液压夹具设计手册.ppt

,Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,*,Vektek China Representative Office Tel:[phone] Fax:[phone] email:chinasales,Vektek China Representative Office Tel:[phone] Fax:[phone] email:chinasales,Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,*,Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,*,Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,*,Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,*,Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,*,Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,*,Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,*,Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,*,Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,*,Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,*,Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,*,Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,*,液压夹具设计手册,思诚机电,1,Good Fixture Design,Good fixtures position,clamp and support workpieces in the most effective way possible,2,Fixture design,workpiece Example 1,3,Fixture design,process,4,Datum,Fixture design,workpiece datums,5,Fixture design,supporting,6,Fixture design,positioning,7,Fixture design,clamping,8,Fixture design,additional support and clamping,9,Fixture,positioning,supporting and clamping,10,Fixture design,workpiece,Example 2,11,Fixture design,process,12,Fixture design,supporting,13,Fixture design,clamping,X,X,14,Fixture design,clamping,Datum,15,Fixture design,positioning and clamping,16,Fixture design,positioning,supporting&clamping,17,Friction clamping,If clamping using friction only it must be remembered that the coefficient of friction(,)is normally calculated at 0.1,Clamping force F,Reaction force,Total clamping force,=F x,Clamping force F,Reaction force,Total clamping force,=F,Clamping force F,2-3,0,from horizontal,Preferable,18,Friction clamping,If clamping using friction only it must be remembered that the coefficient of friction(,)is normally calculated at 0.1,This can be improved on soft materials(eg.Al)if the clamping piston has enough force to penetrate the workpiece,19,Fixture design,DEFINITION OF A CLAMPING FORCE,The force acting on a workpiece to be clamped,is large enough to hold the workpiece firmly in its given position relative to the cutting tool,against the action of the machining forces,20,Fixture design,CLAMPING FORCES,Mechanical,low cost,relatively low forces,Pneumatic,higher cost,relatively low forces,large components,Hydraulic,higher initial cost,high forces,reliable,small components,21,Mechanical Forces,Maximum clamping force,using standard wrench,Clamping force(kN),Clamping force with extension pieces,as shown,500N torque,=0.1,22,Standard clamping strap,M20 thread,Max.recommended torque 223Nm,Max.clamping force 28kN,Hydraulic swing clamp 6951F-11-21,(page 63,metric catalogue),22 rod,76mm long arm,Max.oil pressure 23 MPa,Clamping force 7.3kN,Force comparison,23,Force comparison,Standard clamping strap,M20 thread,Max.recommended torque 223Nm,Max.clamping force 28kN,Hydraulic swing clamp 6951F-11-21,(page 63,metric catalogue),22 rod,clamping strap,Max.oil pressure 35 MPa,Clamping force 13.7kN,24,Standard clamping strap,M24 thread,Max.recommended torque 383Nm,Max.clamping force 40kN,Hydraulic swing clamp 6951FN-33-21,(page 71,metric catalogue),38 rod,clamping strap,Max.oil pressure 35 MPa,Clamping force 35kN,Force comparison,25,Standard clamping strap,M24 thread,Max.recommended torque 383Nm,Max.clamping force 40kN,Hollow piston cylinder 6921-100 x10,(page 26,metric catalogue),M24 thread,Max.oil pressure 400 bar,Clamping force 101kN,Force comparison,26,Mechanical or Hydraulic?,27,Mechanical or Hydraulic?,50 MPa,Sequence Valve 47-0440-02(J-3),Set at 30 MPa,Cartridge Mount Cylinder(x8),42-1010-04(page F-12),2.5 kN each 50MPa,Threaded Cylinder,42-0010-06(page F-4),3.4 kN 30 MPa,5.7 kN 50 MPa,28,Force diagram,30 MPa,50 MPa,Sequence valve opens,Workpieces,Movement of cylinder,Oil pressure,29,Component&Fixture design,SENSIBLE USE OF FORCE,Sensible introduction of positioning,clamping and supporting forces will enhance the quality of a workpiece,30,Oil supply to fixtures,2 basic methods,through pipes,through gun drilled channels,Method depends on,cost target,complexity of fixture,products being used,31,Oil supply to fixtures,cost comparison,A,:Through pipes using flange type clamps,B,:Through pipes using threaded type clamps,C,:Through gun drilled channels&manifold mounted type clamps,D,:Through gun drilled channels&threaded body type clamps,32,Oil supply to fixtures,cost comparison,A,:Through pipes using,flange type clamps,Relatively easy to manufacture,Fittings weakest part of system,Chip traps,Control fixture,COST 100%,33,Oil supply to fixtures,cost comparison,B,:Through pipes using,threaded type clamps,Less swarf traps,Reduces machining area,Fittings weakest part of system,COST?