Toroid Winder w/o cutting the wire. - Page 1
Forum section: electronics / projects

author: Oneminde
author_rank: Regular Contributor
timestamp: May 22, 2019, 09:19:34 pm
content: I am trying to figure out or access information on toroid winders which use continuous feed rather than loading a cartridge which has a finite amount of wire (length) it can hold. Surely there must be a version where this is not needed ?Does anyone have any sort of information that can help me ?

author: Gyro
author_rank: Super Contributor
timestamp: May 22, 2019, 09:48:27 pm
content: I don't think that's even possible.What do you do with the huge 'excess' loop of wire that would build up as you repeatedly threaded the wanted wire through the centre hole? How would you store all of it on the winding cartridge? You would need to run it the same number of turns in reverse to recover the excess wire and I doubt it would it still be serviceable for further use after all the additional flexing and friction involved.

author: Oneminde
author_rank: Regular Contributor
timestamp: May 22, 2019, 10:12:46 pm
content: I don't know yet, that is why I asked ..

author: MagicSmoker
author_rank: Super Contributor
timestamp: May 22, 2019, 10:36:00 pm
content: It is topologically impossible to wind a toroid from a spool of wire unless you unwind the entire spool first before sending it through the center hole for each turn.

author: JFJ
author_rank: Regular Contributor
timestamp: May 22, 2019, 10:46:48 pm
content: Googling "shuttleless toroidal core winder" finds results like this:https://patents.google.com/patent/US4288041A/en

author: digsys
author_rank: Unknown
timestamp: May 22, 2019, 11:18:27 pm
content: I contracted for a company that has been winding torroids for 40+ yrs, and had dozens of winders. They always wished for such a machine, but it was neverpossible, according to their machine suppliers. I've even had a look at the issues involved .. too hard. Don't know about this patent, looks damn complex.The complexity / maintenance of existing winders is bad enough. It's quite an interesting engineering feat. Especially if the core centre is small, or the amountof turns reduces it dramatically .. that's when the shlt hits the fan :-)

author: ali_asadzadeh
author_rank: Super Contributor
timestamp: May 23, 2019, 08:35:36 am
content: Cool machines, i always wanted to build a normal one

author: Rerouter
author_rank: Super Contributor
timestamp: May 23, 2019, 08:51:42 am
content: The large automated ones just spin up there spool with the amount required to complete the full wind, Topology is working against you. This does let it use a larger continuous feed, but in batches of length,There is no other way that you can wind a torroid and still be able to remove the torroid at the end...So to give a run down of what is out there- Insert new torroid in winder,- Winder gap is closed to form a solid ring- Winder spools up the required length and cuts at the correct length- Winder winds the toroid turns- Remove completed torroid from device with lead wires, ready for the next.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: May 23, 2019, 09:43:17 am
content: Why would you even need this? You know ahead of time how much you need to wind, so what benefit would there be of continuous feed?

author: Wimberleytech
author_rank: Super Contributor
timestamp: May 23, 2019, 11:34:24 am
content: Quote from: digsys on May 22, 2019, 11:18:27 pmNot all disclosures in patents really work. Something can be patented and be totally bogus.

author: free_electron
author_rank: Super Contributor
timestamp: May 23, 2019, 11:45:23 am
content: toroid winders uses an intermediate spool. the indermediate spool has a hinged opening latch.- open spool hinge- put hinge through toroid- close hinge.- spin wire onto spool- spin from spool to corehttps://i.pinimg.com/originals/50/b4/89/50b489ec00c7fb79213d250a6dd01e96.jpg

author: Oneminde
author_rank: Regular Contributor
timestamp: May 23, 2019, 12:16:17 pm
content: Quote from: mikeselectricstuff on May 23, 2019, 09:43:17 amThe idea was so that I could avoid the intermediate stage of winding a shuttle and make life easier. Found one patent on a shuttleless version that seem interesting. Function is similar to Ruff's GmbH Magazineless winding head with the goal of producing tightly packed toroids.https://patents.google.com/patent/US4127238

author: Cliff Matthews
author_rank: Unknown
timestamp: May 23, 2019, 01:13:08 pm
content: Pardon my nube-like ignorance, but why don't toroid mfg's make something like an intermediate product, split in half and supplied in matched pairs with some ferrous bonding slurry and catalyst? It would make shipping them a little easier too. Winding's could cover 350 degrees of the core perhaps with the aid of 4 plastic slip-on L-rings, but would that bring down efficiency too much to be a viable product?

