Patent GB-661281-A (GB)
Title: Improvements in or relating to controls for the transmission gearing of multiple engine power plant
IPC: F15B21/00
Filed: 1948-09-06
Abstract: 661,281. Power plant. FELL. L. F. R. Aug 18, 1949 [Sept. 6, ,1948], No. 23403/48. Class 7(ii) [Also in Group XXXIV]. In a power plant for a locomotive of the kind described in Specification 628,448 comprising two or more supercharged compression ignition engines each driving a sun wheel of a differential gear through a fluid coupling having a manually operable filling control, a unidirectional device permitting rotation in one direction only associated with each sun wheel and a fuel governor associated with each engine, the unidirectional devices comprise self-wrapping brakes each of which is provided with disengaging means which is operated when the associated engine is supplying torque or when all the engines are idling. The operation of the power plant is controlled. as described in Specification 641,873, by a single regulator 21 controlling the fuel supply of all the engines, levers 22, one for each engine, controlling the filling of the fluid couplings and a reversing lever 23, which operate respectively valves 100. 24: and 43 in a vacuum controlling system operated from a reservoir 18. The self-wrapping brakes comprise shoes 134 carried by levers 135, 138, pivoted to a beam 136 pivoted at 137, the lever 135 being alsc pivoted to a bell crank lever 139 which is anchored at 141 and adjustably connected at 143 to a rod 142 connected to lever 138. A spring 144 tends to tilt the beam 139 clockwise to increase the contact pressure of the shoes 134 which remain in light contact with the drum 133 as long as shaft 132 rotates anticlockwise but which grip if the shaft tends to rotate clockwise. A diaphragm 111 connected to the beam 136 is actuated by vacuum in a pipe 108 to disengage the brake shoes from the drum 133. The regulator 21 also actuates a valve 117, associated with each engine, to control the application of vacuum to devices 11 maintaining the engine fuel controls at idling and to devices 12 which actuate the coupling filling mechanisms 81. With the regulator 21 at idling, all of the levers 22 are held in the OUT position and the valves 117 are set to cut off vacuum from the devices 11, 12, i.e. the couplings are empty and the fuel controls at idling. The vacuum from reservoir 18 is transmitted through pipes 104, 107, 65 to the diaphragms 111 to disengage all the brakes 134. Movement of regulator 21 from idling cuts off vacuum from the pipes 107, 65, and allows all the brakes 134 to return to their operative positions, the valves 117 being simultaneously rotated to connect pipes 109 to pipes 76. To bring any engine under load, its associated lever 22 is moved to the IN position, in which passage 38 connects. the pipe 65 to vacuum, whereby the diaphragm 111 is actuated to disengage the brake 136 of that engine and the devices 12, 11 are actuated to fill the coupling and move its fuel controls to the operative position respectively. A valve 66 in each pipe 65 is held closed by the oil pressure in the lubricating system when the associated engine is running, and opens the pipes 108, 109 to atmosphere to disconnect the engine from the load if the oil pressure drops below the normal operating value. The reversing valve 43 connects either pipe 48f or 48r to the pipe 107 so that a vacuumactuating reversing gear is operated when the regulator 21 connects the pipe 107 to vacuum in its idling position. Specifications 598,042, 661,280, and 661,293 are referred to.