US3774273A - Needle felting apparatus - Google Patents

Needle felting apparatus Download PDF

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Publication number
US3774273A
US3774273A US00116146A US3774273DA US3774273A US 3774273 A US3774273 A US 3774273A US 00116146 A US00116146 A US 00116146A US 3774273D A US3774273D A US 3774273DA US 3774273 A US3774273 A US 3774273A
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Prior art keywords
needle
conjugated
needles
felting
board
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US00116146A
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M Okamoto
T Hikota
K Shimizu
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Toray Industries Inc
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Toray Industries Inc
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Priority claimed from JP1444270A external-priority patent/JPS4935100B1/ja
Priority claimed from JP45014443A external-priority patent/JPS4816151B1/ja
Priority claimed from JP45061372A external-priority patent/JPS4948578B1/ja
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    • D—TEXTILES; PAPER
    • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
    • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
    • D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
    • D04H1/40—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties
    • D04H1/44—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties the fleeces or layers being consolidated by mechanical means, e.g. by rolling
    • D04H1/46—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties the fleeces or layers being consolidated by mechanical means, e.g. by rolling by needling or like operations to cause entanglement of fibres
    • D04H1/48—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties the fleeces or layers being consolidated by mechanical means, e.g. by rolling by needling or like operations to cause entanglement of fibres in combination with at least one other method of consolidation
    • D—TEXTILES; PAPER
    • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
    • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
    • D04H18/00—Needling machines
    • D04H18/02—Needling machines with needles

Definitions

  • MIYOSHI OKAMOTO TOYOHIKO HIKOTA Fig. 38 BY KITAO SHIMIZU ATTORNEYS.
  • the present invention relates to a needle felted fabric having a homogeneous internal structure, and to the fabric, the method, the needle, and the needle punching machine used.
  • the needle felted fabric at least 60 percent of the fibers which penetrate the other fibers do so either individually or as a group and are composed of from 2 to 3 fibers.
  • the needle felted fabric of the present invention can be used advantageously as a base for artificial leather and has other uses described in further detail hereinafter.
  • needle punched felted fabric has hitherto been used as a base material. It is usually produced by punchinga random web or cross lapped web of fibers by using a needle punching machine wherein needles having a great number of barbs or having a great depth of barbs are fixed on a needle board, and are reciprocated back and forth through a mass or web of fibers to punch certain of the fibers through others.
  • conventional needle felted fabric can be used only as a base material for textiles where great uniformity is not required, such as in carpets or rugs, for example.
  • Conventional needle felted fabric is not at all satisfactory as a base material for high grade artificial leather, for example.
  • textile material is adheredto abase material made of needle felted fabric, and porous.
  • polyurethane is coated thereon.
  • the product is an artificial leather of high directional anisotropy, excessive hardness, and insufficient elongation, and the resulting artificial leather cannot be used easily for making shoes. Also, the resulting shoes do not conform well to the shape of the feet, but cause localized rubbing and aggravation.
  • the present invention provides needle felted fibrous sheets which are advantageous for producing artificial leathers having a velour finish, or a suede like finish, and/or a finish of a nubecula type having a uniform napped surface, or for producing artificial leather having a grainy surface of excellent surface smoothness.
  • An object of the present invention is to produce a needle felted fabric having a uniform penetrating fiber structure which overcomes the drawbacks inherent in conventional needled fabric used as a base material for artificial leather.
  • the needle felted fabric has the characteristic that at least 60 percent of the penetrating fiber groups are composed of from 1 to 3 fibers, in other words, either individual fibers or pairs or groups of three.
  • the invention further relates to a felting needle having a fiber hooking coefficient which is below 3, and the diameter of the lateral cross-section of the blade is from 0.30 to 0.54 mm, (preferably from 0.38 to 0.51 mm).
  • the invention further relates to a felting needle wherein the catching modulus of the fiber is below 3, and the lateral cross-section of the blade is substantially a regular triangle, and the height thereof is from 0.28 to 0.61 mm, preferably from 0.35 to 0.56 mm.
  • the present invention relates to a conjugated needle wherein at least two felting needles, each of which has preferably less than three barbs, are united in such a manner that the interval between the points of the needles is from 300 to 5,000 microns, preferably per plates and in the bed-plates, the distance between the outermost surface of said bundled needles and the wall surface of the corresponding needle hole is from 0.5 to 9 mm, preferably from 2 to 5 mm.
  • the felting needle of the present invention can be used advantageously in forming such a conjugated needle, and this conjugated needle can be used advantageously in the needle punching machine.
  • FIG. 1 is an outline of the side view of part of a conventional needle loom
  • FIG. 2 is a side view of a. conventional needle
  • FIG. 3 is an enlarged view of the barb portion of the needle of FIG. 2;
  • FIG. 4 is a vertical cross-sectional view of conventional needle felted fabric, taken as indicated by the lines and arrows IVIV which appear in FIG. 1;
  • FIG. 5 is a cross-sectional view of the needle felted fabric, taken as indicated by the lines and arrows VV which appear in FIG. 4;
  • FIGS. 6 are diagrams showing various conditions of the needle punched fibers in conventional needle felted fabric
  • FIG. 8 is a lateral cross-sectional diagram showing needle felted fabric according to the present invention.
  • FIG. 9 is a lateral view of the fabric of FIG. 8;
  • FIGS. 10 are diagrams showing various conditions of the needle punched fibers in fabric according to the present invention.
