- Email: [email protected]
Engineering components listed in short-form catalogue
|o
Pltl (l$ Design of n fibre-optic holographic system Fibre-optic interferometers can offer benefits with regard to their insensitivityto vibration and misalignment, their ability to withstand hostile environments and their use in otherwise inaccessible environments. Workers at the University of Kent, UK, have now published details of a fibre-optic holographic system which, they claim, shares many of these advantages.* The functions of all the optical components conventionally used to produce holograms such as beam splitters, mirrors and beam expanding spatial filters - - are performed with single-mode optical fibres, The beam splitter of earlier designs has been replaced by a fibreoptic directional coupler which requires no optical alignment after manufacture and reduces the stringency of the condition for systern stability. The team have also designed an electronic servo system which provides compensation for thermally induced phase shifts. This compensated system (shown in the diagram) was used to produce holograms of high reconstruction efficiency using optical powers launched into the input fibre of up to 500 mW. Exposure times from 20 ms to 200 s were used and the servo system was shown to operate satisfactorily. Holograms were reconstructed using a length of singlemode optical fibre in place of a conventional spatial filter. D.A. Jackson, Department of Physics, The University of Kent, Canterbury, Kent cm2 7NR, UK * Details of the system were published in the following paper in J.Phys.E. : S c i e n tific Instruments: Jones J.D.C., Corke M., Kersey A.D. and Jackson D.A. Singlemode fibre-optic holography. J. Phys. E: Sci. Instrum., 1984, 17 (4), 271-273
Low-cost flatness calibration Inexperienced personnel can carry out a precise calibration and verification of flatness within minutes using the Surfsure package from CD Measurements, it is claimed. The package was developed in collaboration with the University of Manchester Institute of Science and Techology, UK, and can be used
170
"pz Beam ~splitter ~ , ~ / ~ k\j~ererence beam ~ -'t- .,,_\ Objectbeam Object ~ ~"----~/ ~__%,-~ -: ~__ I \ ~'~ ~ m ode I \/=~/"-. X# \ fibre I \ / "" .4¢f~-~ Plate I \ . - '~._ \ _ [Photodlodes
~=~uncher Loser Directional coupler
Compensated system for fibre-optic holography: Input fibres with lengths from 3 to 10 m between the laser and directional coupler were used; the reference and object beam fibres were each about 1 m long. The laser was mounted on a separate optical table from the other components (after Jones, Corke, Kersey and Jackson)
with Talyvel or Syler electronic levels, The system incorporates an Acorn 'BBC' microcomputer; user friendly software is stored inside the computer rom and is instantly available. Automatic calibration mode can be selected, and both 'Union Jack' and rectangular grid measuring procedures can be followed. Flatness results are specified in terms of the BS 817 (1983) tolerance grades in either metric or imperial units. Test certificates of the results are produced on a graphics printer in both pictorial and numerical form. M. Burdekin, CD Measurements, Chomlea House, Hadfield Road, Hadfield, Hyde, Cheshire SK14 8ER, UK
micropositioning stage
X~Z
Changes in design approach have improved the performance of integral 3-axis positioning stages from Newport. By using a larger, select grade of ball bearing, the movement is somewhat smoother and the wear on the lapped and hardened ways is
greatly reduced. A design which does not depend on spring tension for support gives the stages a high load-carrying capacity in the vertical direction. 460-XYZ positioning stages offer precise, rectilinear motion with runouts below 0.0001 inch per inch of travel, says Newport. They are compact and offer 0.5 inch travel along each axis. Optional motorized
positioners, differential micrometers or ultrafine adjustment screws may be ordered instead of the standard micrometers. USA domestic price for the 460-XYZ is $547; delivery is from stock. Newport Corporation, PO Box 8020, Fountain Valley, CA 927288020, USA
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I
= = . =
,
The mode/460 micropositioning stage from Newport is also available in X, XY and XZ versions.
