JPH06104151B2 - Pattern matching sewing machine with a cloth edge detection function - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention is provided with a detection device for detecting the patterns of upper and lower two work cloths arranged in an overlapping manner, and a pattern detection signal from the detection device. The present invention relates to a pattern-matching sewing machine in which the patterns of both work cloths are stitched together while changing the cloth feed amount for at least one work cloth.

(Prior Art) Conventionally, as a sewing machine of this type, for example, JP-A-60-153 is known.
A structure as shown in Japanese Patent No. 896 is known.

In this conventional structure, the pattern of each work cloth is detected by a pair of sensors provided corresponding to the work cloth, and the feed amount of either one of the upper and lower cloth feed devices is fed to the other according to the deviation of the handle. By relatively changing the amount, the relative position of the pair of work cloths is changed to perform pattern matching.

(Problems to be Solved by the Invention) However, in this conventional configuration, the output signals from the pair of sensors are not used for detecting the end portion of the work cloth, so that the sewing machine finishes sewing as compared with the conventional sewing machine. In order to add the function of automatically stopping the sewing machine at the position, a new sensor for detecting the cloth edge is required, which causes a problem of high manufacturing cost.

The present invention has been made in view of the above circumstances,
The purpose is to add a new function of automatically stopping the sewing machine at the sewing end position to the conventional pattern-matching sewing machine without the need to provide a special sensor for detecting the cloth edge and to manufacture at low cost. It is to provide a pattern-matching sewing machine having a cloth edge detection function that can be performed.

Configuration of the Invention (Means for Solving Problems) In order to achieve the above-mentioned object, a pattern-matching sewing machine according to the present invention includes a detection device for detecting patterns of upper and lower two work cloths that are superposed and arranged. It is arranged on the cloth feeding side from the drop point, and is configured to output an edge detection signal when the edge of the work cloth passes, and controls the operation of the sewing machine according to the output of the edge detection signal. A control device is provided.

(Operation) According to the pattern matching sewing machine of the present invention having the above configuration, the patterns of both work cloths are sewn together while changing the cloth feed amount for at least one of the work cloths based on the pattern detection signal from the detection device. At the same time, when the end of the work cloth passes through the detection device, the detection device outputs an end detection signal, and the control device controls the operation of the sewing machine in response to the output.

(Embodiment) Next, an embodiment of the present invention will be described in detail with reference to the drawings.

As shown in FIGS. 1 and 2, a needle plate 2 is mounted on the sewing machine bed 1, and a needle 3 penetrating through the needle plate 2 and moved up and down and a thread loop not shown in the sewing machine bed 1 are captured. By cooperation with the sewing machine, the two work cloths W1 and W2 superposed on the sewing machine bed 1 are sewn to each other. A lower feed dog 4 is arranged under the needle plate 2 in the vicinity of the dropping position of the needle 3 so as to be capable of four-movement feeding. Granted. Upper feed dogs 6 are arranged on both sides of the presser foot 5 so as to be able to feed four movements, and the upper feed teeth 6 additionally feed the upper work cloth W1. In this embodiment, the feed amount of the upper feed dog 6 is relatively changed with respect to the feed amount of the lower feed tooth 4 by the upper feed changing device 7 having a well-known configuration shown in FIG.

The light emitting elements 8a and 9a are respectively provided on the sewing machine bed 1 so as to be positioned at a predetermined distance from the dropping position of the needle 3 to the cloth feeding side and to be opposed to the upper and lower sides of the work cloths W1 and W2.
An upper cloth sensor 8 and a lower cloth sensor 9 including light receiving elements 8b and 9b are arranged to detect the pattern of each of the work cloths W1 and W2 and output a pattern detection signal, and detect the end of sewing to detect the end. The unit detection signal is output (see FIG. 6).

