CN117967642B - Two-stage expansion cylinder self-locking multi-stage hydraulic cylinder - Google Patents
Two-stage expansion cylinder self-locking multi-stage hydraulic cylinder Download PDFInfo
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- CN117967642B CN117967642B CN202410389131.7A CN202410389131A CN117967642B CN 117967642 B CN117967642 B CN 117967642B CN 202410389131 A CN202410389131 A CN 202410389131A CN 117967642 B CN117967642 B CN 117967642B
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- 238000004891 communication Methods 0.000 claims description 16
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- 230000000149 penetrating effect Effects 0.000 claims description 5
- 230000003139 buffering effect Effects 0.000 claims 2
- 238000000034 method Methods 0.000 abstract description 11
- 230000008569 process Effects 0.000 abstract description 11
- 230000008859 change Effects 0.000 abstract description 5
- 230000007613 environmental effect Effects 0.000 abstract description 3
- 230000009286 beneficial effect Effects 0.000 abstract description 2
- 239000003921 oil Substances 0.000 description 69
- 239000010720 hydraulic oil Substances 0.000 description 30
- 230000008602 contraction Effects 0.000 description 8
- 238000007789 sealing Methods 0.000 description 8
- 230000002349 favourable effect Effects 0.000 description 6
- 238000002347 injection Methods 0.000 description 5
- 239000007924 injection Substances 0.000 description 5
- 230000001105 regulatory effect Effects 0.000 description 3
- 229910000831 Steel Inorganic materials 0.000 description 2
- 230000006835 compression Effects 0.000 description 2
- 238000007906 compression Methods 0.000 description 2
- 230000007123 defense Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000005489 elastic deformation Effects 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- 239000010959 steel Substances 0.000 description 2
- 230000009471 action Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 230000001276 controlling effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000001125 extrusion Methods 0.000 description 1
- 238000005429 filling process Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 238000005086 pumping Methods 0.000 description 1
Classifications
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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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- 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
- F15B13/00—Details of servomotor systems ; Valves for servomotor systems
- F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
-
- 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
- F15B13/00—Details of servomotor systems ; Valves for servomotor systems
- F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
- F15B13/027—Check valves
-
- 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
-
- 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 field of hydraulic cylinders, in particular to a two-stage expansion cylinder self-locking multi-stage hydraulic cylinder, wherein an interference connection is arranged between a primary locking sleeve and a cylinder barrel, a gap is formed between a secondary locking sleeve and a primary piston rod at the interference connection position after high-pressure oil is matched for feeding, so that unlocking operation is realized, the hydraulic cylinder can realize mechanical locking at any position, and the hydraulic cylinder has the advantages of high reliability, difficult influence of environmental change and load and the like, is beneficial to meeting the requirements of equipment on large-angle or long-stroke adjustment and self-locking in a large-gradient or limited space, and meanwhile, due to the interference connection, the hydraulic cylinder is in a locking state in a normal state, even if an external hydraulic pump is damaged in the use process, the hydraulic cylinder can still ensure a stable locking state, and the stability and the safety of the device in the use process can be effectively improved.
Description
Technical Field
The application relates to the field of hydraulic cylinders, in particular to a two-stage expansion cylinder self-locking multi-stage hydraulic cylinder.
Background
The hydraulic cylinder is a hydraulic executive component which can convert hydraulic energy into mechanical energy and do linear reciprocating motion, is widely applied to the fields of engineering machinery, national defense and military industry and the like, and part of the hydraulic cylinder is internally provided with a locking structure due to the requirement of the actual use environment.
The hydraulic cylinder in the prior art realizes the self-locking function by means of a built-in mechanical screw, a steel ball self-locking cylinder or a single-stage cylinder with a locking sleeve and the like, and the modes can realize the self-locking of the hydraulic cylinder, but the modes usually have the defects of different degrees, such as leakage risk of the hydraulic lock or a balance valve, low transmission efficiency of the mechanical screw, single locking position of the steel ball self-locking and the like, so that the flexibility and stability of the self-locking function in the use process of the hydraulic cylinder are difficult to ensure, and the aim of realizing the flexible and stable self-locking of the hydraulic cylinder in a large gradient or a limited space is difficult to meet in special vehicles such as national defense radar vehicles, medical shelter legs and the like.
Therefore, the invention provides a two-stage expansion cylinder self-locking multi-stage hydraulic cylinder to solve some problems in the prior art.
Disclosure of Invention
The application aims to provide a hydraulic cylinder capable of flexibly and stably performing self-locking limiting, compared with the prior art, the hydraulic cylinder comprises a cylinder barrel, a base is fixedly arranged at the bottom of the cylinder barrel, a connecting port a communicated with the bottom of the cylinder barrel is fixedly arranged on the outer end wall of the base, a primary piston rod extending to the outer side of the upper end of the base is vertically inserted into the cylinder barrel, a piston block is fixedly connected to the lower end of the primary piston rod, a primary locking sleeve arranged in the cylinder barrel is fixedly sleeved on the outer side of the lower end of the primary piston rod, a vertically arranged communication hole is formed in the piston block in a penetrating manner, a secondary locking sleeve extending to the outer side of the upper end of the primary piston rod is vertically inserted into the primary piston rod, a sealing ring is arranged at the joint of the primary piston rod, the piston block, the primary locking sleeve and the secondary locking sleeve are in interference connection, an oil duct communicated to the outer end wall of the secondary locking sleeve is vertically arranged on the outer end wall of the secondary locking sleeve, and the unlocking sleeve is fixedly sleeved on the outer end wall of the piston rod a.
