US1126261A - Brake apparatus for elevators. - Google Patents

Description

M. E. NBENAN. BRAKE APPARATUS FOR BLBVAToRs.

APPLICATION FILED APB. 1, 1907.

INVENTOR ATTORNEY *HE NORPW PETERS CO.. PHOTOLITHD.. WASHING TON. D4 C.

M. E. NEENAN.

BRAKE APPARATUS FOR BLBVATORS.

APPLICATION FILED APRA 1, 1907.

Patented Jan. 26, 1915.

2 SHEETS-SHEET 2.

WITNESSES:

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@WWW/k ATTORNEY THE NURRIS PETERS 60 PHOTO-LITHO.. WASHINGTON. D. C.

FEED STATES PATENT FFlCF.,

MICHAEL E. NEENAN, OF NEW YORK, N. Y., ASSIGNOR TO NEENAN ELEVA'IOR COMPANY, OE NEW YORK, N. Y., A CORPORATION OF vNIEVV YORK.

BRAKE APPARATUS FOR ELEVATORS.

Specification of Letters Patent.

Patented Jan. 26, 1915,

To all whom it may concern Be it known that I, MICHAEL E. NEENAN, a citizen of the United States, residing at 380 lV est One Hundred and Twenty-fifth street, in the county of New York and State of New York, have invented a new and useful Improvement in Brake Apparatus for Elevators, of which the following is a specification.

My invention relates to safety devices for rope drive elevators, and one of its objects is the provision of simple and eflicient brake apparatus for rope drive elevator systems, and although it is shown applied to the type of elevator disclosed and claimed in Patent No. 912,256 granted to me on February 9, 1909, for an improvement in elevators, it may have a general application.

A further object of the present invention is to include in such brake apparatus a tension-holding device.

More particularly it is the object of my invention to provide brake apparatus including a tension-holding device to prevent the car from falling if the power-transmitting means or driving cables become broken or deranged.

Other objects of the invention will appear hereinafter, the novel combination of elements being pointed out in the appended claims.

Figure 1 illustrates a rope drive or traction elevator of the type disclosed in said patent with my invention applied thereto; Fig. 2 shows a modiiication of the invention; F 2a is a modification of a detail of Fig. 2; Fig. 3 is an enlarged sectional view of the tension-holding device shown in Fig. 2; Fig. 4 is an elevational view of another modication; Fig. 5 is a further modification; Fig. 6 is a modification of a detail of Fig. 4; Fig. 7 is a modiication of Fig. 1 and in addition shows a fixed brake shoe for the hoisting sheave; and Fig. 8 is a further modification.

Similar characters of reference designate similar parts throughout the various views in the drawings.

Referring to Fig. 1, S designates the driving sheave which may be operated by means of any suitable source of' power, as for instance, an electric motor directly connected thereto. VV designates the counterweight mounted on the yoke 13 which in turn is connected to the car C by means of the cable or cables 15 passing over the hoisting or suspension sheave 16. Journaled at 12 to the yoke 13 are the disks 5 and 8, each provided with a peripheral groove to receive the driving cable 4 which constitutes the power-transmitting means. The disks 5 and 8 are shown as of different diameters for the sake of simplicity in tracing the cable 4. 1f desired, the disks 5 and 8 may be a single sheave with two or more grooves in its periphery. The driving cable 4 is fixed at 3 and extends upwardly over the sheave 8, then downwardly around the underside of the driving sheave S, thence upwardly around the overhead sheave 6 which is mounted on a fixed pivot or fixed bearings on the fixed overhead beam 7; thence the cable 4 passes downwardly around the suspended sheave 5, again upwardly and around the sheave 2 mounted on or suspended from the iixed beam 7; thence diagonally and upwardly over the sheave 9 also mounted on the fixed beam 7, and finally to the point 10 where it is fixed to the pivoted lever, in this instance a pivoted beam. This point 10 is at the left-hand end of the lever 11, as viewed in Fig. 1, its other end being pivoted at 29 to the link 46 which in turn is pivoted at 14 to the fixed overhead beam 47. On this beam at an intermediate portion is journaled the hoisting sheave 16. The journals of the shaft carrying the sheave 16 are preferably mounted in the bearings fixed to the lever 11 which is prei? erably composed of a double beam so as to equalize the downward strain thereon. Each of these bearings is provided with an extension 44, preferably circular in form, as shown, and acting as a guide block moving in the vertical guideway 45 formed by the channel irons 1 suitably fixed to the overhead beams 47. 1t should be understood that there are two beams 7, one back of the other, and two beams 47, one back of the other, and duplicate guideways 45 similarly arranged.

