If you register, you can do a lot more. And become an active part of our growing community. You'll have access to hidden forums, and enjoy the ability of replying and starting conversations.

Valve Gear Varieties

Discussion in 'Steam Traction' started by M Palmer, Feb 27, 2019.

  1. M Palmer

    M Palmer Guest

    I was trawling through Google Patents for some information on some of the more obscure valve gear varieties and I had a fair bit of success. I thought I'd post my "finds" here and hopefully start a discussion on these also-rans and why they didn't take off like Walschaerts.

    Bryce-Douglas (tried out on Caley 124):
    https://patents.google.com/patent/U...1&after=priority:18860101&oq=link+motion+1886

    Isaacson (E&WJR 17 & 18):
    https://patents.google.com/patent/US915224A/en?inventor=Horace+Sanderson

    Morton (GER G14 644):
    https://patents.google.com/patent/US281548A/en?q=morton&q=valve&q=gear&oq=morton+valve+gear

    J. T. Marshall (both turn of the century GNR & LD&ECR:
    https://patents.google.com/patent/US714213A/en?inventor=James+Thompson+Marshall
    ...& later of SR N class 1850 fame):
    https://patents.google.com/patent/US1760952A/en?inventor=James+Thompson+Marshall

    W. M. Smith compound valve gear (+ some other Smith patents):
    https://patents.google.com/patent/US736889A/en?inventor=Walter+Mackersie+Smith

    https://patents.google.com/patent/U...oq=inventor:(Walter+Mackersie+Smith)+cylinder
    https://patents.google.com/patent/US662578A/en?inventor=Walter+Mackersie+Smith

    Younghusband (NER):
    https://patents.google.com/patent/US703885A/en?inventor=Samuel+Smith+Younghusband

    I also found all sorts of weird & wonderful valve gear variations. A list of highlights follow:

    https://patents.google.com/patent/US1749408A/en?q=benton&q=valve&q=gear&oq=benton+valve+gear

    https://patents.google.com/patent/U...ar&inventor=blanchard&oq=blanchard+valve+gear

    https://patents.google.com/patent/US1582877A/en?q=elliot&q=valve&q=gear&oq=elliot+valve+gear

    https://patents.google.com/patent/U...gear&inventor=hathaway&oq=hathaway+valve+gear

    https://patents.google.com/patent/U...gear&inventor=hathaway&oq=hathaway+valve+gear

    https://patents.google.com/patent/US1748844A/en?q=valve&q=gear&inventor=kupka&oq=kupka+valve+gear

    https://patents.google.com/patent/US1801752A/en?q=mueller&q=valve&q=gear&oq=mueller+valve+gear

    https://patents.google.com/patent/US1249534A/en?q=smith&q=valve&q=gear&oq=smith+valve+gear

    https://patents.google.com/patent/U...gear&before=priority:19500101&sort=old&page=1

    https://patents.google.com/patent/U...ity:19370220&after=priority:19370201&sort=old

    https://patents.google.com/patent/US2416982A/en?inventor=dekle&before=priority:19500101&sort=old

    https://patents.google.com/patent/U...gear&before=priority:19100101&sort=old&page=1

    https://patents.google.com/patent/U...ity:19330101&after=priority:19320101&sort=old

    Hopefully these are of some interest.
     
  2. PoleStar

    PoleStar New Member

    Joined:
    Nov 10, 2018
    Messages:
    75
    Likes Received:
    42
    Gender:
    Male
    Location:
    West Midlands
    Heritage Railway Volunteer:
    No I do not currently volunteer
    Well if nobody else is going to start, then I will - I would suggest that few if any of these "alternative" valve gears showed any significant advantage over the conventional types and this is why they were not generally adopted. Another point is that long-term testing has always been a problem with steam locomotives - somebody invents a valve gear, or other improvement, persuades a railway company with great difficulty to give it a try, and when the experiment does not produce brilliant results straight away, the idea is abandoned.
     
  3. RLinkinS

    RLinkinS Member

    Joined:
    Nov 8, 2008
    Messages:
    912
    Likes Received:
    928
    Gender:
    Male
    Heritage Railway Volunteer:
    Yes I am an active volunteer
    The Marshall valve gear on N 1850 apparently worked well at low speed but a knock was noted at speeds of 50 to 55 mph. When the loco was tried on a semi fast train the RH valve gear disintegrated. This information is from D L Bradley's book
     
  4. LesterBrown

    LesterBrown Member

    Joined:
    Jan 20, 2009
    Messages:
    995
    Likes Received:
    761
    Location:
    Devon
    Ahrons was of the opinion that the excessive coal consumption of the first British loco with Walschaerts valve gear' was probably due to inaccurate setting of the valves by running shed fitters to whom it was a complete novelty.