  • FIG. 11 is a diagram showing the surface configuration attained when needled fabric according to the present invention is processed as the base material for artificial leather;
  • FIG. 12 is a lateral cross-section of a typical islands-in-a-sea type filament which is preferably present in needled fabric according to the present invention.
  • FIG. 13 is a longitudinal cross-section of the filament shown in FIG. 12;
  • FIGS. 14 and 15 are lateral cross-sections of other em-bodiments of islands-in-a-sea type filaments
  • FIG. 16 is a diagram showing the barb portion of a needle for illustrating the fiber hooking coefficient of a needle
  • FIGS. 17 through 21 are the diagrams showing side views of various modifications of the composite needle of the present invention.
  • FIGS. 24 29 are sectional views taken internally in needle punched looms having conjugated needles of various types
  • FIG. 31 is a diagram showing, in side view, a part of a needle loom according to the present invention.
  • FIG. 32 is a ground plan showing the arrangement of the cranks of the needles provided on a needle board of a single needle loom;
  • FIGS. 33 and 34 are ground plans showing arrangements of the cranks of needles provided on a needle board of a needle loom according to the present invention.
  • FIGS. 36A and B are diagrams showing how two arrangements of needles in a needle loom according to the present invention are carried out
  • FIGS. 37A and B are diagrams showing positional relations of the cranks and barbs of the respective needles, FIG. 37A showing a conventional needle and FIG. 31B showing a needle according to the present invention; FIG. 37 C is a diagram showing side view of FIG.37B.
  • FIGS. 40 45 are views in perspective showing various forms of adaptors for conjugated needles according to this invention.
  • FIG. 1 is a diagram showing part of a conventional needle punching machine; felting needles 2 are planted on the needle board 1, and a board 3 is provided on the upper surface of needle board 1.
  • the conventional barbs which may be of the kick-up type or of the non-kick-up type, have deep and large throats l6, and as is shown in FIG. 3 the throat depth D, the throat length L and undercut angle (alpha) are designed in such a manner that a large number of fibers can be hooked at once with only one barb with one punch of the needle. Generally speaking, about 5 to 16 fibers 15 are hooked with one barb 14.
  • FIG. 4 shows the vertical cross-section of a typical needle punched fabric produced by using a conventional needle punching machine as just described.
  • the respective penetrating fiber groups 18 formed in the fibrous web 17 with one needle is composed of extremely large numbers of fibers, and when the whole needled fabric is observed, the local concentration of the penetrated fibers is apparent.
  • FIGS. 6A through D shows the napped condition of a product resulting from the condition shown in FIGS. 4 and 5 in a product which was doped with an elastic high polymer solution, and the surface of which was subsequently buffed.
  • FIG. 6 the upper and lower dotted lines 19 and 20 represent the upper and lower surfaces of the needled fabric respectively.
  • FIG. 6A shows how a great number of fibers 21 are all together hooked, curved and bound by the penetration of the needle through the thickness of the felt.
  • FIG. 6B shows the condition where, after the step of FIG. 6A has been completed, the fiber bundle which has been curved by reason of the mechanism of the needle, is cut at the curved end of the bundle or the neighborhood thereof.
  • FIG. 6C shows the condition in which a great number of fibers 21 are bound at various depths, each in the form of a local fiber group, across the thickness of the felt, by the operation of a needle having multiple barbs.
  • FIG. 6D shows the condition in which after the state shown in FIG. 6A has been formed, a typical bundled fiber group 18 is projected through and beyond the surface of the felt by the movement of the needle. This is an example of remarkably poor needle punching attained in accordance with the prior art.
  • FIG. 7 shows the conventional needled fabric processed as a base for artificial leather. Great numbers of penetrating fibers 21 are concentrated locally as heretofore described.
  • the needled fabric of the present invention has no such drawback and adapts excellently for artificial leather of high grade.
  • the fibers 31 are the filaments which are associated substantially all in the same direction before they are subjected to needle punching.
  • the fibers 32 are hooked with a needle moving substantially perpendicular to the web and penetrate substantially in the perpendicular direction into the web which is formed of a great number of fibers 31.
  • a needle moving substantially perpendicular to the web and penetrate substantially in the perpendicular direction into the web which is formed of a great number of fibers 31.
  • from 1 to 3 monofilaments are caught by each individual needle and accordingly penetrate as a group of from 1 to 3 monofilaments.
  • FIG. 9 is a diagram showing the lateral cross-section of the embodiment of FIG. 8, and shows that the penetrating fibers 32 actuated by a single needle can be observed predominantly as small groups of one, two or three filaments injected as groups between the great numbers of penetrated fibers 31.
  • the number of the fibers which are inserted and penetrated with a single needle are counted in accordance with the following method.
  • the upper and lower dotted lines 36 and 37 show the upper and lower surfaces of the needled fabric.
  • both ends of one fiber 33 are almost horizontal on the surface of the sheet or in the neighborhood thereof, as is shown in FIG. 10A, and the fiber extends crosswise and is bent upon itself inside the sheet;
  • the number of penetrating fibers is counted as one; the number of fibers in the penetrating fiber group formed by one needle is one.
  • the number of penetrating fibers is counted to be three.
  • counting is carried out inv accordance with the method described above.
  • FIG. 9 is a diagram showing a needled fabric according to this invention as is shown in FIGS. 8 and 9, which has been processed into a base material for artificial leather, and the number of penetrating fibers 32 formed by one needle is from 1 to 3, and therefore the nap of the needled fabric of this invention is remarkably uniform without penetrating the locally concentrated nap condition as in the conventional products such as the one appearing in FIG..7.
  • the denier of the fiber to be used in the present invention is preferably from about 0.5 to 30, more preferably about 0.8 to 10.
