US2578567A - Handrail for moving stairways - Google Patents

Description

Dec. 11, 1951 Filed March 27, 1950 W. F. MASEK HANDRAIL FOR MOVING STAIRWAYS 2 SHEETSSHEET l INVENTOR. -WALTER F, MASEK AT TOR N EY.

Dec. 11, 1951 w. F. MASEK 2,578,567

HANDRAIL FOR MOVING STAIRWAYS Filed March 27, 1950 2 SZ-IEETSSHEET 2 INVENTORZ WALTER F. MASEK AT TORNEY- Patented Dec. 11,1951

HANDRAIL FOR MOVING STAIRWAYS Walter F. Masek, Richmond, Ind., assignorto Multiscope, Inc., Coifeyville, Kans., a corporation of Kansas Application March 27, 1950, Serial No. 152,030

4 Claims.

This invention relates generally to hand rails for moving Stairways.

In my copending application, Serial No. 663,223, now Patent No. 2,545,741, granted March 20, 1951, there is disclosed a hand rail for a moving stairway, which consists essentially of short lengths of spring-wound wire, mounted upon and operated by a roller chain. The chain is located on the inside of the orbit of the hand rail so that, as the hand rail traverses curves, the adjacent coils of spring spread apart more at the outer radius than at the inner radius. While, in the ordinary situation, a hand rail of this type when traversing a curve is enclosed or concealed so that fingers are not likely to become caught and pinched between adjacent coils of the rail, there are nonetheless many circumstances of installation in which it is preferable to have the hand rail exposed at regions where it is curving.

The object of the present invention, generally stated, is to provide a hand rail for moving stairways, in which the structure responds to movement about a curve in like manner to that in which a coil-spring hand rail responds, but wherein the likelihood of fingers becoming pinched between the coils is practically eliminated.

Other objects will become apparent to those skilled in the art when the following description is read in connection with the accompanying drawings, in which:

Figure 1 is a view in side elevation of a section of hand rail constructed in accordance with the present invention;

Figure 2 is an enlarged detail view of the section embraced by circle A in Figure 1;

Figure 3 is an enlarged detail view of the section embraced by circle B in Figure 1;

Figure 4 is a longitudinal sectional view of the hand rail at the region of mounting the same upon the drive chain;

Figure 5 is an enlarged sectional view of the region embraced by circle C in Figure 4; and

Figure 6 is a sectional view taken along line 6-43 of Figure 1.

In accordance with the presert invention, the hand rail of the moving stairway is mounted upon and driven by a roller chain, as in my patent aforesaid. The exposed or hand-gripping surface of the hand rail is formed of a coiled strip whose exterior is formed on a very long radius so that it is flat or nearly so. The coiled strip constitutes a sheath about a flexible core which is suitably anchored to the driving chain. The present invention is characterized by the further feature that the sheathing strip is formed of a T-section and arranged with reference to the core member so that the stems of the T- sections are received in grooves about the outer periphery of the core. The heads of the T- devoid of inside curves (wherein the hand-grip surface is on a shorter radius than the driving chain), then the strips of sheath may abut each other edgewise (when a given increment is straight). On the other hand, when there are inside curves and the strips of sheath abut each other at the maximum inside curvature, they will be slightly spaced, when straight, and more spaced when on an outside curve.

A particular feature of the invention resides in the selection of materials having different coefficients of friction against human flesh. Thus, where a hand is engaged with a section where there are gaps between adjacent coils of strip, some flesh may touch the core member below and between the same. If, however, the core member be made of rubber (which has a relatively high coefiicient of friction against flesh) and the sheath be made of smooth metal (which has a low coefficient of friction against flesh), flesh in contact with both materials is preferentially moved relative to the sheath. Consequently, relative movement between the sheath and core (as at increments of changing curvature) is not likely to result in pinching of flesh in contact with the rail.

Referring now to the drawings for an illustrative embodiment of the invention, the hand rail is composed of a tubular member 1 formed of rubber or other suitable flexible material capable of being cast or molded. As shown, the tubular member I is formed with a helical groove 2 extending about the exterior thereof. The inte rim of the member I is provided with a helicai groove 3, the position of the groove 3 being such that, as it progresses from end to end of the member I, the flights of the groove 3 lie midway between the flights of groove 2. The flexible members I are provided in short lengths as, for example, five inches, and arranged to be assembled end-to-end to form the hand rail.

The exterior surface of the tubular member I is provided with a metallic sheath consisting of a series of convolutions of T-shaped stock 4, arranged so that the stems of the Ts are received within the grooves 2. As shown in Figures 1, 2, and 4 of the drawings, the T-shaped stock 4 is proportioned with reference to the spacing between the convolutions of groove 2, so that the heads of the T-sections in adjacent convolutions almost touch edgewise. The amount of space 5 between the edges of adjacent convolutions of the sheath depends, as aforesaid, upon the curvatures involved in the orbit of the particular hand rail. In any event, there will be more of the member I exposed at space when a given increment of the rail is traversing an outside curve than when it is traveling rectilinearly or when it is traversing an inside curve. In a case where the orbit of the hand rail is devoid of inside curves, the space 5 may be nil (at an increment which is traveling rectilinearly) On the other hand, where there are inside curves, the space at- 5 will be nil when that increment is traversing the inside curve, and consequently be greaterv when that increment is traveling rectilinearly.

