JPH0631066A - Seam data generating device for sewing machine - Google Patents

Abstract

PURPOSE:To automatically generate embroidery seam data for forming a desired shape by adding a feed deviation of a feed implement and working cloth generated at the time of vertical/horizontal simultaneous feed of the working cloth executed by a feed dog of a sewing machine. CONSTITUTION:In a needle location point memory, XY position data of a needle location point of an embroidery pattern is stored in advance. Based on Y position data, vertical feed data is calculated (S11), and based on X position data, horizontal feed data is calculated (S12). When an accumulated value of a feed deviation of a feed implement and working cloth generated at the time of vertical/horizontal simultaneous feed of the working cloth exceeds a prescribed value, seam data is corrected so as to obviate the deviation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a needle drop point for a work cloth by moving the feeding tool in the longitudinal and lateral directions based on stitch data composed of feed data for defining the feed amount of the feeding tool. The present invention relates to a stitch data creating device for a sewing machine in which is moved to form a stitch pattern.

[0002]

2. Description of the Related Art First, a conventional sewing machine will be described. A bed for supporting a cloth, a feed dog for moving a work cloth supported by the bed in a vertical direction and a horizontal direction in a plane parallel to the bed, respectively. A needle bar that has a needle at its lower end and that reciprocates vertically with respect to the bed, and that can take a plurality of swing positions on an arc locus along the outer circumference of the horizontal shuttle in the lateral direction with respect to the bed, and its needle A needle bar release device that releases the drive connection between the needle bar crank mechanism and the needle bar to stop the needle above the work cloth, and a plurality of needle drop points required to embroider a pattern on the work cloth. , Vertical feed data that defines the vertical feed amount of the feed dog, horizontal feed data that defines the horizontal feed amount, needle swing position data that defines the needle swing position, and the presence or absence of needle bar release by the needle bar release device. The stitch data that represents the needle drop data as a set A sewing machine including a feed tooth and a controller for embroidering a pattern on a work cloth by controlling the moving amount of a feed dog and a step motor that is a drive device thereof, the swing amount of a needle, and the vertical movement of the needle is already known. There is.

When embroidering with a sewing machine of this type, if the maximum size of the pattern in the lateral direction (hereinafter simply referred to as the lateral width) exceeds the swing range that the needle can take, the work cloth is laterally moved by the feed dog. By moving the needle, the shortage of the swinging amount of the needle is compensated. When the lateral feed amount of one feed tooth exceeds the predetermined maximum feedable amount, the needle bar releasing device is operated to laterally feed the work cloth, and then the remaining lateral feed and the needle bar The release device is inoperative to form the seam.

In such a sewing machine, in order to sew an embroidery pattern, it is necessary to create stitch data in advance. If the stitch data created in advance is stored in a storage medium such as a ROM and the stitch data of a desired embroidery pattern is read out as needed, the controller can feed the stitch length data, cross feed data, and stitch data for each stitch. The embroidery pattern is formed by reading the rocking position data and needle drop data, moving the feed dog in the vertical and horizontal directions, and rocking and vertically moving the needle.

In the conventional data creating apparatus, the creator creates longitudinal feed data, lateral feed data, needle swing position data for each needle drop point in order to store the stitch data in a storage medium such as a ROM. The needle drop data was decided and input. However, when the work cloth is fed vertically and horizontally at the same time by the feed dog, an error occurs in which the vertical and horizontal movement amount of the needle drop point does not match the feed amount indicated by the vertical feed data and the horizontal feed data.
The shape of the embroidery pattern changes. This error is caused by the mechanical characteristic that when the work cloth is fed by the feed dog at the same time in the vertical and horizontal directions, the work cloth does not accompany the movement path of the feed tooth and the work cloth shifts or slips from the feed tool. Therefore, in order to obtain the desired shape of the embroidery stitch, the creator calculates an error, newly creates corrected stitch data for the error, and additionally inputs the corrected stitch data.

[0006]

However, since the number of needle drop points in one embroidery pattern has increased with the recent increase in size and complexity of the embroidery pattern, the shape of the embroidery stitch is desired. In addition, it is a very time-consuming and error-prone task for the creator to calculate an error, newly create corrected stitch data for the error, and additionally input it.

The present invention has been made to solve the above-mentioned problems, and an object thereof is to obtain stitch data in a state in which a feed error between a feed tool and a work cloth which occurs at the time of vertical and horizontal simultaneous feed is eliminated. A stitch data creation device for a sewing machine that can be created automatically.

