US2495963A - Rolling door - Google Patents

Description

Jam. M, W50 R. H. GREEGOR ROLLING DOOR 2 Sheets-Sheet 1 Filed March 21, 1946 INVENTQW H. GREEGOW Zia/M RALPH ATTURWEWS Patented Jan. 31, 1950 ROLLING DOOR Ralph H. Greegor, Columbus, Ohio, assignor to The Kinnear Manufacturing 00.,

Columbus,

Ohio, a corporation of Ohio Application March 21, 1946, Serial No. 656,075

2 Claims. (01. 160-235) The present invention relates to metal curtains of the slot type used for rolling overhead doors in large buildings, hangars, garages, etc.

The slat form of rolling door usually comprises a recurring series of sheet metal plates, suitably interlocked or hinged at their longitudinal edges and adapted to roll over manual or power driven drums in order to raise or lower the door. While doors of this character are satisfactory, it has been found that in the case of a door of considerable width, the wind pressure may be so severe as actually to cause a bending effect. This may introduce permanent deformation of the slat or at least strain at the interlocking edges which interferes with the vertical movement of the curtain.

The primary object of the invention is to provide an improved door of the slat type which is strengthened widthwise to withstand transverse stress and yet permitting the door to be rolled upwardly in the usual manner.

Another object is to provide a rolling door of the slat interlocking type with reenforcing elements extending over one or more slats to strengthen the general construction of the door while still permitting the door to coil about an overhead drum or to be received by any other overhead operating mechanism.

These objects are attained in brief by providing slats of rounded shape which terminate in loops which serve as hinges to give ease of articulation in coiling. The opposite loops of one slat are respectively received by the edge loops of the adjacent slats. Rigid plates having a shape conforming to the shape of the curved slats are secured thereto and preferably extend in the vertical direction across the interlocking loops of at least two adjacent slats. The effect of these rigid plates is to form wide slats with a higher crown than the original slats. The member so produced is in efiect a beam of substantial cross sectional dimensions and therefore is much stiffer than the slats were originally. The invention will be better understood when reference is made to the following description and the accompanying drawings, in which:

Figure 1 represents a vertical sectional view of a building wall with an opening therein which is closed by a curtain of the slat type;

Figure 2 is a vertical sectional View of a portion of a curtain, improved in accordance with the present invention;

Figure 3 is a view similar to Figure 2 but showing the application of the reenforcing plates to a larger number of slats than in Figure 2;

Figure 4 is a perspective view of a reenforcing plate of a typical length and as shown is adapted to be secured to two adjacent slats; while Figure 5 is an enlarged perspective view of a portion of an improved rolling door to which the reenforcing plates or strips have been applied.

Referring more particularly to Figures 1, 2 and 4, reference character I represents a vertical wall of a building having an opening 2 and in which the last course of bricks 3 are supported by a heavy I-beam 4. A relatively large curvilinear casing 5 is supported on the wall I in any wellknown and suitable manner, this casing containing a manual or power driven drum for coiling a metal curtain thereon, generally designated at 6. It will be understood that instead of causing the curtain 6 to wrap itself about a coiling mechanism contained in the casing 5, the curtain may be caused to roll over a curved surface within the casing 5 and drawn along a horizontal top support which in the case of a garage may constitute the underside of the second story floor.

An enlarged view of a portion of the improved curtain 6 is shown in Fig. 2. As illustrated, the curtain may comprise a plurality of slats made preferably of steel, aluminum or copper and out of sheet metal. Each slat is preferably provided with a relatively wide curved portion, indicated at l, and a narrow curved portion, indicated at 8, reversely arranged. These curved portions terminate in oppositely directed loops 9, it. Thus, each slat section is provided with reverse curves which constitute a good watershed since the outermost portions of the convex surfaces tend to protect the inwardly projecting or concave portions of each slat. The curved sections are so designed as to distribute metal on both sides of the vertical axis sufficiently equal to provide the same horizontal resistance to forces from either side. The particular effect of this section permits the slat to slightly open up or flatten when resisting horizontal forces and this effect allows additional resiliency, providing a strong but flexible curtain with slats that are difficult to cripple.

The loop 9 is made preferably of smaller diametralsize than the loop In in order that the latter may slidably receive the smaller loop of the lower adjacent slat. The metal at each of the loops continues in the circular direction a suflicient distance to cause the loops to interlock in the vertical direction of the curtain. It is apparent that these slat portions of the curtain are assembled by sliding endwise the loop end of one 3 slat into the loop of the adjacent slat. These slats are usually fairly narrow, perhaps on the order of 2 or less so that the rigidity of each slat does not materially interfere with the facility with which the curtain is caused to coil about the overhead drum.

