US718328A - Safety appliance for dumb-waiters. - Google Patents

Description

No. 718,328. 4 PATENTED JAN. 13, 1903. H. DONOHOE.

SAFETY APPLIANCE FOR DUMB WAITBRS. APPLICATION FILED JUNE 5. 1902.

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UNITED Y STATES PATENT OFFICE.

HUGH DONOHOE, OF NEW YORK, Y.

SAFETY APPLIANCE FOR DUMB-WAITERS.

bPECIFICATION forming part Of Letters Patent N0. 718,328, dated January 13, 1903.

Application filed June 5, 1902. Ser al No. 110,298. (No model.)

To all whmn it may concern.-

Be it known that I, HUGH DONOEOE, a citizen of the United States, and a resident of the city of New York,.borough of Manhattan, in the county and State of New York, have invented new and useful Improvements in Safety Appliances for Dumb Waiters, of which the following is a full, clear, and exact description.

My invention relates to dumb-waiters, my more particular object being to produce a safety appliance for the purpose of preventing the waiter from falling in the case of breakage of the hoisting-cable.

Reference is to be had to the accompanying drawings, forminga part of this specification, in which similar characters of reference indicate corresponding parts in all the figures.

Figure 1 is a central section showing a dumbwaiter equipped with my invention. Fig. 2 is a somewhat similar view, but showing the parts in a different position; and Fig. 3 is a fragmentary inverted plan View of a part of the mechanism shown in the upper left-hand corners of Figs. 1 and 2, respectively.

The waiter-shaft is indicated at 1 2 and is provided with vertical guides 3 in the usual manner. The waiter proper is indicated at 4 and is actuated by a hoisting-cable 5, substantially in the usual manner. The stationary cable 6, parallel with the shaft and with the hoisting-cable, is provided for the purpose of holding the waiter in case the hoisting-cable breaks. Mounted at aconvenient point upon the ceiling of the waiter is a bracket consisting of a heart-shaped plate 7, secured in position by means of screws 89 and provided with depending flanges 11 11. This bracket has a shoe 12 integrally mounted thereon and provided with' an arc shaped guide 13, the shoe and guide together com pletely encircling the stationary cable 6.

A lever 14 is pivoted at 15 upon the bracket between the flanges 11 11 and is provided with a shoe 16 for the purpose of directly engaging the stationary cable 6. Upon a pivot 17 is mounted another lever 18, this lever being provided with a revoluble roller 19, the lever being free to move radially upon the pivot 17, so that said revoluble roller 19 is free to actuate the lever 14 whenever the lever 18 is moved. The lever 18 is provided at its socalled free end with an aperture 20, and a bolt 21, provided with an eye 22, projects through the aperture 20 and is engaged by nuts 23. A spiral spring 24 surroundsa part of the bolt 21 and normally presses upon the lever 18. A substantially bell-shaped bracket 25 is mounted centrally in the top of the waiter, as shown, and the upper end of the spiral spring engagesthe said bracket internally, as indicated in Figs. 1 and 2.

The operation of my device is as follows: When the weight of the waiter is thrown upon the free end of the lever 18, this end is moved upward, thereby compressi'ngthe sprin g 24, as indicated more particularly in Fig. 1. With the lever in this position the several parts eX= ercise their usual relation to each other-that is to say, whether the waiter be raised or lowered the spring 24 is usually compressed, as indicated in Fig. 1. ing-cable 5 is broken, the elasticity of the spring 24 immediately asserts itself, the long or free end of the lever 18 is instantly thrown down, and the revoluble roller 19 is forced into engagement with the lever 14, thereby pressing the shoe 16 into contact with the stationary cable 6, thus locking the waiter upon the stationary cable. It will-be noted, therefore, that the two levers 14 and 18 constitute when taken together a compound lever in which the pressure is progressive-that is to say, the greater the, downward movement of the free end of the lever 18 the harder will be the pressure exerted by the shoe 16 upon the stationary cable. It will be understood, of course, that the shoe 12 is provided internallywith a friction-surface against which the cable 6 bears when the cable is pressed uponby the shoe 16.

By comparing Figsul and 2 it will be noted that in Fig. 1 the revoluble roller 19 is nearer the shoe l6 and"farther from the pivot 15 than is the case in Fig. 2. From this fact it follows that the pressure exerted by the shoe 16 varies with the radial position of the lever 18 and is progressive.

' Having thus described my invention, I claim as new and desire to secure by Letters Patent- A safety device for dumb-waiters, comprising a movable longitudinal member for hoisting the waiter, a stationary longitudinal mem- If, however, the hoist- ICO her disposed parallel with the path of said Waiter, a bracket mounted upon said waiter and provided with a friction-surface for engaging said stationary member, a lever movablymounted upon said bracket and provided with a shoe for engaging said stationary 1ongitudinal member, a second lever pivoted upon said bracket and provided with a revoluble roller for engaging said first-mentioned lever, a spring for normally pressing said secend-mentioned lever into engagement with said first-mentioned lever, and means for connecting said second-mentioned lever with said movable longitudinal member and for hoisting the Waiter.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

' HUGH DONOHOE.

Witnesses:

JNo. M. BITTER, WOLTON HARRISON.

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