Title:
Sewing machine and computer-readable medium storing sewing machine control program
Kind Code:
A1


Abstract:
A sewing machine includes a sewing device, an imaging device, a determination device, a sewing condition storage device, a reading device, and a control device. The sewing device includes a needle bar and a sewing machine motor. The imaging device captures an image of a work cloth on which a marker is disposed to identify information corresponding to actual sewing conditions. The determination device determines an appearance feature of the work cloth based on the image obtained by the imaging device. The sewing condition storage device stores the appearance feature and sewing condition information corresponding to the sewing conditions that are correlated with each other. The reading device reads the sewing condition information corresponding to the appearance feature from the sewing condition storage device. The control device identifies the actual sewing conditions based on the sewing condition information read out by the reading device, and controls the sewing device.



Inventors:
Suzuki, Hiroyuki (Nagoya-shi, JP)
Taguchi, Shoichi (Toyohashi-shi, JP)
Iwata, Masayuki (Gifu-shi, JP)
Kawase, Kei (Nagoya-shi, JP)
Sugiura, Yoshio (Nishikamo-gun, JP)
Kishi, Motoshi (Nagoya-shi, JP)
Application Number:
12/379414
Publication Date:
10/29/2009
Filing Date:
02/20/2009
Assignee:
BROTHER KOGYO KABUSHIKI KAISHA (Nagoya-shi, JP)
Primary Class:
Other Classes:
112/470.01, 112/102.5
International Classes:
D05B19/14; D05B19/02; D05B19/16
View Patent Images:
Related US Applications:



Primary Examiner:
DURHAM, NATHAN E
Attorney, Agent or Firm:
OLIFF PLC (ALEXANDRIA, VA, US)
Claims:
What is claimed is:

1. A sewing machine that performs sewing on a work cloth, the sewing machine comprising: a sewing device that includes: a needle bar to which a sewing needle is to be attached; and a sewing machine motor that drives a needle bar mechanism via a drive shaft, the needle bar mechanism being configured to move the needle bar in an up-and-down direction; an imaging device that captures an image of the work cloth on which a marker is disposed to identify information corresponding to actual sewing conditions, the actual sewing conditions being sewing conditions to be used in actual sewing; a determination device that determines an appearance feature of the work cloth on which the marker is disposed, based on the image obtained by the imaging device; a sewing condition storage device that stores the appearance feature and sewing condition information corresponding to the sewing conditions that are correlated with each other; a reading device that reads out the sewing condition information corresponding to the appearance feature determined by the determination device from the sewing condition storage device; and a control device that identifies the actual sewing conditions based on the sewing condition information read by the reading device, and controls the sewing device so as to perform sewing.

2. The sewing machine according to claim 1, wherein the determination device determines at least one of a shape of the marker, a color of the marker, and a density of the marker, as the appearance feature.

3. The sewing machine according to claim 1, further comprising: a needle bar swinging motor that drives a needle bar swinging mechanism configured to swing the needle bar in a right-and-left direction with respect to a cloth feeding direction; and a feed adjustment motor that adjusts a feed amount by a cloth feed mechanism configured to feed the work cloth placed on a sewing machine bed, wherein: the sewing condition information includes at least one of sewing speed data about a rotation speed of the drive shaft, swing amount data about a movement amount in the right-and-left direction of the sewing needle by the needle bar swinging mechanism, and feed amount data about the feed amount by the cloth feed mechanism, and the control device controls at least one of the sewing machine motor, the needle bar swinging motor, and the feed adjustment motor.

4. The sewing machine according to claim 1, wherein the marker is a pin that has a head portion and a needle portion.

5. The sewing machine according to claim 1, wherein the marker is a sticker that has an adhesive layer on a surface.

6. A computer-readable medium storing a computer-executable sewing machine control program for a sewing machine to perform sewing on a work cloth, the sewing machine comprising a sewing device that includes a needle bar to which a sewing needle is to be attached and a sewing machine motor that drives via a drive shaft a needle bar mechanism configured to move the needle bar in an up-and-down direction, and the sewing machine control program comprising instructions for: determining an appearance feature of the work cloth on which a marker is disposed, based on an image obtained by image capturing of the work cloth on which the marker is disposed to identify information corresponding to actual sewing conditions, the actual sewing conditions being sewing conditions to be used in actual sewing; identifying sewing condition information that corresponds to the determined appearance feature based on a predetermined correlation between the appearance feature and the sewing condition information corresponding to the sewing conditions; and controlling the sewing device so as to perform sewing, based on the actual sewing conditions indicated by the identified sewing condition information.

7. The computer-readable medium according to claim 6, wherein determining an appearance feature of the work cloth includes determining at least one of a shape of the marker, a color of the marker, and a density of the marker as the appearance feature.

8. The computer-readable medium according to claim 6, wherein: the sewing machine further comprises: a needle bar swinging motor that drives a needle bar swinging mechanism configured to swing the needle bar in a right-and-left direction with respect to a cloth feeding direction; and a feed adjustment motor that adjusts a feed amount by a cloth feed mechanism configured to feed the work cloth placed on a sewing machine bed; the sewing condition information includes at least one of sewing speed data about a rotation speed of the drive shaft, swing amount data about a movement amount in the right-and-left direction of the sewing needle by the needle bar swinging mechanism, and feed amount data about the feed amount by the cloth feed mechanism; and controlling the sewing device includes controlling at least one of the sewing machine motor, the needle bar swinging motor, and the feed adjustment motor.

Description:

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to Japanese Patent Application No. 2008-045439, filed Feb. 27, 2008, the disclosure of which is hereby incorporated herein by reference in its entirety.

BACKGROUND

The present disclosure relates to a sewing machine and a computer-readable medium storing a sewing machine control program. More specifically, the present disclosure relates to a sewing machine that performs sewing based on a marker disposed on a work cloth and a computer-readable medium storing a sewing machine control program.

Conventionally, when sewing a work cloth (a sewing target) with a sewing machine, an operator (sewing machine user) may usually mark sewing positions on the work cloth with a chalk pencil, basting thread, pin, etc. and then perform sewing following the marks. In such a case, the operator may need to change sewing conditions (sewing speed, sewing method, for example) during sewing, while the operator moves the work cloth following the marks put on the work cloth as a guide. Therefore, to sew a complicated pattern, the sewing machine user may need to be experienced in operations of the sewing machine.

To solve the problem, for example, a sewing machine disclosed in Japanese Patent Application Laid-Open Publication No. 2007-289653 may capture an image of a baseline drawn on a work cloth, detect a baseline width and a baseline color, and specify a stitch width and a thread color that respectively correspond to the baseline width and baseline color, thereby automatically sewing a variety of stitch patterns along the baseline.

SUMMARY

With the conventional sewing machine described above, the operator may need to erase the baseline drawn on the work cloth after the operator has finished sewing.

Various exemplary embodiments of the general principles herein provide a sewing machine that is capable of setting sewing conditions and eliminates the need for a change in the set sewing conditions during sewing and the need for extra work after sewing, and a computer-readable medium storing a sewing machine control program.

