CN106678125B - A kind of oil cylinder of hydraulic headstock gear buffer unit and operating method - Google Patents

A kind of oil cylinder of hydraulic headstock gear buffer unit and operating method Download PDF

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Publication number
CN106678125B
CN106678125B CN201611104738.8A CN201611104738A CN106678125B CN 106678125 B CN106678125 B CN 106678125B CN 201611104738 A CN201611104738 A CN 201611104738A CN 106678125 B CN106678125 B CN 106678125B
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China
Prior art keywords
restricting orifice
hydraulic
lower cover
piston rod
annular groove
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CN201611104738.8A
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CN106678125A (en
Inventor
万兴余
郭明
常征
靳晓雷
杜浩斌
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CSIC Zhongnan Equipment Co Ltd
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CSIC Zhongnan Equipment Co Ltd
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B15/00Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
    • F15B15/20Other details, e.g. assembly with regulating devices
    • F15B15/22Other details, e.g. assembly with regulating devices for accelerating or decelerating the stroke
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B15/00Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
    • F15B15/08Characterised by the construction of the motor unit
    • F15B15/14Characterised by the construction of the motor unit of the straight-cylinder type
    • F15B15/1423Component parts; Constructional details
    • F15B15/1433End caps
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B15/00Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
    • F15B15/08Characterised by the construction of the motor unit
    • F15B15/14Characterised by the construction of the motor unit of the straight-cylinder type
    • F15B15/1423Component parts; Constructional details
    • F15B15/1457Piston rods

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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 present invention relates to a kind of oil cylinder of hydraulic headstock gear buffer unit and operating method, it includes cylinder body, the cylinder interior, which is slidably installed, load-bearing piston, the inside of the load-bearing piston is installed with piston rod, half piston and cushion collar is fixedly mounted in one end that the piston rod is located at cylinder interior, one end of the cylinder body is provided with lower cover, one end that the lower cover is located at cylinder interior is machined with annular groove, the annular groove mounted inside has restricting orifice, the restricting orifice is encapsulated in inside annular groove by gland, the outer face of the lower cover is provided with sealing gland and scraping dirt circle, the sealing gland and scraping dirt circle are engaged with the outer wall of piston rod.This buffer unit is easy to process, and can be easily fitted into rapid door hydraulic headstock gear, reaches good buffer effect when closing, small to the obstruction of hydraulic oil when opening, does not increase and opens a pressure, has little influence on potted component and hydraulic system service life.

