Patent Publication Number: US-6209588-B1

Title: Weaving machine with pneumatic weft insertion and catch selvedge forming device

Description:
BACKGROUND AND SUMMARY OF THE INVENTION 
     This application claims the priority of German application 198 02 910.1-26, filed in Germany on Jan. 27, 1998. 
     The invention relates to a weaving machine with a reed having a weft insertion channel, the reed being connected with a reed stay. The reed pivots alternately from a weft insertion position into a weft beating-up position. At least one reed filler is located on the output side of the weft insertion channel in a stationary position in the weft insertion position, the filler having a weft channel. At least one device is provided in the weft beating-up position on the output side of the reed for cutting a weft beaten up on the beating-up edge of a fabric. At least one device is provided for forming a tucked selvedge on the fabric. At least one weft stop motion is located on the output side of the weft insertion channel for detecting the correct insertion of the weft. 
     A weaving machine with at least one reed filler located on the output side of the insertion channel of a reed in a stationary position in the weft insertion position is known from European Patent 0 532 931 (corresponds also to U.S. Pat. No. 5,253,181). 
     To monitor the correct insertion of a weft, in known fashion, a first weft stop motion is provided on the output side of the weft insertion channel that is either integrated in the end area of the reciprocating reed or which is located on the output side of the weft insertion channel at a distance from the reed in an auxiliary reed that is connected with the reed stop. 
     An auxiliary reed of this kind is known from French Patent 2,494,731 (corresponds also to U.S. Pat. No. 4,432,399), which has, in addition to the first weft stop motion in the plane of the weft insertion, a second weft stop motion at a distance therefrom. A reed of this kind with a weft stop motion in the input and output areas of the thread channel is connected with the reed stay at a distance from the reed. 
     The use of an auxiliary reed of this kind is not suitable in conjunction with a device for forming a tucked selvedge, particularly because no means are provided for keeping the inserted weft stretched downstream from the first weft stop motion. 
     A weaving machine for producing single- or multi-web fabric is known from German Patent 44 43 899 (corresponds also to U.S. Pat. No. 5,649,570), which has at least a combination of a cutting device and a tucker mean. 
     In the weft insertion position, at least on the output side of the weft insertion channel of the reed, a reed filler is located in a fixed position. An auxiliary reed for forming a so-called catch selvedge is located downstream from the stationary reed filler. The auxiliary reed performs the same oscillating movements as the reed for inserting the weft and beating it up. At least one weft stop motion is integrated into the auxiliary reed that has a weft channel on the output side of the weft, said stop motion detecting the correct insertion of the weft for the weaving machine control. 
     In view of the fact that the at least one weft stop motion is located in said auxiliary reed on the output side of the weft, the free end of the inserted weft must have a length which is at least great enough for the end to pass the first weft stop motion. 
     This arrangement of said first weft stop motion produces a weft waste of several millimeters. 
     A goal of the invention therefore is to provide measures to prevent the abovementioned weft waste from occurring. 
     According to the invention, this goal is achieved in that at least the first weft stop motion is integrated on the output side of the weft insertion channel with the reed filler which is in a fixed position. 
     The solution according to the invention results in a reduction of the weft waste which corresponds at least to the length of the first weft stop motion integrated into the reed filler. 
     Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a schematic top view of a weaving machine according to the prior art; 
     FIG. 2 is a schematic top view of a weaving machine, with the arrangement of a first weft stop motion according to the invention. 
    
