocket coaxial coupling of gyro wheel and sprocket chain mechanism, another sprocket coaxial coupling of sprocket chain mechanism has the gear, rack intermeshing on gear and the bracing piece.
The working principle of the basic scheme is as follows: when the piston rod is stretched to a certain position, the self-locking pin is clamped into the self-locking groove on the piston rod under the action of the elastic force of the first spring to lock the piston rod, and primary locking is realized. Meanwhile, under the action of the elastic force of the second spring, the two clamping plates in the frame body of the locking device can clamp the part of the piston rod extending out of the inner cylinder barrel, the piston rod is radially clamped and fixed, secondary locking is realized, and finally the piston rod stably works at the current position.
After the hydraulic cylinder works for a long time, the piston rod of the hydraulic cylinder can retract, namely the piston rod can slide in the inner cylinder barrel. At the moment, the locking device opens the self-locking protection, connect the torsional spring between hinge bar and framework, make the gyro wheel of hinge bar tip offset with the piston rod all the time, slide in the piston rod inner cylinder and drive the gyro wheel and rotate, the gyro wheel rotates and drives rather than a sprocket rotation in the engaged sprocket chain mechanism, thereby make sprocket chain mechanism begin to operate, another sprocket rotates thereupon, thereby drive rather than the engaged gear begin to rotate, the gear rotation drives rather than the engaged bracing piece takes place to remove, the bracing piece is at the in-process that removes, extrude the grip block, thereby make two upper and lower grip blocks more firm to the centre gripping of piston rod, thereby overcome the withdrawal action of piston rod, carry out the self-locking protection to the piston rod, make the piston rod still keep working at current position stable.
The beneficial effect of this scheme: 1. when the self-locking device works, the self-locking pin is clamped into the self-locking groove on the piston rod under the action of the elastic force of the first spring to lock the piston rod, so that primary locking is realized. 2. Two clamping plates in the frame of the locking device can clamp the part of the piston rod extending out of the inner cylinder barrel under the action of the elastic force of the second spring, and the piston rod is radially clamped and fixed, so that secondary locking is realized. 3. When the piston rod retracts, the roller abutting against the piston rod senses the movement of the piston rod, and the supporting rod moves and extrudes the clamping plates through the chain wheel and chain mechanism and the gear, so that the upper clamping plate and the lower clamping plate are more firm to clamp the piston rod, the retraction movement of the piston rod is overcome, the self-locking protection is carried out on the piston rod, and the piston rod still keeps working stably at the current position. 4. This scheme simple structure, the auto-lock is effectual, and factor of safety is high.
Further, the clamping plate is coated with a rubber layer. The friction force between the clamping plate and the piston rod is increased, so that the retraction action of the piston rod is overcome more effectively.
Further, the clamping plate is arc-shaped. The clamping plate is fully attached to the surface of the piston rod, so that the clamping plate is favorable for clamping and fixing the piston rod, and the retraction action of the piston rod is overcome.
Further, the diameter of the gear is larger than that of a chain wheel in the chain wheel and chain mechanism. The piston rod has the advantages that the stroke amplification effect is achieved, when the piston rod retracts slightly, the supporting rod can extrude the clamping plate, the clamping plate can clamp and fix the piston rod, and therefore the retracting action of the piston rod is overcome timely.
Furthermore, a pull rope is connected to the hinged rod. During unlocking, the pull rope is pulled to enable the roller to be separated from mutual interference with the piston rod, so that the clamping plate reduces locking of the piston rod, and the hydraulic cylinder realizes unlocking.
Further, the roller is coated with a rubber layer. The friction force between the roller and the piston rod is increased, so that the phenomenon of slipping is prevented, the locking device can lock the piston rod in time, and the retraction action of the piston rod is overcome.
Drawings
FIG. 1 is a cross-sectional view of a self-locking hydraulic cylinder according to an embodiment of the present invention;
FIG. 2 is a cross-sectional view of an inner cylinder barrel according to an embodiment of the present invention;
fig. 3 is a schematic structural diagram of a locking device according to an embodiment of the invention.