  • the staple length of the fiber to be used in the present invention is preferably about 15 120 mm, more preferably about 25 84 mm.
  • natural filaments or artificial filaments can be used, but more in particular, the advantageous features of the present invention can be attained with use of artificial fibers whose felting effect is generally inferior to natural fibers. More in particular, filaments of the islands-in-a-sea type are especially preferable.
  • An islands-in-a-sea type filament is a filament formed from two types of high molecular weight polymers; when the lateral cross-section of such a filament is observed, there is a portion which forms the sea which is composed of one of these high polymers, and the islands are composed of the other polymer. The respective islands are dispersed in the sea, and this lateral cross-sectional condition is continuously present along the length of the filament.
  • An islands-in-a-sea type filament in which the number of islands is more than 10 is especially preferred.
  • Typical high molecular weight polymers for forming said island include polyamides, polyesters, polyolefins, polyacrylonitriles or polyurethanes and such polymers. Also copolymers are preferably used.
  • the high polymers for forming the sea include polystyrene and copolymers thereof, polymethylmethacrylate and copolymers thereof, polyvinyl alcohol and the like.
  • FIG. 12 shows the lateral cross-section of one form of islands-in-a-sea type filament
  • FIG. 13 shows its longitudinal cross-section.
  • the islands-in-a-sea type filament 41 is composed of sea forming portion 42 and islands forming portions comprising a great number of islands 43 dispersed in said sea forming portion 42.
  • the above mentioned condition substantially continues along the length of the filament as is shown in FIG. 13, and in this respect, the islands-in-a-sea type filament of this invention is different from the filament obtained by spinning a blend of two kinds of polymers as is generally known to those skilled in the art.
  • FIG. 14 is a diagram showing an enlarged view of the lateral cross-section of an embodiment of another islands-in-a-sea type filament. It differs from that of FIG. 12 in that the islands 43 are relatively more thickly dispersed in the sea forming portion 42 inside the filament 41.
  • the islands-in-a-sea type filament of FIG. 15 is especially adapted for remarkably reducing the surface non-uniformity similar to an orange peel which appears in making shoes when it is used as a base material for artificial leather.
  • the islands-in-a-sea type filament can be produced in accordance with the method described in the specification of British Patent No. 1,171,843, or of US. Pat. No. 3,531,368, or modifications.
  • the islands-in-a-sea type filaments according to this invention are hooked on a needle as one filament when they are subjected to the needle punching process, and are caused to penetrate but the island forming portions are caused to remain as separate fine fibers by removing the sea forming portion of the filament after having been incorporated into the needled fabric, and the island forming portion takes on a structure very similar to the collagen of natural leather.
  • an islands-in-a-sea type filament great numbers of fine filaments are present in one filament, but in counting the number of fibers present as the penetrating fibers which are tangled according to this invention, the total number of islands-in-a-sea type filaments is counted as the number of the penetrating fibers.
  • needle punching is effected by using a felting needle having a diameter from about 0.30 to 0.54 mm, preferably from about 0.38 to 0.51 mm, when the lateral cross-section of the blade portion is circular, and the fiber hooking coefficient is below 3, or by using a felting needle of equilateral triangle cross-section wherein the height or altitude of the triangle (the distance from any apex along a line perpendicular to the opposite base) is from about 0.28 to 0.61 mm, preferably from about 0.35 to 0.56 mm.
  • fiber hooking coefficient refers to the number of fibers hooked with all the barbs whose undercut ends are positioned on the blade portion within 8 mm from the undercut end of the barb closest to the needle point of one needle, as the starting point.
  • FIG. 16 is an enlarged view of the blade portion of a needle preferably used in this invention.
  • a line 54 is drawn from the end 52 of the undercut portion of the barb 51 to the center line 53, the number of fibers within the region 55 within the space defined by said line 54 and the internal wall of the barb 51 represents the fiber hooking coefficient of one barb 51.
  • the angle 45 is selected for good reason.
  • the needle In carrying out needling punching, the needle is inserted into the fibrous fabric at a considerable speed.
  • any fibers outside the area 55 do not take part in the tangling after the space 55 defined by said 45 line 54 has been filled.
  • the distance of 8 mm from the starting point has been selected because when fibers are hooked on a barb close to the needle point, it becomes difi'icult for a barb located far from the needle point to hook fibers, and it has been found from many experiments that the barbs beyond 8 mm from the starting point, hardly take part in the needling operation at all.
  • a needle density ranging from 200 to 12,000 is preferable.
  • the needled fabric When a needled fabric according to the present invention is used as the base material for artificial leather, the needled fabric is dipped into an elastic high polymer solution and coagulated and solidified.
  • suitable elastic high molecular weight polymers As examples of suitable elastic high molecular weight polymers, the following are listed:
  • polyurethane is preferable.
  • the elastic high polymer is used in solution form by dissolving the elastic high polymer in an organic solvent, for example, N, N-dimethyl forrnamide, dimethyl sulfoxide, N, N-dimethyl acetamide, N-methyl pyrrolidone, tetrahydrofuran and trimethyl phosphate, or by dispersing the elastic high polymer 17 water.
  • organic solvent for example, N, N-dimethyl forrnamide, dimethyl sulfoxide, N, N-dimethyl acetamide, N-methyl pyrrolidone, tetrahydrofuran and trimethyl phosphate
  • the preferable amount is from about 15 to 140 percent by weight of solid portion based on the amount of fibrous fabric.