    
     DETAILED DESCRIPTION OF THE DRAWINGS 
     FIG. 1 shows a schematic top view of a weaving machine with a main warp  19 , a reed  2  and a first reed filler  3  with weft channel  3   a . A weft insertion device operates pneumatically and is located upstream from the first reed filler  3 . A fabric support  18  is located in front of the beating-up edge  13   a  of a fabric being woven. Downstream from reed  2  on the output side of the weft insertion channel  2   a  is a second reed filler  6  with reed channel  6   a , as well as an auxiliary reed  7  with a weft channel  7   a  and a weft-stretching and detecting device  10 . 
     When weft  5  enters weft insertion channel  2   a  of reed  2 , weft  5  crosses the first reed filler  3  located in a stationary position in reed insertion position  11   a , then the weft insertion channel  2   a  of reed  2  that is in insertion position  11   a , and thus crosses on the output side of weft insertion channel  2   a  the thread channel  6   a  of second reed filler  6 . 
     Downstream from second reed filler  6  is auxiliary reed  7  with a first thread stop motion  8 , with auxiliary reed  7  serving to produce a so-called catch selvedge. Weft  5  then passes through thread channel  7   a  of an auxiliary reed  7 and is stretched by the weft-stretching and detecting device. Auxiliary reed  7  and the weft-stretching and detecting device  10  with a weft stop motion  10   a , like reed  2 , is permanently connected with the reed (not shown) that performs the oscillating movements of reed  2  in the direction of double arrow  11 . The first weft stop motion  8  integrated into auxiliary reed  7  signals the arrival of an inserted weft through lines  8 b to weaving machine control  12 . 
     The first weft stop motion  8  can be located on the output or input side of the auxiliary reed  7 . 
     It will be clear to the individual skilled in the art from the above that in addition to the necessary weft length for producing the so-called catch selvedge  9 , an additional length (L) is required to ensure detection of the arrival and/or detection of the correct weft insertion by the first weft stop motion  8  and corresponding signal via lines  8   a ,  8   b.    
     According to the state of the art presented with respect to FIG. 1, on the output side of auxiliary reed  7   a  weft-stretching and detecting device  10  is provided that comprises a second weft stop motion  10   a . The weft stop motion  10   a , when so-called “long shots” or “weft breakers” occur, interrupts the weaving process in conjunction with weaving machine control  12 . 
     FIG. 2 depicts a preferred embodiment of the invention. In FIG. 2, similar reference numbers as in the FIG. 1 embodiment, increased by 100, are used to depict similar features. Unless otherwise indicated below, the description of the corresponding feature for FIG. 1 applies. 
     In FIG. 2, according to the invention, the first weft stop motion  108  is integrated into the stationary reed filler  106 , which is located in weft insertion position  111   a  immediately on the output side of weft insertion channel  102   a . On the output side of weft channel  106   a  of reed filler  106  a technical unit is located that is composed of a combination of a known auxiliary reed  107  and a known weft-stretching and detecting device  110 , which is connected in the same way as reed  102  permanently with the reed stay of weaving machine  101 . 
     The location according to the invention of the first weft stop motion  108  in reed filler  106  thus results in a savings of weft length that corresponds to the length (L) of the weft stop motion  8  according to FIG. 1 integrated into reed filler  6 . 
     The solution according to the invention also achieves the advantage that the signal leads  108   a  and  108   b  of weft stop motion  108  that lead to weaving machine control  112  are not subject to any dynamic stress and hence the risk of the signal lead cables breaking is largely eliminated. 
     The operation of the weaving machine following insertion of the weft in weft insertion position  111   a  shown is as follows: 
     Reed  102  moves together with weft insertion device  104  and the technical unit consisting of auxiliary reed  107  and weft-stretching and detecting device  110 , in which weft  105  is held stretched, into the weft beating-up position  11   b  of reed  102 . In other words weft  105  is beaten up here against beating-up edge  113   a  of fabric  113  and then cut by scissors  114 , positioned on the one hand between weft insertion device  104  and tucking means  115  and cut by a scissors  116  positioned on the other hand between a tucking means  117  and technical unit  107 ,  110 . The ends of beaten-up weft  105  are grasped by the tucking means  115 ,  117  known of itself, guided back into a following shed, and beaten up with an additional weft firmly against fabric edge  113   a.    
     The foregoing disclosure has been set forth merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof.