View Single Post
  #3   Spotlight this post!  
Unread 30-11-2014, 20:01
asid61's Avatar
asid61 asid61 is offline
Registered User
AKA: Anand Rajamani
FRC #0115 (MVRT)
Team Role: Mechanical
 
Join Date: Jan 2014
Rookie Year: 2013
Location: Cupertino, CA
Posts: 2,224
asid61 has a reputation beyond reputeasid61 has a reputation beyond reputeasid61 has a reputation beyond reputeasid61 has a reputation beyond reputeasid61 has a reputation beyond reputeasid61 has a reputation beyond reputeasid61 has a reputation beyond reputeasid61 has a reputation beyond reputeasid61 has a reputation beyond reputeasid61 has a reputation beyond reputeasid61 has a reputation beyond repute
Re: pic: Cim with Encoder CUI Inc. AMT 102-V3524

Quote:
Originally Posted by Richard Wallace View Post
Sorry I misunderstood your idea earlier.

So, if I am getting it correctly now, you would put a third bearing on the motor shaft, between the encoder and the pinion? Maybe a 608, with 8mm ID x 22mm OD x 7mm length. Then you'll have 31 - 9 - 7 = 15 mm left for the pinion and its retainer, so a standard 19 mm pinion would need to be cut down to about 12 mm. This will still be enough to engage a 3/8 inch (9.5 mm) gear tooth face. A little more demanding of axial gear alignment, with very tight axial clearances.

Edit: maybe leave about half of the 608's axial length protruding from the encoder adapter so it functions as a pilot for the gearbox? This would allow larger pinions (e.g., 14 tooth) to clear the pilot diameter, making gearbox assembly easier, while relieving some of the tight axial clearance problem.
Am I wrong in saying that the axial tolerances can be a little looser, as the whole cim/encoder assmbly is mounted by two screws with no boss? I'm not sure if that would work, but wouldn't the cim shaft be aligning this anyway?

I would actually use an 8mm ID x 16mm OD 5mm long bearing. On a 3/16" thick plate, it only sticks out about a hundreth of an inch. It has a pretty high load rating too.
Reply With Quote