Further, the outer end wall of the primary locking sleeve is provided with a drainage groove a which is arranged in a radial surrounding manner, and the outer end wall of the secondary locking sleeve is provided with a drainage groove b which is arranged in a radial surrounding manner.
Further, the drainage groove a and the drainage groove b are both arranged to be of spiral structures, the drainage groove a is directly communicated with the unlocking cannula a, and the drainage groove b is directly communicated with the unlocking oil duct.
Further, the first-stage locking sleeve is internally provided with a cavity corresponding to the drainage groove a in a surrounding mode, and the second-stage locking sleeve is internally provided with a cavity corresponding to the drainage groove b in a surrounding mode.
Further, an unlocking cannula b which penetrates through and is inserted in the unlocking cannula a in a sliding manner is vertically fixed on the base, and a connecting port c which is communicated with the inside of the unlocking cannula b is fixedly arranged on the outer end wall of the base.
Further, be provided with in the piston block and connect the slow accuse subassembly between unblock intubate a and drainage groove a, and slow accuse subassembly is including seting up the valve pocket in the piston block, the intercommunication has passageway a between the top of unblock intubate a and valve pocket, the intercommunication has passageway b between the side end wall of valve pocket and the drainage groove a, the inside top slidable mounting of valve pocket has the valve block, and set up the passageway c that sets up for L shape structure in the valve block, install in the valve pocket and be used for the spring to valve block elastic support, still the intercommunication has passageway d between unblock intubate a and the drainage groove a, and install check valve a in the passageway d.
Further, the lower end of the valve cavity penetrates through the bottom of the piston block, a stud arranged below the valve block is screwed in the valve cavity, and the spring is elastically supported between the valve block and the stud.
Further, a connection port b communicating to the upper inside thereof is fixedly installed on the outer end wall of the cylinder.
Further, an auxiliary oil duct is vertically arranged in the second-stage piston rod, a communication channel communicated with the outer end wall of the second-stage piston rod is arranged in the auxiliary oil duct, the communication channel is tightly attached to the top of the second-stage locking sleeve, an auxiliary insertion pipe a which is inserted in the auxiliary oil duct in a sliding manner is vertically fixed on the piston block, an auxiliary insertion pipe b which is inserted in the auxiliary insertion pipe a in a sliding manner is vertically fixed on the base, and a connection port d communicated with the auxiliary insertion pipe b is fixedly arranged on the outer end wall of the base.
Further, a drainage channel is arranged in the second-stage piston rod, a drainage insertion pipe a inserted in the drainage channel is vertically fixed on the piston block, a drainage insertion pipe b inserted in the drainage insertion pipe a in a sliding manner is vertically fixed on the base, a connection port e communicated with the drainage insertion pipe b is fixedly arranged on the outer end wall of the base, and a one-way valve b is arranged in the communication hole.
Compared with the prior art, the application has the beneficial effects that:
(1) According to the application, the first-stage locking sleeve and the cylinder barrel are connected in an interference manner, the second-stage locking sleeve and the first-stage piston rod are connected in an interference manner, and a gap is formed at the interference connection position after high-pressure oil is supplied, so that unlocking operation is realized, the hydraulic cylinder can realize mechanical locking at any position, and the hydraulic cylinder has the advantages of high reliability, difficulty in being influenced by environmental change and load and the like, and is favorable for realizing large-angle or long-stroke adjustment and self-locking of equipment in a large gradient or limited space.
(2) Through seting up drainage groove a and drainage groove b that spiral structure set up respectively on the outer end wall of one-level lock sleeve and second grade lock sleeve to with unblock intubate a and unblock oil duct respectively direct with drainage groove a and drainage groove b intercommunication, make during the unblock operation, high-pressure oil can fill more smoothly evenly between one-level lock sleeve and cylinder, and between second grade lock sleeve and the one-level piston rod, smooth and easy stability when being favorable to guaranteeing hydraulic cylinder unblock adjustment, simultaneously, drainage groove a and drainage groove b that spiral structure set up can effectively promote the frictional resistance between one-level lock sleeve and the cylinder under the auto-lock state, and the frictional resistance between second grade lock sleeve and the one-level piston rod is favorable to further promoting the stability when this hydraulic cylinder lock.
(3) Through with the cavity encircle offer in the inside of one-level lock sleeve and second grade lock sleeve, can reserve the deformation space of certain degree for the outer end wall of one-level lock sleeve and second grade lock sleeve, avoid because one-level lock sleeve and second grade lock sleeve inner structure are too tight and lead to high pressure oil to be difficult to fill one-level lock sleeve and cylinder and to and between second grade lock sleeve and the one-level piston rod, be favorable to guaranteeing the stability when the device unblock is operated.
(4) Through the unlocking cannula b which is inserted in the unlocking cannula a in a sliding way and is fixedly arranged on the base, and the connecting port c which is communicated with the unlocking cannula b is fixedly arranged on the side end wall of the base, the connecting port c which is used as a high-pressure oil supply inlet is in a relatively stable position, and compared with the connecting port c which is arranged at the upper end of a primary piston rod or a secondary piston rod, the stability of high-pressure oil in the device can be effectively ensured.
