Patent Publication Number: US-7717140-B2

Title: Narrow cranked heald

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The present application claims the priority of European Patent Application No. 07 014 643.6, filed Jul. 26, 2007, the subject matter of which, in its entirety, is incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     The invention relates to a flat ribbon heald with an end eyelet, shaft and thread eye, said heald being manufactured of a metal ribbon section. 
     Healds are manufactured, for example, of flat steel ribbon during a punching operation. In so doing, parts are removed from a specifically cut metal ribbon in order to obtain the desired exterior form of the heald. The removed parts are waste, which considerably contributes to the consumption of material. 
     At times, it is necessary to provide healds with a crank, in which case, in particular adjacent healds on a heald shaft are cranked, frequently away from each other in opposite direction. As a result of this, an offset is created between the thread eyes of adjacent healds relative to the longitudinal direction of the warp thread in order to facilitate the passage of warp threads between the healds. Paired healds having shafts with different offsets have been known from documents U.S. Pat. No. 7,204,274 B2, and CH 468 489 and DE 10 2005 033 175 B3. Each of these healds has a straight edge, respectively, extending along the shaft and the end eyelet. The achievable intermediate space between the shafts of adjacent healds is limited. 
     Furthermore, document U.S. Pat. No. 1,545,904 discloses the manufacture of healds of flat material that forms a relatively narrow sheet metal strip. The end eyelets adjoin the shaft in a symmetrical manner, whereby the shaft may be provided with a crank in order to define an enlarged thread passage space between adjacent healds. 
     Furthermore, document U.S. Pat. No. 2,973,789 discloses a heald set consisting of differently cranked healds, whereby the healds consist of a metallic flat material. Adjoining the end eyelets, the shafts of the healds are cranked and configured in such a manner that an enlarged thread passage space exists between adjacent healds. 
     Finally, document U.S. Pat. No. 644,371 discloses a heald that has been manufactured of a narrow steel strip, in which the thread eye and the end eyelet have been produced by spreading apart slotted sections. In addition, the shaft of such a heald may be cranked. During a stamping process, the shaft has been flattened on both sides of the thread eyelet in order to effect increased elasticity in longitudinal direction of the warp thread. 
     Indeed, the production of elongated openings by slitting and widening is a material-saving process; however, this requires a relatively strong material deformation, thus restricting the choice of material and the possibilities of material optimization. 
     It is the object of the invention to provide a heald and an economical manufacturing process for the production of said heald, this being intended to make possible a material-saving manufacture of high-performance healds. 
     SUMMARY OF THE INVENTION 
     This objective is achieved with the flat ribbon heald and the process for manufacturing the flat ribbon heald as disclosed herein: 
     The flat ribbon heald consists of a metal ribbon section having an original width corresponding to the width at the end eyelet. Material has been removed along the shaft, for example, during a stamping operation or the like. Between the end eyelet and the shaft is a transition section, in which the width is reduced from the end eyelet width to the shaft width. On its end eyelet, the heald has a straight edge that has—at some distance from the end eyelet, either at the transition section or at the shaft—a section extending away from the center line of the heald either in the form of a sharp bend or of an arc. As a result of this, the outer edge of the shaft is offset by an amount X. The center of the thread eye preferably is approximately on a line that connects the outside edges of the end eyelets with each other. 
     Such a heald can be manufactured of a metal strip having a width that is no greater than the width of the end eyelets. Nerveless, a large offset between the thread eye and the end eyelet may be achieved in longitudinal direction of the warp thread. 
     Starting with an initially flat ribbon heald—which is preferably planar, i.e., not twisted, and thus its end eyelet, transition section and shaft are located in a common plane, preferably not twisted relative to each other—the shaft is later arranged offset relative to the end eyelets. This offset of the shaft relative to the end eyelets, said offset not yet existing after the cutting out or punching out of the heald but being created later, is achieved by a plastic deformation of the transition region or of a part of the shaft within said plane. This is achieved by an appropriate stamping process. However, it is also possible to combine the punching and stamping steps in one step and to perform these with one tool. Also in this case, a plastic deformation on the shaft or on the transition region achieves the formation of a crank or offset. 
