US3126049A - Hollands - Google Patents

Description

March 24, 1964 G. HoLLANDs 3,126,049

CURTAIN PARTITION Filed Jan. 3, 1962 4 Sheets-Sheet 1 MAL INVENTOR. G50/F65 O [/7/1/ 0.5' BY www March 24, 1964 G. HOLLANDS CURTAIN PARTITION 4 Sheets-Sheet 2 Filed Jan. 5, 1962 March 24, 1964 G. HoLLANDs 3,125,049

CURTAIN PARTITION Filed Jan. 5, 1962 4 sheets-sheet 's \1 INVEN TOR.

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United States Patent O 3,126,049 CURTAIN PARTITION George Hollands, Franklin Square, NX., assguor to Torjesen, Inc., New York, N.Y., a corporation of New York Filed `Ian. 3, 1962, Ser. No. 164,092 1 Claim. (Cl. 1150-40) This invention relates to a vertical lift curtain partition, and more particularly to a curtain partition having valuable acoustical properties of sound transmission loss and still more particularly to an operating means for a flexible curtain partition having highly effective acoustical properties of sound transmission loss.

This invention is concerned with and has for its object the provision of a flexible room divider or curtain for the rapid conversion of rooms, such as class rooms, into smaller units, for isolating of larger study groups into smaller units with the great facility of a drop curtain, while achieving a sound transmission loss factor of high magnitude, with a minimum loss of space.

The discovery of the acoustic value of limp, flexible, lead or like heavy metal filled sheets or fabrics to provide a material which has a high sound transmission loss number or effective airborne sound transmission loss, in accordance with the ASTM designation E90-61T, and the American Standards Association designation Z24.19- 1957 has created problems occasioned particularly by the relative weight or density of such sheeting in relation to high flexibility, to tend to discourage its use where frequent conversion of rooms, as in mobile curtain partitioning, is desirable. With such a high degree of flexibility almost to a fiaccid state, as evident by a Youngs modulus of elasticity of 2000 pounds per square inch and a relatively high weight factor of one-half to three pounds per square foot for sheeting of .025 to .125 thickness, an instant curtain partition of a vinyl resin, lead impregnated sheet of the sound transmission class numbers from 18 to 34 introduces problems sufiicient to discourage its use, despite its said attractive acoustical properties.

It is an object of this invention to provide an acoustical curtain with materials of the class described that occupies a minimum area in the form of a vertical litt curtain partition and operating means affording its economical and practical use, despite its great weight and exibility and they normal handling problems engendered by such desirable material.

More specifically, it is an object of this invention to provide a novel vertical lift curtain partition of flexible lead or heavy metal-filled sheeting of the acoustical magnitude described, including operating and assembly means therefor, whereby room conversion may be facilely and quickly effected and full efciency retained in use of the desirable, high sound transmission loss factor.

Still more particularly, it is an object of this invention to provide a novel operating assembly in the form of a vertical lift curtain of highly flexible, lead-filled vinyl resin film of the acoustical magnitude which may permit rapid conversion of large room units into small ones, with separation having high sound transmission loss with minimum space loss.

To attain these objects and such further objects as may appear herein or be hereinafter pointed out, reference is made to the accompanying drawing forming a part hereof, in which FIGURE 1 is an elevation of a curtain in accordance with the invention;

FIGURE 2 is a magnified section on the line 2 2 of FIGURE 1;

FIGURE 2a is a magnified fragmentary section of a detail shown in FIGURE 2;

3,126,049 Patented Mar. 24, 1964 ICC l FIGURE 3 is a magnified section on the line 3-3 of FIGURE 1;

FIGURE 4 is a fragmentary section taken on the line 4 4 of FIGURE 3;

FIGURE 5 is a fragmentary front elevation of the drive assembly;

FIGURE 6 is a plan view of the drive assembly;

FIGURE 7 is a section of another embodiment of the `invention corresponding substantially to the view taken in connection with FIGURE 3;

FIGURE 8 is a fragmentary section of a still further embodiment;

FIGURE 9 is a fragmentary diagrammatic section of a still further embodiment of the invention.