(5) Through connecting slowly accuse subassembly between unblock intubate a and drainage groove a, can delay unblock one-level piston rod through slowly accuse subassembly for the unblock of one-level piston rod and second grade piston rod can sectional control, simultaneously, through running through the lower extreme of valve pocket to the bottom of piston block, and shutoff to the valve pocket with the help of screwed connection's double-screw bolt, not only can make things convenient for the staff to change the maintenance to the spring, can also adjust the precompaction dynamics of spring through rotatory double-screw bolt, be favorable to setting for the trigger pressure of high pressure oil when one-level piston rod unblock according to the in-service use demand in the production process, effectively promoted the flexibility in this hydraulic cylinder use.
(6) Through with the connector b fixed mounting that is linked together with the inside one-level lock sleeve top space of cylinder on the top outer end wall of cylinder to offer the auxiliary oil duct that is linked together with the inside two-level lock sleeve top space of one-level piston rod in the second grade piston rod, the intercommunication of cooperation auxiliary intubate a, auxiliary intubate b and connector d makes this hydraulic oil pump when shrink adjustment, can exert the driving force to one-level piston rod and second grade piston rod from the top, simultaneously, derive the hydraulic oil in the space below one-level piston rod inside two-level lock sleeve through being provided with drainage channel, drainage intubate a and drainage intubate b, cooperation check valve b is to the control of the hydraulic oil flow direction in the intercommunicating pore, make alone can not cause the interference to the position of one-level piston rod when controlling the second grade piston rod and shrink adjustment, stability in this hydraulic cylinder use has been ensured.
Drawings
FIG. 1 is a perspective view of the present application;
FIG. 2 is a top view of the present application;
FIG. 3 is a cross-sectional view of the structure of FIG. 2 at A-A in accordance with the present application;
FIG. 4 is a schematic diagram of the structure of FIG. 3D according to the present application;
FIG. 5 is a cross-sectional view of the structure of FIG. 2 at B-B in accordance with the present application;
FIG. 6 is a schematic diagram of the structure of FIG. 5E in accordance with the present application;
FIG. 7 is a cross-sectional view of the structure of FIG. 2 at C-C in accordance with the present application;
FIG. 8 is a schematic illustration of the structure of FIG. 7 at F in accordance with the present application;
FIG. 9 is a perspective view of the primary piston rod, piston block and primary locking sleeve of the present application;
Fig. 10 is a structural perspective view of the secondary piston rod and the secondary locking sleeve of the present application.
The reference numerals in the figures illustrate:
1. A cylinder; 101. a base; 102. a connection port a; 103. a connection port b; 2. a first-stage piston rod; 201. a piston block; 202. a first-stage locking sleeve; 203. a communication hole; 3. a second-stage piston rod; 301. a second-stage locking sleeve; 4. a seal ring; 5. unlocking the oil duct; 501. unlocking the cannula a; 502. drainage groove a; 503. drainage groove b; 504. a cavity; 505. unlocking the cannula b; 506. a connection port c; 6. a valve cavity; 601. a channel a; 602. a channel b; 603. a valve block; 604. a channel c; 605. a spring; 606. a channel d; 607. a one-way valve a; 608. a stud; 7. an auxiliary oil passage; 701. a connecting channel; 702. an auxiliary cannula a; 703. an auxiliary cannula b; 704. a connection port d; 705. a flow leakage path; 706. a drainage cannula a; 707. a drainage cannula b; 708. a connection port e; 709. a one-way valve b.
Detailed Description
The embodiments of the present application will be described in detail and fully with reference to the accompanying drawings, and it is intended that all other embodiments of the application, which are apparent to one skilled in the art without the inventive faculty, are included in the scope of the present application.
Examples
The invention provides a two-stage expansion cylinder self-locking multistage hydraulic cylinder, referring to fig. 1-10, which comprises a cylinder barrel 1, wherein a base 101 is fixedly arranged at the bottom of the cylinder barrel 1, a connecting port a102 communicated with the bottom of the cylinder barrel 1 is fixedly arranged on the outer end wall of the base 101, a first-stage piston rod 2 extending to the outer side of the upper end of the base is vertically inserted in the cylinder barrel 1, the lower end of the first-stage piston rod 2 is fixedly connected with a piston block 201, a first-stage locking sleeve 202 arranged in the cylinder barrel 1 is fixedly sleeved on the outer side of the lower end of the first-stage piston rod 2, a vertically arranged communication hole 203 is formed in the piston block 201 in a penetrating manner, a second-stage piston rod 3 extending to the outer side of the upper end of the first-stage piston rod 2 is vertically inserted in the first-stage piston rod 2, a second-stage locking sleeve 301 arranged in a penetrating manner in the outer side of the lower end of the second-stage piston rod 3 is fixedly sleeved on the outer side of the second-stage piston rod 3, sealing rings 4 are respectively arranged at the connecting positions of the cylinder barrel 1, the first-stage locking sleeve 202, the second-stage piston rod 3 and the second-stage locking sleeve 301 are connected with the cylinder barrel 1, the second-stage locking sleeve 202 is in a connecting manner, the second-stage locking sleeve 301 is in interference fit between the second-stage locking sleeve 301 and the piston rod 2, the second-stage locking sleeve 3 is fixedly connected with the piston rod 2, the first-stage locking sleeve is provided with a piston rod 501, the second-stage locking sleeve is provided with a release sleeve, the second-stage locking sleeve is arranged on the end and the end of the unlocking sleeve, and the unlocking sleeve is connected with the unlocking sleeve, and the unlocking sleeve is arranged on the end, and the end of the piston rod is a5, and the lock sleeve is mounted on the end, and the lock sleeve, and the release sleeve is mounted.