  • the primaryYoungs modulus of the elastic high polymer as measured in the form of film in accordance with the dry or wet process, is preferably from about 0.09 to 3.0 kglmm and more preferably from about 0.9 to 1.7 kg/mm.
  • polyurethane When polyurethane is used, after doping it is preferably coagulated in accordance with the wet process.
  • the coagulation it is preferable to carry out the coagulation at a temperature ranging from about to 40 C, and more preferably from about to 35 C.
  • the coagulation should be terminated, and the solvent should be removed at a temperature from about 75 to 98 C.
  • the sea forming portion can be removed before or after the doping of the elastic high polymer solution.
  • a base material for artificial leather having a very smooth surface is prepared when the needled fabric, doped with elastic high polymer solution in a pseudo-set state, is subjected to a bufiing treatment.
  • the resulting base material for. artificial leather is very useful as an artificial leather having a grain surface, or napped surface.
  • the surface of the base material is very similar to the structure of natural leather; this makes it possible to produce a suede type artificial leather of high quality by bufiing.
  • a needle punching machine In a needle punching machine the durability of the needle is prolonged by using a needle of the type heretofore described because the load applied to the needle is reduced.
  • the needle bends only very slightly, and it is accordingly possible to carry out very regular punching process. It is possible to make the size of the needle punching machine larger as the load applied to the needle punching mahine is reduced. Since the load is reduced, it is possible to plant needles on the needle board at a high density in terms of needles per unit of area.
  • conjugated needle is advangeously used in producing the needled fibers of the present invention.
  • conjugated needle means that at least two felting needles, each of which preferably has less than three barbs, are united in such a manner that the interval between the needle points is about 300 to 5,000 microns, preferably from about 900 to 3,500 microns.
  • the density of the needles 2 of the needle board 1 is required to be increased, and it is necessary to increase the number stripper plate 5 in correspondence with the respective needles 2.
  • the needles are bent when punching is carried out, and therefore the diameter of the needle holes is adjusted to be much larger than the diameter of the needles; therefore there is a restriction with respect to the hole density of the needle holes 4 that may be attained on the stripper plate 5 and the bed plate 6; hen the hole density is increased beyond the applicable limitation, the bending of the plates 5 and 6 becomes pronounced.
  • the number of felting needles forming a conjugated needle according to the present invention is preferably from about 2 to 7, and in particular, from 2 to 4..
  • FIG. 17 shows conjugated felting needle; the elements 61 are blades and 62 are the barbs.
  • a conjugated needle as referred to in the specification of this invention is a needle having at least two blades 61 on one shank 63.
  • FIG. 22B is a diagram showing the cross-section across the line XXII-XXII in FIG. 17.
  • 64 is the root of each needle and 63 is the shank formed with synthetic resin or welded metal for holding the needles and fixing them in position.
  • Barbs 62 are provided on the blade portion, and the ends of the needles are sharpened in the form of a ball point, round point or heavy point.
  • the throat depth of the barbs is from about 20 to 10014,, preferably from about 20 to 65p, and in regard to the unification of needles, it is not necessary to unite the needles in parallel; a predetermined angle may be used such as the relative angle of 1 When the needles are united at a predetermined angle, the needle felted condition of the fibers formed by punching becomes random, and in view of the desire for uniformity of the felt, preferable results are obtained.
  • the needles be united at a predetermined angle, from the viewpoint of the production rate of the felting needles.
  • the unification of the needles is not restricted if sufficient durability and strength should be built into the conjugated felting needle so that it can be used without fear of being broken in the needle punching operation.
  • FIGS. 18 to 20 are diagrams showing various embodiments wherein two needles 65 are united with synthetic resin or molten metal (inclusive of welding) to form a shank
  • FIG. 21 is a diagram showing an embodiment in which three needles 65 are united similarly to form a shank 63.
  • the respective conjugated felting needles shown in FIGS. 17 through 21 have different forms of cranks 66, and in the diagrams FIG. 18 and FIG. 20, the latter conjugated felting needles have intermediate blades 67 which is a difference from the former embodiments.
  • FIGS. 22A through J are the lateral cross-sections of shank 63 of various form of conjugated felting needles, and the arrangement of needles 64 is explained by taking examples in which from 2 to 7 needles are provided.
  • FIG. 23 is a diagram showing how conjugated felting needles are provided on a needle punching machine.
  • 71 is the portion where needle board is fixed which moves up and down.
  • 72 is the needle board, and 73 is a conjugated needle.
  • 74 is the stripper plate, and 75 is the bed plate.
  • one conjugated needle is provided on one hole in the needle board 72, i.e. the hole of one conventional needle, and no special change is required, except that the diameter of the holes of the conventional needle board or plate is more or less increased.
  • FIG. 30 shows many embodiments of the form of the holes 76 and 77 provided on the stripper plate 74 and the bed plate 75. Most commonly, the form of the holes is circular.
  • barbs are provided per needle.
  • the barbs do not hook too many fibers, in particular barbs of small depth, are preferable.
  • the height of the cross-section should be preferably from about 0.28 to about 0.66 mm, preferably from about 0.28 to about 0.61 mm because the cross-section is generally a regular or equilateral triangle.
  • a fiber which has preferably from about 0.5 to about 30 denier, more preferably from about 0.8 to about 10 denier with a conjugated felting needle.
  • the throat depth of the barbs should be preferably below microns, or more preferably below 65 microns, so that uniform needling can be attained.
  • the direction of the barbs of the needle should be perpendicular to the direction in which the fibers of the web are arranged. Also, it is preferable to locate the barbs to the outside when there are many needles closely spaced, in view of the close relationship between the needles.