Exemplary embodiments provide a sewing machine that performs sewing on a work cloth and includes a sewing device, an imaging device, a determination device, a sewing condition storage device, a reading device, and a control device. The sewing device includes a needle bar to which a sewing needle is to be attached, and a sewing machine motor that drives a needle bar mechanism configured to move the needle bar in an up-and-down direction via a drive shaft. The imaging device captures an image of the work cloth on which a marker is disposed to identify information corresponding to actual sewing conditions to be used in actual sewing. The determination device determines an appearance feature of the work cloth on which the marker is disposed, based on the image obtained as a result of image capturing by the imaging device. The sewing condition storage device stores the appearance feature and sewing condition information about the sewing conditions that are correlated with each other. The reading device reads out the sewing condition information corresponding to the appearance feature determined by the determination device from the sewing condition storage device. Further, the control device identifies the actual sewing conditions based on the sewing condition information read out by the reading device, and controls the sewing device so as to perform sewing.

Exemplary embodiments also provide a computer-readable medium storing a sewing machine control program for a sewing machine to perform sewing on a work cloth. The sewing machine includes a sewing device that includes a needle bar to which a sewing needle is to be attached and a sewing machine motor that drives via a drive shaft a needle bar mechanism configured to move the needle bar in an up-and-down direction. The sewing machine control program causing a controller of the sewing machine to execute instructions of determining an appearance feature of the work cloth on which a marker is disposed, based on an image obtained by image capturing of the work cloth on which the marker is disposed to identify information corresponding to actual sewing conditions, the actual sewing conditions being sewing conditions to be used in actual sewing, identifying sewing condition information that corresponds to the determined appearance feature based on a predetermined correlation between the appearance feature and the sewing condition information about the sewing conditions, and controlling the sewing device so as to perform sewing, based on the actual sewing conditions indicated by the identified sewing condition information.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments of the present disclosure will be described below in detail with reference to the accompanying drawings in which:

FIG. 1 is a perspective view of a sewing machine;

FIG. 2 is an enlarged view of a head;

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

FIG. 4 is a schematic diagram of storage areas arranged in an ROM;

FIG. 5 is a schematic diagram of a sewing condition storage area in a first embodiment;

FIG. 6 is an external view of a pin in the first embodiment;

FIG. 7 is an illustration of a work cloth to which pins are fixed;

FIG. 8 is a main flowchart of sewing control processing;

FIG. 9 is a subroutine flowchart of sewing conditions specification processing;

FIG. 10 is an illustration of a pattern sewn on the work cloth in the first embodiment;

FIG. 11 is a schematic diagram of the sewing condition storage area in a second embodiment;

FIG. 12 is an illustration of pins disposed on the work cloth in the second embodiment;

FIG. 13 is a schematic diagram of the sewing condition storage area in a third embodiment;

FIG. 14 is an illustration of pins disposed on the work cloth in the third embodiment; and

FIG. 15 is an illustration of a sticker put on a work cloth 60.

DETAILED DESCRIPTION OF EMBODIMENTS

The following will describe a sewing machine 1 according to a first embodiment of the present disclosure with reference to the drawings. The drawings will be used to explain technological features that may be employed in the present disclosure, and configurations of an apparatus and flowcharts of a variety of processing are provided for just illustrative purposes and not intended to be restrictive.

The physical configuration of a sewing machine 1 according to the present embodiment will be described below with reference to FIGS. 1 and 2. As shown in FIG. 1, the sewing machine 1 includes a bed portion 2, a pillar 3 erected upward from the bed portion 2 at the right end of the bed portion 2, an arm portion 4 extending leftwards from the upper end of the pillar 3 in parallel with the bed portion 2, and a head 41 provided at the end of the arm portion 4. The side, which the operator of the sewing machine 1 faces for sewing, is referred to as the “front side” of the sewing machine 1, and the opposite side thereof is referred to as the “rear side” of the sewing machine 1. The side at which the pillar 3 is disposed is referred to as the “right side” and the opposite side thereof is referred to as the “left side” of the sewing machine 1.

The bed portion 2 is provided with a needle plate 11 and a needle plate cover 12 that can be opened and closed. In the needle plate 11, square holes 34 are formed. Feed dogs (not shown), which will be described later, may be raised and lowered through the square holes 34. In the bed portion 2 below the needle plate 11, a shuttle mechanism (not shown) that houses a bobbin for a lower thread (not shown) is provided. The shuttle mechanism is configured in such a manner that the bobbin can be attached to and detached from the shuttle mechanism when the needle plate cover 12 is detached. Below the needle plate 11, the bed portion 2 contains the feed dogs (not shown) to feed a work cloth as a sewing target by a certain feed amount, a cloth feed mechanism (not shown) to drive the feed dogs, and a feed adjustment motor 76 (see FIG. 3) to adjust the feed amount. At the lower part in the pillar 3, a sewing machine motor 77 (see FIG. 3) is provided. Drive power of the sewing machine motor 77 will be transmitted via a drive belt (not shown) to a drive shaft (not shown) that extends in the right-and-left direction in the arm portion 4. The drive power of the sewing machine motor 77 will be transmitted also to a lower shaft (not shown) that extends in the right-and-left direction in the bed portion 2, via a transmission mechanism (not shown) provided at a part of the sewing machine drive shaft. With such a configuration, a needle bar 8, a thread take-up mechanism (not shown), the shuttle mechanism (not shown), the cloth feed mechanism, etc. may be synchronously driven.

As shown in FIG. 1, the pillar 3 is provided with a vertically long liquid crystal display (LCD) 10. The LCD 10 displays names of a variety of functions that may be required to perform sewing operations, as well as a variety of messages. The variety of functions may include pattern setting and editing, for example. On the front surface of the LCD 10, a touch panel 111 (see FIG. 3) is mounted. If any one of items displayed on the LCD 10 is selected with a finger or a dedicated pen, the item may be sensed on the touch panel 111. The operator may thus enter various instructions via the LCD 10. On the right side surface of the pillar 3, a connector 108 (see FIG. 3) is provided. Via the connector 108, various kinds of data and programs can be input to and output from the sewing machine 1.

Over the top of the arm portion 4, a cover 6 is mounted to cover the entire length of the arm portion 4 in the right-and-left direction. The cover 6 is pivotally supported on the rear upper surface of the arm portion 4 so that the cover 6 may be opened and closed around the longitudinal axis along the arm portion 4. As shown in FIG. 1, under the cover 6, near the midsection on the upper surface of the arm portion 4, a thread spool housing 15 is provided as a concave portion. The spool housing 15 is configured to house a thread spool 21 with a needle thread wound around. From the right side surface of the thread spool housing 15, a thread spool pin 17 to support the thread spool 21 extends in parallel with the arm portion 4. At the lower part of the head 41, a needle bar 8 is disposed. A sewing needle 16 (see FIG. 2) may be attached to the needle bar 8. The head 41 contains a needle bar mechanism (not shown), a needle bar swinging motor 78, and the thread take-up mechanism (not shown). The needle bar mechanism is configured to move up and down the needle bar 8 with the sewing needle 16. The needle bar swinging motor 78 (see FIG. 3) is used to swing the needle bar 8 right and left. At the rear side of the needle bar 8, a presser bar 14 (see FIG. 2) is provided. The presser bar 14 has a presser foot 13 (see FIG. 2) at a lower end to hold a work cloth. The arm portion 4 has a thread guide groove 7 which guides a needle thread pulled out from the thread spool 21 to the sewing needle 16 via a tension mechanism (not shown), a thread take-up spring (not shown), and a thread take-up lever, etc. (not shown).