Engineering components listed in short-form catalogue In a 16-page short-form catalogue, Unimatic Engineers list their complete product range. The products include motors of all types along with their associated electronics, geared and encoder-motors, gearboxes, variable speed drives, encoders, linear actuators, linear
JULY 1 9 8 4 V O L 6 NO 3
|'
PItE¢t$ bearings, linear slides, linear and XYcoordinate tables, ballscrews, rotary tables, optical equipment, granite benches, and metrology equipment, Unimatic Engineers Ltd, Grinville Road Works, 122 Granville Road, London NW2, UK
Real time correction of bore geometrydaring l_.,
_
ilonlng Flexible automatic machining systerns are being introduced throughout industry in the drive to produce consistent, accurate parts with maximum added value. Automatic correction in real time has been made possible by developments in control systems, cutting tools, workhandling equipment, in-process gauging and tool wear compensation. At least one operation, however, honing - - often the last and most critical operation --still remains dependent to a large extent on manual surveillance and intervention to maintain quality, In honing continual adjustments are necessary to accommodate variations arising from previous machining operations. With the Autoform system from Citroen Industrie, the bore is scanned during the honing operation using air jets. Signals fed back from the gauging unit to the microprocessor in the control systern allow it to analyse and monitor the bore geometry continuously, Corrective information is then fed back to modify the stroke to remedy any inaccuracies, For example, should the gauging unit detect a negative taper, the machine will execute a short stroke cycle at the top of the bore until parallelism is restored, Similarly, detection of a positive taper results in a short stroke cycle at the bottom of the bore. Should the profile bulge in the middle, the stroke will be concentrated in this area. Short-stroke cycles are punctuated at frequent intervals by a full stroke to check the whole bore geometry. As soon as the control senses the deformation has been corrected, the machine reverts to the normal full-stroke pattern, with continuous scanning to ensure the required geometry is maintained. An additional benefit claimed for Autoform is its ability to dwell at the bottom of the stroke to enable deformations to be removed from engine blocks with caps fitted which
PRECISION ENGINEERING
normally inhibit defect removal by limiting stroke. When the deformation is corrected by the dwell the machine will finish with full length strokes to re-establish the cross hatch pattern on the cylinder wall. Autoform can be fitted to the full range of Citroen honing machines, which are capable of producing precision bores from 3 to 200 mm diameter. They are used in the manufacture of fuel injection equipment, components for hydraulics systems, cylinder blocks and liners for the automotive industry, and in the engineering industries generally. Citroen Industrie UK, York House, Clarendon Avenue, Leamington Spa, Warwickshire CV325PP, UK.
siderations, together with honing head designs, and the use of diamond and cbn abrasives. Also considered are surface finish, tool preparation, and tool life as well as the type of coolants used. A number of case histories are included. Copies of the paper, which includes a number of half-tones graphs, diagrams and tables, can be obtained free of charge from De Beers Industrial Diamond Division (Pty) Ltd, Charters, Sunninghill, Ascot, Berkshire SL5 9PX, UK.
Honingwith diamond and
Loading/unloading times for lapping can be reduced through the use of a drop table. Larger Lapmaster machines have incorporated this facility for some time, but it has now been extended to the small Lapmaster 15 lapping machine. Movement of rings on and off the lap plate is achieved by raising or lowering the work table. During normal running the work table is positioned slightly below the lap plate. At the end of the lapping cycle the fully loaded rings of lapped cornponents can easily be slid on to the work table. The work table is then raised again to allow replacement, fully loaded rings of unlapped cornponents to slide on to the lap plate. Lapmaster International Ltd, Lee Mill Industrial Estate, Ivybridge, Devon PL21 9EN, UK
cbn abrasives
Many modern honing machines are designed around the use of diamond and cbn tooling and it is the use of these ultrahard abrasives which, according to De Beers, largely explains present substantial growth in honing machine sales. A recent technical paper* by H.O. Juchem of De Beers Industrie-Diamanten (Deutschland) GmbH, D(Jsseldorf, provides an interesting study of the honing process and the parameters affecting performance, The ten-page paper discusses the honing motion and infeed con*JuchemH.O. H o n i n g with diamond and cbn abrasives. Industrial Diamond Review,1984,44 (4), 209-218
.....
Lapping machine drop
table s a v e s
p = ,.-ro~uc*=on
time
.......