[0008]

In order to achieve this object, a stitch data creating device for a sewing machine according to a first aspect of the present invention, as shown in FIG.
Needle drop point data storage means for storing vertical position data that defines the position in the vertical direction and horizontal position data that defines the position in the horizontal direction, and the vertical position data of the feed dog from the vertical position data of the needle drop point. A stitch data calculating means for calculating the vertical feed data for defining the feed amount for each needle drop point, and for calculating the horizontal feed data for defining the feed amount in the lateral direction of the feed dog from the lateral position data for each needle drop point. And a feed error caused by a difference between the feed amount of the feed tool calculated by the stitch data calculation means and the feed amount of the work cloth by the feed tool when the work cloth is simultaneously fed in the vertical and horizontal directions. When the accumulated error obtained by accumulating the calculated feed errors exceeds a predetermined value, there is a stitch correction means for eliminating the accumulated error.

Further, in order to achieve this object, in the stitch data creation device for a sewing machine according to claim 2 of the present invention, when the accumulated error exceeds a predetermined value, the stitch data calculation means at that time calculates the stitch error. The sewing machine has stitch correction means for correcting and calculating stitch data composed of vertical feed data and horizontal feed data.

Further, in order to achieve this object, a stitch data creating device for a sewing machine according to a third aspect of the present invention further includes needle drop data which defines presence / absence of needle drop as stitch data. If the accumulated error exceeds the specified value, the needle drop data in the stitch data representing the needle drop point at that time is corrected without needle drop and new stitch data for the corrected stitch is created and inserted. It has a seam correction means.

[0011]

In the stitch data creating device according to the first aspect of the present invention, the lateral position data that defines the lateral position of each of the plurality of needle drop points is stored in the needle drop point data storage means. It The stitch data calculation means calculates vertical feed data for each needle drop point from the vertical position data of the needle drop point, and lateral feed data for each needle drop point from the lateral position data of the needle drop point. The stitch correction means is
A feed error caused by a difference between the feed amount of the feed tool calculated by the stitch data calculation means and the feed amount of the work cloth by the feed tool when the work cloth is fed simultaneously in the vertical direction and the horizontal direction is calculated. When the cumulative value of the calculated feed errors exceeds a predetermined value, the cumulative error is canceled.

In the stitch data creating device according to the second aspect of the present invention, when the cumulative error exceeds the predetermined value, the stitch correcting means and the longitudinal feed data representing the needle drop point at that time and the lateral feed data. The accumulated error is eliminated by correcting and calculating the stitch data composed of the feed data.

In the stitch data creating device according to the third aspect of the present invention, when the cumulative error exceeds the predetermined value, the stitch correcting means and the vertical feed data and the lateral feed data representing the needle drop point at that time. Of stitch data consisting of feed data and needle drop data, the needle drop data is corrected without needle drop, and the accumulated error is eliminated by newly creating and inserting the stitch data of the corrected stitch. .

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

First, as shown in FIG. 2, the sewing machine according to the present embodiment has a needle which is moved up and down across a needle hole 10 formed through a needle plate T which constitutes a sewing machine bed on which a work cloth is placed. 11, a horizontal full rotary hook 13 arranged below the needle plate T to cooperate with the needle 11 to form a stitch on the work cloth, and is arranged in the opening of the needle plate T and appears on the upper surface of the needle plate. It has feed dogs 20 for respectively moving in a vertical feed direction (Y direction in the drawing) and a horizontal feed direction (X direction in the drawing) at a predetermined feed pitch.

As shown in FIG. 3, the control device of the sewing machine is as follows.
CPU30, ROM31 and R, which are the core of the logical operation circuit
Stitch data memory 33 consisting of AM 32 and EEPROM
And an input / output circuit 35 are connected to each other via a common bus 34. A sewing machine motor 41, a vertical feed step motor 43, a horizontal feed step motor 44, and a needle bar release solenoid 45 are connected to the input / output circuit 35 via drivers 36 to 40, respectively. The needle bar releasing solenoid 45 controls a known needle bar releasing device, and the needle bar releasing device releases the drive connection between the needle bar crank mechanism and the needle bar by exciting the solenoid 45, and the needle bar (needle 11). ) Is stopped above the work cloth and only the relative feed between the needle and the work cloth is performed, and the needle bar crank mechanism and the needle bar are connected by demagnetization to reciprocate the needle bar up and down.