Description

A kind of oil cylinder of hydraulic headstock gear buffer unit and operating method
Technical field
The present invention relates to field of water conservancy, buffered when being closed for rapid operation gate hydraulic headstock gear, prevent gate Excessive velocities caused large impact when reaching bottom bank.
Background technology
During water conservancy construction is carried out, such as when building ship lock or building natural flow station, rapid operation is often used Gate and the rapid door hydraulic headstock gear opened and closed to gate.The effect of rapid operation gate be when an emergency happens, Gate can fall closing current rapidly, try to avert accidents.Therefore, the closing speed of rapid door hydraulic headstock gear is very fast, such as Fruit does not set buffer unit in oil cylinder of hydraulic headstock gear, can be to gate sill and keying when falling on end of travel under gate Machine lower cover causes greater impact.At this stage, the form of buffer unit is relatively more, has and sets one-way throttle valve, has and utilize overflow Valve, have annulus throttle, etc..But these devices are mostly all more complicated, some are also higher to processing request, Reduce the stability and reliability of buffer unit.Some currently used buffer units, still another shortcoming is that at closing time Buffering effect is preferable, but during door is opened, buffer unit is larger to the inhibition of high-voltage oil liquid so that opens when starting A period of time in, open a pressure and be higher than service pressure, sometimes even up to several MPa, influence potted component and hydraulic pressure The service life of system.Some other buffer units, dismounting and maintenance are all inconvenient, and part of the present invention is few, and dismounting and maintenance are all It is very convenient.
The content of the invention
Present invention solves the technical problem that be to provide it is a kind of by restricting orifice with buffering set group into buffer unit and operation Method, this buffer unit is easy to process, and can be easily fitted into rapid door hydraulic headstock gear, reaches and is buffered when closing Effect is good, small to the obstruction of hydraulic oil when opening, does not increase and opens a pressure, has little influence on potted component and hydraulic system uses Life-span.
In order to solve the above-mentioned technical problem, the present invention proposes following technical scheme:A kind of oil cylinder of hydraulic headstock gear buffering dress Put, it includes cylinder body, and the cylinder interior, which is slidably installed, load-bearing piston, and the inside of the load-bearing piston is installed with Half piston and cushion collar, one end installation of the cylinder body is fixedly mounted in piston rod, one end that the piston rod is located at cylinder interior There is lower cover, one end that the lower cover is located at cylinder interior is machined with annular groove, and the annular groove mounted inside has restricting orifice, institute State restricting orifice to be encapsulated in inside annular groove by gland, the outer face of the lower cover is provided with sealing gland and scraping dirt circle, institute State sealing gland and scraping dirt circle is engaged with the outer wall of piston rod.
The groove width of the lower cover internal annular groove is more than the thickness of restricting orifice, can ensure that restricting orifice is put into annular groove Afterwards, can be along piston rod slidably.
The edge of the restricting orifice is along the circumferential direction uniformly machined with multiple through holes;The restricting orifice matches with gland The end face of conjunction is machined with annular protrusion, can ensure that the end face that through hole is not glanded is blocked, the restricting orifice and lower cover The end face that annular groove step surface is engaged is plane, can ensure that lower cover blocks to the through hole of restricting orifice.
The centre bore of the cushion collar and restricting orifice is coordinated using gap, can ensure that fluid circulates from fit clearance.
The length of the cushion collar has a variety of different specifications, to adapt to the requirement of different cushion strokes.
Using the operating method of any one oil cylinder of hydraulic headstock gear buffer unit:
