JP2013166584A - Mechanism for detecting stuck foreign matter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mechanism for detecting a stuck foreign matter, configured to detect a foreign matter stuck between seal bars.SOLUTION: In a rotary filling-packaging machine, paired seal bars each having a fixed seal bar, a movable arm, and a movable seal bar, are installed on a rotary table, and the paired seal bars convey a base material film along with the rotation of the rotary table while sealing the long base material film folded half. A mechanism for detecting a stuck foreign matter in the rotary filling-packaging machine is equipped with: a laser displacement sensor for measuring a distance value between a measurement plane which is provided on the face opposite the sealing face of the movable seal bar and a measurement plane when the paired seal bars are closed completely; and a calculation/control part which receives the distance value output by the laser displacement sensor, calculates a difference in the distance value between the previous turn and the current turn of the same paired seal bars, and determines whether a foreign matter has been stuck in the paired seal bars.

Description

  The present invention is a method for biting foreign matter in a rotary filling and packaging machine equipped with a sealing mechanism for performing thermocompression sealing with a plurality of seal bar pairs installed on a disc-shaped rotary table after folding a single film in half. Regarding detection.

FIG. 1 shows an example of a main part of a rotary filling and packaging machine. The film 101 which is a packaging material is unwound from a long roll state (not shown) and is half-folded with the upper part being vacated by the film guide 5.
The rotary table 6 has a plurality of seal bar pairs (having a fixed seal bar 1, a movable arm 2 and a movable seal bar 3) and a plurality of filling nozzles 7 for alternately filling the contents. Has been.

The half-folded film 101 is conveyed in the direction of the arrow A so as to go around the outer periphery along with the rotation of the rotary table 6. At this time, the film 101 is conveyed outside the fixed seal bar 1 and arranged so as to sandwich the filling nozzle 7 in a half-folded state.
Further, in the vicinity of the entrance of the film 101 of the rotary table 6, the movable arm 2 is in an open state, and the movable seal bar 3 attached to the movable arm 2 is separated from the fixed seal bar 1.

  Next, the movable arm 2 starts to move and the movable seal bar 3 moves to a position where the film 101 is sandwiched between the fixed seal bar 1 and the film 101 in a half-folded state between the movable seal bar 3 and the fixed seal bar 1. Is sealed by thermocompression bonding with a predetermined portion of. By repeating this, a bag-like portion having an open top is formed on the film 101.

Immediately after the seal bar pair sandwiches a predetermined portion of the film 101, the contents are supplied through the filling nozzle 7. The contents to be supplied are prepared in advance by weighing the content weighing mass table 8 by a predetermined amount, and the contents weighed from the content weighing mass table 8 at a predetermined timing are filled with the filling nozzle 7. Sent to.
In order to form a seal with sufficient strength, a predetermined length of time is required for sandwiching the film 101 between the pair of seal bars, so that the filling operation of the contents is performed while sealing between them. Thereafter, when the movable arm 2 is opened again, the seal bar pair is opened, and the filling nozzle 7 is pulled out from the bag-like portion, the upper portion of the film 101 is sealed. With the above, a product in which the contents are enclosed and packaged in a bag formed of the film 101 is completed. If this is cut appropriately, individual products are completed.

  In such a rotary filling and packaging machine, if foreign matter other than the film 101 is caught between the fixed seal bar 1 and the movable seal bar 3 constituting the seal bar pair, the thermocompression bonding becomes insufficient, and the seal Defects and insufficient seal strength occur. Therefore, a device for detecting whether foreign matter is caught between the fixed seal bar 1 and the movable seal bar 3 is required.

  For example, as described in Patent Document 1, a conventional foreign object biting detection device measures the amount of displacement by measuring the displacement of a movable seal bar using an eddy current displacement sensor. The difference from the circulation was obtained and compared with the threshold value to detect the biting of foreign matter.

  Further, as described in, for example, Patent Document 2, the lever principle is used to amplify the amount of change in the amount of displacement between the movable seal bar and the sensor when the foreign matter is bitten, thereby increasing the foreign matter detection accuracy. I was doing that.

JP 2005-162219 A JP 2007-106468 A

  When the eddy current type displacement sensor described in Patent Document 1 is used, it is necessary to make the distance between the sensor and the seal bar close to about 3 mm. In this case, when the heated seal bar is stopped in the vicinity of the sensor for a long time, there is a problem that the sensor becomes high temperature due to the radiant heat of the seal bar and breaks down.

