The Works Of Messrs. Schneider And Co.

ELECTRO-CHEMIOAL AND METALLURGICAL DYNAMOS. 123 part of the regulating device, and is mounted on a separate shaft ; the range of steam admission varies from zéro to half-stroke. The following are the leading dimensions of these engines : Diameter of high-pressure cylinder .550 ni. 21.653 in. „ low-pressure cylinder ... Length of stroke .850 m. 33.464 in. .900 m. 35.433 in. Number of revolutions 125 125 Initial pressure on small piston 8 to 9 kg. 113.8 to 128 Ib. per sq. in. Indicated horse-power 700 700 The whole of the machinery connectée! with this large installation was furnished by Messrs. Schneider and Co. Electro-Chemistry and Electro-Metallurgy Dynamos. —Important industries have been developed of late years in the production by electrolysis of soda, chlorate of potash, means of arms cast on them, the cast-iron socket which acts as a nave for the commutator, this being driven by a disc keyed on the sliaft. Rolled-out cables constitute the armature conductors ; they are connected by means of strips, protected against the effeets of centrifugal force by a coupling circle in two parts. The coils are fixed by a certain number of steel wire hoops, which press the conductors on the smooth surface of the ring. Carbon brushes, 72 in number, are mounted on eight insulated copper rods, fixed on a cast-iron circular plate, worked by screw gearing carried by the bearing block on the commutator side. The bushes are lubricated automatically ; the level of the oil in the boxes can be ascertained at any moment. The dynamo is, when possible, worked by turbine, by means of a Raffard coupling-box. Its speed is 240 revolu- Fig. 352. Eight-Pole Contimious-Current Dynamo. aluminium, and Carbide of calcium. Appended are notices of several types of dynamos manufacturée! by Messrs. Schneider and Co. for such industries. 8oo Horse Power Dynamos.—Octagonal 800 horse- power, self-exciting, 700-volt dynamos, on the Thury system, for the manufacture of chlorate of potash, have recently been built at Creusot. Each dynamo consista of a magnetic shell, formed of eight electro-magnet cores supporting the inductor coils and eight branches bolted on the magnets. Two lifting rings facilitate the handling of this arrangement ; it rests on a cast-iron frame with the interposition of cast-iron supports, gun-metal wedges and mica sheets, which insure the magnetic and electric insula- tion of the mass. This machine is illustrated by Figs. 350 to 352. The armature is drum-wound ; it consists of a laminated smooth ring, mounted on connected regiets of a cast-iron studded nave keyed on the shaft. The regiets carry, by tions, and it does not spark when under füll load. This type has invariably given most complété satisfaction. Self-Exciting 450 Horse Power Dynamo.—This is also of the Thury type, but is a 12-pole machine (see Figs. 353 and 354, and Fig. 355, Plate LXXX.) ; a number of these dynamos have been manufactured at Creusot. The niethod of construction of the inductor and armature and the winding are practically similar to those of the machines just described. As this type, however, gives 100 volts and 3,000 amperes in füll load, the commutator is made wide and small in diameter, comparée! with that of the armature. It has been found necessary, in con- séquence, to place a hoop in the middle of the commutator, to prevent deformations which might otherwise arise in erecting, during the tightening of the segments. The carbon-holder rods are connected to a cast-iron circular plate, guided by six gun-metal supports, maintained by screws on the shell. The displacement of the brushes 2 B