| 摘要 |
940,330. Motor vehicle transmission gearing. EATON AXLES Ltd. May 17, 1962 [June 1, 1961], No. 19038/62. Heading B7H. [Also in Division F2] In a vehicle transmission comprising two multi-speed axles 11, 12 connected in tandem through an interaxle differential 73 the driving ratios of the two-speed epicyclic gears sets (Fig. 3) incorporated in each axle are separately selectable by a control system (Fig. 5) to provide three different transmission ratios, i.e. with both axle gear sets in low ratio, with one gear set in low ratio and the other in high ratio, or with both gear sets in high ratio. The gear set 14 of the axle 12 includes a crown gear 22 formed with internal teeth 34 meshing with planet gears 29 on a carrier 23 driving halfshafts 24, 25 through differential gearing 27, 28. A sun gear 32 meshing with the planet gears 29 is carried by a sleeve 33 which is axially displaceable between a low ratio position wherein the sun gear 32 is held stationary by engagement of teeth 36 on the sleeve with teeth 37 on a housing 18 and a high ratio position wherein the sun gear engages teeth 38 on the carrier 23. Ratio selection is effected by an air pressure cylinder 44 actuating a lever 40 resiliently connected through torsion springs (Fig. 6, not shown) mounted on a shaft 42 to a fork 39 engaging the sleeve 33. A similar epicyclic gear set 13 on the axle 11 is provided with a crown gear 53 (Fig. 2) and an air pressure cylinder 107 (Fig. 5). The interaxle differential 73 comprises input bevels 59 carried by a ring 74 secured to an input shaft 55 and output bevels 72, 75 respectively connected by gears 69, 68 to a pinion 19 driving the crown gear 22 and by a shaft 57 and a connecting shaft 58 to a pinion 52 driving the crown gear 53. A dog-clutch 79 splined to the input shaft 55 may be engaged with the gear 69 to prevent differential action between the axles 11, 12 by an actuator 136 linked to an air pressure cylinder 134. For lubrication purposes a housing 56 enclosing the differential 73 is formed with a trough 83 which supplies oil thrown thereinto from the gear 69 to the differential through a passageway 84 and openings formed in the shafts 55, 57. As shown in Fig. 5 springs 104 acting on the levers 40 normally retain the gear sets 13, 14 in low ratio until compressed air from a source 103 is supplied to the cylinders 44, 107 to select high ratio through solenoid valves 112, 114 energized by a selector switch 137 which may energize the valve 114 alone or both valves 112, 114 together. When the gear sets 13, 14 are in low ratio so that contacts 166, 167 associated with one lever 40 are closed the dog-clutch 79 may be engaged to lock the differential 73 by closing a switch 162 to open a solenoid valve 132 which supplies air to the cylinder 134 and also to a pressure responsive switch 151 which isolates the selector switch 137 to prevent high ratio selection while the differential is locked. |
