CN102814529A - Automatic drilling compressing device - Google Patents

Automatic drilling compressing device Download PDF

Info

Publication number
CN102814529A
CN102814529A CN2012103056885A CN201210305688A CN102814529A CN 102814529 A CN102814529 A CN 102814529A CN 2012103056885 A CN2012103056885 A CN 2012103056885A CN 201210305688 A CN201210305688 A CN 201210305688A CN 102814529 A CN102814529 A CN 102814529A
Authority
CN
China
Prior art keywords
automatic drilling
hole
sleeve pipe
compressing
head
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
CN2012103056885A
Other languages
Chinese (zh)
Inventor
余剑峰
张�杰
辛博
肖鸿
徐佳加
唐文斌
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.)
Northwestern Polytechnical University
Original Assignee
Northwestern Polytechnical University
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 Northwestern Polytechnical University filed Critical Northwestern Polytechnical University
Priority to CN2012103056885A priority Critical patent/CN102814529A/en
Publication of CN102814529A publication Critical patent/CN102814529A/en
Pending legal-status Critical Current

Links

Images

Landscapes

  • Processing Of Stones Or Stones Resemblance Materials (AREA)

Abstract

The invention discloses an automatic drilling compressing device. Two fixing sleeves are symmetrically mounted, one end of each sleeve is positioned in a mounting hole of the corresponding fixing sleeve, limit switches are fixed to middles of the sleeves via mounting rings, pressure springs are fixed onto end surfaces of the other ends of the sleeves, each mandrel penetrates through the corresponding sleeve and the corresponding pressure spring, and the other end of each pressure spring is fixed to a limit nut via a stopper on the corresponding mandrel; and the mandrels are fixedly connected with a pressure head by fixing nuts. The springs are adopted, and the maximum compression of each spring is controlled by the corresponding limit switch; the automatic drilling compressing device is particularly applicable to compressing small skin components and wallboard components of airplanes, compressing force and compressing stroke are easy to control, close fitting among laminated materials can be guaranteed, the automatic drilling compressing device is safe and reliable in compression, influence on appearance precision of a product due to excessive compressing force is prevented owing to the limit switch, and a rubber protective pad arranged on the pressure head has a buffering effect; and the compressing device is simple and reliable in structure, small in size and low in cost, is integrally worked with automatic drilling equipment easily, and is light.

