The Vern Duzen Gas Engine, made by the Van Duzen Gas and Gasoline Engine Co., of Cincinnati, is shown in Fig. 5. The cylinder and water-jacket and pillow-blocks are all of one casting. The base is of one casting, and sup ports the cylinder at both ends. The governor has direct control over the gas and air valve and the speed of the engine under all conditions. It oper ates from the crank-shaft to the valve-stems by the use of gear - wheels. Should the main belt break or be thrown off, the supply of gas or gas oline and air would in stantly be reduced to such quantity as would be just sufficient to cause the engine to continue to run at the unvarying speed. The govern o• permits no air to enter the cylinder except when mixed with its proper portion of gas or gasoline. The valves are direct-acting poppet-valves. The gasoline-engine is the same as the gas-engine in every respect, with the addi tion of a carbnreter, which is attached to the air-pipe, and ex tends from the cylin der off to one side, The tank supplying the gas oline is usually placed outside the building. The enrbureter is con nected directly to, and is under the complete control of, the govern. or, and only makes the gas as it is called upon by the governor, and all the gas is consumed as it is made. The en gine is built in sizes up to 30 horse-power.
The Van Dwelt Portable Gasoline-En gine, shown in Fig. 6, is of the upright or ver tical type, but is similar in general details to the horizontal engine above described. It is mounted in a light truck. and is housed-in to protect it from the weather. The tank con taining the gasoline is braced to the roof. The engine is chiefly used for agricultural purposes.
The Naphtha -1.'ngine.—Naphtha eaglims, which utilize naphtha both as the feel under the boiler and as the Ilnid to he vaporized in the boiler and used in the engine, have recently come into somewhat. extensive employment as motors for light launches. The ad vantages for this purpose, as compared with a steam boiler• iind engine, are lightness and compactness, and the shortness of time in which the engine can be started after the lire is lighted. The naphtha lanneh-enghw made by the Gas-Engine nail Power Co., of New York, is shown in Figs. 7, 8, it, and 10. Fig. 7 is a general view of the engine in a launch, Pigs. 8 and O are respect ively longitudinal and cross sections of the engine, and Fig. 10 a sectional view of the boiler or retort. The frame is as box-shaped casting A, somewhat in the form of a trough. To the top is bolted the valve-seat and to this again the cover ii, The Main shaft is coupled to the propeller-shaft. The valve-shaft D is arranged above parallel with the main shaft. longitudinally, of the valve chest B. There are three single-acting cylinders, open at their lower ends, and closed at their upper ends, the only VI fin m indent ion from the valve-ehest to the cylinders being through the inlet port e (Pig. 8). The cranks ;Ire placed
at mingles of 12p . The valve-shaft I) has three cranks for regulating the throw of the valves. which are set a lit tle in 'Ovalle'. of the so as to give lea l to the valves. A free exhanst is thus seenred. and the pistons ire cushioned oat t 11.(11111 strokes. liall-and-soeket joints connect the pistons and rods. The pistons are elongated, having large hearing surfaces.
The slide-valves F (Fig. 8) arc each provided with two parallel upright forming a ;tilde-jaw, in which is fitted a square slide-block bored through horizontally to receive the ?orresponding crank-pin of the valve -shaft D. The in luction opening of the valve is marked f, which, when Move the port e, admits the live vapor from the valve ;hest to the cylinder. Between the lips of the valve is he ordinary arch or channel, which, when in the posi :ion shown in Fig. 8, establishes communication between he port e and the exhaust- port. An automatic naphtha is arranged at the rear end of the trough Al ibove the main shaft and in line with the row of cylin lers. At opposite sides through the valve-chest are torizontal openings, the one for a pressure-gauge, and he other for a safety-valve. A vertical channel nects the safety-valve chamber with the exhaust-chain )er and the condensing attachment. so that, when under in excess of pressure the safety-valve opens. the vapor passes direct from the valve-chest to the condenser until Rafe pressure is restored. Notion is transmitted from he main shaft to the valve-shaft by means of the gears I and I. the intermediate wheel turning on a stud Rteured to the engine-frame.
The combustion-chamber of the boiler or retort is arranged upon the valve-chest. The feed-pipe from the naphtha; pump and naphtha-tank enter its lower end. it then runs upward coiled, as shown in the figure. The ?oiled pipe is connected at its upper end by a casting with the pressure-tube O. leading to the valve-chest. Within the tube 0 is a tube P of smaller diameter. Phis tube is connected with the injector Q. A valve is provided to regulate the flow of vapor from the pipe P. The pipe finally conveys it to the burner immediately over the valve-chest, a suitable sup ply of air for combustion being drawn in-through the opening Q'. The burner itself is sim ply an annular casting held in place by being arranged to surround 0 and rest upon the nipple. The upper surface of the burner is provided at its circumference with a series of out ward holes, through which the flame is thrown against the coils and other parts of the retort for heating the naphtha and converting it into gas.