    Any alternative valve gear would likely cause similar maintenance problems.
     
  5. D6332found

    D6332found Member

    Joined:
    Dec 3, 2016
    Messages:
    361
    Likes Received:
    179
    Gender:
    Male
    Location:
    Dinting
    Heritage Railway Volunteer:
    No I do not currently volunteer
    I know it won't fit, but a Gresley/Caprotti hybrid on the P2 would be .....
     
  6. M Palmer

    M Palmer Guest

    I think the nail has been hit on the head with the above points with experiments not producing quick results and novelties on shed seeming to have been short-lived.

    I have to confess that J. T. Marshall gear is a bit of a guilty fascination of mine.

    Regarding the J. T. Marshall gear on 1850, I have read that the failure mentioned by RLinkinS wasn't immediately fatal to the endeavour but the untimely death of Marshall was. Whether this was because of legal issues regarding the patent or because Marshall was no longer on hand for technical support as it were, I have no idea. Possibly both?

    While on the subject of J. T. Marshall gear and the Southern, I have seen it written that the Maunsell Z class had a "custom" gear on the inside cylinder and some (T. H. Shields in his "The evolution of locomotive valve gears") have described this as Marshall gear. Certainly the description of the gear in the December 1930 Locomotives Carriages Wagons etc. Shields references would fit the description of Marshall's 1901 gear and the diagram of the Z class within shows a gear not at all dissimilar to the drawing of the Marshall gear fitted to LD&ECR No. 26 that is available at the NRM. The cylinder inclines are similar, 1-in-8 on the Z & 1-in-9 on 26.

    I could very well be mistaken. There is a fair bit of drawing in the way on the Z class inside cylinder and the gear settings are different but the resemblance is striking.

    If my assertion is correct, could the success of 1901 (there is also a similar 1907 patent) J. T. Marshall valve gear on the Z class have led Maunsell to consider giving the 1926 variant a go on 1850?

    For clarity, I use the year the patent was filed as that was when it was in the bag as it were, rather than the year it was granted.

    ETA: Both Holcroft & Bulleid commented on Shields's paper and neither refuted his claim that it was fitted to the inside cylinder of a 3-cylinder 0.8.0 of the Southern. Surely they would know?
     
    Last edited by a moderator: Mar 2, 2019
  7. M Palmer

    M Palmer Guest

  8. PoleStar

    PoleStar New Member

    Joined:
    Nov 10, 2018
    Messages:
    75
    Likes Received:
    42
    Gender:
    Male
    Location:
    West Midlands
    Heritage Railway Volunteer:
    No I do not currently volunteer
    The inside gear on the Southern Z class (and on the 3 cylinder Moguls) was basically Walscheart's but with a second eccentric to drive the combination lever as there was no space to drive it from the crosshead. This is clearly not the same as the JT Marshall gear fitted to the outside of no. 1850, which may have had two eccentrics (or return cranks) but it also had a conventional combination lever. I would like to know more about it, but I have never seen a good drawing or explanation.

    I would have thought that the knocking and breakage of the gear in service could have been overcome with a bit of development - it is the sort of thing which happens on prototypes, and suggests a design fault. Marshall's death must have been a factor.
     
  9. M Palmer

    M Palmer Guest

    Last edited by a moderator: Mar 2, 2019
  10. M Palmer

    M Palmer Guest

    OK if anybody thinks I'm infringing copyright, please, please feel free to tell me & I'll take this down. The following has been (crudely) cropped to only show the relevant sections.

    Z class diagram (source: Locomotive Magazine and Railway Carriage and Wagon Review, December 1930):

    [​IMG]Z by Matthew Palmer, on Flickr
     
    Last edited by a moderator: Mar 3, 2019
  11. Eightpot

    Eightpot Resident of Nat Pres Friend

    Joined:
    Aug 10, 2006
    Messages:
    8,077
    Likes Received:
    2,264
    Gender:
    Male
    Occupation:
    Engineer Emeritus
    Location:
    Aylesbury
    Heritage Railway Volunteer:
    Yes I am an active volunteer
    From what I can make of it, on the Z class the piston valve was alongside the cylinder which resulted in the piston rod/crosshead assembly being some distance away from the valve spindle. This I believe to be the reason for the 2nd eccentric to operate the (much shortened) combination lever.

