US397912A

US397912A - Elevator

Info

Publication number: US397912A
Authority: US
Publication date: 1889-02-19
Anticipated expiration: 1906-02-19

Description

(No Model.)

M. HANPORD.

ELEVATOR.

Patented Feb.

[7120 671/60 7; flelanctfiono anforzi,

Nrrnn STATES PATENT rides,

ELEVATOR.

SPECIFICATION forming part of Letters Patent No. 397,912, dated February 19, 1889. Application filed February 8, 1886. Serial No. 191,174. (No model.)

T 0 all whom it may concern.-

Be it known that I, MELANCTHON HAN- FORD, of Malden, county of Middlesex, State of Massachusetts, have invented an Improvement in Elevators, of which the following description, in connection with the accompanying drawings, is a specification, like letters on the drawings representing like parts.

The object of myinvention, relating to elevators, is to provide a certain and effectual means for stopping and supporting the elevator-car in case the ropes or machinery should fail, or if the downward speed of the car should be accelerated beyond the desired limit.

The apparatus comprises a safety car-supporting device, preferably a rope hanging at the side of the car and extending from top to bottom of the well or guides in which the elevator operates and itself connected with a yielding support or cushionshown in this instance as a piston working in a cylinder of sufficient sectional area to produce a force equal to the weight of the car when the air or other fluid is under moderate pressure in the said cylinder. The car is provided with a clutch or gripping device for engaging the safety support or rope, and the said gripping device is provided with automatic actuating mechanism comprising a speed-governor, by which it is caused to engage the support when the speed of downward movement of the ear increases beyond the desired limit. Means are also provided for operating the clutch or gripping device by hand from the interior of the car. The entire safety supporting mechanism is independent of the usual car-operating ropes and mechanism, and does not depend for its operation upon the tension of the said ropes, as is the case with many of the safety appliances heretofore made.

Figure 1 is a side elevation of an elevatorcar and safety appliances for supporting the same embodying this invention, thesupporting frame-work being omitted for greater clearness; Fig. 2, an elevation 011 a plane at .right angles to that of Fig. 1 of the actuating mechanism and governor for the gripping device, and Figs. 3 and 4: a side elevation and plan view of the gripping device detached from the car on a larger scale; Fig. 5, an enlarged detail to be referred to.

The safety-support which arrests and sustains the car when the proper hoisting apparatus fails is shown in this instance as consisting of a rope, a, sufficiently strong to sup port several times the weight of the car with its maximum load, and extending from top to bottom of the path traversed by the car A. The said support a is connected with a yielding or elastic cushioning device, shown as a piston, Z), (indicated in dotted lines, Fig. 1,) working in a cylinder, 0, which may in practice be about a foot in diameter and a foot and a half (more or less) in length, and normally contains air at the atmospheric pressure, or other suitable fluid. The piston 19 is normally retained at the upper end of the cylinder by a supporting device, shown as a yielding catch, (1, (see Fig. 5,) and preferably also by a counter-weight, 6, connected by a cord or chain passing over a pulley, c, with the piston, the said counter weight being sufficient to balance the weight of the piston and its red and the rope a. The cylinder is preferably provided with an escapepassage, 0, having a safety-valve, 0 which confines the fluid in the cylinder until it reaches a certain pressure, and then permits it to escape; and the said pipe 0 may also be provided with an inwardly-opening checkvalve, 0, which permits the fluid to enter When the piston is raised, but prevents the escape of fluid from the cylinder. Thus when a heavy weight is applied to the cord to the piston b is drawn down, compressing the air below it, which exerts a constantly-increasing pressure until, it the dimensions previously given are employed, when the piston arrives at about three inches from the bottom of the cylinder the pressure is about one hundred pounds to the inch, exerting an upward force on the piston of over five tons, which is far beyond the weight of an ordinary elevator-car with its load, so that if the weight of the car were suddenly applied to the rope a it would be arrested gradually and its momentum overcome without shock, the car being brought to rest in a downward movement of about a foot and without a sudden strain 011 the rope (I, thus diltfering essentially from the usual sal:'etystops, whieh eheek the ear almost instantaneously, if at all, and. are likely to be broken by the sudden impulse.

