CN102444669B - Gas floating cushion for gas floating bearing - Google Patents
Gas floating cushion for gas floating bearing Download PDFInfo
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- CN102444669B CN102444669B CN201010508109.8A CN201010508109A CN102444669B CN 102444669 B CN102444669 B CN 102444669B CN 201010508109 A CN201010508109 A CN 201010508109A CN 102444669 B CN102444669 B CN 102444669B
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- air
- bearing
- pressure chamber
- undersetting
- floating cushion
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Abstract
The invention discloses a gas floating cushion for a gas floating bearing, which is used for connecting a sliding block with a guide rail, and comprises an upper supporting seat, a lower supporting seat and a connecting component. One end of the connecting component is movably connected with the upper supporting seat; the connecting component can move in a certain range with respect to the upper supporting seat; the other end of the connecting component is connected with one end of the lower supporting seat; the end surface of the other end of the lower supporting seat is a gas floating surface; and the lower supporting seat is driven to move by the movement of the connecting component with respect to the upper supporting seat, thereby changing an air gap between the gas floating surface and the guide rail. The gas floating cushion for the gas floating bearing, which is provided by the invention, can be used for regulating the thickness of a gas film when the gas floating bearing works, so that the gas floating rigidity reaches an optimal value.
Description
Technical field
The present invention relates to floating cushion, relate in particular to a kind of floating cushion for air-bearing.
Background technique
Air-bearing is the critical component of ultra precise measurement and processing system, it have clean, without the advantage such as friction.Along with the development of the air-bearing applications such as nanometer technology, advanced optical device and intergrated circuit, the static properties of air-bearing and positioning precision are had higher requirement.
Stiffness characteristics is one of important indicator of weighing air-bearing, a key factor that affects stiffness characteristics is air-film thickness, from the rigidity of air-bearing and the relation curve of air-film thickness, can find out, the rigidity that increases air-bearing with air-film thickness is one first increases the curve reducing afterwards, therefore, exist optimum gas film thickness value to make the rigidity of air-bearing reach maximum.
Tradition air-bearing is comprised of guide rail (guider) and slide block (slider), guide material is granite or alloy material, sliding block material is stainless steel, aluminum alloy or pottery, on slide block, have air flue and throttle orifice, gas in source of the gas by the road, air flue and throttle orifice inject in guide rail and space of slider, realize and lubricating, make can carry out relative movement between slide block and guide rail, slider surface forms air bearing surface to the face of guide rail.The shortcoming of tradition air-bearing be on slide block directly processing air bearing surface, offer throttle orifice, difficulty of processing is large, cost is high, and the air-film thickness of traditional air-bearing is non-adjustable, if the processing of air-bearing and assembling do not make the air-film thickness of air-bearing reach optimum value, this air-bearing in use its rigidity cannot reach maximum.
Air bearing surface requirement on machining accuracy is higher, and it need reach higher planeness (0.5 μ m~2 μ m) and roughness (0.2 μ m~0.4 μ m) processing request in larger areal extent.In recent years, for reducing processing and assembling difficulty, reduce processing cost, the form that air-bearing adopts guide rail, slide block and floating cushion (air-pad) to coordinate more, floating cushion material adopts stainless steel, aluminum alloy or pottery more, on floating cushion, process air bearing surface, throttle orifice and air flue, floating cushion is loaded on slide block, realizes the relative movement between slide block and guide rail.Between floating cushion and slide block, adopt screw (double-screw bolt or bolt) to be connected or button-head hinge connects.For the structure being connected by screw (double-screw bolt or bolt) between floating cushion and slide block, air-film thickness value depends on assembly precision completely, has increased processing and assembling difficulty, and is difficult to make air-film thickness to reach optimum range; For the structure being connected by button-head hinge between floating cushion and slide block, during floating cushion ventilation, (in air-bearing working procedure) air-film thickness is non-adjustable, only after floating cushion is died, by the connecting thread between adjusting soccer star's hinge rear end and slide block, complete the adjusting of air-film thickness, can not realize synchronizeing of air-bearing work and air-film thickness governing loop, be difficult to make air-film thickness to reach optimum value.
