Yarn planner for tufted patterns and creeling

Abstract

A tufting machine interface or simulator is provided with yarn planning software enabling the optimization of winding yarn cones for particular patterns and production runs to minimize waste yarn and labor attendant to rewinds.

Claims

1. A method for yarn planning in the manufacture of patterned tufted fabrics from pixel mapped designs comprising: loading a pixel-mapped design file for a pattern into a tufting machine interface or simulator; designating pattern characteristics including shift pattern and effective stitch rates; designating a production target by tufted fabric length or surface area; assigning yarns to the pattern; computing yarn consumption for each of a plurality of needles; selecting a group of yarns for analysis; determining the number of rewinds required at varying yarn cone weights for the group of yarns; determining the cost of labor for yarn rewinds and cost due to yarn waste from yarn cones having excess lengths of yarn; utilizing the determined cost to select a desired weight of yarn for cones used for the group of yarns.

2. The method of claim 1 wherein the steps of determining the number of rewinds required at varying yarn cone weights for a group of yarns, and determining the cost of labor for yarn rewinds and cost due to yarn waste from yarn cones having excess lengths of yarn to select a desired weight of yarn for cones used for the group of yarns, are repeated for each group of yarns used in the pattern.

3. The method of claim 1 wherein a tufting machine configuration is entered before computing yarn consumption for each of a plurality of needles.

4. The method of claim 3 wherein the tufting machine configuration includes the needle bar gauge and configuration.

5. The method of claim 4 wherein yarn consumption for each of a plurality of needles is displayed in length, weight, or both.

6. The method of claim 1 wherein yarn information including denier is provided before computing yarn consumption for each of a plurality of needles.

7. The method of claim 1 wherein a visual representation of yarn consumption by needle is displayed after computing yarn consumption for each of a plurality of needles.

8. The method of claim 1 wherein the group of yarns is selected by color.

9. The method of claim 1 wherein lengths of yarn feed increments are provided before computing yarn consumption for each of a plurality of needles.

10. The method of claim 1 wherein after computing yarn consumption for each of a plurality of needles for a group of yarns, the group of yarns is divided into a plurality of subgroups to better reduce the cost of salvaged yarns and labor attendant to rewinds.

11. The method of claim 1 wherein the cost of waste yarn and the labor cost of rewinds are input into the tufting machine interface or simulator and the desired weight of yarn cones used for the group of yarns is automatically computed.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The particular features and advantages of the invention as well as other objects will become apparent from the following description taken in connection with the accompanying drawings in which:

(2) FIG. 1A is a perspective view of a tufting machine and creel;

(3) FIG. 1B is a schematic diagram of a tufting machine and creel;

(4) FIG. 2 is a flow diagram illustrating exemplary steps presently used in designing and manufacturing tufted fabric;

(5) FIG. 3 is a flow diagram of exemplary steps in practicing a yarn planning method in connection with designing patterns to manufacturing tufted fabrics;

(6) FIG. 4 is an exemplary control screen display for the input of design and tufting parameters, especially in needle bar shift profile;

(7) FIG. 5 is an exemplary control screen display for computing yarn consumption based upon machine and yarn type configurations;

(8) FIG. 6 is an exemplary control screen display for analyzing waste and required rewinds for a variety of yarn cone winding options.

DETAILED DESCRIPTION OF THE INVENTION

(9) Turning then to FIG. 1A, a general depiction of the tufting machine 10 with take up rolls 19 for the tufted fabric and two-story creel 14 to hold cones of yarn is illustrated. It will be understood that the invention can be practiced on a wide variety of tufting machines, not simply the broadloom machine 10 represented in FIG. 1A. For instance, Colortec ICN machines and Colortron/iTron hollow needle tufting machines also have the capability to place yarns in individual pixel locations according to a pattern and thus are suitably adapted for use with the invention. In addition, the yarn creel set up is exemplary and yarns could be supplied to the tufting machine from a single-story creel or from beams that are wound for use in supplying yarns. In the typical case there will be hundreds of separate yarns fed from the creel, most frequently between about 600 and 1800 yarns and most commonly between about 1100 and 1700 yarns, although some machine and pattern combinations, such as relatively narrow hollow needle machines tufting patterns with a limited number of colors, could operate with a much smaller number and perhaps only about 200 yarns.

(10) The tufting machine 10 disclosed in FIG. 1B includes a rotary needle shaft or main drive shaft 11 driven by stitch drive mechanism 12 from a drive motor or other conventional means. Rotary eccentric mechanism 15 mounted upon rotary needle shaft 11 is adapted to reciprocally move the vertical push rod 16 for vertically and reciprocally moving the needle bar slide holder 17 and needle bar 18. The needle bar 18 supports a plurality of uniformly spaced tufting needles 20 in a longitudinal row, or staggered longitudinal rows, extending transversally of the feeding direction of the backing fabric or material 22. The backing fabric 22 is moved longitudinally in direction 21 through the tufting machine 10 by the backing fabric feed mechanism 23 and across a backing fabric support with needle plate and needle plate fingers.