During the use of the hydraulic cylinder, a worker connects the hydraulic cylinder, the hydraulic pump controls the hydraulic oil in the hydraulic cylinder to flow, starting of the hydraulic cylinder is achieved, the whole hydraulic cylinder is in a contracted state in an initial state, the primary piston rod 2 is contracted in the cylinder 1, the secondary piston rod 3 is contracted in the primary piston rod 2, due to the interference connection between the primary locking sleeve 202 and the cylinder 1, the secondary locking sleeve 301 is in interference connection with the primary piston rod 2, the outer end wall of the primary locking sleeve 202 is tightly attached to the inner end wall of the cylinder 1, the outer end wall of the secondary locking sleeve 301 is tightly attached to the inner end wall of the primary piston rod 2, under the condition of too tight contact, the primary locking sleeve 202 cannot slide in the cylinder 1 under the condition of too tight contact, likewise, the secondary locking sleeve 301 cannot slide in the cylinder 2, at the moment, the hydraulic cylinder is in a self-locking state, when the self-locking state of the hydraulic cylinder needs to be relieved, the worker only needs to control the injection of high-pressure oil into the unlocking sleeve 5, the high-pressure oil flows through the outer end wall of the secondary locking sleeve 301, the upper end wall and the lower end wall of the secondary locking sleeve 301 are tightly attached to the outer end wall of the secondary locking sleeve 301, the lower end wall of the secondary locking sleeve 301 is attached to the inner end wall of the cylinder 4 is attached to the inner end wall of the cylinder 2, the high-pressure oil duct 301 is continuously between the secondary locking sleeve 301 and the piston rod 2 is prevented from being attached to the piston rod 2, and the high-level locking sleeve is continuously, and the friction resistance between the two-level locking sleeve 2 is reduced, and the two-level locking sleeve is kept between the two-side and the inner side locking sleeve is kept in a large friction resistance between the two side and the piston rod 2 is kept in a large amplitude between the friction between the upper and the inner side and the sealing sleeve 2 is.
Similarly, the high-pressure oil injected into the unlocking oil duct 5 also flows into the unlocking cannula a501, flows onto the outer end wall of the primary locking sleeve 202 through the unlocking cannula a501, and because the sealing rings 4 are also installed on the upper side and the lower side of the outer end wall of the primary locking sleeve 202, the high-pressure oil flowing into the unlocking oil duct is also limited between the upper sealing ring 4 and the lower sealing ring 4 of the outer end wall of the primary locking sleeve 202, and the interference fit between the primary locking sleeve 202 and the cylinder 1 is spread along with continuous injection of the high-pressure oil to form a gap, so that the friction resistance between the primary locking sleeve 202 and the cylinder 1 is greatly weakened, the primary locking sleeve 202 can slide up and down in the cylinder 1, and the primary piston rod 2 is not in a locked state any more.
After the locking state of the first-stage piston rod 2 and the second-stage piston rod 3 is released, a worker controls an external hydraulic pump to inject hydraulic oil into the cylinder barrel 1 through the connection port a102, because of the communication hole 203, the hydraulic oil is sequentially injected into the space below the first-stage locking sleeve 202 inside the cylinder barrel 1 and the space below the second-stage locking sleeve 301 inside the first-stage piston rod 2, and along with the injection of the hydraulic oil, the first-stage piston rod 2 and the second-stage piston rod 3 are sequentially jacked upwards to realize the expansion of the hydraulic oil, otherwise, the worker can control the hydraulic pump to suck the hydraulic oil filled in the cylinder barrel 1 and the first-stage piston rod 2, so that the second-stage piston rod 3 is gradually retracted into the first-stage piston rod 2, and the first-stage piston rod 2 is gradually retracted into the cylinder barrel 1, thereby realizing the contraction control of the hydraulic oil cylinder.
When the hydraulic cylinder is subjected to telescopic adjustment, the external hydraulic pump is used for carrying out pressure maintaining operation on the output of high-pressure oil, so that in the telescopic adjustment process, the space between the first-stage locking sleeve 202 and the cylinder barrel 1, the space between the second-stage locking sleeve 301 and the first-stage piston rod 2 are kept in an expanded state, after the telescopic adjustment of the hydraulic cylinder is completed, a worker interrupts the supply of the high-pressure oil in the unlocking oil duct 5 and does not carry out pressure maintaining operation in the unlocking oil duct, at the moment, the continuous supply of the subsequent high-pressure oil is lost, the space between the first-stage locking sleeve 202 and the cylinder barrel 1, the space between the second-stage locking sleeve 301 and the first-stage piston rod 2 are elastically deformed to restore to an initial state, the high-pressure oil filled between the first-stage locking sleeve 202 and the cylinder barrel 1, the space between the second-stage locking sleeve 301 and the first-stage piston rod 2 is extruded, and the second-stage locking sleeve 301 is restored to an interference fit state, and the self-locking of the first-stage piston rod 2 and the second-stage piston rod 3 is realized after adjustment.