The apparatus thus far described is substantially the same as that illustrated in Fig. 3 of Patent No. 998,629 granted to me July 25, 1911, for an improvement in ten sion beams for frictional driving apparatus.

In the present application, however, the connecting point 10 in Fig. 1 has been moved to the outer end of the beam or lever 11.

1 will now describe my improved brake apparatus.

Connected between the beams 11 at 28 is one end of a brake strap 2e which extends upwardly and over the hoisting sheave 16 and carries on its underside the brake shoe 27 in contact with or in close proximity to the upper side of the sheave 16. This brake shoe may be of such a shape as to not only be brought in contact with the peripheral portion of the sheave 16, but also with the hoisting cable 15 lying in the groove in said sheave. This is indicated in Fig. 3 by the brake shoe which is shown in section, and adapted to be brought into contact both with the cable 15 and with the peripheral portions of the sheave 16 shown in Fig. 2. The right-hand end of the strap 24: is provided with an extension 23 which is screw-threaded at its lower end to receive the nut 25 which is for the purpose of adjusting the tension of the spring 26 lying between the washer next to said nut and the lower right-hand end of the brake lever 21 which is pivoted at 22 between the beams 11. The extension 23 may pass through the right-hand arm of the lever 21 and be provided with a collar 23 fixed thereto so as to limit the downward movement of the strap 241 relatively to the right-hand arm of the lever 21. The lever 21 extends to the left from the pivotal point 22 and normally rests in a position out of contact with the sheave 16, but is of such a shape as to form a brake shoe arranged to be brought into frictional engagement with the lower portion of the sheave 16 so as to assist in retarding the sheave 16 as `well as to perform other functions hereinafter described. Connected to a slot 20 in substantially the central portion of the lefthand arm of the lever 21 is a piston 18 which is arranged to move in the dash-pot cylinder 17 mounted in fixed position between the beams 4:7. The piston 18 is hollow and provided with an opening 19 in its bottom. As shown in Fig. 1, the piston 18 extends only slightly into the Vcylinder 17. Both the piston 18 and the cylinder 17 are shown in section and comprise a simple form of dash-pot device that may be used,

. but it should be understood that other forms may be employed, as for instance, that illustrated in Fig. 3. The parts are so adjusted that normally the brake shoe 27 is out of engagement with the sheave 16 which is accomplished by the balancing effect of the left-hand arm of the brake lever 21 and the dash-pot piston 18 hanging therefrom in the slot 20. Now it should be noted that if the driving sheave S is stopped while the car is traveling downwardly, the inertia of the car will exert a downward stress on the beams 11 at the points 44: and thus tilt said beams about their pivots 29 and bring the sheave 16 into engagement with the brakelever 21. At the same time the point 28 travels downwardly with the sheave 16, but this has no eect in changing the relative position of the shoe 27 with respect to the sheave 16. When, however, the sheave 16 strikes the brake-lever 21, said sheave will be retarded. The brake-lever 21 is turned about its pivot 22 as soon as the beams 11 begin to move downwardly, the downward movement of the left-hand arm of the brakelever 21 being resisted by the dash-pot. 1t will, therefore, be seen that when the sheave 16 moves suddenly downwardly, the beams 11 and the brake-lever 21 tend to close together like a pair of shears. This has the effect of compressing the spring 26 and bringing the brake shoe 27 also into engagement with the sheave 16, or tightens the same thereon. Any further downward movement after the sheave 16 strikes the lever 21 is also resisted by the dash-pot, but it is evident that by reason of the slot 20, the piston 18 may be projected into the cylinder 17 to any extent desired. 1t should be particularly noted that in thus overcoming the inertia of the car in stopping the same in its downward travel, the dash-pot must resist downward movement of the brake-lever 21, and to prevent a rebound of the car this dash-pct may also resist movement in the opposite direction. If too great a load is placed on the car or if the driving rope a should become broken or deranged in its connections so as to release the beams 11, it is evident that the sheave 16 will drop or fall on the lever 21, after which, further shoe 27 into engagement with the upper portion of the sheave 16. After the sheave 16 reaches the lever 21, further movement is resisted by the dash-pot device, but such further movement causes additional turning of the lever 21 on the pivot 22, and, therefore, additional compression of the spring 26 and a tightening of the shoe 27 on the sheave 16. 1t will, therefore, be seen that the greater the downward travel of the sheave 16 the more tightly the shoe 27 will be brought into engagement with the periphery of the sheave 16 and the rope 15 lying in the groove thereof. 1t may be, therefore, said that if the power-transmitting means becomes deranged so as to release the beams 11, the brake will be applied on the upper portion of the sheave with a pressure varying with the load in the car, for the greater the load the more downward pressure will be exerted by the sheave 16 on the overhead fixed beam 7 lever 21 to cause the right-hand arm of said lever to pull the strap 24 against the sheave 16, the other end of said strap being fixed to the beams 11 at 28. With such an arrangement the car may be kept from falling even though the counterweight connection with the hoisting cable 15 should be disrupted, provided the construction is such that the brake apparatus will be applied with suficient force for the load carried.

