CN101303011A - Piston for pressure balance - Google Patents

Piston for pressure balance Download PDF

Info

Publication number
CN101303011A
CN101303011A CNA2008101232049A CN200810123204A CN101303011A CN 101303011 A CN101303011 A CN 101303011A CN A2008101232049 A CNA2008101232049 A CN A2008101232049A CN 200810123204 A CN200810123204 A CN 200810123204A CN 101303011 A CN101303011 A CN 101303011A
Authority
CN
China
Prior art keywords
piston
pressure
ripple
side wall
pressure balance
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CNA2008101232049A
Other languages
Chinese (zh)
Inventor
王勇
刘正士
陈恩伟
葛运建
何凯
陆益民
陈奇
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hefei University of Technology
Original Assignee
Hefei University of Technology
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hefei University of Technology filed Critical Hefei University of Technology
Priority to CNA2008101232049A priority Critical patent/CN101303011A/en
Publication of CN101303011A publication Critical patent/CN101303011A/en
Pending legal-status Critical Current

Links

Images

Landscapes

  • Diaphragms And Bellows (AREA)

Abstract

The invention discloses a piston for pressure balance, which is characterized in that the piston is a cylindrical tube piece with one end closed, the side wall of the longitudinal section of the cylindrical tube piece along the axle line is a V-shaped corrugated surface; the outer side wall and the inner side wall of the V-shaped corrugated surface have the same corrugation shape and the outer side wall is at the same level with the inner side wall along the radial direction. By utilizing the pressure balance, the piston of the invention can have the reliable sealing performance under the pressure in the deep sea and maintain the flexible movement of the piston.