In the use process of the hydraulic oil cylinder, the primary piston rod 2 and the secondary piston rod 3 which are sequentially inserted in the cylinder barrel 1 can be subjected to multistage expansion, so that the whole space occupation amount is small when the hydraulic oil cylinder is contracted, and a longer stroke can be obtained when the hydraulic oil cylinder is expanded, meanwhile, through setting interference connection between the primary locking sleeve 202 and the cylinder barrel 1 and between the secondary locking sleeve 301 and the primary piston rod 2, self-locking of the hydraulic oil cylinder under normal state is realized, a gap is formed at the position of interference fit after high-pressure oil is matched for feeding, unlocking operation is realized, the hydraulic oil cylinder can not only greatly lift axial load, but also realize mechanical locking at any position in the use process, the hydraulic oil cylinder is locked in a mechanical mode, the reliability is high, the hydraulic oil cylinder is not easily influenced by environmental change and load, and the hydraulic oil cylinder is favorable for realizing adjustment and self-locking of large angles or long strokes in large gradient or limited space.
Because the hydraulic oil cylinder is in a locking state in normal state, the unlocking can be carried out only after the high-pressure oil is filled, so that the hydraulic oil cylinder is automatically in locking after the high-pressure oil is supplied and interrupted, even if the hydraulic pump is damaged in the use process and can not continuously fill hydraulic oil, the hydraulic oil cylinder can still ensure a stable locking state, can not retract instantaneously due to the error of the hydraulic oil supply, and can effectively promote the stable safety of the device in the use process.
Referring to fig. 4, 9 and 10, a drainage groove a502 is formed on the outer end wall of the primary locking sleeve 202, a drainage groove b503 is formed on the outer end wall of the secondary locking sleeve 301, the drainage groove a502 and the drainage groove b503 are both in spiral structures, the drainage groove a502 is directly communicated with the unlocking cannula a501, the drainage groove b503 is directly communicated with the unlocking oil duct 5, during the use process of the hydraulic cylinder, the drainage groove a502 is positioned between the sealing rings 4 on the upper side and the lower side of the outer end wall of the primary locking sleeve 202, the drainage groove b503 is positioned between the sealing rings 4 on the upper side and the lower side of the outer end wall of the secondary locking sleeve 301, as the drainage groove a502 and the drainage groove b503 are both in spiral structures, and the drainage groove a502 is directly communicated with the unlocking cannula a501, the drainage groove b503 is directly communicated with the unlocking oil duct 5, this makes the high-pressure oil in unblock oil duct 5 and the unblock intubate a501 when filling between one-level lock sleeve 202 and cylinder 1, between second grade lock sleeve 301 and one-level piston rod 2, can flow along helical structure's drainage groove a502, drainage groove b503, under the guide of drainage groove a502 and drainage groove b503, make the high-pressure oil fully and evenly fill between one-level lock sleeve 202 and cylinder 1, and between second grade lock sleeve 301 and one-level piston rod 2, under the continuous filling of high-pressure oil, between one-level lock sleeve 202 and cylinder 1, between second grade lock sleeve 301 and one-level piston rod 2 can be evenly propped open, and the separation is thoroughly, the frictional resistance that receives when one-level lock sleeve 202 and second grade lock sleeve 301 slide under the unblock state effectively reduced, thereby the smoothness of adjustment under this hydro-cylinder unblock state has effectively been ensured.
Meanwhile, as the drainage groove a502 and the drainage groove b503 are respectively arranged on the outer end walls of the primary locking sleeve 202 and the secondary locking sleeve 301 in a surrounding mode in a spiral mode, grooves which are arranged in a radial mode are formed in the outer end walls of the primary locking sleeve 202 and the secondary locking sleeve 301, roughness of the outer end walls of the primary locking sleeve 202 and the secondary locking sleeve 301 is greatly improved, when the primary locking sleeve 202 is in interference fit with the cylinder barrel 1, friction resistance between the primary locking sleeve 202 and the cylinder barrel 1 can be greatly improved due to the existence of the drainage groove a502, when the secondary locking sleeve 301 is in interference fit with the primary piston rod 2, friction resistance between the secondary locking sleeve 301 and the primary piston rod 2 can be greatly improved due to the existence of the drainage groove b503, and stability of the hydraulic cylinder in a locking state is further improved.