A plurality of operation keys 9 are provided on the front surface of the arm portion 4. The operation keys 9 may be used for instructing various sewing operations. The operation keys 9 may include a start-and-stop switch 91, a reverse stitch switch 92, a needle up-and-down switch 93, and a speed control lever 94. The start-and-stop switch 91 may be used to start or stop sewing operations. The reverse stitch switch 92 may be used to perform reverse stitching. The needle up-and-down switch 93 is used to switch a position of the sewing needle 16 between upper and lower positions. The speed control lever 94 is used to set a sewing speed.

Further, as shown in FIG. 2, in the head 41, on the front side of the needle bar 8 and somewhat to the right of the needle bar 8 in front view, an image sensor 30 is mounted so that the image sensor 30 can capture an image of an area including a needle drop hole 131 formed in the presser foot 13 and its vicinity. The needle drop hole 131 has a size large enough for the sewing needle 16 to pass through. The image sensor 30 may include, for example, a CMOS sensor and a control circuit, and the CMOS sensor will capture an image. In the present embodiment, as shown in FIG. 2, a support frame 31 is attached to a frame (not shown) of the sewing machine 1, and the image sensor 30 is fixed to the support frame 31.

Next, the electrical configuration of the sewing machine 1 will be described below with reference to FIG. 3. As shown in FIG. 3, the control system of the sewing machine 1 has a configuration centered on a control portion 100. The control portion 100 includes a CPU 101, a ROM 102, a RAM 103, an EEPROM 104, an external access RAM 105, an input interface (I/F) 106, an output I/F 107, all of which are connected to each other with a bus 110. The sewing start-and-stop switch 91, the reverse stitch switch 92, the needle up-and-down switch 93, and the speed control lever 94 (see FIG. 1 for all of them), the touch panel 111, and the image sensor 30 (see FIG. 2) are respectively connected to the input I/F 106. Drive circuits 71, 72, 73, and 74 to respectively drive the feed adjustment motor 76, the sewing machine motor 77, the needle bar swinging motor 78, and the LCD 10 (see FIG. 1) are connected to the output I/F 107. A connector 108 is connected to the external access RAM 105. Information stored in the external access RAM 105 can be output to the outside of the sewing machine 1 via the external access RAM 105.

The CPU 101 in the control portion 100 conducts main control over the sewing machine 1 and executes computations and processing in accordance with a variety of programs stored in a control program storage area 201 (see FIG. 4) in the ROM 102, which is a read-only memory. The RAM 103, which is a random access memory, has storage areas to store various kinds of data temporarily.

Next, the storage areas arranged in the ROM 102 will be described below with reference to FIG. 4. As shown in FIG. 4, the ROM 102 may have the control program storage area 201, an initial setting information storage area 202, a sewing condition storage area 203, a possible sewing condition storage area 204, and other storage areas.

The control program storage area 201 may store a control program required by the CPU 101 (see FIG. 3) to execute sewing control processing (see FIGS. 8 and 9) including appearance feature recognition processing for a head portion 51 of a pin 50 (see FIG. 6). The pin 50 will be described in detail later. The initial setting information storage area 202 may store initial setting information that will be read out when the CPU 101 is powered or reset. An example of the initial setting information may include initial values of sewing condition information (described later) about the sewing conditions.

The sewing condition storage area 203 may store sewing condition information in association with each of a plurality of different shapes, in plane view, of the head portion 51 of the pin 50. The sewing conditions may include, for example, a sewing pattern, a swing amount, a feed amount, and a sewing speed. The sewing conditions will be described in detail later with reference to FIG. 5. In accordance with a planar shape of the head portion 51 of the pin 50, the CPU 101 selects and reads out any one of a plurality of the sewing condition information pieces stored in the sewing condition storage area 203 and stores the information in an actual condition storage area (not shown) of the RAM 103. The actual condition storage area will be described later. Based on the stored sewing condition information, the CPU 101 controls the drive circuits 71 to 73 (see FIG. 3) to respectively drive the feed adjustment motor 76 (see FIG. 3), the sewing machine motor 77 (see FIG. 3), and the needle bar swinging motor 78 (see FIG. 3).

The possible sewing condition storage area 204 may store specifications of the sewing machine 1, that is, limit values of the swing amount, the feed amount, and the sewing speed of the sewing machine 1, for example. If any one of the swing amount, the feed amount, and the sewing speed read out from the sewing condition storage area 203 as the sewing conditions, in accordance with the planar shape of the head portion of the pin 50, exceeds the corresponding limit value stored in the possible sewing condition storage area 204, the CPU 101 determines that the sewing conditions do not comply with the specifications of the sewing machine 1.

Next, the storage areas arranged in the RAM 103 will be described below. Although not shown, the RAM 103 may be provided with the actual condition storage area and other storage areas. The actual condition storage area stores sewing condition information, that is, information about the sewing pattern, the swing amount, the feed amount, and the sewing speed for currently executed sewing processing. The CPU 101 (see FIG. 3) may refer to the swing amount included in the sewing condition information stored in the actual condition storage area. The CPU 101 may then calculate a drive amount of the needle bar swinging motor 78 (see FIG. 3) corresponding to the stored swing amount, and control the drive circuit 73 (see FIG. 3) based on the calculated drive amount. The CPU 101 may also refer to the feed amount included in the stored sewing condition information. The CPU 101 may then calculate a drive amount of the feed adjustment motor 76 (see FIG. 3) so that the actual feed amount by the feed dogs driven by the feed mechanism equals to the stored feed amount, and control the drive circuit 71 based on the calculated drive amount. Similarly, based on the sewing speed included in the stored sewing condition information, the CPU 101 may calculate a rotation speed of the sewing machine motor 77. Specifically, the CPU 101 may calculate the rotation speed so that a rotation speed of the drive shaft equals to the sewing speed, and control the drive circuit 72 to realize the calculated rotation speed.

The sewing condition information stored in the sewing condition storage area 203 of the ROM 102 will be described in detail with reference to FIG. 5. In the first embodiment, the CPU 101 identifies sewing conditions by recognizing the planar shape of the head portion 51 of the pin 50 (see FIG. 6) as an appearance feature. For this purpose, in the sewing condition storage area 203, the sewing conditions (a sewing pattern, a swing amount, a feed amount, and a sewing speed) to be used for sewing are stored beforehand for each of the planar shapes of the head portion 51. Specifically, as shown in FIG. 5, as the sewing conditions, a sewing pattern 301, a swing amount 302, a cloth feed amount 303, and a sewing speed 304 are stored beforehand for each of the planar shapes of the head portion 51. Because the shapes of the head portion 51 of the pin 50 are correlated with the sewing conditions beforehand, it may be easy for the operator to visually recognize the sewing conditions when the pin 50 is disposed on the work cloth.

For example, in an example shown in FIG. 5, corresponding to the planar shape of the head portion 51 of the pin 50 “circle”, the sewing pattern 301 “straight stitch”, swing amount 302 “0 mm”, feed amount 303 “2.5 mm”, and sewing speed 304 “low speed (70 rpm)” are stored. Corresponding to the planar shape “heart”, the sewing pattern 301 “straight stitch”, swing amount 302 “0 mm”, feed amount 303 “2.5 mm”, and sewing speed 304 “high speed (750 rpm)” are stored. Corresponding to the planar shape “triangle”, the sewing pattern 301 “zigzag stitch”, swing amount 302 “2.0 mm”, feed amount 303 “1.4 mm”, and sewing speed 304 “medium speed (410 rpm)” are stored. Corresponding to the planar shape “square”, the sewing pattern 301 “zigzag stitch”, swing amount 302 “3.5 mm”, feed amount 303 “1.4 mm”, and sewing speed 304 “high speed (750 rpm)” are stored. Corresponding to the planar shape “star”, the sewing pattern 301 “blind stitch”, swing amount 302 “0 mm”, feed amount 303 “2.0 mm”, and sewing speed 304 “low speed (70 rpm)” are stored. Corresponding to the planar shape “character X”, the sewing pattern “STOP” to stop sewing control processing is stored.

