Three-dimensional Fabric, And Method And Loom Construction For The Production Thereof

Abstract

Method of weaving a three-dimensional fabric which comprises the steps of inserting a number of doubled weft yarns between the layers of the warp yarns, securing the loops which connect the weft yarns by means of a binder yarn threaded therethrough, inserting vertical yarns between the vertical rows of warp yarns perpendicularly to the weft and warp yarns, and after repeating the first two steps beating the woven yarn with a reed. A loom for carrying out this process is also disclosed.

Description

FIELD OF THE INVENTION

This invention relates to a three dimensional fabric woven of warp, weft and vertical yarns and to a method and a loom for the production thereof.

Three-dimensional fabrics have extensive usage, for example, as brake linings, as fillers for valves and as reinforcing material.

Existing three-dimensional fabrics are mostly formed by superposing or laminating multiple layers of plane or flat fabrics with use of a suitable adhesive agent, or by connecting more than two layers of plane fabrics to an intermediate fabric layer. These fabrics can be said to have a three-dimensional shape but do not have a three-dimensional construction in a strict sense because of the use of merely two types of yarns, i.e., warp and weft yarns. With the so-called woven belt in which the thickness in the vertical direction of the belt is imparted by interweaving weft yarns with a portion of warp yarns, the thickness of the fabric is limited and it is difficult to obtain a three-dimensional fabric construction of a desired thickness. More recently, there has been introduced a three-dimensional fabric of a small block form having a side of several centimeters in section, which is formed by interweaving glass fibres in three different directions which are perpendicular to each other. However, such woven belt does not suit for production on an industrial scale since it requires a great amount of manual labor and efforts for interconnecting individual yarns portion by portion and naturally has limitations in the size of the fabric to be woven.

OBJECT OF THE INVENTION

The present invention has as its object the provision of a three-dimensional fabric construction and a weaving method and apparatus for the production thereof, which allow formation of the three-dimensional fabric on an industrial scale, in a desired size and in the same simple manner as in weaving of flat fabrics, the three-dimensional fabric being imparted with sufficient mechanical strengths in all directions by means of groups of warp, weft and vertical yarns which are interwoven perpendicularly to each other.

When weaving a three-dimensional fabric of desired length, width and thickness by interweaving warp, weft and vertical yarns perpendicularly to each other, a first question that occurs first is by what method and apparatus an intended fabric construction is obtained in a simple manner. This question also relates to determination of the particular weave construction to be employed in the three-dimensional fabric intended.

SUMMARY OF THE INVENTION

In the present invention, a three-dimensional fabric is formed efficiently by a simple method and apparatus which are comperable to those of flat fabrics, the three-dimensional fabric being formed by repeating a cycle of operation which comprises the steps of inserting doubled weft yarns which are looped at fore ends thereof into spaces between warp yarns which are parallelly aligned in vertical and horizontal directions to provide a number of warp layers and rows, securing the weft yarns by inserting a selvage binder yarn into the weft loops, and introducing vertical yarns into spaces between vertical rows of the warp yarns.

In the loom construction according to the present invention, the fore feeding ends of a vertical yarn inserting device are curved in one and same direction for feeding the vertical yarns with a space behind lastly inserted vertical yarns to allow insertion of a weft inserting device therethrough. The weft inserting device is provided at the fore end thereof with a weft guide hole for receiving a weft yarn and with a recessed portion within a loop formed by the weft yarn for passing a binder threading needle, thus simplifying the loom construction and carrying out the weaving operation in a secure manner.