A patent of invention of the prior art " linear drive of air bearing structure and use air bearing structure " (application number: 200510085338.2) proposed the linear drive of a kind of air bearing structure and use air bearing structure, more than the length of the bearing surface of the Length Ratio fixing part side of the bearing surface of the movable part side of traveling priority grows shift motion length or grows shift motion length.In this patent of invention, on slide block, directly process air bearing surface, offer throttle orifice, difficulty of processing is large, and air-film thickness is non-adjustable.
Another patent of invention of the prior art " air supporting XY two coordinate plane sports platforms " (application number: 200410017014.0) proposed a kind of air supporting XY two coordinate moving platforms, by air-float guide rail, the XY moving platform stacking is connected, XY direction is driven respectively by two linear electric motor, the motor stator of system is all fixed on support, significantly minimizing system obtains movement inertia, the parts of relative movement are connected with air-float guide rail, and system is without friction.But with bolts between floating cushion and moving platform (slide block) in this invention, and inner without flexibly connecting, cannot carry out the adjusting of air-film thickness.
Summary of the invention
The object of the present invention is to provide a kind of floating cushion for air-bearing, can when air-bearing is worked, regulate air-film thickness, make air supporting rigidity reach optimum value.
To achieve the above object, the invention provides a kind of floating cushion for air-bearing, for connection sliding block and guide rail, comprise upper bracket, undersetting and connected element; One end of described connected element is flexibly connected with one end of described upper bracket, and this connected element moves relative to described upper bracket, and the other end of described upper bracket is connected with described slide block; The other end of described connected element is connected with one end of described undersetting, and the end face of the other end of described undersetting is air bearing surface, and described air bearing surface is towards described guide rail; Described connected element drives described undersetting to move relative to moving of described upper bracket, thereby changes the spacing between described air bearing surface and described guide rail.
The above-mentioned floating cushion for air-bearing, wherein, described upper bracket is provided with pressure chamber and pressure chamber supply air line; Described pressure chamber supply air line is communicated with described pressure chamber; The madial wall of described pressure chamber is provided with upper limit plane and lower limit plane, between described lower limit plane and upper limit plane, keeps at a certain distance away.
The above-mentioned floating cushion for air-bearing, wherein, one end of described pressure chamber is step-like, forms the upper limit plane of this pressure chamber at described step place.
The above-mentioned floating cushion for air-bearing, wherein, the madial wall of described pressure chamber is provided with locating stud, and described locating stud forms the lower limit plane of this pressure chamber.
The above-mentioned floating cushion for air-bearing, wherein, the spacing between described lower limit plane and upper limit plane is 20 μ m~50 μ m.
The above-mentioned floating cushion for air-bearing, wherein, described upper bracket is provided with pressure chamber and pressure chamber supply air line; Described pressure chamber supply air line is communicated with described pressure chamber; The madial wall of described pressure chamber is provided with upper limit plane and lower limit plane; Described connected element comprises connector element and piston, and described piston is arranged between the upper limit plane and lower limit plane of described pressure chamber, and one end of described connector element is connected with described piston, and the other end of this connector element is connected with described undersetting.
The above-mentioned floating cushion for air-bearing, wherein, described connector element is button-head hinge, and the bulb of described button-head hinge is connected with described piston, and the ball cup of described button-head hinge is connected with described undersetting.
The above-mentioned floating cushion for air-bearing, wherein, the outer race of described piston has a seal ring.
The above-mentioned floating cushion for air-bearing, wherein, described undersetting is provided with a plurality of throttle orifices and throttle orifice supply air line; Described throttle orifice supply air line is all communicated with described a plurality of throttle orifices; The relief opening of described throttle orifice is arranged in described air bearing surface.
The above-mentioned floating cushion for air-bearing, wherein, the diameter of described throttle orifice is 0.1mm~0.25mm.
The above-mentioned floating cushion for air-bearing, wherein, is provided with gap between described upper bracket and described undersetting.
The above-mentioned floating cushion for air-bearing, wherein, the spacing between described air bearing surface and described guide rail is 5 μ m~20 μ m.
The above-mentioned floating cushion for air-bearing, wherein, scribbles hard anodizing coating in described air bearing surface.
