Paul Sherriff | 31/07/2021 18:02:10 |
12 forum posts | I wondered if someone could point me at the edition of the ME that contained drawings and build details of the Greenly reverser as used on the RH&DR locomotives A clever device formed of a stew reverser with a pole that unclapsed the nut and allowed pole reversing, giving you the choice of either method of reversing Thanks in anticipation Regards Paul |
Nigel Graham 2 | 31/07/2021 21:47:37 |
3293 forum posts 112 photos | A suggestion if your enquiry draws a blank. Essentially, design and make a half-nut held on a die-block working in a slot in the reversing-lever, to accomodate the vertical displacement due to the lever's arc. The nut would be operated from the trigger that would otherwise operate the quadrant catch; the thread itself giving the notches on a "quadrant" of infinite radius. (c.f. the toothed rack) Provided the engagement is sufficiently positive, you should need only the upper half of the nut, otherwise you are looking at a clasp-nut worked by a cam or double-ended lever, similar to that on a lathe. The thread would probably have to be of square form to remove any ramp-climbing tendency, and the lever preferably double-sided over the screw to support the die-block from both sides. Have you tried contacting the RH&DR for information? ' I believe there was an early 19C standard-gauge design for such a combined control, but which overcame the arc displacement problem by using a barrel-shaped screw. I think it was found too difficult to make economically; but I imagine it would have required either a thread-milling capacity very advanced for its time, or much simpler and much more likely, a centre-lathe fitted with a profile-follower. I do not know how it handled the question of thread-flanks not radial to the reverser-lever fulcrum / screw-radius centre. A profiled thread perhaps; the half-nut or catch made to swing about its own centre, or the nut "thread" being horizontal pins like a segment of a lantern-gear.
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Paul Sherriff | 31/07/2021 22:03:33 |
12 forum posts | Thanks. Very helpful and food for thought |
duncan webster | 01/08/2021 14:32:56 |
5307 forum posts 83 photos | Have you tried asking the rhdr |
Nigel Graham 2 | 01/08/2021 17:25:02 |
3293 forum posts 112 photos | I'd already suggested that, Duncan! |
Paul Sherriff | 01/08/2021 20:30:48 |
12 forum posts | Message sent to the RH&DR fingers crossed Paul |
Paul Sherriff | 26/01/2022 19:30:49 |
12 forum posts | Never did get a reply. Oh well…. |
John Baguley | 26/01/2022 19:47:44 |
![]() 517 forum posts 57 photos | The reverser is described with drawings in Volume 53, Issue 1281, Page 630. John |
Former Member | 26/01/2022 19:49:12 |
1085 forum posts | [This posting has been removed] |
Paul Sherriff | 26/01/2022 19:54:55 |
12 forum posts | Thanks John , just what I was after many thanks |
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