Description

A kind of hold down gag of automatic drilling
Technical field
The invention belongs to Machine Design and manufacturing technology field, relate to a kind of hold down gag, specifically, relate to a kind of hold down gag that is used for the automatic drilling of aircraft small size covering, wallboard base part parts.
Background technology
In aviation manufacturing field, hole fabrication techniques directly influences the quality of connection and the reliability of product as an important process of aircraft Assembling Production automatically.Automatically the main application of hole fabrication techniques is a laminated material, so-called laminated material, i.e. and piling up of multilayer material usually need be stacked like covering, long purlin, intercostal and to rivet behind the system through hole of back.Because in the boring procedure, the different layers storeroom produces coarse burr, promptly mixed and disorderly spiral chip; Therefore before actuator is holed endways; Need hold down gag to contact and apply certain thrust, eliminate the gap of laminated material layer and interlayer, prevent that burr from getting into processed parts.
Disclosed in patent CN101417348A " boring end effector "; Reach several kinds of end effector hold down gags that propose in " device and method of interlayer burr in the time of reducing aircraft assembling drilling " with " a kind of self adaptation micromatic setting of automatic drill riveting end effector pressure foot " in patent CN102303261A and 102513580A, described; Working stability is reliable in practical application; Have independently feeding controlling organization; Be applicable to compressing of large aircraft covering, wallboard base part; But then have following deficiency to aircraft small size covering, wallboard base part: 1) complex structure, volume and weight are all bigger, are not easy to be mounted on the small-sized end effector; 2) because some small size covering, wallboard base part curvature are bigger; Like droope snoot, radome fairing etc.; The pressure acting surface is less when causing compressing, and local pressure is bigger, and method vows that deviation is prone to cause the parts local deformation in addition; The resilience of discharge degree back part causes stacking material axially bored line decentraction, influences the drilling quality.
Summary of the invention
Deficiency for avoiding prior art to exist overcomes its complex structure, and volume weight is bigger, and is less for the parts pressure acting surface that curvature is bigger, influences the drilling quality.The present invention proposes a kind of hold down gag that is applicable to the automatic drilling of aircraft small size covering, wallboard base part.
The technical solution adopted for the present invention to solve the technical problems is: comprise fixed cover, sleeve pipe, axle, compression spring, stop nut, head, limit switch, installing ring,
The fixed cover symmetry is installed on the unit head outer wall of cylinder block; One end of two sleeve pipes lays respectively in the fixed cover installing hole, is connected with the fixed cover installing hole, and limit switch is positioned at the sleeve pipe middle part to be fixed through installing ring; Compression spring is fixed on the other end end face of sleeve pipe, and axle is passed sleeve pipe and compression spring, and the compression spring other end is fixed through the catch and the stop nut that are enclosed within on the axle; Axle is connected through hold-down nut and head.
Said fixed cover is a semi-round ring shape, and respectively there is a lug with holes at two ends, and there is outstanding square cylinder middle part, the semicircular ring outside, and cylinder is provided with installing hole, near leaded hole on the hole wall of installing hole bottom.
Said sleeve pipe is the hollow circular-tube structure, and end is circular hole, and the diameter of circular hole is less than casing inner diameter, is provided with pressure compensation opening near the casing wall of end.
Said head is conical boss, and there is guide hole at the boss center, and there is screw linkage section end, boss both sides, is provided with ribs between linkage section and boss, and glued joint rubber sheet gasket and head lower surface.
Beneficial effect
The hold down gag of the automatic drilling of the present invention adopts simple spring structure, through the maximum compressibility of limit switch control spring; To compressing of aircraft small size covering, wallboard base part, compare with the large-scale pressure foot that adopts cylinder or guide rail leading screw and pressure sensor structure, simple and reliable for structure, thrust and clamping stroke all are easy to control, can guarantee to fit tightly between laminated material.Compress safe and reliable; The setting of limit switch prevents the excessive product design precision that influences of thrust, and head is equipped with the rubber neonychium, and head can be regulated among a small circle automatically; Play cushioning effect when compressing, avoid weighing wounded, scratching what workpiece caused in the rigid pressure pin compaction process; Hold down gag has that volume is little in light weight, and cost is low, more is prone to automatic drilling equipment integratedly, is applicable to that thrust is no more than the working environment of 15kg.
Description of drawings
Below in conjunction with accompanying drawing and embodiment the hold down gag of a kind of automatic drilling of the present invention is done further explain.
Fig. 1 is the hold down gag sketch map of the automatic drilling of the present invention.
Fig. 2 is the partial sectional view of the hold down gag of the automatic drilling of the present invention.
Fig. 3 is the combination sketch map that the hold down gag of automatic drilling cooperates unit head and Connection Block.
Fig. 4 is a working state schematic representation.
Among the figure:
1. fixed cover 2. sleeve pipes 3. axles 4. compression springs 5. catch 6. stop nuts 7. hold-down nuts 8. rubber sheet gaskets 9. heads 10. guide holes 11. stop screws 12. connecting bolts 13. limit switches 14. installing rings 15. fairleads 16. installing holes 17. pressure compensation openings 18. screw holes 19. ribs 20. Connection Blocks 21. unit heads 22. workpiece 23. articulated mechanical arms.
The specific embodiment
Present embodiment is a kind of hold down gag of automatic drilling, is used for the compressing of automatic drilling of aircraft small size covering, wallboard base part.
