JP3151923B2 - Buttonhole sewing device for zigzag sewing machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a buttonhole sewing apparatus.

[0002]

2. Description of the Related Art Conventionally, a buttonhole sewing apparatus of this type is disclosed in Japanese Patent Application Laid-Open No. 54-4647. As shown in FIG. 7, the buttonhole sewing device is provided on a presser fitting 50 mounted on a presser bar of the sewing machine to press a work cloth, and a presser fitting 50 slidably in a cloth feeding direction and a counter cloth feeding direction. It is constituted by the press frame 52. A needle plate 58 having a needle hole 56 through which the sewing needle 54 is inserted is provided below the presser frame 52.
A sensor 60 is provided on the needle plate 58 so as not to hinder the sliding movement of the holding frame 52. Furthermore, presser frame 5
A magnet band 62 is provided on the side surface of the sensor 2, and a pulse is generated from the sensor 60 by the magnet band 62. Thereby, a pulse is generated with the movement of the presser frame 52,
The position of the presser frame 52 is detected. A known measuring device for measuring the size of the button is provided on the sewing machine main body.

When a buttonhole of a desired size is sewn by the buttonhole sewing apparatus having such a structure,
First, the size of the button is measured by a measuring device provided on the sewing machine main body. Then, the size of the button measured by the measuring device is counted and input to the first counter provided in the sewing machine main body and stored.

After that, when buttonhole sewing is started,
First, a button hole bar tack 70a shown in FIG. 6 is formed, and then sewing of the L side 70b portion of the button hole is started. Then, the presser frame 52 moves together with the work cloth in the direction of arrow B, and in response to this movement, pulses are sequentially generated from the sensor 60 and are counted and input to the second counter. At this time, the contents of the second counter and the contents of the first counter are compared.

As described above, when sewing the L side 70b portion of the buttonhole on the work cloth, the contents of the first counter that counts the size of the button and the second counter that counts the position of the presser frame 52 are input. The contents of the counters are compared with each other, and when the contents of the two first and second counters match, sewing of the L side 70b is stopped, and the bar tack 70c is formed next. Then, the R side 70d is formed similarly to the formation of the L side 70b, and the sewing of the buttonhole is completed.

[0006]

However, the buttonhole device as described above has a measuring device for measuring the size of the button for forming the buttonhole, and a sensor 60 for detecting the position of the holding frame 52. Were required. For this reason, there is a problem that a variation in component accuracy caused by a product becomes large and a buttonhole of an accurate size cannot be formed in some cases. Further, there is a problem that the cost is high because the number of parts is large. Furthermore, since a complicated electronic circuit and arithmetic processing were required to collate the measurement value measured by the measuring device with the detection value detected by the sensor 60, there was a problem that the cost was high.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and is a simple device capable of detecting the size of a button by one detecting device and detecting the size of a buttonhole to be formed. It is an object of the present invention to provide a buttonhole sewing device which can be formed at a low cost with a simple configuration and can form a buttonhole having an accurate size.

[0008]

In order to achieve this object, a buttonhole sewing apparatus according to the present invention comprises a presser fitting mounted on a presser bar as shown in FIG. 1, and a cloth feeding direction mounted on the presser fitting. And a presser frame movable in the anti-cloth feeding direction, and a button base which is provided movably on the presser frame and can pinch a button in cooperation with the presser frame, and is mounted on a presser fitting,
A detection device for generating a variable output signal, and a detection device provided on a button base , wherein the detection device is variable according to the size of the button.
An operation tool for changing the level value of the output signal, and further detecting a level value of the variable output signal that changes according to the size of the button, and detecting the level value of the variable output signal according to the movement of the presser frame. detecting the level value of the changing variable output signal, said both variable
And control means for controlling to form a buttonhole corresponding to the size of the button based on a comparison operation of the level values of the variable output signals .

[0009]

In the buttonhole sewing apparatus according to the present invention having the above-described structure, the holding member is mounted on the holding bar, and the button base movably provided on the holding frame mounted on the holding member has the holding frame. When the button is pinched in cooperation with the control unit, the operation tool provided on the button base changes the variable output signal generated from the detection device, and the control unit detects the variable output signal that changes according to the size of the button. At the same time, it detects a variable output signal that changes according to the movement of the presser frame in the cloth feed direction and the counter cloth feed direction, and compares the level values of both variable output signals.
Based on the calculation, control is performed so as to form a buttonhole corresponding to the size of the button.

