US3024068A - Demountable furniture web construction - Google Patents

Description

Marchv 6, 1962 c. EAMES DEMOUNTABLE FURNITURE WEB CONSTRUCTION 2 Sheets-Sheet 1 Filed April 8, 1959 P l l H n l l H width wnufll 1 n i INVENTOR. CHARLES EAMES ATTQRNEYS March 6, 1962 c. EAMES 3,@24,068

DEMOUNTABLE FURNITURE was CONSTRUCTION Filed April 8, 1959 2 Sheets-Sheet 2 s4 66 F76 60 e2 F/G/Z s4 66 62 74 INVENTOR. CHARLES EAMES ATTQWNEW traits tas saunas Patented Mar. 6, 1962 3,024,068 DEMOUNTABLE FURNITURE WEB CUNhTRIKITiON (lharics lEames, Venice, (Ialifi, assignor to Herman Miiier, Inc, a corporation of Michigan Filed Apr. 8, 1959, Ser. No. 304,992 I3 Ciaims. (III. 297-455) This invention relates to furniture. More particularly, it relates to a demountable web for use with a chair frame and the like of the type disclosed in a co-pending application, Serial No. 764,059, filed September 29, 1958, for Web and Spreader Furniture Construction, of which the instant application is a continuation-in-part.

In said co-pending application, there is disclosed a furniture construction involving a chair frame of unique structure. The frame comprises a pair of side rails, each of which in side view is curved in the form of a lazy L. The side rails are held rigidly in spaced relationship by a pair of Spreaders. One of the Spreaders is secured to a base to support the entire frame structure. The side rails each have an outwardly opening channel or groove extending their entire length. Across the rails and from end to end thereof, there is mounted a web which functions to support the body of a user of the chair. The lateral margins of the web are disposed in the outwardly opening channels of the side rails. Moreover, the construction of the frame and web and the manner of installing the Web are such that the web, when mounted, is under tension at all times.

Among the purposes of this invention is to provide a web to be stretched between a pair of frame members of a unit of furniture as, for example, the chair disclosed in said co-pending application.

This web has the advantage of being readily mountable and demountable and these operations may be performed without the use of conventional fasteners. The elimination of such fasteners is advantageous. It distributes the loads evenly along the margins of the web rather than concentrating them in the areas of the fasteners. This reduces the strength requirements of the web as well as structural failure. It also makes it possible to mount and demount the web many times without injury, such as normally occurs with conventional fasteners.

This invention provides a web construction having sufficient structural strength to withstand the severe tension loadings imposed on furniture, such as chairs, and to this end it provides a web of limited stretchability and high tensile strength. The characteristics are combined with light weight and maximum durability even under exterior weather conditions. It also eliminates the necessity for the precise tooling necessary to align the openings for the fasteners in the web and the frame where both are separately formed.

The web will contour smoothly and readily under the users body without points of concentrated resistance. The design of the web also incorporates bands of reinforcement in areas (such as the small of the back) where added support to the body contributes greatly to the comfort of the user. In past constructions, attempts to use light weight webs in chairs have not proven satisfactory because in the normal areas of concentrated loads they have exhibited excessive distortion, forcing the user to assume an uncomfortable posture. This invention eliminates this problem without creating zones of excessive resistance to deflection.

In accordance with the teachings of this invention, the reinforcement bands are arranged in such a manner as to relocate the areas of greater load in places other than where they would normally occur if the web were a simple, continuous web, and therein lies the nub of the comfort provided by the web of this invention. The reinforcement bands are placed above and below the buttocks supporting area to reduce the load there under use conditions and carry more of the body weight on the upper legs and, more important, the small of the back. It is the intermediate band, and its location, more than any other single factor which makes the web or sling of this invention work better than others.

FIG. 1 is a plan view of a preferred embodiment of the demountable, furniture web construction of this invention prior to installation in a furniture frame of the type described.

FIG. 2 is a longitudinal sectional view taken along the plane IIII of FIG. 1.

FIG. 3 is an enlarged sectional view taken along the plane III-III of FIG. 1.

FIG. 4 is a sectional view taken along the plane IV-IV of FIG. 1.

FIG. 5 is a sectional view of a modification of that portion of the web construction illustrated in FIG. 4.

FIG. 6 is a sectional view showing the embodiment of FIG. 4 in installed position.

FIG. 7 is a sectionalized, perspective view of the embodiment of FIG. 4.

FIG. 8 is a sectionalized, perspective view showing the embodiment of FIG. 4 in installed position.

FIG. 9 is a sectional view showing another modification of that portion of the web construction illustrated in FIG. 4.

FIG. 10 is a plan view of another preferred embodiment of the demountable web construction of this invention at a semifinal step of its assembly.

