JPS6096459A - Sewn seam mask preventor for printing machine - Google Patents

Abstract

PURPOSE:To prevent possible defective fabric checking the generation of any sewn seam mark by providing a sensor for detecting the seam of fabric on a conveying belt ahead of the first screen by a specified repeat length to stop the squeegeeing of the screen positioned at the seam point tracking the seam of the fabric passing through a printing line. CONSTITUTION:When the seam 2 of a fabric 1 is detected with sensors 8 and 8, counters C are cleared and when the seam 2 enters the area (a) and a conveying belt 6 stops, the counters C turn to ''1''. Then, as the conveying belt 6 is fed by one repeat length P, the seam 2 advances to the position of a first screen 51 and with the counters C turning to ''2'', the first preset counter 71 outputs a signal S1 to keep the squeegee 61 of the screen 51 out of action. Thereafter, the same operation is performed and the aqueegee of the screen positioned facing the seam 2 is stopped sequentially and after the seam 2 passes, the operation will be restarted.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for preventing dyeing defects caused by adhesion of printing paste on the back of the screen that occurs when sewing seams in a flat screen printing machine, that is, seam portions of fabric are printed. It is.

In an automatic screen printing machine that uses a flat screen, a hot-edge belt for supporting and conveying the material to be printed, such as cloth, is intermittently fed, and while the belt is stopped, the screen is lowered onto the material to be printed, and then a squeegee is The printing paste is oozed out onto the material to be printed by scanning the screen on the screen, and after the screen and squeegee are raised, the printing operation is performed by intermittently feeding the conveyor belt again.

In such printing operations, if the sewing machine seam of the fabric to be printed is between the screen and the conveyor belt, when the screen is brought into contact with the top surface and the squeegee is scanned, the printing paste will be discharged from the screen. The paste did not bleed out evenly, and there was a perforation-like glue deposit on the back of the screen, and as shown in Figure 1, the marks of seam 2 were left on 2 to 6 yards of fabric 1 until it disappeared, as shown in Figure 1.・3 occurs and dyeing defects occur.

Normally, fabric has one seam every 50 yards (l), and the standard length of a product is 25 yards (1 roll); anything shorter than this will result in a short yardage product and all 1 roll will be defective. Traditionally, when weaving, a certain amount of leeway was given to the length of one strip of fabric to take into consideration the yield rate in the dyeing process, but as fabrics become more sophisticated and resource conservation increases, Due to the demands of manufacturers, it has become difficult to provide such a margin, and for this reason, if a seam mark on the sewing machine occurs between 2 and 6 yarns due to the adhesion of glue at the seam, one unit of fabric will be defective. A problem has started to arise where opposition continues to occur.

This invention was made in view of these circumstances.
The purpose of this system is to track the seam of fabric passing through the printing line and stop the screen squeegee at the seam, thereby preventing the occurrence of sewing machine seam marks and the generation of defective fabric. It has been done.

That is, the sewing machine seam prevention device of the textile printing machine of the present invention detects the seam of the fabric on the conveyor belt a predetermined repeat length ahead of the first screen of the textile printing line, which has the conveyor belt that rotates intermittently at a predetermined repeat length. A sensor is installed,
The method is characterized in that the number of repetitions of the conveyor belt after the detection signal is emitted from the seam detection sensor is counted, and a stop command is sequentially given to the squeegees of the screen arranged along the conveyor belt.

Next, further explanation will be given based on the embodiments shown in FIGS. 2 to 5. Figure 2 is a perspective view of the main parts of the printing line, where 1 is the fabric, 4 and 5 are fabric supply rollers, 6 is a conveyor belt, and 7 is a perspective view of the main parts of the printing line.
are the rollers around which the belt 6 is wound, 51, 52... are the screens, 61, 62... are the squeegees, 2 is the seam of the fabric, 8, 8 is an electromagnetic displacement detection sensor, 9 is the roller A pulse encoder detects the rotational movement, and P is the repeat length of the printing line.

The displacement detection sensors 8, 8 are in contact with the fabric 2 on the conveyor belt 6 at a position one repeat length ahead of the first screen 51, and issue an output signal when the seam 2 passes through this position. The reason why two sensors 8 are provided is to use the AND output of both sensors 8, 8 as a seam detection signal to avoid malfunctions caused by sensor 8 being activated due to wrinkles in the fabric 1, etc.

FIG. 4 is a diagram showing the control system of the textile printing line.

Preset counters 71 to 7N are essentially composed of a setter A1 counter C and a matching circuit B, and i preset counters are provided on one screen. That is, the preset counter 71 controls the operation of the squeegee on the first screen 51, the preset counter 72 controls the operation of the squeegee on the second screen 52, and in the same manner, the preset counter 7N controls the operation of the squeegee on the aINth screen. Side fence the operation of the 5N screen. And the setting device of the preset counter 71 has 1/
2, and the setting device of the preset counter 72 has 2/2.
Similarly, set the preset counter 7N to N.
/2 is given as the setting value. Here, N is the number of screens arranged on the textile printing line, and the matching circuit B is configured to continue generating output pulses while the content of the counter C is the same value as the setting value of the setting device A. be done. The signal from the encoder 9 mentioned above is applied to the counter C via the sending pulse generator 10. The feed pulse generator 10 is configured to generate one output pulse when the roller 7 rotates by a predetermined rotation angle, that is, every time the intermittent feeding operation of the conveyor belt 6 ends. Reference numeral 11 denotes an AND circuit, and the detection signals of the sensors 8, 8 are passed through the AND circuit 11 and given to each of the preset counters 51 to 5N as a clear signal.