Reference will now be made to the drawings wherein it is disclosed by the invention to provide a room divider curtain 10 suspended from the ceiling 11 and guided along the guides 12, 12 to the floor 13.

The curtain 10 constitutes a material of a high sound transmission loss number or one having an effective air borne sound transmission loss. The preferred material is a sheeting in which a fused vinyl plastic or like high fusion iexible plastic has uniformly distributed in its powdered lead, the composition being modified by a plasticizer to secure a high order of flexibility approaching limpness. When tested in accordance with the ASTM designation E-61T and the American Standards Association designation 22419-1957, sheeting of the thickness of .025 inch to .125 inch, having a relative density of 1/2 to 3 pounds per square foot has a sound transmission class number in the range from 18 to 34.

Specifically, a material which is preferred and which is sold under the trademark LeadX of Bar-Ray Products, Inc., 209 25th Street, Brooklyn, New York, has the following additional constitution:

Vinyl resin, plasticizer, powdered lead or like dense, heavy metal, in the ratio of between 35% to 45% lead equivalent so that a finished sheet of .100 inch thick will have a lead content equivalent to a lead sheet of .035 to .045 inch thick or a finished sheet of .025 inch thick will have a lead equivalent to a lead sheet of .00875 inch to .01125 inch thick, while exhibiting a high degree of flexibility approaching limpness to achieve the sound transmission class number in the range of from 18 to 34 for material 1/2 to 3 pounds per square foot, respectively. Limp flexibility as herein utilized is characterized by a Youngs modulus of elasticity of 1000 to 4000 pounds per square inch.

The specific invention herein lies in the provision of an assembly for achieving `and securing the maximum benefits of this curtain material so that its high sound transmission class number may be more effectively utilized yas a room divider, notwithstanding its extreme weight and high flexibility or limpness, soi :that in partitionfing rooms, such as classrooms, a large study room or hall may be isolated into smaller units, without the space loss of architectural partition structures which normally are employed in building rigid, extensive dividing walls.

In accordance with the invention, -it is preferred to support lfrom the beam 14 extending downwardly from the ceiling 11, spaced brackets 15 by bolts .1(6. The bottom section y17 of each bracket 15 is provided with a base 18, resiliently supported on the springs 119 in relation to the vertical bracket 210 etxending from the 4inner side wall 21. The bracket 20 provides support for end bearings 2.2, 23, between which are journalled the trunnions 24, 25 for the tubular roll 216 upon which the convolutions 27 of the roll up curtain 10 are wound. Trunnion 25 is suitably coupled to a flexible coupling 28 tot a motor drive 2.9 through a brake controlled transmission 30 of a known design which need not be here described in detail.

The convolutions 27 on the roll Z6 are fdesirably rested upon transverse supporting rolls `311, 3d extending from the base 18 at intervals, .depending upon the extensiveness of width .of the curtain, it being understood that for a short lengthA and width of roll body 26 or a large cylindrical `diameter thereof, where little or no sagging tendency may be experienced lfor the weightof curtain, the supporting rolls 31 may be eliminated.

The curtain sheet material lll isv guided over a guide roll 32 so that its lvertical ilig-ht 33 at the point A tangential to the roll 32 in the vertical plane is medially positioned between side wall strips 34, V35 `of the vertical guides 12.

'Ille curtain x10 has its leading edge 36 terminating in a floor engaging loop 37 and isl weighted by the weight.

W, which preferably is capable of conforming to the irregularities of the floor 13'. Preferably -a weighted chain, such `as a tractor link chain which is rigid in one plane and is positioned to be iiexible in the vertical but which retains .a rectilinear outline in the horizontal plane, is included with-in the loop 37.