FIG. 11 is a longitudinal side view of the demountable web construction of FIG. 10 as it might appear after the first step in its manufacture.

FIG. 12 is a sectional view taken along the plane XII- XII of FIG. 10.

FIG. 13 is a sectional view taken as along the plane XII-XII after another step in the manufacture of this embodiment has been performed.

FIG. 14 is a sectional view taken as along the plane XII-XII after a finishing step in the manufacture of this embodiment has been performed.

FIG. 15 is a sectional view taken as along the plane XIIXII after this embodiment has been installed in a chair frame of the type described in said co-pending application.

FIG. 16 is a perspective view of the bottom end of the embodiment of FIG. 10 in installed position. 1

FIG. 17 is a cross sectional view looking towards the front of the chair frame in the view of FIG. 16.

In general, the drawings broadly disclose a web basically comprising a generally rectangular sheet of material having the properties of flexibility, high tensile strength and stretchability. At least at the upper end or upper body supporting portion, at an intermediate or small-of the-back supporting portion and at the lower end or lower body supporting portion of the sheet there is provided a transversely disposed band of reinforcement. This band in each case may be formed from a preferably underlying, reinforcement panel of sheet material having substantially the same properties of flexibility, tensile strength and stretchability. Adjacent each side margin of the sheet there is provided a stiffener element. Preferably each stiffener element is in the form of a cross sectionally rigid but longitudinally flexible strip underlying the sheet and extending from the region of the upper end portion of the sheet to the region of the lower end portion of the sheet. The length of the strip is such that the entire stiffener element can be accommodated in the outwardly opening channel of furniture frame such as a chair frame side rail. Preferably, each side portion of the sheet is wrapped under the corresponding reinforcement strip and the bottom section of the side portion secured to the top section of the side portion. In addition, the upper and lower ends of the sheet may be folded under and the top and bottom sections thus formed secured together.

Specifically, FIGS. l-9 illustrate a demountable web 10 in the form of a composite structure. This embodiment of the web may be broadly described as a pad having a pattern surface. In particular, the web 10 comprises a generally rectangular sheet 18 having a lower end L and an upper end H. Under use conditions, the lower end region of the sheet 18 functions to support an average sitters body at the lower thighs while the upper end region of the sheet 18 functions to support the upper portion of the average sitters body. This upper portion may be just the shoulders as in the case of the low back type of chair frame. This upper portion may also include the head as in the case of the high back type of chair frame.

Underlying the sheet 18 is a reinforcement and cush ioning structure. This structure comprises a bottom sheet 12 having generally the same plan view shape as the overlying main sheet 18 and thus a lower end L and an upper end H. Preferably, however, the bottom sheet 12 is somewhat shorter in longitudinal and lateral dimensions whereby, when in unfolded condition, the peripheral portion of the overlying sheet 18 overlaps the peripheral portion of the bottom sheet 12.

superposed on the bottom sheet 12 are three, generally rectangular, reinforcement panels 14a, 14b and 140. One panel 14a is transversely arranged under the lower end region or leg supporting portion of the overlying main sheet 18. The second panel 14b is transversely arranged under an intermediate region of the overlying main sheet 18, which corresponds substantially to the small-of-the-back supporting region of the web 11 The third panel 14c is transversely arranged under the upper end or H end region of the overlying main sheet 18, which region functions as an upper body support.

Covering generally the bottom sheet 12 and the reinforcement panels 14a, 14b, and 14c, but disposed beneath the overlying main sheet 18 is a layer of foam cushioning material 16. The lateral dimension of the foam cushioning material 16 is preferably less than the lateral dimension of the bottom sheet 12 and the reinforcement panels. The longitudinal dimension of the foam cushioning mate'- rial is also less than the longitudinal dimension of the bottom sheet 12. The layer of foam cushioning material 16 is longitudinally interrupted by a plurality of transversely and inwardly directed depressions 20 of the overlying main sheet 18 and corresponding transversely and inwardly directed depressions 22 of the bottom sheet 12 and reinforcement panels combination. Consequently, the foam cushioning material 16 is disposed in transversely arranged pockets and the top and bottom sides of the web 10 have a tufted or pattern appearance.

The web 10 is provided with a stiffener or reinforcement strip element 24 along each lateral margin. As shown in FIG. 4, each stiffener element is disposed underneath the underlying main sheet 18 in a pocket 23 formed preferably by folding under the corresponding overlapping side portions 31 of the overlying sheet 18.

The web 10 is also preferably provided with a transversely disposed stiffener element 26 adjacent the H end thereof and a transversely disposed stiffener element 28 adjacent the L end thereof. As indicated in FIG. 3, each stiffener element 26 and 28 is likewise disposed underneath the overlying main sheet 18 in a pocket 25. This pocket is formed preferably by wrapping the individual elements 26 and 28 in the corresponding overlapping end portions 29 of the overlying main sheet 18.

The lateral stiffener elements 24 are indicated in FIG. 1 as terminating short of the ends of the web 10. Likewise, the transverse stifiener elements 26 and 28 are indicated in FIG. 1 as terminating short of the sides of the web 10. Thus, each corner region of the web 10 is adapted thereby for being secured to the ends of the chair frame side rails 32 in the manner indicated in FIGS, 16 and 17 and to be described hereinafter. Moreover, there is no need for the lateral overlapping portions of the main sheet 18 to extend from end to end of said sheet. Indeed, it is preferred that the lateral overlapping portions of the main sheet be only substantially co-extensive with the corresponding stiffener elements 24. Consequently, the main sheet 18 is preferably formed with the corners cut away. In either case, however, the overlapping portions 29 and 31 appear and function as flap members.

Preferably, each of the stiffener elements 24, 26 and 28 are further secured to the main sheet 18 by a sewn thread 30.

The web 10 may be assembled by the following suggested procedure. First, the bottom sheet 12 is laid out on a horizontal surface, such as, for example, a tray for a heat sealing machine. Next, the reinforcement bands or panels 14a, 14b and are placed in position over the bottom sheet 12. In such position, the marginal ends of the reinforcement panels and bottom sheet should be in substantial alignment. A slab of foam cushioning material 16 is then placed in position over the bottom sheet 12 and reinforcement panels 14a, 14b and 14c. Next, the main sheet 18 is placed in position over the slab of foam cushioning material 16. If the various sheets have already been trimmed, the fiap members 29 and 31 of the main sheet 18, however, will extend outwardly from the sheet 18 beyond the marginal sides and ends of the slab of cushioning material 16, the reinforcement panels 14a, 14b and 140, and the bottom sheet 12.

The assembled structure is then placed into a conventional type, heat sealing machine comprising a press and a top side die. The main sheet 18 should be facing this die. The die comprises transverse electrodes corresponding to the transverse depressions 20 of the web 10, Preferably, the die also comprises a perimeter electrode corresponding to the inner portion of the generally rectangular periphery of the web 10 between the pockets 23 and 25 (yet to be formed) and the foam cushioning material 16. The machine is operated and the internally heat sealed depressions 20 and 22 are formed. In addition, the bottom sheet 12, the reinforcement panels 14a, 14b and 140, and main sheet 18 are peripherally bonded together.

At this point, if trimming has not already occurred, the bottom sheet 12 and reinforcement panels 14a, 14b and 140 should be trimmed back to the marginal peripheral heat seal and, if not already done, the corner portions of the main sheet 18 cut away, leaving the flap members 29 and 31 intact.

The stiffener elements 24, 26 and 28 are then placed in position and secured to the main sheet 18, preferably in the following described manner.

The heat sealed structure is turned bottom side up and the lateral stiffener elements 24 are placed on the bottom sheet 12 with the outside lateral edge of each in substantial alignment with the corresponding lateral edge of the bottom sheet 12. A thread 30 is then sewn through each stiffener element and underlying bottom sheet 12, reinforcement panels 14a, b and c and main sheet 12. Preferably, the sewing line on each side of the main sheet 18 extends from one end to the other end of the web on each side thereof. The lateral flap 31 on each side of the main sheet 18 is then folded over the corresponding stiffener elements 24 and a thread 30 sewn through each entire marginal combination. See FIG. 4 for a cross sectional view of this combination with the web 10 turned over. Again it is preferred that the sewing line on each side extend from one end to the other end of the main sheet 18.

The end stiffener elements 26 and 28 are placed on the spanned end flaps 29 with the outside edge of each aligned with the edge of the corresponding end flaps 29'. One end flap 29 and stiffener element combination is then rolled over inwardly once whereby the flap is wrapped around the stiffener element. A thread 36 is then stitched through the stiffener element, the flap on both the top and bottom sides of the stiffener element and throughout the length of the stiffener element. The flap and stiffener element combination are then rolled over inwardly once more. The relative widths of the end flaps 29 and stiffener elements 26 and 28 are such that this last step, remembering that at this point the web It} is bottom side up, places the wrapped end stiffener elements in each case on top of the marginal portions of the bottom sheet 12 and respective reinforcement panels 14a and Me. A thread 30 is then sewn through the combination of the folded end flap, stiffener element, reinforcement panel and bottom sheet for the full length of the stiffener element and preferably from one end of the end flap member 29 to the other end. The same procedure is repeated with the other end flap and stiffener element combination. See FIG. 3 for a cross sectional view of the combination with the web It turned over. The web is now in assembled condition and ready for installation into a furniture frame of the type described.

