JPH0976373A - Bag cutting device of bag making machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To cut a continuous bag correctly at the middle position of a punched hole during the stop of continuous bag feeding by a method in which before the stop of continuous bag feeding, the form of its light transmission region is read as image data, the set position of the light transmission region at the stop of continuous bag feeding and the positional dislocation of the blade of a cutter are calculated and corrected. SOLUTION: Before the stop of continuous bag feeding, in a range R from the set position X0 of its punched hole 2 to a cutter 3, the form of the hole 2 is read as image data. Next, the amount L of continuous bag feeding from image reading to the stop of continuous bag feeding is compared with the distance D1+D2 between the set position X1 of the hole 2 at image data reading and the position X0 of the blade of the cutter 3, and the dislocation L-(D1+D2) between the set position X0 of the hole 2 at the stop of continuous bag feeding and the position X1 of the blade of the cutter 3 is calculated. Besides, the dislocation L-(D1+D2) between the set position of the hole 2 at the stop of continuous bag feeding and the position X1 of the blade of the cutter 3 is corrected by a computer 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bag cutting device for a bag making machine.

[0002]

2. Description of the Related Art In a bag-making machine for producing plastic bags, a vertical sealer and a horizontal sealer usually vertically and horizontally seal a plastic film to form a vertical seal portion and a horizontal seal portion. . This produces a continuous bag, which is intermittently fed along its length and, at the central position of the longitudinal seal, the continuous bag is slit parallel to its feed direction. Further, when the feeding of the continuous bag is stopped, the continuous bag is cut at a right angle in the feeding direction by the cutter at the central position of the lateral seal portion. Therefore, bags of a certain size are sequentially and continuously manufactured. A hole may be formed at the intersection of the vertical seal portion and the horizontal seal portion, and the continuous bag may be slit parallel to the feed direction and cut at a right angle to the feed direction at the center position of the hole. In this case, when the continuous bag is cut at a right angle to the feeding direction, it is required to cut the continuous bag accurately at the center position of the punch hole.

Before cutting the present application, the applicant has developed and proposed a new type of device for cutting a continuous bag having a punched hole at a right angle to the feeding direction. That is what is described in Registered Utility Model No. 3009204. In the device of the publication, a light source is arranged upstream of the cutter below the feeding path of the continuous bag, and light is emitted toward the continuous bag. Furthermore, the video camera is arranged to face the light source above the continuous bag feeding path,
Before the feeding of the continuous bag is stopped, the video camera receives the light transmitted through the hole, and the shape of the hole is read as image data in the range from the center position of the hole to the upstream end. Further, based on the image data, the computer calculates the distance between the center position of the punched hole and its upstream end. After that, when the feeding of the continuous bag is stopped, the video camera receives the light transmitted through the hole, and the shape of the hole is read as image data at the upstream end of the hole.
Based on the image data, the computer calculates the distance between the upstream end of the punch hole and the position of the cutter blade when the continuous bag feed is stopped, and compares it with the distance between the center position of the punch hole and its upstream end. Thus, the deviation between the central position of the punched hole and the position of the cutter blade when the continuous bag is stopped is calculated. After that, based on the output signal of the computer,
The cutter is moved by the cutter moving mechanism, and the cutter moves in parallel with the feeding direction of the continuous bag. This corrects the deviation between the central position of the punched hole and the position of the cutter blade when the continuous bag feed is stopped. Therefore, the continuous bag can be accurately cut at the central position of the punch hole.

However, this device is not efficient because the shape of the punched hole must be read twice before and after the continuous bag is stopped. further,
Regardless of before the continuous bag feed is stopped, when the continuous bag feed is stopped,
The punch hole reaches the position of the cutter blade. Therefore, when the shape of the hole is read by the video camera, the cutter obstructs the shape of the hole, and the shape of the hole cannot always be read. In particular, when the continuous bag has a small hole, the entire hole may be hidden by the cutter, and the shape of the hole may not be readable by the video camera. Therefore, this device cannot correct the deviation between the central position of the punching hole and the position of the blade of the cutter when the continuous bag feeding is stopped, and the continuous bag can be accurately cut at the central position of the punching hole. There is a problem that you cannot do it.

