Textile web corrugating machine and method

Abstract: A textile web corrugating machine comprises a support table (11) along which a textile web (10) is transported, a folding plate (21) disposed above the support table for folding in a generally zig-zag fashion (10c) the textile web (10) as it passes below the folding plate, a retainer member (31) positioned above the support table (11) in face-to-face relationship with the folding plate (21) for urging folds (10c) successively formed on the textile web into a web transport passage positioned downstream of the support table (11) with respect to the direction of transport of the textile web, and a compressing unit (42) disposed along the web transport passage for applying a compressive force to the successively formed folds (10c) from above and also from a lateral direction.

Description: In general, a web of textile material is often required to have a substantial thickness depending on the application thereof and, for this purpose, the web of textile material is gathered or corrugated over the length thereof so that the resultant corrugated web of textile material can have a required thickness. As far as the textile web having a substantial thickness is concerned, one of the textile webs currently available in the market is of a type wherein, as shown in Fig. 7 of the accompanying drawings, textile fibers generally identified by 1 are oriented in two dimensions in transverse directions generally parallel to and perpendicular to the lengthwise direction of the textile web. Another one of the conventional textile webs is of a type wherein, as shown in Fig. 8 of the same, the textile fibers are oriented in two dimensions not only in the transverse directions parallel to and perpendicular to the lengthwise direction thereof, but also in a direction generally parallel to the thickness thereof as indicated by D. Both of the conventional textile webs shown respectively in Figs. 7 and 8 contain binder particles 2 dispersed therein to bind the textile fibers 1 together. Another conventional textile web is a needle-punched carpet as shown in Fig. 9. The needle-punched carpet is formed by needle-punching a layer of textile fibers to avoid separation of the fibers and also to collect the fibers in a desired density while exhibiting a desired physical strength in directions both parallel and transverse to the lengthwise direction. Both of the conventional textile webs shown in Figs. 7 and 8 are prepared firstly by collecting textile fibers on a conveyor onto which the textile fibers are discharged at high speed, or by laminating the discharged textile fibers. However, in order for the textile web to have a relatively great thickness, the machine for the manufacture thereof is required to be expensive and bulky. Also, for the conventional textile web wherein the textile fibers are oriented in two or three dimensions, the manufacture of a web having large thickness, for example, 20 mm or greater, requires a needle-punching operation, followed by laminating plural textile webs together by the use of a needle-punching technique. In addition, in order for the textile web shown in any one of Figs. 7 and 8 to have a relatively high fiber density, it is necessary to compress and heat-treat bulky fiber webs. A bulky machine is needed. With respect to the conventional textile web shown in Fig. 9, since the punching operation is effected in a direction D generally parallel to the thickness of the textile web, difficulty is encountered in driving a long felt needle through that thickness. Therefore a plurality of needle felts are sewed together by the felt needle, posing a problem in that the thickness of the resultant textile web is limited. In other words, this technique is ineffective to provide a textile web having a required fiber density and also having a required thickness. US-A-1888232 (on which the two-part form of the present claims is based) describes a machine and method for pleating a length of cloth. The cloth is gripped on both faces by the opposed edges of two transversely-extending grippers, drivable in a cyclical motion by a cam drive to form transverse folds in the cloth. Guide members guide each fold into the nip of two rollers which press the folds into permanence. US-A-3323696 also describes a pleating method and apparatus in which opposed edges of two cyclically-moved cloth gripper elements create transverse folds but in a multi-layered web. An adhesive belt passing above the fold-forming elements engages the top projection of each nascent fold and passes with it between two pressing rollers, to form the fold with a top counter-pleat. We address the task of providing new apparatus and methods of processing textile webs by corrugating them. In particular, we would prefer to be able to eliminate at least substantially the problems discussed above in the existing manufacture methods for textile webs. We would prefer to be able to provide a textile web corrugating machine effective to provide a high quality textile web, without the need for bulky and complicated equipment, and with the ability to achieve desired overall thickness and elasticity in the corrugated web. In a first aspect, the present invention provides a textile web corrugating machine having a transport path, along which a textile web to be corrugated is transported in a downstream