The elevators used in the Eiffel Tower are arranged in the following manner: Two elevators on the Roux, Combalnzier, and Lepape system, with chains of jointed rods, lift from the ground to the first platform, working alongside the staircases in the east and west piers. Two elevators on the Otis plan work in the north and south piers, starting likewise from the ground and ris ing to the second platform at 380 ft. height, with option of stopping at the first plat form. Lastly, by an elevator on the Edoux system, placed vertically in the center of the tower, visitors are raised from the sec ond platform to the third at a height of 006 ft, above the ground.
The Ronx elevator follows a curved path, and therefore the otherwise rigid actuating piston is replaced by a jointed one, which may be compared to a vertebral column. It is, in fact, composed of a series of links having the form of connecting rods, attached to each other by knuckle-joints. These links are, besides, furnished with two guiding friction-rollers at each point of attachment.
The link, thus articulated, is in troduced into a round or square guide-way, in which it runs easi ly, and follows all sinuosities as well as if it were a chain worked by traction. By fixing a link of this chain to the floor of an or dinary elevator-cage, and impel Eng the flexible chain by means of a suitable wheel, driven by any motive-power whatever situ ated at the bottom of the eleva tor, it is easy to see that the chain will follow the cage wher ever its guides will permit it to run. By joining the two ex tremities of the flexible chain, it forms an endless chain of rods moving over two encaged wheels. The lower wheel applies the power, and the upper one acts as a simple pulley-wheel to ena ble the chain to circulate.
The Otis elevator is of the hydraulic type described else where, the power being derived from a hydraulic cylinder 36 ft. long, having a 38-in. piston with two 4f-in. rods, the upper ends of which are fastened to a truck V carrying six grooved pulleys 5 ft. in diameter. The hydraulic cylinder is single-acting. water being admitted to the top only. The cabin, truck, and safety appliances make up a weight of 23,000 The Edoux elevator has a pair of cabins working vertically and balancing one another.
The hydraulic cylinder is verti cal, and about 2:10 ft. long. The upper cabin is carried on two hydraulic rams.
For full details of the Eiffel Tower elevators see Proc. Inst. of Mech. Eag., July 2, 1559.
Electric Elerator.—The elec tric elevator, as made by Otis Brothers & Co., -imply consists in the application of an electric motor to the hoisting-gear of the apparatus. The motor is so
arranged as to start and stop with a gradual movement, and to consume power only in pro portion to the load. The con struction is clearly shown in Fig. 10.
III. OaAtx ELEVATORS.— The elevator known as elevators A and It, belonging, to the Armour Elevator Co.. of Chicago, I11., and receiving grain from the St. Paul road, is the largest elevator in the world under a single roof. Elevator D and its annex, belonging to the Armour Company, surpass it in capacity, but are not a single, unbroken structure. It is rated at a storage capacity of 2,500,000 bushels, can unload 500 cars per day, and deliver 100.000 bushels per hour to cars and boats. Cars enough to keep it at work for four days can be accommodated in the great yard annexed to it. The building proper is 550 ft. long and 156 ft. high. An engine of 1,200 horse-power is employed in driving the elevating-belts.
The general features of its construction are the fol lowing : It comprises a main building surmounted by what is termed the cupo la. The main driving-en gine is situated on about the ground level, at one end of the building. Along the top of the cupola at counter shaft, the full length of the building, is carried. This is driven by the engine. The main belt is of India rubber and canvas, S-ply in thickness and 00 in. wide. This runs very nearly verti cally from the engine driv ing-pulley to the pulley on the counter-shaft 150 ft. above it. All along the emintershafts are the driv ing-pulleys for working the 2( elevator- belts. These belt s ere made also of Inilia ruhlier belting. and carry steel hnekets riveted at reg ular intervals along their outside Nee. As the belt up On one side it carries up full buckets. At the top these pass over the driving-pulley and are emptied as they turn over, and then they deseend empty on he other side of the belt. From the point of delivery of the belt the graiii by grimly thoutgli inclined chutes to the main body of the elevator, and is directed by e or the other of the to any desired point. The grain the elevating-belt falls into the a a chute which rotates on a vertienl axis, whose prolongation would pass through its receiving end or mouth. Thus, when swung around on its pivot, its receiving mouth remains unchanged in position. The open ends of a utnnber of chutes leading to the garners corresponding to respective bins be low are arranged in a circle around the revolving chute or "revolver'." Each is numbered in accordance with the bin it leads to. The revolver can be swung so as to connect with any one of these. In this way one elevator is made to feed a number of bins.