Magnetic clutch

I was looking at ways to make a simple clutch for the main drive on my Warco 600.

A person on another forum asked a similar question and was advised to use an automobile magnetic air con compressor clutch.

That person used car aircon clutches on his yacht winches.

I was given a defunct one to look at and it was very compact (all in the pulley) it would have to be 12v powered but the sudden engagement might be detrimental to the drive train.

Air gaps are very critical for operation but wondered if friction material could be placed either a full disc or segments like some bike clutches between the metal contact faces.

This clutch unit would be fitted to the main drive motor I don’t like stopping the motor for checking dimensions and cost wise the clutch would not be too dear to modify.

It might have to be a commercial vehicle one to cope with the motors power?

Making a cone clutch like Anthony Mounts would be an alterative but time is valuable, as I prefer to make models etc.

Is the magnetic clutch feasible or are there too many problems.

Paul

Edited By Windy on 11/04/2013 16:56:23

Edited By Windy on 11/04/2013 17:01:09

hi i fitted a magnetic clutch to my champion mill and it works well it was made from a 12v clutch from ebay and a window motor from the scrap yard cost less then £50.00 i will take some photos on friday and post them                                                                                                                         

Edited By Kevin Bennett on 11/04/2013 17:33:00

My understanding is that car aircon systems theoretically need 5 to 10 HP to drive them. Obviously the wide range of engine speeds makes any calculations a lot more complex than for a simple constant speed drive but obviously the clutch has to cope however fast the engine is turning. At normal 1420 rpm electric motor speeds 2 hp or so is probably well within specifications. In practice folks like us tend not to use anything like full power of the motor so you should be fine.

The belt drive will damp out any shocks due to fast engagement. I believe some systems have a short period of slip whilst things come up to speed designed into the control gubbins.

I have successfully used the simple jockey pulley slack/tight belt clutch on several occasions. OK up to around 1 1/2 to 2 HP. Automotive spring loaded tensioning pulleys for serpentine belt drives are a useful source of components.

Clive

In MEW 159 Ken Wilson describes an electrically operated clutch fited to a Harrison M300, should be adapatable to pretty much any machine with similar primary drive arrangements

Graeme

Don't forget many electric motors also have a brake unit on the rear which can be canibised.

Motors can be had quite cheaply at local scrap yards.

Thanks Graeme that is just what I need there are so many useful articles in MEW.

Paul

photos as promised this is a 12v clutch and a 12v motor from a car window runs from a small transformer as i wanted it to be low voltage and safe.

it was easy to fit but a few months to get all the bits from eBay and the scrap yard, i have the motor running all the time and just switch it on and off as i want it and it works very well.

Ty Kevin

Edited By Kevin Bennett on 12/04/2013 08:44:47

Hi Kevin interesting photos did you buy the speed controller or make it.

Could you send me details of it please and the transformer.

As a bit of a skip rat I am always trying to recycle what others throw away problem now when the local council used to let you rumage at the tip that's out of bounds today.

Paul

hi Paul i was very lucky as it was a skip find from an in industrial retail park all the wires was cut off and was easy to re-connect , the transformer is a laptop type and was 12v not 18v as most laptops are now lots on eBay and cheep. the bed drive fixing is a rubber spider coupling this takes up the snapping of the clutch when switched as for the motor running all the time this lets you still use the hand wheel manually.

i will see if i can take a video on my camera i have never done this before so may take a while

thanks Kevin

Graeme

You mean this one

Ken,

That's the one

I've just obtained a car aircon compressor complete with clutch brand new for very few beer tokens.

I've spent the afternoon dismantling it and removing what appears to be useful, some very high quality thrust and needle roller bearings amongst other bits.

I will post some pics later of the 'salvage' and clutch unit.

Now need to apply a little grey matter to how I am going to mate this to the lathe

Graeme

hi i had no luck with the video my camera is crap but you will find the low voltage is the best option and works fine for me, if you need any more photos on my instal message me

ty Kevin

Can't remember when it was, but I seem to remember something about using an air con clutch in ME. Ian S C

Peugot 504s vintage 1980 used a radiator fan that was actuated by 12V. As radiator fans consume .5 ->5 Hp, it should be good enough for medium sized lathe. The set up was like a thick pulley with the fan belt running on the outside. On application of 12v to the stationary brush, the centre portion would lock up to the outer.

Frank

Frank,

You've brought back traumatic memories of Ford thermo-viscous fans, VV carbs and automatic chokes...

Neil