US 439191 A
Description (OCR text may contain errors)
S. H. ROPER.
7 FIRE ESCAPE. No. 439,191. Patented Oct. 28. 1890.
UNITED STATES PATENT OFFICE.
SYLVESTER'H. ROPER, OF BOSTON, MASSACHUSETTS.-
SPECIFICATION forming part of Letters Patent No. 439,191, dated October 28, 1890.
Application filed March 26, 1890. Serial No. 345,317. (No model.)
To all whom it may concern.- 7
Be it known that I, SYLVESTER H. ROPER, of Boston, county of Suffolk, and State of Massachusetts,haveinvented an Improvement in Fire-Escapes, of which the following description, in connection with the accompanying drawings,is a specification, like letters on the drawings representing like parts.
My invention is embodied in a fire-escape of that class in which a suspending cord'or band sustaining the person to be lowered unwinds from a reel or drum as the person descends; and the object of the invention is to produce a compact and efficient apparatus in which the speed of descent is automatically regulated without care on the part of the person being lowered.
' The invention is embodied in an apparatus comprising a winding drum or reel upon which the suspending cord or band (herein shown as a steel tape) is wound and a liquid-retarding device controlling the rotation of the said drum, and thus controlling the speed of descent of the person or weight suspended from the cord wound upon the drum. The operation ofv the retarding device in controlling the speed of descent depends upon the resistance of a fluid flowing through a small aperture, and is entirely automatic and capable of preventing too great acceleration of speed with the maximum weight with which the apparatus is to be used, and it is so devised as to offer practically no resistance to the reverse movement of the winding-drum, so that the tape can be quickly wound upon it again to prepare the apparatus for use for a second time if need be. In the construction herein shown the piston or moving part against which the liquid acts to resist and restrain the rotation of the drum has a rotary movement in an annular chamber provided with an abutment, between which and the piston or pistons the liquid is confined, and thus resists movement of said pistons, except as it can flow through from one to the other side thereof. The pistons are hinged or pivoted to enable them to pass the abutment in their rotary movement.
Figure 1 is a side elevation of a fire-escape apparatus embodying this invention; Fig. 2, a front elevation thereof; Fig. 3, a central longitudinal section on line an :0, Fig. 2; Fig. 4, an elevation of the retarding device, as seen with the cover or bonnet of the retarding-cylinder removed; Fig. 5, a sectional detail showing the mode of pivoting the pistons; Fig. 6, a plan view of one of the pistons of the retarding device detached; Fig.7, a sectional detail on line a, Fig. 3; and Fig. 8, a detail to be referred to.
The drawings are made of the actual size of the apparatus, which consists, essentially, of two portions-one having a rotary movement with relation to the other in winding and unwindingthe suspending cord or band.
The stationary portion comprises a shell a, provided with a staple or eye a which may be connected with a piece of wire rope or other suitable suspending device a (see Fig. 1,) having a hook at for engaging with some part of the building from which the person is to be lowered, the said shell a thus remaining practically stationary during the operation of the instrument. 7
The shell or is rigidly connected with a spindle or stud 1), upon which the rotating part of the instrument turns, the said stud I) hav ing connected or made integral with it a portion 0, which forms the innerwall of a cylinder or annular chamber cl, forming part of the retarding device, said centralportion 0 being extended radially outward at one part, as shown at 0 to form an abutment or partition across the annular. chamber d. The entire outer wall and both ends of the cylinder (1 are connected with the winding drum or reel e, upon which the cord or band f is wound, a small portion only of said band being shown in Fig.
3, which is represented as having the band nearly all unwound. As shown in this 1n stance, the winding-drum e and one end e and the outer periphery e of the cylinder d is suspended, and which is rigidly connected with the inner wall of the cylinder, incloses the suspending cord or band f when wound upon the drum 6, and is provided with an opening a in one side, through which the said band passes in winding and unwinding, and it will be seen that with the parts thus far described, if the casing a is held stationary, the spindle 1) forms an axis about which the winding-drum e and outer portion of the cylinder may be turned by drawing upon the baud f or otherwise. In order to regulate the speed at which the said winding-drum can turn and the band can be unwound therefrom, thesaid cylindrical chamber (1 is filled with a liquid, preferably glycerine, and said liquid is made to resist the rotation of the winding-drum and outer part of the cylinder by means of pistons 71, which, as shown in this instance, are hinged at one end in the outer cylinder, while the other end of each bears against the outer surface of the stationary inner wall 0 and abutment-piece 0 as shown, being normally pressed against the same by springs 7L2. By this construction it will be seen that when the outer cylinder tends to rotate in the direction of the arrow, Fig. 4, with relation to the stationary inner portion and abutment 0 0 a portion of the liquid will be confined between the said outer wall of the cylinder, the abutment, and one of the pistons 71, and if the said piston and abutment had an absolutely tight fit the said liquid would absolutely prevent the rotation of the cylinder, and it is only by the gradual escape or leakage of the said liquid from one to the other side of the piston it that rotation of the cylinder is permitted. Such leakage may be, and preferably is, provided for by a sufficient looseness in the fit of the pistons; but in order to indicate more clearly on the drawings the intention of the device the said pistons are shown as provided with a small passage or leak h through which the liquid may flow from one to the other side, or rather by means of which the piston is enabled to travel through the liquiclavhich remains practically stationary in the cylinder. The outer wall of the cylinder is recessed, as shown at 71 to receive the pistons h as they pass the abutment 0 as shown in Fig. 4, the said abutment acting as a cam to carry the pistons h out into their recesses, and they, being thrown inward again by their springs as they pass beyond the abutment, which has a sufficient portion made with a working fit on the inner surface of the outer cylinder, as shown in Fig. 4-, to more than span the length of the recesses 72*, so as to prevent the liquid from passing by the end of the abutment through one of said recesses.
