TANGYE'S HYDRAULIC HOIST.

TANGYE'S HYDRAULIC HOIST.

The great merits of hydraulic hoists generally as regards safety and readiness of control are too well known to need pointing out here. We may, therefore, at once proceed to introduce to our readers the apparatus of this class illustrated in the above engravings. This is a hoist (Cherry's patent) manufactured by Messrs. Tangye Brothers, of London and Birmingham, and which experience has proved to be a most useful adjunct in warehouses, railway stations, hotels, and the like. Fig. 1 of our engraving shows a perspective view of the hoist, Fig. 2 being a longitudinal section. It will be seen that this apparatus is of very simple construction, the motion of the piston being transmitted directly to the winding-drum shaft by means of a flexible steel rack. Referring to Fig. 2, F is a piston working in the cylinder, G; E is the flexible steel rack connected to the piston, F, and gearing with a toothed wheel, B, which is inclosed in a watertight casing having cover, D, for convenient access. The wheel, B, is keyed on a steel shaft, C, which passes through stuffing-boxes in the casing, and has the winding barrel, A, keyed on it outside the casing. H is a rectangular tube, which guides the free end of the flexible steel rack, E. The hoist is fitted with a stopping and starting valve, by means of which water under pressure from any convenient source of supply may be admitted or exhausted from the cylinder. The action in lifting is as follows: The water pressure forces the piston toward the end of the cylinder. The piston, by means of the flexible steel rack, causes the toothed wheel to revolve. The winding barrel, being keyed on the same shaft as the toothed wheel, also revolves, and winds up the weight by means of the lifting chain. Two special advantages are obtained by this simple method of construction. In the first place, twice the length of stroke can be obtained in the same space as compared with the older types of hydraulic hoist; and, from the directness of the action, the friction is reduced to a minimum. This simple method of construction renders the hoist very compact and easily fixed; and, from the directness with which the power is conveyed from the piston to the winding drum, and the frictionless nature of the mechanism, a smaller piston suffices than in the ordinary hydraulic hoists, and a smaller quantity of water is required to work them.--Iron.