Retrofitting a 1986 Maho MH400E

Thanks John,
Is this logic correct then...

If the gearbox is not in mesh, and no switch is closed then current position between LH and MID, -->turn CCW to the LH and CW to mid position.
else if
gearbox not in mesh, and LEFT_CENTER switch closed, then current position between MID and RH and RH, --> turn CCW to mid and CW to RH

Mark

I thing more appropriate and more simple logic is
1 if u need to go to the left then turn ccw
2 if u need to go to the right than turn cw
3 If u need to go to the middle and Left-Center is 1 then turn ccw else cw
John

www.flickr.com/photos/mahomh600p/
www.flickr.com/photos/mahomh600p/8293681086
Even if the motors overshoot just a little the gearbox has some ball locking mechanism.

Thanks again John, that is much clearer now.

I just took a look through those photos. What a great reference.
Mark

My friend has made great progress on the gearbox.comp and a gearbox simulator to test it...
Github Wiki

It is looking really good.

I have a question about the mechanical's of the gear change motors.


They are rated:
U=24v
I=0.8A
n=28 rpm
P2=6W.

I am "Assuming" that these motors are so wimpy that if I run them into a hard stop due to the having a direction sense reversed in the software, they should stall without an tooth decay on the plastic gears. Am I being unrealistically optimistic here?

I also have a question with regards to the matrix-KB pin:
matrix_kb.MAHO_Panel.col-1-in
does the column and row numbering start at 0 or 1?

Mark

RotarySMP wrote:
I am "Assuming" that these motors are so wimpy that if I run them into a hard stop due to the having a direction sense reversed in the software, they should stall without an tooth decay on the plastic gears. Am I being unrealistically optimistic here?

I own a gear motor that is rated a bit higher at 24V/2A that would beg to differ, the very first time it hit a hard stop it chewed the plastic gears, and it was powered by a cordless drill battery at 14.4V, but it had enough current to render it unusable. If they are driven by relays, i would not risk it. Using current limiters is advisable, or a power supply with 1A max with automatic current limiting. Laptop adapters are very nice for such things but they tend to be in the 3.62A or 4.5A or 6.7A variety, so to much for your needs.
Or get some buck voltage regulars with current limiting for 1 to 3$ a piece on fleebay and set the voltage to 20V on their outputs a limit current to 1A. Used plenty of those to limit the current to motor drives that had no current limiting.