According to the method and loom construction of the present invention there is provided a three-dimensional fabric construction which comprises: a plurality of warp yarns parallelly aligned in horizontal and vertical directions to form a number of horizontal warp layers and vertical warp rows; a number of weft yarns inserted into spaces between the respective warp layers of said warp yarns in a direction perpendicular thereto and being turned at one side of said fabric around a vertical yarn and at the other side around a binder yarn which is inserted into loops formed by said weft yarns at said other side of said fabric for holding said weft yarns securely in position; and a number of vertical yarns inserted into spaces between the respective vertical warp rows of said warp yarns in a direction perpendicular to both of said warp yarns and said weft yarns and turned around outermost weft yarns at both sides of said fabric.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other object, features and advantages of the present invention will become apparent from the following description and appended claims, and from the accompanying drawings, wherein like parts are designated by like reference numerals and characters, and in which:

FIG. 1 is a perspective view explanatory of the weaving steps of the method according to the invention and the fabric construction formed thereby;

FIg. 2 is a perspective view showing by way of example a weft inserting device according to the present invention;

FIGS. 3(A) to FIG. 3(D) are diagrams showing the steps of the weft inserting operation by the device shown in FIG. 2;

FIG. 4 is a perspective view showing a modified structure of the weft inserting device according to the present invention;

FIG. 5 is a perspective view diagrammatically showing binder threading and connecting operations;

FIG. 6 is a perspective view showing details of an upper vertical yarn inserting device employed in the loom according to the present invention;

FIG. 7 is a side view showing interweaving operation of the weft and vertical yarns;

FIG. 8 is a diagram showing in plan view the yarn arrangment in the three-dimensional fabric construction formed by the method according to the present invention;

FIG. 9 is a diagram showing the same fabric construction in side view;

FIG. 10 is a perspective view showing a loom embodying the present invention; and

FIG. 11 is a diagram showing a weaving program for forming the three-dimensional fabric according to the present invention.

DESCRIPTION OF PREFERRED EMBODIMENT

A preferred embodiment of the present invention will now be described particularly and in detail with reference to the accompanying drawings.

Referring to FIG. 1 which diagrammatically shows weaving operation according to the present invention, wherein the warp yarns Y,Y,Y, . . . , Y are passed through a reed 1 through a number of holes formed therein at uniform intervals in both horizontal and vertical directions, the warp yarns being supported and tensioned suitably by a pair of supporting members 2 and 3 which are located at both ends of the loom as will be described in more greater detail with reference to FIG. 10. The warp yarns Y are arranged in multiple layers each of which has a number of yarns which run in one horizontal plane in parallel relation with or at an equal space from adjacent yarns. The warp yarns of the respective layers are in vertical alignment, forming regularly spaced vertical warp rows.

In order to pick in weft yarns X,X,X . . . , X and vertical yarns Z,Z . . . ,Z into the horizontally and vertically aligned warp yarns, the weft inserting device 6 is first picked transversely or perpendicularly to the warp yarns while maintaining the upper and lower vertical yarn inserting devices 4 and 5 in the upper and lower retracted positions as shown in FIG. 1, each of the weft yarns X,X, . . . X being inserted between the warp layers in double fold forming a loop at the fore end thereof. The weft inserting device 6 is temporarily stopped when the looped fore ends of the weft yarns are projected out of the warp yarns on the opposite side for threading a binder yarn P.

FIG. 2 diagrammatically shows the construction of the weft inserting device by way of example, wherein the weft inserting device 6 comprises a number of elongated picking plates 7,7, . . . ,7 which are spaced from each other at the same distance as the warp layers and are securely supported on a supporting member 8 for insertion into the spaces between the respective layers of the tensioned warp yarns. Each one of the picking plate 7 has the tip end thereof bifurcated by a forwardly opened U-shaped notch or cut-away portion 9. One of the bifurcated end portions of the picker plate 7 is transversely formed with a weft guide through hole 10 which extends from the outer side of the plate to the notched or recessed inner side while the other bifurcated end portion of the picking plate has formed on the tip end face thereof with a weft guide groove 11 for engagement with a weft yarn.