The ROM 31 reads the stitch data stored in the stitch data memory 33 for one stitch in response to the detection of a specific rotation phase of the spindle rotated by the sewing machine motor 41, and the vertical feed step motor 43. A program for driving and controlling the lateral feed step motor 44 and the needle bar release solenoid 45 is stored. This stitch data is created for each feed control unit for one time, with the vertical feed data, the horizontal feed data, and the needle bar release data as a set, and the stitch data memory 3
Stored in 3. The feed control unit indicates the drive amount of vertical and horizontal feed of the feed dog performed during one rotation of the main shaft of the sewing machine regardless of whether the needle moves up and down.

As a mechanical characteristic of this sewing machine, the feed amount for one step of the vertical feed step motor 43 for moving the feed dog 20 in the Y direction in FIG. 2 is set to 0.34 mm. The lateral feed step motor 44 that is moved in the X direction in FIG.
It is set to 675 mm. The vertical feed data of the vertical feed step motor 43 is given in a format in which plus and minus signs are added to the number of steps. A plus value indicates plus feed, and a minus value indicates reverse feed. . Similarly to the vertical feed data, the horizontal feed data of the horizontal feed step motor 44 is given in a format in which the plus and minus signs are added to the number of steps. In the case of the plus value, the work cloth is viewed from the work feed side. Is sent to the left, and a negative value indicates that the work cloth is sent to the right when viewed from the work cloth feeding side.

When the work cloth is moved only in the lateral direction, that is, when the lateral feed step motor 44 alone is fed by one step or more, the movement amount of the work cloth is the lateral feed step motor 44 feeding by one step. Although it corresponds to 0.675 mm set as the amount, when the work cloth is simultaneously moved in the vertical direction and the horizontal direction, that is, the vertical feed step motor 4
It has been confirmed by an experiment that the feed amount per step of the lateral component of the moving distance of the work cloth is 0.7 mm when 3 and the lateral feed step motor 44 are simultaneously operated for one step or more.

The needle bar release data indicates whether or not the needle 11 has fallen onto the work cloth. When the needle bar release data is "0", the needle bar release solenoid 45 of the needle bar release device of the sewing machine does not operate. When the needle bar crank mechanism is connected to the needle bar and the needle bar is moved up and down, when the needle bar release data is "1", the needle bar release solenoid 45 is excited and the needle bar crank mechanism and the needle bar are excited. It means that the connection with is released and the needle bar stops.

It is necessary to store the stitch data in the stitch data memory 33 before forming the embroidery stitch using the sewing machine configured as described above. The configuration of the data creation device 50 for creating this stitch data will be described below.

As shown in FIG. 4, the data creating apparatus 50 includes a CPU 51, which is the center of a logical operation circuit, a ROM 52 storing a program for driving the CPU 51, and a RAM 53, via a common bus 54. They are connected to each other. In the ROM 52, the feed amount per step (= 0.675 mm) by the lateral feed step motor 44 alone and the feed amount per step (= 0.75 mm) when the vertical feed step motor 43 is simultaneously operated.
7 mm) and the value of the pitch error data (= 0.025 mm) due to the difference between the two feed amounts are stored in the ROM 52 in advance. Also, the needle drop point is
Digitizer 55 for inputting direction position data
Is connected, and a needle drop point memory (needle drop point data storage means) 60 for storing the needle drop point data input by the digitizer 55 is connected to the stitch data memory 3
PROM writer 61 for writing stitch data in 3
Are connected through the output port.

Further, a stitch data area and an error area are set in the RAM 53, and in this stitch data area, the vertical feed data of the feed dog 20 and the feed tooth 20 corresponding to each needle drop point are set. The horizontal feed data and the needle bar release data indicating the presence / absence of needle drop of the needle 11 are stored. The needle bar release data is set to 0 in advance for each needle drop point. On the other hand, in the error region, error data is stored corresponding to each needle drop point, which is a standard for whether or not to correct the stitch.

Next, creation of stitch data by the data creating device 50 will be described with reference to the flow chart of FIG.

First, a coordinate system shown in FIG. 6 is set based on the Y axis in the longitudinal feed direction of 0.34 mm on one scale and the X axis in the transverse feed direction of 0.675 mm on one scale, and the pattern " The desired needle drop points P1 to P37 of "A" are determined. That is, the digitizer 55 causes points P1 to P1 in FIG.
The point P37 is designated, and the position data in the XY directions of each point is stored in the needle drop point memory 60 as needle drop position data. The position data in the XY directions of these points P1 to P37 are as shown in the table of FIG.

First, the CPU 51 reads the position data of the needle drop point from the needle drop point memory 60 and stores it in a predetermined area of the RAM 53 in step 1 (step S1; the following step is abbreviated as S).