Referring now to Fig. 2, it will be seen that the driving cable 4 is attached to the at 10 and extends downwardly around the `counterweight sheave 5, thence upwardly around the suspended sheave 6', downwardly around the driving sheave S, upwardly around the counterweight sheave 8, and thence to the fixed point 3. rlhe sheaves 5 and 8 are pivoted at 12 to the yoke 13 which also carries the counterweight W and which is connected by the hoisting cables 15 passing around the suspension sheave 16 to the car C. The sheave 16 is journaled at 35 in the yoke 37, the latter being more clearly shown in Fig. 3. Fixed to the lower end of the yoke 37 and extending across the bottom thereof in close proximity to the lower portion of the sheave 16, is the brake shoe or pocket 34. The latter is for the purpose of receiving and supporting the sheave 16 and acting as a brake thereon to stop the car if the shaft or bearings at the point 35 should become deranged so as to allow the sheave 16 to fall. The sheave 6 is suspended by a yoke which is connected by the cable 33 passing around the lever-sheave 30 to the yoke 37, as shown in Fig. 3. rllhe right-hand end of the connection 33, as viewed in Fig. 3, is attached to the cross piece 42 which in turn is attached to the yoke 37. It will, there fore, be seen that the cable 33 affords a direct connection between the sheaves 6 and 16. rlhe lever-sheave 30 for receiving the connection 33 is mounted between two beams so that lateral extensions 32', of said sheave 30 will rest on the knife edge bear ing 31, and said sheave being restrained from lateral movement by the rollers 32, 32. The apparatus shown in Fig. 2 with the sheaves of the brake mechanism and the brake receptacle 34, is substantially the same as the construction shown in Fig. 3 of said Patent No. 998,629, hereinbefore referred to.

To illustrate that the sheave 30 has only a limited degree of movement, I have shown in Fig. 2a a modification showing clearly a simple lever having arc-shaped ends, the connection 33 of Fig. 2 being divided into two connections 33 and 33 fastened respectively, at 99 and 99 to the arms of the lever 30. Furthermore, in place of the knife edge bearing 31, an ordinary bearing 31 may be used.