The operation performed by the weft inserting device 6 mentioned above will now be described with reference to FIGS. 3A to 3D. After positioning of the vertical yarns Z,Z, . . . ,Z, the picking plates 7 of the weft inserting device 6 are passed into the respective spaces between the warp yarn layers as shown in FIG. 3A. In this instance, the weft inserting device 6 catches and holds the weft yarns in the weft guide grooves 11 in the vicinity of the first row of the warp yarns, and advances transversely of the warp rows as shown in FIG. 3B for filling in the weft yarns. When the fore ends of the picking plates 7 of the weft inserting device 6 are projected outwardly on the other side of the warp yarns, the weft inserting device 6 is temporarily stopped for threading a binder yarn into the looped ends of the weft yarns by means of a selvage binder inserting needle 12 which will be described hereinlater. This binder threading operation is shown particularly at (C) of FIG. 3. After insertion of the selvage binder yarn, the weft yarns X are disengaged from the weft guide grooves 11 as the weft inserting device 6 is retracted to the initial position, guiding the weft yarns X under tensioned conditions by means of the weft guide holes 10 as shown at (D) of FIG. 3.

FIG. 4 shows a modified structure of the weft inserting device. In this modification, the weft picker is provided with a number of picking plates 7a which are similar to those of the embodiment described above but each has at the fore end thereof a sidewardly opened U-shaped recess 9a and a weft guide hole 10a which extends transversely through the picking plate 7a at the tip end thereof. When this modified weft inserting plate 7a is employed, in order to prevent the binder inserting needle 12 and the binder yarn from hitting on the edges of the recessed portion 9a, it is preferred to take measures for displacing the whole picking plate or the fore end portion thereof in a suitable direction or measures for displacing the selvage binder insertion needle 12 when it is disengaged from the recessed portion 9a.

The selvage formation is carried out by passing from above a binder inserting needle 12 which holds a binder yarn P in its needle hole 13 through vertically aligned weft loops as shown in FIG. 5. When the binder inserting needle 12 is passed through the weft loops, a selvage securing latch needle 14 is advanced toward the binder insertion needle 12 to catch the binder yarn P, the latch needle 14 returning to the initial position after catching the binder yarn P. In this instance, the latch 15 of the latch needle 14 is adapted to be closed as it hits on a guide member which is provided in the path of movement of the latch needle 14 and the binder yarn P caught by the latch needle 14 is passed through a binder loop formed in the previous cycle of operation. After the binder yarn P is caught by the latch needle 14, the binder insertion needle 12 is returned to its initial upper position.

The weaving of the binder P at the selvage may be carried out by simply moving the binder inserting needle 12 up and down through the weft loops without using the latch needle as mentioned hereinabove.

During or after the binder weaving operation, the weft inserting device 6 retracts to its initial position and the reed 1 beats up the weft yarns which have been picked in between the respective warp layers.

Upon completion of one cycle of weft inserting operation, the upper and lower vertical yarn inserting devices 4 and 5 are simultaneously lowered and raised, respectively, for introducing the upper and lower vertical yarns Z,Z, . . . ,Z and Z',Z', . . . ,Z', into the spaces between the vertical rows of the warp yarns.

FIG. 6 diagramatically shows details of the construction of the upper vertical yarn inserting device 4, which comprises a plurality of vertical yarn picking pipes 16 of metallic material with the lower ends thereof curved in the same direction, each vertical yarn picker pipe being secured on a supporting member 17 parallel to and at a such distance from adjacent pipes that one picking pipe is inserted into every two spaces between the vertical rows of the warp yarns. This vertical picking means is not necessarily required to be formed from a pipe and instead a flat plate with a guide means for the vertical yarn may be used.

The lower vertical yarn inserting device 5 may have the same construction as the upper vertical picking means 4 with the vertical yarn picking pipes 16 in an inversed position for introducing from beneath the lower vertical yarns into he spaces between the vertical rows of the warp yarns, in such a manner the spaces between the vertical warp rows receive alternately the upper and lower vertical yarn picking pipes.

The upper vertical yarns Z,Z, . . . ,Z which are fed from bobbins are guided into the respective picking pipes 16 from the upper ends thereof and are taken out through the curved lower ends. The lower vertical yarns Z',Z', . . . ,Z' are fed in he same manner except that they are guided into he lower picking pipes from the lower ends and taken out through the upper curved ends thereof.