     Additional details of advantageous embodiments of the invention are obvious from the drawings, the description and the subclaims. The description is restricted to essential aspects of the invention and to miscellaneous situations. The drawings disclose additional details and are to be considered supplementary. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIGS. 1 and 2  show flat ribbon healds after having been punched out, however, before the cranking or stamping step. 
         FIG. 3  shows the superimposed flat ribbon heald blanks in accordance with  FIGS. 1 and 2 . 
         FIGS. 4 and 5  show the flat ribbon healds manufactured from blanks as in  FIGS. 1 and 2 , following a stamping step. 
         FIG. 6  shows the superimposed flat ribbon healds as in  FIGS. 4 and 5 . 
         FIGS. 7 and 8  illustrate alternative embodiments of flat ribbon healds, each depicted by two associate differently cranked superimposed healds. 
         FIG. 9  shows a modified embodiment of a flat ribbon heald in accordance with the invention, showing its end region. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIG. 1  shows a flat ribbon heald blank  1  that has been punched out of a metal ribbon having the width B. This width B is less than is usual for punched flat ribbon healds. The flat ribbon heald blank  1  has two end eyelets  2 ,  3 , with a shaft  4  provided between them. This shaft adjoins the end eyelets over transition regions  5 ,  6 . During the manufacture of the flat ribbon heald blank  1 , openings  7 ,  8  are applied to the end regions of the sheet metal strip section in order to form end eyelets  2 ,  3 . These openings may have a continuous edge or may also have, as shown, a discontinuous edge. Depending on this, O-shaped end eyelets (as in  FIG. 8 , for example) or C-shaped end eyelets (as in  FIGS. 1 through 6 ) or J-shaped end eyelets (as in  FIG. 7 ) are created. 
     The flat ribbon heald blank  1  has a straight edge  9 , which extends from the upper end of the upper end eyelet  7  to the lower end of the lower end eyelet  8 . This straight edge  9  corresponds to a lateral edge of the original metal ribbon section. However, at the end eyelets  2 ,  3 , only two sections  10 ,  11 , respectively, are still left opposite the straight edge. In a section located in-between, said section comprising the transitions regions  5 ,  6  and the shaft  4 , the material is removed from the metal ribbon section (e.g., by a punching or cutting process), thus creating inward-extending edge sections  12 ,  13  and an inward-offset edge section  14 . In addition, the shaft  4  has been provided with a thread eye  15 , in which an appropriate opening has been provided at the desired location. Additional openings  16 ,  17  may be provided on the end eyelets  2 ,  3  or in the transition regions  5 ,  6 . 
       FIG. 2  shows another flat ribbon heald blank  18 . While, in the case of the flat ribbon heald blank  1  the straight continuous edge  9  is located on the side of the edge interruption of the openings  7 ,  8 , this continuous edge  9  is provided on the other side of the blank in the case of the flat ribbon heald blank  18  in accordance with  FIG. 2  and thus extends continuously over the closed edges of the end eyelets  2 ,  3 . The sections  10 ,  11  are located on those sides of the end eyelets  2 ,  3  that have a discontinuous edge. The same applies to the edge sections  12 ,  13 ,  14 . Other than that, the description of the flat ribbon heald blank  1  applies analogously to that of the heald blank  18 , using the same reference numbers. 
     When the two heald blanks  1 ,  18  are superimposed, the appearance is as in  FIG. 3 . Remaining between the edge sections  14  is a distance D that is relatively small. Of course, the heald blanks  1 ,  18  may be installed as healds already in this state, however, due to the minimal distance D, there is the risk of damaging the warp threads that would have to pass between the heald blanks  1 ,  18 . 