direction; an elongate folding element extending transversely over the transport path, and a first drive to move the elongate folding element in a repeated cycle of movement relative to the transport path, thereby to engage the textile web and form successive transverse folds therein to corrugate the web; and an elongate retainer element extending transversely over the transport path adjacent and downstream of the folding element, to guide the transverse folds of textile web into a downstream passage portion of the transport path which has means for pressing the corrugated web; characterised in that (a) a support table is provided to support the textile web along at least an upstream portion of the transport path, the folding element and the retaining element being disposed over the support table; (b) the first drive is adapted to drive the folding element in a cycle of movement involving successively movement towards the support table to engage the textile web thereon, movement downstream along the support table to form a transverse fold of the thus-engaged textile web, and movement away from the support table and upstream to disengage from the textile web and return to complete the cycle, and in that (c) a second drive is provided to drive the retainer element, in synchronised relation with the folding element, in a cycle of movement involving successively movement towards the support table to engage the textile web upstream of the transverse fold formed by the folding element, movement downstream along the transport path to urge the transverse fold towards the downstream passage portion of the transport path, and movement away from the support table and upstream to disengage from the transverse fold and return to complete the cycle. In a second aspect the present invention provides a method of corrugating a textile web, comprising transporting the textile web along a transport path in a downstream direction; corrugating the textile web by driving an elongate folding element, extending transversely over the transport path, in a repeated cycle of movement relative to the transport path to engage the textile web and form successive transverse folds therein; guiding the transverse folds of textile web into a downstream passage portion of the transport path, using an elongate retainer element extending transversely over the transport path adjacent and downstream of the folding element to engage the transverse folds, and pressing on the corrugated web in the downstream passage portion; characterised (a) in that along at least an upstream portion of the transport path, the textile web is supported on a support table over which the folding element and the retainer element are disposed; (b) in that the cycle of movement in which the folding element is driven involves successively movement towards the support table to engage the textile web, movement downstream along the support table to form a transverse fold in the textile web, and movement away from the support table and upstream to disengage from the textile web and return to complete the cycle, and (c) in that the retainer element is driven, in synchronised relation with the folding element, in a cycle of movement involving successively movement towards the support table to engage the textile web upstream of the transverse fold formed by the folding element, movement downstream along the transport path to urge the transverse fold towards the downstream passage portion of the transport path, and movement away from the support table and upstream to disengage from the transverse fold and return to complete the cycle. Thus, it will be seen that the textile web corrugating techniques of the present invention use a support table along which the textile web is transported, folding means as specified above disposed over the support table and operable to fold in a generally zig-zag fashion the textile web then passing through a space delimited by the folding means and the support table, a retainer means positioned above the support table in face-to-face relationship with the folding means and operable to urge folds successively formed on the textile web into a web transport passage positioned downstream, preferably downstream of the support table, with respect to the direction of transport, and a compressing means disposed along the web transport passage for applying a compressive force to the successive folds, preferably from above and also from a lateral direction. When the folding means is operable to corrugate the textile web in a generally zig-zag fashion in a direction conforming to the lengthwise direction of the textile web while the retainer means urges the successively formed folds on the textile web into the web transport passage, an adjustment of the distance between the folding means and the retainer means can result in an adjustment of the amount of the textile web being transported, thereby making it possible to adjust the height of each of the successively formed folds on the textile web. Accordingly, it may be possible for the machine to provide a corrugated textile web product having a number of folds of any desired height. Also, since the textile web can be corrugated to provide the corrugated textile web product, the corrugated textile web can exhibit a substantially increased resistance to compression in a direction across the thickness thereof. In