Other modes of assembly can be used. Thus, as in the case of the embodiment of FIG. 5, the lateral stiffener elements 24 can be mounted in a similar fashion to the end stiffener elements. Thus, each stiffener elements 24 can be placed in the corresponding lateral flap 31 and each combination of the stiffener element 24 and lateral flap 31 rolled over twice. A thread can be sewn through the once rolled over combination and then again through the twice rolled over combination. However, it can also be done as indicated in FIG. 5. In this embodiment, the thread 30 is only sewn through the combination once and then it is done after it is rolled over twice. This is an advantage since it only involves one sewing operation per side. However, this mode of procedure may not be too satisfactory if the main sheet 1'8 has a slippery bottom surface for the stiffener element 24 and it becomes diflicult to maintain the combination in a tightly folded condition before sewing.

Still another mode of assembly is represented by the modification of FIG. 9. In this embodiment, the stiffener elements 26, 26 and 28 may be incorporated into the web construction prior to the heat sealing step or, if after the heat sealing step, the perimeter electrode of the top side die should be rather narrow instead of wide as in the case of the embodiments of FIGS. 3, 4 and 5. Preferably, however, the stiffener elements are installed in the instant embodiment prior to heat sealing. In such case the web 10 is preferably assembled bottom side up. In such condition the stiffener element 24, for example, is placed over the main sheet 18 and underneath the reinforcement panels (such as 14b) and bottom sheet 12 with the lateral outside edge thereof substantially aligned with the lateral edges of the reinforcement panels. The lateral flap 31 is then folded over the combination and secured by sewing a thread 30 along a line adjacent the inside lateral edge of the stiffener element and through the flap 31, bottom sheet 12, reinforcement panels and main sheet 18. The heat sealing step is then performed. In this regard the perimeter electrode of the top side die should comprise at least a narrow, inner portion to heat seal the web 10 between the stiffener element and the foam cushioning material 16. Moreover, especially when the stiffener element comprises a thermoplastic material to which the sheets and panels can be bonded, the electrode should comprise a wide, outer portion to heat seal the entire margin of the web 10.

This embodiment has an advantage in that a tightly folded condition can be obtained even if the main sheet 18 has a slippery surface for the stiffener element. Moreover, this embodiment is useful when the stiffener ele- 6 ment is a material, such as aluminum and the like, which is difficult to penetrate with a sewing needle. However, the marginal fastening is not as permanent and not as strong as in the embodiments of FIGS. 4 and 5.

To install the web in in a chair frame of the type previously described herein, one of the side rails 3-2 of the frame is disengaged from the spreaders and moved inwardly towards the other side rail. The web it), main sheet 18 facing upwardly, is then draped over the side rails with the L end of the web 10 at the L end of the rails and the H end of the Web It) at the H end of the rails. Each of the lateral margins is folded downwardly and inwardly and then inserted into the corresponding outwardly facing channel 3% of the rail 32. See FIGS. 6 and 8. The body of the stiffener element 24 in combination with the bottom and main sheets and reinforcement panels is preferably in press fit with the channel 34. At each end of the Web If), the ends of the web are coiled into front and back terminal rolls, the ends of the rolls being formed around the ends of the rails. This is made possible because of the absence of the stiffener elements at the end regions. At each end of the rails, the lateral corner portion of the web If) overlapping the rail is folded over and stuffed into the socket 36 provided at the end of the rails 32. A cone shaped, washer type, fitting 37 is then inserted into the socket 36 over the web material therein, and a flat head machine screw inserted through the fitting 37 and screwed into the threaded opening 33 at the back end of the socket Ed until tight. With the web It) thus mounted on each rail 32 (see FIGS. 16 and 17), the one rail disengaged from the spreaders is pulled laterally until it can be again engaged with the spreaders, and is then so engaged. The limited stretchahility of the web it permits this to be done without injury to the components of the web Iii. The web Iii, under tension, is now ready for use.

To remove the web 10, one of the side rails is merely pulled laterally until it is disengaged from the spreaders and the assembly procedure is reversed.

Materials of construction used in forming the web 10 of FIGS. 1-9 are conventional, and, therefore, need not be described in detail. In general, the materials used in the web must be flexible and preferably have a limited amount of resilience. The materials generally must have limited stretchability and have relatively high tensile strength to withstand the forces imposed upon them under use conditions.

Specifically, the bottom sheet 12 and the main sheet 18 may be of a sheet-like material such as leather or a synthetic, polymeric material such as a cured, virgin polyvinyl chloride polymer with or without internal reinforcement. Preferably, the material should be thermoplastic and capable of being heat sealed. A material found to be satisfactory for both the main sheet 18 and bottom sheet 12 is the vinyl covered, upholstery fabric sold under the trade designation Naugahyde.

