US1080846A - Safety device for elevators. - Google Patents

Description

H. PHILLIPS.

SAFETY DEVICE PoE ELEVATOES.

APPLIUATION FILED AUG. 19, 1912.

1,080,846. Patented Dec. 9, 1913.

\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\x\\\\\\\\\\ mx\xx\\\\\\ I HARRY PHILLIPS, OF RANDFONTEIN, TRANSVAAL, SOUTH AFRICA.

SAFETY DEVICE FOR ELEVATORS..

Application fledAugust 19, 1912.

Specification of Letters Patent.

Patented Dec. 9, 1.913.

Serial No, 715,778.y

is adapted to come into operation upon fail.-

ure of the normal sustaining'means and pre-- vent the skip or the like from falling to the bottom of the shaft. It is necessary that such catch mechanism should so act that the falling conveyance is brought gradually to rest. Many appliances have been proposed to effect this result, but most of them have acted to stop the conveyance too suddenly or they have been so complicated that it has been difficultto keep them in a state of efficiency, or for -other reasons they havebeen.

unsatisfactory in practical application.

It is the object of the present inventionto provide an apparatus which shall be free from these defects.

lAccording to this invention, failure of the normal sustaining means throws into action mechanism which operates by means of the movement of the falling conveyance to coil up a length of flexible material. A stop is pro-vided to press against the coil so formed and oppose increase in its diameter. The momentum of the conveyance is thus absorbed in overcoming the increasing braking resistance applied to the coil until the conveyance is gradually brought to rest.

One form of the invention is illustrated in the accompanying drawings, in which:

Figure I is a plan View of the apparatus attached to a skip running in a vertical mine shaft; the apparatus being shown in its nonoperative position. Fig. II is a section on line A-A Fig. I, but showing the apparatus in action; and Fig. III shows a modification of a part of the apparatus.

1, 1, are flanged drums, secured to shaft 2, to which drums belts 3 of leather, canvas, steel or other suitable material are so connected as to coil onto them when shaft 2 is revolved. There is also secured to shaft 2 a wheel 4, provided with teeth 5 which are adaptedl toengage wit-'li part of the mine shaft, e. g. guide 6, when the shaft 2 is moved outwardly as described below. Shaft 2 is mounted in slots 7, in a pair of brackets 8, and is constantly pressed away from the center of the skip by springs 9.

1G is the draw-barfor the skip, to the top end-of which the hauling rope 11 is attached. At the opposite end a pin 12 ispassed through the bar at right angles to its length. Pin 12" projects from either side of the bar and engages with slots 13 in brackets 14. Slots 13 are inclined downwardly toward the guide 6. Pivoted freely on pin 12 are the ends of apair of links 15; the opposite ends of which are attached to shaft 2*. The length of links 15 isv such that, when the draw-bar 10 ispulledv upwardly andl pin 12 f' engages the top of slots 1-3, shaft 2 is pulled back against the pressure of the springs 9 and holds wheel 4 out of contact with guide 6L' 16, 1G, are strong projections which' are curved at 1'7 to conform with the peripheries ofcoilson drums 1, and are set to contact with suclr coils. tov prevent. increase inf the diameter of the same.

' 18, 18, are iianged drums freely mounted to revolve on spindle 19. On these drums are stored the belts 3 and the ends of such belts are passed over `projections 1G and attached to drums 1.

The action of the apparatus is as follows: IVith the skip normally suspended from draw-bar 10 the parts of the apparatus assume the position shown in Fig. I, with pin 12 at the top of slots 13 and the links 15 holding shaft 2 against the pressure of springs 9, away from the guide 6. Wheel 4 is out of engagement with guide 6 and belts 3 are coiled on the drums 18. If now for any reason the weight of the skip be removed from the draw-bar 10, for example if the hauling rope 11 becomes broken, the parts of the apparatus will take a position shown in Fig. II. Draw-bar 10 will drop and pin 12 move to the bottom of the slot 14. This will allow the springs 9 to move shaft 2 outwardly from the center of the skip and such movement will bring wheel 4 into contact with guide 6 and the movement of the skip will cause it to revolve. Revolution of wheel 4 causes drums 1 to coil up belts 3. As soon as the coils make contact with projections 16 they act as brakes against revolution of the drums and at the same time wheel I is forced into closer contact-'with guide 6. As the skip continues to descend the coils on drums 1 tend to increase in diameter until the resistance thereby produced is sufficient to overcome the momentum of the falling skip which is brought to rest.

From the above description of the action of the apparatus it will be understood that the time taken to bring the skip to rest will be dependent to a great extent on the thickness of belt 3. In one revolution a. coilof thin steel belting for instance would increase very little and consequently the resistance bet-Ween the coils and projections 16 su'liicient to overcome the momentum of the skip, would be attained much more gradually than if a heavy leather belt was employed.

In Figs. I and II the guides 6 are shown constructed. of channel shaped steel, slotted in an already known manner as clearly illustrated in Fig. II. Teeth 5 engage such slots QO-positively tof revolve wheel A when itis incontact with the guide.

In Fig. III wheel t is modified for use with wooden guides, in this case spikes 21 taking the place of teeth 5.

As illustrated, the apparatus is shown operating on one guide 6 but it will be understood that both guides may be used by duplicating' the apparatus.

A 110061,22 l(Fig. II)) may inclose the top of the apparatus to prevent any debris falling onto it.

'What I claim and desire to secure by Letters Patent is 1. Apparatus for stopping` runaway conveyances for elevators, comprising normal sustaining means and fixed parts such as the shaft guides in which the skip runs, a wheel movable upon failure of the normal sustaining means to engage said fixed parts and to revolve thereon, a drum revolved by said wheel, a belt connected t0 the drum, to be coiled thereon, and means on the skip opposing increase of the diameter of the coil so formed, Said last named means being so positioned as. to cause the wheel to be thrust more closely into contact with the lixed parts as the coil increases in diameter.

2. Apparatus for stopping runaway conveyances for elevators, comprising fixed parts such as the shaft guides in which the skip runs, a. wheel secured to a shaft, a drawbar, links connecting the draw-bar of the skip with said shaft, means tending to force the wheel into contact with said fixed part-sV Copies of this patent may be obtained for ve cents each, by addressing the Commissioner ofatents,

Washington, D. C.

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