Fig. 32.—Capitaine Gas Engine.
Fig. 33.—Horizontal “Balance” Motor (Capitaine).
This third engine has a vaporizer which is in permanent communication with the cylinder, and is so constructed that even if it became red-hot there would be no risk of pre-ignition or the formation of tarry oils which would foul the cylinder. The vaporizer only draws in sufficient petroleum at a time for one explosion, and then only during the aspirating stroke of the piston. At the end of this stroke the whole of the petroleum in the vaporizer is gasified. The first motor on this plan was built by Capitaine in 1889, and many of them are still constructed at the present date by M. Louis Herlicq of Paris.
Fig. 34.—Capitaine Two-cylinder Gas Engine.
Capitaine came to an agreement with Grob et Cie. in order to exploit his inventions in a wider field. Unfortunately differences arose, and in 1891 the agreement was cancelled. A lawsuit followed, lasting till March 26, 1893, when it was brought to an end by Grob et Cie. agreeing to pay Capitaine the sum of 125,000 francs in consideration for permission to use his name and patents in connection with their motors. After breaking up the partnership with Grob et Cie., Capitaine continued to build engines, and has since then taken out several patents, which have considerably enhanced the value of his previous inventions. In the 1892–93 type a lamp is used for starting which can afterwards be dispensed with, the heat of the compression being sufficient to maintain the temperature of the vaporizer. This is, however, only if the motor is developing more than three-quarters of its full power. When it was found that the same shaped indicator diagram could be obtained from these motors even when they were giving only 75% of their full power, it became obvious that it was only necessary to keep the vaporizer as warm as possible by covering it with non-conducting jackets, in order to get the engine to run at quite a small fraction of its full power. Capitaine has, by carefully observing this condition, obtained a motor which will run at all loads without any external heating apparatus.
The vaporizer forms part of the combustion chamber, and is carefully covered with non-conducting material. Only hot gases are allowed to pass through it. It must be started by heating for a few minutes with a small hand-lamp, and the engine is then ready for work.
Merlin motor.—This motor is of the vertical type, and resembles the Capitaine motor in some respects. The oil is stored in a reservoir in the bed-plate; this receptacle is in communication with an air-pump driven by the motor, and also with an oil-pump. The pressure of air generated by the former forces the petroleum up into the oil-pump, which in its turn passes it drop by drop through a pulverizer, after which the spray of oil enters a vaporizer and becomes gasified. The vaporizer is heated by a special petroleum lamp. Ignition takes place when the explosive mixture comes into contact with the heated walls of the vaporizer, their temperature being always high enough to ensure ignition taking place. The consumption of fuel is regulated by a governor acting on the oil-pump, preventing it from supplying more oil than is absolutely necessary to keep up the speed. The governor regulates the exhaust valve as well, so that the speed, which is pretty high, is kept quite constant.