The upper and lower vertical yarn picking devices 4 and 5 start movement into the warp yarns from the respective positions shown in FIG. 1 when one cycle of weft picking operation has been completed. The picking pipes 16 and 18 of the upper and lower vertical yarn picking devices 4 and 5 are inserted alternately into the spaces between the vertical rows of warp yarns, as shown in FIG. 7, until the curved fore ends of the pipes 16 and 18 projected outwardly from the opposite upper and lower side of the aligned warp yarns, respectively. The upper and lower vertical yarns Z,Z' are turned around the lowermost and uppermost weft yarn layers perpendicularly thereto in the spaces between the vertical rows of the warp yarns Y,Y, . . . ,Y.

The weft yarns X,X, . . . ,X are then inserted again in the same manner as described hereinbefore. In this instance, the picker plates 7 of the weft yarn inserting device 6 should be introduced into the spaces between the warp layers without hitting on the vertical yarn picking pipes 16 and 18. For this purpose, the fore end portions of the vertical yarn picking pipes 16 and 18 are curved to provide a space beneath and over the upper and lower vertical yarn picking pipes 16 and 18 to allow insertion of the weft inserting device 6 therethrough, the width of the space being slightly larger than the width of the weft picking plates 7.

Referring to FIG. 7, when the weft yarns are picked in by the weft inserting device 6 and the binder yarn P has been passed through the loops formed at the fore ends of the respective doubled weft yarns, the weft inserting device 6 is retracted to complete one cycle of weft picking operation. After the retract of the weft inserting device 6, the upper and lower vertical yarn inserting devices 4 and 5 are retracted to the respective upper and lower positions, thus filling in the upper and lower vertical yarns Z and Z'. A three-dimensional fabric may be woven by repeating the various operations described above.

FIG. 8 diagramatically shows in a plan view the weave construction of the three-dimensional fabric formed in the manner as described hereinbefore, while FIG. 9 shows the same weave construction in a side elevation. It will be seen from these figures that, in the fabric construction according to the present invention, the weft yarns are interwoven with and extended over the entire width of the warp yarns which are tensioned parallelly in horizontal and vertical rows, the weft yarns being secured by a binder yarn P at one side of the fabric and by the outermost warp yarn at the other side. On the other hand, the upper and lower vertical yarns Z and Z' are turned around at the top and bottom of the fabric in such a manner as to connect adjacent two weft yarns together in a position between the vertical rows of the warp yarns.

Examples of materials which are useful for weaving the three-dimensional fabric according to the present invention are ordinary organic fibrous materials such as cotton, linen, wool, nylon, polyester and polypropyrene and the like and other inorganic fibrous materials such as glass fibre, carbon fibre, metallic fibre, asbestos and the like. It will be appreciated that the fibrous materials just mentioned may be used in a spinned form or in the form of a filament.

FIG. 10 shows a loom which is adapted to produce a three-dimensional fabric in accordance with the weaving method discussed hereinbefore. The apparatus shown in FIG. 10 has the weft picking or inserting device 6 on an opposite side of the warp yarn rows as compared to the embodiment shown hereinbefore. It will understood that this makes no material difference.

Referring to FIG. 10, the loom is supported on a machine frame 19 which has mounted at the fore and rear ends thereof a pair of supporting plates 2 and 3. The supporting plate 2 has a plurality of fine holes at such positions suitable for holding the fore ends of the horizontally and vertically aligned warp yarns. The fore ends of the warp yarns which are passed through these fine holes are secured in position by suitable means provided on the opposite or rear side of the warp supporting plate 2. The other supporting plate 3 is also provided with a number of fine holes in a similar manner. The other or rear ends of the warp yarns are passed through these fine holes of the warp supporting plate 3 and have weights suspended therefrom for imparting suitable tension to the aligned warp yarns.

