US834816A - Safety device for elevators. - Google Patents

Description

PATENTED OCT.. 30, 1906. G. R. LAYMAN.

SAFETY DEVICE FOR ELEVATORS.

APPLICATION FILED BEPT.20,1905.

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- BATENTED OCT. 30, 1906.

G, R. LAYMAN. SAFETY DEVIGE FOR ELEVATORS.

APPLICATION FILED SEPT. 26, 19064 2 SHEETS-SHBET 2 aywawcoz v l/vlweooeo I arrow w UNITED sT 'rEs' PATENT OFFICE.

GEORGE R AYMAN, or LINooLN, ILLINoIs.

.S AFETY DEVICE I Specification of Letters Patent.

FOR ELEVATORS Patented Oct. 30, 1906.

Original application filed. July 8,1905, Serial Noi268,792i Divided and this application filed September 20, 1905. Serial No. 279,315.

To (all whom it may concern:

Be it known that I, GEORGE R. LAYMAN, a citizen of the United States, residing at Lincoln, in the county of Logan and State of Illinois, have invented certain Improvements in Safety Devices for Elevators, of which the following is a specification. v This invention relates to elevators, and more especially to the class of safety devices for elevators, and the present application is a division of the application for patent which i was filed by me on July 8, 1905, bearing Serial No. 268,792.

I the travel of the elevator in theshaft.

The present inventlon consists, therefore, in the particular construction and arrangement of the safety devices, all as hereinafter fully described, and-particularly set forth in the appended claims.

In the "accompanying drawings, which form a part of this specification, Figure 1- is a front elevation-of an elevator embodying my improvements insafety devices, showing the parts thereof in their normal position during Fig. 2 is an enlarged transverse sectional view to more clearly show the engaging cams or dogs which are adapted to support the car or cage undercertain conditions. Fig. 3is a similar view to more clearly illustrate the operating means for, throwing the cams-or dogs against the uprights of the elevatonshaft. Fig. 4 is a detail view to show the particular construction of the cams or dogs and the manner of supporting the same. Like letters of reference indicate like parts in all the views of the drawings. I

It will be noted that I have illustrated m invention as applied to an elevator of the classemployed in mines; but it will be obvious that the devices are readily applicable to "other types of elevators comprising a carand uprights, the latter being constructed of wood.

In the present instance A, spaced apart by means of a rectangular B B to the bottom of the car or cage, such plates being extended, as at b, to form a connection for the hoisting and lowering means. This connection in the present instance comprises a plate C, to which the connectingchains 0 are attached and to which is also at tached the hoisting and lowering cable G, the latter being by way of the usual eyebolt c and interposed compression-spring c.

the car or cage com-' prises the upper horizontal parallel beams A therefrom by means of the rods 0,

usual, and said uprights are made of wood.

I Supported beneath the parallel beams A A in brackets a and a are shafts D, and mounted upon these shafts between the aforesaid brackets 11/ and a are cams or dogs E, the latter being disposed so as to travel with the car or cage at either side of the uprights S of the elevator-shaft. These cams or dogs are fixed to the shafts so as to turn therewith ment with the uprights, and thereby arrest the downward movement-of the car or cage under certain'conditions. The cams or dogs E are each provided with three engaging members, as e, e,,and e the engaging membere being slightly in advance of the others and is bifurcated to provide separate sharp teeth e 6 while said other memberspresent straight edges and are stouter to thereby provide a stronger engagement after the aforeconstruction of cam or dog insures a positive andsecure engagement with the u right and prevents slipping, thereby provi ing for a quick stoppage of-the car or cage.

