SEWING MACHINE, STITCH DATA GENERATING DEVICE AND STITCH DATA GENERATING PROGRAM

Abstract

A sewing machine which forms stitches on a first object to be sewn based on stitch data, includes an imaging unit which images an outline of an upper cloth as the first object onto a lower cloth as a second object, obtaining image data, an outline calculation unit which calculates the outline of the upper cloth from the image data obtained by the imaging unit, a determination unit which determines a stitch-forming region for sewing the upper cloth onto the lower cloth based on the outline of the upper cloth calculated by the outline calculation unit, and a stitch data generating unit which generates stitch data for the stitch-forming region determined by the determination unit.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2011-043953 filed on Mar. 1, 2011, the entire contents of which are incorporated herein by reference.

BACKGROUND

1. Technical Field

The present disclosure relates to a sewing machine which forms stitches on an object to be sewn, such as a workpiece cloth, based on stitch data, a stitch data generating device which generates the stitch data and a computer-readable medium which stores a stitch data generating program.

2. Related Art

There has conventionally been known a sewing machine which can perform embroidery sewing and which is provided with a stitch forming mechanism including a needle, a transfer mechanism for moving an embroidery frame holding a workpiece cloth in X and Y directions on a sewing bed, and a control device which controls the stitch forming mechanism and the transfer mechanism. The control device controls the stitch forming mechanism and the transfer mechanism based on embroidery data indicative of amounts of movement of the embroidery frame in the X and Y directions for every stitch, so that an embroidery pattern according to the embroidery data is sewn onto the workpiece cloth.

On the other hand, a sewing machine has also been provided which sews, onto a lower cloth, an upper cloth such as a label or patch with the use of the above-described sewing machine. The sewing machine comprises a CCD camera which images the upper cloth temporarily tacked on the lower cloth. The sewing machine identifies an outline of the cloth from an image obtained by the CCD camera and generates stitch data for forming stitches along the outline. The control device then controls the stitch generating device and the transfer mechanism according to the stitch data thereby to execute an operation of sewing the upper cloth onto the lower cloth.

There is sometimes a case where a pocket is desired to be formed on a front of clothes such as Western-style clothes when the clothes are sewn by the use of a sewing machine. In this case, a sewing operation is executed so that stitches are formed along an outline of the pocket cloth after the pocket cloth (or an upper cloth) has been temporarily tacked on the front (or a lower cloth) of the clothes. The user carries out the sewing while changing a sewing direction by turning or moving the front of the clothes with the temporarily tacked pocket cloth relative to a needle bar (a needle) of the sewing machine. However, a user unfamiliar with the sewing machine would have a difficulty in sewing the pocket cloth onto the front of the clothes.

In view of the problem, the above-described conventional sewing machine has been considered to be applied to the sewing of pocket cloth. In this case, the pocket cloth needs to be sewn onto the clothes except for a part thereof serving as a pocket opening. However, the above-described conventional sewing machine has been found unsuitable for the sewing of the pocket cloth since the part of the pocket opening is also sewn as well as the other part of the pocket cloth.

SUMMARY

Therefore, an object of the disclosure is to provide a sewing machine which can automatically execute a work of sewing the upper cloth onto the lower cloth based on stitch data and can determine a region of the upper cloth to be sewn. Another object of the disclosure is to provide a stitch data generating device which can generate stitch data for the sewing machine and a computer-readable medium which stores a stitch data generating program for the stitch data generating device.

The present disclosure provides a sewing machine which forms stitches on a first object to be sewn based on stitch data, comprising an imaging unit which images an outline of an upper cloth as the first object onto a lower cloth as a second object, thereby obtaining image data; an outline calculation unit which calculates the outline of the upper cloth from the image data obtained by the imaging unit; a determination unit which determines a stitch-forming region for sewing the upper cloth onto the lower cloth based on the outline of the upper cloth calculated by the outline calculation unit; and a stitch data generating unit which generates stitch data for the stitch-forming region determined by the determination unit.