The Lapmaster 15 with drop table
171
Pltl (l$ Design of n fibre-optic holographic system Fibre-optic interferometers can offer benefits with regard to their insensitivityto vibration and misalignment, their ability to withstand hostile environments and their use in otherwise inaccessible environments. Workers at the University of Kent, UK, have now published details of a fibre-optic holographic system which, they claim, shares many of these advantages.* The functions of all the optical components conventionally used to produce holograms such as beam splitters, mirrors and beam expanding spatial filters - - are performed with single-mode optical fibres, The beam splitter of earlier designs has been replaced by a fibreoptic directional coupler which requires no optical alignment after manufacture and reduces the stringency of the condition for systern stability. The team have also designed an electronic servo system which provides compensation for thermally induced phase shifts. This compensated system (shown in the diagram) was used to produce holograms of high reconstruction efficiency using optical powers launched into the input fibre of up to 500 mW. Exposure times from 20 ms to 200 s were used and the servo system was shown to operate satisfactorily. Holograms were reconstructed using a length of singlemode optical fibre in place of a conventional spatial filter. D.A. Jackson, Department of Physics, The University of Kent, Canterbury, Kent cm2 7NR, UK * Details of the system were published in the following paper in J.Phys.E. : S c i e n tific Instruments: Jones J.D.C., Corke M., Kersey A.D. and Jackson D.A. Singlemode fibre-optic holography. J. Phys. E: Sci. Instrum., 1984, 17 (4), 271-273
Low-cost flatness calibration Inexperienced personnel can carry out a precise calibration and verification of flatness within minutes using the Surfsure package from CD Measurements, it is claimed. The package was developed in collaboration with the University of Manchester Institute of Science and Techology, UK, and can be used
170
"pz Beam ~splitter ~ , ~ / ~ k\j~ererence beam ~ -'t- .,,_\ Objectbeam Object ~ ~"----~/ ~__%,-~ -: ~__ I \ ~'~ ~ m ode I \/=~/"-. X# \ fibre I \ / "" .4¢f~-~ Plate I \ . - '~._ \ _ [Photodlodes
~=~uncher Loser Directional coupler
Compensated system for fibre-optic holography: Input fibres with lengths from 3 to 10 m between the laser and directional coupler were used; the reference and object beam fibres were each about 1 m long. The laser was mounted on a separate optical table from the other components (after Jones, Corke, Kersey and Jackson)
with Talyvel or Syler electronic levels, The system incorporates an Acorn 'BBC' microcomputer; user friendly software is stored inside the computer rom and is instantly available. Automatic calibration mode can be selected, and both 'Union Jack' and rectangular grid measuring procedures can be followed. Flatness results are specified in terms of the BS 817 (1983) tolerance grades in either metric or imperial units. Test certificates of the results are produced on a graphics printer in both pictorial and numerical form. M. Burdekin, CD Measurements, Chomlea House, Hadfield Road, Hadfield, Hyde, Cheshire SK14 8ER, UK
micropositioning stage
X~Z
Changes in design approach have improved the performance of integral 3-axis positioning stages from Newport. By using a larger, select grade of ball bearing, the movement is somewhat smoother and the wear on the lapped and hardened ways is
greatly reduced. A design which does not depend on spring tension for support gives the stages a high load-carrying capacity in the vertical direction. 460-XYZ positioning stages offer precise, rectilinear motion with runouts below 0.0001 inch per inch of travel, says Newport. They are compact and offer 0.5 inch travel along each axis. Optional motorized
positioners, differential micrometers or ultrafine adjustment screws may be ordered instead of the standard micrometers. USA domestic price for the 460-XYZ is $547; delivery is from stock. Newport Corporation, PO Box 8020, Fountain Valley, CA 927288020, USA
nB
I
= = . =
,
The mode/460 micropositioning stage from Newport is also available in X, XY and XZ versions.
