JPH0473089A - Sewing machine - Google Patents

Abstract

PURPOSE:To prevent a stitch pattern from being broken by correcting the unbalance of a cloth feeding quantity, in a sewing machine to be composed to permit a feed gear to perform reciprocating motion with a feed motor, even when the actual feeding quantity in the moving-forward direction and in the moving- backward direction is unbalanced. CONSTITUTION:A micro-computer 11 is for controlling sewing operation, and a cloth piece is fed to a feed gear 7 by drive-controlling a pulse motor 10, and the feed is corrected. In a ROM 13, stitch data according to various patterns are stored to be read out by the micro-computer 11 via a data converter 14. In this case, in the stitch data, zigzag data for moving a sewing needle together with feed data for feeding the cloth piece with the feed gear 7 are stored by the number of stitches in order. In this case, when the positive correcting key 16a and the negative correcting key 16b of a setting circuit 16 are set, then according to the operation of the correcting key 16a or 16b, the setting input of a correcting level to the micro-computer 11 is provided, and according to the setting input, the feed data is corrected.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a sewing machine in which the reciprocating motion of a feed dog in a cloth feeding direction is driven and controlled by a feed motor.

(Prior Art) Generally, a mechanism for feeding fabric in a sewing machine has the following configuration. That is, the fabric placed on the throat plate is elastically held by the presser foot, and in this state, the fabric is sewn by vertically driving and horizontally reciprocating the feed dog that is provided on the throat plate surface so that it can freely protrude and retract. It is configured to send out in the direction.

In this case, conventional general sewing machines have a structure in which the feed dog is driven vertically and horizontally reciprocated by mechanically transmitting power from a main shaft drive motor via a cam mechanism. The feeding direction can be changed by a reversing machine.

By the way, in the small electronically controlled sewing machines that have become popular in recent years, incorporating the mechanical power transmission structure described above would complicate the structure and make it difficult to downsize. Some devices are equipped with a pulse motor. This is a machine that feeds the fabric in the sewing direction by controlling a pulse motor using a control means such as a microcomputer based on feed data stored inside the sewing machine.By rotating the pulse motor in the opposite direction, The direction of fabric feeding can be reversed. Therefore, a mechanical configuration such as the above-mentioned reversing machine is not required, and space can be saved.

(Problem to be Solved by the Invention) In a sewing machine configured to reciprocate the feed dog using a pulse motor as described above, even if the pulse motor is rotated by an accurate predetermined amount, the mechanical dimensions of the feed mechanism Due to errors or differences in the force of the presser foot pressing the fabric, the lance between the forward and backward feed rates may be slightly distorted. However, this degree of imbalance does not pose a problem in normal seam formation, so in a sewing machine configured to use such a pulse motor, it is difficult to provide an adjustment mechanism due to its structure. - There was no configuration for adjusting the balance of feed amount in boat fishing.

However, some of the zigzag sewing machines that have become popular in recent years are capable of forming large patterns, such as one pattern made of 100 to 200 stitches, and when forming such large patterns, the balance described above is required. Due to the misalignment, the errors accumulate during the formation of a large number of stitches, resulting in a disordered stitch pattern, which in turn deteriorates the appearance.

The above situation will be explained by taking a stitch pattern as shown in FIG. 5(a) as an example. Now, assume that the balance is shifted so that the amount of cloth feed decreases in the opposite direction to the cloth feed direction, that is, in the direction in which the cloth is moved backward. Originally, a diamond-shaped pattern as shown in Fig. 5(a) should be formed, but because the amount of fabric feed in the backward direction is small, the starting point a and the ending point of the pattern are different as shown in Fig. 5(b). This results in a seam pattern being formed with the gaps apart. This is because an error that is hardly noticeable in one stitch is accumulated and appears as the number of stitches increases. In this case,
The situation is such that even large patterns cannot be accurately formed.

Therefore, in order to solve this problem, it is conceivable to correct the pattern data by changing the feed data in advance according to the amount of deviation, for example. However, as described above, this shift differs slightly from machine to machine, so it cannot be set uniformly.

The present invention has been made in view of the above-mentioned circumstances, and its purpose is to enable balance adjustment of the feed amount in a sewing machine configured to reciprocate the feed dog by a feed motor, and to prevent misalignment even in the formation of large stitch patterns. The purpose of the present invention is to provide a sewing machine that does not cause this problem.