%,against control fixture,34,Oil supply to fixtures,cost comparison,C,:Through gun drilled channels&manifold mounted type clamps,Maximum component density,Minimum swarf traps,COST?%,against control fixture,35,Oil supply to fixtures,cost comparison,D,:Through gun drilled channels&threaded body type clamps,Maximum component density,Minimum swarf traps,COST?%,against control fixture,36,Oil supply to fixtures,cost comparison,C:Through gun drilled channels&manifold mounted type clamps,98%,B:130%,D:104%,A:100%,37,Hydraulic circuit design,38,Circuit design,39,Cam Cover fixture example,40,Circuit design,41,42,www.ec-fixture example,43,Circuit design,44,45,Getting the oil to the fixture,46,Rotary&Rotary Valve Couplings,47,Rotary Couplings,Used when free passage of oil is required to be distributed on rotary table arrangements,Standard versions of single,twin,four and six passages with/without leakage port,Maximum operating pressure 250/500 bar,When specifying include data on rotation speed,pressure,temperature,media and cycle time,Special designs available on request,48,Twin passage rotary coupling,Use on rotary table with two single acting cylinders,49,Four passage rotary coupling,Use on rotary table with 4 single acting or 2 double acting cylinders,50,Six passage rotary coupling,Use on rotary tables with combination of up to 6 oil feeds ie.6 s/a,3 d/a,2 d/a&2 s/a cylinders,51,Rotary Coupling circuit,Single acting circuit,Double acting circuit,52,Application example,53,Rotary Valve Couplings,Used on rotary table arrangements when loading/unloading of stations is required whilst maintaining clamping pressure on remaining stations,Versions include 5,6,7,8,9&10 stations.,Applications requiring 2,3 or 4 stations use 6&8 stations with unused ports plugged.,Special designs available,Up to 200 bar an accumulator is recommended,above 200 bar it is essential due to internal leakage within the oil return cavity of the unit,54,Rotary valve coupling function,Load station,Unload station,Rotary coupling,Work station,Clamping cylinder,55,Rotary Valve Coupling circuit,Single,acting,Double,acting,56,Application example,57,Coupling units,Quick disconnect couplings,One-hand operation quick disconnect,Coupling units,Automatic coupling systems,Threaded coupling elements,58,Quick Disconnect,Couplings,Max operating pressure 500 bar,One hand operation,Always use dustcaps,Coupling units,59,Coupling Units,Single or double acting,Integral accumulator and pressure gauge,Multi-coupler units available,Coupling units&accumulators,60,Coupling Systems,Always use accumulators on static systems,1,0,temperature difference relates to 10 bar pressure difference,Coupling units&accumulators,61,Threaded coupling elements,62,Breathing,63,What is breathing?,Breathing is the action of single acting cylinders during the spring return part of the component cycle,64,Why breathing has to be made,Excess pressure or vacuum in the spring area changes the spring forces which leads to malfunction,Formation of condensation water promotes rust formation and can lead to a complete failure of the elements,Leakage of hydraulic seals must drain off to exterior without pressure otherwise there will be malfunctions,Dust and chips are retained by sintered metal air filters,Liquids can be drawn through the sintered metal filter,thus the breathing spring area is reduced,a higher excess pressure or vacuum is caused and the function is impaired,65,What is breathing?,What happens during breathing,66,Precautions,Cover,Clamping elements without breather ports can be covered.,Due to high coolant pressure and flow this is not always successful,Consider using double acting elements wherever possible,67,Precautions,Breather hose,Connection of a breather hose is approved if the outlet is sited at a point where no liquid can penetrate,Ensure no fluid traps in hose,68,Precautions,Closed breather system,Spring area is increased by connection of additional closed area.,Electrical die cast boxes are ideal,Volume of additional area should be 10 times the stroke volume of all connected components,69,System bleeding,The system,must always,be free from air,70,Component Design,Components can be of fixed design,71,Component Design,Clamping points can be incorporated into design of component,72,Designed for Clamping,73,Designed for Clamping,74,Inaccessible clamping positions,75,Indirect Clamping,76,Fixture Design,Static fixture,Tombstone,Horizontal machining,77,Fixture Design,78,Fixture Design,79,Remember,FIXTURE DESIGN,Good fixtures position,clamp and support components in the most effective way possible,DEFINITION OF A CLAMPING FORCE,The force acting on a workpiece to be clamped,is large enough to hold the workpiece firmly in its given position relative to the cutting tool,against the action of the machining forces,SENSIBLE USE OF FORCE,Sensible introduction of positioning,clamping and supporting forces will enhance the quality of a workpiece,80,Vektek China Rep.Office,chinasales,81,