US232637A - And la eoy p - Google Patents

Description

(No Model.)

G. W. PITTS,& LaJR.'P. GRIFFIN. Elevator.

Patented Sept. 28, I880.

-N.PETERS, MUm-LITHOGRAF HER, WASHINGTON, D C.

UNITED STATES PATENT. OFFICE.

GEORGE W. FITTS, OF SOUTHAMPTON, NEW HAMPSHIRE, AND LA ROY F.

' GRIFFIN, OF LAKE FOREST, ILLINOIS.

ELEVATOR.

SPECIFICATION forming part of Letters Patent No. 232,637, dated September 28, 1880.

Application filed June 8, 1880. (No model.)

To all whom it may concern:

Be it known that we, GEORGE W. FITTS, of Southampton, State ofNew Hampshire, and LA ROY F. GRIFFIN, of Lake Forest,Illinois,

have invented certain new and useful Improvements in Friction Safety-Clamps for Elevators and Similar Appliances; and we do hereby declare that the following is a full, clear, and exact description thereof, reference being had to the accompanying drawings, and to the letters of reference marked thereon, which form a part of this specification.

This invention relates to attachments f0 elevator-cabs designed to arrest the same sud- I 5 denly.

It consists in the combination, with the cab and with the fixed guides therefor in the shaft or well, of a horizontal lever pivoted to a fixed point of the cab, at one side of the guide, in

such manner as to vibrate and also to move longitudinally on said point; a clamping-head secured to one end of the lever mentioned,

adapted and arranged to bind upon the sta tionaryguide; a spring arranged to swing the lever on its pivot, and thus to throw the head into engagement with the guide, and devices connecting the lever with the hoisting-rope,

whereby the head is held against the action of the spring, out ofengagement with the guide when the rope is taut, but is released when the rope is broken.

It alsoconsists in a similar lever and head, similarly arranged and operating with reference to the guide, but located in reach of the 3 5 operator, so as to be worked by him independently of the hoisting-rope.

It finally consists in the special devices hereinafter described, and pointed out in the claims:

In the accompanying drawings, Figure l is 40a central vertical section of an elevator-cab provided with our improvement, the clamps being located beneath the cab. Figs. 2 and 3 t are detail views of the clamps and guides shown in Fig. 1, wherein said guides are shown to be of the single order, made of T-iron. Fig. 4 is a central "ertical section of a cab having my improvement located at the top of the cab, the guides being double and receiving the clamps between the an gle-plates forming said 5 guides. Fig. 5 is a horizontal section of the guide-post and guide, showing clearly the position of the clamp-head in place. Fig. 6 is a detail view of the hand-lever that works a separate clamp to stop the cab at the level of the floor, which clamp and lever are seen in 5 5 Fig. 4 applied to the cab. Figs. 7 and S are enlarged views of the plate M, shown in Fig. 4

in connection with the hand clam p-lever therein indicated.

A represents an elevator cab or car, B being the platform, and O the top or roof, when present. .D is one of two opposite posts or upright timbers extending the length of the shaft for the support of the guides E.

Th'e cab is provided with the usual shoes to run upon the guides, which shoes are not here shown. a

J represents the rope or ropes by which the cab is hoisted and lowered. I is a cross-bar to which the rope is attached, and I is one of two bars secured transversely to the ends of the cross-bar I.

In Fig.1 the iron rods K run from the lateral barsl downward through the car, and are provided with shoulders K, by which they support the car. Said rods are adapted to, move longitudinally through the car and extend below the platform B, as shown, and for the purposes that will presently be explained.

F F are strong levers, pivoted in a horizon- 8o tal position to the supports G G, which are rigidly secured to the under surface of the platform B. The levers have short slots's, (indicated by dotted lin es,) through which the pivot-- bolts a, securing them to the supports Gr, pass, so that said levers have both a longitudinal and an oscillating movementon said bolts, for purposes to be explained. At their outer ends said levers are also pivoted to the ends of the rods K. At their inner ends the levers F are provided with powerful lugs or heads H H, strongly secured to the levers, and arranged to embrace the single form of guide shown in the Fig. 1, now being described, in the manner more distinctlyshown in Fig.2. These heads, 5 when the levers F are horizontal, or when the shoulders K of rods K bear against the car, are held in position to fairly clear the guide E, the levers being drawn outward by the rods K Y or otherwise, so that the bolts a will bear against the inner ends of the slots 8, as seen in Fig. 2, and offer no impediment to the free swing out movement of the car; but when the levers of the horizontal the lugs or heads catch, one lug of each lever on one side and one on the other side of the guide, and clamp said guides so as to stop the car. In this movement the levers are drawn inward upon the bolts a, as seen in Fig. 4. It is intended that this clamping effect shall be produced only when the hoisting-rope J breaks, and for the purpose of preventing disaster in that event. To accomplish this end springs L are provided, which bear at one end against the platform and at the other against the levers F, so that when the strain is taken off the rods K, as in case of rupture of the rope, the

levers F will be swung into position by said springs to cause the lugs H to bite on the guide and thus stop the car. Said springs should be strong and lively, so as to act quickly, but obviously their strength must be insufficient to support the cab.