In order to eonneet the ear A with the salety-supporti (,L in ease its other s11p1 1orts fail, the ear is provided with a eluteh or grip iing device, preferably eonneetied with the bottom thereot', consisting, essentially, ot:' a stop-plate, f, provided with a sht'tuldeigj, extt'inding from the side ol the ear, having a seat or groove to receive the rope and eonstituting one member of the gripping deviee. also provided with a eurved dovetail shoul- 15 derQf and has pivoted upon it the movable inentberf" ol the gripping deviee, which has a dovetail shtmlder engagin the dovetail projeetion f, as shown in liig. I and also has a eurved gri ')1 1i'11g-'l"aee,j, prt'ivided with a groove or seat for the rope u, the said i'aee being eeeentrn: to the pivot f oi. the arm j, so that when the said arm is turned up 'ard on its pivot its face approaches the shoulder f, wedging and gripph'tg the rope a between it; and the member l with a holding foree which inereases with the upward strain on the rope, or, in other words, with the downward strain on the gripping deviee derived t'rom the weight. and momentum ol the ear. In order to move the 111e1nber ot the gripping deviee upward, so as to seize the rope u when the downward speed of the ea r increases above a certain limit, the said niember 'f is emtneti-ted with an endless aetuating trope,

belt, or ehain, g, passing over 1 111lleys 71 71 at 1 the upper and lower ends of the elevattiirwell, so -that: the said pulleys are rotated in the upward and downward movement of the ear. An u 'nvard strain on the portion olf 40 the rope 5 eonneet'ed with andahovethe movable niemhenf ol" the gripping deviee sull'i- (-ient to overeome the weight (11' the said device will raise it and eause the sa|'ety-support u. to he seized thereby. in order to produce 115 such upward strain on the rope y when the 1 speed of downward movement of the ear iintj-rez'tses, it is provided with e i1ntrolling meehanism, shown as consisting ol :1 rattiwhet, 1', fast on the shal't t and adapted to be engagml by pawls 1' on the pulley l1, whieh is itself loose on the said shalt, but through the intervention olf the said ratchet; and pawls eauses the shaft to turn with it in its movement produeed by the rope r in the downward movement ot the ear. The said shaft-11 operates through suitable gearing, 1 1", (see l ig. 2,) a eentritugal governor, 7. the arms of whieh aet on a rod or stem, III, whieh is depressed by the governor-arms when thespeed 6o (11? the said arms inereases, so that they are thrownoutward hyeent ril'ugai 1'11101111'11111 their supports Ir. in the well-l no\\'n manner. The

said rod 112 aets on an arm, I), tixed upon a roehshaft, 7, and provided with asupporting-arm, r 1, shown as jointed, and supporting the weighted end of the :rope-eheeki11g deviee, shown as a brahe-strap, I, which extends over 'lhesaid plate is 1 the part 01: the rope 5 lying in the groove 01" the pulley 71, and is normally held out of contact with the said rope by the support '1 r, which praetieally eonstitutes a vertieal toggle-levm'. The support 1' 1", with its shall. 7) and .arm (1, eonstitutes a detent; hy whieh the brake or retarding deviee is normally prevented lrotn operating. \Yhen the governorrodm is depressed, the arm 0 will be moved dt'iwnward by it: and the roe'k-shal't 1 turned, which movement will break the joint olf the su 1port r 1", the upper part; of which rests against the stationary stop 1*, and thebral estrap will be no longer Hltlipfii'ltltl, so that its weight will draw it; upon the rope g, instantly eheeking the same, so that in the further downward movement ot the ear the griyjipingmein' her f will be raised relative thereto and grip the rope (1, which will then sustain the weight of the ear, and will cheek its 1no1nent1n11 and bring it to rest gradually through the aetion ol' the eushioning deviee eonneeted with the said support a.

It will be seen that the retarding aetion ot. the brake t on the rope g not variable, i11- oreasin g and decreasing with the speed of the governor, but that itprodnces no effect on the rope until the speed ol' the govermin' rises to a eerl'ain liitXltill'llll amount, and. then the bralce is applied with maximum effect, and its action is not removed by the subsequt nt decrease in speed orstopping of the governor.

In order that the resistanee ol' the pulley 7t and governor nieehanisin aetuated thereby may not retard the rope g sul'iieiently to cause the gripping; device to act, the said rope g maybe held down with a. yielding pressure by means of a spring, 1/, engaging a prt'ijee tion, 11, on the said rope, and an arm or bracket, 11, eonneet'ed with the elevator-ear. The 111ova-hle gripping memherjmay also be operated by an independent eord, 1, earried by suitable pulleys or guides to the interior of the ear, and provided with a handle readily z'teeessihle to the attendantinthe ear, who ean at onee operate the said gripping deviee and stop the ear, if desired, i11dea1ende11tly ol the antoniatit'r grip-aetuati11g n'1eehanisn1 previously deseribtal.

