Patent GB-641873-A (GB)
Title: Improvements in or relating to controls for multiple engine power plants
IPC: B61C17/12
Filed: 1948-09-14
Abstract: 641,873. Regulating. FELL, L. F. R. Sept: 14, 1948, No. 24059. [Classes 7(ii) and 7 (vi)] [Also in Group XXXI] In a power plant, e.g. for a locomotive, comprising main supercharged compression ignition engines 1a-d, Fig. 1 arranged as described in Specification 628,448 so that each drives a sun wheel of a differential gearing through a variable-filling fluid coupling 2a-d having a manually operable filling control, a unidirectional device 9a-d associated with each sun wheel permitting rotation thereof in one direction only and a governor 10a-d controlling the fuel injection of each engine in accordance with a predetermined torque-speed curve as described in Specification 661,293, the control system comprises, in association with each governor 10a-d a member set by a single regulator 21, Fig. 2, to control the fuel injection and a cut-off member 11a-d operated, when a coupling control lever 22a-d disconnects its engine from the load, to reduce the engine fuel injection to the idling charge. The engines are supercharged by blowers 7x, 7y driven by auxiliary engines 6x, y, controlled by governors 14x, y, having cut-offs 15x, y, similar to the devices 11a-d. The fuel control members associated with the governors 10a-d are actuated by shafts 60f, r, rotated by a shaft 30 to which the regulator 21 is keyed and on which valve plates 31, Fig. 3 actuated by the levers 22a-d are rotatably mounted, stops on the shaft 30 preventing the levers 22a-d being moved to their coupling-filling positions when the regulator 21 is in the idling position. When a lever 22a-d is in the "OUT" position, Fig. 2, its valve 31, Fig. 3 connects a pipe 36 of, a vacuum operating system to atmosphere, whereby a cut-off device 11 is operated to reduce the corresponding fuel pump to idling, and a spring- loaded diaphragm 12 moves a cock 81 to empty the corresponding coupling 2a-d and diconnect the engine from the load. When the lever is moved to the " IN " position, the valve 31 connects pipe 36 to a vacuum reservoir 18 and the cut-off 11, is put out of action and the device 12 operated to put the engine under load. A valve 66 opens to connect the pipe 36 to atmosphere to reduce the corresponding engine to idling if the engine oil pressure acting on a piston 67 drops below a safe value. A reversing valve 43, Fig. 2, which is connected to the shaft 30 through an interlock 45 so that it can only be operated when the regulator 21 is at idling, connects one of the pipes 48f, 48r to vacuum to move a device 13 to set the transmission gearing 3 for forward or reverse running. When the regulator 21, which also operates a valve 152, Fig. 2, in the vacuum system, is at idling, the various devices are positioned as follows :-(a) the levers 22a-d are held in the " OUT " position whereby all the engine couplings are empty, and the cut-off devices 11a-d are operated to put the fuel controls at idling; (b) the valve 152 connects a pipe 154 to atmosphere so that the cut-offs 15x, y, put the auxiliary engine fuel controls to idling and vacuum-loaded valves 16x, y, are opened to release boost pressure in the manifold 8. To put the plant under load, the regulator 21 is first moved from idling, which causes the valve 152 to connect pipe 54 to vacuum, whereby the cut-offs 15x, y, are put out of operation and the blowers 7x, y, are driven at sufficient speed to supply the necessary boost pressure, the vacuum holding the valves 16x, y, closed. One of the levers 22a-d is now operated to bring its associated engine under load by causing filling of its coupling, the corresponding cut-off 11a-d being put out of action to allow the fuel supply to increase to the value set by lever 21. Further engines are put under load as required by operation of the levers 22a-d, the fuel supply to each engine being controlled by the regulator 21 and corrected by the action of the governors 10a-d. A device 17a is also actuated by the vacuum in the pipe 54,when the regulator 21 is moved from idling to put the unidirectional device 9a out of action. In a modification the unidirectional devices comprise self-wrapping brakes controlled by a vacuum operated diaphram so that the brakes are only in operation on the engines which are not supplying torque whilst the remaining engines are supplying torque. The vacuum control system may be replaced by a hydraulic or pneumatic system. Specifications 598,042, 636,808 and 661,280 also are referred to.