  • each of the fibers forming the felt i.e., each of the fibers forming the web
  • the fibers hooked by the respective barbs are concentrated into one needle
  • the conjugated felting needle of the present invention the fibers are dispersed because the needle is conjugated, and therefore there is almost no danger of the fibers being concentrated into one pin hole; because n number of needle points are respectively injected into n number of different places. Therefore, uniform and excellently needled felt can be obtained.
  • Conjugated needles are also advantageous because the whole needle is thick, and therefore the removal of the needle can be easily carried out.
  • One conjugated needle is unified with plastic, and therefore the production of the needle is simplified.
  • the needle punching efficiency is high because the number of needle points is great (or because the needle is injected in such a state that the web is being pressed).
  • the needle of the present invention is effective especially for needle punching of the islands-in-a-sea type filament, and in particular, when the sea component is a vinyl type polymer such as polystyrene, a
  • copolymer of styrene and acrylonitrile or a copolymer of styrene and methylmethacrylate.
  • the depth of the position of the barb at the needle in the present invention have no relation to the needle, and thethickness of blade can be different.
  • a conjugated needle according to the present invention is adapted for the first punch wherein the handling of a web sheet is difficult, the felt can be bound together to a considerable degree by one punch, and the punching efficiency from the second punching on can be improved.
  • FIG. 24 shows a needle punching loom having two needle boards 71, 71 each carrying conjugated needles 73, 73 having three needles.
  • the stripper plate 74 and the bed plate 75 retain the fibers as they move between them and both sets of needle boards and needles are caused to reciprocate into and out of the felted fibers; when one set of needles is in, the other set is out.
  • the opposed needles move through opposed holes in the boards 74, 75.
  • the conjugated needles are staggered so the needles of one board pass through holes that are spaced between the holes penetrated by the needles of the other needle board 71.
  • FIG. 26 is the same as FIG. 25 except that a single shafted needle opposes each conjugated needle, as shown.
  • the upper needle board 71 has conjugated needles composed of three shafts of varying lengths; the opposed needle board 71 has conjugated needles composed of two shafts of varying lengths, the shorter length shafts arranged in opposition to the longer length shafts of the opposing conjugated needle.
  • FIG. 28 the arrangement is similar to FIG. 25 except that the staggered needles are single-shaft needles instead of conjugated and the needle boards do not reciprocate; the fiber retaining plates 74, 75 are instead reciprocated toward and away from the needle boards.
  • FIG. 29 the arrangement is essentially the same as FIG. 27 except that the lengths of the needle shafts is uniform and the needle boards do not reciprocate;
  • fiber retaining plates 74, 75 are instead reciprocated toward and away from the needle boards.
  • the distance between the outermost side of the bundled needle and the wall surface of the needle holes is from about 2 to 5 mm in transferring from 2 to 20 felting needles as one bundled needle through the respective needle holes provided in correspondence to the stripper plate and bed plate.
  • the cycle of the needle punch is 500 punches/min as a normal running condition, and at the fastest it is 1200 punches/min, which is considered to be the upper limit.
  • the needle punching machine which is described in the following paragraphs overcomes the above mentioned problems.
  • the fiber needling loom of FIG. 31 is a completely new one which cannot be arrived at from the prior art, and is a needle punching machine having a great number of sets of holes each of which is made of three holes 84, and 86 respectively through the needle board 81, the stripper plate 82 and the bed plate 83. From 2 to 20 felting needles 87 are provided for each hole 84 of the needle board.
  • the cross sectional area of the shank portion of the conjugate needle is larger than the cross-sectional area of the blade portion.
  • the holes 84 fit close to the shank portion in such a manner that a space is provided between the peripheries of the holes 85 and 86 and the needles.
  • the hole 85 provided on the stripper plate as is shown by 82 in FIG. 31, is not composed of three holes but is one hole, and it is notewortny that said hole is a little larger than the hole of prior art.
  • the diameter of the hole 85 is not n times larger than the diameter of the hole of the prior art, but the diameter of the hole 85 is very slightly larger than the diameter of the hole of the prior art, and it is a remarkable characteristic of the embodiment of FIG. 31 that it is not necessary to provide a hole whose diameter is n times larger than the diameter of the hole of the prior art.
  • ' has a shank portion whose cross-sectional area is larger than the cross-sectional area of the blade portion.
  • the thickness of the shank portion be greater than that of the blade portion.
  • the value of (Thickness of shank )/(Thickness of blade) should be greater than one, and more in particular, it is preferable that the number of needles to be planted in one hole should be greater than one.
  • the throat depth of the barbs of the felting needle should be from about to 70p, and more in particular it should be from about 20 to 55;). when the number of needles to be bundled is more than three.
  • the needles bend easily, and tangled fiber flux can be formed as bundles, and the surface smoothness of the felt is decreased. Also, the needle traces and punching irregularity become pronounced; therefore it is not preferable that the throat depth should be too large. On the other hand, when the throat depth is too small, the needle punching effect becomes poor.
  • the needles whose JIS numbers range from No. 28 to No. 46, are most preferably used, and more in particular No. 34 No. 44.
  • the web When the number of needles to be planted in one hole of the needle board is more than 20, the web is pressed with too much concentration, and therefore fiber flux can be formed as bundles and a felt whose interlayer structure becomes non-uniform is apt to be produced. At the same time, the needle traces become too prominent. At the same time, when a great number of needles are inserted into one hole, the fixation of the needles becomes insufficient. Therefore, it is not preferable to provide more than 20 needles in one hole of the needle board.