The disclosure also provides a stitch data generating device which generates stitch data for a sewing machine which forms stitches on a first object to be sewn based on stitch data, the device comprising an imaging unit which images an outline of an upper cloth as the first object to be sewn onto a lower cloth serving as a second object, thereby obtaining image data; an outline calculation unit which calculates the outline of the upper cloth from the image data obtained by the imaging unit; a determination unit which determines a stitch-forming region for sewing the upper cloth onto the lower cloth based on the outline of the upper cloth calculated by the outline calculation unit; and a stitch data generating unit which generates stitch data for the stitch-forming region determined by the determination unit.

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings:

FIG. 1 is a perspective view of an overall sewing machine according to a first embodiment;

FIG. 2 is a left side view of a sewing machine head, showing a state in which a camera is disposed;

FIG. 3 is a block diagram showing an electrical arrangement of the sewing machine;

FIG. 4 illustrates three types of pocket clothes with different configurations;

FIG. 5 illustrates three types of patterns of reinforcing stitches;

FIG. 6 is a flowchart showing a processing procedure for generation of stitch data executed by a control device; and

FIG. 7 is a perspective view of a stitch data generating device according to a second embodiment.

DETAILED DESCRIPTION

A first embodiment will be described with reference to FIGS. 1 to 6. Referring to FIG. 1, an overall construction of the sewing machine 1 according to the first embodiment, as viewed from the front thereof (the user side) is shown. In the following description, the side where the user who operates the sewing machine stands will be referred to as “front” and the opposite side will be referred to as “back.” The front-back direction thereof will be referred to as “Y direction” as shown in FIG. 1. Furthermore, the side where a pillar 3 is located will be referred to as “right” and the opposite side will be referred to as “left.” The right-left direction of a sewing machine 1 will be referred to as “X direction.”

The sewing machine 1 includes a sewing machine bed 2 extending in the right-left direction (X direction) as viewed in FIG. 1, the pillar 3 extending upward from a right end of the sewing machine bed 2 and an arm 4 extending leftward from an upper end of the pillar 3, all of which are formed integrally with the sewing machine 1. The arm 4 has a distal end serving as a sewing machine head 5. The head 5 includes a needle bar 6 which is mounted so as to be movable upward and downward and swingable in the right-left direction as shown in FIG. 2 as well as FIG. 1. The needle bar 6 has a lower end to which a needle 7 is attached. A presser bar 8 is mounted on the head 5 so as to be located in the rear of the needle bar 6 as shown in FIG. 2. The presser bar 8 has a lower end to which a presser foot 9 is mounted.

A known presser driving mechanism (not shown) is provided in the head 5 and includes a presser drive motor 10 (see FIG. 3) serving as a drive source of the presser driving mechanism. The presser driving mechanism moves the presser foot 9 or the presser bar 8 between an upper position and a lower position. In the arm 4 are provided a main shaft rotated by a sewing machine motor 11 and a main shaft angle detector 12 (see FIG. 3) which detects a rotation angle of the main shaft. A needle bar driving mechanism is provided in the head 5 to move the needle bar 6 upward and downward by the drive of the sewing machine motor 11 or the main shaft. Additionally, a needle bar swinging mechanism includes a needle swinging pulse motor 13 (see FIG. 3) serving as a drive source and swings the needle bar 6 in the right-left direction or the X direction.

A cover 4a is mounted on an upper part of the arm 4 so as to be openable and closable. A needle thread spool 14 is detachably set inside the cover 4a in the arm 4 in order to supply a needle thread. A plurality of operation switches 15 is provided on a lower front of the arm 4. These operation switches 15 include a start/stop key, a back stitch key, a needle up/down key, a thread cut key, a presser up/down key and a speed adjusting knob although a detailed description of these keys and knob will be eliminated.

A large-sized vertically-long full-color liquid crystal display (LCD) 16 serving as a display unit is mounted on the front of the pillar 3. A touch panel 17 is mounted on the surface of the LCD 16. When depressing the touch panel 17, the user can select a desired one of ordinary patterns and embroidery patterns or cause the sewing machine 1 to execute various functions about sewing. Furthermore, the user can also select a reinforcement stitch pattern on the touch panel 17 as will be described later. The touch panel 17 thus serves as a setting unit which sets a reinforcement stitch pattern.