Description

Piston for pressure balance
Technical field
The present invention relates to air locking, more particularly especially be applied under water packed-piston member in the pressure balancing structure.
Background technique
Along with going deep into of oceanographic observation and exploitation, instrument and equipment under water, comprise that underwater robot, underwater sensor, underwater operation tool, underwater engine source etc. constantly move towards the ocean, when facing the big flood stress problems of 3800 meters oceans of mean depth, only adopt withstand voltage design, not only can cause volume, the weight of instrument and equipment under water to increase, and can cause under water that the precision of force transducer reduces even can't work.Pressure balance is that Pressure Compensation Technology is the effective way that addresses this problem at present.
So far, domestic and international applied pressure balance mainly is to utilize elastic element, as compensating film is that diaphragm, soft capsule are that resiliently deformable takes place under the effect of water pressure for leather bag, bellows etc., makes the oil pressure of the oil-filled inside of instrument and equipment under water and outside hydraulic pressure tend to balance.But along with the long-pending increasing that changes of interior oil liquid of instrument and equipment under water, the pressure balance elastomer is that the distortion of diaphragm, soft capsule or bellows strengthens, and the inside and outside differential pressure of instrument and equipment also strengthens under water, and the pressure balanced ability of elastomer constantly changes and reduces.Soft capsule and membrane device are very easily impaired simultaneously.
The piston-type pressure Equilibrator utilizes piston moving in cylinder body under hydraulic action, makes the oil pressure of the oil-filled inside of instrument and equipment under water and outside hydraulic pressure tend to balance.This method is not to utilize the distortion of elastic element, and piston that is utilized and cylinder body can be without rubber materials; When hydraulic pressure increase piston displacement increased thereupon, it is less that inside and outside differential pressure still can keep; On principle, can be competent at the long-term work of instrument and equipment under abyssal environment under water.But piston moving under the deep-sea should guarantee strict sealing, moves again flexibly, and this is new problem and new challenge that existing piston seal technology is faced.Usually the structural type of piston packing, when the pistons work fluid pressure increases, the contact pressure increase between itself and cylinder body; contact width increases and is comparatively obvious; the resistance that causes piston to move increases, and the inside and outside differential pressure of instrument and equipment increases under water, and the pressure balance ability reduces.
Patent 03113254.5 has proposed a kind of underwater robot multi-axis force transducer pressure equaliser, disclosing a kind of collection sealing and dustproof construction is unitary whole formula thin-walled tubular piston, but according to the concrete shape that is proposed in its embodiment, can cause the axial rigidity of piston bigger in actual applications, thereby be difficult to reach preferably the requirement of the less axial rigidity of elastic piston of patent 03113254.5; Simultaneously, it is less to cause the radius of curvature at the ripple top that piston contacts with casing wall to be difficult to, and makes that under identical interference fit, the contact width between piston and casing wall is bigger, and the surface friction drag that piston moves is bigger.In addition, patent is that disclosed piston form is too meticulous on its dustproof construction in 03113254.5, is difficult to processing, has also increased the contact width between piston and the casing wall simultaneously.
Summary of the invention
The present invention is for avoiding existing deficiency in the above-mentioned prior art, a kind of piston for pressure balance is provided, utilizing pressure balance to make and still can obtain reliable sealing performance under deep sea pressure, and can keep the piston flexible movement.
Technical solution problem of the present invention adopts following technological scheme:
The structural feature of piston for pressure balance of the present invention is that described piston is the cylindric pipe fitting of end sealing, at described cylindric pipe fitting along on the longitudinal section of medial axis, its sidewall is " V " type ripple, the outer side wall of described " V " type ripple is identical bellows-shaped with madial wall, and outer side wall is on madial wall translation position radially.
What the structural feature of piston for pressure balance of the present invention also was described " V " type ripple is shaped as joining of the opposite parabolic segment of opening; Or " V " type ripple is sinusoidal curve or cosine curve; Or the trough of " V " type ripple and wave base be arc section, and forward position and back are along being straightway.
Compared with the prior art, beneficial effect of the present invention is embodied in:
1, the normal direction wall thickness that is between ripple top and the trough of the normal direction wall ratio of the present invention at the trough place of the ripple top of piston and casing wall contact and piston ripple diameter dimension minimum is big, compare with the bellows that waits wall thickness, the axial rigidity of piston of the present invention further reduces.
2, the ripple of piston of the present invention is " V " type, and the curvature of ripple changes with radial dimension, the curvature minimum of ripple top and trough, and under same interference fit, the contact width of the sealing contacting point between piston ripple top and the casing wall can be less.
3, piston of the present invention, when water depth pressure increased, the contact pressure of the sealing contacting point between piston ripple top and the casing wall increased, and produced the self-adapting seal ability that changes with water depth pressure.
