US 2784780 A
Description (OCR text may contain errors)
March 12, 1957 c. s. EVANS 2,784,780
VENETIAN BLIND STRUCTURE Filed octl 14, 1952 /NVE/VTOR ...u ...m-.....- @'n'nnw United States Patent i VENETIAN BLIND STRUCTURE Charles S. Evans, Atherton, Calif.
Application October 14, 1952, Serial No. 314,680 4 claims. (C1. 16o- 118) My invention relates to Venetian blinds and particularly to means for demountably connecting the slats to the ladder tape; and this application is a continuation-impart of my copending application Serial No. 782,110 tiled October 25 1947, later abandoned.
One of the objects of the invention is the provision of such a connecting means formed 4from a single stn'p and in which the severable connecting part which is integral with .the remainder of the device, constitutes `the resilient stud part of a snap fastener. Because the connecting means yor connector includes a fastener element, and also is adapted for movement with the connected slat lengthwise of the supporting rungs, it is convenient to refer to it as a slide-fastener.
Another object of the invention is the provision of readily engageable and disengageable fastener elements Iwhich w-ill not rotate relative to each other.
The invention possesses other objects, some of which with the foregoing will be set forth in the following description wherein are explained those forms of the invention which have been selected for illustration in the drawings. In `said drawings, illustrative forms of the invention are shown, but it is to be understood that it is not limited to those forms, since the invention as set forth in the claims may be embodied in other for-ms.`
Referring to the drawings:
=Figfl is .a perspective view showing the connecting means or slide lfastener of my invention.`
Fig. 2 is a plan view of the slide fastener shown in Fig. l.
Fig. 3 is an elevation of the slide fastener shown in Fig. l.
. Fig. 4 is a bottom View of the slide fastener shown in Fig. 1.
Fig. 5 is a horizontal sectional view of a portion of a Venetian blind, taken immediately above a short piece of slat lying in horizontal position in a twin rung ladder tape. Parts of the supporting pair of rungs, and the slide fastener between them and the slat, are shown in hidden lines.
Fig. 6 is a vertical sectional view of a portion of ladder tape and slat, with my slide fastener between them. The plane of section is indicated by the line 6 6 yof Fig. 5.
lFig. 7 is a vert-ical section through the stud portion of my slide fastener, and through the adjacent portion of an engaged slat. The plane of section is indicated by the line 7-7 of Fig. 2.
Fig. 8 'is a perspective view of a modiiied form of my slide fastener.
Fig. 9 is a perspective view of another embodiment of my invention.v
Fig. 10 is a vertical sectional view of the latch part of the slide fastener shown in Fig. 9. The plane lof section is indicated by the line 10--10 of Fig. 9.
IThe scale at which Figs. 1 to 4 inclusive :and 8 to 10 inclusive are draw-n is approximately three times the actual size. The scale for Figs. 5 and 6 is approximately Patented Mar. 12, 1957 YVice 2 one and one-half times actual size; and the scale of Fig. 7 is approximately six times actual size.
.This invention has :to do with Venetian blinds, but chiefly concerns a lconnecting means embodying `snap fastener elements for securing the slats in the ladder tape. Venetian blind ladder tapes are mainly of two broad types, woven or warp thread rungs arranged in single staggered formation between vertical webs, and double or twin rungs lying in the same horizontal plane.
The slide fasteners shown in Figs. l and 8 are particularly adapted` and are preferred for use in the twin rung type of ladder tapei The slide fastener shown in Fig. 9 may also be used with the twin rung ladder tape, but is especially adapted to be used with the conventional staggered rung ladder tape.
Referring first to Fig. 5, the two vertical webs 2 and 3 of the ladder tape are connected at equal intervals vertically by the twin rungs 4 .and S. A slat 7, preferably of thin metal is supported on each pair of tungs, it being understood of course that a similar ladder tape assembly is provided at each side of the blind so that the slats are supported adjacent each end. With blinds having long slats, one or more intermediate ladder tapes are used. The distance between the vertical Webs 2 and 3 is greater than thel Width of the slat to give ample space for the lifting cord 8 which extends along the inside of one of the webs between it and the slats. Where but two lifting 4cords are used, they are placed on opposite sides o-f the slats, one at each end of the slats.