(11) Yarns 25 are fed from the creel 14 to the pattern control yarn feed 26 to the respective needles 20. As each needle 20 carries a yarn 25 through the backing fabric 22, a hook is reciprocally driven by the looper drive 29 to cross each corresponding needle 20 and hold the corresponding yarn end 25 to form loops. Cut pile tufts are formed by cutting the loops with knives.

(12) The needle bar shifting apparatus 32 is designed to laterally or transversely shift the needle bar 18 relative to the needle bar holder 17 a predetermined transverse distance equal to the needle gauge or multiple of the needle gauge, and in either transverse direction from its normal central position, relative to the backing fabric 22, and for each stroke of the needles 20. It will be understood that the lateral displacement of needles relative to the backing fabric 22 may also be achieved by the use of a backing fabric shifter, or by the combination of a backing fabric shifter with needle bar positioners for one or more needle bars. When using a backing fabric shifter, the shifting may not be constrained to shifting in needle gauge increments, although is any given area of the fabric an effective gauge may be determined.

(13) In order to generate input encoder signals for the needle bar shifting apparatus 32 corresponding to each stroke of the needles 20, an encoder 34 may be mounted upon a stub shaft 35, or in another suitable location, and communicate positional information from which the tufting machine controller can determine the position of the needles in the tufting cycle. Alternatively, drive motors may use commutators to indicate the motor positions from which the positions of the associated driven components may be extrapolated by the controller. Operator controls 24 also interface with the tufting machine controller to provide appropriate instructions and pattern information.

(14) On a broadloom tufting machine, these components can be operated in a fashion to provide pixel-addressed yarn placement as described in various prior patents such as U.S. Pat. Nos. 6,439,141; 7,426,895; and 8,359,989 and continuations thereof. Pixel controlled yarn placement in connection with ICN machines is described in U.S. Pat. Nos. 5,382,723 and 5,143,003; while pixel controlled placement of yarns utilizing hollow needle tufting machines is described in U.S. Pat. Nos. 4,549,496 and 5,738,030. Similar yarn placement may be achieved utilizing backing shifting as is disclosed in PCT/US17/54683 filed Sep. 30, 2017. All these patents and applications are incorporated herein by reference.

(15) Turning then to the process of designing and manufacturing tufted fabric as reflected in FIG. 2, the first step 28 is the creation of a graphic design to be tufted. The design can be created by an artist or adapted from a photograph or preexisting image. In either case, the image should be created or processed to limit the color palette to a manageable number of yarn colors, preferably between two and twelve, and most commonly three to six colors.

(16) The next step 30 is to load the image into a tufting machine having a controller running a control software system such as the iTuft or Tuftworks system sold by Tuftco Corp. and to process the pattern graphics to create machine instructions. When using the iTuft system, there are two principal steps prior to creating machine instructions. One step 33 (in FIG. 2), carried out as reflected in FIG. 4, is to assign a shift pattern or step pattern 41 to the needle bar 37 (shown in FIG. 2) and a stitch rate to the pattern. In the case of a two-color pattern, it is quite practical to use a very simple stepping pattern of over and back so that the needle bar merely moves from dead center 42 to a position offset by one gauge unit 43 and then repeats. In this case, the repeat length 44 is only two steps. In the event that a four-color pattern was being tufted, typical stepping pattern would involve two steps to the right, four steps to the left, and two steps to the right. Variations of the shift profile for other numbers of colors utilized on a broadloom tufting machine are well known and easily computed. It can also be seen that the stitch rate 45 may be specified which can affect the density of yarn bights and the weight of the resulting tufted fabrics.

(17) In addition to entering the stepping pattern in FIG. 4, in the iTuft system the yarns and yarn feed increments are assigned to the colors in the graphic pattern 37 (in FIG. 2). In the prior art, at this point the pixel-mapped design can be translated into tufting machine instructions 39 and the tufting machine 10 operated to produce a tufted fabric of the design 40.

(18) Using the yarn planning techniques of the invention requires some modifications to the prior art process. The pixel-mapped design is created as before 28 but then the design file is loaded into a tufting machine, or more typically a desk top simulator 30 where the physical characteristics of the tufting machine have been stored, or may be specified. Then the shift pattern and stitch rate are set 33 and yarn feed increments assigned to colors in the design 37. After the pattern has been associated with yarns, yarn feed increments, and a stepping pattern for a particular tufting machine, it is then possible to compute the yarn consumption for each needle 71 as shown in FIG. 3. This calculation involves combining the lengths of yarn that are utilized in shifting yarns from one position to another in addition to the lengths of yarn that are actually fed and tufted into the backing fabric. This calculation varies depending upon the type of tufting machine, the needle bar gauge and configuration (single, staggered, graphics), lateral shifting mechanism(s) and stitch rates.

