US98388A - Improved hoisting-machine - Google Patents

Description

ftnited tatrt @wat mijn.

GEORGE JOHNSON, OF CINCINNATI, OHIO.

Letters Patent No. 98,388, dated iDecembe/r 2 8, 41869; antedated December 1 7, 1869.

IMPRcvrzn solenne-MACHINE.

The Schedule referred -to these Letters Patent and making part of the same.

To all 'whom t may concern:

Beit known that I, GEORGE J censos, of Cincinnati, I

county of Hamilton, and State of Ohio, have invented a new and useful Improvement in Hoisting-Machines; and I do hereby declare that the following is a full, clear, and exact description thereof, reference being had to the annexed drawings, making a part of this specification, in Which- Figure 1 is a perspective, showing my improvement, and the essential parts for shifting the belt-s.

Figures 2 and 3, elevations, showing the shiftingrod at its highest point.

Figure 4, an elevation, representing the shifting-rod at its lowest p oint.

Similar letters of reference indicate like parts.

My improvement relates in particularto hoisters, where the platform, coming-iu contact with a projecting lever on the shiftirfg-rod, operates the shifter, and thereby throws the belt 'ofi' the tight pulley, automat ically. But it has an additional advantage when the rod is operated by hand, in which case it is not always known when the belts are shifted clear,

In all hoisters, where two belts are used, one of which being a cross-belt, driving a series of tight and loose pulleys, it is found diicult to throw the belts fully from the one to the other; and in case only a portion of the belt is on the tight pulley, it has not sufiicient traction to revolve the same, the belt is thereby heated, and greatly worn, and placed .under unequal strain, causing it soon to give wa'y, which increases probabilities of accidents, entailing a loss of time, and expense.

The object of my improvement is to provide hoisters, with across-head firmly attached to the shiftingrod, or which may be attached directly to the shifter, or other part connected the1'ewith,'the cross-head having projections at each end, to receive a lever, having its fulcrum in line with the shifting-rod, and a weight to its long arm, adjustable by a bolt.

By this device, whether the cross-head is lowered or raised, it elevates the weighted lever, and when the shifting-rod is started toward its middle position, the weight falls with suicient force to throw the belts entirely on the loose pulleys.

The construction of a hoister, to which my improvement is applicable, may be as follows:

A, in fig. l, is the driving-drum, carrying the straight belt l and cross-belt 2 over the tight pulley B and loose pulleys O C. s

D is the shifting-rod, sliding in boxes cl d, and extends from the bottom to the top of the building.

At convenient intervals are placed handles E, by which the rod D is operated.

F is the shifter, carrying the two 'arms' f j A collar, G, is screwed to the shifting-rod D by bolt g, which engages with one arm of lever H, while its other arm operates the shifter F.

In construction, my improvement is as follows:

At any convenient part of the shifting-rod D is bolted the arm I, to any fixed part of the building.

A. lever, II, swings on thc arm I, the poles of its A fulcrnm passing-` through the shifting-rod D.

An adjustable weight,-K, is bolted to the long arm of lever J.

L is a cross-head, bolted t'o the shifting-rod D, its two arms being set at an angle, but parallel to each other.

l and l are bolts or projections, with or without friction-rollers, which engage with lever J, it pressing downward on projection 7, and pressing upward on projec- 'tion Z'.

Theoperation of myimprovement becomes obvious. vWhen the shifting-rod becomes elevated, from the position seen in iig. 1 to that seen in H553, the weight t on lever .l oiiers less resistance as it rises, until it has 'reached nearly perpendicular to its fulcrum; this upward motion having been given the lever by pro jection'1,on cross-head L. ',ly this movement thel When the platform is to be raised, the handle E is depressed still further, when the other. projection l raises the weighted lever'J to an equal elevation, as before, as seen in' tig. 4; the decrease of resistance being as in the former operation. In this position of the shifting-rml, the platform is ascending, owing to the cross-belt 2 having been'tln'own ou the tight pul- .ley B, reversing its motion. v

When it is desired to bring the platform to rest, the handle E is elevated, which, starting the weight downward, by the projection l', relieving the lever J, it continues'its downward motion automatically, until intercepted by the projection l.

- It will be observed that with my improvement it is not necessary to adjust the shiftingrod to the exact position where it will throw the belts entirely off or on the pulleys, as the weighted lever, in all cases, holds the rod at the extreme upper or lowerpoint, or, having been started from Aeither of them, by hand, or by the platform coming in contact with the projection on the shifting-rod, the lever continues its motion antomat-icaliy, and stops just midway between these two points.

'having an adjustable Weight, K, as and for the purpose speced.

3. The combination, with the`shftingrod D, or

other equivalent parts, of the cross-head L, projections l l', lever J, and adjustable weight; K, all operating to-4 gether, as and for the purpose herein set forth. j

Witnesses: GEORGE JOHNSON. P. A. CLIFFORD, T. VAN KANNEL.

Images