A New Steam Wagon.
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One of several new steam wagons of interest is designed and manufactured by Carter's Steam Wagon Company, 13ridgefield Street, Oakenrod, Rochdale. The head of the firm, Mr. Thomas Carter, has over fifty years of engineering experience behind him, and Mr. Frank Carter, A.M.I.M.E., can boast of some eighteen years spent both in the shops and drawing office; the production may therefore be relied upon to be practical and of a reliable character. The boiler is Balmforth's patent lire-tube, constructed for a working pressure of 2oolb. per square inch, and contains 120 curved tubes lAin. external diameter, carefully expanded in the tube plates, which are conical in form. The eitect 01 making the upper tube plate conical is to completely submerge the tubes, and consequently no trouble is caused by miming out or leaking. A coil is fitted in the smoke box, and this ensures perfectly dry and slightly superheated steam reaching the engine. The grate area is 3.5 sq. ft. and heating surface 95.5 sq. ft. The boiler is fired at the top through the central tube, and a door is provided for cleaning out clinker, etc. The outer shell of the boiler is easily detached for cleaning purposes, and by simply removing the sheet iron cover (which is secured by four studs) the tubes may be swept clear of soot. The engine is a compound inverted vertical with piston valves and link motion reversing gear. It is fixed to strong cast-steel channel girders, which in turn are bolted inside the main frame, thus relieving the bolts from shearing strain. These girders are carried right across the main frame, the open side of the channel composing same being inside; they carry the crank and second motion shaft bearings. The engine is capable of developing 35b.h.p., with 20olb. of steam. An improved arrangement (consisting of two double-ported brass connections fitted with balanced piston valves) is supplied for admitting boiler steam direct to both cylinders. Every bearing is of ample dimensions to prevent undue wear or overheating, and is provided with a positive lubricator, which ensures each pin receiving its proper amount of lubricant with a minimum of attention. This method is followed as far as possible throughout the wagon, and the amplest lubrication is ensured. The righthand rear wheel is driven by the differential gear, to which it is securely bolted. The hubs of this and the two front wheels, and also the axle bearings, are made of phosphor. bronze. The frame is built up of channel steel, braced by cross-channels to carry the whole of the engine, boiler, gearing, tank, etc., without distortion. Special attention has been paid to the question of quiet and easy running without undue vibration. With this object the springs have been carefully designed, and are made in the firm's own works. The result is a wagon that rides smoothly and quietly without transmitting shocks to the gearing. The springs are the result of long and careful experiment, and confidence is felt in their success. The steering is of the Ackerman type and is irreversible. The front axle is girder section, with jaw ends machined to receive the aide arms. These latter are steel forgings ; the lever ends (for turning the road wheels) being forged solid with the arms, there is no danger of these working loose and so interfering with the action of the steering gear. Two brakes are fitted, one worked by the driver's foot, the other by a hand screw. The foot brake is powerful enough to hold the loaded wagon on most gradients, the screw brake being for emergency. The reversing gear of the engine constitutes a third brake. The tank capacity is 200 gallons and coke bunker capacity scwt., or sufficient for a day's journey. An automatic lubricator is also provided for supplying oil to the cylinders. The arrangement of engine allows of easy inspection at any time either oaded or empty. Standing, as it does, in the platform, it is continually under :he driver's eye. The drive is by means if a spur wheel on the crank shaft to
the second motion shaft, thence by spur wheel to the countershaft, and with final drive to the live axle by Hans Renold roller chain of 2iin. pitch. All the gear wheels are constantly in mesh, and three speeds of 14, 3, and 5 miles per hour are provided by means of a sliding: bush worked by a lever from the platform. The gear wheels are made from Siemens acid steel forgings, turned all over, with teeth machine cut from the solid. The differential gear is fitted to the live aide. For locking the differential gear a neat clutch is provided. The gear wheels throughout are of ample strength, being 21in. diametrical pitch (ilin. circular pitch), and the smallest pinion has 14 teeth. The boiler feed is by means of a force pump direct coupled to the crank shaft, and of ample displacement to maintain the water level under any conditions. A regulating valve is fixed on the delivery pipe so that the amount of feed to boiler can be adjusted to keep water level constant, the surplus being returned to the tank. A Gresham injector, of special type for motor wagons, is also supplied as a standby. The road wheels are 3ft. 6in. diameter rear, and 3ft. front. The left-hand rear wheel is secured to the axle by a special clutch arrangement. The collar on the axle is notched out, and the hub of the wheel is also notched out to suit. The road wheel is then forced on and secured by a fine threaded nut, which is prevented from working loose by a taper pin_ It should be noted that the crank shaft, cranks and the four eccentrics are machined from the solid forging and are correctly balanced. The link motion is case hardened and all joint pins, both in the steering gear and throughout the engine, are hardened and ground in to fit. Every wagon is tested under full load on a gradient of m in io.