    Edit. Was this same arrangement used on the 3-cylinder N1 and U1s when converted from Gresley 2 : 1 gear to 3 sets of Walschaerts?
     
  12. PoleStar

    PoleStar New Member

    Joined:
    Nov 10, 2018
    Messages:
    75
    Likes Received:
    42
    Gender:
    Male
    Location:
    West Midlands
    Heritage Railway Volunteer:
    No I do not currently volunteer
    Matthew,

    Many thanks for posting the excellent diagrams. I have just found my copy of Shields...

    The Z class uses 1 eccentric to drive the expansion link and a second to drive a short but fairly conventional combination lever. The 1901 gear uses the second eccentric to oscillate the expansion link trunnion, so the two gears are not identical, though similar in principle. The other two drawings seem to be versions of the 1901 idea, but with swinging links instead of a sliding trunnion.

    The gear used on SR no. 1850 was different. This engine had separate inlet and exhaust valves with the aim of improving efficiency, and the valve gear is basically Walscheart's adapted to control the two sets of valves independently, hence it has two expansion links.
     
    Last edited: Mar 2, 2019
    M Palmer likes this.
  13. Jimc

    Jimc Part of the furniture

    Joined:
    Sep 8, 2005
    Messages:
    4,052
    Likes Received:
    4,665
    Occupation:
    Once computers, now part time writer I suppose.
    Location:
    SE England
    Heritage Railway Volunteer:
    No I do not currently volunteer
    What did Gresley have to do with it?
    Designing a better valve gear and getting rich on the royalties seems to have been a 19thC dream. We may note the classic Churchward quote after inspecting Holcroft's first model of his conjugating gear, which IIRC was on the lines of "Now young man, all you need to do is work out a way of using one set of valve gear on a two cylinder locomotive and your fortune's made."
     
  14. M Palmer

    M Palmer Guest

    PoleStar, many thanks for the clarification!

    While we are on the subject of constrained 3-cylinder valve gears, does anybody have or can point me to a diagram of Stanier's 3-cylinder 2-6-4T valve gear arrangement?
     
  15. M Palmer

    M Palmer Guest

    Just for reference, here's the 1850 diagram. Edit: Removed.
     
    Last edited by a moderator: Mar 3, 2019
    PoleStar likes this.
  16. Big Al

    Big Al Nat Pres stalwart Staff Member Moderator

    Joined:
    May 30, 2009
    Messages:
    21,072
    Likes Received:
    20,779
    Location:
    1016
    Heritage Railway Volunteer:
    No I do not currently volunteer
    On copyright, for @M Palmer , if the material is freely available on the web already then it is public. If it belongs to a book then the source should be acknowledged when it is posted.
     
  17. Jimc

    Jimc Part of the furniture

    Joined:
    Sep 8, 2005
    Messages:
    4,052
    Likes Received:
    4,665
    Occupation:
    Once computers, now part time writer I suppose.
    Location:
    SE England
    Heritage Railway Volunteer:
    No I do not currently volunteer
    'Fraid not. Just because its been posted on the web doesn't mean its fair game.
     
    andrewshimmin and Forestpines like this.
  18. agalpin

    agalpin Member

    Joined:
    Apr 22, 2006
    Messages:
    292
    Likes Received:
    12
    Location:
    Bleeding 'ell Essex
    This thread made me try to look up a valve gear I experienced many years ago on an OL49 called Tropanoff I think?
    Anyone else come across it or have any links to information please?

    Whilst driving you would coast in full gear and upon stopping, you had to wind into mid gear, snap open and shut the regulator to “reset” the valves before winding back into full gear to get underway again. Quite labour intensive.
     
  19. LMS2968

    LMS2968 Part of the furniture

    Joined:
    Sep 1, 2006
    Messages:
    2,987
    Likes Received:
    5,084
    Gender:
    Male
    Occupation:
    Lecturer retired: Archivist of Stanier Mogul Fund
    Location:
    Wigan
    Heritage Railway Volunteer:
    Yes I am an active volunteer
    Wasn't that the type of valve rather than valve gear?
     
    agalpin likes this.
  20. PoleStar

    PoleStar New Member

    Joined:
    Nov 10, 2018
    Messages:
    75
    Likes Received:
    42
    Gender:
    Male
    Location:
    West Midlands
    Heritage Railway Volunteer:
    No I do not currently volunteer
    Trofimoff.
     
    agalpin likes this.

Share This Page