US347778A

US347778A - eaton

Info

Publication number: US347778A
Authority: US
Publication date: 1886-08-24
Anticipated expiration: 1903-08-24

Description

(No Model.) 3 ASheets--Sdwet 1. T. W. EATON?. E. PRINCE 8u J. H. LIVESE'Y.

SAFETY BRAKE POR ELEVATORS.

No. 347,778. Patented Aug. 24, 1886.

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3 Sh-eets--Sheet 2. T. W. EATON, F. H. PRINCE 8v J. H. LIVESEY.

(No Model.)

SAFETY BRAKE FOR ELEVATORS.

PatentedAug. 24, 1886.

vif W Ehe (No Model.) 3 Sheets-Sheet 3.

T. W. EATON, F. H. PRINCE & J. H. LIVESEY. SAFETY BRAKE POR ELEVATORS.

No. 347.778. Patented Aug. 24, 1886.

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guides are provided with gibs b b.

UNITED STATES PATENT arten.

THOMAS XV. EATON, FREDERICK H. yPRINCE, AND JOSEPH H. LIVESEY, OF CHICAGO, ILLINOIS, ASSIGNORS TO SAID EATON AND PRINCE.

SAFETY-BRAKE FCR ELEVATORS.

SPECIFICATION forming part of Letters .Patent NoY 347,778, dated August 24, 1886.

Application tiled December '10, Serial No. 114.013. (No model.)

T @ZZ whom t may concern:

Be it known that we, THoMAs W. EATON, FREDERICK H. PRINCE, and JOSEPH H. LIVE- sEY, citizens ofthe United States, residing in Chicago, in the county of Cook and State of Illinois, have invented a new and useful Improvement in Safety-Brakes for Elevators, of which the following is a specification.

This invention relates to safety-brakes for elevators; and it consists in the novel features hereinafterset forth and claimed.

In the accompanying drawings, which form a part of this specification, and inwhich similar letters of reference i ndieate like parts, Figurel is a bottom View of an elevator-car having our improved brake applied thereto. Fig. 2 is an enlarged side elevation ot' the car and ways, showing also the cable for operating the wheels by which the brake is operated. Figs.

8, 4, and 5 are sections upon the lines 3 3, 44, and 5 5 of Fig. l, respectively.

In the drawings, A represents the guide- Ways or track up and down which the elevator travels. These ways are of uniform dimensions, eXcept toward the bottom, where they increase in width, as illustrated in Fig. 2, sufficiently to take up any looseness orleeway with which the ordinary guides borne upon the ear B fit upon the side of said ways. The One may be adjustable by set-screws b2, while the other is free to be forced suddenly against theguideway by the cams and their actuating mechanism, now to be described.

C C are cams upon the ends of a shaft, C', preferably square in cross-section, and each of said cams bears against one of the movable or free gibs b'b. Said shaft is held in bearings attached to the under side of the car, and at C2 is a toothed segment secured upon it. Meshing with said segment is a pinion, C, loose upon a shaft, C". This latter shaft earries also a clutch, the nonsliding half C5 whereofis fast to said pinion C, and the sliding half C is moved into engagement with the nonsliding part, when occasion requires, by the lever C7, connected to it by the fork c.

The manner of releasing the lever C7 so it may close the clutch is as follows: A cable or chain, D, fast at d, passes first under and over a pulley attached to the gear D', thence over another pulley attached to the gear DE, said gears being bornel upon the ear and intermeshing with each other, and from thence said cable passes down to and under astationary pulley, D3, and over another stationary pulley, D", a weight. D5, being` attached to its end to keep it taut. and insure the Working of the gears D and D2.l Instead of keeping the rope taut by a weight, it may be secured fast at some point bel-ow the travel of the car, provided the stretch is taken up whenever requisite. The weight is to be preferred, however, as it is a constant quantity, and automatically performs this duty of keeping the rope sufic'iently tight to rotate the gears. The purpose of passing the rope around two pulleys and gearing those pulleys together is to prevent slipping, and insureV such power as will rotate the governor, soon to be described.

