To LUGNET HomepageTo LUGNET News HomepageTo LUGNET Guide Homepage
 Help on Searching
 
Post new message to lugnet.technicOpen lugnet.technic in your NNTP NewsreaderTo LUGNET News Traffic PageSign In (Members)
 Technic / 6212
6211  |  6213
Subject: 
Combo pump/piston control
Newsgroups: 
lugnet.technic
Date: 
Sat, 1 Dec 2001 21:12:44 GMT
Viewed: 
621 times
  
I'm working on an RCX project where I wanted to control a piston and keep
the pneumatics pressurized with the same motor. I thought this would be easy
since the pump doesn't care which direction the motor is running, but
translating the motor's direction change into a throw of the pneumatic
switch turned out to be more challenging than I expected. Here's my
solution:

http://www.brickshelf.com/cgi-bin/gallery.cgi?f=8684

In the first picture you will see a yellow rubber band from the motor to a
pulley. This pulley drives the gearing to throw the pneumatic switch. Once
the switch is thrown the pulley slips. This seems like a hack to me, but
it's the only approach I could come up with.

In the second picture you see the back where a 16 tooth gear (actually a
clutch, which really isn't needed due to the pulley drive) drive a 40 tooth.
I had to play with this gear reduction to get the right amount of force
against the switch (which is stiff), but not so much that the thing busted
apart. You can't see it here, but the 40 tooth is attached to an armature
through one of its outer holes.

In the last picture (from the top) you can better see how the switch is
attached to the 40 tooth gear. After the switch is thrown up or down the 40
tooth gear halts, causing the pulley to slip.

I'm sure this problem has been solved many times, and would love to hear
comments and know how others have solved this, especially more compact
designs.

Thanks,

Simeon Fitch



Message has 1 Reply:
  Re: Combo pump/piston control
 
(...) Nice work, I think there are at least two other approaches to this problem. You can implement a rack that'll slide away once the lever motion is complete. You'll probably have to use two rubber bands to make sure the gear will "catch" the rack (...) (23 years ago, 2-Dec-01, to lugnet.technic)

3 Messages in This Thread:

Entire Thread on One Page:
Nested:  All | Brief | Compact | Dots
Linear:  All | Brief | Compact
    

Custom Search

©2005 LUGNET. All rights reserved. - hosted by steinbruch.info GbR