Attaching a head to a DC motor

**super-fly** · 01-21-2007, 04:45 PM

I want to attach a servo head(one of those X shaped ones or a large circular one) to a dc motor with a high torque gearhead. I want to transfer the rotary motion of the motor to linear motion to drop a shelf about 2 inches. I didnt really want to use a serve because I just want to put it on a three way switch to lower and raise it when I want. Any ideas as to how I would securely attach one of these heads. Also do dc motors with gearheads have holding torque with no power going to them?

Thanks

**Volsfan** · 01-21-2007, 05:11 PM

http://www.servocity.com/html/3-12v_gear_motors.html

Check that out, and the gearhead should hold just fine

**super-fly** · 01-21-2007, 07:30 PM

Cool...thanks. I just want to make sure that it will hold, I'd rather not have to use any sort of latch or anything...it will be holding about 3 pounds.

**canadiandream** · 01-21-2007, 10:59 PM

No, not on their own - they do not hold torque. Sometimes the friction in the gears, or the direction resists motion but they are not like a servo.

Originally Posted by super-fly

Also do dc motors with gearheads have holding torque with no power going to them?

Thanks

**super-fly** · 01-21-2007, 11:09 PM

hmmm...do i have a better option. Linear actuators are too much. I was thinking a power door lock actuator, but i think it would move too fast and it would not give me enough linear motion either. I don't think I can use a power antenna motor cause i dont have a ton of space. I wanted to stay away from a servo cause then i have to get a controller for it and everything. I was trying to stay simple.

**Volsfan** · 01-22-2007, 04:01 AM

I guess it would depend on what gear ratio it is. Mine are 12vdc, 4 rpm's and hold just about anything I can attach. The bracket would break before the motor reverse