In the first embodiment, the CPU 101 (see FIG. 3) in the sewing machine 1 (see FIG. 1) causes the image sensor 30 (see FIG. 2) to capture an image of the head portion 51 of the pin 50 stuck through the work cloth, and recognizes the shape. Then, the CPU 101 identifies sewing conditions that correspond to the recognized shape by referencing the sewing condition storage area 203.

Next, an example of the pin 50 that may be used in the present embodiment will be described below with reference to FIG. 6. As shown in FIG. 6, the pin 50 has the head portion 51 and a needle portion 52. The needle portion 52 is connected to the head portion 51 and has a pointed tip. The needle portion 52 may be stuck through the work cloth to be fixed. The head portion 51 may be a plate-like portion made of plastic, for example. The head portion 51 is connected to the end opposite to the pointed tip of the needle portion 52. An example of FIG. 6 shows the pin 50 whose head portion 51 is shaped as a circle in plan view. In the first embodiment, a plurality of the pins 50 having the head portions 51 with different planar shapes may be stuck through the work cloth to be fixed.

Next, how the pins 501 to 504 are fixed on a pair of work cloths 60 will be described below with reference to FIG. 7. In FIG. 7, a sewing path intended by the operator is indicated by a dash-and-dot line 61.

The work cloths 60 may be fed from the front side to the rear side. Therefore, FIG. 7 shows a situation that the operator intends to sew up the work cloths 60 from the rear side to the front side along the dash-and-dot straight line 61 along the right edge of the work cloths 60. In such a case, the pins 501 to 504 may be stuck through the work cloths 60 and fixed in a condition where the respective needle portions 521 to 524 intersect with the dash-and-dot line 61 orthogonally and the tips of the respective needle portions 521 to 524 are pointed to the left side from the right edge side of the work cloths 60. On the right side of the dash-and-dot line 61, the head portions 511 to 514 of the respective pins 501 to 504 are disposed. By thus disposing the pins 501 to 504, as the work cloths 60 are fed by the feed dog, the head portions 511 to 514 of the respective pins 501 to 504 may be moved sequentially through the right side of the presser foot 13. The right side portion of the presser foot 13 is an imaging area where the image sensor 30 (see FIG. 2) can capture an image. The sewing machine 1 (see FIG. 1) may capture images of the shapes of the head portions 511 to 514 of the respective pins 501 to 504, and performs sewing.

In the example shown in FIG. 7, from the rear side to the front side, the total of four pins 501 to 504 are stuck through the work cloths 60 and fixed in sequence. Specifically, from the top in FIG. 7, the pin 501 having the “star” shape, the pin 502 having the “triangle” shape, the pin 503 having the “circle” shape, and the pin 504 having the “character X” shape are sequentially disposed. In such a manner, the needle portions 521 to 524 of the respective pins 501 to 504 may secure the work cloths 60, and the pins 501 to 504 may identify a start position and an end position of sewing in a specific sewing method.

Subsequently, the sewing control processing that is executed by the CPU 101 (see FIG. 3) of the sewing machine 1 will be described below with reference to FIGS. 8 and 9. A program that causes the CPU 101 to execute processing shown in FIGS. 8 and 9 is stored in the control program storage area 201 (see FIG. 4) of the ROM 102.

First, a main flowchart of the sewing control processing will be described below with reference to FIG. 8. The main flowchart of FIG. 8 starts if the power of the sewing machine 1 is turned on by the operator.

As shown in FIG. 8, following the start of the processing, initialization processing of the sewing machine 1 is executed. In the initialization processing, the CPU 101 reads out the initial setting information from the initial setting information storage area 202 of the ROM 102 (S11). Among the read out initial setting information, the initial setting values for the sewing conditions (a sewing pattern, a swing amount, a feed amount, and a sewing speed) are stored in the actual condition storage area of the RAM 103. In this state, if various kinds of setting information are inputted via the touch panel 111 of the LCD 10, the speed control lever 94, etc., the inputted setting information is stored in the actual condition storage area as the sewing condition information (S11). Based on the sewing condition information stored in the actual condition storage area, the CPU 101 executes the sewing control processing. Therefore, if nothing is changed hereafter, the sewing pattern, the swing amount, the feed amount, and the sewing speed that are stored in the actual condition storage area at this point may be used as the sewing conditions in the sewing control processing to be executed. The sewing pattern, the swing amount, the feed amount, and the sewing speed that are stored in the actual condition storage area will be hereinafter referred to as “actual sewing conditions”.

Subsequently, the CPU 101 determines whether an instruction to start sewing is given, based on whether the start-and-stop switch 91 is pressed once by the operator (S13). The CPU 101 waits until the instruction to start sewing is given (NO at S13→S13). If the instruction is given (YES at S13), the CPU 101 determines whether an instruction to end sewing is given (S14). If the start-and-stop switch 91 is pressed again, the CPU 101 determines that the instruction to end sewing is given (YES at S14). Then, the CPU 101 stops the currently executed sewing processing (S12), and returns to the processing to acquire the setting information (S11).

If the start-and-stop switch 91 is not pressed again (NO at S14), an image of the work cloth 60 and the head portion 51 of the pin 50 placed in the imaging area of the image sensor 30 is captured to obtain image information. The obtained image information is subjected to image processing, and processing to recognize an appearance feature of the head portion 51 of the pin 50 (hereinafter referred to as “appearance feature recognition processing”) is performed (S15). In the appearance feature recognition processing, the appearance feature of the work cloth with the pin 50 disposed thereon may be recognized, based on the image information obtained from the image sensor 30. In the first embodiment, as an example of the appearance feature recognition processing, processing to recognize the shape of the head portion 51 (hereinafter referred to as “shape recognition processing”) is executed.

The shape recognition processing may be executed as follows, for example. First, binarization processing may be performed to binarize the image information obtained by image capturing to extract position information of the head portion 51 of the pin 50, which has higher brightness with respect to the brightness of the work cloth. The threshold value of the brightness may be determined by a p-tile method, a mode method, a discrimination analysis method, a variable threshold method, etc. Subsequently, edge detection may be performed to identify a boundary (edge) between light and dark in the image information to extract position information of the boundary line between the head portion 51 of the pin 50 and the work cloth 60. A filter to be used in edge detection may include a first derivative filter, a Laplacian filter, etc. Subsequently, through Hough transform, an edge that forms a curve or a straight line may be extracted to identify a shape of the head portion 51 of the pin 50. By determining whether the acquired shape is the same as a predetermined shape, the shape of the head portion 51 of the pin 50 may be identified.

Further, in the image processing, from among all the image information pieces of the imaging area captured by the image sensor 30, the image information of a certain area at the right side of the presser foot 13 (hereinafter referred to as a target area) is selected, and the shape recognition processing is executed for the target area. Thus, when the head portion 51 of the pin 50 passes by the right side of the needle drop hole 131 in the presser foot 13, the shape of the head portion 51 may be recognized. Accordingly, at this timing, the sewing conditions may be changed (see S23 in FIG. 9).