Meansl are provided for releasably securing each slat to at least yone pair of its supporting rungs, so that accidental release and longitudinal movement of the slat is prevented, but free lateral movement of the Slat is insured in automatic adjustment of its position during operati-on of ythe blind.
But one connection between a slat and the rungs is needed to retain the slat` in perfect alignment; and lthis is provided bythe slide fastener 9, which encloses both rungs 4 and 5 of the pair as shown in vertical section in Fig. 6. Thus slides appear only under alternate slats on one end of the blind and under Athe intervening slats at the other end.
The slide fastener 9 while formed of a single piece is comprised of two main partsthe fastener element which engages resiliently and releasably in the complementary fastener element of the slat; and the main body portion, which furnishes a free slideway for and encloses the twin rungs which support it and the connected slat.
`Because it is very desirable to have Lthe slats even and smooth to facilitate taking them iout of the ladder tapes and putting them back; as well as to facilitate cleaning them While disassembled, the eye or socket member of the fastener combination is preferably placed in the slat; and in this case is merely a small generally rectangular hole 12 with rounded corners and punched in the long center line of the slat, preferably ywhen it is eut to length. While one such hole is all that is needed, it is preferred to punch a hole at `each end of the slat so that it is reversible as well as removable. The companion member .of the fastener comprises a resilient stud formed integrally with the main body of the slide. Fig. 3 :shows a side v-iew of the closed slide fastener, the dotted lines indicating the position of the lower arm when the slide is open and before it is closed over the rungs.
fThe slide fastener is formed in suitable dies from a thin strip of hard brass, and comprises an upper arm `11i and lowerarm 14 connected at one end by the.` bend 16. The free ends of the arms are provided with curved, inte-rlittin g and complementary parts 17 and 18 and the proportions and shapes and tensions are such that while the slide fastener comes from the dies with the lower arm open 3 the and linger closes the lower arm, seating the curved end 18 within the curved end 17 of the upper arm, in which position the strip forms a flattened loop with ends held resiliently togetherso tightly that they are not readily `released except with the aid of a small pry, such as' a thumb nail or dime.
It will be noted that the lower arm 14 in the open position is slightly curved away from the upper'arm. The resilience of the metal, the proportions of the bend 16, the curvature of the arm, the width, length and position of the hole 21 in the lower arm, and the curvature and proportions of the arm ends 17 and 18, are factors which must be carefully balanced to secure a slide which may be easily closed over the rungs and will retain its closed position against any accidental force, but which is readily pried open without injury if opening is necessary.
The upper arm 13 is preferably stilfened by shallow internal beads 22 extending parallel to its long edges. The arm is formed with a wide depressed or reentrant portion 23 extending laterally across the central part of the arm. From the central portion of the depressed part rises the fastener element or stud, adapted to engage the hole or eye 12 in the slat. This stud is formed integrally with the arm proper, by forcing up a deep bead extending across the arm in three aligned sections; the central section 24 being separated from the outside sections 26 by slits 27 which extend clear around the bead and into the depressed portions 23,- so that the central section is given all desirable exibility and resilience.
As best shown in Fig. 7, the middle section of the bead is expanded very slightly laterally beyond the two end sections and constitutes a resiliently flexible loop readily engageable in the eye and which is resiliently retained therein; while the end sections merely snugly fit the eye and do the work of the stud in preventing relative lateralmovement between the parts and in protecting the frailer and more flexible section of the stud from lateral stresses. Because of the rectangular shape of the three-part stud, the slide is lockedA against turning when the slat is engaged. This constitutes an advantage over a slide which embodies a round stud which permits turning, since the most favorable position of the slide with relation toy the rungs is assured at all times. Another advantage of the integral structure of slide and stud is its cheapness` of construction. As shown in Fig. 5, the eye or socket member 12 of the fastener is somewhat longer than the overall length of the stud member. This greater length, coupled with the rounded top` of the stud, facilitates engagement of the studin the eye without hunting'for it.