Floating cushion for air-bearing of the present invention comprises upper bracket, connected element and undersetting, upper bracket is for being connected with slide block, connected element connects upper bracket and undersetting, one end face of undersetting forms air bearing surface, and connected element can move relative to upper bracket, thereby drives undersetting to move, reach the object that regulates air-film thickness, therefore, the floating cushion for air-bearing of the present invention can regulate air-film thickness when air-bearing is worked, and makes air supporting rigidity reach optimum value;
The floating cushion that the connected element of the floating cushion for air-bearing of the present invention adopts button-head hinge to be used in air-bearing has self-regulation ability, can apply uniform power to guide rail, reduce air bearing surface and the impact of throttle orifice quality of processing on air-bearing usability;
In the air bearing surface of the floating cushion for air-bearing of the present invention, scribble hard anodizing coating, increased hardness and the wear-resisting property of air bearing surface.
Accompanying drawing explanation
Floating cushion for air-bearing of the present invention is provided by following embodiment and accompanying drawing.
Fig. 1 is that the present invention is for the stereogram of the floating cushion of air-bearing.
Fig. 2 is that the present invention is for the sectional view of the floating cushion of air-bearing.
Fig. 3 is that the present invention is applied to the schematic diagram of air-bearing for the floating cushion of air-bearing.
Embodiment
Below with reference to Fig. 1~Fig. 3, the floating cushion for air-bearing of the present invention is described in further detail.
Floating cushion for air-bearing of the present invention comprises upper bracket, undersetting and connected element;
One end of described connected element is flexibly connected with described upper bracket, and this connected element can move within the specific limits relative to described upper bracket;
The other end of described connected element is connected with one end of described undersetting, and the end face of the other end of described undersetting is air bearing surface;
Described connected element drives described undersetting to move relative to moving of described upper bracket, thereby changes the spacing between described air bearing surface and guide rail.
Now with a preferred embodiment, describe the floating cushion for air-bearing of the present invention in detail:
Referring to Fig. 1, the floating cushion for air-bearing of the present embodiment comprises upper bracket 100, undersetting 200 and connected element (not shown);
One end of described upper bracket 100 is for being connected with slide block, and the end face of this end forms attachment face 110;
The end face of described undersetting 200 one end forms air bearing surface 210.
Referring to Fig. 2, described upper bracket 100 is provided with pressure chamber 120 and pressure chamber supply air line 130;
Described pressure chamber supply air line 130 is communicated with described pressure chamber 120, and described pressure chamber supply air line 130 communicates with external air source, and the gas of external air source injects described pressure chamber 120 by described pressure chamber supply air line 130;
In the present embodiment, one end of described pressure chamber 120 is step-like, and this pressure chamber 120 forms upper limit plane 121 at step place;
The madial wall of described pressure chamber 120 is provided with locating stud 122, and the outer side wall of this locating stud 122 forms lower limit plane 123;
Spacing between described lower limit plane 123 and described upper limit plane 121 is 20 μ m~50 μ m.
Continuation is referring to Fig. 2, and in the present embodiment, described connected element comprises linkage members and piston 320, and this linkage members adopts button-head hinge 310 to realize;
Described piston 320 is step-like, the external diameter of these piston 320 one end is greater than the external diameter of these piston 320 the other ends, the large one end of described piston 320 external diameters is arranged between the lower limit plane 123 and upper limit plane 121 of described pressure chamber 120, and the large one end of described piston 320 external diameters can be moved between the lower limit plane 123 of described pressure chamber 120 and upper limit plane 121;
The bulb 311 of described button-head hinge 310 is arranged on the little one end of described piston 320 external diameters;
The outer race of one end that described piston 320 external diameters are large has a seal ring 330.
Continuation is referring to Fig. 2, and one end of described undersetting 200 is provided with cavity 240, and for connecting described button-head hinge 310, this cavity 240 matches with the ball cup 312 of described button-head hinge 310, and the ball cup 312 of described button-head hinge 310 is arranged in this cavity 240;
Adopt the advantage of button-head hinge to be that the floating cushion that is used in air-bearing has self-regulation ability, can apply uniform power to guide rail, reduce air bearing surface and the impact of throttle orifice quality of processing on air-bearing usability;
Described undersetting 200 is also provided with a plurality of throttle orifices 220 and throttle orifice supply air line 230;
Described throttle orifice supply air line 230 is all communicated with described a plurality of throttle orifices 220, and this throttle orifice supply air line 230 communicates with external air source, and the gas of external air source injects described a plurality of throttle orifices 220 by described throttle orifice supply air line 230;
The relief opening of described throttle orifice 220 is arranged in described air bearing surface 210;
The diameter of described throttle orifice 220 is 0.1mm~0.25mm.
