Can it be done? 12v automatic door lock used as linear actuator.....

Projects General Guidance
1

UPDATE TO ANYONE READING! THE DOOR LOCK IS A 12 VOLTNOT 24 VOLT****

Hi!

I have a curious question.

Please keep in mind I am neither and electrician or engineer. Just a hobbyist.

My project requires that I produce and up and down linear motion that has about an inch and a half of travel.

Kind of like a whack a mole, but tiny. It goes up and then it goes down. This motion does not seem simple or cheap to produce. Linear actuators are crazy expensive and terribly noisy. Then I remembered that a door lock in my dads Cadillac kind of worked in this way. So I checked amazon and there door lock actuators are like 4 dollars a pop. Really in my price range and does exactly what I need it to do.

Can I power this and program it through the arduino without frying it?

I popped one open and it looks like a standard DC motor in there. Could it be possible just to connect the motor as I would any DC motor from my kit?

Thanks ahead for any advice.

2

Without seeing the exact motor and its specs, all I can offer is general info.

Find out the stall current of the motor and look for an H bridge rated to take that current. The H bridge can be controlled by the Arduino. The motor will need an external power supply rated for the motor (stall) current. If the stall current spec can't be found, measure the winding resistance. Divide the motor power voltage by the winding resistance to get an estimated stall current.

Some DC brushed motor H bridges.

3

The motor is the same as the one in the attachment or in this link:

Thanks again!

power-lock-actuator2.jpg

4

Hi,

DISCLAIMER: Mentioned stuff from my own shop...

You can also do,this with a simple off-the-shelf relay board like THIS:

Two relays can be used to run a DC motor in either direction (Sorry for this schematic!)

Arduino can run such a relay board easily.

--BETTER DIAGRAM! --

5

Thanks for the quick updated diagram!

Question....

Would I need the board with:

SRD-05VDC****

or

SRD-24VDC***

The output I gather would be 24V to the motor?

Setup is USB input to arduino power so it would be 5V...

6

Are you sure about the 24V? Most automotive components are 12V.

7

I was not sure....I checked again!

It is 12 volt.

Sorry all! 12 volt!

8

You would use the SRD-05VDC. the 5VD refers to the voltage used to operate the relay. The relay itself will be able to switch both AC and DC supplies at a range of voltages. In your case you would be switching 12V DC going to the motor.

The relays use current. According to the datasheets you could power two of these relays from the Arduino. however if you plan to connect other things you should calculate the total used.

9

stobi77:
My project requires that I produce and up and down linear motion that has about an inch and a half of travel.

Before you start ordering parts and building, verify that the actuator has the travel you need. These have a travel of just about 1" and a stall current right around four amps.