  When the sensor is of a heat resistant specification, the distance between the sensor and the seal bar needs to be close to about 0.5 mm. In this case, there is a problem that the seal bar interferes with (contacts) the sensor when the seal bar bites in about 1 mm in size or due to thermal expansion of the seal bar.

  Although attempts have been made to increase the foreign matter detection accuracy using the lever principle described in Patent Document 2, there is a problem that the mechanism becomes complicated and is likely to break down.

In the invention according to claim 1 of the present invention, a plurality of seal bar pairs each having a fixed seal bar, a movable arm, and a movable seal bar are installed on a disk-shaped rotary table, and are attached to the movable arm. With the movable seal bar and the fixed seal bar, the base film is transported as the rotary table rotates while sandwiching and sealing a predetermined portion of the long base film that has been half-folded in advance. In rotary filling and packaging machines,
A measurement surface provided on a surface opposite to the seal surface of the movable seal bar;
A laser displacement sensor installed outside the rotary table and capable of measuring a distance between the seal bar pair and the measurement surface when the pair is completely closed;
The distance value output by the laser displacement sensor is received, the difference between the distance value between the previous rotation and the current rotation of the same seal bar pair is calculated, and it is determined from the difference whether the seal bar pair has caught a foreign object. Calculation / control section,
A foreign matter biting detection mechanism in a rotary filling and packaging machine.

  The invention according to claim 2 of the present invention is characterized in that the measurement surface has a cylindrical surface shape having the same curvature R as the locus of the measurement surface when the rotary table rotates. The described foreign object biting detection mechanism.

The invention according to claim 3 of the present invention has a measurement surface in which a reference seal bar pair, which is one of the plurality of seal bar pairs, reaches a position higher than the measurement surface of the other seal bar pairs. And
A circling sensor is disposed at a position where only the measurement surface of the reference seal bar pair can be detected,
The calculation / control unit detects a reference seal bar pair by receiving a signal output when the circumference sensor detects the measurement surface of the reference seal bar pair, and detects each of the other seal bar pairs. The foreign matter biting detection mechanism according to claim 1, wherein a seal bar number can be assigned.

In the invention according to claim 4 of the present invention, a plurality of seal bar pairs each having a fixed seal bar, a movable arm, and a movable seal bar are installed on a disk-shaped rotary table, and are attached to the movable arm. With the movable seal bar and the fixed seal bar, the base film is transported as the rotary table rotates while sandwiching and sealing a predetermined portion of the long base film that has been half-folded in advance. In rotary filling and packaging machines,
A measurement plate attached to the movable seal bar and having a measurement surface;
A laser displacement sensor installed outside the rotary table and capable of measuring a distance between the seal bar pair and the measurement surface when the pair is completely closed;
The distance value output by the laser displacement sensor is received, the difference between the distance value between the previous rotation and the current rotation of the same seal bar pair is calculated, and it is determined from the difference whether the seal bar pair has caught a foreign object. Calculation / control section,
In a rotary filling and packaging machine, comprising:

  In the invention according to claim 5 of the present invention, the measurement surface has a cylindrical surface shape having the same curvature R as the locus of the measurement surface when the rotary table rotates, or is equivalent to the curvature R. 5. The foreign object biting detection mechanism according to claim 4, wherein the foreign object biting detection mechanism has a planar shape with an inclination.

The invention according to claim 6 of the present invention is such that the measurement plate attached to a reference seal bar pair which is one of the plurality of seal bar pairs is attached to another seal bar pair. It has a measuring surface that is higher than the measuring surface of the plate,
A circling sensor is disposed at a position where only the measurement surface of the reference seal bar pair can be detected,
The calculation / control unit detects a reference seal bar pair by receiving a signal output when the circumference sensor detects the measurement surface of the reference seal bar pair, and detects each of the other seal bar pairs. A foreign matter biting detection mechanism according to any one of claims 4 to 5, wherein a seal bar number can be assigned.

  In the invention according to claim 7 of the present invention, only one pair of the plurality of seal bar pairs is different from the other seal bar pairs in the seal eyes formed on the seal surfaces of the fixed seal bar and the movable seal bar. The foreign object biting detection mechanism according to any one of claims 1 to 6, characterized in that it is configured as described above.

  In the invention according to claim 8 of the present invention, an irregular reflection preventing plate is disposed on a side surface of the movable seal bar so as to close a gap between the pair of adjacent seal bars, and the laser beam of the laser displacement sensor is 8. The foreign object biting detection mechanism according to claim 1, wherein the base film is prevented from being irradiated.