Between described upper bracket 100 and described undersetting 200, be provided with a gap 400, spacing for described button-head hinge 310 on three rotary freedom Rx, Ry, Rz;
Described upper bracket 100 adopts aviation aluminium with described undersetting 200, the processing method of described throttle orifice 220 is on aluminium material, to implement boring or laser boring, for guaranteeing hardness and the wear resistance of described air bearing surface 210, in described air bearing surface 210, coat hard anodizing coating.
In conjunction with Fig. 2 and Fig. 3, the working principle of the floating cushion for air-bearing of the present embodiment is described: the upper bracket 100 of floating cushion is threaded onto slide block 600 by described attachment face 110, external air source is injected described throttle orifice 220 by the air with certain pressure by described throttle orifice supply air line 230, air enters the gap between described air bearing surface 210 and guide rail 500 through the relief opening of described throttle orifice 220, between described air bearing surface 210 and described guide rail 500, form air film, static pressure by air film can make floating cushion side direction suspend, realize between described slide block 600 and described guide rail 500 without frictional movement, now, described piston 320 is pulled to described upper limit plane 121 places, external air source is injected described pressure chamber 120 by the air with certain pressure by described pressure chamber supply air line 130, when the pressure in described pressure chamber 120 increases gradually, described piston 320 moves to described lower limit plane 123, the mobile of described piston 320 drives described undersetting 200 to move, change the spacing between described air bearing surface 210 and described guide rail 500, change air-film thickness, regulate the adjustable described air bearing surface 210 of gas pressure of described pressure chamber supply air line 130 and described throttle orifice supply air line 230 and the spacing between described guide rail 500, reach the object that regulates air-film thickness, therefore, the floating cushion of the present embodiment can regulate air-film thickness when air-bearing is worked, make air-film thickness reach optimum value, in the present embodiment, the scope of air-film thickness is 5 μ m~20 μ m, Fig. 3 only provides the pneumatically supported layout example of side direction, and reality does not provide for supporting slider 600 and required vertical air supporting Fig. 3 of parts of being connected on it in using.
Claims (13)
1. for a floating cushion for air-bearing, for connecting slide block and the guide rail of air-bearing, it is characterized in that, comprise upper bracket, undersetting and connected element; Described upper bracket is provided with pressure chamber and pressure chamber supply air line, and extraneous gas injects described pressure chamber by described pressure chamber supply air line; Described undersetting is provided with a plurality of throttle orifices and throttle orifice supply air line, and extraneous gas injects described a plurality of throttle orifices by described throttle orifice supply air line;
One end of described connected element is flexibly connected with one end of described upper bracket, and this connected element moves relative to described upper bracket, and the other end of described upper bracket is connected with described slide block;
The other end of described connected element is connected with one end of described undersetting, and the end face of the other end of described undersetting is air bearing surface, and described air bearing surface is towards described guide rail;
Regulate the gas pressure of described pressure chamber supply air line and described throttle orifice supply air line can make described connected element drive described undersetting to move relative to moving of described upper bracket, thereby change the air clearance between described air bearing surface and described guide rail.
2. the floating cushion for air-bearing as claimed in claim 1, is characterized in that, described upper bracket is provided with pressure chamber and pressure chamber supply air line; Described pressure chamber supply air line is communicated with described pressure chamber; The madial wall of described pressure chamber is provided with upper limit plane and lower limit plane.
3. the floating cushion for air-bearing as claimed in claim 2, is characterized in that, one end of described pressure chamber is step-like, forms the upper limit plane of this pressure chamber at described step place.
4. the floating cushion for air-bearing as claimed in claim 2, is characterized in that, the madial wall of described pressure chamber is provided with locating stud, and described locating stud forms the lower limit plane of this pressure chamber.
5. the floating cushion for air-bearing as described in arbitrary claim in claim 2~4, is characterized in that, the spacing between described lower limit plane and upper limit plane is 20 μ m~50 μ m.
6. the floating cushion for air-bearing as claimed in claim 1, is characterized in that, described upper bracket is provided with pressure chamber and pressure chamber supply air line; Described pressure chamber supply air line is communicated with described pressure chamber; The madial wall of described pressure chamber is provided with upper limit plane and lower limit plane; Described connected element comprises connector element and piston, and described piston is arranged between the upper limit plane and lower limit plane of described pressure chamber, and one end of described connector element is connected with described piston, and the other end of this connector element is connected with described undersetting.