Consult Fig. 1, Fig. 2, the hold down gag of the automatic drilling of the present invention by fixation kit, connection and guidance set, directly act on assembly and limit assembly four parts are formed; Comprise fixed cover 1, sleeve pipe 2, axle 3, compression spring 4, catch 5, stop nut 6, hold-down nut 7, rubber sheet gasket 8, head 9, guide hole 10, stop screw 11, connecting bolt 12, limit switch 13, installing ring 14, fairlead 15, installing hole 16, pressure compensation opening 17, screw hole 18, ribs 19;
The aggregate erection of hold down gag in the present embodiment, stiff end are last, and pressure effect end is installed for down from top to bottom;
Fixed cover 1 is a semi-round ring shape, and respectively there is a lug at two ends, and a bolt hole is arranged on each lug, and there is outstanding square cylinder middle part, the semicircular ring outside, and there is cylindrical installing hole 16 centre, leaded hole 15 on the hole wall near the bottom, hole; Fixed cover 1 symmetry is installed on the unit head outer wall of cylinder block; Compression spring 4 is fixed on the other end end face of sleeve pipe 2, and axle 3 is passed sleeve pipe 2 and compression spring 4, and compression spring 4 other ends are fixing with stop nut 6 through the catch 5 that is enclosed within on the axle 3; Axle 3 is connected through hold-down nut 7 and head 9.During installation, two fixed cover 1 symmetries are installed on the unit head outer wall of cylinder block, and are fixing through two groups of connecting bolts 12.
Sleeve pipe 2 is the hollow circular-tube structure, and end is circular hole, and the diameter of circular hole is less than casing inner diameter, is provided with pressure compensation opening near sleeve pipe 2 walls of end.One end of two sleeve pipes 2 lays respectively in fixed cover 1 installing hole, and is connected with fixed cover 1 installing hole, and it is fixing through installing ring 14 that limit switch 13 is positioned at sleeve pipe 2 middle parts; Two sleeve pipes 2 insert respectively in the installing hole 16 of fixed cover 1 during installation, and the degree of depth of two sleeve pipe 2 installation positions is identical, compress spacingly through stop screw 11, prevent that sleeve pipe 2 from sliding in installing hole 16 vertically.
In sleeve pipe 2, limit switch 13 is cylindrical touch switch, and the trigger point is in the switch lower end, and the upper end is connected to the input and output lead, passes fairlead 15 and links to each other with the control system.Installing ring 14 is a rubber ring, and its external diameter is than the big 2mm of internal diameter of sleeve pipe 2, is stuck in during installation on the cylindrical boss at limit switch 13 tops together to be pressed on the inwall of sleeve pipe 2 subsequently, is used to provide frictional force limit switch 13 to be fixed on the inwall of sleeve pipe 2.Its fixed position is the distance decision of trigger point, lower end of upper surface and the limit switch 13 of axle 3 by clamping stroke, is set at 10mm here.Be provided with pressure compensation opening 17 in sleeve pipe 2 outer wall lower ends near bottom surface place, diameter can keep the inside and outside air pressure balance of sleeve pipe 2 about 1.5~2mm, be convenient to axle 3 and in sleeve pipe 2, slide smoothly, also plays the effect of oil filler point simultaneously.
Axle 3 is a cylinder, and there is a step section upper end, is used for guiding slip and spacing; Thread segment is arranged at the bottom.During installation, insert the sleeve pipe 2 from the upper end of sleeve pipe 2 with gap fiting mode the lower end of axle 3, can be free to slide therein after lubricating.Compression spring 4 one ends are fixed on the lower surface of sleeve pipe 2, and the other end is fixing with stop nut 6 through the catch 5 that is enclosed within on the axle 3, and use stop nut 6 to regulate the size of compression spring pretightning force according to actual needs.
Head 9 is conical boss structure, and there is guide hole 10 at the boss center, is used to draw hole and chip removal, imports end and has chamfering, is convenient to drill bit and inserts.There is screw hole 18 linkage section end, boss both sides, is provided with ribs 19 between linkage section and boss to improve the rigidity of head.The lower end of axle 3 is connected, adjusts position and locking with nut 7 and screw hole 18 during installation.Rubber sheet gasket 8 is glued to head 9 lower surfaces, is used for the buffer protection workpiece, wearing and tearing back fast changeable.
With reference to accompanying drawing 3, be example with SFB type pneumatic type self-feed unit head, during installation, the hold down gag of drilling is enclosed within on the cylinder outer wall of unit head 21 automatically, needs shimming to regulate therebetween, and the pressure foot axis is overlapped with the main-shaft axis of unit head 21.The lower surface of Connection Block 20 is close in the upper surface of pressure foot, has limited pressure foot radially sliding with respect to unit head 21 in compaction process.
Referring to Fig. 4, the job step of present embodiment is:
Step 1: adopt the MOTOMAN MH50 of company type six coordinate mechanical arms 23 carry SFB type pneumatic type unit heads 21 as the automatic drilling platform, the hold down gag of automatic drilling is fixedly mounted on the unit head 21.After system started, pressure foot moved to the appointment bore position with six coordinate mechanical arms, 23 ends, made point a certain to be holed on to be processed 22 of the drill bit, and the rubber sheet gasket 8 that makes pressure foot apart from surface of the work 2 ~ 3 ㎝ about;
Step 2: six coordinate mechanical arms 23 drive pressure foot and descend along direction of normal to be holed; Pressure foot at first contacts with workpiece 22 surfaces; Along with continuing to press down; Thrust increases gradually, until axle 3 touching limit switches 13, sends pulse enable signal six coordinate mechanical arms 23 to the control system after the predetermined thrust of arrival and stops to press down;
Step 3: the main shaft of unit head 21 is started working, and stretches out in the guide hole 10 of drill bit from head 9, is retracted into original position behind the drilling workpiece 22.
Step 4: six coordinate mechanical arms 23 drive pressure foot and lift, and are back to original position, and drilling finishes.