Associated with the upper portion of the sheave 16 in Fig. 2 is a brake shoe 40 normally held out of contact with said sheave by means of the spring 63, more clearly shown in Fig. 3. Fixed to the brake shoe 40 at its central portion is a bolt 43 which extends upwardly through the cross piece or partition 41. rlhe spring 63 encircles this bolt between washer 64, the position of the latter, and, therefore, the tension of the spring, being regulated by the nut 65 which also holds the spring in proper position. The spring 63 resting on the cross piece 41 which is fixed to the yoke 37, acts upwardly against the washer 64 and effects a pull on the rod 43 to hold the brake shoe 40 out of contact with the sheave 16. The normal position of the brake shoe 40 may be adjusted by the set screws 38 which may be locked in adjusted position by the nuts 39. ln this instance the brake shoe 40 isof such a shape as to engage both the periphery of the sheave 16, a portion of the groove therein, and that portion of the rope 15 which happens to be immediately under the brake shoe. Obviously the details of the brake shoe may be varied as desired. Also connected to the brake shoe 40 is the yoke 36 which extends upwardly and is pivoted at its shoulders 50, 50 to the dash-pots A, A. The connection 33 passes through the horizontal upper portion of the yoke 36 at 101. The dash-pots A, A have their other menr bers pivoted at 54, 54 between the beams 7. The dash-pots A, A should be such as to resist upward movement of the yoke 36 and permit free downward movement thereof. Although I have shown two dash-pots, there may be only have shown in Fig. 3 one form of dash-pot that may be used. The cylinder 52 is in this instance pivoted at 50 to the yoke 36 and receives the close fitting hollow piston 53 which is pivoted at 54 to the beams 7 in any desired manner. In the bottom of the hollow piston 53 is the check valve 56 opening downwardly; also a small opening 59 adjusted by means of the needle valve 60 screw-threaded through the upper portion of the piston 53 and provided with a thumb piece. rlhe receptacles 52 and 53 are filled with oil when the piston 53 is in its lowermost position, or so that the entire dash-pot as illustrated in Fig. 3 vill be lled with oil or other non-elastic Huid or liquid. The upper end of the receptacle 53 is open to the atmosphere.

To explain the operation of this device, let it be assumed that the car is traveling downwardly and the driving sheave S is suddenly stopped. In such event the inertia of the car will tend to pull the sheave 16 downwardly and consequently also the yoke 37 and pull upwardly the sheave 6 to the cross piece 41 and theone or more than two. By way of illustration I tighten the leads on both sides of the driving sheave S. TheV downward movement of the sheave 16 is not resisted by the dash-pots if the dash-pot is as illustrated in Fig. 3, but any rebound of the car is prevented, for, as soon as the yoke 37 travels upwardly, the sheave 16r strikes against the brake shoe 40 which is now held or resisted against upward movement by the dash pots. This is clear from an inspection of Figs. 2 and 3, v when the yoke 36 and the brake shoe 4:0 are considered as substantially stationary and the yoke 37 with the sheave 16 traveling upwardly. The upward travel of the yoke 37 is permitted by the resiliency of the spring 63 which instantly takes up or absorbs the shock due to the reaction of the car. Furthermore, besides the prevention of teetering of the car, the tension of the driving rope is .held by the dash-pot devices which can be brought back only slowly to their original positions.

ln Fig. 5 l have shown a frictional driving elevator system in which the driving cable is continuous with the car-suspension cable, or may be considered as a single continuous cable. Une end of this cable is fastened at 12 to the yoke 13 which carries the sheaves 5 and 3 and the counterweight lV; also at its upper end the sheave 102. From its connection to the yoke 13, the cable fr passes downwardly around the sheave which has a fixed pivot or bearing; thence upwardly around the sheave 8, down around the driving sheave S, up around the sheave 6 mounted on the pivoted lever 89, down around the sheave 5, up around the sheave 97 pivoted on the lever 95, down around the sheave 102, up around the car suspension sheave 16 mounted on the fixed overhead beam 47, and finally down to the car C Associated with the sheave 16 is the brake shoe 96 which is connected to the lever 95. One` end of the lever 95 rests on the fixed beam 98, and its other end is pivotally connected at 9st to the link 93 which in turn is pivotally connected to the right-hand end of the lever S9 which is pivoted at 90 to the fixed beam 91. The left-hand end of the lever 39, as viewed in Fig. 5, rests on the xed beam 88 which acts as a positive stop for the downward travel of the lever 89. The left-hand end of the lever 89 also rests on the strong spring 67 which always exerts an upward thrust on the sheave 6 to place the entire rope drive system in tension, particularly the leads in proximity to the driving sheave. The weight of the car and its load is ordinarily sufficient to compress the spring 37 and bring the lever 39 into engagement with the stop 83, the sheave 6 being mounted between the stop 38 and the pivotal point 90. This causes an upward pull at the point 92 on the link 93 and the lever 95 against the stop 98 to which the lever 95 may be pivoted if desired. The tension on the rope drive system also exerts a downward thrust on the sheave 97 mounted on the lever v95, thus tending to bring the brake shoe 96 into engagement with the sheave 16 and hold the lever 95 against the stop 98. The brake apparatus may be so arranged that the shoe 96 will be applied to the sheave 16 to prevent teetering of the `car due to the stretching of the rope system 1n stopping. .Tf the downward inertia of the car and its load is suiiiciently great, the