The vertical ii'ght 33` ofthe curtain between the tangential point A and the midpoint between the strips 3'4, 35 is sealed at the emerging slot 38 and along the entire height of the slot between the strips 34, 35, by spaced seals '59 and 40. These seals, as shown in magnified section in FIGURE 2a, consist of la core lf3y of :a foamed polyurethane within a sleeve 44 of cured vinyl resin film. -Friotional contact is effected to seal the edges 45, 4&5 acoustically, with .a minimum amount of friction adjacent the slot 38, as well as at the periphery defined by the guide strips 12, 12;

While there has been show-n yand described a curtain sheet of fused, leaded vinyl plastic, such as polyurethane, which has the powdered lead uniformly distributed in it, fthe preferred product bei-ng known as LeadX as described, it will be understood that va :foamed sheet of the material, foamed to a range to change the relative thickness Ifrom ls inch to '1/2 inch, may be used to provide a partition having a sound transmission loss factor in the 18 to 34 class number, as well as to lact as an acoustical absorbent partition, provided the foaming treatment also serves toform cell structure with Iinterconnnunicating passages. If the cells are closed, no significant change in the transmission loss factor is secured between a lead impregnated sheet curtain foamed to a thickness 400% of the unfoamed equivale-nt sheet. However, by using foamed material with closed or intercommunicating cells, mechanical sealing :advantages at the edges of the curtain may be obtained to :a degree to eliminate the need for the foarned core seals 34, 35, 39, 40, las well as the high frictional sealing contact which would ordinarily be required between the seals and the curtain whenthe crurtain is extended from the ceiling to the floor, as described.

While there is shown and described a curtain sheet resting transversely upon rolls in the embodiment illustrated in FIGURE 3, it may be found desirable, especmly in shorter widths of curtains and in the interest of minimizing mechanical contact between -the supporting structure and the partitioning curtain, to guide the main roll with minimum contact to the supporting structure. For this purpose, as in the embodiment illustrated in FIG- URE. 7, the main roll of sheet material lll is supported only at. its ends on the tubular core ZM and its leading flight 32a is guided to provide a vertical light 33a from the guide roll a' so that the point of tangency is midway between the strips 34, 3S, as in the prior embodiment. The leading edge of the curtain, adjacent its terminus 36a, has vertically flexible ballast means in the form of a floor engaging loop 37a, as in the prior embodiment, but is additionally stiffened transversely by ialuminum stitfeners 46 immediately above the loop 37a. Within the loop 37a there is a compensating continuous weight which, as in the prior embodiment, constitutes `a flat link chain W, which yields in one plane only, and is positioned to be yielclable only in the vertical plane on the floor.

=For minimizing the transmission of sound through the curtain, the fascia F containing .the roll may be lined with a layer of LeadX flexible lead-plastic sheeting L.

Another 'embodiment of the invention is illustrated in FIGURE 8 wherein the iiexible LeadX curtain 10 is augmented by vertically suspending a supplement curtain 10b in parallelism therewith. These sheets are, for storage, superimposed in rolled up relation on the single core Zeb. The leading edges 3i2c and 32d from each layer are branched :out and guided over guide rolls Ac and Ad, to direct the vertical lights 33C `and 33d in spaced planes from each other through emerging slots 38C and 38d between sealing strips 34e and 35C, and |47, `4-7, respectively, which are arranged in side wall strips of the vertical guides, as in the prior embodiment. The gap between the flights 33C `and 33d need not be great, and lfor an4 ordinary classroom, a gap of four to eight inches may be employed. A gap of seven inches lis preferable andl will largely increase the efficiency of the ii'exible curtain of minimum thickness disclosed herein, to maintain a high sound transmission loss class number, with little structural loss of room area.

While in the prior embodiments illustrated, the idlerv guide roll is placed in a position so that a maximum length of vertical tiight is assured and the great weight of the roll is thereby relieved from the main roll, it is also possible that this guide roll may be placed adjacent the emerging aperture. For this purpose, reference is made to FIGURE 9 where a still further embodiment of the invention is illustrated, insofar as the head section assembly is concerned.

