Motors, bearings

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Motors, bearings Sensors

• By Peter Lau

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(No Transcript)
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Motor A
Motor C
Disc 1
Disc 2
Motor B
Dummy Disc
Disc 3
Disc 5
Disc 5
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Reflective photo sensors
Motor A
Binary encoder
Finger
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To verify whether the lead is in the bayonet gear
or not
Motor A
To identify which lead is at The center of the
beam
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Encoder Reader
Bayonet Gear Turn 15 to clockwise to unlock
and anti- Clockwise to lock
Motor B to drive to turn the disc holder 15
clockwise anti-clockwise
Encoder
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Motor C
This bayonet gear is to drive the diffuser
catcher forward and backward
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Already, it is showing insufficient space on the
Base plate to mount all our motors and driving
mechanism.
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Air Motors

• Must be non- magnetic
• Acetal Body, SS shaft, Ceramic bearing.
• The company does it is Dynatork
• 10 to 12 weeks deliver time
• The cost is around 1,000 excludes VAT for 3 off
• Working pressure 100 PSI
• The maximum torque is 2.8 Nm
• The speed is 200 rpm
• No speed control
• No positioning control
• What problem we will tackle due to above
  parameter?
• How to stop it?
• Any accuracy concerns?

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For the Carousel

• The total mass is about 70 kg
• The moment of inertia is about 5.1 kg m²
• To stop the carousel-
• To reduce the speed by introducing the gear box A
  with gear ratio 2001, driving teeth ratio 31,
  total reduction is 6001
• By use of the binary sensor to read the position
  of carousel.
• By using the spring ball and dimple to guide the
  stop position of the carousel.
• Use the lock pin to hold the carousel in place
  before the next motion

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This encoder can be a stick type or just Painting
on the top .
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For the 15 disc holder

• Drive by the air motor B
• To reduce the speed by introducing the gear box B
  with gear ratio 511, teeth driving ratio 7.77
  1, total reduction is 4001
• By use of the Heidenhein 4000 series encoder to
  ensure the very high accuracy of positioning.

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For the diffuser plate transportation

• To locate the lead disc
• To reduce the speed by introducing the gear box C
  with gear ratio 31 and the teeth driving ratio
  of 2.71, total reduction is 8.11
• Use RS- micro switch to detect the position of
  the lead disc at the bottom position.
• Use RS reflective photo sensor to detect the top
  position of the lead disc.

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The Bearings

• The bearings are all in stainless steel type from
  Kaydon
• Totally 11 bearings are required.
• The cost of bearing will be about 3,400 plus VAT
  (estimation only)
• The delivery of some of the bearing may be long
  according to the feedback from the sales
  representative. Initial statement from him for
  the delivery time is October. And he is still
  bargaining with the factory.

The Sensors

• 2 micro switch, 5 reflective type photo diode, 1
  reflective type photo sensor 2 encoder
• The cost of sensors have not quoted yet.

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Summary

• The detail design is not yet finished. Details
  needed to be drawn later.
• Changes to the mounting supports for the motors
  and the locking mechanism may need to be revised
  to fit into the existing base plate, the size of
  which is fixed
• The sourcing activities of the sensors has not
  started yet.
• The control interface such as valves, fittings,
  counters and CPU need to be added
• The gearbox design is under process by J. Tacon.