LEGO TECHNIC : 13661


Technic / 13661	13660 \| 13662

Subject:	Re: Looking for a one-way motor drive mechanism that is foolproof.
Newsgroups:	lugnet.technic
Date:	Tue, 1 Feb 2005 11:49:19 GMT
Viewed:	2896 times

In lugnet.technic, Geoffrey Hyde wrote: > I want to drive a conveyor belt which will be feeding items from a hopper, > however, I want to make a small mechanism which will, if the motor is > switched on with it's output shaft spinning in the wrong direction, > automatically turn the spin around to the right direction through a > reversing gear arrangement. Off the top of my head I can think of two ways, neither completely compact. One is to use the sliding worm gear trick, and take the two outputs and connect them to the belt in such a way so that if output A is engaged it drives the belt forward, while if output B is engaged it... drives the belt forward. This has the downside if gearing down a lot, but it should work. You could also do this with a differential rachet splitter and a torque-limiting gear or two, but it would be bulkier. > I am hoping it can be as simple as a gear that > gets driven around another gear until it > starts going the right way. I'm not exactly clear on your idea here, but it presents a third way - central drive gear engages a second gear that can perform a half-orbit around the central gear. If the drive gear rotates CW, the second gear (with a little bit of shaft friction) on it's pivoting frame swings around CW with it until it hits a stop. With the frame blocked, the small gear acts as a idler between the drive gear and the output on the right. Similarly reversing the drive gear swings the idler gear around to the other side, where it hits a stop and acts as the idler gear on a 2nd drivetrain, which you can invert so it's output matches the first drive train. There may be more compact ways, but I'm not thinking of them at this point in the morning. Why do you need it? -- Brian Davis

Message has 2 Replies:

		Re: Looking for a one-way motor drive mechanism that is foolproof.
Well, I want to make sure that the drive mechanism doesn't accidentally try to start the wrong way, and try to either feed material into the hopper base, which is hard to clean out if I have to make it easily removable, or jam and stall the motor (...) (19 years ago, 1-Feb-05, to lugnet.technic)

		Re: Looking for a one-way motor drive mechanism that is foolproof.
(...) Here (URL) is one compact arrangement using the sliding worm gear that should do the trick. Just connect the output shafts with two 16t gears and I think they will work the way you want...or if one is still going backwards, use three 8t (one (...) (19 years ago, 1-Feb-05, to lugnet.technic)

Message is in Reply To:

		Looking for a one-way motor drive mechanism that is foolproof.
I want to drive a conveyor belt which will be feeding items from a hopper, however, I want to make a small mechanism which will, if the motor is switched on with it's output shaft spinning in the wrong direction, automatically turn the spin around (...) (19 years ago, 1-Feb-05, to lugnet.technic)

7 Messages in This Thread:

Entire Thread on One Page:: Nested: All | Brief | Compact | Dots
Linear: All | Brief | Compact
This Message and its Replies on One Page:: Nested: All | Brief | Compact | Dots
Linear: All | Brief | Compact

Custom Search