Claims (4)

1. the hold down gag of an automatic drilling is characterized in that: comprise fixed cover, sleeve pipe, axle, compression spring, stop nut, head, limit switch, installing ring,
The fixed cover symmetry is installed on the unit head outer wall of cylinder block; One end of two sleeve pipes lays respectively in the fixed cover installing hole, is connected with the fixed cover installing hole, and limit switch is positioned at the sleeve pipe middle part to be fixed through installing ring; Compression spring is fixed on the other end end face of sleeve pipe, and axle is passed sleeve pipe and compression spring, and the compression spring other end is fixed through the catch and the stop nut that are enclosed within on the axle; Axle is connected through hold-down nut and head.
2. the hold down gag of automatic drilling according to claim 1; It is characterized in that: said fixed cover is a semi-round ring shape, and respectively there is a lug with holes at two ends, and there is outstanding square cylinder middle part, the semicircular ring outside; Cylinder is provided with installing hole, near leaded hole on the hole wall of installing hole bottom.
3. the hold down gag of automatic drilling according to claim 1, it is characterized in that: said sleeve pipe is the hollow circular-tube structure, and end is circular hole, the diameter of circular hole is less than casing inner diameter, is provided with pressure compensation opening near the casing wall of end.
4. the hold down gag of automatic drilling according to claim 1; It is characterized in that: said head is conical boss, and there is guide hole at the boss center, and there is screw linkage section end, boss both sides; Be provided with ribs between linkage section and boss, glued joint rubber sheet gasket and head lower surface.
CN2012103056885A 2012-08-27 2012-08-27 Automatic drilling compressing device Pending CN102814529A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN2012103056885A CN102814529A (en) 2012-08-27 2012-08-27 Automatic drilling compressing device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN2012103056885A CN102814529A (en) 2012-08-27 2012-08-27 Automatic drilling compressing device

Publications (1)

Publication Number Publication Date
CN102814529A true CN102814529A (en) 2012-12-12

Family

ID=47299174

Family Applications (1)

Application Number Title Priority Date Filing Date
CN2012103056885A Pending CN102814529A (en) 2012-08-27 2012-08-27 Automatic drilling compressing device

Country Status (1)

Country Link
CN (1) CN102814529A (en)