4, piston of the present invention, when water depth pressure increased, elastic shrinkage axially took place in it, and the volume of the Seal cage that forms between piston ripple and casing wall reduces, and the oil pressure in the chamber increases, with the hydraulic pressure and the oil pressure balance of Seal cage outside.Again because the bulk modulus of fluid is bigger, so under the deep-water pressure effect, the contact width of the sealing contacting point between piston ripple top and the piston in cylinder wall is still less, the normal force of the sealing contacting point between piston ripple top and the piston in cylinder wall is less, and the surface friction drag that piston moves is less.
Description of drawings
Fig. 1 is the structural representation of parabola combination for setting of the present invention " V " type ripple.
Fig. 2 is provided with V for the present invention " the type ripple be sine or cosine structural representation.
Fig. 3 is the structural representation of circle with the straight line combination for setting of the present invention " V " type ripple.
Fig. 4 is the present invention and cylinder body cooperating structure schematic representation.
Number in the figure: 1 piston, 11 outer side walls, 12 madial walls, 2 ripple tops, 3 cylinder bodies, 4 Seal cages, 5 are instrument and equipment outside, 6 instrument and equipment inside, 7 internal pistons, 8 piston closes ends under water under water.
Below by embodiment, the invention will be further described in conjunction with the accompanying drawings:
Embodiment
Referring to Fig. 1, the present embodiment piston is the cylindric pipe fitting of end sealing, at cylindric pipe fitting along on the longitudinal section of medial axis, its sidewall is " V " type ripple, the outer side wall 11 of " V " type ripple is identical bellows-shaped with madial wall 12, and outer side wall 11 is on madial wall 12 translation position radially.
In concrete the enforcement, the shape of " V " type ripple can for:
" V " type ripple as shown in Figure 1 is joining of the opposite parabolic segment of opening;
" V " type ripple as shown in Figure 2 is sinusoidal curve or cosine curve;
The trough and the wave base of " V " type ripple as shown in Figure 3 are arc section, and forward position and edge, back are straightway.
In concrete the enforcement, the ripple top 2 of piston 1 and the madial wall interference fit of cylinder body 3 form Seal cage 4, are full of fluid in the Seal cage 4.The madial wall of cylinder body 3 is cylindric through hole, an end and under water the outside 5 residing seawater of instrument and equipment communicate, bear seawater pressure, the other end and under water the fluid of instrument and equipment inside 6 communicate.Internal piston 7 and under water instrument and equipment inside 6 communicate, be full of fluid.Piston closes end 8 is outside 5 residing seawater of instrument and equipment and internal piston 7 separate under water.
When the residing depth of water of instrument and equipment under water increases, outside water depth pressure increases, the active force that acts on the piston closes end outside increases, disregard the frictional force between piston ripple top and casing wall, then piston moves to the inside of instrument and equipment under water, the fluid volume-diminished of instrument and equipment inside under water, the pressure of inner fluid increases with the seawater pressure of outside, makes instrument and equipment internal oil pressure and outside hydraulic balance under water.
Because internal piston 7 and under water instrument and equipment inside 6 communicate, so the fluid of internal piston 7 increases with water depth pressure, cause pressure between the madial wall of piston ripple top 2 and cylinder body 3 also along with the water depth pressure increase and increase.
Under water under the effect of the hydraulic pressure of instrument and equipment outside and internal oil pressure, because the less axial rigidity of piston, piston generation axial elasticity shrinks, make the interior oil hydraulic coupling of Seal cage 4 increase, between the oil pressure of the hydraulic pressure of Seal cage 4 and seal ring outside and internal piston, obtain pressure balance with the seawater pressure of outside; Again because the bulk modulus of liquid is bigger, so contact width is still less; Normal force between piston ripple top and the cylinder body madial wall is less, and the surface friction drag that piston moves is less; Reach reliable, the mobile requirement flexibly of piston seal.Make that the inside and outside differential pressure of instrument and equipment is less under water, guarantee the pressure balance ability of piston for pressure balance under any depth of water.
When the depth of water of instrument and equipment work under water reduces, disregard the frictional force between piston ripple top and casing wall, then piston moves to the outside of instrument and equipment under water, the pressure of the fluid of instrument and equipment inside reduces with the seawater pressure of outside and reduces under water, makes the oil pressure and the outside hydraulic balance of instrument and equipment inside under water.Along with the hydraulic pressure of outside and reducing of internal oil pressure, piston generation axial elongation, the volume of the Seal cage that forms between piston ripple and casing wall increases, the pressure of Seal cage 4 inner fluid reduces with the seawater pressure of outside and reduces, and obtains pressure balance between the oil pressure of the hydraulic pressure of Seal cage 4 and seal ring outside and internal piston; Contact pressure between same piston ripple top and casing wall reduces and reduces along with seawater pressure, but that contact width still keeps is less; Normal force between piston ripple top and casing wall is less, and the surface friction drag that piston moves is less; Piston seal is reliable, flexibly mobile.Guarantee the pressure balance ability of piston for pressure balance under any depth of water.
Piston closes end 8 can adopt thin thickness, if consider the frictional force between piston ripple top and casing wall, when end thrust suffered on the piston during less than frictional force, piston does not move, thin piston closes end 8 is just as diaphragm, elastic springing taking place, make that the volume of instrument and equipment inside changes under water, causes the pressure and the outside hydraulic balance of inner fluid.
In concrete the enforcement, on the longitudinal section at " V " type ripple place, the tangent line that any can be set on the waviness curve arbitrarily is not more than 20 with the minimum value of the acute angle angle of radial line and spends, and makes the piston ripple become small angle " V " type ripple, guarantees that piston has less axial rigidity.

