NEEDLE FOR USE IN TUFTING MACHINE

Abstract: A needle for a tufting machine having its bottom end pointed and having its lower half portion flattened. The flattened portion has one edge thereof chamferred to form a tapered face (3). A yarn insert hole (4) is formed above the pointed tip (1). It is inclined at a predetermined angle (α) so that its lowermost point will be located nearer to the tapered edge (3) than the other edge. The inclined hole (4) allows the looper to hook the yarn more reliably and helps to decrease the possibility of cutting or mishooking of the yarn.

Description: The present invention relates to a needle for use in a tufting machine for manufacturing a tufted carpet. As shown in Fig. 8, a tufting machine has a vertically movable needle 42 for planting a pile yarn 43 through a web of base cloth 41 being fed horizontally through the machine and a looper 44 for hooking at its tapered tip the pile yarn 43 planted to form loops 45 on the underside of the base cloth 41. As shown in Fig. 9 (see also the document EP-A-163 278), a prior art needle for a tufting machine has its bottom end pointed as at 46 and has a thin-walled flat middle portion having one edge thereof chamfered into a tapered face 47 to allow easy insertion of the horizontally movable looper 44 between the yarn and the needle 42. An oval yarn insert hole 48 is formed slightly above the pointed tip 46 so that its major axis will coincide with the axis 49 of the needle 42. The looper 44 serves to catch the yarn planted through the base cloth 41 to form loops. In order to produce a patterned carpet by use of pile yarns X, Y and Z different colors as shown in Fig. 10, it is necessary to swing the needles of a tufting machine laterally (in the direction of arrows A in Fig. 10). But, if such a prior art needle is swung laterally e.g. by five stitches at one stroke to form a large pattern on a carpet, the pile yarn put through the needle 42 will be pulled laterally, too, as shown in Figs. 11 and 12, and be slanted extremely at a portion between the top end of the yarn insert hole 48 and the side of the looper 44 so that the length a of the yarn at this portion will be too short for the looper to hook the yarn reliably. This will increase the possibility of cutting or mishooking of the yarn, thus making it necessary to repair the pattern afterwards. It was therefore difficult to form a large and beautiful pattern on a carpet with such prior art needles. It is an object of the present invention to provide a needle for a tufting machine which obviates the abovesaid shortcomings and which can be moved sideways up to about a five-stitch length at a stroke without the fear of cutting or mishooking of the yarn. In accordance with the present invention there is provided a needle for a tufting machine having its bottom end pointed and having the lower half portion thereof flattened, the flattened portion having an edge at one side thereof chamfered to form a tapered edge, the needle being formed with a yarn insert hole above the pointed tip, characterised in that the yarn insert hole is inclined at a predetermined angle so that its lowermost point will be located nearer to the tapered edge than the other edge. Other features and objects of the present invention will become apparent from the following description taken with reference to the accompanying drawings, in which: Figs. 1 to 3 are plan views of a portion of the needles embodying the present invention; Fig. 4 is a sectional view of the needle of Fig. 2; Fig. 5 is a plan view of the same showing how it is used; Fig. 6 is a similar view of the same with the needle at a higher position; Fig. 7 is a side view of the same; Fig. 8 is a view showing how a needle of a tufting machine operates; Fig. 9 is a plan view of a prior art needle; Fig. 10 is a bottom plan view of a carpet having a pattern formed with the prior art needle; Fig. 11 is a plan view of the prior art needle of Fig. 9 showing how it is used; and Fig. 12 is a side view of the same. Now referring to Figs. 1 to 6, the needle for a tufting machine according to the present invention has its intermediate portion cut out at one side as shown at 2 to form a thin-walled flat portion. An edge at one side of the cut surface 2 is chamfered to form a tapered surface 3. The needle has a smoothly finished surface as a whole. A yarn insert hole 4 is formed in the needle between its tip 1 and the bottom end of the cut surface 2 so as to extend obliquely at an angle α of 50 to 60 degrees (Fig. 1). Its lowermost point is located nearer to the tapered edge 3 than the other edge. The shape of the hole 4 may be parallelogrammatic (as in Fig. 1), rectangular (as in Fig. 2), or oval (as in Fig. 3). The yarn insert hole 4 of the embodiment of Fig. 1 is in the shape of a parallelogram having its four corners rounded off and its short sides extending in parallel with the axis 6 of the needle. Its peripheral surface is finished up smoothly. Now the operation of the needle for a tufting machine according to the present invention will be described. If the yarn 43 pulled by the needle is planted into the base cloth after moving the needle sideways by about five stitches at a stroke, it will engage the needle at the uppermost point in the hole 4, i.e. the point farthest from the axis 6 of the needle. In other words, the yarn 43 will be inclined toward the edge 3, starting from a point apart from the axis 6 of the needle by a distance b and thus, as shown in Fig. 5, the length c of the portion of the yarn 43 in engagement with the side surface of the needle will be longer than that on the prior art needle shown in Fig. 11. This allows the looper to hook the yarn at its tip more reliably. The needle according to the present invention, which can be moved by a longer distance sideways than any other prior art needle without the fear of the cutting or mis-hooking of the yarn, will make it possible to form a large and luxurious-looking pattern on a carpet with a greater number of yarns of different colors. Also, less possibility of cutting or mishooking increases the productivity and quality and less repair decreases the manufacturing cost.

Claims: A needle for a tufting machine having its bottom end pointed and having the lower half portion thereof flattened, said flattened portion having an edge at one side thereof chamfered to form a tapered edge (3), said needle being formed with a yarn insert hole (4) above said pointed tip (1), characterised in that said yarn insert hole (4) is inclined at a predetermined angle (α) so that its lowermost point will be located nearer to said tapered edge (3) than the other edge.

Inventors: TAMOTSU, HAKUI
Applicants: ASAHI TRADING CO., LTD., HAKUI, SHINGO
Application year: 1989
Main classification: D05C15
IPC codes: D05C15