If the CPU 101 cannot identify the shape of the head portion 51 of the pin 50 through the shape recognition processing (NO at S17), the CPU 101 determines that the head portion 51 of the pin 50 is not present in the target area of the image sensor 30. Then, sewing is executed based on the actual sewing conditions stored in the actual condition storage area of the RAM 103 (S19). The process returns to step S14, and the processing to monitor an instruction from the start-and-stop switch 91 (S14), the processing to detect the head portion 51 of the pin 50, and the shape recognition processing (S15) are executed repeatedly.

If the shape of the head portion 51 of the pin 50 is identified through the shape recognition processing (YES at S17), the CPU 101 reads out the sewing conditions identified by the planar shape of the head portion 51 of the pin 50, from the sewing condition storage area 203 of the ROM 102 (S18). The CPU 101 stores the read out sewing information in a storage area arranged in the RAM 103. Subsequently, the CPU 101 determines whether the identified shape of the head portion 51 of the pin 50 is the “character X”, that is, whether the identified shape is a sewing pattern that indicates stop of sewing (S21). If the shape of the head portion 51 of the pin 50 is the “character X”, the sewing pattern stored in the actual condition storage area of the RAM 103 is “STOP”, so that it is necessary to end the continuing sewing control processing. Therefore, in such a case (YES at S21), the CPU 101 stops sewing (S27), ends a series of the sewing control processing, and returns to the setting information acquisition processing (S11) again to perform new sewing.

If the shape of the head portion 51 of the pin 50 identified by the CPU 101 is any other than the “character X”, that is, if the identified shape is not the sewing pattern that indicates stop of sewing (NO at S21), the CPU 101 proceeds to sewing condition identification processing (see S23 in FIG. 9). In the sewing condition identification processing, the CPU 101 determines the actual sewing conditions based on the sewing conditions that correspond to the planar shape of the head portion 51 of the pin 50, and executes the sewing processing.

The sewing condition identification processing to be executed at step S23 of the sewing control processing will be described below with reference to FIG. 9. In the sewing condition identification processing, as shown in FIG. 9, the CPU 101 determines whether the sewing conditions that have been read out according to the recognized shape of the head portion 51 of the pin 50 comply with the specifications of the sewing machine 1 (S31). Specifically, the CPU 101 compares the swing amount, the feed amount, and the sewing speed included in the read out sewing conditions with the respective limit values of the swing amount, the feed amount, and the sewing speed stored in the possible sewing condition storage area 204 of the ROM 102. If at least any one of the swing amount, the feed amount, and the sewing speed read out according to the recognized shape of the head portion 51 is found to exceed the limit value, the CPU 101 determines that the sewing conditions do not comply with the specifications of the sewing machine 1 (NO at S31).

In such a case, the sewing machine 1 cannot perform sewing based on the sewing conditions identified by the head portion 51 of the pin 50. Accordingly, the CPU 101 causes the LCD 10 to display an error message saying, for example, “THIS SEWING MACHINE CANNOT PERFORM SEWING”, to inform the operator that sewing cannot be continued (S47). The CPU 101 stores 1 to turn a stop flag “ON”, which indicates stop of sewing (S49), ends the sewing condition identification processing, and returns to the sewing control processing (see FIG. 8).

If the sewing conditions that are read out in accordance with the recognized planar shape of the head portion 51 of the pin 50 comply with the specifications of the sewing machine 1, the CPU 101 determines that sewing can be performed with the sewing machine 1 (YES at S31). In such a case, the CPU 101 compares the actual sewing conditions stored in the actual condition storage area of the RAM 103 with the newly identified sewing conditions to determining whether the both sewing conditions are identical (S33, S37, and S41).

More specifically, first, among the sewing conditions, the CPU 101 determines whether the sewing speeds are identical with each other (S33). The CPU 101 refers to the sewing condition storage area 203 of the ROM 102. If the CPU 101 determines that the sewing speed identified by the planar shape of the head portion 51 of the pin 50 is identical to the sewing speed in the actual sewing conditions (YES at S33), proceeds to step S37 without changing the sewing speed of the actual sewing conditions. If the CPU 101 determines that the sewing speed identified by the planar shape of the head portion 51 of the pin 50 is not identical to the sewing speed in the actual sewing conditions (NO at S33), the sewing speed identified by the planar shape overwrites the sewing speed stored in the actual condition storage area (S35). Furthermore, a rotation speed of the sewing machine motor 77 is calculated and set such that the rotation speed of the drive shaft of the sewing machine 1 may be equal to the identified sewing speed. Then, the process proceeds to S37.

At step S37, among the sewing conditions, the CPU 101 determines whether the swing amounts are identical (S37). The CPU 101 refers to the sewing condition storage area 203 of the ROM 102. If the CPU 101 determines that the swing amount identified by the planar shape of the head portion 51 of the pin 50 is identical to the swing amount in the actual sewing conditions (YES at S37), proceeds to step S41 without changing the swing amount of the actual sewing conditions. If the CPU 101 determines that the swing amount identified by the planar shape of the head portion 51 of the pin 50 is not identical to the swing amount in the actual sewing conditions (NO at S37), the swing amount identified by the planar shape overwrites the swing amount stored in the actual condition storage area (S39). Furthermore, a drive amount of the needle bar swinging motor 78 is calculated and set such that a swing amount of the needle bar 8 caused by the needle bar swinging mechanism may be equal to the identified swing amount. Then, the process proceeds to step S41.

At step S41, among the sewing conditions, the CPU 101 determines whether the feed amounts are identical (S41). The CPU 101 refers to the sewing condition storage area 203 of the ROM 102. If the CPU 101 determines that the feed amount identified by the planar shape of the head portion 51 of the pin 50 is identical to the feed amount in the actual sewing conditions (YES at S41), proceeds to step S45 without changing the feed amount of the actual sewing conditions. If the CPU 101 determines that the feed amount identified by the planar shape of the head portion 51 of the pin 50 is not identical to the feed amount of the actual sewing condition (NO at S41), the feed amount identified by the planar shape overwrites the feed amount stored in the actual condition storage area (S43). Furthermore, a drive amount of the feed adjustment motor 76 is calculated and set such that the feed amount of the feed dogs caused by the cloth feed mechanism may be equal to the identified feed amount. Then, the process proceeds to step S45.

At step S45, based on the thus set drive amount of the feed adjustment motor 76, the rotation speed of the sewing machine motor 77, and the drive amount of the needle bar swinging motor 78, the CPU 101 controls the drive circuits 71 to 73 to drive the feed adjustment motor 76, the sewing machine motor 77, and the needle bar swinging motor 78, respectively, thereby performing sewing on the work cloth 60 (S45). After the sewing is performed, the sewing condition identification processing ends to return to the sewing control processing (see FIG. 8).

In the sewing control processing, as shown in FIG. 8, the CPU 101 determines whether the stop flag is ON (S25). If the stop flag is ON (YES at S25), the sewing conditions identified by the recognized head portion 51 of the pin 50 do not comply with the specification of the sewing machine 1. Therefore, the CPU 101 stops sewing processing (S27). Then the CPU 101 returns to the setting information acquisition processing (S11) again to perform new sewing. If the stop flag is OFF (NO at S25), the CPU 101 returns to step S14 to continue the sewing processing.

