Traction engine

“ It is a fact that some men never can become good operators of a traction engine, and I can't give you the reason why any more than you can tell why one man can handle a pair of horses better than another man who has had the same advantages. And yet if you do ditch your engine a few times, don't conclude that you can never handle a traction.
If you are going to run a traction engine I would advise you to use your best efforts to become an expert at it. For the expert will hook up to his load and get out of the neighborhood while the awkward fellow is getting his engine around ready to hook up. ”

“ In general, in the traction engine, look to the convenience of arrangement of the throttle, reverse lever, steering wheel, friction clutch, independent pump and injector, all of which should be within easy reach of the footboard, as such an arrangement will save annoyance and often damage when quick action is required. ”

“ The gearing by which the traction wheels of a traction engine are made to drive the engine is an important item. Of course, it is desirable to apply the power of the engine to both traction wheels; yet if both hind wheels were geared stiff, the engine could not turn from a straight line, since in turning one wheel must move faster than the other. The differential or compensating gear is a device to leave both wheels free to move one ahead of the other if occasion requires. ”

“ Traction Farm Engines are becoming more generally used each year, and to supply the increasing demand for traction engines, the manufacturers have spared no expense or mechanical skill to place upon the market the latest improvements in this line, and a great many kinds of this class of engine now made in the United States are simply perfect. They travel over the roughest roads, up and down steep hills with heavy loads, and the engine is at all times entirely under the control of the engineer. ”

“ The throttling engine regulates the speed of the engine by cutting off the supply of steam from the boiler, either by the hand of the engineer on the throttle or by a governor working a special throttling governor valve. Railroad locomotives are throttling engines, and moreover they have no governor, the speed being regulated by the engineer at the throttle valve. Traction engines are usually throttling engines provided with a governor. ”

“ The gearing of an engine should never be run without first greasing them thoroughly with a good quality of solid oil or axle grease, for if once you allow the teeth to cut, it will be impossible to stop them from cutting, the result being they will soon be ruined. The gearing on traction engines are placed in many different positions for transmitting the power to the traction wheels, as will be seen by examining the different illustrations given in this book. ”

“ The double cylinder and cross compound style have been very successfully adapted to traction engine purposes with certain advantages that no other style of traction engine has. With two cylinders and two pistons placed side by side, with crank pins at right angles on the shaft, there can be no dead centers, at which an engine will be completely stuck. Then sudden starting is liable to throw off the main belt. With a double cylinder engine the starting is always gradual and easy, and never fails. ”

“ In the road traction-engine the need for what may be termed effort on the part of the mechanism is much greater, more especially as the competition against horse-traction is conducted on terms so much more nearly level. A team of strong draught-horses driven by one man on a well-loaded waggon is a far more economical installation of power than a two-horse buggy carrying one or two passengers. ”

“ The traction wheels are of the cast iron rim style, with wrought iron spokes cast in both rim and hub and mud cleats are cast on rim. The foot board is furnished with a water tank and tool box and all necessary fittings and attachments are supplied to make a complete traction engine. ”

“ While talking of the various appliances for oiling your engine you will pardon me if I say that I think every traction engine ought to be supplied with an oil pump as you will find it very convenient for a traction engine especially on the road. For instance, should the engine prime to any great extent your cylinder will require more oil for a few minutes than your sight feed will supply, and here is where, your little pump will help you out. Either the Detroit or Powell people make as good an article of this kind as you can find anywhere, and can furnish you either the glass or metal body. ”

“ Some automatic cut-off gear is almost always used. A high speed engine may attain 900 revolutions per minute, 600 being common. In many ways it is economical.
CONDENSING AND NON-CONDENSING.
In the traction engine the exhaust is used in the smokestack to help the draft, since the smokestack must necessarily be short. A stationary engine is usually provided with a boiler set in brickwork, and a furnace with a high chimney, which creates all the draft needed. In other words, the heated gases wasted in a traction engine are utilized to make the draft. ”

“ A traction engine was required for the transport of sugar-canes in Java. Thomson recurred to his old idea of india-rubber tyres, and found a solution of the difficulty in designing a traction engine. The tyres were not fastened to the wheels, but adhered to them by friction. They formed a broad pad or elephant's foot, by which the great weight of the engine was distributed over a large surface. The outer surface adapted itself to every peculiarity of the ground, and the inner surface formed a constant endless platform on which the comparatively rigid engine worked. ”

“ Several attempts have been made to connect the leading wheels of a traction engine with the driving wheels, so as to make drivers of all of them, and thus increase the tractive power of the engine, and to afford greater facilities for getting along soft ground or out of holes. ”

“ With steam-power, the gain by careful grading and excellence of construction of the road-bed becomes still more important. The animal mechanism is less affected in its power of drawing heavy loads than is the machine. With the horse, a bad road impedes transportation principally by resisting the movement of the load rather than of the animal, while with the traction-engine the motor is as seriously retarded as the train which follows it, and frequently much more, on soft ground. ”

“ When fresh country is opened up, years must often pass before a proper high road can be made, yet there is great need of an organised system of transport. Whither ordinary traction-engines, or carts, even horses, could scarcely penetrate, the pedrail tractor, thanks to its big, flat feet, which give it, as someone has remarked, the appearance of "a cross between a traction-engine and an elephant," will be able to push its way at the forefront of advancing civilisation. ”

