James Richmond09/09/20101 CLIC Permanent Magnet Quadrupole - Proposed Mechanism Prepared by James Richmond Presented by Norbert Collomb STFC Daresbury Laboratory

09/09/2010James Richmond2 Solution 1 – Double Drive Solution 2 – Single Drive Solution Overview/ Common Features Contents Module Integration Summary/Questions

09/09/2010James Richmond3 Solutions Overview o Both solutions use latest magnet configuration (40º PM’s with the addition of ‘sandwich plate’) o Mechanism allows PM to move 68mm and therefore achieve the gradient range as specified o Where possible, high rigidity and low backlash components have been utilised in order to deliver the highest accuracy and precision possible o Manufacturability and repeatability have also been considered throughout the design

09/09/2010James Richmond4 Common Magnet Components – ‘Sandwich Plate’ o In light of a meeting with a permanent magnet manufacturer, concerns were raised with the magnets being in pure tension o In order to stop this, a ferritic plate was added to ‘sandwich’ the PM and therefore reduce this issue

09/09/2010James Richmond5 Common Magnet Components – Spring Steel Straps o The plate would be held in place with 3 spring steel straps that would be pre- tensioned and fixed in 3 places. Strap positions have been optimised using FEA o Finite Element Analysis suggested the PM’s need support. The bottom strap fixture acts as this support

09/09/2010James Richmond6 Common Mechanical Features – Ball Screw Arrangement o 2 Precision ball screw assemblies are driven with a motor and gearbox arrangement 2 Thrust Bearings will take the high axial loads while also removing any radial displacement and enable fine adjustment when assembling Anti backlash gearbox and couplings ensure minimum play in system o Based on magnetic modelling, calculations could be carried out in order to determine torques involved. From these results, motor and gears have been specified following calculations to determine torque o Power to the motor will accurately rotate lead screw (LH +RH Thread) resulting in opposite motion of the nuts

09/09/2010James Richmond7 Common Mechanical Features – Liner Motion Guide o 8 ‘Off the shelf’ linear motion guides will be used to ‘steer’ the system effectively 2 pre-loaded blocks on each rail help take the moments produced by the high loads o Low sectional height offers high rigidity and therefore achieves highly accurate and stable linear motion o Self adjusting blocks capable of easily absorbing an accuracy error in parallelism and level between the rails Stainless steel rail option for low magnetic permeability

09/09/2010James Richmond8 Solution 1 – Double Drive o 2 motors with 2 in-line gearboxes will drive the system Advantages o Double drive makes for an easier assembly with less alignment issues Disadvantages o Double drive allows potential discrepancy in the 2 systems o Less components to introduce backlash and therefore only 2 couplings needed o Readily available ‘off the shelf’ components Mass approx. 76kg o Increased height due to inline gearbox/motor Fully Open Half Open Closed

09/09/2010James Richmond9 Dimensions mm 262mm 695 mm 385 mm Spec. (391 x 391 x 270) mm 230mm magnet Bolt Radius 74mm

09/09/2010James Richmond10 It can be seen, that although outside the envelope, the proposed system fits the module without interfering with any of the surrounding components – To be confirmed

09/09/2010James Richmond11 Solution 2 – Single Drive o 1 motor with 2 right angle and a ‘T’ gearbox Advantages o Single drives potentially eliminates any discrepancy in the 2 systems without the use of encoders Disadvantages o Potentially more backlash in the system o A smaller and more compact solution (motor overhang) o Components are no longer necessarily ‘off the shelf’ Mass approx. 78kg o Requires larger amount of alignment features o Simpler system control Fully Open Half Open Closed

09/09/2010James Richmond12 Dimensions mm 262mm 654 mm 385 mm Spec. (391 x 391 x 270) mm 230mm magnet Bolt Radius 74mm 319mm

09/09/2010James Richmond13 Again, solution 2 fits the module without interfering with any of the surrounding components – To be confirmed and overhang side discussed

09/09/2010James Richmond14 Assembly Concerns Overall Assembly Accuracy Diamond dowels will help align core components by eliminating degrees of freedom PM Alignment Wedge could be clamped in centre during assembly in order to align PM’s

09/09/2010James Richmond15 Assembly Concerns Slotted brackets could be used to allow adjustment on assembly Motor/Gearbox Alignment (solution 2) Safe Assembly Bespoke tooling required to safely and accurately assemble magnetic components

09/09/2010James Richmond16 Future Development o Finite Element Analysis of structural components to validate and optimise design, i.e. reduce part count (Sept 2010) o Development of Assembly plan along with required tooling (Nov 2010) o Design Evaluation – i.e. functionality, materials, processing, detailing (Oct 2010) o Procurement (Jan 2011) o Costing (Dec 2010) o Testing o Integration into module(s) (Oct 2010) o Prototyping (April 2011)

09/09/2010James Richmond17 Summary o Two viable solutions have been designed that offer accurate and repeatable linear displacement of the permanent magnets o Both solutions meet the magnetic specification o Methods need to be designed to ensure, safe, accurate and repeatable assembly o Although outside the envelope, the proposed systems fit the module without interfering with any of the surrounding components - Point of discussion o Similar drive systems have been used many times before at STFC and prove to be reliable o Dialogue with manufacturers have been instigated

09/09/2010James Richmond18 Questions?

09/09/2010James Richmond19

09/09/2010James Richmond20 Part Specification (Solution 2) Manufacturer Model No. TypeOther Shaft Diameter (mm) Lead (mm/rev) Ball-to- Ball Diameter (mm) End Type THKBIF Precision Ball Screw Pre Loaded H1 Ball Screw x4 (or x2 LH+RH) ManufacturerModel No.TypeOther Shaft Diameter (mm) THKEK15Square Type Support Unit Fixed Side20 Thrust Bearing x4

09/09/2010James Richmond21 Manufacturer Model No. TypeOther Block Dimensions H x W x L (mm) Rail Dimensions W x L (mm) Comments THKSR 15 SB M LM GuideRadial Type Stainless Steel 24 x 52 x x 185 Fixture type may need changing i.e SB to V Linear Motion Guide (x8 Rail + x16 Block) ManufacturerModel No.TypeOther Steps (steps/rev) Dimensions H x W x L (mm) Shaft Diameter (mm) McLennan23HSX Hybrid Stepper Motor Optional Encoder x 57.2 x Motor x1

09/09/2010James Richmond22 ManufacturerModel No.TypeOther Shaft Diameter (mm) Ratio Comments OndriveDTR60S-025Right Angled Gear head Low Backlash1625:1Contact On-Drives for variable shaft length and male input Right Angle Gearbox x2 ManufacturerModel No.TypeOther Shaft Diameter (mm) Ratio Shaft Arrangement Comments OndriveVP75L0-0Spiral Bevel Power Gearbox Low Backlash 162:113Contact On-Drives for variable shaft length ‘T’ Gearbox x1 ManufacturerModel No.Type Static Break Torque (Nm) Coupling Size Diameter (mm) Max Bore (mm) Comments HUCOHub (234.41) Disc (236.41) Blind Oldham Couplings To order a complete coupler you must order TWO hubs and ONE disc Couplings x5