A needle plate (not shown) is mounted on the upper surface of the bed 2 so as to correspond to the needle bar 6. A shuttle mechanism, a feed dog driving mechanism and the like are provided in the bed 2 so as to be located below the needle plate although none of them are shown. The shuttle mechanism accommodates a bobbin and serves to form stitches on a cloth as an object to be sewn in cooperation with the needle 7. The shuttle mechanism and the feed dog driving mechanism are driven by the sewing machine motor 11 serving as a drive source. Thus, a stitch forming unit which forms stitches on the object comprises the sewing machine motor 11, the needle bar driving mechanism and the shuttle mechanism.

A known embroidering apparatus 18 is detachably mounted on a left part of the bed 2. When mounted on the bed 2, the embroidering apparatus 18 is electrically connected via a connector 24 (see FIG. 3) provided in the bed 2 to a control device 25 of the sewing machine 1. The embroidering apparatus 18 includes a carriage (not shown) to which is detachably attached an embroidery frame 19 serving as a holding member for holding the cloth. The embroidering apparatus 18 also includes a transfer unit which freely moves the embroidery frame 19 holding the cloth in two predetermined directions or in an X direction (a right-left direction) and a Y direction (front-back direction) on the bed 2.

More specifically, the embroidering apparatus 18 includes a body 20 which is attached to the bed 2 and a moving member 21 which is long in the front-back direction and is movable in the right-left direction (X direction). The carriage is mounted on a right side surface of the moving member 21 so as to be movable in the front-back direction (the Y direction). The embroidery frame 19 is detachably attachable to the carriage. The embroidering apparatus 18 is configured so that the moving member 21 is freely moved in the right-left direction (the X direction) by an X-axis motor 22 (see FIG. 3) mounted in the body 20 and so that the carriage or the embroidery frame 19 is freely moved in the front-back direction (the Y direction) by a Y-axis motor (see FIG. 3) incorporated in the moving member 21. An auxiliary table is detachably attached to the bed 2 with the embroidering apparatus 18 being detached although not shown.

The sewing machine 1 having the above-described construction is capable of executing an embroidery sewing operation on the cloth by driving the needle bar 6 serving as the aforementioned stitch forming unit, and the like while the embroidery frame 19 holding the object is freely moved in the X and Y directions. The sewing machine 1 is provided with a function of automatically executing a pocket sewing work in which a pocket cloth P serving as the upper cloth and further as the object to be sewn is sewn onto a lower cloth C serving as the object by using the embroidering apparatus 18, as shown in FIG. 1. The lower cloth C is here assumed to be a cloth of the front of clothes, for example.

In the pocket sewing work, the embroidery frame 19 is attached to the carriage of the embroidering apparatus 18 while the lower cloth C with the pocket cloth P being tacked thereon by dress pins (not shown) is held on the embroidery frame 19. Based on stitch data for sewing the pocket cloth P, the embroidering apparatus 18, the needle bar 6 and the like are controlled so that stitches S are formed along the outline of the pocket cloth P while the embroidery frame 19 is freely moved. In this case, the stitch data is mainly composed of data of an amount of movement of the embroidery frame 19 per stitch, that is, data of amounts of movement of the lower cloth C held on the embroidery frame 19 in the X and Y directions.

The above-described sewing machine 1 is further provided with a function of generating stitch data necessary for execution of the pocket sewing work as will be described in detail later. A camera 26 serving as an imaging unit is provided on the sewing machine 1 for generating stitch data, as shown in FIG. 2. The camera 26 comprises a CMOS image sensor, for example and is mounted in the head 5 so as to be directed downward, thereby imaging the pocket cloth P temporarily tacked on the lower cloth C held on the embroidery frame 19.

FIG. 3 schematically shows an electrical arrangement of the sewing machine 1. A control device 25 controlling an entire sewing machine 1 is mainly composed of a microcomputer including a CPU 27, a ROM 28, a RAM 29, an EEPROM 30, an input interface 31 and an output interface 32 all of which are connected to one another by a bus bar 33. The ROM 28 stores a control program for controlling a sewing operation, a stitch data generating program as will be described later, various data necessary for a sewing operation, and the like.