[0005]

It is an object of the present invention to intermittently feed a continuous bag made of a plastic film having a light transmitting area such as a punched hole in its length direction, and to preset the light transmitting area when the continuous bag is stopped from feeding. At the set position, the cutter cuts the continuous bag at a right angle to the feeding direction, and when successively manufacturing bags of a certain size, before the continuous bag feeding is stopped, the shape of the light transmission area is used as image data. Just by reading, the deviation between the setting position of the light transmission area and the position of the cutter blade when the continuous bag feeding is stopped is calculated,
The purpose of the correction is to eliminate the need to read the shape of the light transmission area as image data when the continuous bag is stopped from being fed.

[0006]

According to the present invention, the light source is disposed on the upstream side of the cutter on one side of the continuous bag feeding path, and the light is irradiated toward the continuous bag and the cutter, and the other side of the continuous bag feeding path is provided. At, the detector is positioned opposite the light source. Then, before stopping the feeding of the continuous bag, the light-transmitting area of the continuous bag reaches the position of the light source, the light of the light source passes through the light-transmitting area, and a part of the light is blocked by the cutter. Upon receiving the light transmitted through the light transmitting area, the shape of the light transmitting area is read as image data at least in the range from the setting position of the light transmitting area to the cutter. Further, a computer is connected to the detector, and based on the image data of the detector, the computer calculates the distance between the set position of the light transmission area and the position of the blade of the cutter when reading the image data. In addition, the computer measures the amount of continuous bag feeding from the time when the image data is read to when the continuous bag is stopped, and the amount of the feed is between the light transmission area setting position and the cutter blade position when reading the image data. The distance between the set position of the light transmission region and the position of the cutter blade when the continuous bag is stopped is calculated. The computer may be made to recognize in advance about the amount of continuous bag feeding from the time when the image data is read to when the continuous bag feeding is stopped. further,
The cutter moving mechanism is connected to the computer, and in response to the output signal of the computer, the cutter moving mechanism operates the cutter, and the cutter moves in parallel to the continuous bag feeding direction, which causes light transmission when the continuous bag feeding is stopped. The deviation between the set position of the area and the position of the cutter blade is corrected.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below.

In FIG. 1, this is a bag cutting device of a bag making machine, in which a vertical seal portion and a horizontal seal portion are formed in a plastic film, whereby a continuous bag 1 is manufactured, and the continuous bag 1 has its longitudinal direction. It is the same as that described in Registered Utility Model No. 3009204. Further, a punch hole 2 is formed in the lateral seal portion, and as shown in FIG. 2, the continuous bag 1 is slit in parallel with the feed direction X at the center position of the punch hole 2. The punched hole 2 is rectangular and has an upstream edge A, a central edge B and a downstream edge C. Therefore,
At the upstream edge A and the downstream edge C of the punched hole 2,
The continuous bag 1 is slit in parallel with the feeding direction X, and the slit position S of the continuous bag 1 is formed by this.

Further, when the continuous bag 1 is stopped to be fed, the punched hole 2
At the preset setting position X0, the cutter 3 cuts the continuous bag 1 at a right angle to the feeding direction X. In this embodiment, the central position of the punched hole 2, that is, the central edge B is selected as the set position X0, and the continuous bag 1 is cut at a right angle to the feeding direction X at the central edge B of the punched hole 2. Therefore, bags of a certain size are successively manufactured, and the punched holes 2 form four corners of the bag.

Further, the light source 4 is arranged upstream of the cutter 3 below the feeding path of the continuous bag 1 so that light is emitted toward the continuous bag 1 and the cutter 3. further,
A video camera 5 is used as a detector, and the video camera 5 is arranged above the feeding path of the continuous bag 1 so as to face the light source 4. The video camera 5 has a constant reading range R, has an electronic shutter, receives light transmitted through the hole 2, and reads the shape of the hole 2.

Further, the computer 6 is a video camera 5
The cutter moving mechanism is connected to the computer 6. The cutter moving mechanism is for correcting the deviation between the set position X0 of the punched hole 2 and the position X1 of the blade of the cutter 3, and is composed of a servo motor 7, a feed screw 8 and a nut 9, and the servo motor 7 is connected to the computer 6. The feed screw 8 extends parallel to the feeding direction X of the continuous bag 1 and is transmission-coupled to the servomotor 7. Cutter 3 is frame 10
The nut 9 is screwed onto the feed screw 8 and fixed to the frame 10.