Detailed Description
The present invention will be described in further detail below by way of specific embodiments:
reference numerals in the drawings of the specification include: the device comprises an outer cylinder barrel 1, an inner cylinder barrel 2, a piston 21, a piston rod 22, a self-locking groove 23, a locking device 3, a sliding groove 4, a first chamber 41, a second chamber 42, an oil filling channel 43, a sliding plate 5, a self-locking pin 51, a first spring 52, a sealing plate 53, a frame 6, a clamping plate 61, a second spring 62, a support rod 63, a rack 64, a chain wheel and chain mechanism 7, a chain wheel 71, a gear 72, a hinge rod 8, a torsion spring 81 and a roller 9.
Embodiments are substantially as shown in figures 1 to 3 of the accompanying drawings: a self-locking hydraulic cylinder comprises an outer cylinder barrel 1, an inner cylinder barrel 2 and a piston rod 22, wherein the inner cylinder barrel 2 is fixedly arranged in the outer cylinder barrel 1. The piston 21 is connected in the inner cylinder 2 in a sliding mode, one end of the piston rod 22 is fixedly connected with the piston 21, the other end of the piston rod 22 penetrates through the outer cylinder 1 and the inner cylinder 2, and the piston rod 22 is in sliding fit with the outer cylinder 1 and the inner cylinder 2 respectively. Seted up spout 4 on the inner wall of interior cylinder 2, the notch department of spout 4 is equipped with the closing plate 53 that is used for sealed spout 4, sliding connection has slide 5 in the spout 4, and slide 5 separates spout 4 for first cavity 41 and second cavity 42, is equipped with the oiling passageway 43 with first cavity 41 intercommunication on the lateral wall of interior cylinder 2, installs first spring 52 between slide 5 and spout 4, first spring 52 both ends are connected with slide 5 and spout 4 bottom respectively. The upper end surface of the sliding plate 5 is fixedly provided with a self-locking pin 51, the part of the self-locking pin 51 far away from the sliding plate 5 extends into the inner cylinder 2, the piston rod 22 is provided with a self-locking groove 23, and the self-locking pin 51 can extend into the self-locking groove 23. The locking device 3 is further arranged in the outer cylinder barrel 1, the locking device 3 comprises a frame body 6 and a chain wheel and chain mechanism 7, and the piston rod 22 penetrates through the frame body 6 and is in sliding fit with the frame body 6. The piston rod 22 divides the interior of the frame 6 into two regions, each of which is provided with a locking structure. The locking structure comprises a clamping plate 61 in sliding fit with the frame body, a second spring 62 is connected between the clamping plate 61 and the bottom surface of the frame body 6, a supporting rod 63 is connected in the frame body 6 in a sliding manner, the supporting rod 63 extends into the frame body 6 and is fixedly connected with the clamping plate 61, and a rack 64 is arranged at one end, extending out of the frame body 6, of the supporting rod 63; the frame body 6 is hinged to a hinge rod 8, a torsion spring 81 is arranged at the hinged position of the hinge rod 8 and the frame body 6, one end, far away from the frame body 6, of the hinge rod 8 is rotatably connected with a roller 9, the side face of the roller 9 is always abutted to the piston rod 22, the roller 9 is coaxially connected with one of the chain wheels 71 of the chain wheel and chain mechanism 7, the other chain wheel 71 of the chain wheel and chain mechanism 7 is coaxially connected with a gear 72, and the gear 72 is meshed with the rack 64 on the support rod 63.
Specifically, the grip plate 61 and the roller 9 are covered with rubber layers. The diameter of the gear 72 is larger than the diameter of the sprocket 71 in the sprocket-chain mechanism 7.
The specific implementation mode of the scheme is as follows: when the piston rod 22 extends to a certain position, the self-locking pin 51 is clamped into the self-locking groove 23 on the piston rod 22 under the action of the elastic force of the first spring 52, so that the piston rod 22 is locked, and primary locking is realized. Meanwhile, under the action of the elastic force of the second spring 62, the two clamping plates 61 in the frame 6 of the locking device 3 clamp the part of the piston rod 22 extending out of the inner cylinder 2, so as to radially clamp and fix the piston rod 22, thereby realizing secondary locking and finally enabling the piston rod 22 to stably work at the current position.