The reed member 1 passing the warp rows, upper vertical yarn inserting means 4, lower vertical yarn inserting means 5, weft inserting means, binder threading needle 12 and mechanisms for operating these component parts are all supported on a carrier 21 which is mounted on and movable back and forth along guide rods 22 which are fixed on the machine frame 19 on each side thereof. As the weaving of the fabric proceeds by repeating the cycle of operation which consists of insertion of weft yarns, insertion of vertical yarns, threading of the binder yarn, the carrier 21 is moved toward the unwoven ends of the warp yarns by a necessary distance by rotating a rod screw 24 by a motor.

The upper vertical yarn inserting device 4 mounted on the carrier 21 has a construction as described hereinbefore with reference to FIG. 6 and has vertical inserting yarns Z,Z, . . . ,Z fed from bobbins 25. The upper vertical yarn inserting device 4 has a moving member connected to the supporting member 8 thereof, the moving member 26 is movable up and down under a guidance of a suitable guide means which is not shown in the drawings. The upward and downward movements of the moving plate member 26 are imparted by rotation of a rod screw 27 which is threaded therethrough. The rod screw 27 is connected, through an electromagnetic breakes 28, 28 and electromagnetic clutches 29, 29 to a pair of motors 30, 30 which are adapted to rotate in opposite directions. With the two motors 30, 30, the direction of rotation of the rod screw 27 may be changed promptly by sending operation signals to the electromagnetic breakes 28, 28 and electromagnetic clutches 29, 29 in accordance with weaving cycles of the vertical yarns for imparting the required upward and downward movements to the upper vertical yarn inserting device 4, without changing the directions of rotation of the respective motors 30, 30.

The lower vertical inserting yarns Z',Z', . . . ,Z' fed from bobbins 31 are, as mentioned hereinbefore, introduced into the spaces between the vertical rows of the warp yarns by the lower vertical yarn inserting device 5 which is also movable up and down under guidance of a suitable guide means (not shown) and to which upward and downward movements are imparted by a rod screw 32 in a manner similar to the upper vertical yarn inserting means 4. In this instance, the direction of such movements may suitably be switched by connecting and disconnecting the motors 35, 35 which rotates in opposite directions, through operation of electromagnetic brakes 33, 33 and electromagnetic clutches 34, 34.

The upward and downward movements of the lower vertical yarn inserting device 5 may be synchronized with the movements of the upper vertical yarn inserting means 4. However, the movements of the upper and lower vertical yarn inserting means 4 and 5 may be staggered, if desired.

On the other hand, the weft inserting device 6 which functions to pick the weft yarns into the rows of warp yarns has a construction as described hereinbefore with reference to FIG. 2 and has the weft yarns fed from weft bobbin 36 through a guide member 37. The supporting member 8 of the weft inserting device 6 is mounted such that it is moved toward and away from the warp yarn rows by rotation of a rod screw 38. Horizontal reciprocating movements are imparted to the supporting member of the weft inserting means 6 by a pair of motors which are adapted to rotate in opposite directions, through electromagnetic brakes 40, 40 and electromagnetic clutches 41, 41 in a manner similar to the feed of vertical yarns.

The upward and downward movements of the selvage binder threading needle 12 are imparted by rotation of a motor 43 through a screw 42 for threading the binder yarn through the loops formed at the fore ends of the doubled weft yarns.

The latch needle 14 is deleted from FIG. 10 for simplicity of illustration. However, it should be noted that the latch needle 14 is reciprocated for catching the binder yarn by means of a eccentric cam member 47 which is rotated by a motor 44 through an electromagnetic brake 45 and electromagnetic clutch 46, and a return spring 48.

The reed 1 is moved toward the woven fabric at suitable intervals time for beating the filled-in weft and vertical yarns. In this instance, the reed 1 alone may be moved by a motor and the like or the carrier 21 supporting the reed 1 thereon may be moved by means of the motor 23 for this purpose.

In the embodiment described hereinbefore, the rows of the warp yarns are described as being fixedly supported in a horizontal position while the carrier 21 is moved for forming the three-dimensional fabric. However, it is possible to design and construct the loom such that the horizontal and vertical rows of the warp yarns are fed into the carrier which is held in a stationary position for carrying out the picking operations of the weft and vertical yarns, thus forming a three-dimensional fabric in a continuous manner.