addition, the orientation of the fibers used in the textile web is, when the textile web is processed to the corrugated textile web product, changed to conform to the direction of thickness of the corrugated textile web product, the latter can have an increased thickness while exhibiting a required elasticity. The textile web may be corrugated or gathered by the machine over a considerable range of possible thickness and, therefore, the machine need not be assembled in a bulky size. Also, during the preferred passage of the corrugated textile web product through the web transport passage, a compressive force acts on the consecutive folds of the textile web from above and also from a lateral direction and, therefore, the folds tend not to be deformed, making it possible to manufacture the corrugated textile web products of substantially uniform quality. BRIEF DESCRIPTION OF THE DRAWINGS In any event, the present invention will become more clearly understood from the following description of embodiments thereof, when taken in conjunction with the accompanying drawings. However, the embodiment and the drawings are given only for the purpose of illustration and explanation, and are not to be taken as limiting the scope of the present invention although they do show some preferred features. In the drawings, like reference numerals are used to denote like parts throughout the several views, and: Fig. 1 is a schematic side view, with a portion cut away, showing a textile web corrugating machine embodying the present invention; In Fig. 2, Figs. 2(a) to 2(c) are schematic side views showing the sequence of formation of a textile web; Fig. 3 is a schematic perspective view, on an enlarged scale, of a portion of the textile web corrugating machine, showing how a textile web is corrugated or gathered in the machine; Fig. 4 is a cross-sectional view, on a somewhat enlarged scale, taken along the line IV-IV in Fig. 1; Fig. 5 is a side sectional view of another portion of the textile web corrugating machine showing the position of a presser plate and the inclination of a support table; In Fig. 6, Figs. 6(a) to 6(h) are diagrams showing the sequence of corrugation or gathering of the textile web which takes place in the textile web corrugating machine, and Figs. 7 to 9 are schematic side sectional views of the conventional textile webs already discussed. Referring first to Fig. 1, a textile web corrugating machine shown therein compresses a support table 11 along which a sheet-like textile web 10 is supported in a direction shown by the arrow A1. The textile web 10 may be a non-woven fabric comprising, as shown in Fig. 2(a), non-woven fibers 10a bonded together by a fiber binder 10b and has a thickness ℓ preferably within the range of 8 to 30 mm although not limited thereto. Material for the non-woven fibers 10a may be chosen from, for example, natural cotton, rayon and high-melting point fibers of polyester or polypropylene resin. The fiber binder 10b used in the textile web 10 may be low-melting point synthetic fibers such as, for example, thermally fusible compound fibers of polypropylene resin known as "ES Fibers" manufactured and sold by Chisso Kabushiki Kaisha of Japan, polyester fiber known as "TBS Fibers" manufactured and sold by Teijin Kabushiki Kaisha of Japan. The fiber binder 10b is so processed as to represent fibers each having a length generally within the range of 38 to 160 mm. In the practice of the present process, the fibers may be oriented either in two dimensions or in three dimensions. As a method of making the textile web 10, any one of a method of mixing the non-woven fibers 10a with the binder 10b and a method of spreading the binder 10b in the form of a powder over the non-woven fibers 10a may be employed. It is, however, to be noted that Fig. 2(b) illustrates the textile web 10 having been corrugated over the length thereof and Fig. (c) illustrates the corrugated textile web 10 having been heat-treated to provide a final corrugated web product 10c. The web corrugating machine also comprises a folding unit 20 and a retainer unit 30 both supported above the support table 11 and in opposing or face-to-face relationship as shown in Fig. 1. All of the support table 11, the folding unit 20 and the retainer unit 30 are mounted on and supported by a machine frame structure generally identified by 12. As best shown in Figs. 1 and 3, the folding unit 20 comprises a folding plate 21 extending generally over a width of the textile web 10, at least one vertical cylinder 22 for driving the folding plate 21 up and down, i.e., in a generally vertical direction perpendicular to the direction A1 of transport of the textile web 10, a slide block 24 for the support of the vertical cylinder 22 thereon, at least one horizontal cylinder 23 for driving the slide block 24 and, hence, the vertical cylinder 22 generally in a horizontal direction parallel to the direction A1 of transport of the textile web 10, and a fixed support block 25 for the support of the horizontal cylinder 23. As best shown in Fig. 3, the folding plate 21 has upper and lower side portions lying at an angle relative to each other so as to assume a generally L-shaped cross-section, with the lower side portion 21a lying in a plane substantially perpendicular to the direction A1 of transport of the textile web 10. The lower side portion 21a of