US 516117 A
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' Unirse S'rn'rns la'rnnrr @retient SYLVESTER H. ROPER, OF BOSTON, MASSACHUSETTS.
SPECIFICATION forming part of Letters Patent No. 516,117, dated March 6, 1894. Application filed lcy 19, 1893. Serial Noi 474,765. (No model.)
To all whom it may concern.'
Be it known that i, SYLvnsrEn H. Borna, of Boston, in the county of Suffolk and State of Massachusetts, have invented certain new and useful Improvements in Fire-Escapes,of which the following is a specification.
This invention relates to that class of fireescapes in which an object or person is lowered by means of a line which unwinds from a reel or drum. An apparatus embodying these features is shown in my former patent, No. 439,191, granted October 28, 1890, and means are there illustrated whereby a suitable iiuid may be employed as a retardiug agent to prevent too rapid rotation of the reel or drum in unwinding.
The object of the present invention is to provide improved means for securing this re tarding effect through the agency of a huid.
To this end, the invention may be said to consistin combining with a spindle and drum, an eccentric chamber arranged to rotate with said drum, a circular block in said chamber and fast with the spindle, said block being concentric with the latter and having a plurality of radial slide-ways, a separate movable Wall in each radial slide-way, and means for projecting and retracting said movable walls.
The invention further consists in certain novel features ot construction and combinations of parts hereinafter described and claimed.
The accompanying drawings illustrate a construction by which the invention may be carried out.
Figure 1 shows a side elevation of au apparatos constructed in accordance with my invention, the cover ot' the eccentric chamber being removed. Fig. 2 shows a view ot' the inner side of the said cover. Fig. 3 shows a section on line 3-3 of Fig. 1. Fig. 4 showsa detail of one of the movable walls or pistons.
The same letters of reference indicate the same parts in all the figures.
In the drawings: the letter a designates a casing, which is adapted to be suspended from a suitable fixed support, as a sill, by means of a chain c', attached to it and having a hook o2 at its free end. Thus the said casing will be held practically stationary. A
spindle b extends through the said casing, and a drum or reel h is mounted on said spindie. A line, preferabl7 a steel tape c, is attached to the drum and winds on the same within the casing, the latter having an opening in one side, through which the tape issues from the case. A circular chamber d projects at one side of the casing a, and is fast with the drum b', and is preferably formed integral with a plate c3, constituting one side of the casing a. The chamber d is eccentric with respect to the drum and spindle. A circular block e has position Within the said casing d, and is fast with the spindle, being preferably formed integral therewith, and is concentric with said spindle, its periphery being in contact with 0r in very close proximity to the inside wall of the chamber d, so that a crescent-shaped space exists at all times within the said chamber. The circular block c is formed with a plurality of radial slide ways o, in the present instance six, and six separate Walls or pistons o', in the form of plates, are employed, one engaging each radial slide-way. The inner wall of the chamber d is a true circle, and means are employed to keep each piston in Contact with said wall or in very close proximity thereto, such means therefore causing the projection and vibration of the pistons in the slide-Ways ot the circular block. The means here shown for accomplishing this result are as follows: Each piston is provided with a projection o2, and in the cover oc5 ot' the chamber a circular groove o4 is formed, and all the projections engage this groove. The groove is concentric with the inside wall of the chamber, and, as the chamber revolves, the pistons will be proj ected and retracted.
The chamber d is filled with a fluid, preferably glycerine on account of its density, and4 the operation is as follows: The person or ebject to be lowered is attached to the tape c, and the descent of the same revolves the drum. Said drum being fast with the chamber d, the latter is also revolved, and the point of contact of its inner wall with the block travels around the latter, and the pistons o consecutively present barriers to the fluid confined between them and such point of contact, so that resistance is created to the IOC,
rotation of the drum, and a comparatively heavy body may be lowered with safety. The confined linid can only escape by way of the ends of the piston or between the block and inner Wall of the chamber, and the construction at these points is so great as to yproduce the desired resistance. The ends of the pistons are kept in uniform relation with the wall of the chamber, by reason of the engagement of the projections on the pistons in the groove in the chamber cover. By reason of the radial pistons being all separate, the ii1- ner wall of the chamber may be a true circle, for there may exist a greater distance between the ends ot two pistons in diametrical alignment at one time than at another.
Provision is made for re-winding the tape while the resistance is dormant, as follows: The spindle projects from the case a, as at a4, and a ratchet h is axed to it inthe present instance byflattening two sides of the spindle and correspondingly shaping the opening in the ratchet which receives the spindle, and by screwing a nut h on the end of the spindle, which is threaded for the purpose, and clamping the ratchet between it and a shoulder h2 of the spindle. The ratchet Works close to the case, and a pawl hais pivoted to the latter and pressed into engagement with the ratchet by a spring h4. The direction of rotation of the drum during the unwinding of the tapey is such that the pawl h3 forms a stop, which prevents rotation of the ratchet and conse-4 quently of the spindle, and hence the drum turns on the spindle and the resistance is active. When the drum is rotated in the reverse direction, the pawl no longer acts as a stop, and the ratchet may freely pass it. Hence the drum and spindle move together, and consequently the circular block and eccentric chamber will both move together, and, as their relation does not then change, no resistance is encountered.
It is evident the construction here shown may be varied without departing from the spirit and scope of the invention.
Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is
l. A fire-escape, comprising in its construction a spindle and support therefor, a drum on said spindle, a line attached to said drum, a chamber fast with the drum and eccentric with respect thereto, a circular block fast with the spindle and inclosed within the said chamber, said block being concentric with the spindle and having a plurality of radial slide-Ways, a separate movable wall or piston in each radial slide-way, and means for projecting and retracting said pistons.
2. A fire-escape, comprising in its construction a spindle and support therefor, a drum on said spindle, a line attached to said drum, a chamber fast with. the drum and eccentric with respect thereto, said chamber having a circular groove in one side, a circular block fast with the spindle and inclosed within said chamber, said block being concentric with the spindle and having a plurality of radial slideways, and a separate piston in each slide-way and havinga projection engaging the circular groove in the chamber.
3. Are-escape, comprising in its construction a spindle and support therefor, a drum on said spindle, a line attached to said drum, a chamber fast with the drum and eccentric with respect thereto, a circular block fast with the spindle and inclosed within the said chamber, said block being concentric with the spindle and having a plurality of radial slide-ways, a separate movable wall or piston in each radial slide-way, means for projecting and retracting said pistons, a ratchet affixed to the spindle, anda pawl on the spindle-support and engaging the ratchet.
In testimony whereof I have signed my naine to this specification, in the presence of two subscribing witnesses, this 12th day of May, A. D. 1893.
SYLVESTER I-l. ROPER.
C. F. BROWN, A. D. HARRISON.