Method and apparatus for stitching material along a curve

• US 4,352,334 A
• Filed: 08/03/1981
• Issued: 10/05/1982
• Est. Priority Date: 08/03/1981
• Status: Expired due to Term

• Current Assignee: Melco Industries Incorporated (Oerlikon USA, Inc. (Florida))
• Original Assignee: Melco Industries Incorporated (Oerlikon USA, Inc. (Florida))
• Inventors: Childs, William R., Melton, Randall
• Primary Examiner(s): Nerbun, Peter P.
• Application Number:
  US06/289,825
• Time in Patent Office: 428 Days
• Field of Search: 112/266.1, 112/102, 112/103, 112/121.12, 112/158 E, 112/308, 112/309
• US Class Current: 112/475.19
• CPC Class Codes: D05B 21/00 Sewing machines with devices for automatically controlling movement of work-carrier relative to stitch-forming mechanism in order to obtain particular configuration of seam, e.g. programme-controlled for sewing collars, for attaching pockets

Abstract

A method and an apparatus are provided for stitching selected characters on material along a desired arc. A plurality of characters are stored in a character memory. The character memory communicates with a microprocessor which controls the operation of the apparatus. The microprocessor executes predetermined instructions stored in an EPROM while a RAM temporarily stores data required for proper apparatus operation. The characters selected for stitching along the arc are provided to the apparatus by the user. The radius of the arc along which the selected characters are to be stitched is also provided to the apparatus by the user. Each selected character has a reference position and is defined by a plurality of stitch locations having x, y coordinates. The mircroprocessor, in conjunction with the EPROM and RAM, rotates the stitch locations of the selected characters from the reference position to a rotated position using known and determined parameters of the selected characters and the inputted radius. By means of microprocessor control, stepping motors are activated to move a carriage assembly in x and y directions using the rotated stitch locations. The material to be stitched is connected to the carriage assembly and moves therewith. During non-movement of the carriage assembly, the material is stitched using the given and determined rotated stitch locations so that the selected characters are stitched on the material along the desired arc.

Claims

1. A method of stitching material along a curve using digital circuitry and memory means, comprising the steps of:

positioning the material to be stitched in a desired location relative to a threaded needle;

selecting one or more characters to be stitched along the curve from the memory means, all of the selected characters to be stitched being defined having a plurality of points in the memory means;

providing a magnitude of curvature of the curve along which each selected character is to be stitched;

determining the magnitude of an angle for each of the selected characters to be stitched, the magnitude of each angle of each selected character to be stitched determined using the magnitude of curvature;

sensing the position of the needle with respect to the material;

moving the material or the needle to determined locations when the needle is out of the material based upon a determination of stitch locations using each determined angle in order to stitch each selected character along the curve; and

stitching the material at the determined locations when the needle is in the material so that each selected character is stitched along the curve.

2. A method, as claimed in claim 1, wherein:

the magnitude of curvature includes a radius and the curve is a circular arc and in which each of the characters in the memory means has a width and each of the widths being defined independent of the provided radius.

3. A method of stitching material along a curve using digital circuitry and memory means, comprising the steps of:

positioning the material to be stitched in a desired location relative to a threaded needle;

selecting sequentially one or more characters to be stitched, all of the characters to be stitched being defined in memory means according to a first orientation;

providing a magnitude of curvature;

changing the characters from a first orientation to a second orientation using the magnitude of curvature, the magnitude of change of orientation of each selected character to be stitched depending upon all of the selected characters to be stitched and the magnitude of change of orientation of each selected character to be stitched depending upon the sequence of selection of characters to be stitched;

stitching the material using the threaded needle so that the selected characters are stitched according to the second orientation.

4. A method for stitching material along a curve using digital circuitry and memory means, comprising the steps of:

positioning the material to be stitched in a desired location relative to a threaded needle;

providing a radius;

selecting characters to be stitched from a plurality of characters stored in the memory means, each of the characters having a plurality of points, each of the characters having a character envelope being defined by at least a height and a width using at least some of the plurality of points, the height and width being defined independent of the provided radius;

obtaining a portion of one of the characters;

changing the orientation of the character portion using the radius and at least the width of the character envelope of the character whose portion was obtained;

moving a carriage to which the material is connected to a location depending upon the changed in orientation character portion;

stitching the changed in orientation character portion on the material.

5. An apparatus for use in stitching characters on material along a curve, comprising:

first means for storing a plurality of characters, each of said characters being defined by a plurality of points, each of said points being defined by at least two coordinates, at least two of said coordinates of each of said characters for use in defining a character width;

input means for use in providing a magnitude of curvature;

second means communicating with said first means and said input means for changing the magnitude of at least one of said coordinates of one of said points of one of said characters, said second means including means for determining an angle associated with said one of said characters using the magnitude of curvature and the character width of said one of said characters, the determined angles being used in changing the magnitude of said one of said coordinates;

third means responsive to said second means for stitching at least one of said characters along the curve using said changed magnitude of said one of said coordinates.

6. An apparatus as claimed in claim 5, wherein said third means includes:

means for moving the material with respect to the threaded needle, said means for moving includes at least a first stepping motor and a second stepping motor, said first stepping motor being activated to move the material in a first direction and said second stepping motor being activated to move the material in a second direction.

7. An apparatus for stitching characters on material along a curve using a threaded needle, comprising:

means for storing a plurality of characters, each of said characters being defined by at least one point having a first coordinate and a second coordinate;

means for inputting sequentially selected characters and for inputting a magnitude of curvature of the curve along which the selected characters are to be stitched;

means responsive to said inputting means for selecting said selected characters from said storing means, each of said selected characters having a width;

means communicating with said storing means for changing in magnitude said first coordinate and said second coordinate of said one point using said magnitude of curvature, the magnitude of change of said first coordinate and said second coordinate depending upon the widths of all selected characters and the sequence of selection of said selected characters and the determination of the magnitude of change of said first coordinate and said second coordinate being different than the determination of the magnitude of change of coordinates of any other selected character;

means responsive to said rotating means for moving the material using said changed in magnitude first coordinate and said changed in magnitude second coordinate; and

means communicating with said changing means for sensing the position of the threaded needle with respect to the material to be stitched.