[0010]

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

First, the configuration of the buttonhole device of the present embodiment will be described with reference to FIG.

The buttonhole device of the present embodiment includes a presser fitting 10 mounted on a presser bar attached to the sewing machine main body,
The presser fitting 10 is provided with a presser frame 12 slidably provided in a work cloth feed direction and a counter cloth feed direction. A spiral spring 13 is mounted inside a hollow stopper 12a fixed to the upper surface of the end of the presser frame 12 in the direction of arrow A. The presser frame 12 is constantly urged by the elastic force of the spiral spring 13 so that the presser fitting 10 and the stopper 12a come into contact with each other as shown in FIG. 3, that is, the buttonhole sewing start position. Have been.

Further, the button base 1 extends over the inside and outside of the holding portion 12b which is the end of the holding frame 12 in the direction of arrow B shown in FIG.
4 is provided so as to be slidable, and the button 16 can be held between the end portion 14a of the button base 14 outside the holding portion 12b and the holding portion 12b.

A potentiometer 18 corresponding to a detecting device is attached to the holding metal fitting 10 so as to extend outside the holding frame 12 and be parallel to the holding frame 12.
b. Detecting unit 2 connected to the tip extending from button base 14 in b.
0 is provided. A variable resistor is provided in the potentiometer 18, and the detecting unit 20 is configured to vary the resistance value by sliding in the potentiometer 18.

Here, when the detecting section 20 is located closest to the presser fitting 10, the resistance value is 0. On the other hand, as the detecting section 20 moves away from the presser fitting 10 in the direction B, the resistance value increases. growing. Further, potentiometer ® Nmeta to 18 are lead wires 22 are connected potentiometer 1
8 is connected to the CPU of the sewing machine main body.

Next, the electrical configuration of this embodiment will be described with reference to FIG.
This will be described with reference to FIG.

First, the sewing machine main body is provided with a CPU 24 mainly composed of a microcomputer.
4 is configured to operate in accordance with a flowchart described later, and a pattern selection dial 26 for selecting a desired pattern, a potentiometer 18, and a sewing machine motor start / stop switch 30 are each connected to a CPU 24.
And is configured to supply each signal to the CPU 24. Further, a memory 31 is connected to the CPU 24, and is configured to read and write data in accordance with a signal from the CPU 24.

A pulse motor driver 32 and a sewing machine motor driver 34 are connected to the CPU 24. The pulse motor driver 32 is connected to a needle swing pulse motor 36 and a cloth feed pulse motor 38, respectively. 34 is a sewing machine motor 40
Is connected. In accordance with a signal from the CPU 24, the pulse motor driver 32 issues a command to the needle swing pulse motor 36 and the cloth feed pulse motor 38, and the sewing machine motor driver 34 issues a command to the sewing machine motor 40.

Next, the operation of the buttonhole sewing device according to the present embodiment will be described with reference to FIGS.

First, in the buttonhole sewing apparatus of the present embodiment, the holding member 10 is urged by the elastic force of the spiral spring 13 and the holding member 10 is in contact with the stopper 12a. Then, the button base 14 is pulled in the direction of arrow B from this state, and the button 16 is inserted between the end portion 14a and the holding portion 12b as shown in FIG. Then, the end portion 14a of the button stand is slid in the direction of arrow A until the button 16 comes into contact with the button 16 so that the button 16 is moved to the end portion 14a and the holding portion 1
2b. Then, the presser fitting 10 of the buttonhole sewing device is attached to the cloth presser foot attached to the tip of the needle bar of the sewing machine main body, and the lead wire 22 is connected to the sewing machine main body.

Further, the operation of forming a buttonhole will be described with reference to the flowchart of FIG.