The aforementioned main shaft angle detector 12, the touch panel 17 and the operation switches 15 are connected to the input interface 13. Operation signals generated by these elements or components are supplied to the control device 25. Furthermore, an image processing section 34 executes image processing such as binarization is applied to image data obtained by the camera 26. The image data processed by the image processing section 34 is supplied via the input interface 31 to the control device 25. The display 21 is connected via a drive circuit 35 to the output interface 32. The sewing machine motor 11, the needle swinging pulse motor 13, and the presser driving motor 10 are also connected via respective drive circuits 36, 37 and 38 to the output interface 32. The control device 25 executes a sewing operation while controlling the aforementioned detector 12, the touch panel 17, the operation switches 15, the camera 26, the display 21, the sewing machine motor 11, the needle swing pulse motor 13, the presser drive motor 10 and the like. The aforementioned connector 24 is also connected to the output interface 32, whereby the control device 25 controls the aforementioned mechanisms of the sewing machine 1 to execute the sewing operation.

The control device 25 executes a software configuration, that is, the stitch data generating program thereby to realize a function of a stitch data generating device which automatically generates stitch data necessary for sewing the pocket cloth P onto the lower cloth C, together with the camera 26. In this case, the camera 26 functions as an imaging unit, and the control device 25 functions as an outline calculation unit, a determination unit and a stitch data generating unit. Furthermore, the control device 25 automatically executes a pocket sewing operation based on the generated stitch data. The stitch data generating program may be stored on an external storage medium such as an optical memory disc, a magnetic disc, a flash memory or a USB memory, for example, so as to be loaded from the external storage medium to the control device 25.

More specifically, the user attaches to the embroidery frame 19 the lower cloth C with the pocket cloth P being temporarily tacked thereon, for example, by the dress pins, whereby the lower cloth C is held on the embroidery frame 19. Upon execution of the stitch data generating program, the control device 25 firstly executes an imaging routine of moving the embroidery frame 19 to a predetermined imaging location and thereafter imaging the outline of the pocket cloth P temporarily tacked on the lower cloth C by the camera 26.

The control device 25 then executes an outline calculation or computation routine of calculating the outline of the pocket cloth P from the image data of the pocket cloth P imaged by the camera 26. In the outline calculation, an edge of the pocket cloth P which is a boundary between the lower cloth C and the pocket cloth P is obtained from the obtained image data, and locations of feature points are extracted in an outline of the pocket cloth P. In this case, the feature points include an intersection (an apex) of two straight lines, a contact point between a straight line and a curved line or a contact point or an inflection point in the case where plural curved lines are continuous.

FIGS. 4A to 4C exemplify three typical forms of the pockets P respectively. The pocket cloth P shown in FIG. 4A has a pentagonal shape with a downwardly slightly sharp-pointed lower hem. Five feature points F1 to F5 are obtained in the case of FIG. 4A. The pocket cloth P shown in FIG. 4B basically has a rectangular shape with right and left curved (arc-shaped) corners of a lower hem. Six feature points F1 to F6 are obtained in the case of FIG. 4B. The pocket cloth P shown in FIG. 4C basically has a rectangular shape but right and left corners of the lower hem are cut out into obliquely straight lines such that the pocket cloth P has a hexagonal shape. Six feature points F1 to F6 are obtained in the case of FIG. 4C. Arrangement patterns of these three types of feature points F1 to F5 or F6 are stored as template data on the ROM 28.

Next to the above-described outline calculation routine or feature point extraction routine, the control device 25 executes a determination routine of determining a stitch-forming region provided for sewing the pocket cloth P onto the lower cloth C. In the determination routine, a region where stitches are to be formed (a region to be sewn) and a region where no stitches are to be formed (a region not to be sewn) are determined with respect to the outline or a periphery of the pocket cloth P. The region other than an upper edge or hem defining the pocket opening is determined as a stitch-forming region, and the upper edge defining the pocket opening is determined as a region not to be sewn. More specifically, the extracted feature points are compared with the template data stored on the ROM 28 so that the upper edge defining the pocket opening of the pocket cloth P is discriminated, and a stitch-forming region along the outline other than the upper edge defining the pocket opening is determined. Thus, the periphery of the pocket cloth P includes a first part corresponding to the stitch-forming region and a second part corresponding to the region not to be sewn.

