GB193094A - Improvements in and relating to clutch mechanism - Google Patents

Abstract

193,094. Sitney, M. Oct. 17, 1921. Clutches, claw and friction; controlling reversing-gearing; operating clutches; reversing-gearing.-In combined friction and positive clutches, particularly applicable to reversing-gearing, both are actuated by fluid-pressure pistons, and control means are so arranged that the positive clutch can be, and preferably is automatically, put into engagement after the friction clutch, and vice versa for disengagement. In one form, shown in Figs. 3 and 5, a cylinder 36 is secured to a driving-shaft and a barrel 33 to a driven shaft. A clutch member 35 is splined by keys 63 to the part 36, and is guided in the part 33 by an extension 42. The member 35 is coned at one end to co-operate with the coned part 39 of the barrel 33, and has at the other end two radial slots 47 and a chamber 47<a> receiving respectively clutch blocks 48 and actuating-toggles 52. The toggles can be straightened by movement of a rod 51 to thrust out the blocks 48, which preferably run on ball or roller bearings 49, into engagement with shoulders 37 of the barrel 33. The coned parts of the members 33, 35 may come into direct frictional contact, but preferably have interposed between them a renewable floating ring 38, flanged as shown at 40 so that it is withdrawn with the member 35, which movement is limited by a dismountable ring 41. The part 36 has a bore 59 to receive a long piston 56 connected to the rod 51, and a counterbore 60 to receive an annular piston 57 connected bv tie-rods 58, Fig. 5, to the member 35. The cylinder head 61 is also bored to take the piston 56. The cylinder 36 runs in a bearing 64 provided with grooves 65, 66, communicating respectively with fluid passages 67, 68 and 69, 70, of which the passages 67, 70 are larger than the passages 68, 69, whereby the desired sequence of operation is automatically attained. A reversing-gear embodying two such clutches 25, 26 is shown in Fig. 1. The shaft 15 of a driving-motor, such as a steam-turbine, carries a pinion 22 driving a spur-wheel 20, which meshes with a similar wheel 21. The shafts 16, 17 of the wheels 20, 21 are connected respectively to the driving-members of the clutches 25, 26, the driven members being connected to shafts 23, 24 carrying pinions 27, 28 meshing with a common driven spur-wheel 29. The pinion 22 may be replaced by pinions 30, 31 of different diameters, driven, say, by high and low pressure turbines, and engaging respectively the meshed wheels 20, 21. The grooves 65, Fig. 3, in the bearings 64 of the clutches 25, 26 are connected by a pipe 82, and the grooves 66 thereof communicate by pipes 81, 80 with the ends of a pump 76, the piston 78 of which is in tandem with the piston 77 of a steam or other fluid-pressure actuating-cylinder 75 controlled by a cock 79. In the position shown, the clutch 25 is in engagement, and in order to reverse the wheel 29, the cook 79 is thrown over, whereby the oil or other fluid in the pump 76 is propelled through the pipe 81 to disengage the positive and friction clutches 25, thereby displacing the fluid therein along the pipe 82 to engage the friction and positive clutches 26 and to propel the exhaust fluid therein through the pipe 80 to the pump. Leakage is made up from a tank 87 through check valves 85, 86 and pipes 83, 84. Instead of making the passages 67, 70 and 68, 69, Fig. 3, of different bores, they may lead each into a separate groove in the bearing 64, the supply pipes being branched and each branch having an independent cock to control the sequence of operation, or to permit-the friction clutch to be used alone. In a modification, Figs. 13 and 14, the cone clutch is replaced by a cup-shaped frame 110<a>, which is splined to the cylinder 36 and has dovetailed recesses 112 containing ribbed friction blocks 113. The thin bottoms of the recesses are slotted to make them springy and are so inclined that, when the piston 57 thrusts the member 110<a> inwards, the blocks 113 are pushed out into engagement with the corrugated surface 109 of a split member 105 bolted to the barrel 33. The recesses 112 taper also in width, so that the blocks are positively withdrawn with the member 110<a>, axial motion of the blocks being prevented by the corrugations. The wall 114 is detachable to enable the blocks to be inserted.