US1348201A - Safety mechanism for elevators - Google Patents

Description

C. P. BEAVER. SAFETY MECHANISM FOR ELEVATORS.

APPLICATION FILED ocr. 20, 1919.

1,348,201. PatentedAug. 3,1920.

2 SHEETSSHEET I.

rrrrrrr wvw Elmuemtoz C. P. BEAVER.

SAFETY MECHANISM FOR ELEVATORS.

0 9 IT w m dw W2 D m a P 0U m 0 2 m 0 D H N O .H A w H P A 1 0 2 8 4 3 1 avwzmtoz Car/ l fieayer- UNITED STATES PATEN OFFICE:

CARLHPOSEY BEAVER; or DUCKTOWN, TENNESSEE.

1 '0 all whom it may concern:

7 Be it-knowng that I, CARL. Poser BEAVER,

a citizen of-the United .States, residingat Ducktown, in the county of Polk, State of Tennessee, have invented certain? new and useful Improvements in Safety Mechanism for Elevators; and-I do hereby declare the following to be a full, clear,--and= exact description of the invention, suchaswill; enable others skilled in the art to which it appertains to make and use the same.

This invention relates to safety devices for elevators. V

The object of the invention is to improve the structure of safety devices for elevators, the improvements being wroughtin that type of safety devices; in, which the safety clutch members or-stops are-zheld out: of engagement When the elevator cage is suspended from the oable but, are released into, stopping position when the cable breaksso that theweight of the cage is not carriedthereby. The invention: resides, jnot only inthe provision of. the improved clutch releasing mechanism, but in the clutch members themselves and the manner in which they are mountedi';

With the above objects, view, and -such ence being had to the accompanying, draw-,

ing's. V EI-n the drawings: 1 I 1 Figure 1 is anwelevation disclosing; the general assemblage of the mechanism, f

' Fig. 2 is a ,verticalsection'on line 2 2} of Fig.1, v

Fig. 3 is a section on line 33-of Fig.1,- 7 qFig; his a section; on line 44 of Fig. 1, Fig. 5-' is.a' section similar to Fig. 4, but showing the-partsin closed position,

Fig. '6 is an enlarged d etailperspective view, 7 1

Fig; 7 is a further detailv-iew' and- ;Fjg- 8 is another detail view. Referring more particularly to; the drawings, 1 represents the rails upon-which the cage 20f aimine elevator operates. The cage ;2;may:operatezin either a vertical or an in- -clined shaft, but the elevator construction in the present instance, is thatwhich isparticularly adapted for usein inclined shafts.

-.'l"herefore,-tlie car-2 is supported unonythe rails: 1 by;-: means of cmllersvor'. nheels Specification of Letters'r'atent.

, p Patented Aug. 3, 1920;-

Application filed October 20,1919. sena1-no. 3s1,s22. i

Mounted upon the side of the car which 7 spans 'the railsl is a rackbar 4 whichds longitudinally movable, to a limited degree, within gulde members 5 secured-to the'car or. cagebody. Thelower end of the1 rack bar lis connectedto one end of a, comparatively. heavy spring 6 whose opposite endi-is is provided togwhichthe elevator cable; 11

is; secured. I The tendency of the cablel l, when it is tensioned'to lift the-cage, ,isto draw; therack bar upwardly against the tension ot the spring 6 until a balance ofj the forces has been SiZIIICk.K.MO11IltBd ind-outer brackets on bearings secured tothe side of thecage 1s a-shaft12 which extends transyersely of the rack bar-4 and-has-arpinion "13 which meshes with the teeth'oftherack bar... Also mounted upon theshaft 12-;are the worms 1 1 which mesh withwor'm gears 1 5 mounted upon the upper endsof the shafts 16. S;aiclw shafts 16 are carried in bearings 17 :disposed at. practically equal; distances the shafts 16 substantially parallel the-latter. Surrounding the shafts 1 6 are; the; coil springs 18; ,Preferably, there .are .-two

springs to each shaft, one endof each o? the springs being: connected to its respective from opposite sides of the rack .bar,-.so that I shaft and the; opposite endbeingfixed to-ene ofthe brackets or bearings 17 r or to another bracket secured to the side of; the cage. The tendency of the springs is to turn theshafts r ta ion imparted b WQPmI gears 15.-

the -.vvonns- 14 ,to the secured in a suitable manner to the side ,of

- 16 me direction-oppositeto the directionof the cage2 are theshorizontailly or trans versely s-lidable clutch :frames-20eand-21 upon which are formed the clutch elements 22 and23 respectively,v the clutch members 22 being adapted to grip the inner sides-pf the rails vwhile'the clutchmemfbers 23 are oppositely disposed-to; clutch theouter sides of the rails opposite. the members 22. The clutch members 22 and 23,1n'ay; havefgripping 'faces of any suitable form, .series of ts h be eg. nd ated v lat napins ein t nc for taking hold of the faces of the sides of the rails. The clutch frames 20' and 21 are connected in pairs to the shafts 16 by'mean's of the devices which tend to throw the melnbersof the pairs in opposite directionsiso to close or open them simultal ieously,

Thus, upon eachof the shafts 16 there are secured sets of eccentrics 24l-and'25. The eccentrics 24 extend inwardly from the shafts, with respectto the rails, and are s'ur+ rounded by eccentric straps 26 carried by the frames 20 so that rotation of the "shaft 16 tends to throw the fram'es'20 outwardly. The sets of eccentrics '25 extend'outwardly orin the opposite direction from the eccentries 24, so that as the shafts 16 are rotated, eccentric straps- 27 which are carried by the frames 21 and surround the eccentrics tend to drawthe clutch members 23 inwardly into engagement with the rails simultaneously. with the outward-movement of theclutchmembers 22.

