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Complicated Diversions (Rotating Monitor, Yes or No)

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XyloSesame:


--- Quote from: ark_ader on October 17, 2007, 01:11:44 pm ---I tried rotation, but failed and nearly damaged the LCD.

--- End quote ---
Nearly damaged your LCD? That doesn't sound good... Mind telling us what happened so we can learn from what went wrong?

I'm moving the rest of my thoughts to my project announcement thread as they're getting more into design than general advice...

DaOld Man:

Ok, here is a drawing I promised of a simple DC motor controller.
Opto-isolator Q1 is turned on by the computers LPT port.
Q1 turns on small SPDT relay K1.
K1 N.O. contact closes, turning on CWR relay.
CWR directs current flow through motor to turn it Clockwise.
Motor turns clockwise until limit switch CWLS opens.
CWLS turns off CWR, which stops motor.
When computer signal turns off, Q1 turns off K1.
K1's N.C. contact turns on relay CCWR.
CCWR rotates motor counter clockwise by sending reverse current through motor.
Motor rotates until limit switch CCWLS opens.
CCWLS turns off CCWR, which turns off motor.
Computer output ON= turn screen clockwise.
Computer output OFF= turn screen counter clockwise.
Diodes D1 and D5 and Capacitors C1 and C2 are to keep relays from chattering if voltage drops when motor starts (this may not be necessary if you have a small motor.)
Diode D2,D3, and D4 are necessary to protect the circuit.
Brake Rx is a power resistor, used to brake the motor by sinking back generated current when CWR and CCWR are both off.
Mechanical stops will stop the motor if a limit fails. Stalled motor will blow fuse.
If computer control is not desired, Q1 can be replaced with a SPST switch.
Or K1 can be replaced with a SPDT switch.
Switch up, screen CW
Switch down, screen CCW
Notice also I show an LED in series with Q1. This would just show the status of the computer signal, and is not really necessary..
Brake Rx and fuse would have to be calculated on type of motor used.
CWR and CCWR are both 3PDT relays, current based on motor current.
All relay coils voltages are same as motor voltage.
Power supply is not shown, but is fed into bottom of circuit. (- and +)

Cornchip:

  I'm trying to follow along (I'm not electrically inclined).  Q1 is the input that can be replaced with a SPST switch. Is the switch held for the duration of the movement or is it pressed once until CWLS or CCWLS are reached? (making this a single button push or single button hold?). Nice work....this is something I will definitely try for myself.

 Cornchip.

DaOld Man:

The switch would have to be maintained, or held.
Turn the switch on, it rotates. The switch stays on.
Turn the switch off, it rotates other direction. switch stays off.
A simple on/off switch can be used to replace Q1.
A SPDT (single pole, double throw) switch would have to be used to replace K1.
A toggle switch would do just fine.
here is a diagram showing the switch replacing Q1:


DaOld Man:

And here is the circuit with K1 replaced with a SPDT maintained switch.

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