All cylinders drive on one crank-axle with three cranks at 120°.
The pulley E is driven from an axle of the carriage.
There are two soft iron tongues, n, s, fixed upon and at right angles to an axle a, which works on pivots at its ends.
The advantages claimed for it are: short coupling-rods, large and unlimited fire-box carried by a trailing axle, compactness, and great power for a given weight.
This is done by the little crank B on the axle of the fly-wheel, acting through the rod C, and the bent lever D, which forms a toggle-joint at E with the vertical piece of metal below it.
When portable cranes are fitted with springs and axle-boxes, drawgear and buffers, so that they can be coupled to an ordinary railway train, they are called " breakdown " or " wrecking " cranes.
The horsepower available at the driving-axle, conveniently called the brake horse-power, is from 20 to 30% less than the indicated horse-power, and the ratio, B.H.P./I.H.P. =E, is called the mechanical efficiency of the steam engine.
(4) " Four-coupled " three-axle type, with trailing axle, 0-4-2.
16, which shows in a diagrammatic form a wheel and axle connected to the framework of a vehicle, in the way adopted for railway trains.
In the second case every axle in the train may be made a driving-axle if desired, in which case the locomotive as a separate machine disappears.
The power is applied by steam acting directly on a crank at one end of the axle, and the diameter of the fan may be 40 ft.
The gear operating the paper roll is driven from the axle of an inde pendent wheel which is let down into contact with the rail when required This wheel serves also to measure the distance travelled.
This would be distributed between three coupled axles giving an average of 1.38 tons per axle, though the distribution might not in practice be uniform, a larger proportion of the weight falling on the driving-axle.
The siphon is supported on a vertical axle carrying two armatures which are acted upon by two electromagnets.
An axle carrying four cams is normally at rest, but it is thrown into gear with the mechanism when the armature rises, makes one complete revolution, and comes to rest ready for the next signal.
The weight W 1 carried by the part of the frame supported by the wheel (whose diameter is D) is transmitted first to the pins P 1, P2, which are fixed to the frame, and then to the spring links L 1, L2, which are jointed at their respective ends to the spring S, the centre of which rests on the axle-box.
Let a couple be applied to the axle tending to turn it in the direction shown by the arrow.
Assuming the wheels to roll along the rail without slipping, this couple will be equivalent to the couple formed by the equal opposite and parallel forces, F 1 acting in the direction shown, from the axle-box on to the frame, and F 1 =µ0, acting along the rail.
If the speed is given in miles per hour, S say, V =1.466 S (6) The revolutions of the axle per second, n, are connected with the radians turned through per second by the relation n =w/27r = w/6.38 (7) § 2.
Motors may be applied to every axle in the train, and their individual torques adjusted to values suitable to the weights naturally carried by the several axles.
Occasionally a somewhat similar type is designed with the bogie under the fire-box and a single leading axle forward under the smoke-box - an arrangement in favour for suburban tank engines.
(io) " Eight-coupled " type, with a leading axle, 2-8-0.
Occasionally the American eight-coupled type has a bogie instead of a single leading axle (4-8-0), and is then termed a " Twelve-wheeler," or " Mastodon."
It is used to a limited extent for mountain-grade goods traffic, and has the advantage over the " Consolidation " or eight-coupled type of lighter axle loads for a given tractive capacity.
In both the four-wheeled and the six-wheeled types the axles were free to rise and fall on springs through a limited range, but not to turn with respect to the body of the carriage, though the middle axle of the six-wheeled coach was allowed a certain amount of lateral play.
Gauge, and laid with rails weighing from 50 to 70 lb per yard; a flat-footed 60 lb rail, with the axle load limited to 14 tons, has the advantage for such lines that it permits the employment of a proportion of the locomotives used on main lines.
0.5 in.); weight of rails, 12 (26.45 lb) to 20 (44 lb) kilos; mean load per axle, 6 tons; minimum curve, 70 m.
36 gives the loads per axle and the distribution of loads in some exceptionally heavy modern British locomotives.
Corn is threshed by a norag, a machine resembling a chair, which moves on small iron wheels or thin circular plates fixed to axle-trees, and is drawn in a circle by oxen.
The couple T is necessarily accompanied by an equal and opposite couple acting on the frame, which couple endeavours to turn the frame in the opposite direction to that in which the axle rotates.
7 he torque exerted on the driving-axle by the steam engine just at starting may be that due to the full boiler pressure acting in the cylinders, but usually the weight on the coupled wheels is hardly sufficient to enable advantage to be taken of the full boiler pressure, and it has to be throttled down by the regulator to prevent slipping.
The motion of the rod consequent to a motion of the case is modified by the projecting axle of the stationary mass, and after much magnification is recorded on a sheet of smoked paper.
Diamonds are now employed not only for faceting precious stones, but also for cutting and drilling glass, porcelain, &c,; for fine engraving such as scales; in dentistry for drilling; as a turning tool for electric-light carbons, hard rubber, &c.; and occasionally for finishing accurate turning work such as the axle of a transit instrument.
With rows of coarser straight teeth, each row set parallel with the axle of the machine.
When the agreed-on weight is on the drum, the silk is drawn across the face of the drum parallel with its axle, and pulled off in form of a sheet, and is called a lap. This lap is thin, but presents the fibres of silk now joined and overlapped in a continuous form, the length measured by the circumference of the drum.
Apart from this general meaning of the word, the chief transferred use is that for a piece of wood used for various specific purposes, as a framework, bar, &c., such as the tree of a saddle, axle-tree, cross-tree, &c.
By numerous guide blades, dividing it up into a series of rectangular tubes of diminishing section, attached to a horizontal axle by cast iron bosses and wrought iron arms. The tubes at their smallest part are connected to a cast iron ring, io ft.
The low-pressure cylinders drive on the leading crank-axle with cranks at right angles, the highpressure cylinders driving on the trailing wheels.
(3) " Four-coupled " three-axle type, 2-4-0.
Engines of this class, with 78-inch driving wheels and the leading axle fitted with Webb's radial axle-box, for many years did excellent work on the London & North-Western railway.
(5) " Four-coupled " type, with a leading bogie truck and a trailing axle, 4-4-2.
(8) " Six-coupled " type, with a leading axle, 2-6-0.