1. CLIC Permanent Magnet Dipole Feasibility Proposal
Mechanical Engineering status
N. Collomb
19th March 15

2. Agenda Python Design proposal; sizing Python Design proposal; awareness Python Design proposal option one Python Drive system option one principles Python Design proposal option one; pro - con Python Design proposal option two Python Drive system option two principles Python Design proposal option two; pro – con Conclusion
N. Collomb
19th March 15

3. Python Design proposal; sizing
Component sizing assumptions (0.5m prototype):
Attractive forces (vertical) total: 350kN + 10kN self-weight
Attractive forces horizontal total: 2.5kN (pull on PM)
Position accuracy and precision (motion system): within ±25µm (check!)
Linear motion stroke: 430mm
1mm “air-gap” between Permanent Magnet and Yoke (both; bottom & top)
Relative nose-pole position: within ±10µm
Awareness that some shape modifications are required to Yokes and Permanent Magnet
N. Collomb
19th March 15

4. Python Design proposal; awareness
Points to keep in mind:
Assembly must be possible (stating the obvious)
All components must contain features to permit adjustment during the
assembly process
Linear motion system must be adjustable to allow for manufacturing
discrepancies and assembly based deviations (within tolerance range)
Healthy factor of safety (at least 1.5) must be observed where possible
Forces may require updating; thus component change must be “simple”
Yokes and Permanent Magnet to be kept separate but centralised
N. Collomb
19th March 15

5. Python Design proposal option one
Yokes
(High µ/µ0 steel)
Support Pillars (height adjustable)
PM Block
Aluminium Blocks
Aluminium Back-plate
N. Collomb
19th March 15

6. Python Design proposal option one principles
Aluminium Side-plate
Ball-screw nut bridge
HR-type linear motion rail system
Adjustment pillar recess
Z-section
(6 DOF rail adjustment)
Precision Ballscrew (preloaded)
Bolt Through holes (position to be agreed with PM supplier)
N. Collomb
19th March 15

7. Python Design proposal option one principles
Front and rear held in position using pillar and back-plate with Al-Alloy interconnecting block, Rail above and below and to side (as far away as possible from PM), single motor – dual drive system, LM system as guide (little load), single volume yoke design, PM only supply
Grub-screw adjustment
Fixed End Ball-screw support
34HSX-208 Stepper Motor with rotary encoder
Back-plate and drive brackets
UTR90 Right Angle Gearbox 1:25 ratio
4 HR carriages per side (adjustable)
DTR90H
T-Gearbox through axle
1:2 ratio
N. Collomb
19th March 15

8. All up weight …………wait …………wait …………wait ……3262kg N. Collomb
19th March 15

9. Python Design proposal option one; pro - con
Large component adjustment range to cater for “slack” manufacturing tolerances
No side-plate to support yokes required
Linear Motion system familiarity (Low Strength Quadrupole)
“Off-the-shelf” components such as, LM system, motor & gearboxes and ball-screw and nut
Permanent Magnet is a single item to procure (no subassembly)
Sandwich PM between sturdy side-plate – “large” adjustment & “low” cost
Assembly sequence straight forward
Can cater for larger forces without design change
Can cater for support components and Fiducial markers
Ball-screw top and bottom driven by one motor means synchronised motion
Option for separate curved nose-pole piece exists (1.5m Dipole Sagitta: 56.6mm, Beam R = 5m)
N. Collomb
19th March 15

10. Python Design proposal option one; pro - con
Large component adjustment range means each assembly step requires metrology
Permanent Magnet insertion requires substantial jigs and fixtures
Horizontal yoke adjustment (over and under-bite) limited
Rear of magnet adjustment pillar requires removal after back-plate is fixed
Linear Motion system overhangs yoke – magnetic distortion (symmetric) check!
Large volume yoke may cause procurement and manufacturing issues
Loose tolerances permitted in component manufacture may require post machining
N. Collomb
19th March 15

11. Python Design proposal option two
Yokes
(High µ/µ0 steel)
Support Pillars (height adjustable)
PM Block encased in Alu frame
Separate Nose-pole pieces (High µ/µ0 steel)
Aluminium Side-plate
Connecting Plate, Yokes – Rear-shunt
Rear-shunt
N. Collomb
19th March 15

12. Python Design proposal option two, principles
Front and rear held in position using rear-shunt, connecting-plate and side-plate (Al-Alloy), Rail above and below and to side (as far away as possible from PM), single motor – dual drive system, LM system as guide (little load), split yoke design, PM in frame supply
3 off Support Pillars (height adjustable)
Aluminium Frame with PM bonded and clamped in position
Long Ballscrew with 2 nuts
Carriage saddle (AL-Alloy)
HSR Rail system
N. Collomb
19th March 15

13. Python Design proposal option two; pro - con
Separate Nosepole piece for accurate positioning
No interconnecting block required
Linear Motion system familiarity (High Strength Quadrupole)
“Off-the-shelf” components such as, LM system, motor and gearboxes
PM supplied in frame – no additional assembly required
Can cater for larger forces without too much of a design change (side-plate)
Can cater for support components and Fiducial markers on connecting plate
Ball-screw top and bottom driven by one motor means synchronised motion
Option for separate curved nose-pole piece exists
Can be broken down into convenient subassemblies
N. Collomb
19th March 15

14. Python Design proposal option one; pro - con
Component tolerance needs to be constricted
Permanent Magnet insertion requires substantial jigs and fixtures
Permanent Magnet insertion must occur early on in assembly process
Bonding material may deteriorate – clamping force of frame may cause PM fractures
Pre-assembled systems (connecting plate, ballscrew & saddle) sensitive to misalignment. Same for side-plate and rails
Linear Motion system bridges yoke & rear shunt – magnetic distortion (symmetric)
Nosepole piece adjustment required after rear shunt assembly (with PM in place)
Post machining requirement more likely as component/subassembly adjustment is limited
Rear shunt contributing only very marginally to the magnetic performance
Rather wide (1.9m) and heavy at 4070kg.
N. Collomb
19th March 15

15. Conclusion
The evaluation of the principles applied in option one and two points to a final design making use of features from both.
The rear shunt may not be required, thus the continuation of the yoke (to form a “C”) must be maintained by either the suggested back-plate or shunt shape component.
Preferably no yoke supporting side-plate arrangement should be used.
To keep cost down the Permanent Magnet should be plain as in option 1.
A separate nosepole piece is recommendable to permit fine adjustment if required. Additional benefits are the raw material procurement (common size) and manufacture (closer tolerance).
N. Collomb
19th March 15

16. Conclusion
Using a “pillars and “back-plate” arrangement” to take the attractive force load permits the linear motion system to be kept “small” due to minor load inducement (provided the PM is centrally positioned).
The drive system should be as compact as possible (short and low volume) to minimise magnetic influences.
Assembly process must be safe and sequential, ideally with the PM insertion last.
Support features and Fiducial markers mustn’t interfere with operation and magnetic performance.
N. Collomb
19th March 15

17. CLIC Permanent Magnet Dipole Feasibility Proposal Presentation End
Questions?
N. Collomb
19th March 15

18. Backup images
N. Collomb
19th March 15

19. ISO Front View
ISO Rear View
N. Collomb
19th March 15

20. Plan View
Side View
Front View
N. Collomb
19th March 15