Next, the electrical configuration of the sewing machine in this embodiment will be described with reference to FIG. 4. The central processing unit (CPU) 21 that constitutes the control device is built in the control box 20 shown in FIG. A read only memory (ROM) 22 and a random access memory (RAM) 23 are connected. R
A program for controlling the operation of the entire sewing machine is stored in the OM22, and the RAM23 is provided with an area for storing the pattern detection signal and the edge detection signal of both the work cloths W1 and W2 detected. There is.

Output signals from the upper cloth sensor 8 and the lower cloth sensor 9 are amplified by an amplifier 24, and then converted into digital signals by an A / D converter 25 and input to the CPU 21. In this embodiment, the output level of the amplifier 24 when the work cloths W1 and W2 are not present between the sensors 8 and 9 is
Based on the adjustment of the offset and gain of 24, as shown in FIG. 6, the level is set to a level higher than that in the case where the unpatterned portions of the work cloths W1 and W2 are the white background.

Further, the CPU 21 is connected with a key input section 26 having various keys and a display section 27 for displaying key input data. With the predetermined key operation on the key input section 26, the CPU 21 performs pattern matching sewing. The pattern matching mode for performing the above and the cloth edge stop dedicated mode for automatically stopping the sewing at the processed cloth edge portion are selectively set, and the mode is displayed on the display unit 27 corresponding to each mode.

Furthermore, along with a predetermined key operation on the key input unit 26,
The CPU 21 sets the feed amount of the vertical feed dogs 6, 4 and causes the display unit 27 to display the data corresponding to them.

Further, in the CPU 21, a needle position detecting device 28 for detecting the vertical position of the needle 3, a lower feed amount detecting device 29 for detecting the feed amount of the lower feed tooth 4, and a starting pedal 30 are connected via an input / output interface 31. And the upper feed changing device 7, the sewing machine motor 32 are connected via the drive circuit 33, the motor drive circuit 34 and the input / output interface 31, and a drive or stop signal is output from the CPU 21 to them. It

Then, during the sewing operation, the CPU 21 compares the pattern detection signals from the upper and lower cloth sensors 8 and 9 at every predetermined timing based on the detection signal of the needle position detecting device 28, and the upper work cloth corresponding to the deviation of the pattern. The feed change amount of W1 in the cloth feed direction is calculated, and a correction drive signal is output to the upper feed change device 7. or,
When the edge detection signal shown in FIG. 6 is input from both sensors 8 or 9 or from one of the predetermined sensors, the CPU 21 determines from the end of both work cloths W1 and W2 or from the predetermined one. The number of stitches S from the end of one of the work cloths corresponding to the other sensor to the needle drop point, the distance y between the detection centers of both sensors 8 and 9 and the needle drop point, and a key input in advance. Based on the feed pitch p of the prepared lower work cloth W2, calculation is performed according to the equation S = y / p.

Next, the operation of the sewing machine configured as described above will be described.

Now, as shown in FIG. 5, when the pattern matching mode is set by a predetermined key operation on the key input section 26 prior to the sewing operation of the sewing machine, the determination result of step 41 becomes YES, and the CPU 21 In the next step 42, the pattern matching mode is set. Next, when the start pedal 30 is operated in step 43, the sewing machine is operated in step 44. During operation of this sewing machine, the cooperation of the lower feed dog 4 and the presser foot 5
The upper and lower work cloths W1 and W2 are fed, and the upper feed dog 6 additionally feeds the upper work cloth W1. Then, in step 45, the pattern detection signals output from the upper and lower cloth sensors 8 and 9 are compared. Here, if there is a pattern deviation, the determination result of step 45 becomes YES, and step 46
Go to the pattern matching subroutine. Then, after the deviation amount of the upper work cloth W1 in the cloth feeding direction is calculated, the upper feed change amount is calculated based on the deviation amount, and the upper feed changing device 7 is corrected and driven based on the calculation result. To be done.

After the processing of step 46 is finished, and when the determination result of step 45 is NO, the process proceeds to step 47, and it is determined whether or not both work cloths W1 and W2 have passed between both sensors 8 and 9. Is
When the result is NO, the process returns to step 44 and steps 44 to 46 are repeated.