[Structure of the Invention] (Means for Solving the Problems) The present invention includes a feed motor for reciprocating a feed dog in a cloth feed direction, a storage means in which feed data corresponding to the cloth feed amount is stored, The object is a sewing machine equipped with a control means for driving the feed motor according to the feed data read from the storage means, and the feed data for moving the feed dog in a predetermined direction among the feed data read from the storage means is used as a sewing machine. A correction means for adding correction data for correcting the feed amount and a setting means for setting the correction data value are provided, and the control means controls the feed motor based on the feed data corrected by the correction means. The feature is that the drive is controlled.

(Function) According to the sewing machine of the present invention, if the actual cloth feed amount is out of balance between forward and backward movements due to the reciprocating movement of the feed dog by the feed motor, the setting means makes corrections according to the deviation. When the data is set, the correction means adds the correction data to the feed data and gives it to the control means, so the feed motor reciprocates the feed dog based on the corrected feed data. . As a result, for example, if the amount of cloth fed by the feed dog does not match the feed data, in other words, when assembly is performed, there is a slight deviation between the forward and backward directions due to component errors or differences in the force of the presser foot. However, it can be corrected depending on the degree of deviation, and the fabric can be fed according to the original feed data. Therefore, even when forming, for example, a large pattern using a program, it is possible to form an accurate stitch pattern without deviation.

(Example) Hereinafter, an example in which the present invention is applied to a zigzag sewing machine will be described with reference to FIGS. 1 to 4.

First, in FIG. 2 showing the fabric feeding mechanism, a main motor 1 for driving a main shaft transmits rotational power to a sewing machine main shaft 4 disposed at the upper part via a drive pulley 2 and a transmission shaft 3. The main motor 1 also has a timing belt 6 which is passed between the lower part of the drive pulley 2 and the rotary shaft pulley 5a.
Rotational power is applied to the hook 5, and the drive pulley 2
A driving force for vertically moving the feed dog 7 is applied by the upper and lower arm set 7a linked to the upper and lower arms 7a. The feed dog 7 is provided with a link mechanism 8 for reciprocating motion in the cloth feeding direction, and a fan-shaped gear 9 is provided at one end of the link mechanism 8. is transmitted.

The forward and reverse rotation of the pulse motor 10 causes the sector gear 9 to reciprocate, and the feed dog 7 to reciprocate in the cloth feeding direction. The fabric is moved forward or backward by reciprocating the feed dog 7 in the cloth feeding direction while timing the vertical movement of the main motor 1.

Although not shown, the sewing machine main shaft 4 is linked to a needle bar provided on the arm of the main body, and drives the needle bar to cause the sewing needle to perform a predetermined sewing operation.

Next, an outline of the electrical configuration for driving the pulse motor 10 will be described with reference to FIG.

The microcomputer 11 controls the sewing operation, has functions as a control means and a correction means, and controls the feed dog 7 by the pulse motor 10 according to a program to be described later.
is driven and controlled to feed the fabric and correct the feeding.

The microcomputer 11 is supplied with pulses from a timing pulse generator 12 that match the timing of the vertical movement of the feed dog 7 by the main motor 1 . A ROM 13 serving as a storage means stores stitch data corresponding to various stitch patterns, and these stitch data are read out by the microcomputer 11 via a data converter 14. In this case, the stitch data is
The zigzag data for moving the sewing needle and the feed data for feeding the fabric using the feed dog 7 are stored in pairs and sequentially for the number of stitches, and at the end of one stitch data An end code is added to indicate the end of the pattern. The data memory 15 includes the microcomputer 11
The microcomputer 11 stores and reads data as necessary. The setting circuit 16, which is a setting means,
Setting operations are performed using the plus correction key 16a and the minus correction key 16b, and correction level settings are input to the microcomputer 11 in accordance with the operations of these correction keys 16a or 16b. The microcomputer 11 corrects the feed data according to a program in response to the setting input, as will be described later.

Now, the operation of this embodiment is divided into two processes: (I) a process of setting correction data, and (n) a process of correcting feed data based on the set correction data. This will be explained with reference to the program flowcharts shown in FIGS. 3 and 4.

(1) Process of setting correction data For example, when inspecting the sewing machine body after assembly, if the balance between the forward and backward directions of the fabric feed by the feed dog 7 is out of balance as described above. Then, set the correction data as follows. In this case, considering the situation shown in Fig. 5(b) described in the conventional example section, the deviation in the amount of cloth feed is determined by, for example, when forming 30 stitches in the forward direction, Assume that the fabric is fed excessively by about one stitch.

