Patent GB-639840-A (GB)
Title: Improvements in change speed gearing comprising hydraulically operated clutches
IPC: F16D48/02
Filed: 1947-03-25
Abstract: 639,840. Hydraulically-operated friction clutches controlling change-speed gearing. PONCET, P. March 25, 1947, No. 8135. Convention date, March 28, 1946. [Class 80 (ii)] In a constant-mesh or other change-speed gearing having hydraulically-operated clutches, a feeder head 13, Fig. 4, is rotatably and slidably housed within a sleeve 17 tightly secured in the axial bore of the shaft 1 carrying the clutch or clutches to be operated, the sleeve 17 being provided with ports 18 communicating with conduits 11 leading to the clutch or clutches. With this construction, leakage from the head 13 is minimized as the sleeve 17 is not subject to mechanical deforming stresses and forms a unit easily ground accurately to fit the head. As shown, a gear 5 revoluble on a shaft 1 is clutched thereto by gripping side plates 5a on the gear frictionally between a plate 7 and a piston 3, the former fixed to the shaft and the latter slidably splined to a cylinder 2 on the shaft and movable under fluid pressure. As arranged to control a countershaft gear the clutches are duplicated and energized alternately by a feeder head 13 supplying ports 18, 181 and conduits 11 or 11<1> from a cylinder 23 through passages 25, 24, 16 and 14. Leakage between the sleeve and shaft is prevented by packing 19, which may be housed in recesses in the shaft 1 as shown or placed directly between the sleeve and shaft. Pressure fluid is always supplied through a port 26 to the right hand side of a piston 22 controlling the head 13, movement of which to the right is effected by the admission of fluid through a port 27 to the left hand side of the piston 22 which has a greater effective area than the right hand side. Driving and driven shafts 28, 29, Fig. 5, carry gears 34, 35 and 36, 37 meshing countershaft gears 30 ... 33 mounted in pairs which are selectively clutchable to the countershaft 1 as described above to give four indirect speeds. The shafts 28, 29 are coupled for direct drive by a clutch 38 comprising a flange 44, Fig. 6 on the shaft 28 gripped between a flange 40 rigid with a cylinder 39 on the shaft 29 and a piston 42 operated hydraulically through a non-sleeved feeder head 13. If the shaft 29 has no free outer end, fluid may be supplied by means of a stuffing box. A number of clutches mounted on the same shaft and fed through ports 18 ... 183, Fig. 7, may be supplied one at a time through a single slider head 13 by utilizing, in addition to a main hydraulic piston 22 of the kind shown in Fig. 4, auxiliary hydraulic pistons 48, 49 arranged to abut a plate 45 on the shaft 15 when the respective cylinders 46, 47 are supplied with fluid and so limit the travel of the head 13 as required. Multiple slider heads 13a, 13b, 13c, Fig. 8, may be used to supply pairs of clutches simultaneously. Ports 182 or 183 are supplied continuously through head 13c whilst ports 18, 181 are connected to supply alternatively through head 13a or head 13b as the case may be. The Specification as open to inspection under Sect. 91 describes also an epicyclic change-speed gear comprising two three-element trains 52, 53, 55 and 63,64,66, Fig. 9 (Cancelled), in series, the intermediate shaft 54 connecting the driven planet carrier of the first gear and the driving sun of the second gear housing a non-sleeved feeder head 13 alternatively feeding clutches 61, 71 locking the first and second trains solid. Hydraulically-operated brakes 58, 69 station the respective gearing reaction members for epicyclic driving. This subject-matter does not appear in the Specification as accepted.