Referring to fig. 4, the cavity 504 corresponding to the drainage groove a502 is formed in the primary locking sleeve 202 in a surrounding manner, the cavity 504 corresponding to the drainage groove b503 is formed in the secondary locking sleeve 301 in a surrounding manner, the unlocking cannula b505 inserted in the unlocking cannula a501 in a penetrating manner is vertically fixed on the base 101, the connecting port c506 communicated with the inside of the unlocking cannula b505 is fixedly mounted on the outer end wall of the base 101, in the using process of the hydraulic cylinder, the space can be reserved for elastic deformation of the primary locking sleeve 202 and the outer end wall of the secondary locking sleeve 301 by surrounding manner, the space can be reserved for the elastic deformation of the primary locking sleeve 202 and the outer end wall of the secondary locking sleeve 301, the primary locking sleeve 202 and the cylinder barrel 1 are avoided, the secondary locking sleeve 301 and the primary piston rod 2 are in interference fit too tight to be charged and separated by high-pressure oil, stability during unlocking of the hydraulic cylinder is guaranteed, meanwhile, the unlocking cannula b505 is inserted in the unlocking cannula a501 in a sliding manner, the connecting port c506 communicated with the unlocking cannula a501 is fixedly mounted on the outer end wall of the base 101, and a worker can move to the connecting port c506 through the connecting port c506 to the high-pressure oil channel 5, and can be supplied to the high-pressure oil channel or the high-pressure oil channel can be arranged on the base 101 in a position which can be fixed relatively, compared with the high-pressure oil channel is fixed to the high-pressure oil channel, and the high-pressure oil can be stably arranged at the position of the piston rod 2.
Referring to fig. 4 and 8, a buffer control assembly connected between an unlocking cannula a501 and a drainage groove a502 is arranged in a piston block 201, the buffer control assembly comprises a valve cavity 6 arranged in the piston block 201, a channel a601 is communicated between the unlocking cannula a501 and the top end of the valve cavity 6, a channel b602 is communicated between the side end wall of the valve cavity 6 and the drainage groove a502, a valve block 603 is slidably arranged above the valve cavity 6, a channel c604 which is arranged in an L-shaped structure is arranged in the valve block 603, a spring 605 which is used for elastically supporting the valve block 603 is arranged in the valve cavity 6, a channel d606 is also communicated between the unlocking cannula a501 and the drainage groove a502, a one-way valve a607 is arranged in the channel d606, the lower end of the valve cavity 6 penetrates to the bottom of the piston block 201, a stud 608 arranged below the valve block 603 is screwed inside the valve cavity 6, and the spring 605 is elastically supported between the valve block 603 and the stud 608.
During the use of the hydraulic cylinder, whether the locking of the first-stage piston rod 2 is released can be selected according to actual operation requirements, when the unlocking operation is carried out, staff continuously injects high-pressure oil into the unlocking cannula a501 and the unlocking oil duct 5 through the connecting port c506 and the unlocking cannula b505, a slow control component is connected between the unlocking cannula a501 and the drainage groove a502, a valve block 603 arranged between the channel a601 and the channel b602 is arranged in the slow control component, the force overcome by the compression spring 605 of the high-pressure oil pushing valve block 603 is larger than the force overcome by the compression spring 605 of the high-pressure oil filled between the second-stage locking sleeve 301 and the first-stage piston rod 2, the high-pressure oil can be filled between the second-stage locking sleeve 301 and the first-stage piston rod 2 firstly in the continuous filling process of the high-pressure oil, the high-pressure oil can not enter due to the blocking of the slow control component between the first-stage locking sleeve 202 and the cylinder 1, the high-pressure oil can not fill between the outer end wall of the second-stage locking sleeve 301 and the inner end wall of the first-stage piston rod 2 at the moment, the smooth sliding gap is formed by separation, the second-stage 3 is in the unlocking state, the high-pressure oil can not be filled between the first-stage locking sleeve 202 and the first-stage piston rod 2, the high-pressure oil can not be normally adjusted, and the telescopic piston rod 2 can not be in the normal state.
When the primary piston rod 2 and the secondary piston rod 3 need to be simultaneously unlocked, under the condition that high-pressure oil is filled between the secondary locking sleeve 301 and the primary piston rod 2, the filling force of the high-pressure oil is continuously increased, the filling force of the high-pressure oil is lifted, the upper part of the valve block 603 is acted on by the channel a601, the elastic support of the spring 605 is compressed, the other end of the channel c604 is aligned with the channel b602 after the valve block 603 moves downwards, the channel c604 is communicated between the channel a601 and the channel b602 in the state, continuously filled high-pressure oil enters the space above the valve block 603 in the valve cavity 6 through the channel a601, then enters the channel b602 through the channel c604, finally enters the drainage groove a502, the primary locking sleeve 202 and the cylinder 1 are unfolded to perform unlocking operation, when the re-locking is needed, the continuous supply of the high-pressure oil is interrupted, at the moment, the upper part of the spring 605 loses enough driving force, the connection between the channel a601 and the channel b602 is in an interruption state again, the high-pressure oil filled between the primary locking sleeve 202 and the cylinder 1 is in the high-pressure oil state through the channel d 607 and the channel d606, the high-pressure oil can not enter the one-way locking sleeve 202 a and the one-way valve rod 2 through the channel d606, the one-way locking sleeve 501 can not be controlled, the one-way locking sleeve is arranged in the channel 1, the one-way locking sleeve is unlocked, and the high-way locking sleeve is only can be controlled, and the high-way locking sleeve 501 can be opened, and can not be unlocked, and can be opened, and can be unlocked by the one-way, and can be opened by the high-speed, and can be easily and stably, and easily unlocked, and easily,.
