The huge reduction gearing for the freight elevator in this Welsh textile mill was last in the long line of mill equipment to be driven. Note twisted belt that allows belt shifting and reversing of the freight car's motion. The second hoist rope in the car crosshead leads to a substantial counterweight. (T. Thomas & Sons)

(Graphic Source: Elevator World SOURCE 1997-1998)


The earliest steam engine to be located within a few feet of the bedplate had a 3-foot diameter pulley on the crankshaft. Belting led a few feet away to the drive machine the worm shaft of which was extended to hold a 16-inch pulley. No need existed for a belt-shifter for the link-motion-reversing gear on the engine could control the direction of the car. No brake was used as the worms of that period, and for some time thereafter, were single thread wherein the thread pitch did not exceed 12 degrees. The load would unlikely start from a state of rest as it would necessarily drive the engine to do so.

(Graphic Source: Elevators by Jallings)


In 1879, the Philadelphia U.S. Engineer's office requested bids upon a steam-driven elevator that would lift four tons at 50 fpm. It was to be used in both the construction and the passenger lifting phases of the Washington Monument construction in the nation's capitol.
Of the four bids received, Otis's of $18,350 was accepted for a machine that would operated upon 80 pounds of steam pressure. Otis also quoted the sum of $2,700 for the conversion to passenger use, adding "the necessary safety devices, a cab with cane settee and an oil stove!" The engineers commented that, "A large drip pan was placed under the overhead pulleys to prevent oil dripping on the car; and the wire ropes were given a coating of lamp-black and boiled oil." (Courtesy Otis)



The Chicago Exhibition of 1898 was a double celebration; the city's 60th birthday and its recovery from the devastating fire of 1871. Destruction of almost an entire downtown area allowed the nature and spirit of rebuilding that sparked major high-rise building design and construction techniques, including a new generation of elevator engines. Combining the steam engine with the reduction spur gearing on a common bedplate led to a proliferation of heavy-duty drum machines with both slack belt and slack hoist cable switches. These production packages were created by Eaton & Prince Company of Chicago (Figure 1) and Otis (Figure 2) at the turn of the



Note the flyball governor affixed to Otis's penthouse apparatus as an overspeed governor. Overspeeding of the car flung out the balls, engaging gears that activated a band brake upon the idler drum rim, effectively stopping the car. No doubt the large diameter drum was required to provide a suitable grip for the brake band.

By 1893, Otis had developed a production steam engine package with heavy slack belt roller to a shut-down switch and a shut-off
through the control cable to a valve at the steam line feeding the pistons. Note the twin hoist ropes spooling from the edges of the drums to the center, assuring a better equalization of the ropes and lessening the chance of cable overlap. The large diameter drum in the penthouse is shown at left.


Almost all steam engine/gearing packages were placed adjacent to the shaftway as was this of the J.W Reedy. Note the notched iron ratchet strips set in the wooden guide rails. Should the wagon leaf crosshead safety be set by slack ropes it was hoped that the load would be sustained upon the guides.


Otis's Patent Steam Engine package was very compact and although one end of the winding drum rested upon a pedestal, all could very well have been combined upon one bedplate.

(Courtesy Otis)


In the 1870s, compact steam engines were built by Otis and Crane using an extended bedplate for the worm gear which extended into a double crank shaft and a heavy flywheel that smoothed out the motion of the engine, particularly at low speed. With a larger drum and increased sizing of the steam ports, the usual speed of 100 feet per minute could be increased to that of the spur gear type - 200 fpm.

(Graphic Source: Elevators by Jallings)

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