  • the distance between the needles and the outer periphery of the hole when the needle is inserted most deeptly i.e., the interval between the outermost needles bundled with shanks contacted against each other and the stripper plate as well as the bed plate,- should be from about 0.5 to about 9 mm, preferably from about 2 to about 5 mm, and more preferably from about 2.5 to 4 mm.
  • the distance when the distance is less than 0.5 mm, the operation for attaching needles onto the needle board becomes difficult, and when the needles are bent slightly, they break easily.
  • the distance is more than 9 mm, the needle density is hard to increase and the strength of the respective plates is lowered; at the same time, the fiber tends to accumulate. between needles during the primary stage of needle punching, making it difficult to produce a beautiful smooth felt surface. At the same time punching efficiency is likely to be lowered. Therefore it is not preferable to make the distance more than 9 mm.
  • the manner of planting or arranging the felting needles onto the needle board is important.
  • FIG. 32 the arrangement of the needles 92 of the prior art is such that the needles are planted on the needle board 93 of the conventional fiber needling loom.
  • the crank portions 91 of the needles are observed from the needle ends.
  • FIGS. 33 and 34 show the arrangement of the crank portion of the needle board 94 in the needle loom of the present invention.
  • FIG. 33 an embodiment having three needles is shown.
  • FIG. 34 an embodiment in which seven needles are planted in a common shank is shown.
  • FIG. 35 is a diagram showing the relation between the needle hole 84 viewed across the line XXXVXXV of FIG. 31 and the needle 87, i.e., the manner in which the needles are planted on the needle board.
  • FIG. 35A shows the arrangement of three needles
  • FIG. 358 shows an arrangement of seven needles in a common shank.
  • FIGS. 35C, 35D, 35E and 35F are also preferred embodiments of the present invention.
  • FIG. 35A three needles 87, 88 and 89 are planted at the maximum density.
  • FIGS. 35B through 35F show similar embodiments, but the embodiments of FIGS. 35A and 35B are the most preferable because the needles are excellently fixed.
  • the hole 84 of the needle board is not required to be circular by any means, but it can have rectangular, slitlike, oval, or petal form.
  • the blind needle plays an important role, and in particular, it has an important relation to the crank.
  • FIGS. 36A and B show different arrangements of three needles in which the relation between the crank portions of the needles and the direction of the barbs is shown as is observed from the needle ends.
  • the reference numerial 95 in the diagrams FIGS. 36A and B shows the crank, and the dotted circle 84 shows the hole in the needle board.
  • the circle 97 shows the shank and 98 shows the blade.
  • FIGS. 36A and B show embodiments in which three needles are planted but the directions of the cranks are This can be determined by the direction in which the barbs are placed.
  • FIG. 37A' Almost all of the felting needles which are commercially distributed on the market are those of the standard type as is shown in FIG. 37A' in which the directions of the respective tops of the triangular crosssection of the blade which is called the standard type as is shown in FIG. 37A.
  • the embodiment of FIG. 37B has no such a relation.
  • FIG. 37C is a diagram showing side view of FIG. 37B.
  • the directions of the respective corners of the triangular cross-section of the blade are 60, 300 and 180, and generally they are called the first row, the second row and the third row.
  • the needle composed of the crank portion as is shown in FIG. 37B, and the blade portion is important.
  • the barb when the direction of the barb is turned in the same direction as the crank, i.e., at 0, the barb can be turned outside in all the cases as is shown in FIGS. 33, 34 and 35.
  • the needle of the type of FIG. 37B is the most appropriate felting needle for carrying out the method of the present invention, and in addition, it is quite a new needle which cannot be compared with conventional needles.
  • the felting needle of low throat depth which has a low fiber hooking coefficient is very effective in view of the fact that the needled felt produced has uniformity of fiber needling; the reason for this is that the fibers are not hooked in the form of large bundles.
  • the distance between barbs of the needle be as large as possible, as in the present invention.
  • FIG. 38 is a side view of a blind needle 99 which is useful in the present invention.
  • a blind needle as the term is used in connection with this invention, is a conventional felting needle having no blade portion and no intermdiate blade portion. In other words, in the conventional felting needle as is shown in FIG. 2, the intermediate blade 11 and the blade 12 are not provided in a blind needle.
  • FIG. 38A shows a blind needle produced from a conventional needle
  • FIG. 388 shows a pin type blind needle, or T type blind needle
  • FIG. 38C shows a pin type blind needle whose shank 99 is unusually thick.
  • the characteristic of the blind needle of FIG. 38A is that a defective needle whose blade portion is broken can be effectively used.
  • the blind needle of FIG. 38B is effective as a center needle as in the case of FIG. 358.
  • the blind needle has no blade portion with barb, and therefore it does not take part in the punching directly.
  • the fixation of needles can be made stable by placing a blind needle in the center thereof, and at the same time as the secondary effect, the blind needle can perform the role of preventing the formation of fiber flux needled in the form of a bundle, when needle punching is carried out.
  • the felting needle should be provided perpendicularly and uniformly in relation to the direction in which felt proceeds.
  • the felting needle in a slit form, one-row arrangement, or a rectangular arrangement perpendicularly against the direction in which felt proceeds, rather than a circular arrangement.
  • the needles can be arranged in the lateral direction as uniformly as possible by utilizing the blind needle as effectively as possible even in the case of a circular needle hole.
  • fibers to be used in practicing the present invention conventional ordinary or highly shrinkable polyesters, polyamides, polypropylenes and such synthetic fibers, or natural fibers such as cotton, wool or rayon, can be used in the present invention.
  • the aforementioned islands-in-asea type filament is preferably used in practicing this invention.
