Patent GB-191111527-A (GB)
Title: Improvements in Methods of Raising or Forcing Liquids and in Apparatus therefor.
Inventor: HUMPHREY HERBERT ALFRED
Filed: 1911-05-12
Granted: 1912-05-13
Abstract: 11,527. Humphrey, H. A. May 12. Direct explosion apparatus. - Relates to internal-combustion pumps of the type having liquid pistons or columns of liquid set in motion by the expansion of an ignited combustible charge wherein the return movements of the column effect the compression of the charge, and consists in the use of a solid piston interposed between the liquid and the gas for the purpose of controlling the inlet and exhaust valves of such pumps. In the arrangement shown in Fig. 1, operating on a four-stroke cycle, the piston 1 carries a tube 12 which is provided with a buffer spring 13 at the bottom. A valveoperating rod 14, having a cam-surface 17 at the upper end, passes through a gland in the cylinder cover into the tube 12. At the end of a downward movement on the explosion stroke, the piston 1 comes into contact with a spring 15 carried by the rod 14 and forces the rod downwards, whereupon the cam-surface 17 opens the exhaust valve 4 and locks the inlet valve 5 shut by means of the mechanisms shown. Scavenging - air is simultaneously admitted through the valves 6. During the return movement of the piston on the exhaust and cushion stroke, the rod 14 remains in its lower position until it is raised at the end of the stroke by contact with the spring 13, whereupon the cam 17 allows the exhaust valve 4 to shut under the action of its spring and simultaneously sets free the inlet valve 5. The compressed cushion of gas now expands and effects the admission stroke, which is not long enough to cause the cam 17 again to operate the valves. The return compression stroke then occurs and the cycle is repeated. A spring buffer 11 is provided to prevent concussion between the piston and the lower end of the combustion chamber. Various modifications and constructional details are described, as follows. (1) The valves may be operated by cams, tappets, direct contact with the piston, or by fluid - pressure devices controlled by the piston. (2) Various buffer, cushion, or spring checking-devices may be fitted to bring the piston to rest before the liquid column has ceased moving. (3) After the piston has been brought to rest in this manner, scavenging - air, combustible mixture, or both, may be drawn in below it by the further movement of the water, and the gas so introduced may be forced through suitable passages or valves into the space above the piston on the return of the water column. (4) The exhaust valve may be fitted at the bottom of a pipe dipping into the combustion chamber and a hole formed in the piston beneath this pipe so that the piston can rise above the level of the exhaust valve. (5) Scavenging-air or combustible mixture may be introduced in a downward direction so as to form a dense layer below the hot products of combustion, and the piston may be cup-shaped so as to retain such dense gas. (6) Scavenging - air may be introduced tangentially, and the exhaust gases may be conducted from the top of the combustion chamber through a passage leading to an exhaust valve at a lower level controlled by the piston. (7) A pump may be connected to the piston for compressing scavenging - air and fresh combustible mixture, and means may be provided for regulating the quantity of charge admitted to the chamber in such an arrangement. (8) Double-acting buffers to check the motion of the piston on both up and down strokes and to start the return movements thereof may be fitted. (9) The piston may operate the valves electrically through suitable electric contacts. (10) Valves may be provided to enable any liquid leaking past the piston to drain away. (11) Peripheral grooves may be formed around the piston to prevent leakage. (12) The relative movements of the piston and valves may be regulated by means of adjusting - devices. (13) Air-vessels or compressing-cylinders may be provided and pistons controlling the valves fitted therein. (14) Suction air-vessels may be fitted in the water-supply pipe to give a more continuous flow. (15) The combustible gases may explode beneath the piston, the water column being above.