Before buffering starts, cushion collar follows piston rod quickly to move together, and now cushion collar is located at cylinder interior and do not risen Acted on to any damping buffering, hydraulic oil promotes piston rod quickly to move so that stop gate can fall rapidly, quick closedown Current;
In buffer stage, when stop gate reaches end of travel, when will reach gate sill, cushion collar right-hand member is inserted first Enter in restricting orifice, the cross-sectional flow area moment of hydraulic oil reduces, and the hydraulic fluid pressure rise on the left of restricting orifice, promotes throttling Orifice plate is moved right, and restricting orifice is compressed tightly against on the step of lower cover so that annular is uniform on restricting orifice 16 are logical Hole is closed, and hydraulic oil can only flow to oil by the annulus that the external diameter of cushion collar and the internal diameter of restricting orifice are formed Case, the effect of annulus throttling is served, makes the speed of rapid door reduce rapidly, finally gently falls on gate sill, Current are thoroughly closed, avoid the percussion to bottom bank;
In quick open stage, when emergency is released, it is necessary to when opening gate, oil cylinder piston is now high to left movement Press oil liquid to flow into from hydraulic fluid port, be partly into the right chamber of cushion collar, a part enters a cushion collar left side by restricting orifice In the chamber of side, Qi Menshi, the hydraulic fluid pressure on the right side of restricting orifice promotes section higher than the pressure on the left of restricting orifice, hydraulic oil Discharge orifice plate is to left movement so that the annular protrusion on the left of restricting orifice is close on gland, makes shape between gland and restricting orifice The gap very big into one, the hydraulic oil that hydraulic fluid port enters can enter restricting orifice by 16 uniform through holes of restricting orifice Left side, high-voltage oil liquid is swimmingly flowed through, almost without the pressure loss, gate can be made quickly to open and avoid and open a pressure Rise, avoid having an impact the life-span of potted component.
Beneficial effects of the present invention:
1st, by installing cushion collar on the piston rod, can be played very well by the cooperation between cushion collar and restricting orifice Throttling buffering effect, during avoiding fast opening and closing gate, impact of the gate to gate sill.
2nd, by the annular groove that restricting orifice is slidably installed inside cylinder body 1, the two of restricting orifice can be ensured End face forms cooperation respectively with the end face of gland and the interior step surface of lower cover respectively, so realize closure oil circuit and open oil circuit it Between automatic switching function, the function of realizing throttling buffering and quickly open.
3rd, buffer structure of the invention is simple, easy for installation, and parts machining manufacturing process is simple, and reliability is high, Damage to hydraulic system hermetic devices is small, extends its service life.
Brief description of the drawings
The invention will be further described with reference to the accompanying drawings and examples.
Fig. 1 is that present invention buffering starts pre-structure schematic diagram.
Fig. 2 is buffer stage figure of the present invention.
Fig. 3 is that the present invention opens a stage diagram.
Fig. 4 is the restricting orifice figure of the present invention.
Fig. 5 is the Section A-A figure of restricting orifice figure in Fig. 4 of the invention.
Fig. 6 is the restricting orifice stereogram of the present invention.
In figure:Cylinder body 1, load-bearing piston 2, half piston 3, cushion collar 4, gland 5, restricting orifice 6, lower cover 7, sealing gland 8, Scraping dirt circle 9, piston rod 10;
Through hole 601, annular protrusion 602.
Embodiment
Embodiments of the present invention are described further below in conjunction with the accompanying drawings.
Embodiment 1:
Such as Fig. 1-5, a kind of oil cylinder of hydraulic headstock gear buffer unit, it includes cylinder body 1, the sliding fit inside of cylinder body 1 Load-bearing piston 2 is installed, the inside of the load-bearing piston 2 is installed with piston rod 10, and the piston rod 10 is located in cylinder body 1 Half piston 3 is fixedly mounted in the one end in portion and cushion collar 4, one end of the cylinder body 1 are provided with lower cover 7, and the lower cover 7 is located at cylinder body One end inside 1 is machined with annular groove, and the annular groove mounted inside has restricting orifice 6, and the restricting orifice 6 passes through gland 5 It is encapsulated in inside annular groove, the outer face of the lower cover 7 is provided with sealing gland 8 and scraping dirt circle 9, the sealing gland 8 and scrapes Dirt circle 9 is engaged with the outer wall of piston rod 10.
