Belt variator?

[John MCParticipant @johnmc39344]

[John MCParticipant @johnmc39344]

I've had this device stored away in my garage for along time. Seems to be a variable speed vee belt drive, expanding pulleys by the look of it.

I acquired it many years ago thinking it may make a variable speed drive for one of my machines, never got around to it. Not likely to now because VFD's make it much easier.

Anyone recognise the device? Anyone want it before I let the scrappy take it away?

John

[Martin ConnellyParticipant @martinconnelly55370]

Looks like something to hang under a table saw or a conveyor belt. As you say, such roles have now been superceded by VFDs which can be operated remotely and do not wear the same way this style of speed control will.

Martin C

[Nigel Graham 2Participant @nigelgraham2]

The Bridgeport turret-mills, and no doubt other makers', used something similar, I believe.

Yes – I'd be interested.

Size? Ratio range?

Depending a bit on ease of delivery / collection it might well suit the Denbigh horizontal mill I am slowly re-commissioning, but which would be fine with a normal 1ph motor. (My other machines have VFDs)

[Martin KyteParticipant @martinkyte99762]

Be a good drive for a potters wheel

regards Martin

[An OtherParticipant @another21905]

I have a wood-turning lathe which was originally fitted with a very similar system – I thought these photos were of the lathe to begin with!

It did work very well – for a time. One pulley was sprung to force the cheeks of the pulley together, and the other was connected to a lever which adjusted the relative spacing of the cheeks, so the drive belt was forced (e.g.) "up" the pulley cheeks, and pulled down into the other sprung pulley, thereby altering the drive ration.

The pulleys looked exactly like the ones in the photos, arranged so the pulley cheeks "interlock", but eventually the cast aluminium 'webs' failed, and the cheeks separated from the hubs – and I never was able to find a replacement. The lathe has 3-phase motor and VFD now.

[Dave HalfordParticipant @davehalford22513]

That's a bigun, I've got 2 side by side cones on my Rockwell Delta lathe for 1HP.

That might need matched belts all round and ordinary ones are £50 each

[NealebParticipant @nealeb]

The Smart and Brown 1024VSL (Variable Speed Lathe) uses a very similar drive with expanding pulleys that takes the drive from a 3HP motor.

I had a similar "broken pulley" event recently, but had been lucky enough to have bought a cabinet full of "stuff" with the lathe. Right at the back, brand new in bubble wrap, was a new pair of pulleys. I suspect that the reason that mine broke was that the motor-driven leadscrew arrangement that pressed against one of the pulleys was not quite centred, so putting an unfair load on the pulley. Eventually, it fatigued. I'm guessing, but I did take care to realign things when reassembling.

I did consider a new motor/VFD combination, but this was cheaper and, given the battleship build of the S&B, possible without a forklift to remove the old motor/variator assembly!

Edited By Nealeb on 04/01/2023 15:41:49

[DiodeDickParticipant @diodedick]

I was surprised that no one mentioned the Daf Variomatic transmission.

i have seen a similar continuously variable transmission used on coal feeders. They used chains and grooved pulleys, rather than fan belts. Wish that I could remember who made them…

Dick

[noel shelleyParticipant @noelshelley55608]

NO it's not a big one – The ones on a combine thrashing drum or the transport drive are about 18" in dia. Noel.

[Nick Clarke 3Participant @nickclarke3]

Posted by DiodeDick on 04/01/2023 16:09:41:

I was surprised that no one mentioned the Daf Variomatic transmission

Rayleigh mopeds with the Mobylette engine used a similar primary drive. A couple of guys in the Nottingham SMEE members built 5" IC shunters using them in the early 70s.

[Howard LewisParticipant @howardlewis46836]

Reminds me of the drive for 5 and 10 hp Hasrtidge fuel injection pump test machines.

Howard.

[old martParticipant @oldmart]

My Suzuki Burgman 400 has 34 hp driving a variator with a 25mm wide belt at up to 7000rpm. The pulleys are aluminium, and the belts should last 14500 miles.

[not done it yetParticipant @notdoneityet]

Hi John,

I’m dropping you a PM.

[JellyParticipant @jelly]

Hi John,

I have also dropped you a PM, although am clearly late to the party.

[John MCParticipant @johnmc39344]

OP here, thank you to everyone who replied to my query. It has now gone to a new home, sorry to disappoint everyone who expressed interest in taking the device off my hands.

John

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