The form of the biting-faces of the lugs H, it is found, may be straight or curved, or beveled each way outward from the center. We prefer that they be either straight and parallel or beveled. These faces should so nearly approach the guide when not in action that but little movement of the levers is necessary to bring them into engagement with the guides E.

In Fig. 4: the invention is shown as it may be applied to the top of a cab, and the clamping-levers and lugs are shown in position to engage the latter with the guide, the hoisting-rope J being broken. Said guide is also shown in the alternative form of two angleplates fixed parallel with each other upon the upright D to form a groove. The lugs or heads H, in this case, may be single, as further shown in this Fig. 4, to run in the groove between the angle-plate guides. In this case the opposite faces of the several lugs are adapted to engage with the outer guides, as in Fig. 1, the inner faces of the lugs engage with the single guide, and the same principles of construction as to form in the faces of the lugs obtain in the single interior lug as are above set forth relative to the double lugs described. In said Fig. 4 the further modification is shown of providing chains K in extension of the rods K, instead of showing the latter movable through the car or through the cross-beam I, as would be practicable. The levers F are further shown to be actuated by springs L, which, at their unattached ends, bear upward against the loops N, which rise from the ear. These differences are the natural outgrowth of the difference in situation, and are not vital to the invention. 77

The arresting devices described areintended, as shown, to go into operation only upon the rupture of the hoisting-rope of the car. In Fig. 4. there is also shown a similar arrester independent of thehoisting-rope, intended to be operated at the pleasure of the man in charge for the purpose of stopping the car at the level of the floor. It consists of the handlever F, having the head H, like those at tached to the levers F described, said lever being allowed pivotal and longitudinal movement in the strong loop 1 (shown in section,) and being held inactive by the plate M and its coacting devices, as will be further explained.

It is a distinctive feature of the clamping lugs and levers that they act as a positive stop, and not in any case as a brake to retard motion of the car. The lugs H are arranged to bite the guides E upon very slight pivotal movement of the levers or rotative movement of the lugs, and the arrest of the car is instant upon such biting. The power of the bite is not dependent upon the force of the springs L or of the hand-appliedto the hand-lever F, but is due wholly to the weight or force operating the car.

In the case of the hand-lever the plate M is provided with a notch or hole, t, which receives a pin, 1), on the lever, said parts being arranged so that when they are engaged the lever is longitudinally and otherwise in position to hold the lug H free to move in the guides E. When the pin 19 is withdrawn from the notch or hole t, and the long arm of the lever is swung in the direction in which the car is moving, the lug H quickly engages and at once stops the car.

It is practicable with this device to stop the car exactly on the level of the floor, while by mere management of the driving power this is generally impracticable, except by several times starting and stopping. In the ease of heavy merchandise-elevators this is of great importance.

The plate M has the elevations m onits outer surface, which, by their inner faces converging from both directions to the hole 13, direct the pin 19 to enter said hole and move the lever longitudinally to its proper position to free the lever H. The pin 2 may be fixed to a spring, S, Fig. 6, which will yield under the grasp of the hand to withdraw the pins; or it may be otherwise adapted to enter and withdraw from the hole t.

After the clamping lug or lugs, either of the hand-lever F or of the levers F, have been engaged with the guide or guides E to stop the car the latter must be started in the opposite direction to release them.

In the drawings the parts are obviously not in proper proportion.

The pivots on which the levers F swing may be very near the heads H, giving to the latter a more simply rotative motion than is indicated in the drawings; but said pivotal points will always be eccentric to said heads and located at one side or the other of the central line of the guides. A single casting or wrought piece may include the lug or lugs of the-head and a trunnion, which trunnion has bearing in the car-frame, as shown, of the lever-pivot.

In connection with such a head and proximate pivotal bearing, a very slender lever may serve to rotate the lug or head into cramping engagement with the guide E, and such lever need not be rigidly attached to the head.

We are aware that clamps arranged to bind upon the guides of an elevator on the rupture of the sustaining-rope arenot, broadly, new but,

Having thus described our invention, we claim 7 1. The combination, with the elevator-cab and the stationary guide therefor, of the horizontal lever F, having the clamping-head H, and the spring L, arranged to throw the head H into engagement with the guide, said lever being pivoted to the rigid support G or otherwise to the cab at one side of the guide in such manner as to allow to the lever both a longitudinal and a vibrating movement on its pivoted point, and also being so connected with the hoisting-rope that the head H is held free of the guide when the rope is taut, substantially as described, and for the purposes stated.

2. I11 combination with the elevator-cab and the guide E, the clamping-head H, its operating hand-lever F, located in reach of the attendant, and devices substantially as described whereby the lever may be held disengaged from the guide when not in action, substantially as described.

3. In combination with the lever F, having the clamping-head H, arranged in an elevatorcab to act with the guide E as a stop to the cab, said lever having both a pivotal and a longitudinal movement, the catching device consisting of the pin 10, attached to the lever, and the fixed plate M, having the notch t, and the elevation m, which guides the pin into engagement with the notch, all substantially as and 'for the purposes stated.

I11 testimony that we claim the foregoing as our joint invention we a-ftiX our signatures in presence of two witnesses.

GEORGE WV. FITTS. LA ROY F. GRIFFIN.

Witnesses to signature of Geo. W. Fitts:

JAooB EATON, FRANK B. SWAIN.

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