Curtains of this general type have been found to be satisfactory in operation but when the curtain is of considerable width, for example, in the case of a hangar door located in an exposed posi tion, it has been found that in the case of extremely heavy wind, the resulting pressures are so great as to cause strains at the interlocking loops and in extreme cases, the curtain may bend or buckle at the middle. In accordance with the present invention, I provide a number of rigid plates or strips of metal preferably shaped equidistantly apart across the entire widthof the curtain and extendin over one or more loop joints to serve as a reenforcement. In Fig. 2, the reenforcing plate is indicated at It and has a configuration which closely approximates the shape of the reverse curved slats except that a relatively straight portion [2 is provided directly opposite the loops 9, it. The length of each plate as measured in the vertical direction will depend on the width of the slats and in case it is desired that the length of the plate shall be limited to the span of two slats, the plate will preferably terminate at a position where the loops 9, iii

begin. The width of each strip, as measured horizontally of the curtain, will depend on the amount of reenforcement necessary and also on the width of the curtain which determines the number of plates applied per foot of width of the curtain. For a curtain of typical size and exposed to average wind conditions, plates of approximately 4" width and spaced approximately 1 /2 feet apart over the entire width of the curtain will be found to give satisfactory results.

The plates I! may be made of sheet steel and have considerably greater thickness than the thickness of the slats. They are secured to the slats in any suitable manner such as by-spotwelding but preferably by the use of fiat-headed rivets, indicated at iii. For this purpose, the plates are initially provided with holes M "and these holes are so positioned that they come within the relatively flat portion of the plates which lends ease pf drilling openings in the relatively flat portions of the slats. A perspective view of a double-slat portion of the improved curtain which has in effect been formed into a'ri'gid single slat by the use of the plates H is shown Figure 5. The over-all width of the double-unit slat is still sufficiently small as not to interfere greatly with the coiling effect on the overhead drum. When a curtain has been provided with the plates H, as described hereinbefore. it has been found that the strengthening or reenfo'rcing effect offered by these plates in the widthwise direction is phenomenally great so that the curtain offers a strong resistance to any horizontal force, particularly at the middle of a wide curtain and without reducing in any appreciable degree the bendability of the curtain at the overhead elevating mechanism.

The combined slat sections can be so assembled in a curtain, that the curtain is made up entirely of these sections, or these built-up sections can be used intermittently to reenforce a rolling door. This increased crown effect can be readily 'discerned from the showing in Figure 2 in which the intermediate joints 9 and Ill have been moved considerably away from the line connecting the uppermost joint 9 and the lowermost joint 10 so that the crown in a given size and shape of door may be approximately 1%" instead of which it would have been without the plates 12. This could be increased or decreased as desired. Thus, the sections formed of two or more slats which are joined together by the plates 42 are provided with a larger. moment of inertia and thereby offer increased resistance to deflection.

In an extreme case as when unusual reenforcement becomes necessary, the plates I! may be of such length as to embrace three adjacent slats or even more when desired. A portion of a curtain which has been constructed in this man ner is shown in Figure 3 and it will be noted that the plate H has greater length than in the case of Figure 2 so as to terminate at the loop portions 9, IQ of each group of three slats. While it is apparent that the relatively long plate II will serve to reduce the cendability of the curtain shown in Figure 3 greater than in the case of that illustrated in Figure 2, nevertheless a certain and useful amount of articulation is retained at the upper and lower free loops which will still permit the curtain to coil about a drum. In the event that the curtain is elevated to its full open position while remaining in avertical direction, it is' apparent thatthe rigid plate ll may extend over as many slats as desired in order to increase the reenforcing effect which opposes transverse stresses caused by gusts of wind, etc.

From the foregoing, it is evident that I have disclosed an improved form of a rolling slat cur-' tain which can be readily and inexpensively reenforced against strong transverse pressures com-- ing from one side or the opposite side of the curtain while retaining the curved slat construction which offers unusual benefits from the standpoint of watershed. The slats, at the point of articula tion are securelyinterlocked in the vertical direction sothat even in the case of curtains of considerable height each slat remains securely in position without interfering with the articulation function. 4

It will be understood that various modifications and arrangements in structure could be made without departing from the spirit of my inven' tion and, accordingly, I desire to comprehend such modifications and substitutions of equiva lents as may be considered to come within the scope of the appended claims.

Having thus fully described my invention, what I claim as new and desire to secure by Letters Patent is: l

1. .An articulated metal curtain formed of crowned metal slats terminating at the edges in loop portions, the loops of one slat being adapted to respectively engage the loops the adjacent slats to form slidable joints. and. a plurality of rigid reenforcing plates extending across at least two of the adjacent slats as far as the oppositely disposed loops of the double-slat unit in order to fix the two slats rigidly with respect to one another at an angle which substantially increases the crown thereof to impact resistance to the curtain with respect to transverse width pressure, said plates being spaced along the lengths of said slats.

2. A curtain formed of metal slats having a reversed curved configuration widthwise of each slat and terminating along each edge in a substantially complete loop portion, the loop portions of each slat being adapted slidably to be re-' ceived by the'loop portions of the adjacent slats to form articulated joints between the slats, and REFERENCES CITED a reenforcing metal strip having the same con- Th f n I f n f d th figuration lengthwise as the Widthwise configufile i fi ere 088 are 0 recor m e ration of the adjacent slats secured to said slats p in order to strengthen the curtain as a whole 5 UNITED STATES PATENTS against external forces applied to the middle of N 1 the curtain, said strips being formed to hold said gg b i' b slats convex outwardly of the curtain to provide 1 367240 1921 a summing beam efiect- 114371947 Probert Dec. 5, 1922 1,579,915 Cornell Apr. 6, 1926 RALPH H-GREEGOR' 2,204,363 Jenkins June 11,1940

Images