Printed circuit motor. - UK Vintage Radio Repair and Restoration Discussion Forum

Tractorfan · 10th Feb 2017, 10:23 pm

Hi,
I've had this curiosity kicking around since the seventies and during four house moves. I think it's a printed circuit rotor from a DC 'flat motor'. I seem to remember that it had a hefty ferrite magnet on one side and the brushes ran on the inner part of the 'print' near the hole.
I wondered what became of these types of motor. Are they still used much?
Cheers, Pete.

Lloyd 1985 · 10th Feb 2017, 10:48 pm

Hi,
The motor in my Technics SL-5 direct drive turntable looks to be printed on a pcb. I'll try and find a photo of it...

Regards,
Lloyd

Radio Wrangler · 10th Feb 2017, 11:25 pm

From that period most likely Printed Motors ltd. They wound up as low inertia high torque servomotors

More recently there was a firm called Lynch doing them, trying for the electric vehicle/bike market.

David

Ed_Dinning · 11th Feb 2017, 8:43 am

Hi Gents , Cedric Lynch has been producing these since the 70s for a variety of applications and up to about 100A continious ratings. As magnets have improved, so have his motors.

Ed

M0FYA Andy · 11th Feb 2017, 10:41 am

That brings back memories! I had to control one of those as part of my MSc project back in 1974. It drove a model, about 5 feet long, of a gantry crane designed to unload iron ore from a ship's hold and drop it into railway wagons on the quayside. The requirement was to automate what could be done manually by a skilled crane operator, the trick being to damp out the sideways swing of the grab as it dropped into the ship or wagon, and do the job as quickly as possible. (The full-size crane was somewhere in Ed's neck of the woods, he might know where?). My part of the project involved designing and building the amplifier to drive the motor, and writing a program using Basic with embedded assembler code running in a PDP-11 to schedule the drive to the motor.

Happy days!

Andy

Refugee · 11th Feb 2017, 11:05 am

I have seen them in fax machines.

Malcolm G6ANZ · 11th Feb 2017, 12:36 pm

yes they are still in use. They have very high torque at low RPM and very controllable. They are used for gantry rotation on medical linear accelerators. The gantry is the rotating part of the machine and weighs in the order of half a ton. The control system and this type of motor allows very slow and accurate rotation.
https://encrypted-tbn3.gstatic.com/i...AxbITpA3A0wwte

The motors, two in this case, are at the bottom underneath the green items just to the right of the dividing screen. The green items are gearboxes.

Ed_Dinning · 12th Feb 2017, 8:04 am

Hi Andy, if it was iron ore it would probably be on Teesside, but I guess unfortunately scrapped by now (Unless Lucien has saved it!)

Ed

bikerhifinut · 12th Feb 2017, 12:44 pm

As far as I am aware the unloading gantries at Redcar ore terminal (River Tees) are still there, they hadn't been dismantled when I moved.
A.

10th Feb 2017, 10:23 pm	#1
Tractorfan Dekatron Join Date: Mar 2008 Location: St. Frajou, l'Isle en Dodon, Haute Garonne, France.(Previously: Ellesmere Port, Cheshire, UK.) Posts: 3,184	Printed circuit motor. Hi, I've had this curiosity kicking around since the seventies and during four house moves. I think it's a printed circuit rotor from a DC 'flat motor'. I seem to remember that it had a hefty ferrite magnet on one side and the brushes ran on the inner part of the 'print' near the hole. I wondered what became of these types of motor. Are they still used much? Cheers, Pete. Attached Thumbnails __________________ "Hello?, Yes, I'm on the train, I might lose the signal soon as we're just going into a tunn..."

10th Feb 2017, 10:48 pm	#2
Lloyd 1985 Nonode Join Date: Jun 2008 Location: Coningsby, Lincolnshire, UK. Posts: 2,820	Re: Printed circuit motor. Hi, The motor in my Technics SL-5 direct drive turntable looks to be printed on a pcb. I'll try and find a photo of it... Regards, Lloyd

10th Feb 2017, 11:25 pm	#3
Radio Wrangler Moderator Join Date: Mar 2012 Location: Fife, Scotland, UK. Posts: 22,902	Re: Printed circuit motor. From that period most likely Printed Motors ltd. They wound up as low inertia high torque servomotors More recently there was a firm called Lynch doing them, trying for the electric vehicle/bike market. David __________________ Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done

11th Feb 2017, 8:43 am	#4
Ed_Dinning Dekatron Join Date: Jan 2004 Location: Newcastle upon Tyne, Tyne & Wear, UK. Posts: 8,195	Re: Printed circuit motor. Hi Gents , Cedric Lynch has been producing these since the 70s for a variety of applications and up to about 100A continious ratings. As magnets have improved, so have his motors. Ed

11th Feb 2017, 10:41 am	#5
M0FYA Andy Nonode Join Date: May 2007 Location: Preston, Lancashire, UK. Posts: 2,511	Re: Printed circuit motor. That brings back memories! I had to control one of those as part of my MSc project back in 1974. It drove a model, about 5 feet long, of a gantry crane designed to unload iron ore from a ship's hold and drop it into railway wagons on the quayside. The requirement was to automate what could be done manually by a skilled crane operator, the trick being to damp out the sideways swing of the grab as it dropped into the ship or wagon, and do the job as quickly as possible. (The full-size crane was somewhere in Ed's neck of the woods, he might know where?). My part of the project involved designing and building the amplifier to drive the motor, and writing a program using Basic with embedded assembler code running in a PDP-11 to schedule the drive to the motor. Happy days! Andy

11th Feb 2017, 11:05 am	#6
Refugee Dekatron Join Date: Apr 2012 Location: Worksop, Nottinghamshire, UK. Posts: 5,554	Re: Printed circuit motor. I have seen them in fax machines.

11th Feb 2017, 12:36 pm	#7
Malcolm G6ANZ Octode Join Date: Feb 2006 Location: Bristol, UK. Posts: 1,042	Re: Printed circuit motor. yes they are still in use. They have very high torque at low RPM and very controllable. They are used for gantry rotation on medical linear accelerators. The gantry is the rotating part of the machine and weighs in the order of half a ton. The control system and this type of motor allows very slow and accurate rotation. https://encrypted-tbn3.gstatic.com/i...AxbITpA3A0wwte The motors, two in this case, are at the bottom underneath the green items just to the right of the dividing screen. The green items are gearboxes. Last edited by Malcolm G6ANZ; 11th Feb 2017 at 12:40 pm. Reason: modified link

12th Feb 2017, 8:04 am	#8
Ed_Dinning Dekatron Join Date: Jan 2004 Location: Newcastle upon Tyne, Tyne & Wear, UK. Posts: 8,195	Re: Printed circuit motor. Hi Andy, if it was iron ore it would probably be on Teesside, but I guess unfortunately scrapped by now (Unless Lucien has saved it!) Ed

12th Feb 2017, 12:44 pm	#9
bikerhifinut Octode Join Date: Nov 2013 Location: Penrith, Cumbria, UK Posts: 1,993	Re: Printed circuit motor. As far as I am aware the unloading gantries at Redcar ore terminal (River Tees) are still there, they hadn't been dismantled when I moved. A.