' In-the use of'the clutch mechanism which has been described, the parts 'are held in a normally inoperative position by the tension of the weight of the cage which is suspended from the cable 11, since the upward pull of I the cable lifts'the lever 8 and'with it the rack bar 4'; When'the'rack bar 4' is lifted,

the'pini'on 13 isfrotated to operate the worms 5 '14 with result that the shafts .16 are rotated against the tension of the springs 18. This rotation of the shafts 16 separates the clutch.

members 22 and 23 sothat they clear the rails. The lift of the cable 11 draws the rack bar 4 upwardly against the tension of the spring 6,'; o that when the cable 11' is untensioned or broken, the spring 6 immediately draws the rack bar downwardly into its normal position, withthe result that the shafts "16 are 'released to the tension of the springs 18, and are also aided in their return rotation by the motion communicated to the rack-bar through the gears 13,14 andf 15. "The immediate result 'of this action is to throw the clutch members 22 and 23 into enjgagementwithjthe rails so that the car is 'stopped'f thereby "within a few inches of travel; i I i It will be apparent from the foregoing description that the elutchmechanism constitutes a very simple gripping means for stoppin'g a ear or cage" lafterfits 'lioisting cables have par-tedgand that furthermore the mechanism inadditionfto its simplicity, w'ill'act positively and with sufficient strength to stop the car even though the latter were "traveling with considerable momentum at the time the break occurred; q 'VVhat "*I claim as m invention, is

1. Asafetym'echamsm forele'vators, comprisinga longitudinally movable rack bar, a pair of shafts paralleling said rack bar, means gearing said rack bar to the shafts,

to" rotatethe latter, clutch members are ranged to grip the elevator rails, and means operated by the rotation of the shafts to close the 'elutch'members'over the rails;

2. A safety mechanism for elevators, comprising a longitudinally movable rack bar, a pair of shafts paralleling said rack bar, means gearing said rack bar to the shafts to rotate the latter, clutch members arranged to grip the elevator rails, and means pivotally supporting the clutch members on the shafts'in such relation that'rotat'ion of the latter closes the clutch members Onythe rails. i 3. A safety mechanism for elevators, comprising a longitudinally movable rack bar, a pair of shafts paralleling said rack bar, means" gearing said rack bar; to the shafts to rotate the latter, clutch members arranged to grip the elevator rails, and' eccentric supports on the shafts and carrying the clutch members so that; rotation of the former closes the latter on the rails. 1 4. A safety mechanismfor elevators, comprising a longitudinally 'movable'membena to rotate the latter, clutch ;mem'bers' arranged to grip the elevator rails, and means operated-by the rotation of the shafts =to close the clutch members over the rails. I 5; A safety mechanism for; elevators, comprising a longitudinally movable 'member, a pair of shafts paralleling said member,

means connecting said memberto the shafts to rotate the latter, clutch 'members arranged to grip the elevator rails, and 'means supporting the clutchmembers on'the shafts insuch relation that rotation of the latter 'closesthe clutch members on the rails;

6. 'A- safety mechanism for elevators, comprising a longitudinally movable member, a pair of shafts paralleling said member, means connecting said member to the'shafts to rotate the latter, clutch members arranged-to grip'the elevator rails-and eccentric supports on the shafts and carrying the clutch members so that rotation of; the former closes the latter on the rails.

7 A safetymechanism for" elevators, comprising in combination, a longitudinally movable member, a means normally holding said member at one limit of its movement,

means to connect a hoisting cable to the member tomove thel'atter againstsaid-hold 5 ing means, a pair of shafts paralleling the 'Inovable member, means gearing said memv 'be'r'to the shafts to rotate the latter when it is longitudinally moved, and clutch mem- "bers arranged'to grip the elevator rails and connected to the "shafts toclosef-when the tension of the cable is released to permit the return fof the member to normal position.

- 8; A safety mechanism for elevators, comprising in combination, a longitudinally mov'able member, ameansnorma'lly holding said member at one limit of its movement,

means to connect a hoisting cable to the 10 sion of the cable is released to permit the return of the member to normal position,

7 and resilient means normally tending to 1'0- tate the shafts into clutch opening position.

In testimony whereof, I afiix my signature in the presence of two witnesses.

CARL POSEY 2 BEAVER.

mark Witnesses:

H. W. BERRYMAN, H. C. WHrrL'ooK.

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