     Therefore, the heald blanks  1 ,  18  move through another processing step, e.g., a stamping step, in the course of which they are being cranked outward away from each other, e.g., in the transition regions  5 ,  6 . In so doing, they are deformed within the plane defined by the end eyelets  2 ,  3  and the shaft  4  in such a manner that the thread eye  15  is located on an imaginary line  19 , as is marked by the former position of the edge  9 . This imaginary line  19  connects the remaining sections  9   a ,  9   b  of the edge  9  that are still present on the end eyelets  2 ,  3 . The center of the thread eye  15  is located on the line  19  or is bent outward beyond said line, i.e., to the left in  FIG. 4 . This thread eye is arranged in the center section  9   c  of the former edge  9 . This section  9   c  is located at a distance X from the line  19 . In so doing, the distance X is preferably as great as half the width B 1  of the shaft  4  in the region of the thread eye  15 . During the reforming process, the edge  9  is divided into sections, namely the sections  9   a ,  9   b , that are located on the line  19  and terminate in the sections  9   d ,  9   e , via an outward directed sharp bend or an arc, said latter sections extending from the line  19  and terminating in the central section  9   c , which, in turn, is straight again. 
     The manufacture of the thusly produced flat ribbon heald  20  requires less use of material, when compared with conventional healds provided with wider metal ribbon sections. Compared with healds having widened end eyelets, more minimal local material deformations occur. The material selection may be optimized. 
     A complementary flat ribbon heald  21  can be produced from the flat ribbon heald blank  18 . Again, a reformation process is used, in the course of which the center of the shaft  4  is brought onto the line  19  that marks the former course of the edge  9 . As a result of this, the edge  9  is divided into the sections  9   a ,  9   b ,  9   c ,  9   d ,  9   e . The above description of the flat ribbon heald blank  18  and the flat ribbon heald  20  applies analogously, using the same reference numbers. 
     When the flat ribbon healds  20 ,  21  are fittingly superimposed in the manner as they are lined up on the carrier rails as shown by  FIG. 6 , it is obvious that the shafts  4  are bent away from each other. Therefore, a distance R is created between the edge sections  14  of the shafts  4  in the region of the thread eyes  15 , said distance being substantially greater than the distance D in accordance with  FIG. 3 . Preferably, the distance R has a size that is half the width B 1  of the shaft  4 , ideally the same size as the width B 1  of the shaft  4 . 
       FIG. 7  shows a modified heald pair  22  with J-shaped end eyelets  2 ,  3 . Other than that, the above descriptions apply analogously, using the same reference numbers. 
       FIG. 8  shows a heald pair  23  with ring-shaped end eyelets  2 ,  3 . Again, the above description applies analogously. 
     While, in all of the above exemplary embodiments, the offset of the section  9   c  of the edge  9  is provided on the transition sections  5 ,  6 , it is also possible to move this offset into the region of the shaft  4 .  FIG. 9  shows such an example. While the transition region  5  reduces the width of the heald from the larger width B in the region of the end eyelet  2  to the amount of the smaller width A of the shaft  4 , the straight section  9   a  of the edge  9  extends over the end eyelet  2 , as well as over the transition region  5 . The adjoining shaft  4  is cranked, so that the section  9   d  of the edge  9  is located in the region of the shaft  4 . Also in this case the outward-facing section  9   d  directly adjoins the straight section  9   a  via an arc or a sharp bend. 
     The healds in accordance with the invention consist of a metal ribbon section having the width B that is narrower than the total width B+X required for the flat ribbon heald  20 . The flat ribbon heald  20  has an essentially non-machined—in any event, not trimmed—edge  9  derived from the metal ribbon section and an edge  10 ,  11 ,  12 ,  13 ,  14  that has been produced, in the region of the shaft  4  and the transition regions  5 ,  6 , by trimming the metal ribbon section. An outward-directed crank of the shaft  4  creates an enlarged distance R between two associate oppositely cranked flat ribbon healds of a heald pair  23  which comprises two oppositely cranked flat ribbon healds  20 ,  21 . 
     It will be appreciated that the above description of the present invention is susceptible to various modifications, changes and modifications, and the same are intended to be comprehended within the meaning and range of equivalents of the appended claims. 
     LIST OF REFERENCE NUMBERS 
     
         
           1  Flat ribbon heald blank 
           2 ,  3  End eyelets 
           4  Shaft 
           5 ,  6  Transition region 
           7 ,  8  Openings 
           9 ,  9   a - 9   d  Edge 
           10 ,  11  Sections 
           12 ,  13 ,  14  Edge sections 
           15  Thread eye 
           16 ,  17  Openings 
           18  Flat ribbon heald blank 
           19  Line 
           20 ,  21  Flat ribbon heald 
           22 ,  23  Heald pair