Next, the CPU 51 calculates the stitch data for forming the stitch at each needle drop point and the error data as a guide for whether or not to correct the stitch, and the stitch data area and the error in the RAM 53. Store in the area. This error data is the amount of horizontal movement of the work cloth when the horizontal feed step motor 44 operates independently to move the work cloth in the horizontal direction (= 0.
675 mm) and the vertical feed step motor 43 and the horizontal feed step motor 43 operate simultaneously to move the work cloth in an oblique direction, the lateral movement amount of the work cloth (= 0.7 m).
m) and the pitch error data resulting from the fact that they do not match.

First, the CPU 51 initializes the counter j to 1 in S10.

Next, the CPU 51 sets vertical feed data (= 0) in the case of the needle drop point P1 in S11, and S1
2 sets the traverse data (= 0 mm) and RA
Store in M53.

Next, the CPU 51 proceeds to S13, where S1
When the feed dog 20 is operated by the lateral feed data set by 2, the lateral feed step motor 44 operates independently to move the work cloth in the lateral direction, and the lateral movement amount of the work cloth (= 0. .675 mm) and the vertical feed step motor 43 and the horizontal feed step motor 44 operate simultaneously to move the work cloth in an oblique direction, the lateral movement amount (= 0.7 mm) of the work cloth does not match. Then, the pitch error data resulting from is calculated. In the case of the needle drop point P1, the pitch error data (= 0 m from the lateral feed data (= 0)
m) is calculated and error data (= 0 mm) is stored in the error area of the RAM 53. Next, the CPU 51 executes S
In 14, the absolute value (= 0 mm) of the error data (= 0 mm) calculated in the previous S13 is the movement amount of the lateral feed step motor 44 for one single step (= 0.675).
mm). Next, in S17, the CPU 51 determines all needle drop points Pj.
It is judged that the creation of the stitch data has not been completed, the counter j is incremented in S18, and the process returns to S11.

Next, in S11, the CPU 51 reads the Y-coordinate data (= 4) of the needle drop point P2 and sets the feed amount F, which must be moved by vertical feed for each stitch, to the current needle drop point P2. Needle drop point P1 immediately before from the Y coordinate value
It is obtained by subtracting the Y coordinate value (= 0) of. Since the feed amount F (= 4) corresponds to the number of steps of the vertical feed step motor 43, the CPU 51 stores the feed amount F in the RAM.
It is stored in the stitch data area 53 as vertical feed data for the needle drop point P2.

Next, in S12, the CPU 51 reads the X-coordinate data (= 1) of the needle drop point P2 and sets the feed amount S, which must be moved laterally for each stitch, at the current needle drop point P2. Needle drop point P1 immediately before from the X coordinate value
X coordinate value (= 4) is subtracted to obtain. The feed amount S
Since (= −3) corresponds to the number of steps of the lateral feed step motor 44, the CPU 51 stores the feed amount S in the stitch data area of the RAM 53 as the lateral feed data of the needle drop point P2.

Next, in S13, the CPU 51 moves the work cloth in the lateral direction (= 0.6) when the lateral feed step motor 44 operates independently to move the work cloth in the lateral direction.
75 mm) and the vertical feed step motor 43 and the horizontal feed step motor 44 simultaneously operate to move the work cloth in an oblique direction, the amount of lateral movement of the work cloth (= 0.7 mm)
Pitch error data resulting from the fact that and do not match is calculated. Horizontal feed step motor 44 per 1 horizontal feed data
Move independently to move the work cloth in the horizontal direction, the horizontal movement amount (= 0.675 mm) of the work cloth, the vertical feed step motor 43 and the horizontal feed step motor 44 simultaneously operate to move the work cloth. The difference (= 0.02) from the lateral movement amount (= 0.7 mm) of the work cloth when it is moved in an oblique direction.
5 mm) pitch error occurs.

This pitch error is used as pitch error data, and the plus and minus of the pitch error data is the same as the plus and minus of the lateral feed data. Therefore, the needle drop point P
In the case of 2, the vertical feed data (=
4) and the lateral feed data calculated in S12 (=-
3) and the product of the lateral feed data and the pitch error is calculated, and the CPU 51 determines the pitch error data (= −0.075 m).
m) is calculated. Then, the pitch error data (= -0.075 mm) at the needle drop point P2 is added to the error data (= 0 mm) at the previous needle drop point P1, and the RAM 5 is added.
Error data recalculated to the error region of 3 (= -0.07
5 mm) is memorized.

