THE FRENCH ELECTRIC VEHICLE TRIALS.
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Important Observations at and Deductions from the First Trials of Electric Vehicles Held in France.
DIIRING THE past few years the question of battery-driven Vehicles has often been discussed by eminent 'French engineer's and statesmen, ' and gradually a body of opinion has been -created amongst the motorcar manufacturers in favour of a revival of this type of
vehicle in Franee. " • • The plea put forward for the introduction on a. large scale of such vehicles is a commercial as well as a political onei.e., France is almost entirely dependent on overseas' ,supplies for liquid fuel, which, in consequence of adverse exchange, is not only dear, but may fail altogether in case Of war. On the other hand, the country has enormous resources of water power, and hence cheap electric current. These resources are now being rapidly developed, and it is natural that a source of energy which practically runs all to waste eiurinythe nights should be used for chargieg accumulators for the trans portation of goods and passengers on common roads. In war it has also been proved that a front can be electrified very rapidly.
In order to wake up the public attention on this vital issue and to stimulate the skill of the designers of electric vehicles and batteries, the Union des Syndicate d'Electricite (an organization composed of all the large electrical undertakings) has organized (with the .cooperation of the Automobile Club de France, the Office National des Re. cherches Indnstrielles and des Inventions and the War Ministry) a series of trials of electric vehicles.
Thesetrialstwere officially opened on Friday, September 28th, by M. Reibel, one of the French Ministers, and will be continued every day duiing the next ten days (as we now write).
A full report of theta trials will, in due course, be published by the Director of the Office National des Inventions.
The twelve vehicles taking part in the trials ere garaged in the courtyard of . the Office des Inventions at Bellevue in Meudon, near Paris, in two large tents erected for the prirpose and provided with an equal number of charging panels with all the necessary instruments, the B20
whole supplied by the Ministry of 'Inventions.
Calibrated ampere-hour meters are .fitted to all the vehicles, and every morning and afternoon they have all to Rover a well-defined route round and about Paris, in charge of drivers supplied by the manufacturers and under the supervision of official observers who take all readings and report any incident.
The charging is done at night, also under Official supervision; boosting charges are given between 12 noon and 2.30 p.m: The length of the daily circuit to be covered varies with the size of vehicle between 30 and 50 miles.
Repairs or adjustments to chassis are only allowed, between five and seven o'clock every night, but no repairs to batteries are permitted.
The routes chosen are very hard, indeed, with long and heavy gradients, and in any case end always with a long pull of 14 miles to reach Bellevue, which
happens so be situated in a very charming spot on high ground near Paris.
The trials include also three runs in Paris to test the behaviour in the crowded streets in the centre of the city end the hilly parts of Montmartre.
The vehicles engaged on these trials are as follow Six other veh'cles designed by wellknown firms had been entered, but could not be reedy in time.'
Although it would be premature after only two days to pass a well-considered
and final judgment on these' trials it would appear that they are far more than sufficient to test the hilbelimbing properties of the vehicles and not long enough to find out all about the batteries, and as the whole sties:est of the electric vehicle is solely a question of battery we fear that in the end no satisfactory conclusion will be drawn. Apart from this objection, it will give the manufacturers valuable data for future developments and settle in their mind several questions of vital importance on which they appear to differ very . much.In fact, marry designs seem to have been conceived with a total ignorance of what has been found the best practice in England and in the United States. Units such as clutches, gear. boxes—which are a, necessity, unfortunately, in petrol chassis designs owing to the shortcomings of the explosion engine—have been introduced and are, in our opinion, a source of -weakness which will cause unnecessary energy consumption lower the overall efficiency, and, incidentally, will increase appreciably the manufacturing costs. The all-important point of battery accessibility' has only received the Wen-' Lion it merlts in one or two cases.
The wiring and controllers in many cases look somewhat crude, but this may be excused as many .chassis seem to be still in the experimental stage.
Last, but not least, no standardization has been made of the charging plug. ' All types of battery are represented.. They include the best French makes, such as Tudor, T.E.1‘.11.-, Finm, Salt, and the American Edison.
The methods of driving are extremely varied, all the schools being represented, such as the two separate motor drive, thetwin motor drive and the single motor drive.
" The Krieger Vehicles.
The design of the Krieger vehicle breaks away in oearly all retpects from old-established ideas of chassis construction and certainly deserves on this account the first claim to a fuller description. The three vehicles of this make are built on similar chassis.
The inventor is M. L. Krieger, who has been well-known as an electric vehicle designer for more than 20 years.
The cbaseis frame is supported fore arid aft by a system of transverse springs, on a lower projection of the stub axles of the four wheels, which are kept in alignment by a system of short cranks articulated on the one side to the frame and on the other side to higher projections of the same stub axles. There is thus no front or hack axle.
M. Krirl.ger claims for this design the following advantages :— (1) An appreciable decrease of the total weight—the bare chassis with tyres weighs only 12 cwt. (2). A. greater elasticity of the square formed by the four points of contact of the wheels with the ground, and thus less tendenoy to leave the latter through vibration: (3) Elimination of the two axles, which are always unsprungaand are heavy and expensive parts. (4) The heaviest parts of the springs are attached to the chassis.
(5) The unsprung parts are reduced to the four wheels, stub axles and brake gear.
It is interesting to note that out of a total of 2 tons 3 cwt. the parts mentioned in (5) are barely 3 cwt.
During a test run we had with one of the vehicles ..a day or two before the official opening we were able to appreciate that., even on the roughest road, this chassis rides wonderfully smoothly and that its current consumption remains excellent. on the worst roads, which . appears to bear out the contention of the _ inventor that the minimum tractive effort is only obtainable with the minimum amount of unsprung weight.
The drive is by a single motor, compound wound, bolted to a reduction gear with differential, the whole rigidly mounted at the rear of the chassis. Two elastic joints and two floating shafts connect the back wheels to the differential gear.
The control is identical to the control of a petrol car with a speed lever, a clutch pedal and an accelerator pedal, although the functions of these apparatus are only electrical.
The speed lever is on the top of the steering column and has only three positions—neutral, forward and reverse. The clutch pedal, when coming back, releases a series rheostat, which starts the vehicle with full shunt and series excitation af the motor. When the pedal is fully released, the vehicle is capable of running at 8 to 12 miles per hour on level roads. The higher speeds, up to 20 to 25 miles per hour, are obtained by an accelerator pedal acting on a resistance in series with the shunt circuit of the motor.
When stopping or going downhill the mere release of the pedal introduces regenerative control, and either the largest part of the momentum of the vehicle is put back in the battery or the battery is being charged steadily. On a down grade of 1 in 10 the speed will be maintained at 20 miles per hour with a charging current of 60 amperes. The mechanical brakes have thus very little work to do.
The three vehicles are fitted with battery Hs follows a
(1) 42 lead cells made by the French Tudor Co. and having a capacity of 205 amp.-hours. (2) 42 lead cells of the same capacity made by the T.E.M. Co.
(3) 62 cells of the nickel-iron type made by the Salt Co., of Paris, and of 210 amp.-hour capacity.
During the first day, on a. circuit of 27 miles, including some heavy gradients, the consumption of the three chassis was found to vary between 93 and 100 watthours per ton-mile, -which should give 80 to 90 miles per charge.
The Henry Crochat Electric.
The vehicle produced by this firm is built on very orthodox lines, as can be seen from the picture. It has a capacity of six tons net load and is fitted with 120 Saft cells of 340 amp. hour capacity..
The speed on level is 9 m.p.h. and the range is'30 miles per charge: It has — a series motor driving through a differential and chains to the wheels.