HICIAOAssemblyProcedure

1
HICIAO-Assembly-Procedure
Prepared for HICIAO CDR Author Vern
Stahlberger Institute for Astronomy Date 01-30-06
2
HICIAO Fore-Optics
Main access to inside of Cryostat is via VJ Top
Cover Weight 10 kg
HICIAO Fore-Optics Mounts to AO-Bench
Connectors are mounted on a large Sub-Plate to
facilitate access to cables through the VJ
3 mm clearance between Fore-Optics and VJ
3
AO-Bench Interface Plate (Subaru-design) to
match up with holes on dowel pins to this face
Fore-Optics is decoupled from Vacuum Jacket!
3mm Gap between HICIAO VJ and Fore-Optics Assembly
4
Starting point for HICIAO Assembly Sequence
V-Truss Assembly (Qty4)
VJ Bottom Plate
5
Note Lip on the Optics Bench for Light-Seal
V-Truss Light Shield
Brass Slides Qty3
Optics Bench
Cutouts for Detector Assembly

• Brass Slides permit slight adjustments along the
  optical axis
• For Assembly, use shims in places indicated

Place Shims here
6
Shim Location
Common Path Filter Wheel Assembly (CPFW)
Install Light-Tube-1 to CPFW
Use .344 inch thick shim to locate CPFW to
nominal position place shim between Filter cover
and inside of Optics Bench
7
Pupil Wheel Assembly (PW)
Slide PW up flush against Light-Tube-1
Light-Tube-1
Install Light-Tube-2
8
Add Detector Assembly It must be installed prior
to the Differential Path Filter Wheel (DPFW)
Detector Assembly
Prepare ASIC Flex Ribbon Cable as shown
9
Light-Tube-2
Tongue Light Shield
Bottom out against Light-Tube-2 prior to
inserting DFPW
To keep the Optics Path light tight, a Tongue
Groove design interface is used for the 2 marked
parts the Tongue Light Shield must be inserted
before the DPFW
10
Filter Wheel Case
Once DPFW is installed, bottom out Tongue Light
Shield on Filter Wheel Case and secure with 2
screws
Tongue Light Shield
DPFW
11
Assembly Closed Cycle Cooler and 1st Stage Strap
to Vacuum Jacket
12
9x ¼-20 Socket Head Caps with Washer
1st Stage Strap (compliant)
1st Stage Strap is composed of .12mm thick
Copper Foils and bent into the configuration
shown to cancel out vibrations from the 1050 CTI
Cold Head
13
Clamp type design to secure the 1st Stage Strap
to the Optics Bench screws are located on the
inside of the Optics Bench (previous slide)
14
VJ Lower Body
Hex Socket Head M6 x 25 25 Required
Evacuation Valve Rotates through 360 Deg
Connectors and Connector Sub-Plates should be
installed AFTER the VJ Lower Body has been bolted
in place!
15
Prepare Radiation Shield as shown in this slide
add to Assembly
S.H.C.Vented 6-32 x 5/8 32 Required
16
Radiation Shield without Shield Top Plate
Note This assembly state should be used to wire
up the instrument
17
CTI Cold Finger will slide through the inside of
the Getter Shield
Getter Shield attached to Radiation Shield Tube
1st Stage Strap
18
Vibration Isolation Mount
Closed Cycle Cooler Assembly
1st Strap Access Cover
2nd Stage Getter Assembly
CTI 1050 Cold Head
Safety Finger Qty3
Cold Wire to Detector
CCC Mount Flange
Prior to Vacuum, the CCC Cold Head is loose.
After Vacuum is applied Cold Head is compressing
the 2 Isolation Rings (Rubber) 3 Safety Fingers
limit the motion of the Cold Head with no Vacuum
19
1050 CTI Cooler assembled to Vacuum Jacket
Use these Screws to limit movement of CCC Cold
Head when not under Vacuum 3 Places
Access Hole in CCC Mount Flange used to bolt 1st
Stage Strap to CCC Cold Finger
20
Changing FiltersLenses etc
21
Access Covers to Filter/Lenses
Hall Sensor Mount
This and next slide show state of disassembly
necessary to perform maintenance and change
filters/sensors/lenses etc.
22
View into open Cryostat Entrance Window at Right
23
HICIAO Installation on NASMYTH

• After PDR, Fore-Optics and Vacuum Jacket became 2
  independently mounted assemblies
• Wollaston Prism is close to Vacuum Jacket for
  optical performance reasons
• Must protect Wollaston Prism from possible
  collision with Vacuum Jacket upon installation
• Next slides discuss new design for mounting
  procedure of Fore-Optics and Vacuum Jacket on
  Nasmyth Floor

24
Brief Overview of Installation Procedure1)
Install the Fore-Optics Assembly to the
AO-Interface Plate mounted to AO-Bench2)
Transport HICIAO VJ and Interface Frame to the
site either by Crane of Rail ( Subarus
decision)3) HICIAO VJ must be in the retracted
position!4) Move HICIAO to observing position
using crankThe following slides will explain in
detail the procedure, including initial setup and
alignment.
25
Interlocking Pin Qty2
Side Adjust Bracket Qty4
VJ Bottom Plate
Opt-Axis Adjust Rail Qty2
Foot Focus Adjustment Qty4
Z-Shim Qty4
26