The reinforcement panels 14a, 14b and Me may be any suitable reinforcement sheeting and fabric. Particularly satisfactory has been a vinyl-coated, nylon Woven fabric, such as that marketed under the trade designation Fiberthin.

The foam cushioning material may be foam rubber, vinyl foam, the more recently introduced flexible polyurethane foam and the like. Particularly satisfactory has been vinyl foam since it is thermoplastic and, therefore, can be heat sealed at the margins thereof.

The stiffener elements 24, 26 and 2? are preferably of a bendable or semi-flexible material which, however, is highly resistant to crushing. Each stiffener element is generally rectangular in cross section with its greater dimension extending laterally of the chair as the web is installed. It is of a material of such resistance to crushing that it will not buckle across its greater cross sectional dimension. As an example of a suitable mate- 7 rial for the stiffener elements, a pressed fiber board formed under heat and pressure may be used. Also, a tempered pressed board of cellulosic or ligneous origin may be used. Also usable are metallic and plastic elements, such as, for example, aluminum and styrene. Vulcanized fiber strips have been used. However, problems arise when the vulcanized fibers are wetted, such as might occur when the web it is in outdoor use. Particularly satisfactory have been strips of a vinyl and rubber compound marketed under the designation in the trade of Royalite, which are particularly waterproof and can be used in heat sealing (see P16. 9).

The embodiment of FIGS. ll5 comprises a Web St: having a lower or leg end L and an upper or head end H. The web comprises a single sheet of fabric 52. The sheet of fabric is folded in a special manner to provide a band of reinforcement in the region 53a of the L end of the web, a band of reinforcement in the intermediate, small-of-the-back supporting region 53b of the web, and a band of reinforcement in the region 530 of the H end of the web (upper shoulders supporting region).

At the H end region 530 of the web 56, there is provided a top panel 54, a middle panel 56 and a bottom panel 58. These panels are formed by first folding the fabric 52 back upon itself (180) and then again folding the combination back upon itself.

At the small-of-the-back supporting region 53b of the web 50, the bottom panel 53 of the H end region becomes the top panel. Beneath the top panel 58 in this middle region 531) is a middle panel 60 and a bottom panel 62. These panels are formed by folding the fabric 52 back once underneath the top panel 58 towards the H end of the web 50.

At the L end region 5312 of the web 59, the bottom panel 62 of the small-of-the-back supporting region 53]) becomes the top panel. Beneath the top panel 62 of the L end region is a middle panel 66 and a bottom panel 64. These panels are formed by folding the fabric 52 back underneath itself twice whereby the end portion of the fabric forms the middle panel 66.

The H end margin and the L end margin of the web SE} are formed by merely sewing a thread 74 through the panels along a line extending from one side to the other side of the web. Note, however, that otherwise the fabric panels of the web are not transversely fastened together.

Along each lateral margin of the web 50, there is provided a lateral stiffener element 68. As shown in FIGS. 14 and 15, each stiffener element 63 is disposed on the underside of the folded fabric 52. in a pocket 67 formed by a folded under, corresponding side portion of the folded fabric 52, as shown in FIG. l4. Each stiffener element 68, it will be observed, terminates short of the ends of the fabric.

To form the "lateral margins of the web 50, the lateral stiffener elements 68 are positioned longitudinally on the bottom side of the folded fabric 52 (folded as indicated in FIG. 11) with the lateral outside edge of each element spaced from the lateral edge of the various layers of fabric whereby the layers of fabric overlap the stiffener elements 68 laterally. A thread 74 is then sewn through each stiffener element 68 and overlying layers of fabric along the entire length of the stiffener element. At this stage, the web 50 appears as shown in FIGS. 10 and 12. The next step is to trim the overlapping sides of the underlying panels in the three regions 53a, 53b and 530 back to the outside lateral edge of the stiffener element 68, leaving the top panel overlapping portion in each region as is, as shown in FIG. 13. The overlapping lateral portion of each top panel in the three regions and of the panels of fabric between the regions is then folded under the stiffener element 68 as shown in FEG. 14. If desired, the folded under portion of the fabric 52 may be sewn to the lateral stiffener element 63 on each side. This, however, is not necessary.

The web 50 is installed in the same fashion as indicated in the description of the embodiment of FIGS. 1-9. Thus, with the top side of the web 5ft facing upwardly, each lateral margin of the web is folded down and inwardly, and inserted into the outwardly facing side channel 34 of the corresponding side rail 32, as shown in H6. 13. At each end of the web 56, the web is coiled into a terminal transverse roll (FIG. 16). At each corner of the web 50, the lateral portions of the web overlapping the side rail are folded under and inserted into the socket 36 at the corresponding end of the side rail 32. A coneheaded countersunk screw 4% and machined washer 3-7 are then screwed into its screw hole 38 at the end of the socket 36 and tightened down over the fabric to form a positive friction lock of the web, as shown in FIG. 17.