the folding plate 21 has a lower side edge 21b having a generally J-shaped cross-section and adapted to be brought into contact with the textile web 10 being transported over the support table 11. The lower side edge 21b (continuous with the plate 21 through the lower side portion 21a) has a plurality of spikes 23 secured thereto so as to protrude outwardly therefrom, said spikes 23 being operable to avoid any possible slip of the lower side edge 12b relative to the textile web 10 being transported in the direction A1. The folding plate 21 is adapted to be driven by the vertical cylinder 22 so as to move in downward and upward directions shown by the arrows B1 and B2, respectively, which are substantially perpendicular to the direction A1 and to the general plane of web 10, and to be driven by the horizontal cylinder 23 so as to move in forward and rearward directions shown by the arrows A1 and A2, respectively, which are parallel to the direction A1 of transport of the textile web 10. More specifically, the selective extension and retraction of a piston rod of the vertical cylinder 22 result in the movement of the folding plate 21 in the downward and upward directions B1 and B2, respectively, and similarly, the selective extension and retraction of a piston rod of the horizontal cylinder 23 result in the movement of the folding plate 21 in the forward and rearward directions A1 and A2, respectively. When the folding plate 21 is moved in the downward direction B1, the lower side edge 21b thereof is brought into contact with the textile web 10 and, therefore, the subsequent movement of the folding plate 21 in the forward direction A1 effected by the extension of the piston rod of the horizontal cylinder 23 results in the formation of a single fold on the textile web 10. As the folding plate 21 is repeatedly moved by a combined operation of the vertical and horizontal cylinders 22 and 23 so as to depict a generally rectangular trajectory as shown in a right hand portion of Fig. 1, the textile web 10 can be progressively corrugated with plural folds distributed along the length of the textile web 10 as shown. As will be subsequently described, during the formation of each fold on the textile web 10, the textile web 10 being transported is held still by the action of the retainer unit 30 in cooperation with a back-up compressor unit. The retainer unit 30 comprises a retainer member 31 extending generally over the width of the textile web 10 and substantially parallel to the folding plate 21 of the folding unit 20, at least one vertical cylinder 32 operable to move the retainer member 31 up and down in a direction generally perpendicular to the direction A1, and to the general plane, of web 10, a slide block 34 for the support of the vertical cylinder 32 thereon, a horizontal cylinder 33 operable to move the slide block 34 and, hence, the vertical cylinder 32 selectively in forward and rearward directions parallel to the direction A1 of transport of the textile web 10, and a fixed support block 35 for the support of the horizontal cylinder 33. The retainer member 31 is positioned at a location spaced a distance from the folding plate 21 and has a lower side edge to which a plurality of generally U-shaped fingers 31a are secured so as to extend downward towards the textile web 10 being transported along the support table 11. The U-shaped fingers 31 are equidistantly spaced from each other over the width of the textile web 10 and extend into respective spaces defined by a generally comb-shaped guide 41 as will be described later. As is the case with the folding plate 21, the retainer member 31 is adapted to be driven by the vertical cylinder 32 so as to move in downward and upward directions shown by the arrows B1 and B2, respectively, which are substantially perpendicular to the direction A1 of transport of the textile web 10, and to be driven by the horizontal cylinder 33 so as to move in forward and rearward directions shown by the arrows A1 and A2, respectively, which are parallel to the direction A1 of transport of the textile web 10. More specifically, the selective extension and retraction of a piston rod of the vertical cylinder 32 result in the movement of the retainer member 31 in the downward and upward directions B1 and B2, respectively, and similarly, the selective extension and retraction of a piston rod of the horizontal cylinder 33 result in the movement of the retainer member 31 in the forward and rearward directions A1 and A2, respectively. When the retainer member 31 is moved in the downward direction B1, the U-shaped fingers 31a carried by the retainer member 31 are engaged in between the neighboring folds 10c on the textile web 10 to facilitate the formation of the fold 10 c on one side thereof adjacent the folding plate 21. The movement of the retainer member 31 effected by a combined operation of the vertical and horizontal cylinders 32 and 33 so as to depict a generally rectangular trajectory similar to that depicted by the movement of the folding plate 21 takes place in concert with that of the folding plate 21 as described later. The back-up compressor unit comprises a plurality of generally rectangular presser plates 42 positioned along a passage 60 for the transport of the textile web therethrough in side-to-side abutting fashion each of said rectangular presser plates 42 extending