GAS-PRODUCERS AT THE PARIS SALON.
Page 14
Page 15
If you've noticed an error in this article please click here to report it so we can fix it.
Detail Improvements in the Mechanism Making for Longer Runs per Fuel-charge, Easier Starting, Greater Engine Efficiency and Wider Choice of Fuel.
NOT quite so many gas-producers were to be found in the Paris Salonthis year as at the last Show. but this does not mean that there is any wane in the activity of the French manufacturers. It is true that one or two of the smaller producer-building concerns have come to grief through starting with inadequate capital, but the remaining firms are all doing good business. Their trade, however, being almost entirely a Colonial one, some of the firms do not consider that the expense of exhibiting in Paris is justified.
The chief improvements in the machines shown are to be
found in the gas-filtrations arrangements. In the latest Sagam machine, the final cleansing of the as before it reaches the engine is effected by a patented filter consisting of a lottg, hexagonal wire frani-e closely, wound with cotton. One advantage of this filter is the fact that whilst it stops the smallest particles of duet or grit, the moisture content of the gas is able to pass through. Cleaning the filter only necessitates a few seconds' work, as the wire frame can be drawn out comPlete, shaken and replaced ; ail operation which should be performed at the end of each day's run.
A Generator to Burn Wood Fuel or Lignite.
The Sagam generator is now arranged for the use of wood fuel or lignite. In arranging their machine for the latter fuel, the constructors are making a bid for the home market as well as the colonies, for lignite, the German "brown coal," is exceptionally cheap in France at the moment, owing to the enormous quantities handed over under reparation arrangements. Actually, the fuel may be obtained at about 200 francs per ton almost anywhere throughout the country and, even when the German supplies run out, certain important lignite beds in the Landes, now on the point of being exploited, should 'ensure the maintenance of a low price level.
Drown coal is naturally a less bulky fuel than wood, For Instance, the hopper on the Sagam will contain sufficient wood'for a run of 2i hours with a medium-powered lorry, but enough. brovin coal for a 3i-hour run. The generator is cylindrical in form and the central portion is pierced with a double row of air intakes, which hasten the combustion of the fuel and ensure its distillation.
The gas produced, still carryine-' a proportion of tar, Is sucked by the engine through the lower part of the furnace. The latter, which is in special cast iron, contains tar-retaining material and the gas in passing through the latter raises its temperature to a very high point, thus allowing tar and other pyroligneous products to be separated entirely from the gas.
The cleaning unit comprises a scrubber fitted with steel turnings, a condenser consisting of large-diameter pipes fitted with spiral baffles and patented water ejectors, and the Special filter already rescribed.
A Simplified Gas-purification System.
G.E.P.E.A. the oldest French gas-producer firm, have greatly simplified their gas purification system, and rendered that portion of the machine very 'neat and compact. The arrangement comprises a cylindrical box containing a mixture of broken coke and sawdust, through Which the gas is passed. After lengthy experiments with other .forms of cleanser, the makers have found this simple appliance to give the best results 'with their particular form of generator, which uses charcoal fuel only. The coke mixture is carried in a quickly removable retainer, which should be taken out and washed after 300 railed, a spare retainer being carried on the lorry. The usual systeth Of cross tubes is employed for cooling the gas, and the generator itself is of the "reversed combustion" type, in 'which the elimination of dust and tarring matter takes place to a very great extent in the furnace itself.
A good feature of the G,E.P.E.A. outfit is the ease, with which it can be mounted on any standard lorry chassis, only eight bolts being required to maintain the whole apparatus
in position. , A novel feature of the Panhard-LevaSSor machine this year is the fitting of an electric motor to the starter fan, the motor being mounted directly on the fan shaft. This is a .particularly useful fittitg, which should reduce the expenditure of time and labour when starting up in the morning, the fan, moveover, being brought into operation by the driver without leaving his seat.
A Novel Feature of the Panhard Generator.
The Panhard generator is of large capacity, and when in regular use the fire can be kept in at night, so that a brief use of the fan is all that is needed to get going again in the morning. The gas-cleaning arrangements are unchanged. They comprise a cleaning chamber filled with broken coke, and a capilliary filter in which the gas passes through a great number of tubes of small diameter mounted vertically.
In the Renault machine, a new cotton filter has been introduced consisting of a number of small cotton bobbins, through which the gas passes for its final cleansing before entering the engine. The Renault generator is an appliance of normal design employing charcoal either in natural or compressed form as fuel.
Dewald, who adopted the Autogaz machine some time ago, now turns out a gas-driven lorry in which the engine is specially designed for the use of producer-gas, extremely large valves and a high-compression ratio being features of the Dewald engine. Compressed air is employed for starting Purposes. An air pump is mounted on the near side of the crankcase and driven off the camshaft, whilst the stora,V cylinder is carried on a side member of the frame.
Charcoal Fuel Used in the Autogaz.
The Autogaz employs charcoal fuel in a horizontal furnace, and the gas purification includes four separate processes ; bubbling through water, mechanical filtering, bubbling through oil, and finally, a second mechanical filtration. In spite of this very thorough treatment for the gas, the whole of the cleaning apparatus is arranged in a comparatively small box. The hand-operated starting fan is placed within easy reach of the driver, so that he can operate it without leaving his seat. This obviates the necessity for switching over to petrol when restarting after a prolonged stop.
A point worth noting in connection with the French gas machines shown is the fact that several makers have had excellent English catalogues printed this year.
In connection with the use of brown coal in gas-producers for automobile work, it is worthy of note that the gas-driven Aries lorry with Sagam generator, which won the Theodor Cup, used 538 kilogs. of lignite blocks for the 614 kiloms. As the lorry carried a full load of 5 tons, the total weight of the vehicle was 9,520 kilogs. At the market price of brown coal in France, this performance represents a fuel cost of .018 franc per ton-kilom. That is to say, .0364.