Next, the CPU 51 determines in S14 the absolute value (= 0.075 mm) of the error data (= -0.075 mm).
mm) is not larger than the movement amount (= 0.675 mm) for one single step of the lateral feed step motor 44. Then, as in the previous step, S17, S
After 18, the process returns to S11.

The needle drop point P is calculated in the same manner.
The case of S11 will be described.
The vertical feed data (= 3) is calculated in S1, and the horizontal feed data (= 3) is calculated in S12.

Next, the CPU 51 proceeds to S13, where S1
Pitch error data (= 0.075 mm) is calculated from the lateral feed data (= 3) calculated in 2. Then, pitch error data (= 0.075 m) at the needle drop point P11 is added to the accumulated error (= 0.625 mm) at the immediately preceding needle drop point P10.
m) is added, and the recalculated error data (= 0.7 mm) is stored in the error area of the RAM 53.

Next, in S14, the CPU 51 determines that the absolute value (= 0.7 mm) of the error data (= 0.7 mm) is larger than the movement amount (= 0.675 mm) of the lateral feed step motor 44 for one single step. Determine that it has grown.

Next, in S15, the CPU 51 creates corrected stitch data for moving the transverse feed step motor 44 in the direction opposite to the direction in which the stitch error occurs. To this end, the CPU 51 causes the accumulated error (= 0.7) at the needle drop point P11.
mm) to determine that a stitch error has occurred in the plus direction, and therefore to move the transverse feed step motor 44 in the minus direction in order to eliminate the plus error at the needle drop point P11. Rewrite the horizontal feed data to.
That is, the lateral feed data (= 3) at the needle drop point P11 is added with the amount of movement (= -1) of the lateral feed step motor 44 for one step in the negative direction, and the lateral feed data is rewritten as (= 2). Then, the rewritten stitch data is stored in the stitch data area of the RAM 53.

Next, in step S16, the CPU 51 moves the lateral feed step motor 44 by one step to the error data (= 0.7 mm) calculated in step S13 because the lateral feed step motor 44 at the correction point is in the negative moving direction. Is added. At this time, the vertical feed data at the needle drop point P11 is "0".
Therefore, the added value is the vertical feed step motor 4
3 and the lateral feed step motor 44 are operated at the same time, the unit pitch (= -0.7 mm) in the lateral feed direction. If the vertical feed data at the needle drop point P11 is “0”, the unit pitch (= −0.675 mm) in the horizontal feed direction when the horizontal feed step motor 44 operates independently will be added. . Then, the CPU 51 stores the recalculated error data (= 0 mm) in the error area of the RAM 53. Then, in order to determine whether the stitch corrected by this rewriting needs to be re-corrected, S14 is again used.
Return to processing. Then, the CPU 51 at S14
The absolute value (= 0 mm) of the error data (= 0 mm) is the amount of movement of the lateral feed step motor 44 for one single step (=
0.675 mm), the process returns to S11 through S17 and S18 as before.

The same operation is performed and the needle drop point P21
In the case of, the CPU 51 calculates the vertical feed data (= -1) in S11, the horizontal feed data (= -5) in S12, and then the horizontal feed data (= -5) calculated in S12 in S13. ), The pitch error data (= -0.125 mm) is calculated. And CP
U51 calculates the accumulated error (= -0.675 mm) and stores the recalculated error data (= -0.675 mm) in the error area of the RAM 53.

Next, in S14, the CPU 51 determines the absolute value (= 0.675) of the error data (= -0.675 mm).
mm) corresponds to a movement amount (= 0.675 mm) for one step of the lateral feed step motor 44.

Next, in S15, the CPU 51 moves the lateral feed step motor 44 in the plus direction.
The amount of movement (= 1) for one step of horizontal feed is added to the horizontal feed data (= -5) to rewrite it as horizontal feed data (= -4). Then, the rewritten stitch data is stored in the stitch data area of the RAM 53.

Next, in S16, the CPU 51 calculates the error data (= 0.675 mm) calculated in S13 because the direction of movement of the lateral feed step motor 44 at the correction point is positive.
Is added to the movement amount for one independent step of the lateral feed step motor 44. At this time, the vertical feed data of P21 is "0".
Therefore, the added value is the vertical feed step motor 4
The unit pitch (= 0.7 mm) in the lateral feed direction when 3 and the lateral feed step motor 44 operate simultaneously. Then, the CPU 51 stores the recalculated error data (= 0.025 mm) in the error area of the RAM 53. Then, in order to determine whether the stitch corrected by this correction needs to be corrected again, the process returns to S14. Then, the CPU 51 determines the error data (=
It is determined that the absolute value of (0.025 mm) (= 0.025 mm) is not larger than the movement amount of the lateral feed step motor 44 for one single step, and the process returns to S11 through S17 and S18.