First, in this case, the minus correction key 16b of the setting circuit 16 is operated. The microcomputer 11 is the third
When the correction data setting program is started according to the flowchart shown in the figure, the operation input of this minus correction key 16b is accepted.

Now, as the minus correction key 16b has been operated, it is determined in step S1 that it is rNOJ, and the process moves to step S2, where it is determined that it is YESJ and the operation input is accepted. The value is “-5”
”.

This is to ensure that the set value of the correction register "does not exceed the range of -5" to "5", and a similar determination step is provided on the plus side as will be described later.

Since this is the first setting in this state, the value of the correction register r is cleared (r-0), and therefore, rNOJ is determined in step S3, and the process moves to step S4.

The microcomputer 11 subtracts 1 from the value of the correction register r to make it "-11" (r-r -1) in step S4.
. Next, the process moves to step S5, and the value of the correction register r is displayed on a display device (not shown), and in step S6, correction data is set according to the set value of the correction register r. Incidentally, when it is determined in the above-mentioned step S3 that rYEsJ, that is, when the value of the correction register r is "-5", step S4 is jumped and the process proceeds to step S5. Therefore, steps S5 and S6 are essentially unchanged from before the settings.

Now, in the correction data setting process in step S6 described above, the correction level r is set in correspondence with the value of the correction register r.
The following processing is performed as rJ.

In this embodiment, for example, the correction level is "1" or "-".
1", when 50 stitches are formed, the feed data is increased or decreased by one stitch, and the correction level "
2” or “-2”, if 30 stitches are formed, 1
Corrections are made frequently by increasing or decreasing the needle feed data. Then, the microcomputer 11 assigns "50" to the corrected stitch number register m corresponding to this correction level rlJ r-IJ, and assigns "50" to the corrected stitch number register m corresponding to the correction levels r2J and r-2j.
30'' is substituted.

At this point, since the value of the correction register r is "-1", "50" is assigned to the correction stitch number register m in correspondence with the correction level "-1", and after this the program is terminated. Return to the main program. However, in this state, since the above-mentioned correction amount has not been reached, it is necessary to further change the correction level. Therefore, by operating the minus correction key 16b again, the correction level is set to "-2" through the same steps as described above. As a result, "30" is set in the correction stitch number register m.

Incidentally, when the plus correction key 16a is operated, in the above-described correction data setting program, rYESJ is determined in step S1, and the process moves to step S7. The microcomputer 11 determines whether the value of the correction register r is the maximum value "5" in step S7, and sets rNOj
When it is determined that , the value of the correction register r is increased by 1 in step S8 to raise the correction level, and when it is determined that rYEsJ, step S8 is jumped and then step S2
The program ends after this.

(II) Process for correcting feed data in sewing operation In sewing operation, when the start switch is operated with the desired stitch pattern selected by the selection switch provided on the main body,
The microcomputer 11 starts control based on a main program (not shown). In this case, the stitch data corresponding to each stitch pattern is set in pairs of zigzag data for controlling the sewing needle and feed data for controlling the feed dog 7 for the number of stitches, and stored in ROMI B. is stored in The microcomputer 11 sequentially reads these data and controls the sewing needle and the feed dog 7.
If correction data has been set at this time, the feed data is corrected according to the feed data setting program shown in the flowchart of FIG. 4 when reading the feed data.

That is, the microcomputer 11 reads out the send data and stores it in the F register (step PI), and then, if the send data is not an end code, rY in step P2.
It is determined that it is ESJ and the process moves to step P3. Step P
In step 3, it is determined whether the current value in the stitch number counter is an integral multiple of the value ("30") in the correction stitch number register m, and if it is not applicable, it is determined as "NO" and the process moves to step P4. Then, the stitch number counter k is incremented by 1 (+1 to k4-), and this program is ended. Thereby, in the main program, the feed dog 7 is driven and controlled based on the feed data currently stored in the F register, and a predetermined cloth feed is performed. After this, when the value in the stitch number counter reaches 30'', the microcomputer 11 determines rYESJ in step P3 and moves to step P5.
Then, it is determined whether the value of the correction register r is a positive number or not, and in the case of rYEsJ, the process moves to step P6 and the value stored in the F register is incremented by 1, and as in this case, rN
In the case of OJ, the process moves to step P7, where the value stored in the F register is subtracted by 1, and then the program ends via step P4. As a result, in the main program, the pulse motor 10 is driven with a feed amount that is "1" smaller than the read feed data, and the cloth is fed by the feed teeth 7. Therefore, the error in the cloth feed amount accumulated up to the previous time is corrected here.

