Minutes BWS Upgrade: Electro-Mechanical Design Meeting #2 -- 24th July 2015 --
Participants: Bernd Dehning, Raymond Venness, Dmitry Gudkov, Jonathan Emery, Pierre-Jean Lapray, Luca Timeo, Jose Luis Sirvent
Agenda ( http://indico.cern.ch/event/435233/
) :
PDF version here
1. Communications
- The new optical disk fixation has been tested, observed imperfections on holder, the piece needs to be re-machined.
2. Follow-up Open Actions
- No remarks on follow-up open actions
3. Motor Selection (D.Gudkov)
- From 6 Companies contacted for motor procurement 3 are interested (Alxion, Kollmorgen, Parker)
- Quotation from Alxion and Kollmorgen available, waiting for updated Parker quotation.
- 4 Possible motors compliant with our specifications
- Alxion: 14S5TX2M (short) & 14S5TK4M (long)
- Kollmorgen: KBM-35x02
- Parker: NK620
- Motors delivery times (needed to consider holidays):
- Off the shelf : 7..10 Weeks
- Custom models : 10..16 Weeks
- Main Differences Custom vs Standard:
- Samarium Cobalt magnets (and it’s fixation for vacuum compatibility, no glue)
- Increasement of Air Gap by machining stator (0.5 to 0.7 mm = 5 to 10%torque decrease, info from Alxion)
- Open question: Spares politicy?
- Buy a big amount of spares once VS Trust on companies availability guarantee
- All contacted companies are relatively “Big”, production guaranteed for many years
- Decision not taken here
4. Electrical Requirements and test setups (J.Emery)
- Motor Study:
- Motor 14S5TK4M (long) deeply studied by Jonathan in terms of torke, speed and performance for SPS, LHC and PSB.
- This motor would experience acceleration issues for the LHC configuration .
- Longer active length improves torke.
- Exist two versions of this motor (For torke and for Speed).
- This motor is not suitable for 200rad/s , no torke is achieved at this speed, meaning that constant speed is not guaranteed. However, 140rad/s would be fine (but it’s slowlier than specified for the BWS).
- The motor consists on 12 poles (Initial Parker motor had only 4), which means higher di/dt variations, moreover it has a very high inertia.
- Requirements:
- BWS Prototype:
- A mechanical piece is needed to keep the shaft in “Home position”, acting as angular reference to align properly the fork, motor stator/rotor, resolver, break and optical disk.
- BWS Calibration Bench:
- Both Linear stages must be on the same orientation
- System needs to be properly aligned horizontally (to work on a table)
- Fixation of optical parts needs to be defined.
- Design needs to be reviewed Jonathan & Mechanics
- Proposed the usage of two flanges with identical holes to align Laser system.
5. Test Planning (B.Dehning)
- No remarks on test planning
6. AOB
- Discussion:
- New Optical disk:
- New disk sent in September to CERN (a little sample to check quality)
- Possibility of testing the reflectivity of such disk with the real optical system.
- Check investigations on disks with micro holes.
- Decissions:
- 2 Off the shelf motors + 2 Custom motors to be purchased: Alxion 14S5TX2M & Kollmorgen KBM-35x02.
- Integration with Alxion 14S5TX2M .
- Two test-benches as flexible as “Juan model” needs to be built.
- Tests with original motors and stator machined (bigger air gap) motors to be done
Action |
Asigned to: |
Investigations on optical alignment (flanges with holes) |
William/Jonathan |
Revision of BWS calibration system |
Communication with RF |
Bernd |
Ordering Motors |
Dmitry |
Test-Benches construction |
Topic revision: r3 - 2015-08-04
- unknown