in a direction parallel to the widthwise direction of the textile web 10. One of the presser plates 42 adjacent the folding plate 21 has a free side edge 42a to which the comb-shaped guide 41 having a plurality of equally spaced guide fingers is hingedly connected by means of a hinge 45. The comb-shaped guide 41 is pivotable about the hinge 45 relative to the presser plate 42 adjacent the folding plate 21 and is normally urged by a coil spring 46, disposed between the comb-shaped guide 41 and a portion of the machine frame structure 12, to a pressing position at which the comb-shaped guide 41 is spaced a predetermined distance d upwardly from the support table 11 while pressing the folds 10a formed on the textile web 10 so that the folds 10c being formed on the textile web 10 can be smoothly guided into the gap between the comb-shaped guide 41 and the support table 11. As described above, the presser plates 42 are spaced the distance d upwardly from the support table 11. As best shown in Fig. 4, each of those presser plates 42 has its opposite ends 42c and 42d retained by respective ones of plural holders 39. Each of the holders 39 for each end 42c and 42d of each presser plate 42 comprises a screw rod 48 having its opposite ends rigidly secured to different portions of the machine frame structure 12 and extending in a direction perpendicular to the direction A1, and to the plane of the web 10, through a respective bracket 47 rigidly secured to the associated end 42c and 42d of the respective presser plate 42; a pair of ring nuts 49 threadingly mounted on the screw rod 48 and positioned above and below the bracket 47; and a pair of coil springs 50 mounted on the screw rod 48 and positioned between the ring nuts 49 and the bracket 47. Accordingly, turning any one of the ring nuts 49 to adjust the compressive force exerted by the associated coil spring 50 positioned between such one of the ring nuts 49 and the bracket 47 can result in an adjustment of the distance d defined between the respective presser plate 42 and the support table 11. As best shown in Fig. 5, one of the presser plates 42 adjacent the support table 11 is upwardly inclined at a predetermined angle ϑ relative to the horizontal plane and, similarly, the support table 11 is inclined upwardly at the same angle ϑ so that the path 50 along which the textile web 10 is transported can be bent at a location corresponding to the joint between the presser plates 42 as shown in Fig. 5. Thus, it will readily be understood that the adjustment of the distance d between the presser plates 42 and the support table 11 and the distance x between the lower side portion 21a of the folding plate 21 and the U-shaped fingers 31a carried by the retainer member 31 as indicated in Fig. 6(b) can result in an adjustment of the height of each fold 10c being formed on the textile web 10 and, hence, the overall thickness of the eventually formed corrugated product, so that the successive folds 10c formed in the textile web 10 can be smoothly transported towards a mesh conveyor unit as will be described later. Referring still to Fig. 5, delivery plates 75 and 76 are connected to a forward edge 42b of one of the presser plates 42 remote from the support plate 11 and a forward edge 11b of the support table 11. The delivery plates 75 and 76 serve to guide the textile web 10, having been corrugated, towards a delivery gap between upper and lower mesh conveyors 43 and 44 without the corrugated textile web 10 being deformed, said upper and lower mesh conveyors 43 and 44 being best shown in Fig. 1. As shown in Fig. 1, each of the mesh conveyors 43 and 44 comprises a generally endless perforated belt trained between drive and driven rolls. A lower run of the perforated belt of the upper mesh conveyor 43 is normally urged towards the corrugated textile web 10 by means of spaced apart urging rolls 55 and 56 positioned inwardly of such lower run of the perforated belt of the upper mesh conveyor 43 and extending in a direction parallel to the widthwise direction of the textile web 10. Positioned between the urging rolls 55 and 56 are a heating furnace 80 and a cooling unit 81 at upstream and downstream sides, respectively, with respect to the direction A1 of transport of the textile web 10. The heating furnace 80 is of a construction comprising a source of heated air 80a applied to the corrugated textile web 10 to fuse the binder 10b contained therein thereby to bind the fibers 10a (Fig. 2(a)) together. The temperature of the heated air 80a is so selected as to be higher than the melting point of the binder 10b used and lower than the melting point of the non-woven fibers 10a and, for example, within the range of 60 to 180°C, and preferably within the range of 140 to 160°C. The cooling unit 81 is positioned downstream of the heating furnace 80 and is operable to apply a cooling air 81a to the heat-treated corrugated textile web to facilitate hardening or curing of the fused binder to fix the folds 10c. Thus, it will readily be seen that, when the corrugated textile web 10 having been so heat-treated in the manner as described above during the passage thereof through the heating furnace 80 is passed through the cooling unit 81, the folds 10c on the textile web 10 can be fixed to provide the finally corrugated textile web product. It is to be noted that the cooling which takes