The reason for havingl a depressed portion from which l to raise the stud-bead is to have a suicient length of stud for flexibility without making overall height too great, it being highly desirable to have as short a portion of the stud as possible extending beyond the upper face of the slat. Flexibility of the central stud section is increased by extending the slots 27 into the depressed portions. When so made, the stud enters theeyein the slat only enough for the bulge in the central portion 24' to take its maximum hold on the edges of the hole. So engaged, as shown in Fig. 7, the stud extends the minimum distance beyond the surface of the slat, and in-consequence presents'less'chance for rubbing against the next above slat.
It will be noted that the studsections in Fig. 2 extend laterally clear across the arm. In some cases it may be desirable to use a wider armwhile retaining a relatively shorter stud section. Such a structure isv` shown in Figure 8. The formation of the three-section stud is the same as in Fig. 2 except that the beads maybe omitted, but there is aportion 31'of metal at each endV of the stud'that must be condensed or shortened to an overall length'equal to the width of thel stud sections.
This is effected by crimping asv shown, the corrugatiorisy being-esutiicient in number and depth to use up'- the excess CJI afstgk; .Iath ses@ infernal ,Stiffening beads 32 extend across the crimped parts and well into the body on each side.
In the slide fasteners of Figs. l and 8 it is desirable to have their inside length a small amount less than the over-all width of the supporting twin rungs, so that the outer edegs of the rungs are drawn together a trifle out of parallelism as shown in Figure 5. This helps materially in maintaining a desired longitudinal alignment of the ends of the assembled slats, since it constitutes an angular guy from each edge of each vertical web to slide and stud.
The importance of the rectangular stud and eye connection between slat and tape lies in the fact that such connection prevents turning movement of the slide on the Slat, so that when the slat shifts from side to side in the operation of the blind, there is no tendency of the slide to bind on the rung. Instead, the rungs move freely and smoothly through the freeways presented by the slide. Furthermore, the rectangular stud and eye insure this favorable position of the slide o n the slat from the moment of connection, since engagement in any other position is impossible.
In Fig. 9, I have shown a modified form of my invention which is useful both with twin rung Aladder tape and the staggered single rung ladder tape. In this adaptation ofv my invention, the non-rotatable releasable connection between the slat and rungs is of particular importance because of the oifset relation of the rung slideway and the stud, and the fact that any contact of the slide and rung, as the slat moves during operation of the blind, tends to swing the slide around kinto frictionl engagement with the rung, when only free movement is desired. The stud structure isY the same as that previously explained, except that if desired the central section may be separated by the ,slit 36 at'its upper end, leaving two prongs or fingers 37 and 38 between the outer sections'39. The prongs are bulged out slightly to make resilient engagement with the sides of the hole asshown in Fig. 7. By splitting the middle section of the stud the range of lateral movement across the prongs maybe increased with an easier or softer resilience, even with a heavier gauge of metal.
Asin the slide shown in Fig. 1, the stud member of the fastener is designed to lie centered in the central vertical plane intersecting both Vertical webs when assembled in the ladder tape with the rung engaged in the slideway 41. Since the eye member of the fastener in all the slats of the same blind is the same distance from the end ofl the slat, it is immaterial in assembling the slats in the two ladder tapes of a blind, which one of adjacent` staggered rungs 'receives the slide so long asy the end opposite the freeway is directed toward the central plane of the ladder tape.
The slide fasteners illustrated in Fig. 9 is stamped from a single strip of thin metal, the lower arm 42 curving A I down and across under the stud from the narrow shoulder 43'formed at the studs base. Thefreeend of the lower arm terminates in a sharply turned lip 44 from the central part of which a short tab 46 projects at a small downwardly turned angle. .Like the slide of Fig. l, and for the same reason, the stud structure rises from a depressediarea 47, somewhat below the level of the upper' arm4 48.