7. the floating cushion for air-bearing as claimed in claim 6, is characterized in that, described connector element is button-head hinge, and the bulb of described button-head hinge is connected with described piston, and the ball cup of described button-head hinge is connected with described undersetting.
8. the floating cushion for air-bearing as claimed in claim 6, is characterized in that, the outer race of described piston has a seal ring.
9. the floating cushion for air-bearing as described in claim 1,2,3,4,6,7 or 8, is characterized in that, described undersetting is provided with a plurality of throttle orifices and throttle orifice supply air line; Described throttle orifice supply air line is all communicated with described a plurality of throttle orifices; The relief opening of described throttle orifice is arranged in described air bearing surface.
10. the floating cushion for air-bearing as claimed in claim 9, is characterized in that, the diameter of described throttle orifice is 0.1mm~0.25mm.
11. floating cushions for air-bearing as claimed in claim 1, is characterized in that, between described upper bracket and described undersetting, are provided with gap.
12. floating cushions for air-bearing as claimed in claim 1, is characterized in that, the spacing between described air bearing surface and described guide rail is 5 μ m~20 μ m.
13. floating cushions for air-bearing as claimed in claim 1, is characterized in that, scribble hard anodizing coating in described air bearing surface.
Priority Applications (1)
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CN201010508109.8A CN102444669B (en) | 2010-10-15 | 2010-10-15 | Gas floating cushion for gas floating bearing |
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CN201010508109.8A CN102444669B (en) | 2010-10-15 | 2010-10-15 | Gas floating cushion for gas floating bearing |
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CN102444669A CN102444669A (en) | 2012-05-09 |
CN102444669B true CN102444669B (en) | 2014-03-26 |
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Families Citing this family (1)
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CN110296839B (en) * | 2019-08-13 | 2024-02-06 | 中国工程物理研究院机械制造工艺研究所 | Air film pressure testing device and testing method for gas bearing |
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CN2648397Y (en) * | 2003-07-21 | 2004-10-13 | 哈尔滨量具刃具厂 | Z axle auto-protector for dual coordinate measuring implement |
CN1564317A (en) * | 2004-03-18 | 2005-01-12 | 上海交通大学 | Air floation XY coordinates plane movoment platform |
CN1727710A (en) * | 2004-07-26 | 2006-02-01 | 发那科株式会社 | Air bearing structure and linear driving device using said air bearing structure |
CN1995771A (en) * | 2006-01-04 | 2007-07-11 | 发那科株式会社 | Method of assembling air bearing, air bearing and linear drive unit equipped with the same |
CN101349870A (en) * | 2008-08-07 | 2009-01-21 | 上海微电子装备有限公司 | Two-freedom degree electric machine actuating mechanism and corresponding six-freedom degree micromotion platform |
CN101490430A (en) * | 2006-06-30 | 2009-07-22 | 瑞尼斯豪公司 | Gas bearing fabrication method |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
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JPH10263964A (en) * | 1997-03-19 | 1998-10-06 | Toyoda Mach Works Ltd | Slip guiding device |
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2010
- 2010-10-15 CN CN201010508109.8A patent/CN102444669B/en active Active
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
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CN2648397Y (en) * | 2003-07-21 | 2004-10-13 | 哈尔滨量具刃具厂 | Z axle auto-protector for dual coordinate measuring implement |
CN1564317A (en) * | 2004-03-18 | 2005-01-12 | 上海交通大学 | Air floation XY coordinates plane movoment platform |
CN1727710A (en) * | 2004-07-26 | 2006-02-01 | 发那科株式会社 | Air bearing structure and linear driving device using said air bearing structure |
CN1995771A (en) * | 2006-01-04 | 2007-07-11 | 发那科株式会社 | Method of assembling air bearing, air bearing and linear drive unit equipped with the same |
CN101490430A (en) * | 2006-06-30 | 2009-07-22 | 瑞尼斯豪公司 | Gas bearing fabrication method |
CN101349870A (en) * | 2008-08-07 | 2009-01-21 | 上海微电子装备有限公司 | Two-freedom degree electric machine actuating mechanism and corresponding six-freedom degree micromotion platform |
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