“ On a small scale, and with but little success, gas traction has been recently tried. There is a difficulty in starting the engines, therefore they have to work continuously, which causes the unpleasant noise familiarised to us by petrol-driven motor-cars when standing still. There is a decided smell from the “exhaust” of the engine; the vibration is considerable; and, as at present designed, the cars cannot mount a moderately steep hill.
Steam traction has been in use for some time, but has not improved, and is not popular. ”

“ They have a traction engine with considerable modifications in its design, with which they, expect to run from Paris and Marseilles, and they have the intention of hauling with it one of the 40-seat omnibuses of the Paris Company, which is usually drawn by three horses. Fig. 10 is a general view of the engine attached to the omnibus. This type of vehicle is furnished with a compound engine, which can be worked up to 30 horse power, and which is to be capable of hauling a load of 5 tons at a speed of 12.5 miles ”

“ Whether Starley actually invented the device or adapted it from Aveling and Porter’s road traction engine is obscure; in any case he should have the credit of being the first to recognize its importance. ”

“ It must be learned by experience. Good judgment is required to make a success of it. One man should always handle both reverse lever and steering wheel when guiding an engine.
Q. How should the steering chains be put on a traction engine?
A. The chains should be so put on, that when the steering wheel is turned to the right, the engine turns to the right; when wheel is turned to the left, the engine turns to the left.
REVERSING AN ENGINE.
To reverse the motion of a plain Slide Valve engine, remove the cover of steam chest and place the engine on the dead center. ”

“ It is claimed, moreover, that the additional traction power and superior ease of carriage on rough roads, secured with rubber tires, is dearly bought at the very great increase in cost, of an engine fitted with them, over one not so fitted. ”

“ Tractive force is the power which the pistons of the engine are capable of exerting through the driving-wheels, to move the engine and train. The efficiency of the engine’s traction is dependent upon the adhesion of the wheels to the rails; for, where the adhesion is insufficient, the pistons will slip the wheels, and no347 useful effect will result. To prevent the wheels of ordinary American engines from slipping on dry rails, the weight resting on the drivers must be about five times the power exerted by the pistons to slip the wheels. ”

“ So far as cycles and motor-cars are concerned, this is the best solution of the problem of averaging the inequalities of a road that has yet been presented; but when we come to consider the making of provision for goods traffic carried by traction engines along ordinary roadways, the difficulties which present themselves militating against the adoption of the pneumatic principle—at any rate so long as a cheap substitute for india-rubber is undiscovered—are practically insurmountable. ”

“ On electric cars the motor is generally suspended from the wheel truck, and a small pinion on the armature shaft gears with a large pinion on a wheel axle. One great advantage of electric traction is that every vehicle of a train can carry its own motor, so that the whole weight of the train may be used to get a grip on the rails when starting. Where a single steam locomotive is used, the adhesion of its driving-wheels only is available for overcoming the inertia of the load ”

“ To start in half the time, double the force must be exerted. For this reason, trains which start and stop often require engines with a great deal of weight on the driving-wheels. In accordance with these conditions a class of engines has been designed which carry all, or nearly all, the weight of the boiler and machinery, and sometimes the [125] water and fuel, on the driving-wheels. For suburban traffic, the speed between stops must often be quite rapid, and consequently the engine must have a long wheel-base for steadiness, as well as considerable weight on the wheels for adhesion. ”

“ By changing from one pair of gears to another, the driven shaft, and, consequently, the wheels, may be run at a greater or less number of revolutions, while the speed of the engine and the driving shaft do not change. The number of power strokes that occur during one revolution of the wheels is thus changed, and they turn with more force or with less.
High speed, or high gear, means the combination of gears that gives the greatest speed to the wheels, but the fewest power strokes to each revolution. ”

“ Standing on the platform at King’s Cross, with a large part of the immense driving-wheel hidden below you as it rests on the rail, you do not realise its tremendous size. Yet, let the engine-driver open the throttle, as it is called—that is, turn on the steam to the cylinders—and that huge wheel will revolve, and with its neighbour on the other side, haul after them that heavy train of carriages, and, gathering speed as they go, they will soon be rushing up the incline at forty miles an hour, and then on at sixty. ”

“ Fig. 42. Progressive Transmission. Low.
Economy of Transmission Gearing.—From an economical standpoint, also, it would be undesirable, even though the engine should be able to make the speed.
Owing to the explosion impulses of the gasoline motor, a heavy fly wheel is necessary on the engine shaft, in order to store up power by momentum, and also to give a uniform speed.
In hill climbing, or in carrying heavy loads, (71) the transmission shaft must have its speed cut down, while permitting the engine to run at full or normal speed. ”

“ This refers, of course, to the clutch, brake, and throttle pedals. In cities, running through crowded streets, the foot throttle should be used, so as to keep both hands free; but in the open country, where change is not required so frequently, this control is usually by hand.
The Crucial Point.—The crucial point of every learner, is starting the machine. The first duty is to note that the transmission lever is at the neutral point, and that the emergency brake is set. The spark control lever is then set at the proper point, and the engine cranked, if it has no self starting mechanism. ”

“ For a decade—up to 1890—all kinds of improved methods of haulage were tried: compressed air, coiled springs, underground cables (a well-known example of which was the Highgate line, which was always breaking down) , and, lastly, gas traction and steam traction.
To all these methods there are serious objections. Horse traction is expensive, besides being distressingly trying to the animals themselves. It is necessary to keep up a large stud for each car, and the horses when idle are eating their heads off. Their fullest speed with the heavy cars is necessarily low. ”