The materials of construction used in the embodiment of FIGS. 10l7 are conventional and need not be described in great detail. The fabric 52 should be of a material that is flexible, has high tensile strength, and is slightly stretchable. The fabric 52 may comprise fibers of natural and of synthetic origin. A polyvinylidene chloride polymer-coated, spun, fabric material obtainable under the trade designation Saran has been found to he satisfactory. The stiffener elements may be as previously described.

These materials of construction for both embodiments described herein are recited merely as illustrative of the structure of the web and are not to be considered limitations upon the invention since the particular composition of materials used in the web are not, of themselves, a part of this invention, except that they have the characteristics previously recited as necessary or desirable for obtaining the objectives of the invention.

The web construction as contained in the two embodiments described is relatively easy to assemble. Extreme accuracy in shaping and dimensioning the web is not necessary. The web construction is such that it can be readily installed in, and demcunted from, the chair frame described.

Once installed, the web construction of this invention provides a comfortable and safe seat. As already mentioned herein, the side margins of the web construction it and 59 are seated over the top face of the rails 32 and are wrapped about the outer top edge of the rails as illustrated in FIGS. 6-8 and FIG. 13. The edge margins of the web having the stiffener element are seated in the outer channel 34 of the rails. As so mounted, that portion of the web having the stiffener is wrapped about the edge of the rail and therefore is directed in the opposite direction to the main body portion of the web. As so mounted, tension applied to the web, such as occurs when a person is seated in the chair, cannot dislodge the edges of the web from the outer channels even though no fasteners are used to secure these edges to the rails. The forces created about the edge of the web when the body portion thereof is placed in tension cannot pull the stiffener from the channel since this would require the forces to reverse their direction. The tendency is to rock the stiffener out of the channel with the inner end attempting to swing downwardly. Since the stiffener is of a material which resists crushing and will not bend in cross section, this rocking is prevented because the stiffener then forms a wedge between the upper and lower surfaces of the channel. The greater the tension applied to the web, the greater the wedging action created by the stiffener and thus the lateral edges of the web are gripped by the rail.

This provides a positive means of securing the web to the rails without the use of fasteners.

Furthermore, it permits it to be done with the forces generated in the web being transferred to the frame throughout all portions of the length of the web, rather than at points of concentrated load transfer, such as occurs with the use of conventional fasteners. As already mentioned herein, the stiffener elements in each embodiment terminate just short of the ends of the web, permitting the ends of the web to be coiled into the front and back terminal rolls (FIGS. 16 and 17). These rolls form a generally tubular structure at both ends of the web. The rolls or tubes formed in the ends of the web reinforce the ends of the web and prevent the ends of the web from forming a line of higher resistance to contouring when the chair is occupied, as so often occurs in furniture of this type.

Another major advantage of'the web construction of this invention is that its structure will comfortably accommodate all types of sitting posture.

Due to the reinforcement structure and arrangement thereof, the web under use conditions is capable of comfortably receiving and supporting the upright type of sitter, the reclining type of sitter and the edge type of sitter. Indeed, the web of this invention, when applied to chairs of the type described promotes and encourages good sitting posture without discomfort to the sitter.

In both embodiments, it accomplishes this because of the placement of the reinforcement bands above and below the buttocks supporting area and particularly in the small-of-the-back supporting area. Under use conditions, each band of reinforcement and particularly the band of reinforcement in the small-of-the-back supporting area reduces the load on the buttocks supporting area and the shoulder supporting area, and causes the body weight of the sitter to be carried by his upper legs and the small of his back.

In the folded fabric embodiment (FIGS. -15), it further accomplishes this by the longitudinal freedom of movement of the fabric 52 in the small-of-the-back supporting region. The center fold on panel 60 in this region, not being transversely sewn or fastened to the overlying and underlying panels 53 and 62, enables the web 54} in the small-of-the-back supporting region 53b to stretch longitudinally of the web under use conditions. This provides more fullness in the buttocks supporting area and shoulder supporting area, thus further increasing the load supported by the small of the back and upper legs of the sitter and further reducing the load on the buttocks and shoulder of the sitter.

Still another major advantage of the web construction of this invention is that its structure is inherently safe. Due to the reinforcement structure, the web under use conditions is capable of withstanding enormous shock loads, such as would be encountered when a sitter of heavy weight of any of the sitting posture types suddenly drops into a chair.

