Edison Electric Commercial Vehicles.
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A Description of One of the Types of Machine Fitted with Edison Accumulators. Chassis for Loads of from Half-Ton to Five-Tons Available.
Mr. Edison, as is well known, has for many years been engaged on the task of perfecting the accumulator. It may be remembered that the particular feature of that which bears his name is that the electrolyte is an alkaline substance and not an acid. The plates of the battery are nickel and iron instead of, as in the older type, lead and lead oxide. The E type cell was placed on the market some 13 or 14 years ago, to be replaced in 1908 by the present A type, for which it is claimed that not one has yet been returned owing to failure without its being proved that some maltreatment was the cause. In fact, it is stated that, although Mr. Edison has perfected a means whereby the elements of his cells may be rejuvenated, he has not yet been able to apply his method to any cell of his own construction.
Edison Accumulators, Ltd., of 2 and 3, Duke Street, London, S.W., is responsible for the sale of Edison accumulators in this country, and it is also marketing several types of battery vehicles, of which the two principal ones are known as the G.M.C. and Detroit. Both of these are fairly good examples of American construction of this class of vehicle. For the Detroit greater hill-climbing capabilities are claimed than are obtainable with the G.M.C. On the other hand, it must be admitted that the former vehicle is not quite so efficient as regards the work performed for a given current consumption.
We were enabled on a recent occasion to examine several examples of bath types and have pleasure in placing before our readers a description of the G.M.O. This is particularly interesting in view of the fact that, in the model we examined, it is adapted for use as .a nassenger-carrying vehicle.
The mechanism of the vehicles, as well as the batteries, are carried by a frame which is built up of rolled steel channels. These are sufficiently braced by suitably-placed and well-guseted cross-members. The battery is placed on top of the frame, part of it being under the driver's seat, the remainder projecting a, little way into the body of the vehicle. This is opposed to the more general method of carrying it, as it is as a rule placed in a drawer and carried below the frame. It is claimed that by putting it as the .G.M.C. people places it, it is rendered more readily accessible, besides being lifted out of the mud.
The current is taken from the battery in suitably-enclosed cables car
ried inside the channel of the main frame to the motor placed a. little behind and over the rear axle. This unit is a series-wound machine and totally enclosed. Accessibility to the commutator and brushes is obtained by means of a swinging door which can be got at from the rear of the vehicle. The drive from the motor to the bevel-driven crossshaft, carried midway along the chassis, is by means •of a special type of propeller shaft. This is a flat bar of tempered spring steel twisted so that one end is at right angles to the other. It is fitted at each end with bushed eyes, working on hardened and ground pins. Owing to the fact that one end is at right angles to the other, this shaft is to all intents and purposes, a universal joint. Its springiness has, at the same time, the same effect as a flexible coupling, and serves adequately to guard against any sudden shock coming on the gears or against there being any sudden demand for electric current owing to too rigid a connection between the power unit and road wheels.
On the ordinary type of chassis the cross-shafts are fitted on their outer ends with sprockets, which serve to accommodate the usual type of roller chain. The drive
thence is to sprockets bolted to the brake drums on the rear road wheels. For machines intended for use as passenger-carrying vehicles and also in other cases where the need for silence in operation may be more pressing chains of the sawtooth variety may be accommodated.
One of the advantages of electric vehicles is undoubtedly the simplicity of their control, one small lever above the steering wheel serving, in the vehicle under review, all the duties of controlling the motion both forward and in reverse. Two brake pedals are provided, oho of which acts on the brake drum on the propeller shaft and the other takes effect on the two drums bolted to the rear road wheels; Underneath a short bonnet in front of the vehicle are found all those parts which may from time to time require attention. For example, as our illustration shows, there are grouped here the connections for the main and lighting switches, the amp.-hour meter, and, also the control box. It is on the latter component that occasional replacements may be necessary. The fingers which make contact with the controller drum are sometimes 'fund sufficiently worn at the end Of 12 months to need replacing. Occasionally, on account of mishandling on the part of the driver, ihey may need replacing at shorter intervals. The removal of one of these fingers is the work of a moment and ,may be readily accomplished by the aid of a screwdriver.
The steering gear of the Edison electric vehicles is by means of spur wheels. The small pinion on the end of the steering column shaft engags wi.th a seCtor carried in a cas'610
ing attached to the chassis frame. The remainder of the steering gear is of the Ackermann type.
Both front and rear axles are fitted with Timken bearings, and the wheels are of the artillery type, prepared in the ordinary way for American size solid band tires. It is possible, however, for these wheels to be so altered that English sizes may be fitted if the customer so desires. The Edison Co. informs us that American experience has indicated that, in order to get the best results from the electric vehicle, a special mixture of rubber is advisable. The difference between this and the ordinary commercial-vehicle band tire is not, perhaps, very great, but owing to the fact that the mileage obtained per charge of electric current is of special importance, it has been found that greater attention must be paid to the finer points of efficient running than has been found necessary in the case of the petrol or steam-driven machine where a greater reserve of power is available under working conditions.
All sizes of these machines are available from half-ton up to fiveton, and, if the limitations of the electric vehicle as regards speed and economical daily mileage are properly realized, as well as the fact that, for certain classes of work, such as short, heavy hauls, or again, for certain varieties of town delivery work, this type of vehicle is particularly suited, then eommercial-motor users will do we 1 to consider the claims of the electric.
Following on our inspection of these chassis, we repaired to the Cadby Hall premises of J. Lyons and Co., Ltd., where we had the pleasure of a short run on a loaded two-trainer in the direction of the Crystal Palace. _ This -served principally to confirm our former impres7 sions, that, in traffic and for city work, the electric is a useful machine indeed, but that, in hilly country, its low speed on inclinee must adversely affect its utility..