In the example shown in FIG. 4A, a straight section obtained by connecting the feature points F5 and F1 is determined as an upper edge or hem defining a pocket opening in which no stitches are to be formed. Four straight sections obtained by connecting the feature points F1, F2, F3, F4 and F5 sequentially are determined as a stitch-forming region. In the example shown in FIG. 4B, a straight section obtained by connecting the feature points F6 and F1 is determined as an upper edge or hem defining a pocket opening in which no stitches are to be formed. Three straight sections and two curved sections obtained by connecting the feature points F1, F2, F3, F4, F5 and F6 sequentially are determined as a stitch-forming region. In the example shown in FIG. 4C, a straight section obtained by connecting the feature points F6 and F1 is determined as an upper edge or hem defining a pocket opening in which no stitches are to be formed. Five straight sections obtained by connecting the feature points F1, F2, F3, F4, F5 and F6 sequentially are determined as a stitch-forming region.

Upon determination of the stitch-forming region, the control device 25 executes a stitch data generating routine which generates stitch data according to which the determined stitch-forming region or a region along the contour of the pocket cloth P is sewn onto the lower cloth C by the forming of stitches S (see FIGS. 5A to 5C) in a predetermined pattern. The generated stitch data is stored on the EEPROM 30 or the like. In the embodiment, the control device 25 also has a function as a reinforcement stitch data generating unit which generates reinforcement stitch data for forming reinforcement stitches on both ends of the upper edge or hem of the pocket cloth P defining the pocket opening respectively.

FIGS. 5A to 5C show three examples of reinforcement stitch patterns formed on both ends of the upper edge of the pocket cloth P defining the pocket opening respectively. FIG. 5A shows right triangular reinforcement stitch patterns R1 formed on the pocket cloth P. The reinforcement stitch patterns R1 are continuous from both ends of the stitch pattern S and turn at a right angle at upper ends of the pocket cloth P, extending inward, respectively. The reinforcement stitch patterns R1 thereafter return diagonally so as to partially overlap the reinforcement stitch pattern S. FIG. 5B shows generally C-shaped reinforcement stitch patterns R2 formed on the pocket cloth P. The C-shaped reinforcement stitch patterns R2 are continuous from both ends of the stitch pattern S and turn at a right angle at upper ends of the pocket cloth P, extending inward, respectively. The reinforcement stitch patterns R2 thereafter extend downward. FIG. 5C shows bar tacking reinforcement stitch patterns R3 formed on the pocket cloth P. The reinforcement stitch patterns R3 are formed by partially overlapping zigzag chain stitches on both ends of the reinforcement stitch pattern S respectively. It is needless to say that the reinforcement stitch pattern may be any pattern other than those exemplified in FIGS. 5A to 5C.

The user can select the forming of reinforcement stitches or the non-forming of stitches, for example, by operating the touch panel 17. In this case, the ROM 28 stores data of the above-described three reinforcement stitch patterns R1 to R3. When forming reinforcement stitches, the user operates the touch panel 17 to set or select a desired one of the three reinforcement stitch patterns R1 to R3. Thus, the ROM 28 serves as a storage unit and the touch panel 17 serves as a setting unit.

The operation of the sewing machine 1 thus constructed will be described with reference to FIG. 6 as well as FIGS. 1 to 5C. In execution of a pocket sewing work, the user attaches the lower cloth C with the pocket cloth P being tacked thereon by the dress pins to the embroidery frame 19 so that the lower cloth C is held by the embroidery frame 19. The embroidery frame 19 is then set to the carriage of the embroidering apparatus 18. The stitch data generating program is then executed. As a result, a stitch data generating processing is firstly carried out for execution of a work of sewing the pocket cloth P onto the lower cloth C.

FIG. 6 is a flowchart showing the procedure for generating stitch data executed by the control device 25. More specifically, the lower cloth C and the pocket cloth P both located inside the embroidery frame 19 are imaged by the camera 26 at step S1 while the embroidery frame 19 occupies a predetermined imaging location (an imaging routine). Image data obtained by the camera 26 is processed by the image processing section 34 (binarization) thereby to be supplied to the control device 25. The outline of the pocket cloth P is calculated at step S2, and the feature points of the outline of the pocket cloth P are extracted at step S3 (the outline calculation routine).