After this, the stitch data at the needle drop point is similarly created as shown in FIGS. 9 to 10.

After creating the stitch data for the needle drop point P37, the CPU 51 determines in S17 that the stitch data has been created for all the needle drop points Pj, and the stitch data is created. Exit the program for.

When the creation of the stitch data is completed in this way, the creator attaches the stitch data memory 33 to be mounted on the sewing machine to the PROM writer 61 and causes the stitch data memory 33 to store the stitch data area in the RAM 53. The seam data of is stored. In this way, if the stitch data memory 33 storing the stitch data is attached to the sewing machine, the stitch pattern (the pattern "A" in this embodiment) can be formed without losing its shape.

Here, the processing of S11 and S12 of the CPU 51 corresponds to the stitch data calculation means of the present invention, and S13 to S13.
The processing of 16 corresponds to the stitch correcting means according to claim 2 of the present invention. The pitch error corresponds to the feed error of the present invention.

It should be noted that the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the invention. For example, in the present embodiment, the condition for correcting the stitch data is that the accumulated error is the movement amount of one single step of the lateral feed step motor 44. Obviously, if the stitch data is corrected when the amount of movement of the feed step motor 44 becomes half of one step, it is possible to create data such that the needle drops to a point closer to the target needle drop point.

In the above embodiment, the lateral feed data is recalculated to eliminate the stitch error. However, when the accumulated error exceeds a predetermined value, the stitch drop of the stitch data at that time is eliminated. The same correction can be performed by correcting the data without needle drop and newly creating and inserting correction data for moving the feed dog 20. A second embodiment for newly creating and inserting correction data will be described below with reference to the flowchart of FIG. The same components as those in the first embodiment described above are designated by the same reference numerals and the description thereof will be omitted.

The case of the needle drop point P11 where the calculation is performed in the same manner as in the first embodiment will be described.
51 is vertical feed data (= 3) in S11, S12
In step S1, the horizontal feed data (= 3) is calculated.

Next, the CPU 51 proceeds to S13, where S1
Pitch error data (= 0.075 mm) is calculated from the lateral feed data (= 3) calculated in 2. Then, pitch error data (= 0.075 m) at the needle drop point P11 is added to the accumulated error (= 0.625 mm) at the immediately preceding needle drop point P10.
m) is added, and the recalculated error data (= 0.7 mm) is stored in the error area of the RAM 53.

Next, in S14, the CPU 51 determines that the absolute value (= 0.7 mm) of the error data (= 0.7 mm) is larger than the movement amount (= 0.675 mm) of the lateral feed step motor 44 for one single step. Determine that it has grown.

Next, in S25, the CPU 51 corrects the needle drop data of the stitch data at the needle drop point P11 without needle drop. That is, the needle drop data (= 0) at the needle drop point P11 is corrected to no needle drop (= 1). Then, in S26, the CPU 51 newly inserts the stitch data of the corrected stitch A for moving the lateral feed step motor 44 in the direction opposite to the direction in which the stitch error occurs. To this end, the CPU 51 causes the accumulated error (= 0.7) at the needle drop point P11.
mm) to determine that a stitch error has occurred in the plus direction, and therefore to move the transverse feed step motor 44 in the minus direction in order to eliminate the plus error at the needle drop point P11. The stitch data of is added. That is, after the stitch data at the needle drop point P11, the traverse step motor 44 is moved by one step in the minus direction (=
The stitch data of the corrected stitch A of -1) is newly inserted.
Then, the corrected stitch data of the needle drop point P11 and the stitch data of the newly inserted corrected stitch A are stored in the stitch data area of the RAM 53.

Next, in S27, the CPU 51 calculates the error data (= 0.7 mm) calculated in S13 because the moving direction of the lateral feed step motor 44 of the correction stitch A is negative.
Is added to the movement amount (= −0.675 mm) of the lateral feed step motor 44 for one independent step. And CPU
51 stores the recalculated error data (= 0.025 mm) in the error area of the RAM 53. Then, the stitch corrected by inserting the stitch data of the corrected stitch A is
In order to determine whether recorrection is necessary, the process returns to S14. Then, in S14, the CPU 51 determines the absolute value (= 0.025 m) of the error data (= 0.025 mm).
m) is not larger than the movement amount (= 0.675 mm) of the lateral feed step motor 44 for one single step, and S18, S19, S
Returning to the processing of 11.