Claims (2)

1, a kind of piston for pressure balance, it is characterized in that described piston is the cylindric pipe fitting of end sealing, at described cylindric pipe fitting along on the longitudinal section of medial axis, its sidewall is " V " type ripple, the outer side wall of described " V " type ripple is identical bellows-shaped with madial wall, and outer side wall is on madial wall translation position radially.
2, piston for pressure balance according to claim 1, what it is characterized in that described " V " type ripple is shaped as joining of the opposite parabolic segment of opening; Or " V " type ripple is sinusoidal curve or cosine curve; Or the trough of " V " type ripple and wave base be arc section, and forward position and back are along being straightway.
CNA2008101232049A 2008-06-11 2008-06-11 Piston for pressure balance Pending CN101303011A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CNA2008101232049A CN101303011A (en) 2008-06-11 2008-06-11 Piston for pressure balance

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CNA2008101232049A CN101303011A (en) 2008-06-11 2008-06-11 Piston for pressure balance

Publications (1)

Publication Number Publication Date
CN101303011A true CN101303011A (en) 2008-11-12

Family

ID=40113056

Family Applications (1)

Application Number Title Priority Date Filing Date
CNA2008101232049A Pending CN101303011A (en) 2008-06-11 2008-06-11 Piston for pressure balance

Country Status (1)

Country Link
CN (1) CN101303011A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106996369A (en) * 2017-05-23 2017-08-01 中国矿业大学(北京) Based on bionical multilevel hierarchy reciprocating type plunger
CN109611327A (en) * 2019-02-14 2019-04-12 吉林大学 The asymmetric husky wear-resisting oil pump plunger piston of groove-shaped storage
CN111287694A (en) * 2020-02-05 2020-06-16 史先德 Liquid balance type device
CN116085250A (en) * 2023-01-10 2023-05-09 山东大学 Integrated flow distribution type low-leakage plunger pair device

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106996369A (en) * 2017-05-23 2017-08-01 中国矿业大学(北京) Based on bionical multilevel hierarchy reciprocating type plunger
CN106996369B (en) * 2017-05-23 2020-04-14 中国矿业大学(北京) Multi-stage structure reciprocating plunger based on bionics
CN109611327A (en) * 2019-02-14 2019-04-12 吉林大学 The asymmetric husky wear-resisting oil pump plunger piston of groove-shaped storage
CN111287694A (en) * 2020-02-05 2020-06-16 史先德 Liquid balance type device
CN116085250A (en) * 2023-01-10 2023-05-09 山东大学 Integrated flow distribution type low-leakage plunger pair device
CN116085250B (en) * 2023-01-10 2023-11-24 山东大学 Integrated flow distribution type low-leakage plunger pair device

Similar Documents

Publication Publication Date Title
US7686308B2 (en) Fluid-activated shaft seal
CN101303011A (en) Piston for pressure balance
CN103486096B (en) Avoid the piston-type deep sea pressure compensator of seawater pollution
CN103921283B (en) One is water hydraulic manipulator joint drive unit under water
CN207830270U (en) Hydrostatic support type servo hydraulic cylinder
JP2012092976A (en) Rotating shaft seal
JP2010190300A (en) Rotary shaft seal
EP2954294B1 (en) Displacement level sensor and seal and pivot assembly for displacement level sensor
CN101303081A (en) Piston seal ring
US20150144216A1 (en) Piston accumulator
JP2008546951A (en) Reciprocating pump
CN1746644A (en) Pressure sensor in deep-sea and use thereof
CN201714976U (en) Mechanical oil seal
CN106030168A (en) Dynamic seal
CN214221184U (en) Novel hob pressure compensation structure
CN201844024U (en) Rubber coated V-shaped spring mechanical sealing device
CN214502750U (en) Supporting device for balance spring in differential pressure transmitter and differential pressure transmitter
CN112994342A (en) Underwater large-depth direct-connected electric cylinder
CN217327903U (en) Fluid driving device
JP4836743B2 (en) Seal structure of sliding part
CN110542442A (en) Magnetic rotary encoder for deep sea
CN213117208U (en) Novel AMT gearbox clutch actuator
CN217234392U (en) Double-lip low-friction frameless rubber oil seal
CN214824014U (en) Rigid outer oil bag structure and piston type buoyancy adjusting device
CN2627292Y (en) Corrugated tube valve

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
C12 Rejection of a patent application after its publication
RJ01 Rejection of invention patent application after publication

Open date: 20081112