• Comments on previous slide
• The Side Adjust Brackets are used for the initial
  alignment once set, they will remain locked.
• The Z-Shim likewise will be adjusted during
  initial setup once the optical axes has been
  aligned, no further adjustments are needed at
  this point the Opt-Axis Adjust Rails are secured
  with bolts through the Z-Shims into the Interface
  Structure (Bolts not shown)
• The horizontal slots in the Foot Focus
  Adjustment are used for fine-tuning the focus
  direction of the HICIAO instrument.
• ONCE THE INITIAL SETUP IS COMPLETED, THE HICIAO
  INSTRUMENT CAN SIMPLY BE RETRACTED BEFORE AND
  AFTER INSTALLATION BY MEANS OF THE CRANK ON THE
  RIGHT.
• The Interlocking Pins require the Vacuum Jacket
  to be moved horizontally away from the
  Fore-Optics for the first inch or so.
• There is also a design feature to allow for
  precise, repeat positioning of the Vacuum Jacket
  w.r.t. Interface Structure. This is shown in the
  next slides.

27
Interlocking Pin Qty2 Press fitted to VJ Bottom
Plate
VJ Bottom Plate omitted
Hand Crank
Register Pin Qty2 Attached to VJ
Front End Stop Plate
28
Repositioning Hardware required on Vacuum Jacket
Register Pin bolted to VJ Bottom Plate
electrically insulated from VJ
Interlocking Pin
29

• INITIAL SETUP (with VJ sitting on Target
  Assemblies)
• Adjust Front End Stop Plate such that the
  optical beam coming from the AO is parallel to
  the optical axis of Cryostat. Front End Stop
  Plate has rotational adjustment around a vector
  perpendicular to the Nasmyth Floor.
• Adjust the Z-Shims to align the optical axis of
  the AO beam and Cryostat in the direction
  perpendicular to the Nasmyth Floor. ( Step 1 and
  Step 2 can be reversed)
• Move the Cryostat sidewise using the Side Adjust
  Brackets until the optical axis of the AO and the
  Cryostat coincide. Secure bolts that fasten the
  Opt-Axis Adjust Rails to the Instrument Frame.
• Fine tune any Focus errors by using the
  horizontal slots in the Foot Focus Adjustment.
• a) The Register Pins are bolted to the bottom of
  the VJ Bottom Plate (previous slide)
• Both the Register Pins and Front End Stop Plate
  have hardened surfaces where they match. The
  match on the near side is between the Register
  Pin and a V-Groove in the Front End Stop Plate,
  at the far side between the Register Pin and a
  rectangular slot (see next slide). This will
  insure accurate repeat positioning in x and y.
• c) Interlocking Pins and corresponding holes
  in the Fore-Optics Structure have enough
  clearance between them to never touch. The
  Interlocking Pins serve as a safety feature in
  that the cryostat cannot be moved in any other
  direction than horizontally away from the
  Fore-Optics Assembly for the first inch.

30
Arrangement assures repeat positioning of VJ on
Interface Structure
Rectangular Slot
V-Groove
Interlock Pin Qty2
31
HICIAO mounted to Instrument Structure
HICIAO will either use its own Target Assemblies
or use IRCS Target Assemblies. (no final decision
yet)
Target Assembly Qty4
32
CRYO-MECHANISMS

• HICIAO uses 4 CRYO-Mechanisms
• Common Path Filter Wheel (CPFW)
• Pupil Wheel (PW)
• Differential Path Filter Wheel (DPFW)
• Detector Focus Mechanism

Except for the Wheels, the CPFW, PW and DPFW are
identical in design
33
Common Path Filter Wheel
Front
Back
Dowels lineup unit perpendicular to Optics Bench
Mounting surface
For more Details See PDR Document 3.2.2.3.6
Cover shown partially transparent
34
Filter Wheel Case Holder
Mechanism Registration Brass Slides permits
parallel, limited translation along the optical
axis
Slotted Holes allow limited adjustment along the
optical axis
35
Filter Wheel Cover removed
Magnets in Wheel
Detent Spring
Detent
Cam Driver Assembly
Hall Sensor
Geneva Wheel 12 positions
Filter Cell
36
Filter Access Cover held in place with leaf
spring
PHYTRON CRYO-Motor
Hall Sensor
Gear Train Ratio 81
Bearing Mount
37
Detector Focus Mechanism

• Maximum Travel Range /- 8 mm
• Resolution 5 micron
• Drive System Linear Ball Bushings with Ball
  Screw Drive
• Encoding Hall Sensor Magnet

38
Detector and Detector Focus Stage
Resolution 5 micron Drive Linear Ball Slides
w/Ball Screw Drive
Front View
Back View
39
ASIC (Schematic only)
Hall Sensor Substrate
Hall Sensor Substrate
Cold Feed-Through with G-10 Disk thermal
insulation
Ball Screw Drive 1mm Pitch
THK Linear Ball Slides
Flex Connection
40
PHYTRON CRYO-Motor
G-10 Isolation Tabs Qty4
Ball-Screw Bracket