| 摘要 |
862,409. Variable-speed gear; friction clutches. GENERAL MOTORS CORPORATION. May 26, 1959 [June 9, 1958], No. 17896/59. Class 80 (2). [Also in Group XXXIV] A vehicle overdrive transmission between an input shaft 10 and output shaft 49 carrying the input pinion 11 of a sliding-gear synchromesh unit comprises a flywheel 16 coupled by a normally engaged main clutch 20 to the planet carrier 41 of an epicyclic gear unit 42, the sun pinion 51 of which is integral with a sleeve 52, and a drum 57 common to a brake 62 carried by a fixed housing 75, and a second clutch 61, the output member of which is splined to shaft 49. Brake 62 and clutch 61 are operated by pressure liquid acting upon annular pistons 78, 68, respectively, the effective area of the lefthand side of piston 68 being less than that of the right-hand side. Liquid delivered by a pump 91 may be fed under the control of a solenoid-actuated piston valve 107 to a pipe 111 communicating by a sleeve 122 with the right-hand side of brake piston 78, and also with a chamber 126 on the left-hand side of clutch piston 68. In addition, low-pressure oil for lubrication is supplied by pump 91 through a branch 95. pressure-regulating valve 96 and pipe 102 to an axial passage 102 through shaft 49, and through a branch 127 to a chamber 128 on the right-hand side of piston 68, from which it passes to clutch 61 through a passage 129 in the piston. For direct drive valve 107 is opened and the pressure liquid acts on piston 78 to release brake 62 against its engaging spring 83, and also passes into chamber 126 to engage clutch 61. For overdrive valve 107 is closed, cutting off the pressure liquid, so that brake 62 is engaged by spring 83, and the centrifugal pressures of the liquid in chambers 126, 128 acting on differential piston 68 bias the latter to the left to release clutch 61. Engagement of brake 62 holds sun pinion 51 stationary so that the drive from shaft 10 and flywheel 16 is transmitted through the annulus 47 to output shaft 49. |
