US320316A - weston - Google Patents

Description

(No Model.) 3 SheetsSheet 1.

T. A. WESTON. HOISTING MECHANISM. No. 820,316. Patented June 16, 1885.

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NVENTOR' Thomas a2. 7Vston, 0 By his Attorneys N. FEYERS. Mom-Lithograph", Wnhingmn. D. C.

(No Model.) 3 Sheets-Sheet 2. T. A. WESTON. HOISTING MECHANISM.

No. 320,316. Patented June 16, 1885.

INVENTOR Thomasfl Wszon,

By his fltzorneya N. PETERS. PhoXo-Lflhognphu, Wuhi (No Model.) 3 Sheets-Sheet 3.

T. A. WESTON. HOISTING MECHANISM. No. 320,316. Patented June 16, 1885.

INVENTOR Thomas fl- Wszon, By his flttorneys N, PETERS. Photo-Lithographer, wnhin mn. D. c.

* TATES PATENT Fries.

THOMAS A. WESTON, OF STAMFORD, CONNECTICUT, ASSIGNOR TO THE YALE & TOlVNE MANUFACTURING COMPANY, OF SAME PLACE.

HOISTING MECHANISM.

ZEBPECIFICATION forming part of Letters Patent No. 320,316, dated June 16, 1885.

Application filed January 5, 1884. (No model.)

To ctZZ whom it may concern.-

Be it known that I, THOMAS A. WEs'roN, of Stamford, in the county of Fairficld and State of Connecticut, have invented an Improved Hoisting Apparatus, of which the following is a specification, reference being had to they Y accompanying drawings.

The object of my invention is to obtain a convenient and portable hoist, the brake of which can be set or adjusted so as to auto matically sustain the load, and can also be as readily set so as to be non-automatic in its action.

My invention is illustrated as applied to a pulley-block or portable suspended hoist, for which purpose it is primarily intended; but my invention is also, obviously, applicable to cranes or other hoisting-machinery.

Figure 1 is a vertical side elevation of a portable hoist embodying the main features of my invention. Fig. 2 is a horizontal transverse mid-section of Fig. 1. Fig. 3 is a vertical elevation of the inner side or brakeface of the side frame, A. Fig. at is acentral vertical section of Fig. 1. Fig. 5 is an elevation of a complete hoist with all the accessory parts ready for use. Fig. 6 is a modified detail.

A and B are the two halves or sides of the frame united by a cross-head, 0, having a suspending-hook, C.

A B are bushes or hearings in the frame and support the journals D l) of the shaft D.

K is a brake-lever fixed to the shaft D by the. key 0, and further secured thereon by the screw-nut D. The boss K of the lever K has its end of a helical or screw form. The said incline K is in contact with and can turn slightly upon the face of the corresponding incline A of the fixed bush A, for the purpose of effecting a frictional or brake action between the main sheave E F and the frame, in order to sustain or lower the load, as hereinafter explained. The large toothed sheave or sprocket-wheel E and the smaller one or hit ingsheaveF are cast together in one piece, or otherwise united, and turn loosely on shaft D.

An ordinary endless hand-driving chain, E, Fig. 5, is placed upon the sheave E and a strong lifting-chain, F, Fig. 5, to carry the load is placed upon sheave F. The ends of the chain F are secured to the frame by the studs B B. One of the chain-loops thus formedviz.,the one between the stud B and most distant side of the sheave F-carries the lower or snatch-block, G, and load. The other chain-loop receives the slack chain taken up in hoisting over the sheave F. The loaded or hoisting side of the sheave F and of the chain are each indicated by a plus mark, and the direction of motion in hoisting is indicated on the several parts by arrows. The large sheave E has lugs E on its outer-side to carry and hold a friction-disk, E, and the adjacent inner face, A, of the frame A has slots A to carry and hold, by corresponding lugs or projections thereon, the fll0l3lOl1(1lSlS A The said disks furnish an enlarged area for frictional or brake action between the sheave E and frame side A, in accordance with the specification of my United States Patent No. 75,227, March 3, 1868, for an improved coupling and brake.

The brake-lever K can be operated by the cord K", Fig. 5; but it has also an automatic action, as explained hereinafter.

The shaft D at the part occupied by the sheave-casting E F is made of larger diameter than its ends or journals D D that it may have a tendency to turn on its said ends or journals along with the sheave it supports. To further aid the shaft to turn with the sheave, the collar D" of the shaft is made as large in diameter as convenient for gaining the better frictional hold on the sheave by contact against its boss or side. The bushes A B may also be of bronze or hardened steel, to lessen the friction thereon of the journals 1) D The lever K has arms of equal length or weight, so as to be balanced and neutral; but by means of the sliding weight K upon the hand-cord K" or upon the lever it can be made to tend downward on either side, to aid or neutralize the tendency of the shaft to turn with the sheave, as above described.