Furthermore, it is also possible to hold the tensioned warp yarns in a vertical position, inserting horizontally the weft and vertical yarns from two different directions which are perpendicular to each other. Such loom requires only a small floor space and thus is particularly advantageous for industrial applications.

FIG. 11 shows an example of operation program of the loom mentioned above, wherein the solid lines extending beneath the step numbers show positions, upper and lower or forward and backward, of the various operating parts or components indicated on the lefthand of the respective lines. In case of the carrier, for example, the line shows the retracting timing in the weaving process.

While specific forms of the present invention have been disclosed in the foregoing description, it will be understood that various modifications within the spirit of the invention may occur to those skilled in the art. Therefore, it is intended that no limitation be placed on the invention except as defined by the scope of the appended claims.

In the FIG. 11, "U.V.Y.I.D" is upper vertical yarn inserting device, "L.V.Y.I.D" is lower vertical yarn inserting device, "W.I.D" is weft inserting device, "B.I.N" is binder inserting needle, "S.S.L.N" is selvage securing latch needle, "RE" is reed and "CA" is carrier.

Claims

What is claimed is:

1. A method for weaving a three-dimensional fabric, characterized in that said method comprises the steps of:

a. inserting a number of doubled weft yarns which are connected by a loop at the respective fore ends thereof into spaces between layers of warp yarns which are in horizontal and vertical alignment and maintained under tensioned conditions,

b. threading a binder yarn through the loops at the fore end of said weft yarns for securing the same in position;

c. inserting vertical yarns into spaces between vertical rows of said warp yarns in a direction perpendicular to both said warp and weft yarns;

d. repeating the steps (a) and (b) after insertion of said vertical yarns; and

e. beating the woven yarns by a reed at a suitable time between the foregoing steps.

2. A loom for weaving a three-dimensional fabric, comprising;

a. a supporting member for supporting warp yarns which are maintained in vertical and horizontal alignment under tensioned conditions;

b. a reed provided at a position where weft and vertical yarns are inserted into said warp yarns for maintaining said warp yarns in vertical and horizontal alignment and movable back and forth in the direction of the warp yarns for beating weft and vertical yarns which have been interwoven;

c. a weft inserting device movable in a direction perpendicular to said warp yarns for inserting weft yarns into spaces between layers of said warp yarns;

d. a binder threading needle for threading a binder yarn into loops at the fore ends of said weft inserting device which are located in the spaces between the respective layers of said warp yarns when said fore ends of said weft inserting device have passed through said warp yarns;

e. a vertical yarn inserting device movable in a direction perpendicular to both said warp and weft yarns and has a first stop position retracted from said warp yarns and a second stop position passed through said warp yarns for allowing insertion of said weft yarns; and

f. means for displacing said reed, weft inserting device, vertical yarn inserting device and binder threading needle relatively with respect to and in the direction along the length of said warp yarns.

3. A loom for weaving a three-dimensional fabric as set forth in claim 2, characterized in that fore end portions of said vertical yarn inserting device from which said vertical yarns are led out are curved in the same direction to provide a space behind lastly inserted vertical yarns to allow insertion of said weft yarn inserting device.

4. A loom for weaving a three-dimensional fabric as set forth in claim 2, characterized in that said weft yarn inserting device is provided at the fore end thereof with a weft guid hole for inserting a weft yarn and with a recessed portion within looped fore end of said weft yarns for passing therethrough said binder yarn threading needle.

5. A loom for weaving a three-dimensional fabric as set forth in claim 2, characterized in that said loom further comprises a latch needle which is movable toward and away from said for catching a binder yarn loop through a loop formed in a previous cycle of operation when said binder threading needle has been passed through said weft loops.

6. A loom for weaving a three-dimensional fabric as set forth in claim 2, characterized in that said supporting member for said warp yarns is securely mounted on a machine frame, and said reed, weft yarn inserting device, vertical yarn inserting device and binder threading needle are mounted on a carrier which is movable along the length of said warp yarns.