The extracted outline of the pocket cloth P or the feature points are compared with the template at step S4. In this case, arrangement patterns of the three types of feature points F1 to F5 or F6 are stored as template data as exemplified in FIGS. 4A to 4C. The control device 25 determines with which one of the three arrangement patters the arrangement pattern of feature points extracted at step 33 corresponds. When the extracted arrangement pattern corresponds with one of the three arrangement patters (YES at step S5), the control device 25 proceeds to step S6 to determine a stitch-forming region (the determination routine).

In the determination of the stitch-forming region, the control device 25 determines, as a stitch-forming region, four straight sections obtained by connecting the feature points F1, F2, F3, F4 and F5 sequentially except for the upper edge or hem defining the pocket opening or the straight section between the feature points F5 and F1, in the case of the pattern as shown in FIG. 4A. In the case of the pattern as shown in FIG. 4B, the control device 25 determines, as a stitch-forming region, three straight sections and two curved sections obtained by connecting the feature points F1, F2, F3, F4, F5 and F6 sequentially except for the upper edge or hem defining the pocket opening or the straight section between the feature points F6 and F1. In the case of the pattern as shown in FIG. 4C, the control device 25 determines, as a stitch-forming region, five straight sections obtained by connecting the feature points F1, F2, F3, F4, F5 and F6 sequentially except for the pocket opening or the straight section between the feature points F6 and F1.

On the other hand, when the extracted arrangement pattern or the outline of the pocket cloth P corresponds with none of the three arrangement patters (NO at step S5), the control device 25 proceeds to step S7 to control the LCD 16 so that a message, “The stitch-forming region cannot automatically be determined.” is displayed. In this case, when the user operates the touch panel 17 to designate a stitch-forming region, the stitch-forming region is manually determined by the user (YES at step S8). In this case, the control device 25 is allowed to proceed to next step S9.

Upon determination of the stitch-forming region, stitch data is generated at step S9 (a stitch data generating routine). As the result of the processing at step S9, the control device 25 generates stitch data according to which the determined stitch-forming region or a region along the contour of the pocket cloth P except for the section defining the pocket opening is sewn onto the lower cloth C by the forming of stitches S along the outline of the pocket cloth P, as shown in FIGS. 5A to 5C. The control device 25 then proceeds to step S10 to determine whether or not the reinforcement stitches should be formed. In this determination, the LCD 6 displays a selection screen as to whether or not reinforcement stitches are formed. When no reinforcement stitches are to be formed (NO at step S10), the control device 25 finishes the processing.

When the reinforcement stitches are to be formed (YES at step S10), processing is performed at step S11 so that a reinforcement stitch pattern is set by the user. In this case, the user operates the touch panel 17 to select a desired one of the three types shown in FIGS. 5A-5C, that is, the right triangle R1, the C-shape R2 or the bar tacking R3 (YES at step S11). At next step S12, the control device 25 adds, to the aforementioned stitch data, the reinforcement stitch data for forming the selected reinforcement stitch patterns on the respective ends of the section defining the pocket opening, finishing the processing.

Subsequently, the control device 25 controls the sewing machine 1 so that a sewing operation is executed on the basis of the generated stitch data, whereby the pocket cloth P can be sewn onto the lower cloth C. In this case, no stitches are formed on the section of the pocket cloth P defining the pocket opening. Furthermore, the generated stitch data may be stored on the EEPROM 30 or an external storage medium, for example. When the pocket cloth P with the same shape as the previously sewn one is again sewn onto another lower cloth (the front of the clothes) or when the same clothes as the previously made one is again made, the stitch data stored on the EEPROM 30 or the external storage medium is loaded such that a sewing work can easily be executed.

In the above-described embodiment, the sewing machine 1 can automatically sew the pocket cloth P serving as the upper cloth onto the lower cloth C based on the stitch data. In the sewing machine 1, stitch data can be generated only for the stitch-forming region of the outline of the pocket cloth P or the region which is to be sewn onto the lower cloth P. More specifically, data of stitches to be formed along the outline of the pocket cloth P is generated although no stitch data is generated regarding the side of the pocket cloth P defining the pocket opening. The sewing is executed based on thus generated stitch data, whereupon the stitches S are formed on the region except for the section defining the pocket opening. Consequently, the pocket cloth sewing work can desirably be carried out without the side defining the pocket opening being sewn.