(19) Once the pattern details are input, then as depicted in screen display 50, initial steps in calculating yarn consumption involve the specification of the characteristics of the tufting machine 51. This tufting machine configuration may be uniform for some types of machines or may require specific machine information or preloaded configuration to be input. If the yarn planning software is being run on a particular tufting machine rather than at a remote workstation, the characteristics of that machine may be entered by default. In addition, the production target 52 will be specified and the stitch rate 53, thread-up 54, and yarn types 55. The yarn type will preferably include denier information so that yarn lengths can be converted to weights. Based upon the pattern information, machine information, and this production and yarn information, the yarn consumption for each needle can be computed 61 and graphically displayed 60. Then yarn consumption by thread can be analyzed in comparison to other threads and within a single thread group. Most commonly a thread group will be yarns of a particular color, so that A threads might be blue yarn, B threads might be green yarns, and C threads might be gray yarns. In other cases, the yarns in different thread groups may have the same color but differ in other ways such as weight/denier, twist, material, or treatment.

(20) This foregoing analysis of yarn consumption by thread might, for instance, disclose that the yarn cones for A threads should be wound to a different weight than B threads or the like. Alternatively, the analysis could make it obvious that A threads could be more efficiently divided into two subgroups, say A.sub.1 and A.sub.2, each subgroup wound to a distinct weight.

(21) Yarn consumption may be aggregated by yarn group 62, or subgroup, and the relative weight and percentage of each yarn group can be visualized. A variety of operations may be executed upon the yarn consumption data 63. For instance, after data is changed, yarn consumption by needle can be calculated 64. A report of this data may be printed, or that data can be saved, a set of saved data can be loaded, or the data can be cleared for the entry of new yarn plan data.

(22) Selecting the Order Calculator feature 65 generates the Yarn Plan Weight Analysis view 80 of FIG. 6. This view shows the needle or end count for each yarn group A, B, C, and D in the illustrated example. It is possible that patterns may have more or less yarn groups. The Calculate Weight functionality 81 generates the Cone Weight Analysis view 90. This view shows the various cone weights of yarn for the selected yarn group required for the production target—the largest, smallest, median, and average cone weights. The operator can then select the number of yarn cones that may be specially rewound to add yarn (or alternatively replaced during production—but in either case denominated a “rewind”) with a view to the total weight of wasted yarn. Weight is provided because the yarn denier is known, but in the absence of that information, the total length of yarn that would be “waste” for salvage purposes would be shown. The yarn cone weight analysis 90 provides an analysis of the number of yarn cone rewinds (or replacements) in comparison to the amount of waste yarn that must be salvaged after the production run.

(23) Based upon this information, the operator of the yarn planner software can select the most desirable yarn cone weight to result in minimization of the cost of salvaged yarn and labor attendant with rewinds during the production run. A particular carpet mill or particular tufting machine may have a predetermined cost of labor per rewind and a cost per pound for waste yarn so that overall cost of labor and yarn may be automatically minimized based on those inputs. The analysis also generates a ratio of the yarn cone weight selected to the average weight of all cones in the group. In the illustrated example, the highlighted weight for the yarn cones, requiring 5 rewinds, is 3.994 pounds. When this weight is divided by the average yarn weight required (2.777 pounds), it provides a factor or ratio of 1.438. This ratio may be used in future production planning for different target production lengths, to provide similarly useful results without repeating all of the calculations and decision process.

(24) It is anticipated that additional visual presentations of the yarn consumption data may be created. For instance, there may be some clusters of yarn cone weights that are particularly common in a pattern and that would justify dividing a single yarn group, such as the A yarns, in to two or more subgroups, such as A.sub.1 and A.sub.2. While this would complicate the loading of the creel, it could nonetheless provide valuable savings in waste yarn and rewinds.

(25) Accordingly, as reflected in FIG. 3, an optimized yarn planning process may involve creating a pattern 28, loading the pattern into a tufting machine or desktop simulator 30, designating the machine configuration 31, designating the shift pattern for the machine configuration (if not already included in the pattern file) 132, setting a stitch rate reflective of the number of yarn bights intended to be visible over a specified longitudinal distance of backing 33, designating a production objective 134, assigning yarns and yarn information to pattern colors (and specifying yarn feed increments if not already included in the pattern file) 37, computing yarn consumption by needle 71, optionally displaying visual representations of yarn consumption by needle or by yarn type 72, grouping yarn consumption by needle according to yarn type/color for analysis 73, selecting individual yarn types/colors to display analysis of yarn consumption across needles carrying the selected yarn 74, displaying an analysis of yarn waste and labor/rewinds attendant to different yarn cone weights/winding lengths 75, selecting a desired yarn cone weight/winding length for the individual yarn type/color 76, computing a salvage yarn ratio 77, repeating the selection and analysis of steps 74-77 for the remaining yarn types/colors in the pattern 78, using the resulting desired yarn cone weights/winding lengths to order yarn for the production 79.

(26) Numerous alterations of the structure herein disclosed will suggest themselves to those skilled in the art. However, it is to be understood that the present disclosure relates to the preferred embodiment of the invention which is for purposes of illustration only and not to be construed as a limitation of the invention. All such modifications which do not depart from the spirit of the invention are intended to be included within the scope of the appended claims.