The gear D actuates the shaft C, already mentioned, and with it the governor formed of the balls DD, secured upon springs DT D7, which are in turn secured to a fast collar, D8, at one end, and a loose or sliding collar, D", at the other end. The balls carry small projections d', adapted to strike the elbow-trigger E, by which said lever CT is held from actuat ing the clutch into engagement. and said pro jections are caused thus to strike said trigger whenever the motion of the shaft C4 becomes so speedy as to cause the governor-springs to expand sufficiently to bring about contact between the balls and the trigger. Thelever C7 being pivoted at c and sustained at the other end by the trigger, it follows that when the trigger is withdrawn, as it is when struck by the governor-balls, the lever, under the pressure of the spring C8, swings on its pivot and forces the clutch together.

With the brake thus constructed the operation is very simple. As the car descends, tl.e cable operates the pulleys upon the governorshaft, and when the movement of the car is at the ordinary speed the governor does not expand under the centrifugal action sufiieiently to cause contact with the trigger. It, however, the movement of the car becomes more rapid than safety warrants, the revolution of the governor is increased in speed accordingly, and with this faster revo]utionthegovernor eX- pands until it strikes the trigger and compels IOC it to releaseA the lever CT. This brings the parts of the clutch together and results in the actuating of the pinion C3, the segment, the square shaft, and the cams, and the gripping of the ways by the gibs under the pressure from the cams. lfthe car be near the bottom of the ways at this time, the widened ways will supplement the brake by increasing the friction between the gibs and the ways. lt is not necessary that the ways be thus widened; but we deem them a valuable auxiliary to the brake, and they may be employed with other brakes to advantage. By extending them below lthe ordinary path of the car to a suitable distance, and widening them gradu ally to an extent which will absolutely stop the car, the safety-brake may be altogether dispensed willi. ln Fig. 2 the ways are shown widened in this manner, and in such cases we recommend that they be constructed to take up the play of the guides at about the point where the car stops its descent in its regular trips, and from thence downward they should widen still further to insure the stoppage. Both in this form of the invention and in the other where the lesswvidened ways are eu1- ployed in connection with the safety-brake, a very gradual stoppage of the car in case of accident may be relied upon.

The governor in our improved brake'is attached to the bottom of the car. This saves the train of mechanism for actuating the gripping parts of the brake necessary where it is located above the car, simplifies the brake as a whole, and avoids liability to get out of order.

The cord f lnay be employed to raise the lever C7 to its normal position.

The governor may be operated otherwise than by the cable and pulley,'if some other way is preferred. The weight may bc attached to the cable at any point below the lowest point in the travel ofthe car, if room can be had to suspend it there, theonly object obtained by carrying the cable around the stationary sheaves shown being to permit the ,attachment of the weight at a point above,

where such room is usually available.

We claiml. The combination, with an elevator-car, 5o of anl expansible governor operated by the descent of the car, mechanism for carrying motion from the governor to the gibs which grip the elevator-ways, a clutch for connecting the governor with said mechanism, and means set in motion by the expanded governor for closing the clutch, substantially* as specifed.

2. The combination, with the movable gib and its cam, of the cable D, the expanding governor operated by the cable, the trigger, (o the lever,the clutch, the pinion, the segment` and the shaft upon which the segment and cam are mounted, substantially asspecitled.

3. The combination, with a car having a safety-brake, of guideways slightly widened at the bottom, substantially as specified.

4. The guideways extended below the ordinary path ot' the car and gradually widened' in such extended part to create the friction with the car necessary for its stoppage, in combination with the car, substantially as specified. y Y

5. The combination, with the governor, of its actuating-cable, the two pulleys around which said cable passes, and the intermeshing 7 5 gears attached to said pulleys, whereby the power imparted to bot-h said pulleys by the cable is utilized in operating the governor, substantially as specified.

6. In an elevator safety-brake, the co|nbination, with an expansible ball-governor, of a trigger located relative to the governor, substantially as shown, whereby said triggeris operated directly by contact therewith of the governorballs, essentially as specified.

THOMAS V. EATON. FREDERICK H. PRINCE. JOSEPH H. LIVESEY.

Titiiesses:

H. M. MUNDAY, TAYLOR E. BROWN.