After the hydraulic cylinder works for a long time, the piston rod 22 of the hydraulic cylinder retracts, that is, the piston rod 22 slides towards the inner cylinder 2. At this time, the locking device 3 opens the self-locking protection, the torsion spring 81 connected between the hinge rod 8 and the frame body 6, so that the roller 9 at the end of the hinged rod 8 always abuts against the piston rod 22, the piston rod 22 slides in the cylinder 2 to drive the roller 9 to rotate, the roller 9 rotates to drive one chain wheel 71 in the chain wheel and chain mechanism 7 engaged with the roller to rotate, so that the chain wheel and chain mechanism 7 starts to operate, the other chain wheel 71 rotates along with the chain wheel, the gear 72 meshed with the chain wheel is driven to rotate, the gear 72 rotates to drive the supporting rod 63 meshed with the gear to move, and in the moving process of the supporting rod 63, the clamping plates 61 are pressed, so that the clamping of the piston rod 22 by the upper and lower clamping plates 61 is firmer, the retraction action of the piston 21 rod is overcome, the piston rod 22 is self-locked to ensure that the piston rod 22 still keeps working stably at the current position.
After the hydraulic cylinder finishes working, the piston rod 22 needs to be unlocked, hydraulic oil is injected into the oil injection channel 43 on the side wall of the inner cylinder barrel 2 until the first chamber 41 is filled with the hydraulic oil, the sliding plate 5 in the sliding groove 4 is extruded by the hydraulic oil, and when the hydraulic pressure is larger than the elastic force of the first spring 52, the self-locking pin 51 locked in the self-locking groove 23 retracts inwards to separate from locking of the piston rod 22. Meanwhile, the hinge rod 8 is pulled through the pull rope, the roller 9 on the hinge rod 8 is not abutted to the piston rod 22 any more, so that the supporting rod 63 is enabled to release the extrusion on the clamping plate 61, the clamping effect of the clamping plate 61 on the piston rod 22 is greatly reduced, the piston rod 22 is released to perform self-locking protection, and the hydraulic cylinder is enabled to realize unlocking.
The foregoing is merely an example of the present invention and common general knowledge of known specific structures and features of the embodiments is not described herein in any greater detail. It should be noted that, for those skilled in the art, without departing from the structure of the present invention, several changes and modifications can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicability of the patent. The scope of the claims of the present application shall be determined by the contents of the claims, and the description of the embodiments and the like in the specification shall be used to explain the contents of the claims.
Claims (5)
1. A self-locking hydraulic cylinder is characterized in that: the piston rod is respectively matched with the outer cylinder barrel and the inner cylinder barrel in a sliding manner, a sliding groove is formed in the inner wall of the inner cylinder barrel, a sealing plate used for sealing the sliding groove is arranged at a notch of the sliding groove, a sliding plate is connected in the sliding groove in a sliding manner and divides the sliding groove into a first cavity and a second cavity, an oil filling channel communicated with the first cavity is arranged on the side wall of the inner cylinder barrel, a first spring is connected with the bottom of the sliding plate and the sliding groove, and the first spring is located in the second cavity; the sliding plate is fixedly provided with a self-locking pin, the part of the self-locking pin, which is far away from the sliding plate, extends into the inner cylinder barrel, and the piston rod is provided with a self-locking groove matched with the self-locking pin; the outer cylinder barrel is internally provided with a locking device, the locking device comprises a frame body and a chain wheel and chain mechanism, the piston rod penetrates through the frame body and is in sliding fit with the frame body, the interior of the frame body is divided into two areas, each area is provided with a locking structure, each locking structure comprises a clamping plate in sliding fit with the frame body, the clamping plate and the bottom surface of the frame body are connected with a second spring, the frame body is in sliding connection with a supporting rod, the supporting rod extends into the frame body and is fixedly connected with the clamping plate, and one end, extending out of the frame body, of the supporting rod is provided with; the frame body is hinged with a hinge rod, a torsional spring is arranged at the hinged position of the hinge rod and the frame body, one end of the hinge rod, which is far away from the frame body, is rotatably connected with a roller, the side surface of the roller is always abutted against a piston rod, the roller is coaxially connected with one chain wheel of a chain wheel and chain mechanism, the other chain wheel of the chain wheel and chain mechanism is coaxially connected with a gear, and the gear is meshed with a rack on a support rod; the clamping plate is coated with a rubber layer.