The slide fastener comes fromthe die Lwith the lower arm' curving downwardly as shown by the dottedlines of Fig. l0. When the arms are pressed together around the rung, thetab 46 lirst engages the downturne`d`1lipL49 at the end of the upper arm 43. Continued'pressure tlexes'thestructure4 sufficiently to seat the tab in theslot Stl'to* lock the arms together permanently as shown in Fig. 10.
When the slat 51' is laid over the slide and the stud seated' in the eye, the lower surface of the slat engages the vshoulder 43 and the upper face of the upper arm 48.
With disengagement of the slat, the slide hangs from the rung until the slat is returned to place and the fastener elements once more engaged.
In order to avoid lengthwise movement of the slat in the ladder tape, the slideway 41 is closed along both sides to limit movement of the slide laterally of the rung. This is accomplished on one side by the engaged lips 44 and 49. On the opposite side, the tongue 52, struck from the central portion of the upper arm extends downwardly and forwardly away from the stud into the relatively larger aperture 53, which is formed in the lower arm to adjust resilience as already explained in connection with the lower arm 14 of Fig. 4.
When the open slide is to be applied to the rung, it is pushed against the rung from the inside of the ladder tape. By so doing, the rung is readily gathered up in the corner between the tongue and underside of the upper arm, so that as the tab 46 snaps into its seat, the rung is not pinched. Since the edges of the aperture 53 are well spaced from the end of the tongue, the rung cannot be caught under the tongue, even if not gathered within the hook. These details while intrinsically small are of great importance in permitting fast assembly of the slide on the ladder tape and therefore savings in costs of manufacture.
1. In a Venetian blind having a ladder tape with rungs and slats having rectangular holes therein, a fastener for each slat and comprising a flattened loop for slidably en closing a rung, said loop having a reentrant portion, and a deep bead constituting a rectangular stud comprising three separated and aligned looped sections for engaging non-rotatably in the slat hole and extending integrally from the reentrant portion of the loop, the central section only of the bead resiliently engaging opposite sides of the hole.
2. A fastener stud for resiliently engaging a generally rectangular eye, comprising a plate, a deep bead extending integrally from the plate and of length and width to engage non-rotatably in the eye, said bead being divided lengthwise into three looped sections separate throughout i the height and width of the bead and each end section being engageable in the eye in a merely snug t and the central section in that portion remote from the plate being spread laterally of the bead to resiliently engage opposite sides of the eye. Y
3. A fastener for securing a Venetian blind slat having a rectangular hole therein adjacent to the supporting rung of the ladder tape, comprising a ilattened loop to enclose the rung, one attened side of the loop having a reentrant portion, a bead constituting a rectangular stud extending integrally from the reentrant portion of the loop in aligned looped sections to engage the hole in the slat, one of said sections engaging the hole in a snug t and a section engaging the hole resiliently', and both Hattened sides terminating in mutually interlockable resilient means for holding the loop closed.
4. The combination according to claim 3 in which the resiliently engaging section of the bead is separated across its top portion into two opposed resilient prongs.
References Cited in the tile of this patent UNITED STATES PATENTS 608,495 Walter Aug. 2, 1898 1,372,299 King Mar. 22, 1921 1,563,302 Tost Nov. 24, 1925 2,031,981 Runge Feb. 25, 1936 2,154,712 Van Uum Apr. 18, 1939 2,200,349 Walker May 14, 1940 2,223,622 Kost Dec. 3, 1940 2,306,460 Meyer Dec. 29, 1942 2,311,716 B. Walker Feb. 23, 1943 2,317,660 Williams Apr. 27, 1943 2,381,060 Kahn Aug. 7, 1945 2,455,135 Nelson Nov. 30, 1948 2,533,298 C. D. Walker Dec. 12, 1950 FOREIGN PATENTS 24,168 Great Britain 1897 7,256 Great VBritain 1910