Further, the groove width of the internal annular groove of lower cover 7 is more than the thickness of restricting orifice 6, can ensure throttle orifice Plate 6 is put into after annular groove, can be along piston rod slidably.
Further, the edge of the restricting orifice 6 is along the circumferential direction uniformly machined with multiple through holes 601;The throttling Orifice plate 6 is machined with annular protrusion 602 with the end face that gland 5 is engaged, and can ensure that through hole 601 is not glanded 5 end face and sealed Stifled, the end face that the restricting orifice 6 is engaged with the annular groove step surface of lower cover 7 is plane, and lower cover 7 can be ensured to throttle orifice The through hole 601 of plate 6 is blocked.Changed by the cooperation between restricting orifice 6 and gland 5 and lower cover 7, obtained throttling buffering Effect.
Further, the centre bore of the cushion collar 4 and restricting orifice 6 is using gap cooperation, can ensure fluid from Close gap circulation.In buffer stage, effectively throttled by the cooperation between cushion collar 4 and restricting orifice 6, and then play Good cushioning effect.
Further, the length of the cushion collar 4 has a variety of different specifications, to adapt to wanting for different cushion strokes Ask.
Using the operating method of any one oil cylinder of hydraulic headstock gear buffer unit:
Embodiment 2:
Such as Fig. 1, before buffering starts, cushion collar 4 follows the quick motion together of piston rod 10, and now cushion collar 4 is located at cylinder Any damping buffering effect is not played inside body 1, hydraulic oil promotes piston rod 10 quickly to move so that stop gate can be rapid Fall, quick closedown current;So as to ensure that the purpose of quick closedown.
Embodiment 3:
Such as Fig. 2, in buffer stage, when stop gate reaches end of travel, when will reach gate sill, cushion collar 4 is right End is firstly inserted into restricting orifice 6, and the cross-sectional flow area moment of hydraulic oil reduces, the hydraulic fluid pressure liter in the left side of restricting orifice 6 Height, promote restricting orifice 6 to move right, restricting orifice 6 is compressed tightly against on the step of lower cover 7 so that ring on restricting orifice 6 16 uniform through holes of shape are closed, and hydraulic oil can only be formed by the external diameter of cushion collar 4 and the internal diameter of restricting orifice 6 Annulus flow to fuel tank, serve annulus throttling effect, make the speed of rapid door reduce rapidly, finally gently Fall on gate sill, thoroughly close current, avoid the percussion to bottom bank;And then serve good cushioning effect.
Embodiment 4:
Such as Fig. 3, in quick open stage, when emergency is released, it is necessary to when opening gate, oil cylinder piston to left movement, Now high-voltage oil liquid is flowed into from hydraulic fluid port, is partly into the right chamber of cushion collar 4, and a part is entered by restricting orifice 6 In the chamber in the left side of cushion collar 4, Qi Menshi, the hydraulic fluid pressure on the right side of restricting orifice 6 is higher than the pressure in the left side of restricting orifice 6, Hydraulic oil promotes restricting orifice 6 to left movement so that the annular protrusion 602 in the left side of restricting orifice 6 is close on gland 5, makes pressure A very big gap is formd between lid 5 and restricting orifice 6, the hydraulic oil that hydraulic fluid port enters can be uniform by restricting orifice 6 16 through holes 601 enter the left side of restricting orifice 6, high-voltage oil liquid is swimmingly flowed through, almost without the pressure loss, lock can be made Door is quickly opened and avoids the rise for opening a pressure, avoids having an impact the life-span of potted component.
By above-mentioned description, those skilled in the art completely can be in the model without departing from this invention technological thought In enclosing, various changes and amendments are carried out all within protection scope of the present invention.The unaccomplished matter of the present invention, belongs to ability The common knowledge of field technique personnel.