pull on the sheave 97 may apply the shoe 9.6, and when the car travels upwardly relieving the tension, the spring 87 may apply the shoe 96. And, should any portion of the driving cable become broken or its connections become deranged so as to relieve the tension sufficiently on the portion of the cable passing over the sheave 6, the spring S7 may be permittedto act to 4lift the lever 89 and lower the lever 95 so as to effect the application ofthe shoe 96 directly to the sheave 16 and the portion of the cable l that happens to be thereon. It will thus be seen that in case the rope drive becomes deranged, the brake will be applied immediately to the suspension sheave and held so applied to stop the car and prevent the same from falling.

ln Fig. 4l the driving cable is fastened at the point 3, passes upwardly over the sheave 8, down around the driving sheave S, up over the overhead sheave 6 on the fixed beam 7, down around the sheave 5, up over the sheaves 66 and 67 on the fixed beam 103, and thence t0 the tension weight TW which is movable in the guide 66. As before, the sheaves 5 and 8 are pivoted at 12 to the yoke 13 which carries the counterweight W and which is connectedk at its upper end to the suspension cable 15 which extends upwardly over the suspension sheave 16 to the car C. The suspension sheave 16 is mounted on the xed beam i ii7 to which is pivoted at 81 a link 80 pivoted at 79 to the brake lever 76.` The lefthand end of the brake lever 76 is pivoted at 75 to thelink 74 which is pivoted at 73 to the lever 69 pivoted at 70 to the fixed beam 71. 72 designates a fixed stop to limit the downward travel of the lever 69. This stop may be omitted, however, if desired. The lever 69 is arranged in the path of travel of the tension weight W', but below itsnormal limit of movement. Above the sheave 16 is a brake shoe 78 which is preferably pivoted at 77 to an intermediate portion of the brake-lever 76. This brakelever may be of any form desired, and at a point between the brake shoe 7 8 and the pivot 75 is placed a spring 82 in such a manner as to exert an upward thrust on the brake lever 76` to hold the brake shoe 7S normally out of contact with the sheave 16.

1n this instance the brake spring 82 is supported by the beam 47.

TWith the arrangement shown in Fig. 4, the brake apparatus will not be applied until the tension on the driving cable is relieved, for example, by the breaking thereof, to such an extent that the tension weight V strikes the lever 69 and exerts a downward stress thereon to effect the actuation of the lever 76 and brake shoe 78 against the counter-action of the spring 82. 1t is evident that if the car and load are under-counterbalanced, and the driving cable is broken, the car will immediately begin to fall. Therefore, although the brake apparatus may be applied to any other sheave than the car suspension sheave, it is preferable and safer to apply it to the latter, particularly in the systems illustrated. As before, the brake shoe 78 may be brought into engagement with the suspension cables 15 as well as with the sheave 16, so that slipping between the cables 15 and the sheave 16 is also prevented.

Fig. 6 illustrates a slight modification of Fig. 4 in that the lever 69 is connected by the rope, chain, or other flexible device 84 to the brake lever. This rope is fastened to the end opposite the fulcrum at the point A 7 3 and extends over the sheave 86 suspended from the beam 47, thence over the sheave 85, also connected to the beam 47, and thence to the lever 76 to which it is connected at 79. The lever 76 is provided with a fixed bearing or fulcrurn 75 on the standard 83 which is secured to the beam 47. r1`he spring 82 is mounted on the beam 47 between the standard 83 and the brake shoe 78. New when the tension weight W strikes the lever 69, power is transmitted through the connection 84 to actuate the lever 76 against the spring 82, and thus apply the brake shoe 78 to the suspension sheave 16 to stop and hold the car stationary until the driving apparatus is repaired and the brake apparatus automatically restored to normal position by the release of the tension weight W.