2. The self-locking hydraulic cylinder according to claim 1, wherein: the clamping plate is arc-shaped.
3. The self-locking hydraulic cylinder according to claim 2, wherein: the diameter of the gear is larger than that of a chain wheel in the chain wheel and chain mechanism.
4. The self-locking hydraulic cylinder according to claim 3, wherein: the hinged rod is connected with a pull rope.
5. The self-locking hydraulic cylinder according to claim 4, wherein: the roller is coated with a rubber layer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810873544.7A CN108999832B (en) | 2018-08-02 | 2018-08-02 | Self-locking hydraulic cylinder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810873544.7A CN108999832B (en) | 2018-08-02 | 2018-08-02 | Self-locking hydraulic cylinder |
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| Publication Number | Publication Date |
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| CN108999832A CN108999832A (en) | 2018-12-14 |
| CN108999832B true CN108999832B (en) | 2020-05-12 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201810873544.7A Active CN108999832B (en) | 2018-08-02 | 2018-08-02 | Self-locking hydraulic cylinder |
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Families Citing this family (12)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN109353064A (en) * | 2018-12-24 | 2019-02-19 | 无锡蓝力智能装备有限公司 | Hydraulic press total travel locking mechanism |
| CN110107467B (en) * | 2019-05-13 | 2021-01-08 | 哈尔滨工程大学 | Hydraulic vibration energy recovery device and deceleration strip energy recovery system |
| CN111561491B (en) * | 2020-04-29 | 2022-06-21 | 苏州鑫旭合智能科技有限公司 | Internal and external combined mechanical self-locking hydraulic cylinder |
| CN111550540B (en) * | 2020-05-20 | 2023-04-25 | 张述成 | Rotary driving device |
| CN112046609B (en) * | 2020-07-07 | 2023-08-15 | 阜阳常阳汽车部件有限公司 | Truck frame with rear-end collision protection function |
| CN112943744B (en) * | 2021-02-01 | 2023-03-28 | 河南德佰特机电设备制造有限公司 | Hydraulic cylinder |
| CN114278643A (en) * | 2021-12-31 | 2022-04-05 | 山东福阳液压科技有限公司 | Automobile hydraulic cylinder with self-locking function |
| CN116146179B (en) * | 2023-02-14 | 2024-04-02 | 陕西航天德林科技集团有限公司 | Carbon fiber rod type logging cable injection system and process |
| CN116044861B (en) * | 2023-04-03 | 2023-06-23 | 烟台星辉劳斯堡液压机械有限公司 | Retractile position self-locking hydraulic cylinder |
| CN116201788B (en) * | 2023-04-28 | 2023-07-21 | 沧州精跃液压油缸制造有限公司 | Single-action multistage hydraulic cylinder self-locking device |
| CN116538171B (en) * | 2023-07-03 | 2023-09-15 | 南安市泉信液压机械有限公司 | Hydraulic cylinder locking mechanism |
| CN116875788B (en) * | 2023-07-17 | 2024-04-02 | 南通华东油压科技有限公司 | Aging treatment device for multi-loop hydraulic cylinder casting |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN202247831U (en) * | 2011-08-05 | 2012-05-30 | 四川宏华石油设备有限公司 | Locking device and hydraulic control system thereof |
| CN106593998B (en) * | 2016-12-08 | 2019-01-15 | 泸州长江液压密封件有限公司 | Self-locking hydraulic cylinder is realized by elastic component |
| CN107035742A (en) * | 2017-06-21 | 2017-08-11 | 张多艳 | A kind of novel hydraulic cylinder |
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2018
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