Hi Guys

Can anyone help me out, first off it’s not model engineering but never the less it is engineering.

I’m trying to fix an air compressor on my car, the compressor will work but the clutch has become unbolted from the splined shaft on which it slides.

I’ve watched a few videos on youtube explaining how the air compressor works, basically there is a field coil over which the compressor pulley fits, this pulley is constantly rotating driven from a belt via the crankshaft ie when the engine is running the pulley is turning.

The end of the shaft this pulley fits on is splined onto which the compressor clutch fits.

The clutch does not contact the rotating pulley unless the air con is switched on from inside the car.

Once switched on the field coil sets up an electro magnetic field which pulls the compressor clutch along the splines against the rotating pulley this then causes the compressor shaft to rotate and pump the refrigerant around the system.

From the videos I’ve seen there is a spacer fitted inside the clutch to give it an air gap between it and the rotating pulley when the air con is switched off.

Two things, one I can’t see a spacer and two the bolt or screw is no longer there maybe both have fallen out when the clutch came off, I guess I’m lucky I did not lose the clutch also.

OK back to what I don’t understand, if I screw the clutch onto the shaft it locks the whole thing up against the rotating pulley meaning the compressor never turns off.

Does anyone have any idea on how the clutch is bolted onto the shaft without locking it permanently against the rotating pulley but at the same time allowing it to slide along the splines to contact the rotating pulley once the field coil is energised.

I may be totally wrong here, the shaft has a blind tapped hole in it, surely the bolt which holds the clutch in position doesn’t have to bottom in the hole and that’s what stops the screw coming lose??

Can anyone also tell me how to upload some photos on this site?

Thanks to anyone who can shed some light

Clive

Hello Clive Forster

Thank you for taking the time to reply and the link, I will try and do a sketch of what my setup is like and try to post it on the forum.

More than likely it will be Monday 25th before I can get to it.

Thanks again

Clive