As the rope a is never called into operation in the normal worhingot the ear, and is never bent, it is not subjected to deterioratit1n by age, like the usual hoisting-ropes ol the ear, and the grip-aetnating nueehanisin is wholly inde iendent of the ear-hoisting nieehatrism, dt'ipentfling for its operation upon the dome ward speed oi the ear itsell, and not upon, the speed ol any ot the ropes or pulleys I'orming a part ol the normal ea 'aet uating meehanism.

11 is obvious that instead ol? the air-eushion any other yiehling supporting deviee-S11eh as a springor a series of weights applied sueeessi vely m ight l 1e employed to grad ual 1y arrest the downward movement 01' the su n orb ing devieo o and weight eonneeted tht'a'ewith, and that the said salfety su 'iporting device d lOO is not necessarily a rope or flexible support acting by tensile strength, but might be a strut or upright connected either at its upper or lower end, or both, with a yielding cushion.

'lhe pulley e, for the connection between the piston l) and its counter-weight 6, may be provided with a squared arbor to receive a wrench or crank for the purpose of raising the piston 1') after it has been depressed in the operation of stopping the car; or any other suitable means may be employed for raising the said piston and for holding it in its up per positionsueh, for instance, as a spring in the cylinder, which would act, in conjunction with the elastic pressure of the fluid, to stop-the piston.

It will be umlerstood that the cylinder 0 and shafts i and 1) and the governor are supported on suitable beams or frame-work like the pulleys and other overhead portions of the hoisting apparatus, and the framing or support for the said cylinder will preferably be separate from and independent of that for the hoisting-pulleys, so as to stand and afford a support for the car in case the other framework should break or give way.

ly the use of the ratchetand pawl between the pulley 7i and the governor-shaft the governor is not operatell in the upward movement of the car, so that the upward speed is not necessarily limited.

The dovetail shoulder on the gripping device receives the pressure that is exerted by the members engaging the rope (z, and, being formed in the same piece with the stationary member of the gripping device, prevents any yielding of the members with relation to one another, which might take place if the pressure were received on the pivot ol the movable member.

The arm 0 on the l'OPli-hlltlft-Z) is held up against the tripping-rod m of the governor-by a connter-weight, p, or eipiivalent.

I claim l. The combination of the salTety-support with a c 'linder and piston therein connected with said support, and a clutch or gripping 1 device l'orconnectingthe ear with the safety- 1 support, and a retaining device by which the 1 piston is held at one end of the cylinder until operated upon by the weight of the carapplied to the salety-support, substantially as described.

2. The combination of the safety-support and yielding cushion for said support, and for the car and its load when connected with said l thereby, and a checking device for said rope or band controlled by the said governor, substantially as described.

3. The safety-su1' port and a cylinder and piston therein connected with said support, the said cylinder being provided with an escape-passage, combined with a safety-valve in said passage, and a clutch for connecting the car with the safety-support, substantially as described.

4. The combination of a safety-support with a clutch or gripping device connected wit-h the elevator-ear, a rope or band connected with and actuated by the elevator-car, a speedgovernor actuated by said band, a checking device for said rope, and a detent for the checking device, and connecting mechanism between it and the specd-governor, ar *anged to be operated only by an increase of speed of the said governor, substantially as described.

5. The combination, with a safety-support, of the clutch or gripping device consisting of a plate provided with a shoulder forming one member of the gripping device, and with a shoulder for engaging the co-operatingmovable member of the gripping device, combined with the movable member consisting of the pivoted arm provided with an eccentric gripping-face, and a shoulder which receives the pressure when the gripping device is engaged with the satety-support, substantially as described.

(5. The combination of the safety-support and clutch or gripping device and its operati ng rope or band, with a governor and operating-shaft therefor, and pulley loose on said shaft that supports and is operated by the said rope or band, and a ratchet and pawl,

} one connected with said governonshaft and the other with the pulley loose thereon, as set forth, whereby the pulley operates the governor-shaft when rotated in one direction, but turns upon said gm ernor-shaft when rotating in the other direction, substantially as describel'l.

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

MELANt'VPilON HANFORD.

Witn esses:

J'os. P. LIVERMORE, H. P. Barns.