It will be seen that if the winding-drum and outer cylinder were turned in the direction opposite to the arrow, Fig. 4, the liquid would merely be confined between the abutment and the under sides of the pistons h,
and would merely have the resistance of their springs 7L2 to overcome, so that the said pistons would easily rise to pass through the liquid without materially retarding the rotation of the drum, so that the band f can be quickly wound upon the drum 6 when required, although its speed in unwinding is governed by the liquid, and the retarding action is wholly automatic, requiring no attention whatever on the part of the person being lowered. In order to facilitate the winding up of the band upon the drum, the cylinder is provided with a winding crank or handle 7c, pivoted at upon the shank of one of the screws by which the bonnet is fastened to the cylinder and provided with stop-shoulders 76 which engage with a stop-pin k on the cylinder, limiting the movement of the crank relative to the cylinder to one-half a turn, so that the said crank may be turned across the cylinder, as shown in Figs. 1, 2, and 3, when it is not in use, or may be turned half-round, so as to project radially out from the cylinder, as shown in dotted lines, Fig. 2, thereby giving increased leverage for turning the cylinder to wind the band upon the drum. The said handle is is preferably provided with a stud or projection is", (see Figs. land 3,) engaging with a recess on the cylinder shown as formed in the head of one of the fasteningscrews 6 which affords a slight friction or resistance tending to keep the handle in normal position diametrically across the cylinder.
The stationary frame or shell a is rigidly connected with the spindle b, but so as to permit free rotation of the winding-drum on said spindle, except as resisted by the liquid, in the following manner: The end of the said spindle is turned down slightly, so as to form a shoulder 6 and is threaded outside of said shoulder, as shown at 5 to receive a nut 11 by which the face of the shell a is tightly clamped against the said shoulder b and in order to prevent any possibility of the spindle and abutment c from turning with relation to the shell a the said spindle is provided with a pin 6 enteringa suitable notch a in the shell to, as shown in Fig. 8.
The pistons h have their pivoted ends rounded for their entire width to work in correspondingly-munded seats formed at the ends of the recesses 7r, and said pistons are preferably also provided with pintles or trunnions extending laterally from their pivoted ends, as shown at 72*", Figs. 5 and 6, and entering suitable passages in the portions 6 e of the outer cylinder, as shown at 71 Fig. 5, thus securely retaining the said pistons in place when the apparatus is put together.
Any desired number of pistons may be used, the only limit being the capacity of the wall of the cylinder for the recesses with a sufficient space between the said recesses to aiford a barrier against the passage of the liquid when passing over the ends of the abutment; but two of said pistons are sulficient if both work properly, one to be resisted by the liquid while the other is passing over the abutment.
' The suspending band or tape f may be fastened to the winding-drum, as best shown in Figs. 3 and 7, the said drum being recessed for a portion of its width, as shown at e and the said recessed portion being spanned by a pin 6 around which the end of the band is looped, the said loop portion being made slightly narrower than the main portion of the tape, so as to afford a bearing for both ends of the pin a", which preferably screws into the shoulder left at the end of the winding-drum, but is prevented from working out of place by the shell a. By this means of fastening the tape it is free to exten'd out radially when wholly unwound and does not bring any binding strain upon the tape, although the latter will never be wholly unwound in use except when used to lower a person fromthe highest place within the range of the length of the band.
It will be observed that the leverage with which the weight suspended upon the band acts to turn the drum in unwinding diminishes as the band unwinds and decreases in diameter, and consequently the retarding effect increases as the person approaches the ground, and for this reason the capacity of the apparatus can be increased by merely enlarging the diameter of the shell a, so as to contain a greater length of tape, although the size shown will be large enough in most cases.
The entire apparatus is very. compact, all the working parts being inclosed and protected in the strong outer case, which need not be over three inches in diameter, and may be less than two inches in length exclusive of the nut 12 and winding-handle k for a working apparatus capable of lowering three hundred pounds weight without greater acceleration than would be acquired in a descent of two or three feet by the action of gravity alone. The apparatus is thus extremely portable and requires no skill on the part of the user, who merely has to make fast the hook a and properly secures the belt or other sustaining device (not shown) connected with the band f to the person, who may then be permitted to drop without danger.
I claim 1. The combination of the case or shell having a spindle rigidly connected therewith, with a winding drum or reel and cord or band connected thereto, and a cylinder connected with said drum and abutment, and pistons co-opcrating with a liquid in said cylinder to resist and retard the rotation thereof on said spindle, substantially as described.
2. The combination of the case or shell hav ing a spindle rigidly connected therewith, with a winding drum or reel and cord or band connected thereto, and a cylinder connected with said drum and an abutment, and pistons cooperating with a liquid in said cylinder to resist and retard the rotation thereof in one but not in the opposite direction, and a'winding- SYLVESTER I-I. ROPE-R.
Jos. P. LIVERMORE, M. E. HILL.