A small angular movement only is required for the lever K and shaft D in its bearings, in order to carry the incline K around and upward upon the incline A and thus pull the shaft lengthwise toward the incline A, and at the same time pull the sheave E against the frame A and friction-disks, so as to retard or arrest the descent of a load.

The operation is as follows: A load being attached to the lower block, G, it may be lifted by impelling the hand-chain E and sheave E in the direction of the arrows. Upon ceasing to lift and allowing the sheave to turn back slightly, it will turn with it, by friction thereon, the shaft D. The said backward turning of the shaft carries its incline K upward upon the other incline, A simultaneously pulling the shaft lengthwise, and thereby pressing the sheave E against the frame A and frictiondisks, whereby the further descent of the load is arrested, and it may be safely left in suspension. To lower the load, it is necessary to pull back the lever K, and thus to withdraw the pressure of the inclines upon the disks E A and lessen their frictional adhesion sufficiently for the load to overcome it and descend at the desired rate of speed.

If desired, the brake action can be so diminished, by pulling the lever backward with the proper force, that the load will be barely sustained, and the latter can then be lowered by continuously pulling downward in the direction for lowering the hand-chain F.

To make the brake action non-automatic, the sliding weight K must be sufficiently heavy when placed in the position K on the cord (see Fig. 6) to resist wholly the tendency of the shaft to turn backward with the sheave. The brake can then be pulled on or off, for respectively suspending or lowering a load by using the opposite sides of the hand-cord K.

Fig. 6 represents a device for rendering more easy the control and regulation of the brakelever when pulling it off from its automatic checking action upon the load. S is a coiled spring seated at the end of the lever K. A wire rod, S, attached to the cord passes freely through the lever end, pulling thereon through the elastic medium of the intervening spring. The operator can thus feel more accurately by the force he applies the degree to which he is withdrawing the. brake, and he can thus avoid releasing the brake in excess, and so causing the too rapid descent of the load. The said elastic connection between the operators hand and the brake-shaft may, how ever, be otherwise effected. It may be a spiral spring placed at any point in the length of the cord, or it may consist of a cushioned boss for the brake-lever on the shaft D,so that the connection between the said lever and shaft may be yielding and not positive, or by the use of any other convenient expedients, such as making the lever itself yielding and elastic. This element of my invention is of use upon all brake-levers and brakes which are normallyin action and require to be pulled off or relaxed in order to lower a load. It is obvious also that the backward rotation of the drum or chain-wheel or other revolving portion of the gearing in any crane, Windlass, or hoist may be self-checked and otherwise controlled by the means hereinbefore described for checking and controlling the sheaves of the portable hoist illustrated in theaccompanying drawings.

I do not claim, broadly, the use of inclines or helical bosses or screw-surfaces, one being fixed to the hoist-frame and the other rotary for the purpose of compressing a rotary brake against the stationary frame of the hoist, for the same is found in Fig. 7 of the drawings of my English Patent No. 263, dated J anuary29, 1863. My improvements may be embodied in other forms of hoists than that illustrated-as, for example, the sheave E F might be in the form of a drum without changing the substance of my invention.

Having thus described my invention, what I claim, and desire to secure by Letters Patent of the United States, is'- 1. In combination witha hoisting-machine, ashaft which automatically oscillates to apply or remove a brake, substantially as described. 2. I11 combination with ahoisting-machine, a shaft which forms the bearing for the main chain wheel or drum, and which by the revolution of said wheel or drum oscillates toapply or remove a brake, substantially as de scribed.

. 3. In a hoistingmachine, the combination of a driving and a chain sheave or drum formed in one piece, an oscillating shaft on which the sheaves turn, a helical incline, and a stationary brake, substantially as described.

4. In a hoisting-machine, the combination of one side of the frame having aplain frictionsurface, a driving sheave or drum having a corresponding adjacent frictionsurface, and friction-disks between the two, whereby the brake mechanism is brought within thelateral thickness of the driving-sheave, substantially as set forth.

5. In ahoisting-machine provided with frietional incline braking mechanism, an adjustable weighted operating-lever, whereby the said brake mechanism is operated or made in operative, substantially as described.

6. In a hoisting-machine having an automatically-applied brake, an elastic releasing device interposed between the place of the operator and the brake, substantially as described.

In testimony whereof I have hereunto subscribed my name this 20th day of December, A. D. 1884.

THOS. A. WESTON.

Witnesses:

SOI-IUYLER MEERITT, GEo. E. WHITE.

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