The same calculation is performed and the needle drop point P22
In the case of, the CPU 51 calculates the vertical feed data (= -1) in S11, the horizontal feed data (= -5) in S12, and then the horizontal feed data (= -5) calculated in S12 in S13. ), The pitch error data (= -0.125 mm) is calculated. And CP
U51 calculates the accumulated error (= -0.775 mm) and stores the recalculated error data (= -0.775 mm) in the error area of the RAM 53.

Next, the CPU 51 determines in S14 the absolute value (= 0.775) of the error data (= -0.775 mm).
mm) is larger than the movement amount (= 0.675 mm) of the lateral feed step motor 44 for one single step.

Next, in S25, the CPU 51 corrects the needle drop data of the stitch data at the needle drop point P22 without needle drop. That is, the needle drop data (= 0) at the needle drop point P22 is corrected to no needle drop (= 1). Then, in S26, the CPU 51 newly inserts the stitch data of the correction stitch B for moving the lateral feed step motor 44 in the direction opposite to the direction in which the stitch error occurs. To that end, the CPU 51 causes the accumulated error (= -0.
775 mm) to determine that the stitch error has occurred in the negative direction, and therefore the transverse feed step motor 44 is moved in the positive direction in order to eliminate the negative error at the needle drop point P22. The stitch data of is added. That is, after the stitch data at the needle drop point P22, the stitch data of the correction stitch B for one step (= 1) of movement in the plus direction of the lateral feed step motor 44 is newly inserted. Then, the corrected stitch data of the needle drop point P22 and the stitch data of the newly inserted correction stitch B are stored in the RAM 5
It is stored in the stitch data area of No. 3.

Next, in S27, the CPU 51 determines that the moving direction of the lateral feed step motor 44 of the corrected stitch B is positive, so the error data calculated in S13 (= -0.775 m).
The movement amount (= 0.675 mm) for one step of the lateral feed step motor 44 is added to m). And CP
The U 51 stores the recalculated error data (= −0.1 mm) in the error area of the RAM 53. Then, the stitch corrected by inserting the stitch data of the corrected stitch B is
In order to determine whether recorrection is necessary, the process returns to S14. Then, in S14, the CPU 51 determines that the absolute value (= 0.1 mm) of the error data (= -0.1 mm) is larger than the movement amount (= 0.675 mm) of the lateral feed step motor 44 for one single step. If it is determined that there is not, the process returns to S11 via S18 and S19 as in the previous case.

After this, the stitch data at the needle drop point is similarly created as shown in FIGS. 12 to 13.

After creating the stitch data of the needle drop point P37, the CPU 51 determines in S18 that the creation of the stitch data has been completed for all needle drop points Pj, and the stitch data is created. Exit the program for.

When the creation of the stitch data is completed in this way, the creator causes the stitch data memory 33 to store the stitch data in the stitch data area of the RAM 53. In this way, if the stitch data memory 33 storing the stitch data is attached to the sewing machine, the stitch pattern (the pattern "A" in this embodiment) can be formed without losing its shape.

Here, S13 and S14, S25 to S2
The processing of No. 7 corresponds to the stitch correcting means according to claim 3 of the present invention.

It should be noted that the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the invention. For example, in the present embodiment, as the condition for adding the stitch data of the corrected stitch, it is assumed that the stitch error is the movement amount of one single step of the lateral feed step motor 44. For example, if the correction stitch data is added when the error of the stitch becomes half of the movement amount of the lateral feed step motor 44 in one single step, the data such that the needle drops to a point closer to the target needle drop point is obtained. Obviously you can create.

Incidentally, in the above-mentioned two embodiments, the feed dog 2 generated when the feed dog 20 feeds the workpiece cloth simultaneously in the vertical and horizontal directions.
The difference caused by the difference between the feed amount on the data of 0 and the actual feed amount of the work cloth is only the difference in the horizontal direction, but the same difference also occurs in the vertical direction. The accumulated error in the vertical direction can be eliminated by the method described above.
In addition, the reference dimension of the grid in FIG. 6 is the feed dog 2 per pitch.
It was based on a vertical feed amount of 0 and a horizontal feed amount of 1
A case based on the vertical feed amount of the feed dog 20 per pitch and the needle swing may be considered, and the lattice in this case places importance on the needle swing. Further, the ROM 52 may store data for correcting not only one type of sewing machine but a plurality of sewing machines.