Thereafter, each time the value in the stitch number counter becomes an integral multiple of the value in the correction stitch number register m, it is judged as rYEsJ in step P3 mentioned above and the cloth feed amount by the feed dog 7 is corrected, thereby increasing the overall feed. There will be no errors in the amount, and the stitch pattern will not be distorted.

According to this embodiment, the deviation in the amount of cloth feed in the forward and backward directions of the feed dog 7 due to drive control of the pulse motor 10 is controlled by operating the plus correction key 16a and the minus correction key 16b of the setting circuit 16. By setting the correction amount,
Since the amount of cloth feed in the forward and backward directions can be adjusted to achieve an appropriate balance, it is possible to form accurate seams without disrupting the seam pattern even when forming large seam patterns. I can do it.

In the above embodiment, the case where correction data for the feed amount is set at the time of inspection after assembling the sewing machine was explained as an example, but the setting of such correction data can be operated by the user as necessary. It is also possible to have a configuration in which:

In addition, in the above embodiment, the case where the cloth feed balance correction is deviated between forward movement and backward movement has been explained, but this is not limited to this, and the case where the cloth is moved from side to side by driving the feed dog in the horizontal direction by the feed motor is explained. It can also be applied to balance correction.

Furthermore, the present invention is not limited to the above embodiments, and various modifications can be made as shown below without departing from the scope of the invention.

Firstly, when setting the correction data, the correction amount is stored in the correction register, but when correction is to be performed during post-assembly inspection, the correction data is stored in the E.
The information may be stored in a non-volatile storage means such as EFROM.

Second, the correction data is set by operating the plus correction key 16a and the minus correction key 16b connected to the setting circuit 16, but for example, by using a digitally settable key switch or a volume control, etc. A configuration using analog setting means may also be used.

Thirdly, adjust the feed data to 1 after forming the stitches.
Although the configuration is such that the cloth feed direction is rotated, the present invention is not limited to this, and for example, a configuration may be adopted in which correction is performed separately for each of the forward and backward cloth feeding directions.

Thereby, the shape of the entire stitch pattern can be corrected without making it look bad.

Fourthly, as mentioned above, in order to correct the seam pattern to make it look good, it is divided into inconspicuous miro parts and conspicuous parts according to the shape of each seam pattern. For example, level "1" is added to the pattern data. If the correction level is "-3", the flag level changes from "1" to "3".
It is also possible to use a correction method such as adding -1'' to each of the sent data up to ''.

Fifth, although the feed data is corrected by drive control in units of 1 pulse of 1° of the pulse motor 10, the unit of drive control of the pulse motor 10 is 1/2 narrower than the width of 1 pulse.
If the configuration is such that the stop can be controlled at an intermediate position using pulses or 1/4 pulses, more inconspicuous correction can be performed.

[Effects of the Invention] As explained above, according to the sewing machine of the present invention, when the correction data is set by the setting means, the correction means corrects the feed data and provides it to the control means, so that the reciprocating motion of the feed dog is Even if the actual amount of cloth feed is out of balance between the forward and backward directions when driven by a motor, this is corrected and the stitch pattern does not become distorted, which is an excellent effect.

[Brief explanation of the drawing]

1 to 4 show an embodiment of the present invention, FIG. 1 is a block diagram of the electrical configuration, FIG. 2 is an external perspective view of the main part,
FIG. 3 is a flowchart of a correction data setting routine, FIG. 4 is a flowchart of a feed data correction execution routine, and FIG. 5 is an explanatory diagram showing a conventional problem. In the drawing, 1 is a main motor, 2 is a drive pulley, 6 is a timing belt, 7 is a feed dog, 8 is a link mechanism, 9 is a sector gear, 10 is a pulse motor (feed motor), 11 is a microcomputer (control means, correction means), 13 is RO
M (storage means), 15 is a data memory, 16 is a setting circuit (setting means), and 16a is a plus correction key.

Claims (1)

[Claims] 1. A feed motor for reciprocating the feed dog in the cloth feed direction, a storage means in which feed data corresponding to the amount of cloth feed is stored, and the feed motor is driven according to the feed data read from the storage means. a sewing machine comprising: a correction means for adding correction data for correcting the feed amount to feed data for moving the feed dog in a predetermined direction among the feed data read from the storage means; a setting means for setting a data value, and the control means drives and controls the feed motor based on the feed data corrected by the correction means.