Figure 3 shows the fifth screen (J is 1 to N) 5J.
8J is a relay solenoid that turns on and off the squeegee drive motor, 9J is a manual contact for selecting whether to use the screen 5J, and 10 is a sequence circuit that operates the squeegee.
J is a contact point for giving the operation timing of the squeegee. 11J is a b contact that is opened and closed by the signal from the preset counter 7J in FIG.
The contact 11J is opened when an output pulse is applied from the contact point 11J.

In the above configuration, when the seam 2 (Fig. 2) of the fabric 1 is detected by the sensors 8, 8, each counter C is cleared by the seam detection signal, and the seam 2 enters the area a in Fig. 2. When the conveyor belt 6 stops, the counter C becomes 1.
becomes. Next, when the conveyor belt 6 is fed one repeat length, the seam 2 advances to the position of the first screen 51, and when the conveyor belt 6 stops, the counter C becomes 2 and a signal is output from the first preset counter 51. S1 is output. Then, the contact 11J'('J is l) inserted into the sequence circuit for driving the squeegee of the first screen is opened, and the squeegee 61 of the screen 51 does not operate in the subsequent printing cycle. When the conveyor belt 6 is further fed by one repeat length, the seam 2 advances to the area b in FIG. Then, the squeegee 61 of the screen 51 also starts operating again. When the conveyor belt 6 is repeated one more time, the seam 2 advances to the position of the second screen 52,
When the loose belt 6 stops, the counter C becomes 4,
An output signal is generated from the preset counter 72 and the second
The contact 11J (J is 2) of the sequence circuit for the squeegee 62 of the screen 52 is opened, and in the subsequent printing cycle, the squeegee 62 of the screen 52
doesn't work. Thereafter, in the same manner, the screen squeegee at the position facing seam 2 is sequentially stopped, and seam 2
It will start working again after passing.

FIG. 5 shows that a 2.times.N bit shift register 12 can be used in place of the preset counters 7E to 7N in FIG. 4, and 13 is an output latch circuit. That is, when a seam detection signal is output from the sensor 8°8 via the AND circuit 11, the output of the latch circuit 13 becomes 1, and when a feed signal is output from the encoder 9 via the feed pulse generator 10, a shift occurs. The first bit of register 12 becomes 1, and latch circuit 13 is cleared. Then, when the second feed signal is issued and the seam 2 reaches the position of the first screen, the shift register 12
The signal 1 is shifted to the second bit, and the signal S1 becomes 1 to stop the squeegee on the first screen. Thereafter, each time a feed pulse is output, the signal 1 is shifted by 1 bit, thereby making it possible to stop the squeegee on the screen facing the seam as the seam progresses.

The setting position of the seam detection sensor 8 is generally one repeat length ahead of the first squeegee, but the squeegee can be stopped by a similar control system even if it is set two repeat lengths forward, three repeat lengths forward, etc. .

As described above, the present invention detects the perforation seam of the fabric to be printed with a screen printing machine and tracks the movement of this seam, thereby stopping the squeegee on the screen facing the seam and moving the squeegee over the seam. Since this is designed to prevent the local adhesion of printing paste that occurs when the printing paste operates, there is no risk of seam marks appearing on the fabric after the seam has passed, and dyeing due to the occurrence of seam marks is completely eliminated. The occurrence of defects can be completely prevented. In addition, a seam detection sensor is installed at a predetermined repeat length (1 repeat or several repeat length) in front of the first squeegee on the textile printing line to detect the seam of the fabric on the conveyor belt. This has the effect that the moving position can be accurately tracked and the control system can be simplified.

[Brief explanation of the drawing]

FIG. 1 is a diagram schematically showing the state in which seam marks occur after sewing machine seams in fabric. Figures 2 to 5 are diagrams showing an embodiment of the present invention, with Figure 2 being a perspective view of the main parts, Figure 3 being a diagram showing sequence lines for driving the squeegee of each screen, and Figure 4 being a diagram showing an embodiment of the present invention. 5 is a block diagram showing a control system, and FIG. 5 is a block diagram showing another embodiment of the control system. In the figure, 1 is cloth, 2 is a seam, 6 is a conveyor belt, 8 is a displacement detection sensor, 9 is a pulse encoder, 10 is a feed pulse generator, 121 is a shift register, 13 is a latch circuit, 5
'1.52...+ask Inon, 61.62...
... is a squeegee, 71.72...7N is a preset counter, P&l repeat length, A-setting device, mouth is a coincidence circuit, C is a counter, 11'J+ is a control contact, Sl...
...SN is a control signal. Agent Patent Attorney i! ! ! Takao Figure 1 Figure 4

Claims (1)

[Claims] (1) A sensor for detecting the seam of the fabric on the high-speed belt is provided in front of the first screen of the textile printing line having a conveyor belt that rotates intermittently at a predetermined repeat length, and this seam detection sensor A sewing machine seam prevention device for a flat screen textile printing machine, characterized by counting the number of repeats on the conveyor belt after a detection signal is issued from the conveyor belt and sequentially giving a stop command to the squeegees of the screen arranged on the conveyor belt. . A sewing machine seam mark prevention device according to claim 1.