Engineering components listed in short-form catalogue In a 16-page short-form catalogue, Unimatic Engineers list their complete product range. The products include motors of all types along with their associated electronics, geared and encoder-motors, gearboxes, variable speed drives, encoders, linear actuators, linear
JULY 1 9 8 4 V O L 6 NO 3
|'
PItE¢t$ bearings, linear slides, linear and XYcoordinate tables, ballscrews, rotary tables, optical equipment, granite benches, and metrology equipment, Unimatic Engineers Ltd, Grinville Road Works, 122 Granville Road, London NW2, UK
Real time correction of bore geometrydaring l_.,
_
ilonlng Flexible automatic machining systerns are being introduced throughout industry in the drive to produce consistent, accurate parts with maximum added value. Automatic correction in real time has been made possible by developments in control systems, cutting tools, workhandling equipment, in-process gauging and tool wear compensation. At least one operation, however, honing - - often the last and most critical operation --still remains dependent to a large extent on manual surveillance and intervention to maintain quality, In honing continual adjustments are necessary to accommodate variations arising from previous machining operations. With the Autoform system from Citroen Industrie, the bore is scanned during the honing operation using air jets. Signals fed back from the gauging unit to the microprocessor in the control systern allow it to analyse and monitor the bore geometry continuously, Corrective information is then fed back to modify the stroke to remedy any inaccuracies, For example, should the gauging unit detect a negative taper, the machine will execute a short stroke cycle at the top of the bore until parallelism is restored, Similarly, detection of a positive taper results in a short stroke cycle at the bottom of the bore. Should the profile bulge in the middle, the stroke will be concentrated in this area. Short-stroke cycles are punctuated at frequent intervals by a full stroke to check the whole bore geometry. As soon as the control senses the deformation has been corrected, the machine reverts to the normal full-stroke pattern, with continuous scanning to ensure the required geometry is maintained. An additional benefit claimed for Autoform is its ability to dwell at the bottom of the stroke to enable deformations to be removed from engine blocks with caps fitted which
PRECISION ENGINEERING
normally inhibit defect removal by limiting stroke. When the deformation is corrected by the dwell the machine will finish with full length strokes to re-establish the cross hatch pattern on the cylinder wall. Autoform can be fitted to the full range of Citroen honing machines, which are capable of producing precision bores from 3 to 200 mm diameter. They are used in the manufacture of fuel injection equipment, components for hydraulics systems, cylinder blocks and liners for the automotive industry, and in the engineering industries generally. Citroen Industrie UK, York House, Clarendon Avenue, Leamington Spa, Warwickshire CV325PP, UK.
siderations, together with honing head designs, and the use of diamond and cbn abrasives. Also considered are surface finish, tool preparation, and tool life as well as the type of coolants used. A number of case histories are included. Copies of the paper, which includes a number of half-tones graphs, diagrams and tables, can be obtained free of charge from De Beers Industrial Diamond Division (Pty) Ltd, Charters, Sunninghill, Ascot, Berkshire SL5 9PX, UK.
Honingwith diamond and
Loading/unloading times for lapping can be reduced through the use of a drop table. Larger Lapmaster machines have incorporated this facility for some time, but it has now been extended to the small Lapmaster 15 lapping machine. Movement of rings on and off the lap plate is achieved by raising or lowering the work table. During normal running the work table is positioned slightly below the lap plate. At the end of the lapping cycle the fully loaded rings of lapped cornponents can easily be slid on to the work table. The work table is then raised again to allow replacement, fully loaded rings of unlapped cornponents to slide on to the lap plate. Lapmaster International Ltd, Lee Mill Industrial Estate, Ivybridge, Devon PL21 9EN, UK
cbn abrasives
Many modern honing machines are designed around the use of diamond and cbn tooling and it is the use of these ultrahard abrasives which, according to De Beers, largely explains present substantial growth in honing machine sales. A recent technical paper* by H.O. Juchem of De Beers Industrie-Diamanten (Deutschland) GmbH, D(Jsseldorf, provides an interesting study of the honing process and the parameters affecting performance, The ten-page paper discusses the honing motion and infeed con*JuchemH.O. H o n i n g with diamond and cbn abrasives. Industrial Diamond Review,1984,44 (4), 209-218
.....
Lapping machine drop
table s a v e s
p = ,.-ro~uc*=on
time
.......
The Lapmaster 15 with drop table
171