The Ruston patent 3-speed gearbox
The Ruston patent constant mesh gearbox was used in all chain drive narrow gauge designs until the hydraulically activated and hydrostatic gearboxes took over with the LB and LF designs respectively. This unit made the driving of Ruston locos very easy since the clutch and gear change were combined in one lever operation and enabled the driver to operate the loco whilst walking alongside. This was a great advantage over types such as Motor Rail locos when shunting and negotiating complicated trackwork where points have to be set along the route. CLICK HERE for notes explain how it works.
Below is an extract from the R&H parts book for early Ruston engined locos and shows the gearbox casing parts.
|DL170||Gearbox top & bottom halves with nuts & studs|
|DL171||Housing for sprocket shaft bearings|
|DL172||Seat for driver|
|DL173||Reversing gear casing - bottom half|
|DL174||Bevel pinion shaft housing|
|DL176||Reversing gear casing - top half|
|DL177||Rear end cover|
|DL178||Cover for end of layshaft|
|DL179||Bolt & nut for seat|
|DL180||Cover for top half of reversing gear casing|
|DL181||Cover for clutch operating spring|