GB482632A - A hydraulically-operated multiple clutch change speed gear - Google Patents

Abstract

482,632. Variable - speed gearing ; friction clutches. KEGRESSE, A. Feb. 8, 1937, No. 3735. Convention date, Feb. 10, 1936. [Class 80 (ii)] In a three-speed gear comprising three hydraulically-operated friction clutches A, B and C adapted to transmit respectively low, intermediate and high speed drives from a driving flywheel 54 to nested gear-carrying shafts 44, 45 and 46, each clutch comprises a driven disc. such as 41, secured to the corresponding shaft 44 and arranged between a pair of discs 59 and 59<1> splined in the flywheel, the discs 59 and 59<1> being moved towards each other so as to grip the disc 41, against the action of retracting springs 62, by diaphragms 18 and 22 which bear against the discs 59 and 591 and which are secured over annular recesses formed in plates 57 and 58 fixed in the flywheel. Pressure fluid is supplied through passages 63 and 34 to a chamber 35 in the end plate 56 of the flywheel, and thence past a pressureresponsive spring-loaded valve 36 to a duct 66 leading to the annular recesses of the lowspeed clutch A. From these recesses, a duct 67 leads to a chamber 68 above a similar valve 69 controlling the supply through a port 70 and duct 71 to the annular recesses of the clutch B. From the latter, a duct 72 leads to a chamber 73 above another similar valve controlling the supply through a port 74 to the clutch C. The valves are mounted in members 77 detachably fitted in the periphery of the plate 56. The spring loading of the valve associated with a lower speed clutch is smaller than that of the valve associated with a higherspeed clutch, so that the clutches operate in succession as the oil pressure varies. As a valve closes, the annular recesses of the associated clutch are vented through ports 76. Each metal diaphragm is, in the disengaged condition of the clutch, flexed by the action of the retracting springs into the corresponding recess, and, when the clutch discs are new, the' application of fluid pressure restores it to its natural plane condition. As the discs wear, however, the diaphragm flexes beyond this plane condition. The Specification as open to inspection under Sect. 91 comprises also a single clutch, constructed as above, between a driven shaft and a drum secured to a driving shaft, wherein a valve movable axially in the driving shaft is adapted to put the passage 34 into communication either with a supply of pressure fluid or with a vent port. There may be more than one disc secured to the driven shaft, each such disc being arranged between a pair of oppositely-movable driving discs. This subjectmatter does not appear in the Specification as accepted.