Furthermore, particularly in the foregoing embodiment, the reinforcement stitch data for forming the reinforcement stitches R1 to R3 can be added to the aforementioned stitch data. Consequently, the pocket cloth sewing work can further desirably be carried out. Additionally, since the pattern of the reinforcement stitch R1, R2 or R3 desired by the user can easily be set and formed, a reinforcement stitch according to user's preference can be formed.

FIG. 7 shows an appearance of the stitch data generating device 41 according to a second embodiment. The stitch data generating device 41 is configured to be independent of the sewing machine. More specifically, the stitch data generating device 41 is configured to generate stitch data for use with an ordinary sewing machine which is not provided with a function as the stitch data generating device including the camera 26 and which can execute embroidery sewing. Stitch data generated by the stitch data generating device 41 may be read via an external storage medium into the sewing machine, or the stitch data generating device 41 and the sewing machine may be linked together by wired or wireless connection for transfer of stitch data.

The stitch data generating device 41 is composed of a computer and more specifically comprises a device body 42 further comprising a general purpose personal computer and a camera 43 serving as the imaging unit and connected to the device body 42. The lower cloth C on which the pocket cloth P serving as the upper cloth is temporarily tacked by the dress pins (not shown) is held on the embroidery frame 19 and then imaged by the camera 43. The stitch data is generated based on an image obtained by the camera 43.

The device body 42 includes a CPU, a ROM, a RAM, an input-output interface and an operational circuit which functions as the outline calculation unit, the determination unit and the stitch data generating unit. The device body 42 also includes a keyboard 44 and a mouse both serving as setting units respectively, a display device 45 and a hard disc drive which functions as a storage unit. The device body 42 further includes a disc drive which performs reading and writing data from and onto a CD-ROM, a DVD and the like, for example, and a connector (a port) to which a flash memory or a USB memory is connected. The stitch data generating program may be stored on the hard disc drive. Alternatively, the stitch data generating program may be stored on an external storage medium such as a CD-ROM, a DVD, a flash memory or a USB memory and may be retrieved from the external storage medium.

The camera 43 may be a USB camera which necessitates no driver and comprises a CMOS camera which is directly connectable to the USE connector of the device body 42, for example. In use, the camera 43 is mounted to a support pillar (not shown) so as to be located above the embroidery frame 19 and so as to be directed downward, as shown in FIG. 7. The pocket cloth P temporarily tacked on the lower cloth C is imaged by the camera 43. Image data obtained by the camera 43 is supplied to the operational circuit of the device body 42.

The operational circuit of the device body 42 runs the stitch data generating program to execute the imaging routine of imaging the outline of the pocket cloth P by the camera 43. Subsequently, the operational circuit executes the outline calculation routine of calculating the outline of the pocket cloth P from the image data obtained by the camera 43, thereby determining a stitch-forming region which is used to sew the pocket cloth P onto the lower cloth C. Subsequently, the operational circuit executes the stitch-forming region determining routine of determining the region other than the edge or hem defining the pocket opening, as the stitch-forming region. The operational circuit further executes a stitch data generating routine of generating stitch data according to which the determined stitch-forming region along the outline of the pocket cloth P is to be sewn onto the lower cloth C by the forming the pattern of stitches S along the outline of the pocket cloth P. The operational circuit still further executes a user-designated reinforcement stitch adding routine.

In the second embodiment, the stitch data generating device 41 can also generate the stitch data for use with the sewing machine which can realize an automatic work of sewing the pocket cloth P as the upper cloth onto the lower cloth C based on the stitch data, as in the first embodiment. Consequently, the stitch data can be generated with respect to only the pocket cloth outline region which is to be sewn onto the lower cloth C. Thus, when executing the sewing based on the stitch data, the sewing machine can desirably sew the pocket cloth P onto the lower cloth C without sewing the edge of the pocket cloth defining the pocket opening.

Furthermore, it is needless to say that the above-described advantageous effects can also be achieved when the stitch data generating program is stored on an external storage medium and is run by the stitch data generating device 41.

The foregoing embodiments should not be restrictive, and various expanded and changed forms may be possible. For example, although the reinforcement stitch data is generated and added to the stitch data in the foregoing embodiments, the reinforcement stitch data generating unit (the routine) may or may not be provided. When the reinforcement stitch data is generated, the reinforcement stitch pattern should not be limited to the above-described three types as shown in FIGS. 5A to 5C. Other stitch patterns or a single stitch pattern may be employed, instead.