1n Fig. 7 an electric motor M is shown directly connected to the driving sheave S. The driving cable 4 is iixed at the point 3 and extends upwardly over the counterweight sheave 5, downwardly around the driving sheave S, thence up around the overhead sheave 6 mounted on the overhead beam 7, down around the counterweight sheave again, up around the sheave 9 mounted on the beam 7, and finally to the point 10 at the right-hand end of the beam 1.1 which is pivoted at 29 to the link 46 which in turn is pivoted at '14 to the fixed beam 47 in a manner similar to that indicated in Fig. 1. The car suspension cable extends from the counterweight W up around the suspension sheave 16 to the car C. r1`his sheave 16 is mounted on the pivoted beam 11 and is guided to have a vertical movement by the guideway 45, as explained with reference to Fig. 1. An additional lever 11 is pivoted to the lever 11 at 104, one end of this lever being connected at 105 to the brake strap 24', and its other end being connected at 106 to the dash-pot device 107. rllhe other end of the brake strap 24 is connected in this instance at the point 10 to the end of the lever 11 opposite that of its fulcrum point 29. Normally the parts are so adjusted that the brake strap 24 is held out of contact with the sheave 16, but if the tension on the driving cable is sufficiently relieved by the breaking thereof or otherwise, the weight of the car and its load and the counterweight will cause the sheave 16 to travel bodily downwardly. This sheave 16 being mounted on the lever 11 at a point other than the pivotal point 104, and in this instance to the right thereof, as viewed in Fig. 7, the downward movement of said sheave will cause the levers 11 and 11 to close together shear fashion, the downward movement of the point 106 being resisted by the dash-pot 107. This is more clearly seen if it be considered that the driving cable is entirely severed at any portion thereof so that the car and its load together with the counterweight will immediately cause the sheave 16 to drop bodily. 1n such a case, if no safety device were provided and the car were not exactly counterbalanced, it would travel upwardly or downwardly, depending on which side of the sheave 16 happened to have the preponderance of weight. The downward movement of the sheave 16 moves the lever 11 on its pivot 29, but this has no effect in applying the brake strap 24 to the sheave 16 as the former moves with the latter. But when the point 104 which must also travel downwardly, operates the lever 11 on the point 106 as a fulcrum, the point 105 must move downwardly with respect to the sheave 16, and thus apply thebralre strap 24 to the sheave 16, and also directly to the suspension cable 15, if desired. r1`he quickness with which the brake should be applied is automatically regulated by the dash-pot. 1f the driving cable 4 is severed so as to tend to permit the car to fall suddenly, the brake will be applied with its maximum strength at first due to the dashpot, and then as the carris slowed down the brake is eased 01T until finally the dash-pot piston reaches the limit of its movement when the bralre apparatus will be applied with a force directly proportional to the weight of the car and its load and the counterweight. The positive limit of the dashpot piston may be at such a point that the sheave 16 will be held stationary in contact with or just above the fixed shoe 34 which is mounted on the fixed beam 47. This shoe 34 is an additionalsafety feature to limit the downward travel of the sheave 16, and it is evident that such a xed shoe as that designated by the reference character 34 may be used in connection with a suspension sheave whether the brake apparatus is used or not. In the latter event the brake shoe 34 may be mounted on springs and closer to the sheave 16 so as not to be rendered ineective by acquired momentum of downward movement of the sheave 16 if the same should become disconnected and tend to fall.