author: Psi
author_rank: Super Contributor
timestamp: May 23, 2019, 01:29:00 pm
content: It is possible, you just have to use one of the extra spatial dimensions predicted by string theory.That will let you move wire from outside to inside the toroid without having to break it.Good Luck

author: digsys
author_rank: Unknown
timestamp: May 23, 2019, 01:38:17 pm
content: Quote from: Cliff MatthewsThey do ! They make ALL type torroids - split / layered / slotted / gapped etc etc and they ALL have totally different properties ! and uses.The science of how they work / material used / shape / winding patterns etc etc is VERY complex and few people understand completely.ANY interruption to the consistency of the donut has major side effects, which are not fixable.For themajorityof uses, the 1 piece donut is the most preferable. If there was ANY solution, it'd have been implemented long ago.

author: Ian.M
author_rank: Super Contributor
timestamp: May 23, 2019, 01:45:26 pm
content: Quote from: Cliff Matthews on May 23, 2019, 01:13:08 pmYou can get split toroid cores - they are frequently used for retrofitting common mode HF EMI suppression.However for split core transformers and inductors, a pot core is generally preferable. A pot core bobbin is cylindrical so is much easier to wind, and as the ferrite core nearly completely surrounds the bobbin (apart from the slots to bring out the winding ends, field leakage can be lower than a toroid, even if its gapped by grinding the center leg.

author: Cliff Matthews
author_rank: Unknown
timestamp: May 23, 2019, 02:00:02 pm
content: Thanks, I've seen these many times over the years, but didn't know the name. Have these been used in 60Hz power transformers?

author: Ian.M
author_rank: Super Contributor
timestamp: May 23, 2019, 02:58:28 pm
content: I don't think so. At 60Hz you don't need ferrite, as soft iron is good enough and soft iron sheet stacked laminations or wound tape cores are a lot cheaper and easier to work with.

author: David Hess
author_rank: Super Contributor
timestamp: May 24, 2019, 12:05:31 am
content: Quote from: Cliff Matthews on May 23, 2019, 01:13:08 pmThey do but the interface at the cut surfaces is critical and now the problem has been transferred to the bobbin which will occupy additional space in the winding window.It would be better to use some other core form.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: May 24, 2019, 02:34:30 am
content: In fact, there are bobbins and cores made specifically for this purpose:http://www.mycoiltech.com/et20-common-mode-choke-bobbin-four-slots-coil-bobbin_p915.htmlThis is snapped around a single-piece core (rectangular outline, round cross-section), and gear-driven to wind the wire onto it.The core being a single piece, it can be made out of high-mu ferrite; but what's better is, with no air gap whatsoever, it maintains that high mu after assembly. Up to 15k mu_r is achievable.Tim

author: coppice
author_rank: Super Contributor
timestamp: May 24, 2019, 02:40:54 am
content: Quote from: Cliff Matthews on May 23, 2019, 01:13:08 pmUse a simple toroid winder and you can cover 360 degrees of a cheaper, simpler and more predictable core.

author: Psi
author_rank: Super Contributor
timestamp: May 24, 2019, 02:55:01 am
content: Be careful when re-using those half toroids with the bobbin.A lot of them have a small air gap in the center ferrite column and it's not very obvious when looking at them.Ones with the air gap are intended for other uses and as far as i understand this makes them pretty much useless for power supply inductors?Can anyone confirm this?

author: T3sl4co1l
author_rank: Super Contributor
timestamp: May 24, 2019, 07:40:51 am
content: Gap is good for inductors (stores energy) and bad for transformers (transmits power) and CMCs (blocks transmission of power).The latter two are really the same thing, used in two situations. Transmission of powerto groundis bad for transformers; transmission of noisein seriesis bad for CMCs.Tim

author: HighVoltage
author_rank: Super Contributor
timestamp: May 24, 2019, 08:18:07 am
content: I just came back yesterday from the Coil Winding trade show in Berlin and looked at the latest toroidal winding machines, because we need one for manufacturing in Germany.https://www.coilwindingexpo.com/BERLINThe toroidal winding machines have not changed much over the years, just got more precise and faster. I actually asked a few manufacturers if may be a new technology if on the horizon but all answered that this technology works well and will probably stay for a long time.

author: ali_asadzadeh
author_rank: Super Contributor
timestamp: May 28, 2019, 05:16:56 am
content: Guys do we have good videos on how they works? I managed to find only the ones that are used for big torids! what about the smaller ones used in PC motherboard, they have the diameter of under 1.5cm

author: Psi
author_rank: Super Contributor
timestamp: May 28, 2019, 06:24:57 am
content: Quote from: ali_asadzadeh on May 28, 2019, 05:16:56 amI think they are the same, just smaller.Although, the tiny motherboard DCDC toroids usually only have like 5 turns.So they maybe done with hand machine, since china labour is cheapThinking about it some more, with thick wire and only a few turns there maybe other automated options for motherboard DCDC inductorsThe wire will hold its shape, so it could be pre-bent into a spiral by machine and then rotated onto the toroid core.

author: ali_asadzadeh
author_rank: Super Contributor
timestamp: May 28, 2019, 10:52:48 am
content: Thanks, I tough they might have use different method, since they are small, and most of them use multiple parallel thick wires!