Let's Make Robots!

remove brake from wheelchair motor

I bought a couple of FRAMCO wheelchair motors, apparantly originally produced from Hastings England. Anyway, on the connector there are 4 connections. Red, Black and 2 brown. I am not sure of the sequence to hook these things up, so I tried a few different combinations and did get it to work yesterday. Today I can't seem to get it to work. What adds to the situation, I took off the cover and cut the wires going to what appears to be an electric brake. Then I put 12V on the black and red connection and I get a spark but the motor does not turn. I did take the end that have the brushes off also and replaced it and rebolted everything in the same position, but would like to know if anyone has had experience with these motors. Thank you, Jerry

Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.

I do have experience in modifying wheelchairs.  And the control circuitry and components by design will lock the chair if the power fails, or if the control circuitry seems glitchy etc.   These are all standard safety precautions in electric wheel chairs.  When the power goes out, you don't want grandma zipping down the hill backwards at 100 mph.

On mine, there were electric brakes which were designed to stop the wheels when 24V was not applied.  The control circuitry would send 24 volts to the brakes releasing them only when conditions were "just right", ie. when the joystick was sending the correct frequency of pulses.

I ended up just removing them - they are where on the base of my motors.

Ah, interesting. So cutting the brake wires causes them to be activated. Makes sense!

People usually want to keep Grandma alive ;)

I have a motor from an electric mobility scooter with an attached brake. The brake is controlled separately from the motor on my unit. It shouldn't be interfering with the motor unless something is causing it to trigger. On my motor, the brake is bolted to the end of the motor, on the opposite side from the axle. I suspect the axle extends a bit on the brake side, and the brake is attached to the axle this way.

If you've cut the wires to the brake, I doubt it is your problem. Is it possible that your batteries have run down? That would explain the behavior you are seeing.

It seems like the brake wires are somehow connected to the Black and Red wires to the motor somewhere around the motor brushes. By cutting them, is it possible that it interrupts the current flow through the motor? I am wondering if I should put a jumper wire on the ends that I cut. My battery has plenty of power because I checked it with a 12V battery operated winch and it runs the winch ok.

A picture is worth 1000+ words