Patent GB-493703-A (GB)
Title: Improvements in or relating to hydraulic power transmitters
IPC: F16D33/14
Filed: 1937-04-08
Abstract: 493,703. Hydraulic power transmitters. SINCLAIR, H., and BASEBE, A. C. April 8, 1937, No. 10067. [Class 69 (ii)] A hydraulic power transmitter of the kinetic type comprises a working chamber including driving and driven vaned elements, a rotatable reservoir chamber which is coaxial with said working chamber and which has an effective capacity at least of the order of 50 per cent of the normal maximum liquid content of said working chamber, a drain passage which is adapted to exhaust at least a part of the liquid content of said working chamber to said reservoir chamber under the influence of the energy of motion of the working liquid and which is incapable of being closed while said chambers are rotating, a scoop disposed in said reservoir chamber, and a filling passage which is separate from said drain passage and which leads from said scoop to said working chamber. In one form, Figs. 1 and 2, the scoop tube 43 can be rocked about an axis 46 eccentric to the axis of rotation of the impeller 10 and runner 15 ; movement of the scoop tube is effected by a lever 47 which can be latched to a quadrant 49, the scoop tube being urged to extended position by a weight 54. Liquid discharges from the working circuit through leak-off ports 42 into the reservoir chamber formed by a pressed and rolled steel casing 40 welded to the impeller ; the end wall 41 is bulged for rigidity; a filling plug 83 is provided; a bulge 82 receives the mouth of the scoop tube when the latter is in extended position. The groove 82 may alternatively be shallow so as to accommodate only the lip portion of the scoop tube at the radially outermost edge of the mouth. In operation, liquid discharges from the working circuit and forms an annular ring in the reservoir ; if the scoop tube be adjusted so that its mouth dips into this ring, liquid is scooped and passes through ports 56, 57, duct 58 and union 61 to an external cooler and thence by union 62, duct 59, port 60, groove 63 and ducts 64 in the runner boss to the working circuit ; the cooler may be omitted, duct 57 then communicating directly with port 60. Cooling is effected owing to the features that the back of the impeller 10 is unshrouded, and that the jets of liquid issuing from the leak-off ports 42 impinge on the reservoir wall 40 which is exposed to the atmosphere ; the scoop tube agitates the liquid in the reservoir and causes it to scour the wall 40. A byepass orifice 85 may be provided in the scoop tube to fling a jet against the end wall 41 which otherwise is not wetted. The end wall 41 carries an accurately turned and faced ring 80 co-operating with a similar facing 81 on the fixed bracket 20, these forming a means for checking, by feeler gauges and a straight edge, the alignment and the axial relationship of the fixed sleeve 19 and the driving parts of the coupling. Axial spacing of the impeller and runner is maintained by a rod 23 fixed at 24 to the runner shaft, and carrying at the other end a bi-directional thrust bearing 26 secured in the impeller boss. The end of the runner shaft is mounted in the impeller boss by a self-aligning bearing 22. The runner shaft has thrower rings 70 working in a groove 71 communicating by duct 72 with the reservoir chamber. The aperture in the end wall 41 is packed by a labyrinth comprising a tube 73 and a diaphragm 74, having ports 75, both carried by the said end wall, and a disc 76 carried by the manifold sleeve 19 ; the latter is provided with grooves 77. The flange 31 of the output shaft 30 carries compressed rubber bushes 32 with inner steel sleeves 33, pins 34 securing it to the flange 35 of the runner shaft. In a modification, Fig. 3 (not shown), a coupling having emptying means as described in Specification 378,726 is provided with a scoop tube rotatably adjustable from outside by means of a gear wheel. In a modification, 'Fig. 4, the coupling has drain ports 42b and in addition rapid-emptying valves 111 as described in Specification 470,056 ; an auxiliary scoop tube 110, carried by the main scoop tube 43, supplies the control liquid for holding the valves closed. In a modification, Fig. 7, adapted for use as an automatic starting clutch for a 3-phase electric motor, the scoop tube control pin 45 carries a crank arm 47c movable between stops 131, 131a ; the scoop tube 43 is biassed by a spring 133, acting through link 132, to the full line position ; initial filling is thus relatively slow so that the motor can accelerate rapidly ; as the speed of the motor approaches synchronism, the tube 43 is moved by the action of the ring of liquid into the dotted line position, so that filling now takes place rapidly ; the spring bias is less effective in this position of the parts, so that the scoop tube remains in this position during running of the motor. The scoop tube may carry a vane. In a modification, Fig. 10, also adapted for use as an automatic starting clutch, a fixed scoop tube 43d is provided ; the mouth of the scoop is adjacent to the peripheral wall of the reservoir chamber, and the size of the mouth is restricted so as to delay filling. In the constructions of either Fig. 7 or Fig. 10 the peripheralleak-off ports may be omitted and the clearance space between the impeller and runner relied on for exhausting. Fig. 8 shows a modification suitable for controlling the connection of one of a plurality of marine engines to a common propeller shaft. Assuming the engine to be stationary, the needle valves 146 are shut ; rotation of the shaft 18e by another engine causes the runner 15e to circulate liquid around the vortex; it is thus raised to the top of the coupling, and passes down between the vanes of the stationary impeller 10e, and is diverted by baffle 143 into port 142, passage 141 and duct 59e whence it is withdrawn by a pump 144 and forced via duct 58e and scoop 43 into the now stationary reservoir 40e; the coupling is thus emptied, and the engine disconnected from the shaft 13e. To start the engine, the valves 146 are opened and the pump 144 run in the opposite direction. During the above operations the valve 145 associated with a cooler 140 is closed. When the coupling is full, and the engine is running, control of the filling is effected by rocking the scoop tube 43. Fig. 9 (not shown), illustrates a further modification. According to the Provisional Specification, the scoop tube may be rocked by a governor mechanism responsive for example to the speed of the driven shaft ; the governor may comprise a centrifugal pump impeller mounted on the driven shaft within a chamber formed in the manifold sleeve and having its discharge port connected to a cylinder with piston linked to the scoop-tube control member, a control spring being provided to oppose the piston. A telescopic scoop tube may be used in place of the rocking scoop tube. The scoop tube may be adapted to rotate about the coupling axis at a speed lower than that of the rotating chamber. Any other convenient liquid transfer device may be employed, for example a liquid transfer member which can rotate continuously about the coupling axis, but which can be retarded to cause it to engage liquid and transfer it back to the circuit. Alternatively means may be provided for admitting gas under pressure to the reservoir chamber to fill the circuit and for exhausting the gas to cause the circuit to empty. Again, a scoop tube may be used leading to a valve controlling the return of liquid to the circuit. Two hydraulic power transmitters may be disposed coaxially with a common rotary reservoir chamber in such a manner that the working circuits may be alternatively emptied or filled. Specifications 328,028, [Class 69 (ii)], 411,140, and 450,466 also are referred to.