  • the fibers mentioned above are formed into a fiber web by means of a typical carding machine or crosslapper and the fiber web is subjected to the needle punching operation by using a needle punching machine of the present invention.
  • the felt takes on a non-uniform structure, but when the punch number is increased, the felt structure becomes uniform.
  • the needle density is 1,500/cm or above, or more preferably above 3,000/cm
  • needle punching should be carried out with a large number of needles after having carried out needle punching with a lesser number of needles, and a uniformly needled structure can be thus obtained.
  • needle punching may be carried out with a conjugated felting needle having a lesser number of needles after having carried out needle punching with a conjugated felting needle having a large number of needles.
  • needle punching after needle punching has been carried out with the conjugated felting needle, subsequently needle punching may be also carried out with a needle having 1 9 barbs, preferably 1 3 barbs.
  • the surface of a needled fabric obtained by using a needle punching loom of the present invention is excellently uniform, and therefore it is preferable in providing slices for subsequent fabrication.
  • EXAMPLE 1 A crimp of 15 to 10 crimps per inch was applied to an islands-in-a-sea type filament of 4.5 denier wherein the island portion thereof was composed of polyethylene terephthalate (the number of islands was 16), and the sea portion thereof was composed of polystyrene (prepared by adding polyethylene glycol), and the ratio of the sea portion to island portion was 50:50, and the filament was cut into 49 mm staple.
  • the staple thus obtained was subjected to opening, and the opened staple was pressed to a carding machine, and then made into web of sheet-like formation by using a cross lapper.
  • the sheet form web thus obtained was subjected to a needle punching machine, and then finished into a needled felt or mat.
  • the needle which as used in this example was provided with one barb, and the barb of the needle having a blade whose cross-sectional height (altitude) was from 0.4826 1 0.0254 mm, was processed with a deadsmooth cut file so that the needle had the ability to hook one fiber on the average, and the needled felt obtained had a structure composed of one needled fiber or fiber flux on the average.
  • the confirmation of the fiber hooking coefficient of the needle was carried out by pressing the web with a coarse metal net, and the needle was injected deeply twenty times into the different net-eyes in the punching state.
  • A The needle having 9 barbs, and the cross-sectional height or altitude of the triangle was the same as in this example: the needle had the ability to hook more than 15 fibers per single injection (the needle corresponds to the commercially distributed No. 40 needle).
  • the fiber web was punched sufficiently to make the apparent density of the felt above 0.15 g/cm; the product of the present invention required at least 5,000 needle punches per square centimeter (punching number).
  • the product of the present invention required at least 5,000 needle punches per square centimeter (punching number).
  • a punching number of at least O/cm was required, and in the case of felt B, at least 1200/cm of punching number, was required.

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  • Engineering & Computer Science (AREA)
  • Textile Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Nonwoven Fabrics (AREA)
US00116146A 1970-02-20 1971-02-17 Needle felting apparatus Expired - Lifetime US3774273A (en)

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JP1444270A JPS4935100B1 (enrdf_load_stackoverflow) 1970-02-20 1970-02-20
JP45014443A JPS4816151B1 (enrdf_load_stackoverflow) 1970-02-20 1970-02-20
JP45061372A JPS4948578B1 (enrdf_load_stackoverflow) 1970-07-15 1970-07-15

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CA (1) CA953089A (enrdf_load_stackoverflow)
CH (1) CH564115A5 (enrdf_load_stackoverflow)
DE (1) DE2108115C3 (enrdf_load_stackoverflow)
FR (1) FR2080671B1 (enrdf_load_stackoverflow)
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US3925866A (en) * 1973-02-21 1975-12-16 Cikalon Vlies Method and needle machine for the production of pile fabrics
US20100251526A1 (en) * 2009-02-12 2010-10-07 Groz-Beckert Kg Needle for a textile machine
US20110041303A1 (en) * 2009-02-12 2011-02-24 Groz-Beckert Kg Needle holder for a textile machine
US20140260438A1 (en) * 2011-11-07 2014-09-18 Midori Hokuyo Co., Ltd. Leather-punching device, leather-punching method and leather sheet
US10321738B2 (en) 2016-01-19 2019-06-18 Nike, Inc. Footwear with embroidery transition between materials
US10448706B2 (en) 2016-10-18 2019-10-22 Nike, Inc. Systems and methods for manufacturing footwear with felting
US10920351B2 (en) 2019-03-29 2021-02-16 Xerox Corporation Sewing method and apparatus to increase 3D object strength
US11046002B2 (en) 2019-03-29 2021-06-29 Xerox Corporation Wetting agent additive for an in-line quality check of composite-based additive manufacturing (CBAM) substrates
US11083246B2 (en) 2016-01-19 2021-08-10 Nike, Inc. Footwear with embroidery transition between materials
US11104077B2 (en) 2019-03-29 2021-08-31 Xerox Corporation Composite-based additive manufacturing (CBAM) image quality (IQ) verification and rejection handling