Claims (4)

1. a kind of oil cylinder of hydraulic headstock gear buffer unit, it includes cylinder body(1), the cylinder body(1)Sliding fit inside is provided with Load-bearing piston(2), the load-bearing piston(2)Inside be installed with piston rod(10), it is characterised in that:The piston rod (10)Positioned at cylinder body(1)Half piston is fixedly mounted in internal one end(3)And cushion collar(4), the cylinder body(1)One end be provided with Lower cover(7), the lower cover(7)Positioned at cylinder body(1)Internal one end is machined with annular groove, and the annular groove mounted inside has throttling Orifice plate(6), the restricting orifice(6)Pass through gland(5)It is encapsulated in inside annular groove, the lower cover(7)Outer face be provided with Sealing gland(8)With scraping dirt circle(9), the sealing gland(8)With scraping dirt circle(9)With piston rod(10)Outer wall be engaged;
The lower cover(7)The groove width of internal annular groove is more than restricting orifice(6)Thickness, restricting orifice can be ensured(6)It is put into , can be along piston rod slidably after annular groove;
The restricting orifice(6)Edge be along the circumferential direction uniformly machined with multiple through holes(601);The restricting orifice(6)With Gland(5)The end face being engaged is machined with annular protrusion(602), through hole can be ensured(601)It is not glanded(5)End face sealed It is stifled, the restricting orifice(6)With lower cover(7)The end face that is engaged of annular groove step surface be plane, lower cover can be ensured(7)It is right Restricting orifice(6)Through hole(601)Blocked.
A kind of 2. oil cylinder of hydraulic headstock gear buffer unit according to claim 1, it is characterised in that:The cushion collar(4) With restricting orifice(6)Centre bore using gap coordinate, can ensure fluid from fit clearance circulate.
A kind of 3. oil cylinder of hydraulic headstock gear buffer unit according to claim 1, it is characterised in that:The cushion collar(4) Length there are a variety of different specifications, to adapt to the requirement of different cushion strokes.
4. using the operating method of claim 1-3 any one oil cylinder of hydraulic headstock gear buffer units, it is characterised in that slow Before washing the beginning open, cushion collar(4)Follow piston rod(10)Quickly move together, now cushion collar(4)Positioned at cylinder body(1)Do not rise inside Acted on to any damping buffering, hydraulic oil promotes piston rod(10)It is quick mobile so that stop gate can fall rapidly, quickly Close current;
In buffer stage, when stop gate reaches end of travel, when will reach gate sill, cushion collar(4)Right-hand member is inserted first Enter restricting orifice(6)In, the cross-sectional flow area moment of hydraulic oil reduces, restricting orifice(6)The hydraulic fluid pressure rise in left side, is pushed away Dynamic restricting orifice(6)Move right, by restricting orifice(6)It is compressed tightly against lower cover(7)Step on so that restricting orifice(6) 16 uniform through holes of upper annular are closed, and hydraulic oil can only pass through cushion collar(4)External diameter and restricting orifice(6)'s The annulus that internal diameter is formed flows to fuel tank, serves the effect of annulus throttling, makes the speed of stop gate reduce rapidly, Finally gently fall on gate sill, thoroughly close current, avoid the percussion to bottom bank;
In quick open stage, when emergency is released, it is necessary to when opening stop gate, oil cylinder piston is now high to left movement Press oil liquid to flow into from hydraulic fluid port, be partly into cushion collar(4)Right chamber in, a part passes through restricting orifice(6)Into slow Punching set(4)In the chamber in left side, Qi Menshi, restricting orifice(6)The hydraulic fluid pressure on right side is higher than restricting orifice(6)The pressure in left side Power, hydraulic oil promote restricting orifice(6)To left movement so that restricting orifice(6)The annular protrusion in left side(602)It is close to gland (5)On, make gland(5)With restricting orifice(6)Between form a very big gap, the hydraulic oil that hydraulic fluid port enters can pass through Restricting orifice(6)16 uniform through holes(601)Into restricting orifice(6)Left side, high-voltage oil liquid is swimmingly flowed through, almost do not have There is the pressure loss, stop gate can be made quickly to open and avoid the rise of opening a pressure, avoid the life-span to potted component Have an impact.
CN201611104738.8A 2016-12-05 2016-12-05 A kind of oil cylinder of hydraulic headstock gear buffer unit and operating method Active CN106678125B (en)

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110159610B (en) * 2019-04-26 2020-11-06 平高集团有限公司 Plug of hydraulic device working cylinder and hydraulic device working cylinder
CN110242639B (en) * 2019-04-26 2020-11-06 平高集团有限公司 Hydraulic device working cylinder and plug thereof
CN110159615B (en) * 2019-04-26 2021-03-09 平高集团有限公司 Buffer sleeve and working cylinder of hydraulic device using same
CN110242640B (en) * 2019-04-26 2020-11-06 平高集团有限公司 Buffer sleeve, working cylinder of hydraulic device and hydraulic operating mechanism

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Publication number Priority date Publication date Assignee Title
SE347046B (en) * 1969-11-07 1972-07-24 Monsun Tison Ab
JPS51123486A (en) * 1975-04-18 1976-10-28 Howa Seimitsu Kogyo Kk Air cylinder
DE4401871A1 (en) * 1994-01-22 1995-07-27 Claas Ohg End position damper for pressure medium cylinder
CN201330768Y (en) * 2008-12-05 2009-10-21 韶关液压件厂有限公司 Floating type cushioning device for hydraulic cylinder
CN103851022A (en) * 2012-11-30 2014-06-11 无锡市协新气动有限公司 Hydraulic buffer
CN203146480U (en) * 2013-01-31 2013-08-21 无锡西姆莱斯石油专用管制造有限公司 Rod-less cavity side buffer structure for hydraulic cylinder
CN206257107U (en) * 2016-12-05 2017-06-16 中船重工中南装备有限责任公司 A kind of oil cylinder of hydraulic headstock gear buffer unit

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