First, when a buttonhole sewing is selected by a pattern selection dial 26 provided on the sewing machine main body, and a start signal for starting the buttonhole sewing by a start / stop switch 30 is sent to the CPU 24 (S1), the CPU2 is started.
4 reads the resistance value R of the potentiometer 18 on which the button 16 is set, and stores it in the memory 31 (S2).
Here, as shown in FIG. 3, since the end portion 14a is isolated from the holding portion 12b because the button 16 is held, the detecting portion 20 is also brought into contact with the potentiometer 18 as well.
And the potentiometer 18 detects a certain resistance value Rn.

Then, the needle swing pulse motor 36 and the sewing machine motor 40 are driven to form the button hole bar tack 70a shown in FIG. 6 (S3). Further, the swing amount is changed, and the cloth feed pulse motor 38 is also driven to move the arrow A.
The work cloth is fed in the direction (S4), the sewing of the L side 70b is performed, and the resistance value R of the potentiometer 18 is read (S6). Then, whether the read resistance value R is 0 or not, that is, the detection unit 20 detects the A of the potentiometer 18
It is determined whether or not the end of the direction has been reached (S
8). If the resistance value R is not 0 (S8: NO), S
Returning to S4, S4 to S8 are repeated. On the other hand, as shown in FIG. 4, when the resistance value R becomes 0 (S8: YES) and the L side 70b of the buttonhole is formed, the bar tack 7
0c is formed (S9), and the process proceeds to S10.

In S10, the cloth feed is reversed by a signal from the CPU 24, and the work cloth is fed in the B direction.
The sewing of the side 70d is performed (S12). Then, the resistance value R of the potentiometer 18 is read again (S1).
4) It is determined whether or not the read resistance value R is the same as the resistance value Rn stored in the memory 31 in S2 (S16). If it is determined that the two resistance values R and Rn are not the same (S16: NO), the process returns to S12, and repeats S12 to S16.
If it is determined that Rn is the same, that is, if the sewing of the R side 70d has been completed (S16: YES), S
Proceed to 18. Then, stop sewing is performed, and the sewing machine motor 4
0 is stopped (S18).

[0025]

As is apparent from the above description, according to the present invention , the button is operated by only one detecting device.
Measure the magnitude as a variable output signal and
During sewing, the position of the presser frame is detected as a variable output signal.
To form a buttonhole of the desired size
You. Therefore, the configuration of the buttonhole sewing device is simplified.
And the accuracy of parts can be kept small.
The buttonhole of the desired size can be formed
You. Also, the number of parts can be reduced,
And can be manufactured at low cost. In addition, one of the detection devices is 1
It can be composed of two potentiometers,
The elimination of arithmetic processing also leads to cost reduction.

[Brief description of the drawings]

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

FIG. 2 is a block diagram showing an electrical configuration of one embodiment of the present invention.

FIG. 3 is a top view of the buttonhole presser at the time of starting sewing in the embodiment.

FIG. 4 is a top view when the buttonhole press is inverted.

FIG. 5 is a flowchart illustrating an operation of a CPU according to the present embodiment.

FIG. 6 is an explanatory view showing an example of a buttonhole to be formed.

FIG. 7 is a perspective view when a conventional device is attached to a sewing machine main body.

[Explanation of symbols]

 DESCRIPTION OF REFERENCE NUMERALS 10 holding bracket 12 holding frame 14 button base 18 potentiometer 20 detection

Claims (1)

(57) [Claims] A buttonhole stitch for forming a buttonhole of a desired size on a work cloth by swinging a sewing needle in a lateral direction and feeding a work cloth in a direction orthogonal to a swing direction of the sewing needle. In the apparatus, a presser fitting mounted on a presser bar, a presser frame mounted on the presser fitting and movable in a cloth feeding direction and a counter cloth feed direction, and provided on the presser frame so as to be movable and cooperate with the presser frame. A button base capable of operating and holding a button, and one that is mounted on the presser fitting and generates a variable output signal.
And detecting device, provided in said button base includes an operation body and for changing the level value of <br/> said variable output signal in accordance with the size of the buttons, depending on the size of the button detects the level value of said variable output signal which changes, detects the level of the variable output signal which varies in accordance with the movement of the pressing frame, the two
Control means for controlling a buttonhole according to the size of the button based on a comparison operation of the level value of the variable output signal, and control means for forming a buttonhole.