On the other hand, when the determination result of step 47 is YES, that is, when the edge detection signal shown in FIG. 6 is input to the CPU 21, step 48
The number of stitches calculation subroutine is performed, the number of stitches from the end detection position to the needle drop point is calculated based on the above formula, and based on the calculation result, the sewing machine is operated in the next step 49 and then stopped. It

On the other hand, if the determination result in step 41 is NO, in this embodiment, the process proceeds to step 50, and the cloth edge stop dedicated mode is set. When the start pedal 30 is operated in this mode setting state and the start pedal 30 is operated, the CPU 21 drives the sewing machine in step 52. Then, as in step 47, after the edge detection signal is input to the CPU 21 in step 53, the processing in steps 48 and 49 described above is executed, and sewing to the cloth edge is executed.

As described above, in this embodiment, if the pattern matching mode is set, the patterns of the two work cloths W1 and W2 can be sewn together while the work cloths W1 and W2 are accurately matched, and the work cloths W1 and W2 can be reliably joined at the end portions thereof. The sewing can be finished.
Further, by setting the cloth edge stop dedicated mode, it is possible to reliably perform the sewing accompanied by the cloth edge stop operation. Furthermore, in this embodiment, the sensors 8 and 9 for pattern matching can also detect the ends of the work cloths W1 and W2. It is possible to add a new function to the conventional sewing machine without the need for

The present invention is not limited to the above embodiment, but can be embodied in the following modes. That is, (a) a moving device for relatively moving both upper and lower work cloths in a direction intersecting the cloth feed direction is provided in order to perform pattern matching sewing of work cloths having various patterns including diagonal stripes and lattice stripes, When there is a pattern shift in a direction intersecting the cloth feed direction, the moving device is operated to perform pattern matching.

(B) The position of the lower work cloth W2 is moved relative to the upper work cloth W1.

(C) To be able to set a mode in which only pattern matching is performed.

(D) When the pattern matching mode is set, after the cloth edge is detected, the sewing machine is immediately driven at a low speed as shown in FIG.
Perform cloth edge stop control while performing pattern matching control for each needle.

EFFECTS OF THE INVENTION As described in detail above, according to the present invention, when a new function of automatically stopping the sewing machine at the sewing end position is added to the handle sewing machine having the conventional structure, a sensor dedicated to the cloth edge detection is specially provided. It has an excellent effect that it can be manufactured at low cost without the need.

[Brief description of drawings]

FIG. 1 is a perspective view showing a main part of a sewing machine embodying the present invention, FIG. 2 is a side sectional view of the same, FIG. 3 is an enlarged view showing a detection part of each sensor, and FIG. 4 is an electrical view of the sewing machine. FIG. 5 is a block diagram showing the configuration, FIG. 5 is a flowchart, FIG. 6 is an explanatory diagram showing an output signal of the sensor, and FIG. 7 is a flowchart in another example. In the figure, 8 is an upper cloth sensor, 9 is a lower cloth sensor (the above 8,
The detecting device is constituted by 9), 21 is a CPU constituting a control device, W1 is an upper work cloth, and W2 is a lower work cloth.

Claims (1)

[Claims] 1. Upper and lower work cloths (W1, W) superposed and arranged.
2) A detection device (8, 9) for detecting the pattern is provided. Based on the pattern detection signal from the detection device (8, 9), while changing the cloth feed amount for at least one of the work cloths, both In a pattern-matching sewing machine in which the patterns of the work cloths (W1, W2) are sewn together, the detection device (8, 9) is arranged on the cloth feeding side from the needle drop point, and the work cloth end portion A cloth edge, which is configured to output an edge detection signal when the edge of the cloth passes and which is provided with a control device (21) for controlling the operation of the sewing machine in accordance with the output of the edge detection signal. Pattern matching sewing machine with a detection function.