US1381555A - Safety-catch - Google Patents

Description

F. HUDSON.. SAFETY CATCH. APPLxcATmN FILED1UNE20,19:9

1,381,555. Patented June 14, 1921.

2 SHEETS4-SHEET l. Y

I NN- F. HUDSON.

SAFETY CATCH.

APPLICATION FILED IuNE 2o. I9I9.

fM/'XI W 2/ ggg UNITED STATES PATENT OFFICE.A

FRANK HUDSON, OF NOKOMIS, ILLINOIS.

SAFETY-CATCH.

Y Application :filed June 20, 1919.. Serial No. 305,482.

T o all whom il? may concern Be itl known that I, F RANK HoDsoN, a citizen of they UnitedL States, residing at Nolromis, in the county of Montgomery and State of Illinois, have invented certain new and usefulY Improvements in Safety-Catches, of which the following is-a specification.

This invention relates to an attachment for elevators and has forits' principal object the production of a safety catch or device which is so constructed as to allow the elevator cage to move vertically, either upwardly or downwardly along its guides when in usual operation, although in the event the lifting cablev or chain or other device is accidentally severed or breaks, the device will automatically operate for preventing a fall of the cage.

One practical form of construction and assembly of the present invention will be hereinafter described and is illustrated in the drawings in which:-

Figure 1 is a front elevation of the elevator attachment illustrating the device in USE.

In the preferred embodiment of the pres-V entV invention, about to be specifically described, 5 indicates the parallel vertically extending guidesof an elevator shaft. In considering the present inventionY it should be understood that the device is capable of use upon passenger elevators in buildings or upon freight elevators as well as upon the cages Vused in mine shafts. The bottom 6 of the elevator car has end walls 7bear ing upon the guides 5 and it will be noted that angular brackets 8 are connected to the end walls 7 as shown at 9 and are also connected to the supporting bars 10 which are parallel to each other although spaced apart as shown in Fig. 2. Lifting chains 11 areconnected by links 12 to shafts 13 carried by the bars 10 as shown in Figs. 1 and 2. These chains 11 are also connected to a ring 14 to which thelifting cable 15 is connected. Therefore as the lifting cable 15 is wound upon a drum or pulled, it will be noted the chains ll will lift the elevator. It should be understood that although a specific form is described any particular form or design of cage or car may be provided without departing from the 16 are secured upon the upper ends of the.

walls 12 and are also connected to the brackets 8 as shown in Figs. 1 and 2. Extending parallel to these webs 16 and passing upon the outer side of the guides 5 are cover plates 17. Sector shaped cam blocks 18 are interposed between the webs 16 and plates 17 upon each side of each guide 5 as illustrated clearly in Fig. 3. Retaining elements 19 are passed through the webs 16 and plate 17 as well as through the blocks 18, thus firmly anchoring the blocks in position. The inner edges of the blocks 18 are slanted as shown at 20, thus providing the cam surfaces, which surfaces are near to, although spaced from the side edges of the guides 5.

Operating levers 21 are pivotally mounted upon pins 22, it being noted that the pins 22 are also carried by the webs 16'and plates 17. ThusY the levers 21 are 'pivotally' sup-r ported, it being noted that the inner ends of the levers extend to points contiguous to the guides 5, although the outer ends of these levers extend outwardly beyond the webs and plates for a considerable rdistance as shown in Fig. 2.

JV edges 23 are provided, it being noted that the rear edge of each wedge 23 is slanted as shown at 24 while the forward surface thereof is vertical as shown atk 25.

The upper ends of the wedges 23 are piv- Coiled springs 26 have their lower ends fixed upon the walls 7 or other desired part of the elevator, car, or cage as shown at 27, while the upper ends of the springs are connected by yokes 28 to the outer ends of the levers 21, since the yokes are supported upon transversely extending bolts 29. Accordingly, the resiliency of the coiled springs 26 is at all times exerting a pull upon the outer ends of the levers 21. However, auX- iliary chains 30 are connected by yolces 31 to the bolts 29 carried by the outer ends of the levers 21, while the upper ends of the chains 30 are connected to the ring 14 carried by the lifting cable 15.

When the device is in use and under normal conditions the chains 11, which of course can be cables, are held in a taut condition as they support the weight of the elevator car or cage. Accordingly, as the cable 15 is wound upwardly or unwound to move downwardly, the elevator car or cage may move upwardly and downwardly along the guides 5 in the usual manner. Y

The manner in which the wedges 23 are reinforced by the blocks 18 willlirmly hold the ear or cage against side shifting. Under such conditions the taut condition of the chains 30 will cause the outer ends of the levers 21 to be held in raised conditions, thus causing the wedges to be in a lowered condition as shown in dotted lines in Fig. 2 and illustrated in full lines in Fig. 3.

However, if for any reason the cable 15 is severed or breaks, or the operating mechanism for lifting the elevator car or cage becomes inoperative or broken, any of which VKconditions would ordinarily allow the eleva tor car or cage to fall and the occupants thereof to be injured or freight thereon to be demolished, by use yof the present device such serious objections will be overcome. It will be realized that as soon as the cable 15 becomes inoperative for any reason whatever, the normal pull upon the chains will be released thus causing the same to become slack. Instantaneously with such action the coiled springs 26 will be released and due io their tension will immediately swing the outer ends of the levers 21 downwardly with speed and force which action will shift the wedges 23 upwardly yas hereinbefore enplained. As the wedges ride across the cam faces of the blocks 18 they will .be brought into binding engagement with the guides 5, thus causing the wedges to bind firmly upon the guides and thus limit the fall of the elevator car or cage. It is apparent that in the event there is a heavy load in the car or cage the operation of the device may be rendered more efficient, for under such conditions the weight would tend to move the blocks 18 a slight distance further toward the lower ends of the wedges 23 and thus bind the wedges even in a firmer engagement with the guides 5, whereby the car will be held from falling and as a consequence the occupants thereof or materialcarried thereon will not be injured, as the car will he suspended until the broken cable or other defective portion has been repaired and the car or cage is again lifted, thus causing the levers to retract the wedges from their binding engagement with the guides, whereupon the elevator car or cage will again be used in proper and usual manner.

It will therefore be seen that a very simple and efficient mechanism has been provided, wherein the' safety device is normally held in a set condition, so that in the event the lifting mechanism of the elevator suddenly becomes defective and the car starts to fall, this safety mechanism will automatically operate to grip the usual guides of the elevator shaft `whereupon the movement of the car or cage will be limited and the car or cage will be suspended upon the guides 5 as long as necessary, without danger of injury to the occupants or the material carried thereby.

The foregoing description and the drawings have reference to the preferred embodiment of my invention. It is to be understood, however, that I may make such changes in construction and assembly of parts, materials, dimensions, etc., as mayprove expedient and fall within the scope of the appended claim.

Having thus fully described my invention, what I claim as new and desire to secure by Letters Patent is Y In combination with a guide having an elevator car movable therealong and means for raising and lowering the car, a safety device including a supporting web secured to the car and extendinggacross the inner face ofthe guide, a cover plate extending across the outer face of the guide, cam blocks on opposite sides of the guide andY secured between said web and cover plate, wedges 'disposed between the cam blocks and sides of the guide, a lever pivotally connected to the upper end of each wedge and pivoted between said web and plate, means connecting said levers to said raising and lowering means for normally maintaining saidv wedges inoperative and spring means connected to said levers and said car for movingthe wedges into binding engagement with said guides.

In testimony whereof I aiiix my signature in presence of two witnesses.

FRANK HODSON. lVitnesses Jos-,Erri L. MANNING, J. VVnsLnY RArr.

Images