US11117325B2 (en) 2019-03-29 2021-09-14 Xerox Corporation Composite-based additive manufacturing (CBAM) augmented reality assisted sand blasting
US11130291B2 (en) 2019-03-29 2021-09-28 Xerox Corporation Composite-based additive manufacturing (CBAM) use of gravity for excess polymer removal
US11214000B2 (en) 2019-04-03 2022-01-04 Xerox Corporation Apparatus and method for fabricating multi-sided printed composite sheet structures
US11312049B2 (en) 2019-04-03 2022-04-26 Xerox Corporation Additive manufacturing system for halftone colored 3D objects
US11311079B2 (en) 2016-01-19 2022-04-26 Nike, Inc. Footwear with felting transition between materials
US11318671B2 (en) 2019-05-21 2022-05-03 Xerox Corporation System and method for sheeting and stacking 3D composite printed sheets
US11485110B2 (en) 2019-03-29 2022-11-01 Xerox Corporation Cross layer fiber entanglement to increase strength of 3D part
US11518092B2 (en) 2019-06-19 2022-12-06 Xerox Corporation Patterned pre-stop for finishing additive manufactured 3D objects
US11731352B2 (en) 2019-03-29 2023-08-22 Xerox Corporation Apparatus and method for fabricating multi-polymer composite structures

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FR2548231B1 (fr) * 1983-10-25 1985-10-31 Buteux Patrick Procede d'implantation de cheveux sur un support en feuille
US5077874A (en) * 1990-01-10 1992-01-07 Gates Formed-Fibre Products, Inc. Method of producing a nonwoven dibrous textured panel and panel produced thereby
US5199141A (en) * 1990-01-10 1993-04-06 Gates Formed-Fibre Products, Inc. Method of producing a nonwoven fibrous textured panel and panel produced thereby
DE4114873A1 (de) * 1990-05-16 1991-11-21 Fehrer Ernst Vorrichtung zum nadeln eines vlieses
AT398212B (de) * 1990-05-16 1994-10-25 Fehrer Ernst Vorrichtung zum nadeln eines vlieses
DE502009000460D1 (de) 2009-02-12 2011-04-28 Groz Beckert Kg Nadel für eine Textilmaschine
US9856592B2 (en) * 2016-03-15 2018-01-02 Goodrich Corporation Methods and systems for forming a fibrous preform

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Cited By (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3925866A (en) * 1973-02-21 1975-12-16 Cikalon Vlies Method and needle machine for the production of pile fabrics
US20100251526A1 (en) * 2009-02-12 2010-10-07 Groz-Beckert Kg Needle for a textile machine
US20110041303A1 (en) * 2009-02-12 2011-02-24 Groz-Beckert Kg Needle holder for a textile machine
US8245373B2 (en) 2009-02-12 2012-08-21 Groz-Beckert Kg Needle holder for a textile machine
US8458870B2 (en) 2009-02-12 2013-06-11 Groz-Beckert Kg Needle for a textile machine
US20140260438A1 (en) * 2011-11-07 2014-09-18 Midori Hokuyo Co., Ltd. Leather-punching device, leather-punching method and leather sheet
US10321738B2 (en) 2016-01-19 2019-06-18 Nike, Inc. Footwear with embroidery transition between materials
US11864627B2 (en) 2016-01-19 2024-01-09 Nike, Inc. Footwear with embroidery transition between materials
US11083246B2 (en) 2016-01-19 2021-08-10 Nike, Inc. Footwear with embroidery transition between materials
US11311079B2 (en) 2016-01-19 2022-04-26 Nike, Inc. Footwear with felting transition between materials
US10448706B2 (en) 2016-10-18 2019-10-22 Nike, Inc. Systems and methods for manufacturing footwear with felting
US12161192B2 (en) 2016-10-18 2024-12-10 Nike, Inc. Systems and methods for manufacturing footwear with felting
US11117325B2 (en) 2019-03-29 2021-09-14 Xerox Corporation Composite-based additive manufacturing (CBAM) augmented reality assisted sand blasting
US11130291B2 (en) 2019-03-29 2021-09-28 Xerox Corporation Composite-based additive manufacturing (CBAM) use of gravity for excess polymer removal
US11104077B2 (en) 2019-03-29 2021-08-31 Xerox Corporation Composite-based additive manufacturing (CBAM) image quality (IQ) verification and rejection handling
US11485110B2 (en) 2019-03-29 2022-11-01 Xerox Corporation Cross layer fiber entanglement to increase strength of 3D part
US11731352B2 (en) 2019-03-29 2023-08-22 Xerox Corporation Apparatus and method for fabricating multi-polymer composite structures
US11840784B2 (en) 2019-03-29 2023-12-12 Xerox Corporation Sewing method and apparatus to increase 3D object strength
US11046002B2 (en) 2019-03-29 2021-06-29 Xerox Corporation Wetting agent additive for an in-line quality check of composite-based additive manufacturing (CBAM) substrates
US10920351B2 (en) 2019-03-29 2021-02-16 Xerox Corporation Sewing method and apparatus to increase 3D object strength
US11214000B2 (en) 2019-04-03 2022-01-04 Xerox Corporation Apparatus and method for fabricating multi-sided printed composite sheet structures
US11312049B2 (en) 2019-04-03 2022-04-26 Xerox Corporation Additive manufacturing system for halftone colored 3D objects
US11318671B2 (en) 2019-05-21 2022-05-03 Xerox Corporation System and method for sheeting and stacking 3D composite printed sheets
US11518092B2 (en) 2019-06-19 2022-12-06 Xerox Corporation Patterned pre-stop for finishing additive manufactured 3D objects

Also Published As

Publication number Publication date
GB1327993A (en) 1973-08-22
FR2080671B1 (enrdf_load_stackoverflow) 1973-11-23
CA953089A (en) 1974-08-20
DE2108115C3 (de) 1978-04-20
FR2080671A1 (enrdf_load_stackoverflow) 1971-11-19
DE2108115A1 (de) 1971-09-23
DE2108115B2 (de) 1977-09-01
CH564115A5 (enrdf_load_stackoverflow) 1975-07-15

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