place during the passage of the corrugated textile web 10 through the cooling unit 81 is effective to facilitate an easy separation of the corrugated textile web 10 from any one of the mesh conveyors 43 and 44. While the textile web corrugating machine is so constructed as hereinbefore described, it operates in the following manner. The operation of the machine will now be described with particular reference to Fig. 6. In the first place, as shown in Fig. 6(a), an attendant worker has to manually fold a leading end portion of the textile web 10 to form at least one fold and then to place a weight 90 on a leading end. The weight 90 is used to avoid any possible stretch of that leading end portion of the textile web 10 which has once been manually folded. After the placement of the weight 90 in the manner as hereinabove described, the cylinders 22, 23, 32 and 33 have to be actuated to perform successively such operations as shown in Figs. 6(b) to 6(h). More specifically, starting from a condition shown in Fig. 6(b) in which the folding plate 21 is lowered to bring the side edge 21b into contact with the textile web 10 with the spikes 23 driven thereinto, the folding plate 21 is moved in the forward direction to form a single fold R. At this time, the U-shaped fingers 31a of the retainer member 31 have been lowered to facilitate the formation of a portion of the textile web 10 between the folding plate 21 and the U-shaped fingers 31b to be folded as shown by R as shown in Fig. 6(c). Thereafter, as shown in Figs. 6(d) to 6(f), the U-shaped fingers 31a fast with the retainer member 31 are upwardly shifted as shown in Fig. 6(d) and then driven in the rearward direction as shown in Fig. 6(e) to move over the fold R being formed, finally lowered again to touch the rear root of the fold R,adjacent the folding plate 21 as shown in Fig. 6(f). During this process shown in Figs. 6(d) to 6(f), the folding plate 21 is held in the lowered position with the spikes 23 driven into the textile web 10. After the condition shown in Fig. 6(f) has been attained, that is, after the U-shaped fingers 31a fast with the retainer member 31 have been lowered to touch that one of the roots of the fold R adjacent the folding plate 21, the folding plate 21 is upwardly shifted with the spikes 23 disengaged from the textile web 10, as shown in Fig. 6(g), and is then driven in the rearward direction and, at the same time, the U-shaped fingers 31a fast with the retainer member 31 are driven in the forward direction as shown in Fig. 6(h). The forward movement of the U-shaped fingers 31 rigid with the retainer member 31 shown in Fig. 6(h) results in a compression of the fold R against the previously formed fold or folds with the U-shaped fingers 31 entering respective spaces defined between the guide fingers of the comb-shaped guide 41, allowing the compressed folds to move into the gap between the comb-shaped guide 41 and the support table 11; the up-turned rear guide edge assisting. By repeating the sequence of operations described above, the textile web 10 can be continuously corrugated to provide the corrugated textile web product. By way of example, with a textile web corrugating machine as described herein, a textile web 10 having a thickness of 10 mm can be corrugated to provide a corrugated product having an overall thickness of 30 mm or greater. Thereafter, the textile web 10 so corrugated is transported along the web transport passage 60 in compressed fashion and is subsequently passed through the heating furnace 80 and then through the cooling unit 81 with the folds 10c consequently fixed, thereby completing the manufacture of the corrugated textile web product. Thus, the folding plate 21 is utilized to corrugate the textile web 10 while the retainer member 31 is utilized to force each fold 10c being formed into the web transport passage 60. Accordingly, the adjustment of the distance between the folding plate 21 and the retainer member 31 can result in an adjustment of the amount of the textile web 10 which is forced into the web transport passage whereby the height of each fold formed on the textile web 10 can be adjusted. This means that the machine is effective to provide the corrugated textile web product having a number of folds of any desired height. Also, since the textile web 10 is processed to provide a corrugated textile web product, the product can exhibit a substantially increased compressive strength in a direction across the thickness thereof. In addition, the orientation of the fibers used in the textile web is, when the textile web is processed to a corrugated textile web product, changed to conform to the direction of thickness of the corrugated textile web product, the latter can have an increased thickness while exhibiting a required elasticity. The textile web 10 to be corrugated or gathered by the machine as described above may have any thickness and, therefore, the machine need not be assembled in a bulky size. Also, during the passage of the corrugated textile web product through the web transport passage 60, a compressive force acts on the consecutive folds on the textile web from above and also from a lateral direction and, therefore, the folds 10c will not be deformed, making it possible to manufacture the corrugated textile web products of substantially uniform quality. Furthermore, the adjustment