When being loaded into the stitch data generating device, the stitch data generating program may be supplied from a storage medium such as a flash memory or a memory card to the stitch data generating device. Alternatively, the stitch data generating program may be downloaded externally through a network or the like directly to the stitch date generating device. Furthermore, the camera 26 may be mounted on an outer surface of the arm. Thus, various changes may be made regarding the mechanical configurations of the sewing machine and the stitch data generating device.

The foregoing description and drawings are merely illustrative of the present disclosure and are not to be construed in a limiting sense. Various changes and modifications will become apparent to those of ordinary skill in the art. All such changes and modifications are seen to fall within the scope of the appended claims.

Claims

1. A sewing machine which forms stitches on a first object to be sewn based on stitch data, comprising:

an imaging unit which images an outline of an upper cloth as the first object onto a lower cloth as a second object, thereby obtaining image data;

an outline calculation unit which calculates the outline of the upper cloth from the image data obtained by the imaging unit;

a determination unit which determines a stitch-forming region for sewing the upper cloth onto the lower cloth based on the outline of the upper cloth calculated by the outline calculation unit; and

a stitch data generating unit which generates stitch data for the stitch-forming region determined by the determination unit.

2. The machine according to claim 1, wherein the upper cloth is a pocket cloth and the determination unit determines a region of the outline of the pocket cloth other than a region defining a pocket opening, as the stitch-forming region out of the outline of the pocket cloth, and the stitch data generating unit generates the stitch data according to the outline of the pocket cloth in the stitch generating region determined by the determination unit.

3. The machine according to claim 2, wherein the stitch data generating unit includes a reinforcement stitch data generating unit which generates reinforcement stitch data for forming reinforcement stitches on ends of the region defining the pocket opening.

4. The machine according to claim 3, further comprising a storage unit which stores a plurality of types of patterns as the reinforcement stitch data, wherein the reinforcement stitch data generating unit includes a setting unit which sets one of the types of patterns stored on the storage unit, said one type of pattern being desired by the user.

5. A stitch data generating device which generates stitch data for a sewing machine which forms stitches on a first object to be sewn based on stitch data, the device comprising:

an imaging unit which images an outline of an upper cloth as the first object to be sewn onto a lower cloth serving as a second object, thereby obtaining image data;

an outline calculation unit which calculates the outline of the upper cloth from the image data obtained by the imaging unit;

a determination unit which determines a stitch-forming region for sewing the upper cloth onto the lower cloth based on the outline of the upper cloth calculated by the outline calculation unit; and

a stitch data generating unit which generates stitch data for the stitch-forming region determined by the determination unit.

6. The device according to claim 5, wherein the upper cloth is a pocket cloth and the determination unit determines a region of the outline of the pocket cloth other than a region of a pocket opening as the stitch-forming region out of the outline of the pocket cloth, and the stitch data generating unit generates the stitch data along the outline of the pocket cloth in the stitch generating region determined by the determination unit.

7. The device according to claim 6, wherein the stitch data generating unit includes a reinforcement stitch data generating unit which generates reinforcement stitch data for forming a reinforcement stitch on ends of the region defining the pocket opening.

8. The device according to claim 7, further comprising a storage unit which stores a plurality of types of patterns as the reinforcement stitch data, wherein the reinforcement stitch data generating unit includes a setting unit which sets one of the types of patterns stored on the storage unit, said one type of pattern being desired by the user.

9. A computer-readable medium storing a stitch data generating program on which a computer executes processing for generating stitch data for a sewing machine which forms stitches on a first object to be sewn based on stitch data, the program comprising:

an imaging routine of imaging, by an imaging unit, an outline of an upper cloth as the first object to be sewn onto a lower cloth as a second object, thereby obtaining image data;

a calculation routine of calculating the outline of the upper cloth from the image data obtained by the imaging unit;

a determination routine for determining a stitch-forming region for sewing the upper cloth onto the lower cloth based on the outline of the upper cloth calculated by the outline calculation unit; and

a stitch data generating routine for generating stitch data for the stitch-forming region determined by the determination unit.