[0066]

As is clear from the above description,
According to the present invention, if the needle drop point data storage unit stores the vertical position data that defines the vertical position and the horizontal position data that defines the horizontal position of each of the plurality of needle drop points, The stitch data calculating means calculates the vertical feed data for each needle drop point from the vertical position data of the needle drop point, and the horizontal feed data for each needle drop point from the horizontal position data. Calculating a feed error caused by a difference between a feed amount of the feed tool calculated by the stitch data calculation means and a feed amount of the work cloth when the work cloth is simultaneously fed in the vertical direction and the horizontal direction, and
When the accumulated error obtained by accumulating the calculated feed error exceeds a predetermined value, the stitch data is corrected so as to eliminate the accumulated error. The vertical and horizontal feed data of the feeding tool in which the error caused by the feeding is eliminated can be automatically created, and the stitch pattern data of the stitch pattern having a desired shape can be created in a short time. .

[Brief description of drawings]

FIG. 1 is a block diagram showing the present invention.

FIG. 2 is an explanatory diagram showing a relationship among a needle, a feed dog, and a hook of the sewing machine according to the embodiment of the present invention.

FIG. 3 is a block diagram showing an electrical configuration of the sewing machine of the above embodiment.

FIG. 4 is a block diagram of a data creation device according to an embodiment of the present invention.

FIG. 5 is a CPU of the data creating apparatus according to the first embodiment.
It is a flow chart which shows operation of 51.

FIG. 6 is a diagram showing a coordinate system used when creating the stitch data of the above embodiment.

FIG. 7 is an explanatory diagram showing needle drop positions of the stitch pattern “A” in the above-described embodiment.

FIG. 8 is a table showing position data for each of the needle drop positions of the stitch pattern “A” in the above embodiment.

FIG. 9 is a RAM of the data creating apparatus according to the first embodiment.
5 is a table showing stitch data and corrected stitch data stored in a stitch data area 53.

FIG. 10 is an RA of the data creation device according to the first embodiment.
9 is a table showing stitch data and corrected stitch data stored in a stitch data area of M53.

FIG. 11 is a CP of the data creation device of the second embodiment.
It is a flow chart which shows operation of U51.

FIG. 12 is an RA of the data creation device of the second embodiment.
9 is a table showing stitch data and corrected stitch data stored in a stitch data area of M53.

FIG. 13 is an RA of the data creation device according to the second embodiment.
9 is a table showing stitch data and corrected stitch data stored in a stitch data area of M53.

[Explanation of symbols]

 10 Needle hole 11 Needle 13 Horizontal hook 20 Feed dog 33 Stitch data memory 43 Vertical feed step motor 44 Horizontal feed step motor 50 Data creation device 51 CPU 52 ROM 53 RAM 60 Needle entry point memory

Claims (3)

[Claims] 1. The feed device is moved in the vertical and horizontal directions based on the stitch data which is composed of a set of vertical feed data defining the vertical feed amount of the feed device and horizontal feed data defining the horizontal feed amount. Therefore, a stitch data creating device for a sewing machine, which is configured to move a needle drop point with respect to a work cloth to form a stitch pattern, wherein each of the plurality of needle drop points has a position in the vertical direction. Needle position data storing means for storing the vertical position data for defining the vertical position data and the horizontal position data for defining the position in the horizontal direction, and the vertical feed data for each needle position from the vertical position data for the needle position. A stitch data calculation means for calculating the lateral feed data for each needle drop point from the lateral position data, and a feed amount of the feed tool calculated by the stitch data calculation means and the work cloth in the vertical direction. The feed error caused by the difference from the feed amount of the work cloth by the feed tool when being fed simultaneously in the horizontal and horizontal directions is calculated, and the cumulative error obtained by accumulating the calculated feed errors exceeds a predetermined value. In this case, there is provided a stitch data creating device for a sewing machine, which comprises a stitch correcting means for eliminating the accumulated error. 2. When the accumulated error exceeds a predetermined value,
2. The sewing machine according to claim 1, wherein the stitch correction means corrects the stitch data calculated by the stitch data calculation means at that time to eliminate the accumulated error. Eye data creation device. 3. The stitch data is further added with needle drop data defining presence / absence of needle drop, and when the accumulated error exceeds a predetermined value, the stitch correcting means causes the needle drop at that time. The accumulated error is eliminated by correcting needle drop data in the stitch data representing a point without needle drop and newly creating and inserting stitch data of corrected stitches. A stitch data creation device for the described sewing machine.