While two preferred embodiments of this invention have been described, it will be recognized that various modifications may be made. Such of these modifications as incorporate the principles of this invention are to be considered as included in the hereinafter appended claims,

unless these claims by their language expressly state otherwise.

I claim:

1. A flexible web member for an article of furniture characterized by a pair of side rail means across which said web when mounted is stretched, said side rail means each having outwardly facing, lateral channels extending substantially the entire length thereof, which comprises: flexible sheet means folded transversely 180 at the ends of said sheet means and intermediate thereof into underlying, transverse, reinforcement panel means; stiffener element means characterized by cross-sectional rigidity and longitudinal flexibility disposed longitudinally of said sheet means and along the lateral margins of said sheet means; and means for fastening together said sheet means and said stiffener element means, whereby said lateral margins are adapted to be received in said lateral channels in wedge fit.

2. A flexible web member for an article of furniture characterized by a pair of side rail means across which said web when mounted is stretched, said side rail means each having outwardly facing, lateral channels extending substantially the entire length thereof, which comprises: flexible sheet means folded transversely at the ends of said sheet means and intermediate thereof into underlying transverse reinforcement panel means; stiffener element means characterized by cross-sectional rigidity and longitudinal flexibility disposed longitudinally of said sheet means and under the lateral margins thereof, the lateral portions of said sheet means comprising lateral flap means capable of being folded 180 under said lateral stiffener element means, whereby said lateral margins with said lateral flap means so folded are adapted to be received in said lateral channels in wedge fit.

3. A flexible web member for an article of furniture characterized by a pair of side rail means between which said web when mounted is stretched, said side rail means each having outwardly facing, lateral channels extending substantially the entire length thereof, said web being the sole means of support for the body of a person on said article of furniture, which comprises: a main flexible sheet means having an upper body supporting region, a small-of-the-back supporting region, and a lower body supporting region; flexible reinforcement panel means underlying each of said regions incorporated into said web member and secured to said flexible sheet means adjacent the lateral margins of said web member; stiffener element means extending longitudinally of said main sheet means and underlying said main sheet means and said panel means at the lateral margins thereof; and means for fastening together said sheet means, said panel means and said stiffener element means, said main sheet means comprising lateral flap extensions foldable under said stiffener element means, whereby the lateral margins of said web are adapted to be received in said lateral channels in wedge fit.

4. A flexible web member for an article of furniture characterized by a pair of side rail means between which said web when mounted is stretched, said side rail means each having outwardly facing, lateral channels extending substantially the entire length thereof, said web being the sole means of support for the body of a person on said article of furniture, which comprises: a main flexible sheet means having an upper body supporting region, a smallof-the-back supporting region, and a lower body supporting region; flexible reinforcement panel means underlying each of said regions of said main sheet means, said panel means being formed by 180 folds of said flexible sheet means; stiffener element means characterized by crosssectional rigidity and longitudinal flexibility extending longitudinally of said main sheet means and underlying said main sheet means and said panel means at the lateral margins thereof; and means for fastening together said sheet means, said panel means and said stiffener element means, said main sheet means comprising lateral flap extensions foldable under said stiffener element means, whereby the lateral margins of said web are adapted to be received in said lateral channels in wedge fit.

5. A flexible web member for an article of furniture characterized by a pair of side rail means across which said web when mounted is stretched, said side rail means each having outwardly facing, lateral channels extending substantially the entire length thereof, and having socket means at each end thereof with fastener means, said web being the sole means of support for the body of a person on said article of furniture, which comprises: a main flexible sheet means having an upper body supporting region, a small-of-the-back supporting region, and a lower body supporting region; flexible reinforcement panel means underlying each of said regions, said panel means being formed by 180 folds of said flexible sheet means, said folds in said small-of-the-back supporting region having a longitudinal freedom of movement; stiffener element means characterized by cross-sectional rigidity and longitudinal flexibility extending longitudinally of said main sheet means and underlying said sheet means and said panel means at the lateral margins thereof, said stiffener element means terminating short of the ends of said sheet means, whereby the ends of said sheet may be coiled in terminal rolls, the ends of said rolls being capable of being folded under and inserted into said socket means absent said fastener means; and means for fastening together said sheet means, said panel means and said stiffener element means, said main sheet means comprising lateral flap extensions foldable under said stiffener element means, whereby the lateral margins of said web are adapted to be received in said lateral channels in wedge fit.