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103103698A (en) * 2012-12-31 2013-05-15 天津应大股份有限公司 Positioning drilling machine
CN104802314A (en) * 2015-04-18 2015-07-29 成都扬中新能源科技有限公司 Mechanism for facilitating optimization of drilling quality of mica plate
CN104802315A (en) * 2015-04-18 2015-07-29 成都扬中新能源科技有限公司 Pre-stressed drilling machine
CN104827579A (en) * 2015-04-18 2015-08-12 成都扬中新能源科技有限公司 Mica material hole processing quality enhancement facilitating device
CN105414667A (en) * 2015-11-30 2016-03-23 诸暨市润拓机械自动化科技有限公司 Chamfering mechanism
CN105930569A (en) * 2016-04-15 2016-09-07 上海交通大学 Pressing force adjustment method for controlling inter-drill-layer burr of laminated plate
CN107378072A (en) * 2017-07-31 2017-11-24 深圳利工科技有限公司 A kind of numeric control drilling machine tool bores the spacing pressure-keeping mechanism of start and stop of rifle guide pin bushing
CN110281037A (en) * 2019-06-28 2019-09-27 航天神舟飞行器有限公司 A kind of measurement processing execution head suitable for aircraft skin drilling
CN110587828A (en) * 2019-09-30 2019-12-20 江苏金斗云新型材料科技有限公司 Building slabstone drilling equipment
CN111842972A (en) * 2020-07-28 2020-10-30 沈阳航空航天大学 A location support auxiliary fixtures that is used for accurate drilling on aircraft
CN112453464A (en) * 2020-11-25 2021-03-09 杭州鼎友五金机械制造有限公司 Metal piece high-precision drilling equipment and working method thereof
CN112453463A (en) * 2020-11-25 2021-03-09 杭州鼎友五金机械制造有限公司 High-precision drilling equipment for metal parts
CN114103226A (en) * 2021-09-30 2022-03-01 武汉海王新能源工程技术有限公司 Super press

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0117527A2 (en) * 1983-02-25 1984-09-05 Reinhard Becher Drilling aid
GB2294653A (en) * 1994-11-04 1996-05-08 Michael John Clarke Side mounted drill guide
JPH10175107A (en) * 1996-12-13 1998-06-30 Sanko Techno Kk Jig for boring drill and boring drill
ZA981108B (en) * 1997-03-03 1998-08-20 Cembre Spa Drill for drilling crossties particularly for use in the railroad sector
CN200991778Y (en) * 2007-01-13 2007-12-19 中国科学院安徽光学精密机械研究所 Pistol driller control holder
KR100906532B1 (en) * 2007-05-11 2009-07-07 백문현 Drill stand
CN102303261A (en) * 2011-06-17 2012-01-04 南京航空航天大学 Self-adapting fine-tuning device for pressure foot of automatic drill-rivet end effector
CN102513580A (en) * 2012-01-06 2012-06-27 南京航空航天大学 Device and method capable of reducing interlayer burrs during making holes for aircraft assembly
CN202845849U (en) * 2012-08-27 2013-04-03 西北工业大学 Compressing device for automatically drilling

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0117527A2 (en) * 1983-02-25 1984-09-05 Reinhard Becher Drilling aid
GB2294653A (en) * 1994-11-04 1996-05-08 Michael John Clarke Side mounted drill guide
JPH10175107A (en) * 1996-12-13 1998-06-30 Sanko Techno Kk Jig for boring drill and boring drill
ZA981108B (en) * 1997-03-03 1998-08-20 Cembre Spa Drill for drilling crossties particularly for use in the railroad sector
CN200991778Y (en) * 2007-01-13 2007-12-19 中国科学院安徽光学精密机械研究所 Pistol driller control holder
KR100906532B1 (en) * 2007-05-11 2009-07-07 백문현 Drill stand
CN102303261A (en) * 2011-06-17 2012-01-04 南京航空航天大学 Self-adapting fine-tuning device for pressure foot of automatic drill-rivet end effector
CN102513580A (en) * 2012-01-06 2012-06-27 南京航空航天大学 Device and method capable of reducing interlayer burrs during making holes for aircraft assembly
CN202845849U (en) * 2012-08-27 2013-04-03 西北工业大学 Compressing device for automatically drilling