In this device, before the continuous bag 1 is stopped to be fed, when the feeding speed is considerably reduced, a predetermined distance L (about 8 mm) before the continuous bag 1 is stopped,
The hole 2 of the continuous bag 1 reaches the position of the light source 4, the light of the light source 4 is emitted toward the continuous bag 1 and the cutter 3, passes through the hole 2 of the continuous bag 1, and is cut by the cutter 3. The section is shut off. Further, when the light of the light source 4 is transmitted through the hole 2 of the continuous bag 1 and a part of the light is blocked by the cutter 3, the video camera 5 receives the light transmitted through the hole 2 and the electronic shutter is operated. It operates instantaneously, and the shape of the punched hole 2 is read as image data in at least the range R from the set position X0 of the punched hole 2 to the cutter 3. 1 and 2 show the state.

Further, based on the image data of the video camera 5, the setting position X0 of the punched hole 2 and the side position X of the cutter 3 when the computer 6 reads the image data.
The distance D1 between the two is calculated. Furthermore, the calculated value D1
Is added with the distance D2 between the side surface position X2 of the cutter 3 and the blade position X1 thereof, whereby the set position X0 of the punched hole 2 and the position X1 of the blade of the cutter 3 at the time of reading image data are added.
The distance D1 + D2 between them is calculated. Regarding the distance D2 between the position X2 on the side surface of the cutter 3 and the position X1 of the blade, the computer 6 may be made to recognize it in advance.

Further, after reading the image data, for example, a motor for feeding the continuous bag 1 produces a pulse, which is sent to the computer 6, and based on the number of the pulses,
The computer 6 measures the feed amount L of the continuous bag 1 from the time of image reading to the stop of the continuous bag 1 feeding. Further, the feed amount L is a distance D between the set position X1 of the punched hole 2 and the position X0 of the blade of the cutter 3 when reading the image data.
1 + D2, whereby the set position X0 of the punched hole 2 and the position X1 of the blade of the cutter 3 at the time of stopping the feeding of the continuous bag 1
Deviation L- (D1 + D2) is calculated.

Further, the servo motor 7 is driven by the computer 6, and in response to the output signal of the computer 6, the feed screw 8 is rotated by the servo motor 7 and the feed screw 8 acts on the nut 9. Therefore, the feed screw 8
The cutter 3 and the frame 10 are operated by the nut 9 and the cutter 3 and the frame 10 move in parallel to the feeding direction X of the continuous bag 1. This corrects the deviation L- (D1 + D2) between the set position X0 of the punched hole 2 and the position X1 of the blade of the cutter 3 when the feeding of the continuous bag 1 is stopped.

After that, the cutter 3 cuts the continuous bag 1 at right angles to the feeding direction X thereof. Therefore, the hole 2
At the set position X0 of, that is, the central edge B,
The continuous bag 1 is cut accurately.

Therefore, in the case of this apparatus, before the feeding of the continuous bag 1 is stopped, only the shape of the punched hole 2 is read as image data, whereby the set position X0 of the punched hole 2 when the feeding of the continuous bag 1 is stopped is obtained. The deviation L- (D1 + D2) of the position X1 of the blade of the cutter 3 can be calculated. Continuous bag 1
It is efficient since it is not necessary to read the shape of the punched hole 2 as image data when the feeding of the sheet is stopped. Furthermore, continuous bag 1
Even if the hole 2 is small, the shape of the hole 2 is read before the feeding of the continuous bag 1 is stopped and before the blade position X1 of the cutter 3 is reached. Therefore, when the shape of the hole 2 is read by the video camera 5, the cutter 3
There is no problem that it is blocked by. Therefore, regardless of the size of the punched hole 2, the set position X0 of the punched hole 2 and the position X0 of the blade of the cutter 3 when the feeding of the continuous bag 1 is stopped.
The deviation L- (D1 + D2) can be calculated and corrected without any trouble, and the continuous bag 1 can be accurately cut at the set position X0 of the punched hole 2.

In the case of a transparent plastic film, light passes through the continuous bag 1 itself and it is difficult to read the shape of the punched hole 2 as image data. Based on this, as shown in FIG. 3, polarizing filters 11 and 12 are provided on both sides of the continuous bag 1, the light source 4 and the video camera 5 are covered with the polarizing filters 11 and 12, and the polarizing filters 11 and 12 are mutually attached. You may arrange | position so that it may have a right angle direction. In this case, the light passing through the hole 2 is polarized by the polarization filter 11 of the light source 4 and is polarized by the polarization filter 12 of the video camera 5 in the direction perpendicular to the plane of polarization. Therefore, the light does not pass through the polarization filter 12 and does not reach the video camera 5. On the other hand, the light passing through the continuous bag 1 itself is polarized by the polarization filter 11 of the light source 4, but when the light passes through the continuous bag 1 itself, the polarization plane of the light is rotated by the continuous bag 1. . Therefore, the light is only polarized by the polarization filter 12 in a direction other than the direction perpendicular to the plane of polarization, and the light passes through the polarization filter 12 and reaches the video camera 5. Therefore, the shape of the punched hole 2 can be clearly read.

