Relay Kit for Action Clock Motor

[newhobby]

I am looking for an electronic kit to control a 3v gear motor (such as a Tamiya #70103 or Velleman #KNS7) in a small action clock project that I want to build.
The kit is to have a relay that will turn motor on, which will cycle mechanical action till a micro switch is triggered, stopping/resetting the motor's cycle.
This will have to accurately trigger every 60 minutes.

As I am very much an electronics beginner, I would be grateful for some recommendations. Thanks!

 

[KMoffett]

Is this all battery powered, or do you have access to line power? How fast does the motor turn? What is the approximate time of one motor-on cycle?

Ken

 

[newhobby]

While I do not have the total design as yet, the DC gear motor that I intend to use will run on a couple of AA batteries. It will probably cycle for 15-20 secs. at about 2 RPM.
While this project is intended to be a clock, there will be a separate clock insert. The motor will drive some mechanical action on the hour, go through the cycle and reset for the next trigger (much like a cuckoo clock).

 

[KMoffett]

To maintain accuracy, over long periods (days...weeks...months), I think you're going to have to somehow link your motor control to the minute hand on the clock insert. A STOP switch, a trigger linked to the minute hand, monostable multivibrator with a time period long enough to move the motor past the STOP switch. The monostable will be tricky at <3V, because the motor will pull down the voltage of the AA batteries.

Ken

 

[KMoffett]

Something like this might work. According to the datasheet an LMC555 will work down to 1.5V

Ken

 

[Mr RB]

The "separate clock insert" will probably have a little quartz driver IC that makes a pulse exactly every second (or twice per second).

You could connect that to a binary counter IC set to count to 3600 (3600 seconds = 1 hour).

Then use a 555 timer to run your motor to do it's task.

 

[KMoffett]

The 1.5V battery clocks have an H-bridge type output to drive the motor coil. Two pulses at 2 second intervals, but 180 degrees out of phase. OR'ed, they make a great 1 pulse per second clock. But to get at the IC you have to tear the mechanics apart...and good luck getting it back together and working...I've tried. If you can, that's the way to go. Otherwise the minute-hand electromechanical sync (Microswitch, opto-interrupter, Hall effect...) to a monostable would be my choice.

But, that's just my approach.

Ken