6. A flexible web member for an article of furniture characterized by a pair of side rail means across which said web when mounted is stretched, said side rail means each having outwardly facing, lateral channels extending substantially the entire length thereof, said web being the sole means of support for the body of a person on said article of furniture, which comprises: a main flexible sheet means having an upper body supporting region, a small-of-the-back supporting region, and a lower body supporting region; foam cushioning means subjacent said flexible sheet means; fiexible reinforcement panel means underlying said foam cushioning means in each of said regions; a flexible, bottom sheet means underlying said panel means and said foam cushioning means; the lateral portions of said main sheet means, reinforcement panel means and bottom sheet means extending beyond the lateral margin of said foam cushioning means; stiffener element means extending longitudinally of said web and underlying said main sheet means, said panel means and said bottom sheet means at the lateral extensions thereof; and means for fastening together said main sheet means, said panel means, said stiffener element means and said bottom sheet means, said main sheet means comprising lateral flap extensions foldable under said stiffener element means, said lateral flap extension being folded under said stiffener element means and fastened thereto, whereby the lateral margins of said web are adapted to be received in said lateral channels in wedge fit.

7. A flexible web member for an article of furniture characterized by a pair of side rail means across which said web when mounted is stretched, said side rail means each having outwardly facing, lateral channels extending substantially the entire length thereof and having socket means at each end thereof with fastener means, said web being the sole means of support for the body of a person on said article of furniture, which comprises: a main flexible sheet means having an upper body supporting region, a small-of-the-back supporting region, and a lower body supporting region; foam cushioning means subjacent said flexible sheet means; flexible reinforcement panel means underlying said foam cushioning means in each of said regions; a flexible bottom sheet means underlying said panel means and said foam cushioning means, the lateral portions of said main sheet means, said panel means and said bottom sheet means extending beyond the lateral margin of said foam cushioning means; stiffener element means extending longitudinally of said web, underlying said lateral extensions of said main sheet means, said panel means and said bottom sheet means, and terminating short of the ends of said main sheet means, whereby the ends of said main sheet may be coiled in terminal rolls, the ends of said rolls being capable of being folded under and inserted into said socket means absent said fastener means; and means for fastening together said main sheet means, said panel means, said bottom sheet means and said stiffener element means,

said main sheet means comprising lateral flap extensions folded under said stiffener element means and fastened thereto, whereby the lateral margins of said web are adapted to be received in said lateral channels in wedge fit.

8. A flexible web according to claim 7, which comprises: stiffener element means adjacent each end of said web, the ends of said main sheet means, said panel means and said bottom sheet means extending beyond the end margin of said foam cushioning material, said stiffener element terminating short of the sides of said web and being seated in a pocket formed by a folded under flap portion of said main sheet means; and means for fastening together said main sheet means, said reinforcement panel means, said bottom sheet means, and said end stiffener element means.

9. A flexible web according to claim 7, wherein said main sheet means and said bottom sheet means are of a thermoplastic material and transversely of said web, said main sheet member comprises depressed portions in heat sealed contact with the underlying reinforcement panel means and bottom sheet means.

10. A flexible web according to claim 7, wherein the lateral portions of said main sheet means, said reinforcement panel means and said bottom sheet means between said foam cushioning material means and said stiffener element means are in heat sealed contact.

11. A flexible web member for an article of furniture comprising: a flexible surface panel, a plurality of underlying reinforcement members; said members being disposed at each end of said web member and intermediate thereof; an elongated stiffener at each end of a pair of opposite margins of said web member; said surface panel and said reinforcement members being joined adjacent said stiffener; said stiffeners being characterized by crosssectional rigidity and longitudinal flexibility.

12. A flexible Web member for an article of furniture comprising: a flexible surface panel, a flexible back panel; a plurality of underlying reinforcement members, said members being disposed at each end of said web member and intermediate thereof; said panels and reinforcement members being characterized by high tensile strength and limited stretchability; an interlayer between said surface and back panels of flexible foamaceous material; an elongated stiffener at each of a pair of opposite margins of said web member; said surface panel, back panel and said reinforcement members being joined adjacent said stiffener; said stiffeners being characterized by cross-sectioned rigidity and longitudinal flexibility.

13. A flexible web member for an article of furniture comprising: a flexible surface panel of high tensile strength and limited stretchability; said panel having reinforcement zones at each of its ends and intermediate thereof characterized by plural layers of said panel folded back upon itself; an elongated stiffener secured to a pair of opposite margins of said web members, said margins being at the opposite ends of said reinforcement zones; said stiffeners being characterized by cross-sectioned rigidity and longitudinal flexibility.

References Cited in the file of this patent UNITED STATES PATENTS 1,014,848 Reinert Jan. 16, 1912 1,246,544 Chassaing Nov. 13, 1917 1,281,385 Johnson Oct. 15, 1918 1,882,176 Brown Oct. 11, 1932 2,457,978 Curran Jan. 4, 1949 2,761,153 Mew Sept. 4, 1956

Images