Through running through the lower extreme of valve pocket 6 to the bottom of piston piece 201 to shutoff with the help of screwed connection's double-screw bolt 608, not only can make things convenient for spring 605 to change and maintain, can also adjust the precompaction dynamics of spring 605 through the position of rotatory adjusting the double-screw bolt 608, can be according to the triggering pressure of the high-pressure oil when the flexible adjustment one-level piston rod 2 unblock of actual use demand, promoted the flexibility in this hydraulic cylinder use to a certain extent.
Referring to fig. 4 and 6, a connection port b103 connected to the upper part of the inside of the cylinder barrel 1 is fixedly installed on the outer end wall of the cylinder barrel 1, an auxiliary oil duct 7 is vertically arranged in the secondary piston rod 3, a communication channel 701 communicated with the outer end wall of the secondary piston rod 3 is vertically arranged in the auxiliary oil duct 7, the communication channel 701 is closely attached to the top of the secondary locking sleeve 301, an auxiliary cannula a702 which is slidably inserted in the auxiliary oil duct 7 is vertically fixed on the piston block 201, an auxiliary cannula b703 which is slidably inserted in the auxiliary cannula a702 is vertically fixed on the base 101, a connection port d704 communicated with the auxiliary cannula b703 is fixedly installed on the outer end wall of the base 101, a drainage channel 705 is arranged in the secondary piston rod 3, a drainage cannula a 707 inserted in the drainage channel 705 is vertically fixed on the piston block 201, a connection port e708 communicated with the drainage cannula b is fixedly installed on the outer end wall of the base 101, and a one-way valve b709 is installed in the communication hole 203.
In the use process of the hydraulic cylinder, if the contraction control is realized only through the suction of an external hydraulic pump, the contraction of the hydraulic cylinder is easily unstable, and the contraction force is easily insufficient, therefore, the connecting port b103 is arranged at the upper position of the outer end wall of the cylinder barrel 1 and is communicated with the space above the primary locking sleeve 202 inside the cylinder barrel 1, when the retraction operation of the primary piston rod 2 is required, a worker can realize the retraction operation of the hydraulic cylinder by pumping hydraulic oil at the bottom of the cylinder barrel 1 through the hydraulic pump, can also connect another group of hydraulic pumps, and the injection of hydraulic oil is carried out in the space above the primary locking sleeve 202 in the cylinder barrel 1 through the connecting port b103, so that the primary locking sleeve 202 is pushed from top to bottom, and the contraction control of the primary piston rod 2 is realized.
Similarly, by vertically opening the auxiliary oil passage 7 communicating with the space above the secondary lock sleeve 301 inside the primary piston rod 2 in the secondary piston rod 3 and slidably inserting the auxiliary insertion tube a702 fixed to the piston block 201 in the auxiliary oil passage 7 and slidably inserting the auxiliary insertion tube b703 fixed to the base 101 in the auxiliary insertion tube a702, a worker can perform injection of hydraulic oil into the space above the secondary lock sleeve 301 inside the primary piston rod 2 through the connection port d704, when the secondary piston rod 3 is retracted, the driving force is actively applied to the secondary piston rod 3 from above, since the check valve b709 is fixedly installed in the communication hole 203, hydraulic oil can only enter the primary piston rod 2 from inside the cylinder 1 through the communication hole 203, hydraulic oil in the space below the secondary lock sleeve 301 in the primary piston rod 2 cannot flow back into the space below the primary lock sleeve 202 through the communication hole 203, so that when the secondary piston rod 3 is retracted alone, hydraulic oil in the space below the secondary lock sleeve 301 in the primary piston rod 2 enters into the drain passage 705 from below under the extrusion action, and then enters the connection port d 706, the expansion and contraction of the hydraulic oil cylinder 2 cannot be regulated independently, and the expansion and contraction of the piston rod 3 cannot be disturbed, and the expansion of the piston rod 2 can be regulated independently, and the expansion and contraction position of the piston rod 3 can be regulated.
The present application is not limited to the preferred embodiments described above, but is merely preferred for practical application.
