GB540855A - Improvements relating to power plants comprising a plurality of air or gas compressors or gas generators, and particularly free piston compressors or gas generators - Google Patents

Abstract

540,855. Air and gas compressors and gas generators. PESCARA, R. P. Nov. 11, 1939, No. 29892. Convention date, Nov. 12,1938. [Class 8 (i)] [Also in Groups XXVII and XXXI] A power plant comprises a set of compressors or gas generators, especially free piston machines, each driven by its own internal combustion motor, the number of compressors &c. in use being varied in accordance with the power required, and the fuel supply to the motors being regulated so that each compressor in action develops the same fraction of its maximum power. The invention is shown applied to a locomotive having five compressors A<SP>1</SP> ... A<SP>5</SP>, Fig. 1. The fuel pump delivery may be controlled by a lever 11, Fig. 2, controlled by a piston 12 subject to the pressure of the delivery manifold 5. Fig. 3 shows means for automatically varying the number of compressors in use in accordance with the pressure in the manifold 5 by allowing this pressure to act on a piston 88 controlling a valve 87 by which compressed air from a pipe 86 may be delivered either to a starting motor 85 or a stopping motor 84 which act on camshafts 83, 82 to operate valves 76 controlling the connection of pipes 77, leading to control cylinders, with compressed air and discharge pipes 78, 79. Fig. 5 shows a device in which a number of compressors can be started by hand, and this number automatically reduced in accordance with the manifold pressure. This pressure acts on a piston 95 to actuate a lever 113 and open a valve 109 to allow air pressure from a pipe 112 to start a motor 108 and rotate a camshaft 107. The first cam to strike a rocker opens a corresponding pressure valve 100<SP>1</SP> normally held closed, and closes a discharge valve 99<SP>1</SP> thus admitting compressed air to a slide valve d' which is then in position to deliver the air to a piston 90<SP>1</SP> and so reverse the starting handle and stop the corresponding compressor. The lever 113 is acted on by spring-pressed abutments 114<SP>1</SP> . . . which oppose its movement, the delivery of those compressors which are in action acting on abutments 115<SP>1</SP> of the springs to release the lever from a corresponding number of abutments 114<SP>1</SP> so that the sensitiveness of the regulating action increases with the number of compressors in action. Thus when any compressor is stopped, the engagement of the corresponding abutment brings the lever 113 back into neutral position, closing the valve 109. If the delivery is still excessive the pressure again rises and a second &c. compressor is cut out. The motor 108 is however still operated by air supplied through non-return valves 118<SP>1</SP> till the corresponding cam has been released and the slide valve freed from pressure. Fig. 2 shows a hand starting device in which when the handle 15 is put in the position shown, a valve 41 is first opened admitting compressed air from a pipe 43 to pass into a cylinder 45 raising a piston and causing a cam 49 on its rod 48 to open a valve 54. Compressed air from a pipe c then passes through a valve 30 in a piston 28 into a cylinder 25, and also to a cylinder 56 causing its piston to push a rod 58 out of the path of the rod 48 which rises further, opening a valve 66 to atmosphere and so releasing pressure behind the piston 28, which rises and opens a valve 26 allowing air from the cylinder 25 to pass to an accumulator 24 and bring the synchronized motor pistons 18 and their connected compressor pistons 22, 23 together. Reversal of the handle 15 closes the valve 41 the stem of which has a bleed slot which in this position empties the cylinder 45 ; its piston falls, opening a valve 59 by which compressed air passes to raise a piston 35 on the push rod of the fuel pump 9 thus stopping this pump. Air flows from cylinder 36 to a cylinder 38 raising a piston 40 and rod 37 and putting the system into starting position ; the piston 40 uncovers a port conveying air to a cylinder 63 and so releasing a stop 65 from the path of the rod 48 which completes its stroke, opening valve 68 and supplying cylinder 36. Each compressor may have a gauge 70 and a counter 71 for hours worked, the counter being operated through a clutch actuated by a piston subject to the first stage of compression.