of the distance d and also that of the pressing pressure exerted by the retainer member 31 can result in an adjustment of the compressive force acting so as to press the folds 10c of the textile web 10. Therefore, prior to the folds 10c being fixed during the passage thereof through the heating furnace 80, the folds 10c can be retained in position without being deformed thereby to adjust the density of fibers in a direction parallel to the direction of transport of the textile web 10. Thus, from the foregoing description of an embodiment of the present invention, the textile web corrugating machine is provided with the folding plate operable to corrugate the textile web to form the folds thereon and the retainer member operable to force the corrugated portion of the textile web into the web transport passage. Therefore, the corrugated textile web product having any desired thickness can be readily obtained. Also, since the folding of the textile web to form the folds renders the eventually corrugated textile web to exhibit an increased resistance to compression in a direction across the thickness thereof and, also, since the orientation of the fibers contained in the textile web changes from the directions parallel to and transverse to the lengthwise direction of the textile web to the direction conforming to the thickness of the textile web, the eventually corrugated textile web product having an increased thickness and also having a desired elasticity can be obtained. Yet, since the compressive force is applied from above and also from the lateral direction to the folds formed on the textile web during the passage thereof through the web transport passage, any possible deformation of the folds on the textile web can be avoided, thereby making it possible to provide the corrugated products of substantially uniform quality. Although the present invention has been fully described in connection with the preferred embodiment thereof with reference to the accompanying drawings which are used only for the purpose of illustration, those skilled in the art will readily conceive numerous changes and modifications. For example, although in the foregoing illustrated embodiment reference has been made to the single textile web, the machine may be able to accommodate a plurality of textile webs laminated or positioned one above the other. Where the textile webs in a multi-layered structure are employed as a material for, for example, an air filter, the fibers in the respective textile webs may have different diameters so that relatively large particles can be trapped by the fibers of relatively large diameter and small particles can be trapped by the fiber of relatively small diameter, thereby enhancing the filtering efficiency. Also, the corrugated textile web product manufactured by the use of the machine according to the present invention can be used not only e.g. as air filtering material for trapping particles floating in the air, but also as an aqueous filtering material for trapping particles contained in a liquid medium or for filtering water in a swimming pool. Yet, the corrugated textile web product can also be used as a cushioning material utilizable in a chair, sofa, bed or the like. Where the corrugated textile web produce is enclosed in a textile bag, it can be used as a bedding sheet.

Claims: A textile web corrugating machine having a transport path, along which a textile web (10) to be corrugated is transported in a downstream direction; an elongate folding element (21) extending transversely over the transport path, and a first drive (22,23,24) to move the elongate folding element (21) in a repeated cycle of movement relative to the transport path, thereby to engage the textile web (10) and form successive transverse folds therein to corrugate the web; and an elongate retainer element (31) extending transversely over the transport path adjacent and downstream of the folding element (21), to guide the transverse folds of textile web into a downstream passage portion of the transport path which has means (42) for pressing the corrugated web; characterised in that (a) a support table (11) is provided to support the textile web (10) along at least an upstream portion of the transport path, the folding element (21) and the retaining element (31) being disposed over the support table (11); (b) the first drive (22,23,24) is adapted to drive the folding element (21) in a cycle of movement involving successively movement towards the support table (11) to engage the textile web (10) thereon, movement downstream along the support table (11) to form a transverse fold of the thus-engaged textile web (10), and movement away from the support table (11) and upstream to disengage from the textile web (10) and return to complete the cycle, and in that (c) a second drive (31,32,33) is provided to drive the retainer element (31), in synchronised relation with the folding element (21), in a cycle of movement involving successively movement towards the support table (11) to engage the textile web (10) upstream of the transverse fold formed by the folding element (21), movement downstream along the transport path (11) to urge the transverse fold towards the downstream passage portion of the transport path, and movement away from the support table (11) and upstream to disengage from the transverse fold and return to