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103103698A (en) * 2012-12-31 2013-05-15 天津应大股份有限公司 Positioning drilling machine
CN104802314A (en) * 2015-04-18 2015-07-29 成都扬中新能源科技有限公司 Mechanism for facilitating optimization of drilling quality of mica plate
CN104802315A (en) * 2015-04-18 2015-07-29 成都扬中新能源科技有限公司 Pre-stressed drilling machine
CN104827579A (en) * 2015-04-18 2015-08-12 成都扬中新能源科技有限公司 Mica material hole processing quality enhancement facilitating device
CN105414667B (en) * 2015-11-30 2019-08-20 诸暨市润拓机械自动化科技有限公司 Chamfer mechanism
CN105414667A (en) * 2015-11-30 2016-03-23 诸暨市润拓机械自动化科技有限公司 Chamfering mechanism
CN105930569A (en) * 2016-04-15 2016-09-07 上海交通大学 Pressing force adjustment method for controlling inter-drill-layer burr of laminated plate
CN105930569B (en) * 2016-04-15 2019-04-19 上海交通大学 Control the pressing force method of adjustment of laminated plate drilling interlayer burr
CN107378072A (en) * 2017-07-31 2017-11-24 深圳利工科技有限公司 A kind of numeric control drilling machine tool bores the spacing pressure-keeping mechanism of start and stop of rifle guide pin bushing
CN110281037A (en) * 2019-06-28 2019-09-27 航天神舟飞行器有限公司 A kind of measurement processing execution head suitable for aircraft skin drilling
CN110281037B (en) * 2019-06-28 2021-09-03 航天神舟飞行器有限公司 Measurement processing execution head suitable for aircraft skin hole making
CN110587828A (en) * 2019-09-30 2019-12-20 江苏金斗云新型材料科技有限公司 Building slabstone drilling equipment
CN111842972A (en) * 2020-07-28 2020-10-30 沈阳航空航天大学 A location support auxiliary fixtures that is used for accurate drilling on aircraft
CN112453464A (en) * 2020-11-25 2021-03-09 杭州鼎友五金机械制造有限公司 Metal piece high-precision drilling equipment and working method thereof
CN112453463A (en) * 2020-11-25 2021-03-09 杭州鼎友五金机械制造有限公司 High-precision drilling equipment for metal parts
CN114103226A (en) * 2021-09-30 2022-03-01 武汉海王新能源工程技术有限公司 Super press

Similar Documents

Publication Publication Date Title
CN102814529A (en) Automatic drilling compressing device
CN202845849U (en) Compressing device for automatically drilling
CN102513839B (en) Drilling device of flange face bolt
CN105840126A (en) Linked-release hanger delivery tool
CN107380478A (en) A kind of method for optimizing technique for aircraft composite component assembly binding face gap
CN104708088A (en) Method and clamping device for automatic compressing of drilling and reaming parts of porous precise drilling and reaming clamping device
CN202087865U (en) Drilling device
CN102059369B (en) Feeding drill applicable to quick change arrangement of joint of robot
CN203567365U (en) Pneumatic marking machine convenient for handling
CN101966601A (en) Template device for drilling holes on crankshaft flange end face
CN203470972U (en) Drill jig tool for mounting holes of automobile panel
CN202877559U (en) Cutter frame structure of vertical lathe
CN203696544U (en) Taper shank converting sleeve for machine tool spindle
CN110449954A (en) Vertical cabin class flexible part frock clamp
CN205520450U (en) Container automatic drilling machine
CN206253881U (en) A kind of connecting rod and Machining of Connecting Rod equipment
CN108482705B (en) Eight-foot crawling robot pressure angle posture control mechanism
CN203541564U (en) Balanced oil cylinder device of vertical lathe
CN206812062U (en) A kind of elastic gum wing topping machanism of oil steering tool centralizer
CN202045523U (en) Device for processing pin hole of piston skirt
EP3221069B1 (en) Device and method for mechanical working
CN215240444U (en) Workpiece pressing device and workpiece positioning system
CN204591181U (en) A kind of oil drilling floating chuck
CN209491992U (en) Multiple groups rope saw elevating screw mounting structure
CN105728797A (en) Drilling clamp for threaded bottom hole of square part

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
C02 Deemed withdrawal of patent application after publication (patent law 2001)
WD01 Invention patent application deemed withdrawn after publication

Application publication date: 20121212