Next, a specific example of sewing procedures will be described below with reference to FIGS. 7 and 10, in a case where the sewing control processing is performed according to the flowcharts shown in FIGS. 8 and 9. FIG. 10 shows a sewing pattern sewn on the work cloth 60 in a case where the pins 50 are disposed as illustrated in FIG. 7. Prior to sewing with the sewing machine 1, the operator sticks the pins 501 to 504 through a work cloth 60 to be fixed in such a manner that respective head portions 511 to 514 of the pins 501 to 504 may be disposed at the right sides of desired positions to be sewn on the work cloth 60. In an example shown in FIG. 10, a total of four pins 501 to 504 are disposed. The respective head portions 511 to 514 of the pins 501 to 504 have the planar shapes of the “star” (head portion 511), the “triangle” (head portion 512), the “circle” (head portion 513), and the “character X” (head portion 514) in this order starting from the rear side of the sewing machine 1.

Sewing may be started at the upper end of the dash-and-dot line 61 shown in FIG. 7 (rear side of the sewing machine 1) (S11 and S13). If start of sewing is instructed (YES at S13), the image sensor 30 in the sewing machine 1 captures an image of the work cloth 60 in the imaging area (S15). In a condition shown in FIG. 7, the head portion 511 of the pin 501 may not be detected (NO at S17). Accordingly, sewing may be performed based on the actual sewing conditions, that is, the sewing pattern, the swing amount, the feed amount, and the sewing speed that have been read out from the initial setting information storage area 202 of the ROM 102 and stored into the actual condition storage area of the RAM 103 upon start-up of the sewing machine 1 (S19). In this case, it is assumed that sewing may be performed based on the initial sewing conditions of a sewing pattern of a straight stitch, a swing amount of 0 mm, a feed amount of 1.4 mm, and a sewing speed of a low speed (70 rpm).

Subsequently, the needle drop hole 131 in the presser foot 13 reaches to the left of an area where the pin 501 having the “star”-shaped head portion 511 is disposed. At this timing, an image of the head portion 511 of the pin 501 is captured by the image sensor 30 so that the shape may be recognized (S15). The sewing conditions corresponding to the shape “star” are read out from the sewing condition storage area 203 of the ROM 102 and identified (YES at S17→S18). Then, the actual sewing conditions stored in the actual sewing condition storage area of the RAM 103 are changed to a sewing pattern of blind stitch, a swing amount of 0 mm, a feed amount of 2.0 mm, and a sewing speed of a low speed (70 rpm) (S33 to S43). Based on the thus changed actual sewing conditions, sewing is performed (S45).

Subsequently, the needle drop hole 131 in the presser foot 13 reaches to the left of an area where the pin 502 having the “triangle”-shaped head portion 512 is disposed. At this timing, an image of the head portion 512 of the pin 502 is captured by the image sensor 30 so that the shape may be recognized (S15). The sewing conditions corresponding to the shape “triangle” are read out from the sewing condition storage area 203 of the ROM 102 and identified (YES at S17→S18). Then, the actual sewing conditions stored in the actual sewing condition storage area of the RAM 103 are changed to a sewing pattern of a zigzag stitch, a swing amount of 2.0 mm, a feed amount of 1.4 mm, and a sewing speed of a medium speed (410 rpm) (S33 to S43). Based on the thus changed actual sewing conditions, sewing is performed (S45).

Subsequently, the needle drop hole 131 in the presser foot 13 reaches to the left of an area where the pin 503 having the “circle”-shaped head portion 513 is disposed. At this timing, an image of the head portion 513 of the pin 503 is captured by the image sensor 30 so that the shape may be recognized (S15). The sewing conditions corresponding to the shape “circle” are read out from the sewing condition storage area 203 of the ROM 102 and identified (YES at S17→S18). Then, the actual sewing conditions stored in the actual sewing condition storage area of the RAM 103 are changed to a sewing pattern of a straight stitch, a swing amount of 0 mm, a feed amount of 2.5 mm, and a sewing speed of a low speed (70 rpm) (S33 to S43). Based on the thus changed actual sewing conditions, sewing is executed (S45).

Subsequently, the needle drop hole 131 in the presser foot 13 reaches to the left of an area where the pin 504 having the “character X”-shaped head portion 514 is disposed. At this timing, an image of the head portion 514 of the pin 504 is captured by the image sensor 30 so that the shape may be recognized (S15). The sewing conditions corresponding to the shape “character X” are read out from the sewing condition storage area 203 of the ROM 102 and identified (YES at S17→S18). Because the sewing pattern corresponding to the shape “character X” is “STOP” (YES at S21), sewing is stopped (S27). Sewing is performed in such a manner, and the patterns of “straight stitch”, “blind stitch”, “zigzag stitch”, and “straight stitch” are sewn in this order along the dash-and-dot line 61 on the work cloth 60, as shown in FIG. 10.

As described above, the pins 501 to 504 may be disposed on the work cloths 60 as a sewing target so that images of the respective head portions 511 to 514 of the pins 501 to 504 may be captured by the image sensor 30 provided in the sewing machine 1. From the image information obtained by image capturing, the shape of the head portion 51 may be recognized. Then, sewing may be performed based on the sewing conditions corresponding to the recognized shapes. Accordingly, the operator need not manually change the sewing conditions during sewing. Therefore, even if the operator is not skilled in sewing operations, the operator can sew a pattern based on a combination of complicated sewing conditions.

The following will describe a sewing machine 1 according to the second embodiment of the present disclosure with reference to the drawings. The second embodiment is almost the same as the first embodiment described above except for the contents of the appearance feature recognition processing (see S15 in FIG. 8). Therefore, the description of the same configurations and processing shown in FIGS. 1 to 4, 8, and 9 will be omitted below.

In contrast to the first embodiment, in the second embodiment, processing of recognizing a color of the head portion 51 of the pin 50 (hereinafter referred to as “color recognition processing”) may be performed. The color recognition processing is another example of the appearance feature recognition processing. For this purpose, the color of the head portion 51 of the pin 50 is correlated with the sewing conditions (the sewing pattern, the swing amount, the feed amount, and the sewing speed) and stored in the sewing condition storage area 203 of the ROM 102. When sewing is performed, an image of the head portion 51 of the pin 50 disposed on the work cloth may be captured by the image sensor 30 and the color may be determined. The sewing conditions that correspond to the color may be read out from the sewing condition storage area 203 of the ROM 102 and identified. Then, based on the identified sewing conditions, sewing may be performed.

The sewing conditions stored in the sewing condition storage area 203 of the ROM 102 will be described in detail below, with reference to FIG. 11. The sewing condition storage area 203 of the present embodiment stores the sewing conditions for each color of the head portion 51 of the pin 50. Specifically, as shown in FIG. 11, the stored sewing conditions may include a sewing pattern 401, a swing amount 402, a feed amount 403, and a sewing speed 404 for each color. Because the colors of the head portion 51 of the pin 50 are correlated with the sewing conditions beforehand, it may be easy for the operator to visually recognize the sewing conditions when the pin 50 is disposed on the work cloth.

In an example shown in FIG. 11, corresponding to the color of the head portion 51 of the pin 50 “blue”, the sewing pattern 401 “straight stitch”, the swing amount 402 “0 mm”, the feed amount 403 “1.4 mm”, and the sewing speed 404 “low speed (70 rpm)” are stored. Corresponding to the color “yellow”, the sewing pattern 401 “straight stitch”, the swing amount 402 “0 mm”, the feed amount 403 “1.4 mm”, and the sewing speed 404 “medium speed (410 rpm)” are stored. Corresponding to the color “white”, the sewing pattern 401 “straight stitch”, the swing amount 402 “0 mm”, the feed amount 403 “2.5 mm”, and the sewing speed 404 “high speed (750 rpm)” are stored. Corresponding to the color “green”, the sewing pattern 401 “zigzag stitch”, the swing amount 402 “2.0 mm”, the feed amount 403 “1.4 mm”, and the sewing speed 404 “low speed (70 rpm)” are stored.