Fig. 8. illustrates a modiiication of the brake apparatus shown in Fig. 1 but applied to the elevator system shown in Fig. 2, except that the uppermost sheave has no attachments for limiting positively its oscillating movement. Toward the left from the hanger 37 extends a bracket 36 to afford a pivotal point 2S for the brake strap 24". The lower end of the brake strap is connected at 105 to the brake lever 11, the other end of which is connected at 106 to the dashpot device 107. The hanger or yoke 37 is preferably limited to a vertical movement in the guideway 45 extending upwardly from the fixed beam 47. At an intermediate point on the brake lever 11 is pivoted the brake shoe 21 which is associated with the suspension sheave 16. From this pivotal point extend laterally the pins 108 into slots 20 in the front and back portions of the yoke or hanger 37. Normally the upward pull or tension on the connecting cable 33 is suflicient to cause the lower end of the slot 20 to engage the pin 108 and thus litt the dashpot piston out of its cup or receiver, and at the same time lift the brake strap 24" out of contact with the sheave 16. The parts are also so constructed and arranged that the brake shoe 21 will be normally out of engagement with the sheave 16. 1f, however, the driving cable 4 should break or otherwise become deranged so as to tend to permit the car to Jfall, the sheave 16 will at once strike the brake shoe 21 and rotate the lever 11 about the point 106 as a fulcrum. This will cause a braking action to be applied to the sheave to prevent the same from rotating further, but the application of' the brakes will be cushioned by the dash-pot device. The slot 20 allows relative movement between the sheave 16 and the shoe 21, but as soon as the sheave 16 engages the shoe 21 in its downward movement, the lever 11" will be rotated to firmly apply the brake strap 24 to the sheave16. The dash-pot may be so arranged that it will cushion the fall until the car is almost stopped when the piston will reach the lower limit of its travel, after which the application of the brake will be absolutely positive and he held tight with a force proportional to the load hanging from the sheave 16, for instance, the sum of the car, counterweight and any live load there may be in the car.

Obviously various changes in the details and arrangement of parts may be made by those skilled in the art without departing from the spirit and scope of my invention, and 1 desire, therefore, not to be limited to the precise construction herein disclosed.

That I claim as new and of my own invention is 1. The combination with a driving sheave, of a power-transmitting rope, a hoisting rope, a car suspended from the hoisting rope, and brake apparatus controlled by the tension on one of said ropes and applied directly to said hoisting rope to effect the stopping of the car.

2. The combination with a car supporting cable, of a motor for moving said cable to raise and lower said car, a braking device, and a power transmitting cable operatively connecting said motor with said braking device.

3. The combination with driving apparatus, ot power-transmitting means, a car, a suspended sheave, a hoisting cable passing over said sheave and connecting the car and power-transmitting means, and brake apparatus associated with said sheave and automatically applied thereto and to the hoisting y cable upon derangemcnt of the power-transmitting means.

4. The combination with driving apparatus, of power-transmitting means, a load` carrying device connected to said powertransmitting means, means associated with said power-transmitting means for varying the tension of the latter upon variations of load, and brake apparatus connected to said tension-varying means.

5. The combination with a driving sheave,

of power-transmitting means, a load-carrying device connected to said means, tensionleverage-apparatus for said means, brake mechanism, and means co-acting with said tension-leverage-apparatus for eiecting the operation of said brake-mechanism.

6. The combination with a hoisting instrumentality, comprising a cable and a pulley over which said cable runs, of a sheave secured to one end of said cable, a power imparting sheave distant from the said first sheave,abrake device for said hoisting instrumentality, and a power transmitting cable connecting said sheaves and in operable connection with said braking device.

7. 1n a rope drive elevator, the combination with a driving sheave, of an elevator car, a suspension sheave movable up and down, flexible power-transmitting means, a hoisting cable connecting the car to said power-transmitting means and passing over said suspension sheave, and means for limiting the downward movement of said sheave and effecting braking action thereon.

8. The combination with a rope drive system, of tensioning means therefor, a brake ii-o lever, and a brake connected between said tensioning means and said brake-lever.

9. The combination with a rope drive sy tem, of tensioning means therefor, a dashpot, and brake apparatus connected between said dash-pot and said tensioning means.

l0. ln an elevator, the combination with a sheave, of a lever carrying said sheave, a load-carrying device supported by said lever, and a brake applied to said sheave by the actuation of said leve 1.

ll. ln an elevator, the combination with a sheave, of a pivoted lever supporting said sheave, an additional lever pivoted to said `irst-named lever and having its arms normally set at an angle with the arms of said hist-named lever, a brake associated with said sheave and connected between said levers, and means for effecting the closing together of the arms of said levers and the application of the brake to said sheave upon the movement of the latter as a whole. n

l2. ln an elevator, the combination with a suspended sheave, of a guide for the limiting of the movement of said sheave to a substantially vertical one, brake apparatus associated with said sheave, and means tor applying said brake apparatus upon movement oitl said sheave as a whole beyond a predetermined limit.