In the above embodiment, the computer 6 measures the feed amount L of the continuous bag 1 from the time when the image data is read to when the continuous bag 1 is stopped. The feed amount L may be recognized. In this case, it is not necessary to measure the feed amount L of the continuous bag 1, and after the image data is read, before the feed of the continuous bag 1 is stopped, immediately after the feed of the continuous bag 1 is stopped, the set position X0 of the punched hole 2 and the cutter 3 are cut. Deviation of blade position X1 L- (D
1 + D2) can be calculated and corrected, which can speed up the control of the device.

Regarding the positions of the light source 4 and the video camera 5, on the contrary, the light source 4 is arranged upstream of the cutter 3 on the upper side of the feeding path of the continuous bag 1, and the video is placed on the lower side of the feeding path of the continuous bag 1. The camera 5 may be arranged so as to face the light source 4. It is also conceivable to use something other than the video camera 5 as a detector and read the shape of the punched hole 2 by using it. Not only the hole 2 of the continuous bag 1 but also the shape of a light transmitting region such as a corner cut portion can be read as image data, and the continuous bag 1 can be cut accurately at the preset setting position.

[0021]

As described above, according to the present invention, before the feeding of the continuous bag 1 is stopped, the shape of the light transmitting region thereof is simply read as image data, whereby the continuous bag 1 is read.
It is possible to calculate the deviation L- (D1 + D2) between the set position X0 of the light transmission area and the position X1 of the blade of the cutter 3 when the feeding of the is stopped. It is efficient since it is not necessary to read the shape of the light transmission area as image data when the continuous bag 1 is stopped being fed. Further, even if the light-transmitting area of the continuous bag 1 is small, the shape of the light-transmitting area is read before the feeding of the continuous bag 1 is stopped and before the blade position X1 of the cutter 3 is reached. Therefore, when the shape of the light transmission area is read by the detector such as the video camera 5, there is no problem that the cutter 3 obstructs the shape. Therefore, irrespective of the size of the light transmission area, the deviation L- (D1 + D2) between the setting position X0 of the light transmission area and the blade position X1 of the cutter 3 when the continuous bag 1 is stopped is calculated and corrected without any trouble. The continuous bag 1 can be accurately cut at the set position X0 of the light transmission region, and the intended purpose can be achieved.

[Brief description of drawings]

FIG. 1 is a side view showing an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a reading range of the video camera of FIG.

FIG. 3 is a side view showing another embodiment.

[Explanation of symbols]

 1 continuous bag 2 punched hole 3 cutter 4 light source 5 video camera 6 computer 7 servo motor 8 feed screw

Claims (1)

[Claims] 1. A continuous bag made of a plastic film having a light-transmitting region such as a punched hole is intermittently fed in its length direction, and when the continuous bag is stopped from feeding, a preset position of the light-transmitting region is set. In the bag-making machine, wherein the continuous bag is cut at a right angle to the feeding direction by a cutter so as to successively and successively produce bags of a certain size, in one side of the continuous bag feeding path, the cutter Of the light source for irradiating light toward the continuous bag and the cutter, on the other side of the continuous bag feed path, arranged to face the light source, before the continuous bag is stopped, When the light transmission region reaches the position of the light source, the light of the light source transmits the light transmission region, and the light is transmitted through the light transmission region when a part of the light is blocked by the cutter. Receiving, at least in the range from the setting position to the cutter, a detector that reads the shape of the light transmission region as image data, and is connected to the detector, based on the image data, when reading the image data The distance between the set position and the position of the blade of the cutter is calculated, and the feeding amount of the continuous bag from the time of reading the image data to the time of stopping the feeding of the continuous bag is measured or recognized, and the image is transferred to the image. A computer that compares the set position when reading data and the distance between the positions of the blades of the cutter, thereby calculating a deviation between the position of the set blades and the position of the cutter blades when the continuous bag is stopped from feeding, Connected to the computer, in response to the output signal of the computer, the cutter is moved in parallel to the feeding direction of the continuous bag, A bag cutting device for a bag making machine, comprising: a cutter moving mechanism that corrects a deviation between the set position and the position of the cutter blade when the bag is stopped to be fed.