MOTOR TRACTION

Waikato Argus, Volume XXXIII, Issue 5156, 13 November 1912, Page 3

MOTOR TRACTION

I THE THOMAS TRANSMISSION \ SYSTEM.

Seeing that motor traction is attracting Bitch a let of attention in Hamilton at the present time, a few words regarding the Thomas Transmission system may not he out of place. During the last few years the internal combustion engine has been steadily displacing the steam engine for all classes of work, from the ordinary motor car to the ocean going liner, and in older countries it is seriously challenging the steam railway locomotive both for main line and branch line passenger tralilc. The internal combustion engine has made bold and rapid incursions into every region of utility, from taxicabs to knife grinders, from fire engines to ploughs, from armoured cars to flying machines from canal barges to ocean submarines: but strange to say few have thought of connecting the internal combustion engine as we know it with express trains. Already this engine has revolutionised the various branches of road traction, and the electricially driven trarncar, which has beaten the steam train, has in turn been beaten by the internal combustion engine omnibus in the first years of its existence, and so far it Ins been found to be the only means for superseding steam for road traction.

The i,: •;! mmbustion engine has cleared olf me London streets alone nearly half a million horses, and none are putting it to better use than the railway companies, whose llaets of powerful motor lorries and omnibuses and vans are constantly being strengthened. There are many objections to the change gear system as applied to rail cars, one of which is that witu it the drive is only upon one axle, resulting either in a high maximum axle weight, with consequent increased wear and tear of the permanent way, or else a low limit to the value of the traction force that can be applied. Thus for the haulage of heavy loads very heavy rails must necessarily be used, a result which does not follow if the drive is distributed as in the Thomas system. Obviously what is wanted is a system with the advantages of the electrical system but witnout its drawbacks, such as the Mechanical System. If we compare the pure electric system with the Thomas system it is seen that there is little choice between them as regards simplicity of construction, simplicity of control, accessibility and space occupied and maintenance costs; but" the Thomas electromechanical system is free from the disadvantages of heavy weight, heavy first cost and large and continuous transmission losses. To describe the system in nontechnical terms is extremely difficult, but. broadly speaking it is a combination of an electrical with a mechanical system of transmission, whereby the power is transmitted partly electrically, but mainly mechanically. Incidentally as the electrical equipment when on top speed is not required for purposes of propulsion, it is usefully employed in automatically keeping a small battery fully charged, sn as to provide at all times an ample supply of current for lighting and for starting the engine from the driver’s seat. This battery is not essential to the transmission, but is a very useful adjunct.

Vehicles ranging from 12 horsepower to 200 horse-power have been built, and with each type record results have been obtained. The following is a certificated performu ijo of a 12-16 Dalahaye touring car fitted with Thomas transmission in a test from London to Edinburgh and back, 794 miles:—lt was loaded to 38cwt and travelled 35.73 miles per gallon of petrol, a result equivalent to 07.92 ton miles per gallon. In another 2000 miles day and night test with a Leyland lorry, also fitted with the Thomas Transmission, over a very hilly route, the ton mileage obtained per gallon of fuel was 58.04. The Thomas Transmission Company therefore hold both records, which so far have not even been approached. No adjustments whatever were made to tne Thomas Transmission equpiments during either of these trials and the result was obtained with two standard vehicles, the first of their kind ever fitted with the system. Each vehicle, before the trials, had run practically 20,000 miles and no elaborate preparations were made for the tests. For these results the Dewar Trophy was awarded by the British Automobile Club of Great Britain to the Thomas Transmission Limited “for tha most meritorious performance during 1911.” The results of rail car trials carried out in South Africa have been most satisfactory, so satisfactory in fact, that although it was ordered with no intention of being used in conjunction with a trailer, it is now intended to run it in regular service, drawing a 30-ton trailer. With the largest pure petrol electric vehicle, similar in weight and size to the Thomas Transmission car, the best result they have obtained is four miles per gallon—a very poor result in comparison with the 8.6 miles per gallon on record for the Thomas Transmission coach. In tests made with one trailer, total weight 40 tons, it was shown that on an ordinary route 5.7 miles could be covered per gallon of fuel, which is a world’s record, the ton mileage being 228. The system is equally capable of being applied to light and heavy trains, and in the latter case a distributed drive is adopted, whereby the maximum axle weight is kept low —an extremely important consideration as affecting the selection of rail section for now lines, or as regarding the possibility of increasing haulage of goods over existing light lines. In the climbing testa without a trailer, total weight 23| tons, a speed of 30 miles an hour was obtained up a gradient of one in fifty, and 24 miles an Hour up a gradient of one in forty. With a trailer, weight 40 tons, a speed of 30 miles an hour was obtained up a gradient of one in 100, while up a gradient of one in seventy 25 miles an hour was the speed test. On the level track the maximum speed obtained during the tests (without a trailer) was 50 miles per hour. With a trailer the maximum maintained speed on the level was 45 miles an hour. Without a trailer the average petrol consumption worked out at 8.5 miles per gallon, including a stoppage every 10 miles. With a trailer the petrol consumption, was 5.7 miles per gallon, including one stoppage per six miles. This represents 228 ton miles to the gallon of petrol. The best results obtained with gear driven vehicles by the Royal Automobile Club was 35.55 ton miles per gallon as against 62.98 ion miles per gallon by the Thomas Transmission vehicles.

On the test run from Pretoria to Pienaars river and return the petrol consumption was 9.2 miles to the gallon on the outward journey, and 8.1 miles per gallon on the return journey. A climb ot 1000 feet in 42 miles has to he made on this trip, the altitude of Pretoria being 4400 feet and Pienaars river 3400 feet. Motor trains are not unknown in New Zealand, where they have for some time been running on suburban lines; but so far they have been a ghastly failure and where the country was at all hilly a locomotive had to he attached to draw them. A train of this kind is about to be tried betvvecn Hamilton and Morrinsvilln, and on a fiat run like that it .might prove a success. 'i'he Thomas Transmission car, for which Messrs Thompson and Farrcr, of Hamilton, are the representatives, has been brought under the notice of the railway authorities, and in view of the statement of the Minister that he intends to prosecute ■ jght lines as feeders to the railway, 1 here should bo a good opening for , o cars in New Zealand.