SOME UNCONVENTIONAL ENGINES.
Page 32
If you've noticed an error in this article please click here to report it so we can fix it.
A Résumé of Recently Published Patents.
-The ERHAPS the most interesting part
of specification No. 205,842, by L. A. Noel, is the description of the working cycle of the engine, the design of which is the subject of the patent. It may best be referred to as a two-stroke five-phase motor. Commencing with the explosion, the cycle of operations is as follows :— (1)A short. expansion period, terminating about, two-thirds stroke. (2) A very brief exhaust period, occupying only three or four degrees of the crank rotation. (3) The creation of a partial vacuum within the cylinder. (It should be noted that these three operations are concluded in the one downward stroke of the piston.) The next operation, No. 4, occurs while the crank pin is on the bottom dead centre, when the inlet ports are opened, and the combustible mixture rushes in. (5) is compression, which occupies the whole of the upward stroke of the piston, ignition taking place spontaneously. The peculiar distribution of the gases is effected by means of a sleeve valve, working in conjunction with the piston, the wall of which is extended upwards beyond the head, and is there ported so as to be capable of acting as a seCond sleeve. For the passage of gas either in or out of the cylinder it is necessary for three ports to come into line : one in the piston, one in the sleeve valve, and one in the cylinder wall. For the exhaust, piston and sleeve valve are travelling in opposite directions, the former moving down, the latter travelling up, hence the brief duration of the exhaust period. Daring induction these components are at the ends of their respeotive strokes, " dwelling," at their opposite dead centres, so that there is ample time for the inrush of the mixture.
As a result of te short time allowed for the escape of the exhaust gases, the cylinder is not completely emptied of them. Some remain, to mingle with, and dilute, the new gases.
For starting purposes, in the case of fuels which might not ignite when the engine is cold, an igniter is provided.
Other Patents of Interest.
'Another novel rower unit, is the subjecti of specification No. 206,057, the patentee being G. Fornaca. It is closely related, in the principles of its operation, to a hot-bulb engine, differing from the general run of them in that its system of ignition incorporates the familiar sparking plug, and in that it embodies provision for ready starting from cold, making use of more volatile spirits for that purpose, and subsequently consuming such fuels as na,phtha and heevy oils of various types.
The fuel arrangements embody, on the one hand, a carburetter for petrol, and, on the other, a pump for the heavy oil, delivering its fuel past a cut-off valve to a spraying valve. The same inlet valve does for both fuels, and the operating gear is devised to open the spraying valve in time with the induction valveThe combustion chamber embodies an inverted bulb, which ia disposed immediately underneath the spraying valve.
For starting purposes there is a threeB48
way valve which, in one position, opens communication from the carburetter to the cylinder, enabling it to take in an explosive mixture of petrol and air in the ordinary way. In the other position pure air enters the cylinder by the same passage as that along which . the petrol mixture travels. The lever which controls this three-way valve is _also. connected to the heavy fuel cut-off valve, closing it when the carburetter is in communication with the cylinder and opening it when thati communication is severed.
Alter working with' spirit for a few minutes the control lever is moved over to allow of the heavy fuel being used ; the cut-off valve is opened and oil allowed to pass to the spraying valve, which has, in the meantime, been opening and closing quite innocuously. Air passes in with the oil and vaporizes it, the operation being completed when the oil strikes the hot bulb. Ignition is .effected by a sparking plug, the bulb• never being allowed to become sufficiently hot to cause spontaneous combustion.
The hydraulic tipping gear which is described by S. E. Alley and another, both of the Sentinel Waggon Works, Ltd., provides for multi-way tipping without necessitating any oscillation of the hydraulic cylinder. The latter is rigidly mounted on the frame of the chassis and its piston is linked to the body by a coupling rod, which is universally jointed at each end. Another feature of the invention is in the arrangement of the connection between the cylinder and piston and the tipping part of the vehicle, the former being considerably below the centre of gravity of the loaded body.
The Watson six-wheeled tractor-trailer combination has already been described at some length in our general news pages. The technical details of the invention are now disclosed in patent specification No. 205,911, by G. W. Wateon and W. IL Hingston. Its outstanding features are the three-point suspension of the body upon the tractor and trailer and the ingenious method of coupling the tractor and trailer.
In a former patent specification, No. 117,7771 H. M. Butler, of Kirkstall Forge, described a. construction of double-banjo axle, formed in one piece, of forged steel, with the lower cover or grease-retaining reservoir. In the present one, No. 205,975, the same idea is embodied in an axle which is designed for use in connection with electric vehicles in which two motors are employed—one for each wheel. The axle is a double banjo, with two enlargements—one for each reduction gear from the motors.
Specification No. 206,079, by F. H. Royce, deals with the means of controlling the proportions of exhaust gas which are passed to the carburetter jacket. The design provides independent means of closure for the valve in the exhaust pipe' which opens in conjunction with the throttle valve, and any sticking of the former cannot prevent closure of the latter.
Means of interconnection for the ignition and throttle controls and a governor are described in specification No. 205,844, by J. L. Brunton and another. The ignition and throttle levers are connected together and to the governor mechanism by a Bowden-type wire.
For his ratchet gear D. S. de Lavaud proposes to use halls or rollers, the surfaces of which are not truly spherical or cylindrical. They are so mounted in races that, for motion in one direction, they jam, freeing themselves when that motion is reversed.