In this embodiment, the flight 32e is guided over the guide roll Ac so that the point of tangency of the vertical flight 33e is midway between the walls defining the emerging slot 38e. In other respects, the vertical flight 33e is guided between sealing strips to seal the horizontal as well as vertical edges of the curtain as it is guided through the emerging slot and through the vertical guides 12, as in4 the prior embodiment.

By the construction described, installations to effect the objective of a iiexible room divider for rapid conversion of rooms into smaller units is achieved, without materially disturbing the wall structure. Thus, assembly rooms of large area may be instantly divided into separate rooms for team teaching. The curtain provides privacy and isolates sound. The mass of the curtain and its density make it possible to utilize the curtain for outlining chalk panels.

Particularly resistant to any swaying action is the embodiment illustrated in FIGURE 8 where both a main and a supplemental curtain are supported from the ceiling in spaced parallel planes.

No special floor tracks are necessary to incorporate the acoustical curtain and by reason of the weighted flex- Y ible loop, compensation is made for irregularities in floor levels and the loop with a flexible liller will conform to such irregularities in the iioor, to seal off light, and sound within the limits of the sound transmission loss factors specilied.

When the curtain is not in use, the roll of acoustical material may be housed in the ceiling enclosures described to occupy a minimum amount of space, regardless'of the height or length of the room to be subidivided. The cur- Y tain lends itself readily to both powerized means of rolling or unrolling and manual control, as no complicated power transmission problems areentailed. Y

Likewise, when the curtain is not in use and is raised adjacent the ceiling, it is out of reach and notV subject to marring or damage, as would be the case with paneled partitions, such as folding doors, or accordion pleatedcurtains, which require side wall space for installation. It will be understood that while there is described and preferred a flexible, pliable, limp sheeting consisting merein which a large mass of curtain would necessarily present a weight problem insofar as elongation of the sheet is concerned once it is hung in position, it may be desirable to reinforce the composition of the plastic material with dispersed bre. However, it will be understood that increasing the weight of the partition will not increase the sound transmission loss factor proportionately to the increased weight, and economy may dictate the employment of the supplemental curtain described in connection with FIGURE 8 in preference to an increase in the weight factor of the sheeting itself.

By the employment of pressure seals at the vertical and horizontal edges of the curtain and by the employment of a floor conforming loop, highly efcient sound sealing is effected in addition to the achievement of high sound transmission loss class numbers by the use of the curtain employed.

Having thus described the invention and illustrated its use, what is claimed as new and is desired to be secured by Letters Patent is:

As a new article, a room partition acoustical curtain comprising a pliable, relatively lirnp, flexible sheet of fused plastic having uniformly distributed therethrough 25 to 45% by volume powdered lead, characterized by a sound transmission class number of from 18 to 34 in sheets of from one half to three pounds per square foot, convoluted in a roll about a core, a horizontally disposed guide roll laterally spaced from said core, said curtain passing over said guide roll and hanging in a vertical plane tangent to a side edge of said guide roll, means for rotating said core about a horizontal axis to raise and lower said curtain, vertically disposed side wall strips having spaced guides sealingly engaged with portions of said curtain in the lowered position thereof, said curtain, at its lower edge, having heavy ballast means, said ballast means being ilexible in a vertical plane but not in a horizontal plane whereby said lower edge is enabled to conform to vertical irregularities of the iloor but stiffens the lower edge of said curtain against flexure in a horizontal plane.

References Cited in the tile of this patent UNITED STATES PATENTS 305,317 Mallory Sept. 16, 1884 1,147,188 Rojas July 20, 1915 1,730,529 Robbins Oct. 8, 1929 1,756,043 Weidhaas Apr. 29, 1930 1,908,989 Lahey etal May 16, 1933 1,983,583 Timko Dec. ll, 1934 2,509,398 Peremi et al May 30, 1950 2,978,019 Carlo Apr. 4, 1961 OTHER REFERENCES Publication, Architectural Forum, October 1959, vol. 111, No. 4, pp. 63 and 64.

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