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Rolling ring drive

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This does not provide a positive drive like a ballscrew, as it relies on friction or traction for the drive. It has none of the safety, efficiency or back-driveable characteristics of the ballscrew. Why is it described in detail here? Surely a link to its own page is what should be done? Tiger99 (talk) 15:48, 24 September 2018 (UTC)[reply]

Applications probably inaccurate

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I am unaware of any normal automotive applications which would involve both a ballscrew and a rack and pinion. If the ballscrew was used to move the rack to provide power assistance, or even automatic driving, the system would not be unjammable if the ball screw driving motor jammed, and loss of steering would result, leading to an accident. Electric power steering usually has the driving motor on the steering column, coupled via a large gear and worm, which also generates concerns about jamming. I am thinking that this has been confused by "recirculating ball steering" where the old-fashioned worm and peg or worm and nut steering box has been replaced by a short ballscrew and nut, which like all other "box" type steering systems actually provides rotary movement to a lever, and there is no rack as such. I would like to see a specific example discussed here, to provide evidence that this particular example is valid, otherwise I will be wanting to remove it. There are many other real applications of ballscrews which could be added. Tiger99 (talk) 15:43, 24 September 2018 (UTC)[reply]

History section is short and inaccurate

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The History section mentions the "invention" of the ball screw being tied to a patent from 1929, while fails to bring up several "similar" mechanisms that would also classify as a ball-screw created much earlier (eg. 1874 patent https://patents.google.com/patent/US155862). It would be nice to at least mention that "similar devices" have been around since the 19th century. 2801:84:0:1012:1DD6:3F94:9019:A8E9 (talk) 15:37, 5 March 2018 (UTC)[reply]

Ball screws do not eliminate slop

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I have worked with a number of lathes and universal grinders with a ball screw 'lead screw' and they have always had slop, especially on older and heavily used machines. —The preceding unsigned comment was added by 216.143.98.153 (talkcontribs) 15:34, 4 December 2006 (UTC).[reply]

Ballscrews, like anything else where you have moving parts touching each other wears. Also ballscrews are manufactured in a variety of different classifications to suit the job they are being used for.. Just because they have a fair amount of slop on an older, heavily used machine doesn't mean that ballscrews with zero slop(ie. backlash) doesn't exist.. Yes it is entirely possible to have a zero backlash leadscrew and nut but the friction component of the two will far exceed that of a ballscrew and friction equals more heat and wear.. — Preceding unsigned comment added by Cwalker1960 (talkcontribs) 00:20, 20 November 2013 (UTC)[reply]

Oh yes they can eliminate slop! The use of anti-backlash ballnuts is very common. They are made in several ways. Firstly oversized balls, which rely on Hertzian elastic deformation of nut and screw threads to keep things tight, at the expense of high rolling friction and no adjustment. Secondly, a double nut, shimmed between each half at the factory to take up slop. Thirdly, a double nut, set up in situ by mounting each on opposite sides of the bracket driving the moving part. The nuts are bolted by circumferential slots, and by rotating one relative to the other the action of the screw allows infinite adjustment. These can be readjusted at any time. There may be other methods. I will leave it for a while, for others to assess what I wrote for accuracy, and maybe add something suitable to the article. Tiger99 (talk) 15:56, 24 September 2018 (UTC) Just realised that I probably wrote or re-wrote the Preloading section some time ago, and forgot to sign it. It looks like the words I would have used. Tiger99 (talk) 16:01, 24 September 2018 (UTC)[reply]

Not used in floppy and CD-ROM drives

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I've never seen a ballscrew used in the positioner of any computer drive. I've seen leadscrews, bands, rack and pinion, linear stepper, recirulating ball linear guides with voice coil positioner (in very old hard drives). I didn't delete it because this isn't proof, but I'm pretty sure.

I can also back up the comment above that ball screws don't eliminate slop. They are however typically used where backlash is unacceptable, because their much lower wear rates allow it to be adjusted out. An ordinary leadscrew needs much more frequent adjustment and will eventually jam up on less worn sections of the leadscrew. Adx (talk) 03:09, 26 September 2009 (UTC)[reply]

I removed the statement that ballscrews are often used in floppy disk drives and CD players. Their leadscrews often have semicircular threads that look like ballscrews but are actually designed to drive against a straight wire spring. Adx (talk) 07:37, 23 March 2010 (UTC)[reply]

ballscrews are more often used to move large masses at very precise tolerances. There are many instances where it just isn't practical to use a ballscrew. A leadscrew is very capable of being extremely accurate but when moving a large mass, friction dictates the amount of accuracy it can successfully substain on a repeated basis before wear overcomes it. — Preceding unsigned comment added by Cwalker1960 (talkcontribs) 00:31, 20 November 2013 (UTC)[reply]

Request for more info

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Could a graphic or animation be added that better shows the ball screw operation? It is beyond me how this thing works. How are the groves cut in the nut? — Preceding unsigned comment added by 192.146.101.71 (talk) 20:50, 15 November 2011 (UTC)[reply]

I agree entirely. I don't have the capability to do this, but maybe someone can take inspiration from the article on roller screws, which seems to be somewhat better written than this one? Ball screws are very common, even amateurs with 3D printers or small CNC machines use them, roller screws are reserved for serious industry, so I think there is much scope for expanding the article. Tiger99 (talk) 16:05, 24 September 2018 (UTC)[reply]

Move History to Lead screw

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The discussion of how precision screws are traditionally (and still sometimes) made belongs in the wiki page for Lead screw, not here, because such lapping applies to all precision screws, not just ball screws, and because these techniques for precision screw development were first done in the 18th and particularly in the 19th centuries, long before ball screws existed. The history given here should begin with established lead screws and talk about how and when balls were first added. Douglas W. Jones (talk) 03:34, 31 January 2012 (UTC)[reply]

The uncited speculation about early manufacturing of precision screws is really jarring. A screw is a triangle wrapped around a cylinder, and thread pitch is constant so it can be cut as a pantograph with a tool holder. The early difficulty with screws was the non-linear spiral tip, as apposed to the helix leadscrew. Precision leadscrews, and tool holders were supposedly developed out of necessity in the 19th century(Some time before receiving a tunnel boring contract in 1825) by Sir Marc Isambard Brunel, and Henry Maudslay, not a discovery of an averaging technique. I would argue that the article doesn't need a history section, as compared to the leadscrew article. Lemtil (talk) 21:27, 16 April 2023 (UTC)[reply]