Corresponding to the color of the head portion 51 “brown”, the sewing pattern 401 “zigzag stitch”, the swing amount 402 “2.0 mm”, the feed amount 403 “2.5 mm”, and the sewing speed 404 “medium speed (410 rpm)” are stored. Corresponding to the color “purple”, the sewing pattern 401 “zigzag stitch”, the swing amount 402 “3.5 mm”, the feed amount 403 “1.4 mm”, and the sewing speed 404 “high speed (750 rpm)” are stored. Corresponding to the color “pink”, the sewing pattern 401 “blind stitch”, the swing amount 402 “0 mm”, the feed amount 403 “2.0 mm”, and the sewing speed 404 “low speed (70 rpm)” are stored. Corresponding to the color “sky blue”, the sewing pattern 401 “blind stitch”, the swing amount 402 “0 mm”, the feed amount 403 “2.0 mm”, and the sewing speed 404 “medium speed (410 rpm)” are stored. Corresponding to the color “red”, the sewing pattern “STOP” to stop sewing control processing is stored.

Next, a specific example of sewing procedures will be described below with reference to FIG. 12, in a case where the sewing control processing is performed according to the flowcharts shown in FIGS. 8 and 9. FIG. 12 shows a condition in which pins 601 to 603 are disposed on the work cloth 60 for sewing. Prior to sewing with the sewing machine 1, the operator sticks the pins 601 to 603 through the work cloth 60 to be fixed in such a manner that respective head portions 611 to 613 of the pins 601 to 603 may be disposed on the right sides of desired positions to be sewn. In an example shown in FIG. 12, a total of three pins 601 to 603 are disposed. The respective head portions 611 to 613 of the pins 601 to 603 have the colors “blue” (head portion: 611), “green” (head portion 612), and “red” (head portion 613) in this order starting from the rear side of the sewing machine 1.

Sewing may be started at the upper end of a dash-and-dot line 61 shown in FIG. 12 (the rear side of the sewing machine 1) (S11 and S13). If start of sewing is instructed (YES at S13), the image sensor 30 in the sewing machine 1 captures images of the work cloth 60, and performs processing to sequentially recognize the colors of the head portions 611 to 613 of the pins 601 to 603 (S15). The color recognition processing may employ a single panel method of, for example, separating image information into three colors RGB (red, green, and blue) with a color filter. Intensities of the respective colors are compared, and the colors included in the image information may be recognized. As a result of executing the color recognition processing, the color of the head portion 611 of the pin 601 is determined as “blue” and sewing conditions corresponding to the color is read out from the sewing condition storage area 203 of the ROM 102 and identified (YES at S17→S18). Then, actual sewing conditions stored in the actual sewing condition storage area of an RAM 103 are changed to the sewing pattern of a “straight stitch”, the swing amount of 0 mm, the feed amount of “1.4 mm”, and the sewing speed of a “low speed (70 rpm)” (S33 to S43). Based on the thus changed actual sewing conditions, sewing may be performed (S45).

Subsequently, the needle drop hole 131 in the presser foot 13 reaches to the left of an area where the pin 602 having the “green” head portion 612 is disposed. At this timing, an image of the head portion 612 of the pin 602 is captured by the image sensor 30 so that the color may be recognized (S15). The sewing conditions corresponding to the color “green” are read out from the sewing condition storage area 203 of the ROM 102 and identified (YES at S17→S18). Then, the actual sewing conditions stored in the actual sewing condition storage area of the RAM 103 are changed to the sewing pattern of a “zigzag stitch”, a swing amount of “2.0 mm”, a feed amount of “1.4 mm”, and a sewing speed of a “low speed (70 rpm)” (S33 to S43). Based on the thus changed actual sewing conditions, sewing may be performed (S45).

Subsequently, the needle drop hole 131 in the presser foot 13 reaches to the left of an area where the pin 603 having the “red” head portion 613 is disposed. At this timing, an image of the head portion 613 of the pin 603 is captured by the image sensor 30 so that the color may be recognized (S15). The sewing conditions corresponding to the color “red” are read out from the sewing condition storage area 203 of the ROM 102 and identified (YES at S17→S18). Because the sewing pattern corresponding to the “red” is “STOP” (YES at S21), sewing is stopped (S27). Sewing may be performed in such a manner, and the patterns of “straight stitch” and “zigzag stitch” are sewn in this order from the rear side of the sewing machine 1, along the dash-and-dot line 61 on the work cloth 60.

As described above, the pins 601 to 603 may be disposed onto a work cloth beforehand so that images of the respective head portions 611 to 613 of the pins 601 to 603 may be captured by the image sensor 30 provided in the sewing machine 1. From the image information obtained by image capturing, the colors of the head portions 611 to 613 may be recognized. Then, sewing may be performed based on the sewing conditions corresponding to the recognized colors. Accordingly, the operator need not need to change the sewing conditions during sewing. Therefore, even if the operator is not skilled in sewing operations, the operator can sew a pattern based on a combination of complicated sewing conditions.

The following will describe a sewing machine 1 according to the third embodiment of the present disclosure with reference to the drawings. Like the second embodiment, the third embodiment is almost the same as the first embodiment described above, except for the contents of the appearance feature recognition processing (see S15 in FIG. 8). Therefore, the description of the same configurations and processing shown in FIGS. 1 to 4, 8, and 9 will be omitted below.

In contrast to the first and second embodiments, in the third embodiment, processing of recognizing the density of the head portions 51 of the pins 50 (hereinafter referred to as “density recognition processing”) may be performed. The density recognition processing is another example of the appearance feature recognition processing. For this purpose, a density of the head portions 51 in a case where a plurality of the pins 50 are disposed on the work cloth is correlated with the sewing conditions (the sewing pattern, the swing amount, the feed amount, and the sewing speed) and stored in the sewing condition storage area 203 of the ROM 102. When sewing is performed, images of the head portions 51 of the pins 50 disposed on the work cloth may be captured by the image sensor 30, and the density of the head portions 51 in the target area may be determined. The sewing conditions that correspond to the density are read out from the sewing condition storage area 203 of the ROM 102 and identified. Then, based on the identified sewing conditions, sewing may be performed.

The sewing conditions stored in the sewing condition storage area 203 of the ROM 102 will be described in detail below with reference to FIG. 13. The sewing condition storage area 203 of the present embodiment stores the sewing conditions for each of densities of the head portions 51 of the pins 50. Specifically, as shown in FIG. 13, the stored sewing conditions may include a sewing pattern 411, a swing amount 412, a feed amount 413, and a sewing speed 414 for each density. Because the densities of the head portions 51 of the pins 50 are correlated with the sewing conditions, it may be easy for the operator to visually recognize the sewing conditions when the pins 50 are disposed on the work cloth.