Claims (6)
1. The utility model provides a two-stage expansion cylinder auto-lock multistage hydraulic cylinder, includes cylinder (1), its characterized in that, the bottom fixed mounting of cylinder (1) has base (101), fixed mounting has connector a (102) that is linked together with cylinder (1) bottom on the outer end wall of base (101), the vertical one-level piston rod (2) that run through and extend to its upper end outside that insert in cylinder (1), and the lower extreme fixedly connected with piston block (201) of one-level piston rod (2), one-level lock sleeve (202) that set up in cylinder (1) are fixed to the lower extreme outside of one-level piston rod (2), run through in piston block (201) and set up communication hole (203) of vertical setting, the vertical two-level piston rod (3) that run through and extend to its upper end outside that insert in one-level piston rod (2), and two-level piston rod (2) are fixed to be sleeved with in the lower extreme outside of two-level piston rod (3), cylinder (1), one-level piston rod (201), two-level lock sleeve (202) and two-level lock sleeve (301) are all connected between one-level lock sleeve (2) and the connection between one-level lock sleeve (2), an unlocking oil duct (5) communicated to the outer end wall of the secondary locking sleeve (301) is vertically arranged in the secondary piston rod (3), an unlocking insertion pipe a (501) which is inserted in the unlocking oil duct (5) in a sliding manner is fixedly arranged on the piston block (201), and the unlocking insertion pipe a (501) is communicated to the outer end wall of the primary locking sleeve (202);
The novel anti-theft lock is characterized in that a drainage groove a (502) which is arranged in a radial surrounding mode is formed in the outer end wall of the primary locking sleeve (202), a drainage groove b (503) which is arranged in a radial surrounding mode is formed in the outer end wall of the secondary locking sleeve (301), a buffering control component which is connected between an unlocking insertion tube a (501) and the drainage groove a (502) is arranged in the piston block (201), the buffering control component comprises a valve cavity (6) which is formed in the piston block (201), a channel a (601) is communicated between the unlocking insertion tube a (501) and the top end of the valve cavity (6), a channel b (602) is communicated between the side end wall of the valve cavity (6) and the drainage groove a (502), a valve block (603) is slidably arranged above the valve cavity (6), a channel c (604) which is arranged in an L-shaped structure is formed in the valve cavity (6), a spring (605) which is used for elastically supporting the valve block (603) is arranged in the valve cavity (6), a channel d (607) is communicated between the unlocking insertion tube a (501) and the top of the valve cavity (502), and a channel d (606) is arranged in the channel d (606);
An auxiliary oil duct (7) is vertically arranged in the secondary piston rod (3), a communication channel (701) communicated with the outer end wall of the secondary piston rod (3) is arranged in the auxiliary oil duct (7), the communication channel (701) is closely attached to the top of the secondary locking sleeve (301), an auxiliary cannula a (702) which is slidably inserted in the auxiliary oil duct (7) is vertically fixed on the piston block (201), an auxiliary cannula b (703) which is slidably inserted in the auxiliary cannula a (702) is vertically fixed on the base (101), a connecting port d (704) communicated with the auxiliary cannula b (703) is fixedly arranged on the outer end wall of the base (101), a leakage flow channel (705) is arranged in the secondary piston rod (3), a leakage cannula a (706) which is inserted in the leakage flow channel (705) is vertically fixed on the piston block (201), a leakage cannula b (707) which is slidably inserted in the leakage cannula a (706) is vertically fixed on the base (101), and a connecting port d (708) is fixedly arranged on the outer end wall of the base (101) and is fixedly connected with a connecting port e (709).
2. The two-stage expansion cylinder self-locking multistage hydraulic cylinder according to claim 1, wherein the drainage groove a (502) and the drainage groove b (503) are both in spiral structures, the drainage groove a (502) is directly communicated with the unlocking cannula a (501), and the drainage groove b (503) is directly communicated with the unlocking oil duct (5).
3. The two-stage expansion cylinder self-locking multistage hydraulic cylinder according to claim 2, wherein a cavity (504) corresponding to the drainage groove a (502) is formed in the primary locking sleeve (202) in a surrounding mode, and a cavity (504) corresponding to the drainage groove b (503) is formed in the secondary locking sleeve (301) in a surrounding mode.
4. The two-stage expansion cylinder self-locking multistage hydraulic cylinder according to claim 1, wherein an unlocking cannula b (505) inserted in the unlocking cannula a (501) in a penetrating and sliding manner is vertically fixed on the base (101), and a connecting port c (506) communicated with the inside of the unlocking cannula b (505) is fixedly installed on the outer end wall of the base (101).
5. The two-stage expansion cylinder self-locking multistage hydraulic cylinder according to claim 1, wherein the lower end of the valve cavity (6) penetrates to the bottom of the piston block (201), a stud (608) arranged below the valve block (603) is screwed inside the valve cavity (6), and the spring (605) is elastically supported between the valve block (603) and the stud (608).
6. The two-stage expansion cylinder self-locking multistage hydraulic cylinder according to claim 1, wherein a connecting port b (103) communicated to the upper part inside the cylinder barrel (1) is fixedly arranged on the outer end wall of the cylinder barrel.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN101392775A (en) * | 2007-09-17 | 2009-03-25 | 北京航天发射技术研究所 | Two stage interference lock fastening hydraulic cylinder at optional position |
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| US5680808A (en) * | 1996-05-09 | 1997-10-28 | Ingersoll-Rand Company | Fluid cylinder and method of assembly |
| CN104776085B (en) * | 2015-04-02 | 2016-10-26 | 中船重工中南装备有限责任公司 | The strength mechanical self-locking hydraulic cylinder of band buffering |
| CN107401533B (en) * | 2017-08-08 | 2023-05-16 | 华南理工大学 | End-control type internal expansion mechanical locking hydraulic cylinder and operation method thereof |
| CN111075388B (en) * | 2020-02-10 | 2024-04-19 | 山东博赛特石油技术有限公司 | Hydraulic releasing packer and method for preventing midway setting |
| CN214661227U (en) * | 2021-05-11 | 2021-11-09 | 上海欣源液压设备成套有限公司 | Self-locking multistage hydraulic telescopic rod mechanism |
| CN117623186A (en) * | 2023-11-21 | 2024-03-01 | 北京航天发射技术研究所 | Lifting device based on locking sleeve hydraulic cylinder and control system and method thereof |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN101392775A (en) * | 2007-09-17 | 2009-03-25 | 北京航天发射技术研究所 | Two stage interference lock fastening hydraulic cylinder at optional position |
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