The shafts D are provided with arms (I, by

F, having the upturned slightly-yielding end members f, and said bar is connected at its center to a vertical operating-rod G, which p'asses upward therefrom through a guideplate 0;, located between the beams A A, and is connected by a chain H to the plate 0 of the hoisting and lowering connections, hereinbefore described. A spring h is interposed between the chain and rod, and the connection is such that when the weight of the car or cage is on the cable C the rod G will draw the bar F up snugly against the shafts D tothereby throw and maintain the dogs or cams out of possible engagement with the uprights S. In this position of the devices, therefore, they will not interfere with the usual running of the car. On the other hand, when the car or cage is released or not supported by the cable from any cause-for instance, by the breaking of the cablethe slack in the connections 0 C will permit the rod G and bar F to drop bygravity, and the latter being connected by the shafts D to the To provide for the attachment of safety devices, hereinafter described, the plate C carries a second plate 0 suspended said teeth have entered the upright, This,

The-car or cage travels between the uprights S, forming the elevator-shaft, as is and are adapted to be thrown into engagewhich they are connected to a transversebar I IOC cams or dogs willoperate to throw the latter into engagement with the uprights, and thereby prevent the car or cage from dropping in the shaft. As stated, this operation may be caused by gravitation of the rod and bar; but in order to'strongly force the cams or dogs into engagement with the uprights, and thereby compel the teeth to firmly engage the latter, a strong helical spring I is mounted on the operating-rod G and inter posed between the guide-plate a and the aforesaid bar F, the tendency of which spring is to more positively operate said bar, as aforesaid.

It will be noted that the cams or dogs E are located between the brackets of and 0, in which the shaft D has a bearing, and this provides a strong connection to withstand the strain when said cams or dogs are thrown against the uprights and engage the same, thereby insuring that the car will be arrested and supported until the cams or dogs are disengaged. As a further reinforcement at this point the rock-shaft D may extend into the plate B, as shown in Fig. 4 of the drawmgs.

The upturned end members f of the metal bar F will yield sufficiently to permit of the required movement of the arms d in throwing the cams into operative position, inasmuch as only a slight movement of said members is required and the spring I is strong enough for the purpose.

The operation of the improved safety devices will be readily apparent from the foregoing, and it will be seen that I provide a very simple arrangement that will be quickly thrown into operation automatically should an accident happen to the hoisting and lowering mechanism, which would relieve the car of the support of the cable. Also that the operation under such conditions is quick, positive, and effective. Furthermore, by providing the pull-cord n, which is attached to the cross-bar F, the latter may be operated manually at any time to throw the cams into engagement with the uprights for the purpose of stopping the descent of the car, this operation being provided for by having the spring h as a part of the connection between said bar and the hoisting and lowering cable. This manual operation of the safety devices may be necessary under certain conditions.for instance, should the attendant on the car notice anything wrong and desire to promptly stop the descent of the car or keep the cams in positive engagement with the uprights during its ascent.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is i 1 In a safety device for elevators, the combination with the car, hoisting and lowering cable, and uprights of the elevatorshaft, of rock-shafts carried by the car and disposed at opposite sides of the uprights of the elevator-shaft, cams or dogs fixed to said rock-shafts and adapted to engage the uprights at opposite sides thereof, a bar extending across the under side of the rock-shafts and having up turned yielding members, arms connecting the rock-shafts to said yielding members, an operating-rod connected to the bar, a chain connecting said operating-rod to the hoisting and lowering cable, a compression-spring forming a part of the aforesaid chain connection, and a spring interposed between the bar and a fixed support on the car, together with a pull-cord connected to the aforesaid bar for manually operating the rock-shafts, substantially as shown and for the purposes set forth.

2. In a safety device for elevators, the combination with the car, hoisting and lowering cable and uprights of the elevatorshaft, of rock-shafts carried by the car and disposed at op )osite sides of the uprights, cams or dogs 'Xed to said rock-shafts and adapted to engage the uprights, said cams each having three members one in advance of the others, the advanced member being bifurcated to provide a pair of sharp teeth which will enter the upright in advance of the other members, means connected to the hoisting and lowering cable for holding the cams or dogs away from the uprights, and a spring connected to said means and adapted to throw the cams or dogs in engagement with the uprights when such connection is released, substantially as shown and described.

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

GEORGE R. LAYMAN.

Witnesses:

J. E. JEWETT, A. D. GADWALLADER.

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