complete the cycle. A textile web corrugating machine according to claim 1 in which the first drive has a drive cylinder (22) for driving the folding element (21) perpendicular to the support table (11), and another drive cylinder (23) for driving the folding element (21) parallel to the support table (11) along the transport path. A textile web corrugating machine according to claim 1 or claim 2 in which the second drive comprises a drive cylinder (32) for driving the retainer element (31) perpendicular to the support table (11), and another drive cylinder (33) for driving the retaining element (31) parallel to the support table (11) along the transport path. A textile web corrugating machine according to any one of the preceding claims having a transversely-extending guide (41) above the support table (11) at the entrance to the downstream passage portion of the transport path, adjacent the retainer element (31), the guide (41) being pivotable towards and away from the textile web under the influence of a spring (46) urging it towards the textile web, to compress and guide the transverse folds into the passage portion as they are urged by the retainer element (31). A textile web corrugating machine according to any one of claims 1 to 3 having a transversely-extending guide (41) above the support table (11) at the entrance to the downstream passage portion of the transport path, adjacent the retainer element (31), the guide (41) having a series of transversely-spaced fingers pointing upstream, and the retainer element (31) having a complementary series of transversely-spaced fingers (31a) pointing towards the support table (11) to engage the transverse folds of the textile web (10), such that the fingers (31a) of the retainer element (31) pass between the fingers of the guide (41) as the retainer element (31) moves. A textile web corrugating machine according to any one of the preceding claims, comprising heating means (80), downstream of the folding element (21) and retaining element (31), for heating the corrugated textile web to bind it. A textile web corrugating machine according to any one of the preceding claims in which the pressing means comprises presser plates (42) for pressing on corrugated web in the downstream passage portion of the transport path. A textile web corrugating machine according to any one of the preceding claims in which the folding element (21) has an edge (21b) with spikes (23) to engage the textile web (10) without slip. A textile web corrugating machine according to any one of the preceding claims in which the size of said movement of the folding element (21) downstream along the support table (11) is adjustable to enable variation in the size of the transverse folds formed in the textile web. A method of corrugating a textile web, comprising transporting the textile web (10) along a transport path in a downstream direction; corrugating the textile web by driving an elongate folding element (21), extending transversely over the transport path, in a repeated cycle of movement relative to the transport path to engage the textile web (10) and form successive transverse folds therein; guiding the transverse folds of textile web into a downstream passage portion of the transport path, using an elongate retainer element (31) extending transversely over the transport path adjacent and downstream of the folding element (21) to engage the transverse folds, and pressing on the corrugated web in the downstream passage portion; characterised (a) in that along at least an upstream portion of the transport path, the textile web is supported on a support table (11) over which the folding element (21) and the retainer element (31) are disposed; (b) in that the cycle of movement in which the folding element (21) is driven involves successively movement towards the support table (11) to engage the textile web, movement downstream along the support table (11) to form a transverse fold in the textile web, and movement away from the support table (11) and upstream to disengage from the textile web (10) and return to complete the cycle, and (c) in that the retainer element (31) is driven, in synchronised relation with the folding element (21), in a cycle of movement involving successively movement towards the support table (11) to engage the textile web (10) upstream of the transverse fold formed by the folding element (21), movement downstream along the transport path (11) to urge the transverse fold towards the downstream passage portion of the transport path, and movement away from the support table (11) and upstream to disengage from the transverse fold and return to complete the cycle. A method according to claim 10, comprising heating the corrugated web downstream of the folding element (21) and retaining element (31), to bind it. A method according to claim 10 or claim 11 in which the textile web (10) is a non-woven fabric (10a) with a fibre binder (10b) to bind fibres thereof. A method according to any one of claims 10 to 12 in which the textile web (10) has a thickness of from 8 to 30 mm.

Inventors: YOGO TAKEYOSHI C O TAKETARO YO, YOGO, TAKEYOSHI, C/O TAKETARO YOSHIZUMI & CO. LTD., Yogo, Takeyoshi, c/o Taketaro Yoshizumi &amp; Co. Ltd.
Applicants: TAKETARO YOSHIZUMI & CO, TAKETARO YOSHIZUMI & CO.LTD.
Application year: 1990
Main classification: D04H1
IPC codes: D04H1, D06J1, D04H11