Working with small motors

[burnt]

nice tombstone prop

Stepper motors are a far better option for moving displays like this... not only do they have tons more torque at lower rpm but their positioning and speed is (of course) absolute and infinitely variable. Plenty of cheap drivers out there now and there's even some p&p dmx stepper controllers available which makes it a breeze. And lots of off the shelf hardware, nema23's generally have a 1/4" shaft which accept a huge range of couplings

And they never wear out!

i was playing around with a stepper motor from old scanner today. was able to run from arduino but with no torque, also tried stepper motor driver DRV8825 but no movement....

 

[caretaker]

I'm not sure if they ship down under but check out http://www.monsterguts.com/store/home.php

 

[djgra79]

OK brains trust - riddle me this: Just bought a wiper motor (2010 Toyota Kluger for those playing along at home) and the plug on it has 5 pins:
View media item 240
I popped this off to see if there was a simple pos/neg, and there looks to be near the motor itself:
View media item 241
But I'm wondering if I'm able to hook wires up directly to these, and what purpose the plug cap has, particularly as it seems to have some type of gear wheel stopper thingy in it. I'd like this motor to turn 360 and not stop (like many rear wiper motors do) but want to check - can I make do without this plug and go direct?

 

[Kitman]

Found this video on you tube which explains the wiper motors and what the wires do
View: https://www.youtube.com/watch?v=1Ww5-pmiokc

It was made by someone who uses the motors for halloween props worth a look.

 

[djgra79]

Thanks Kitman. Never thought to look at youtube (rookie mistake)
So I wonder if I was to reverse the pos/neg polarity, would that simply make the motor run backwards or go bang?!

 

[David_AVD]

Reversing the polarity will reverse the direction.

 

[algerdes]

I believe that most wiper motors go in one direction only. This simplifies the wiring and the mechanical. The linkage from the circular motion first pulls the wiper arm, then pushes it on the second half of the rotation. The "park position" is set so the wiper is in its "home" position when it becomes disengaged.

 

[algerdes]

I believe that most wiper motors go in one direction only. This simplifies the wiring and the mechanical. The linkage from the circular motion first pulls the wiper arm, then pushes it on the second half of the rotation. The "park position" is set so the wiper is in its "home" position when it becomes disengaged.

You must have been typing when I was.
As far as the wiper going in reverse, this is a new one on me. I'll have to get one and test this.

 

[algerdes]

I found my notes from "shop class". This video,
View: https://www.youtube.com/watch?v=a7qJy8mYi6s
, at about the 12 min 45 sec mark explains why we were taught not to reverse the polarity. Technically it can be done, but functionally you may want to reconsider.

 

[djgra79]

Thanks guys. I'm not fussed if it does go backwards, my main concern is that it has continual 360deg rotation, no stopping at anytime when power is applied. I'll still need this cover to protect the gears, but I'll have to just poke around and find the pos & neg wires and just use those.
Hopefully when I get home and clean it up a bit the pos & neg terminals are labelled on the motor.

 

[David_AVD]

You should be able to use the continuity function on your multimeter to trace which 2 wires on the 5 pin connector go to the 2 tabs you mentioned earlier.

 

[djgra79]

Yeah that's what I thought. Just need to try and determine which of those 2 pins is pos/neg.

 

[David_AVD]

I wouldn't worry about it to be honest. The type of parking contact in yours look unlikely to be affected by reverse rotation.

 

[djgra79]

I'll post an update this evening upon further investigation

 

[the grinch]

Hey dj im possibly a bit late with info here and haven't looked at any of the videos posted but being a car person all my life I know the top you have pulled of is basically the stop exactly in same position mechanism . From experience with earlier model wiper motors earth the body and add power to whichever pin gives you the required speed . And yes motor will spin in same direction constantly as I feel some people think wiper motors change direction left too right for wiper action not true . They constantly spin in same direction .