13. ln an elevator, the combination with a rotatable sheave having substantially a straight line movement as a whole, ot' a load carrying device normally supported by said sheave, brake apparatus associated with said sheave, and means for applying said brake apparatus upon the bodily movement of said sheave exceeding a predetermined limit.

14. In a frictional driving elevator, the combination with a driving sheave, ot' an elevator car, a car counterweight, power-transmitting ropes or cables associated with the driving sheave, a car suspension sheave, a hoisting rope connecting the car and counterweight and passing over said suspension sheave, a pivoted lever supporting said suspension sheave and connected to the powertransmission ropes to maintain tension therein, a brake connected to said lever and associated with said suspension sheave, and means for actuating said brake to apply the same to said suspension sheave to prevent the car from falling upon the power-transmission ropes becoming broken or otherwise deranged to effect the release of said suspension sheave.

l5. The combination with a car supporting sheave, of a movable support for said sheave, a power driven rope, said sheave being maintained in operative position by the tension in said rope, and braking mechanism operatively related to said sheave.

16. The combination with a hoisting instrumentality, comprising a cable and a pulley over which said cable runs, orp a sheave secured to one end of said cable, imparting sheave distant from the sheave, a braking device for said hoisting instrumentality, and a power transmitting cable connecting said sheaves and in operable connection with said braking device, said braking device being maintained inactive under the normal tension in said cable and released under the predetermined diminution in said tension.

17. The combination with a sheave, of a hoisting rope passing over said sheave, a car suspended from one end ot said rope, a counterweight suspended from the other end thereof, a power driven rope for imparting movement to the system comprising car, counterweight, sheave and hoisting rope, and means controlled by the tension in said power driven rope for retarding the movea power rst said vment of said system.

18. The combination with a sheave, of a hoisting rope passing thereover and having a car and counterweight suspended from opposite ends thereof, a pulley carried by said counter weight, a second sheave carried by a lined member, a flexible driving connection extending between said sheaves, and means for clamping said hoisting rope, said means being held normally inoperative by the tension in said driving connection.

19. The combination with a sheave, of a movable support for said sheave, a power driven rope adapted to maintain said sheave in operative position, a car-supporting cable carried by said sheave, and braking mechanism adapted to engage said car-supporting cable.

20. In an elevator system, the combination with a car, of a hoisting cable therefor, a sheave over which said cable passes, a brake lever pivoted intermediately of its ends, one arm of said brake lever being adapted to engage said sheave, a brake shoe and a yieldable connection between the other arm of said lever and said brake shoe, said brake shoe being adapted to engage the sheave when said lever engages it.

2l. ln an elevator system, the combination with a car, of a hoisting cable therefor, a sheave over which said cable passes, a brake lever pivoted intermediately of its ends, one arm of said brake lever being adapted to engage said sheave, a brake shoe and yieldable means connecting the other arm of said lever to said brake shoe, said brake shoe being adapted to engage the sheave when said lever engages it, and a beam pivotally mounted for supporting said sheave.

22. In an elevator system, the combination with a car, of a hoisting cable therefor, a sheave over which said cable passes, a brake lever pivoted intermediately of its ends, one arm of said brake lever being adapted to engage said sheave, a brake shoe secured to the other arm of said lever, said brake shoe being adapted to engage the sheave when said lever engages it, and a beam pivotally mounted. for supporting said sheave, the pivot of said lever being carried by said beam.

23. n an elevator system, the combination with a car, of a hoisting cable therefor, a sheave over which said cable passes, a brake lever pivoted intermediately of its ends, one

arm of said brake lever being adapted to engage said sheave, a brake shoe secured to the other arm of said lever, said brake shoe being adapted to engage the sheave when said lever engages it, and a beam pivotally Copies of Vthis patent may be obtained for five cents mounted for supporting said sheave, the pivot of said lever being carried by said beam, and means for driving said cable including a power transmititng cable having one end secured to said beam and the other end secured to a fixed support.

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

MlCHAEL E. NEENAN.

Witnesses:

CHAS. M. NIssnN, ERNEST L. GALE, Jr.

each, by addressing the Commissioner of Patents,

Washington, D. C.

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