The possibility of pinching flesh prevails only when, due to the changing curvature of the hand rail, the space 5 is reducing. By providing the exposed surface of the strips 4 of rounded but nearly fiat contour, and by forming them of material having a lower coefficient of friction against flesh than that exhibited by the member I, flesh will readily slide over the strips 4 and pinching be avoided.

In the particular embodiment shown in the drawings, the spacing at 5 is sufficient to permit the hand rail to traverse reasonable inside, as well as outside, curves. The relation of adjacent convolutions of strip 4 to each other and to the flexible core member, when a given increment is in rectilinear travel, is shown in Figure 2; their relation, when the given increment is traversing an outside curve, is shown in Figure 3; and their relation, when traversing an inside curve, is shown in Figure 5.

Prior to assembling the tubular member I with its sheath, long strips of T-shaped stock are helically wound and set to the desired radius, preferably being slightly less than the radius provided by the member I, so that there is an inherent tendency for the metallic strip 4 to contract against, rather than to expand away from, the core I.

As indicated hereinbefore, it is preferable that short units of the core and sheath be formed separately and then connected end-to-end to form a continuous loop of the hand rail. In effecting the junction between the short sections, a ring 6 is provided at each end of the short section and engages with both sections which are thereadjacent. Such a ring may be provided with a helieally extending rib Y, shaped and propertioned to be received within the internal groove 3 of the core members I. In Figure 4, the dotted jine 8 indicates the line of separation between adjacent sections of hand rail, it being observed that the rib l is interlocked with groove 3 of the sections at each side thereof. From the ring 6, a stud 9 extends radially and makes connection with a link of the drive chain It. In the embodiment shown, the connection is effected through a shoe I! having a surface [2 formed to fit the exterior of the sheathing, strips 4 thereadjacent. It is to be noted that the stud 9 is disposed directly in the projection path of the coil of strip from both adjacent sections of hand rail. Consequently, the strip 4 of the left-hand section shown in Figure 4 terminates at the near side of stud 9, while the strip 4' of the right-hand section shown in Figure 4 terminates at the far side or the stud 9.

From the foregoing description, those skilled in the art should readily understand that the sheathed flexible hand rail herein disclosed not only accomplishes its objects, but provides a hand rail whose physical characteristics better meet the needs of the situation than one wherein the hand rail consists of a coil of plain wire of circular section. The strip 4 may be folded from a fiat sheet or extruded in the T-shape shown. In either event, the stems of the T-sections (extending radially) mechanically stiffen the composite structure in a very desirable way without interfering with the flexibility of the structure for accomplishing curves.

While one embodiment of the invention has been disclosed in detail, it is not to be understood that the invention is limited to such details. On the contrary, it is believed that those skilled in the art will modify and adapt the invention to meet the circumstances of various applications without departing from the spirit of the invention, and such is contemplated.

Having thus described the invention, what is claimed and desired to be secured by Letters Patent is:

l. A hand rail for a moving stairway comprising a helically wound T-section strip, and with the stem of the T extending into a centrally located core member.

2. In a hand rail of the character described having an endless chain drive, hand rail sections joined end-to-end to form an endless loop con nected with the chain drive at joints between the sections, said sections having their external surface formed of a succession of adjacent convolutions of T-section strip, and with the stem of the T extending inwardly into acentrally located core member.

3. In a hand rail of the character described having an endless chain drive, hand rail sections joined end-to-end to form an endless loop connected with the chain at joints between the sections, said sections having a flexible core grooved on its exterior, and with rings of T-section metal strip embracing said core with the stem of the T interfitting with the grooved part of the core.

4. A hand rail of the character described having an exposed surface consisting predominantly of a succession of adjacent coaxially arranged convelutions of strip material having a low coefiicient of friction with human flesh, said convolutions being normally spaced so that the space between the peripheral edges of adjacent convolutions is less than the dimension of saidconvolutions lengthwise of the hand rail, a core member of resilient material within said series of convolutions and interlocked therewith, portions of said core member being normally exposed between the peripheral edges of adjacent convolutions and other portions of said core member adjacent said normally exposed portions and normally underlying the peripheral edges of said convolutions being occasionally exposed, said normally exposed portions and said occasionally exposed portions of said core member being of the same radius and located radially within the peripheral edges of said convolutions.

WALTER F. MASEK.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name- Date 669,528 Hutchinson Mar. 12, 1901 899,933 Wheeler Sept. 29, 1908

Images