In an example shown in FIG. 13, corresponding to the density of the head portions 51 of the pins 50 “low”, the sewing pattern 411 “straight stitch”, the swing amount 412 “0 mm”, the feed amount 413 “2.5 mm”, and the sewing speed 414 “medium speed (410 rpm)” are stored. Corresponding to the density “medium”, the sewing pattern 411 “zigzag stitch”, the swing amount 412 “2.0 mm”, the feed amount 413 “1.4 mm”, and the sewing speed 414 “medium speed (410 rpm) are stored. Corresponding to the density “high”, the sewing pattern 411 “blind stitch”, the swing amount 412 “0 mm”, the feed amount 413 “2.0 mm”, and the sewing speed 414 “medium speed (410 rpm)” are stored. It is to be noted that the densities may be classified as “low”, “medium”, and “high” in accordance with, for example, the number of the head portions 51 of the pins 50 recognized in the target area.

Next, a specific example of sewing procedures will be described below with reference to FIG. 14, in a case where the sewing control processing is performed according to the flowcharts shown in FIGS. 8 and 9. FIG. 14 shows a sewing pattern sewn on the work cloths 60 in a condition where pins 701 and 702 are disposed on the work cloths 60. Prior to sewing with the sewing machine 1, the operator sticks the pins 701 and 702 through the work cloths 60 to be fixed in such a manner that respective head portions 711 and 712 of the pins 701 and 702 may be disposed on the right sides of desired sewing positions. In an example shown in FIG. 14, the pins 701 are disposed in a low density and the pins 702 are disposed in a high density in this order from the rear side of the sewing machine 1.

Sewing may be started at the upper end of a dash-and-dot line 61 shown in FIG. 14 (rear side of the sewing machine 1) (S11 and S13). If start of sewing is instructed (YES at S13), the image sensor 30 in the sewing machine 1 captures an image of the work cloth 60, and the CPU 101 performs the density recognition processing to recognize the density of the head portions 711 of the disposed pins 701 (S15). The density recognition processing may be executed by, for example, determining how many head portions 711 and 712 of the pins 701 and 702 are present in the target area. The shapes of the head portions 711 and 712 may be recognized by the shape recognition processing of the first embodiment. As a result of executing the density recognition processing, the density of the head portions 711 of the pins 701 may be determined as “low”, and the sewing conditions corresponding to the density is read out from the sewing condition storage area 203 of the ROM 102 and identified (YES at S17). The actual sewing conditions stored in the actual sewing condition storage area of the RAM 103 are set to be the sewing pattern of a “straight stitch”, the swing amount of “0 mm”, the feed amount of “2.5 mm”, and the sewing speed of a “medium speed (410 rpm)” (S33 to S43). Based on the thus set actual sewing conditions, sewing may be performed (S45).

Subsequently, the presser foot 13 reaches to the left of a portion where the head portions 712 of the pins 702 are disposed in the high density. At this timing, an image of the head portions 712 of the pins 702 are captured by the image sensor 30 so that the density may be recognized (S15). The sewing conditions corresponding to the density “high” are read out from the sewing condition storage area 203 of the ROM 102 and identified (YES at S17). The actual sewing conditions stored in the actual sewing condition storage area of the RAM 103 are changed to the sewing pattern of a “blind stitch”, the swing amount of “0 mm”, the feed amount of “2.0 mm”, and the sewing speed of a “medium speed (410 rpm)” (S33 to S43). Based on the thus changed actual sewing conditions, sewing may be performed (S45).

Subsequently, the operator may press the start-and-stop switch 91 once (YES at S14). With this, sewing may be stopped (S12). The sewing control processing may be executed in such a manner, and the patterns of “straight stitch” and “blind stitch” may be sewn in this order from the rear side of the sewing machine 1, along the dash-and-dot line 61 on the work cloth 60.

As described above, the pins 701 and 702 may be disposed beforehand onto the work cloth as a sewing target so that images of the respective head portions 711 and 712 of the pins 701 and 702 may be captured by the image sensor 30 provided in the sewing machine 1. From the image information obtained by image capturing, the densities of the head portions 701 and 702 may be recognized. Then, the sewing control processing may be performed based on the sewing conditions corresponding to the recognized densities. Accordingly, the operator may not need to change the sewing conditions during sewing. Therefore, even if the operator is not skilled in sewing operations, the operator can sew a pattern based on a combination of complicated sewing conditions.

It is to be noted that, of course, the sewing machine 1 of the present disclosure is not limited to the embodiments described above and can be modified variously without departing from the gist of the present disclosure. For example, in the embodiments described above, the pins 50 are disposed on the work cloth 60 beforehand so that images of the head portions 51 of the pins 50 may be captured by the image sensor 30 in the sewing machine 1 to recognize the appearance features of the work cloth on which the pins are disposed. Then, the sewing conditions are identified according to the recognized appearance features. In a modified embodiment, for example, stickers 801 to 804 (see FIG. 15) may be employed as substitutes for the pins 50. Sewing control processing with use of the stickers 801 to 804 according to the modified embodiment will be described below with reference to FIG. 15.

As shown in FIG. 15, the stickers 801 to 804 have a plurality of different planar shapes (“star” (801), “triangle” (802), “circle” (803), and “character X” (804)). Each of the stickers 801 to 804 has an adhesive layer formed on one of the surfaces and can be stuck to the work cloth 60 with the adhesive layer. Therefore, as in the case of the pins 50 described above, it may be possible to identify a position where sewing with a desired sewing style is to be started or ended. Prior to actual sewing, as shown in FIG. 15, the operator may stick the stickers 801 to 804 to desired positions on the work cloth 60 at which sewing is to be started or ended based on the sewing conditions that are correlated with the respective shapes of the stickers 801 to 804. After the work cloth 60 is placed on the bed portion 2 of the sewing machine 1, like the embodiments of the pins 50 described above, images of the stickers 801 to 804 may be captured by the image sensor 30 sequentially, and the shapes of the stickers 801 to 804 may be recognized. The sewing conditions that correspond to the recognized shapes may be identified, and the sewing machine motor 77, the needle bar swinging motor 78, and the feed adjustment motor 76 may be controlled based on the identified sewing conditions. Because the stickers 801 to 804 do not have the needle portions 52 in contrast to the pin 50, the stickers 801 to 804 may be easy to handle. On the other hand, the work cloths cannot be temporarily secured when sewn up, so that a basting thread etc. may be separately used to temporarily secure the work cloths along a path for actual sewing by the sewing needle 16.

In the above embodiments, the shape, the color, and the density of the head portions 51 are employed as examples of the appearance features of the work cloth recognized from the image information obtained by image capturing of the work cloth on which the head portions 51 of the pins 50 are disposed. Further, any one of the shape the head portion 5, the color the head portion 5, and the density of the head portions 5 is correlated with the sewing conditions (the sewing pattern, the swing amount, the feed amount, and the sewing speed), and the actual sewing conditions are identified to perform sewing. However, the present disclosure is not limited to the embodiments. For example, the sewing conditions may be correlated with a combination of a plurality of the appearance features, and the actual sewing conditions may be identified according to the combination. The sewing conditions, that is, the sewing pattern, the swing amount, the feed amount, and the sewing speed, may be separately correlated with the different appearance features, that is, the shape, the color, and the density. Specifically, for example, the sewing pattern may be correlated with the shape of the head portions 51, the swing amount may be correlated with the color of the head portions 51, and the feed amount may be correlated with the density.

In the above embodiments, the four sewing conditions (the sewing pattern, the swing amount, the feed amount, and the sewing speed) are correlated with the appearance feature of the head portions 51 of the pins 50. However, only any one of those sewing conditions may be correlated with the appearance feature. The actual sewing conditions may be identified according to any one of those sewing conditions that corresponds to the recognized appearance feature.