  The invention according to claim 9 of the present invention is characterized in that a distance value between the laser displacement sensor and a seal bar pair is an average value of a plurality of measurement values obtained when the seal bar pair passes. The foreign object biting detection mechanism according to any one of claims 1 to 8.

  According to the foreign matter biting detection mechanism of the present invention, since the distance between the laser displacement sensor and the seal bar can be increased, even when the heated seal bar stops at the front of the sensor, the influence of the radiant heat is small. Will not fail, and there is no risk of interference.

  Furthermore, since the distance to the movable seal bar is measured directly, or the distance is measured by attaching a measuring plate to the movable seal bar, the structure is simple and the mechanism is complicated. Can be prevented.

  Further, according to the present invention, the shape of the measurement surface is a cylindrical surface shape having the same curvature R as the trajectory of the measurement surface when the rotary table rotates, or has an inclination equivalent to the curvature R. Due to the planar shape, the influence on the measurement value due to the rotation of the rotary table can be reduced during the distance measurement by the laser displacement sensor, and the variation of the measurement value can be suppressed.

  In addition, according to the present invention, it is possible to assign a seal bar number to each seal bar by providing a circumference sensor that can identify a reference seal bar pair that is one of a plurality of seal bar pairs. Therefore, it is possible to know which seal bar is a seal bar that has bitten foreign matter, and the seal bar can be easily inspected.

  Further, according to the present invention, only one of the plurality of seal bar pairs is different in seal eyes formed on the seal surfaces of the fixed seal bar and the movable seal bar from the other seal bar pairs. Thus, when foreign matter is detected, it is possible to identify a defective portion even from the product.

  Further, according to the present invention, the irregular reflection preventing plate is installed on the side surface of the movable seal bar so as to close the gap between the pair of adjacent seal bars, and the laser beam of the laser displacement sensor is irradiated to the base film. By preventing this, irregular reflection of laser light by the base film can be prevented, and erroneous detection due to irregular reflection of laser light can be prevented.

  Furthermore, according to the present invention, the distance value between the laser displacement sensor and a certain seal bar pair is set to an average value of a plurality of measurement values obtained when the seal bar pair passes, whereby measurement with less error is performed. Is possible.

The perspective view which shows an example of the principal part of a rotary type filling and packaging machine. It is the schematic of a fixed seal bar, (a) Top view, (b) Side view. It is the schematic of a movable arm, (a) Top view, (b) Side view. It is the schematic of a movable seal bar, (a1) Top view of an example, (a2) Side view, (b1) Top view, (b2) Side view of another example. The side view which shows schematic structure of a seal bar pair. The figure which shows operation | movement of the movable arm with respect to a fixed seal bar, and a movable seal bar. Explanatory drawing of a pass line when a rotary table is seen from the upper surface. The side view which shows schematic structure of the seal bar pair used as a reference | standard. The top view explaining the outline | summary of installation of an irregular reflection prevention plate.

  The schematic configuration and operation of the main part of the rotary filling machine according to the present invention are as described above with reference to FIG.

  An embodiment of a foreign object biting detection apparatus according to the present invention will be described with reference to the drawings.

  As shown in FIG. 2, the fixed seal bar 1 has an L shape, and is pierced so that the cartridge heater 21 can be inserted. Further, a hole 20a into which a connection pin 20 (described later) can be inserted is formed so that the movable arm 2 (described later) can be connected. Furthermore, a hole (not shown) for fixing the bolt to the rotary table 6 is formed, and installation by fixing the bolt is possible.

  As shown in FIG. 3, the movable arm 2 has an L shape like the fixed seal bar 1, and a hole 20 b into which the connecting pin 20 can be inserted is formed so that the movable arm 2 can be connected to the fixed seal bar 1. A cam follower 22 is attached to one end of the movable arm 2, and the movable arm 2 is operated along the cam to perform a sealing operation. At the other end, a hole 23a for receiving a pin 23 (described later) for connecting the movable arm 2 and the movable seal bar 3 is formed. Furthermore, a plurality of holes are provided for receiving springs 24 for pressing the movable seal bar 3 against the fixed seal bar 1 when the sealing operation is performed.

An example of the movable seal bar is shown in FIGS. 4 (a1) and (a2).
The movable seal bar 3a has a cylindrical shape having a hole 33a that can accommodate the end of the movable arm 2 on the side where the hole 23a is located.
Further, the movable seal bar 3a is provided with a hole 23b in the side surface portion by a long hole, and the movable seal bar 3a is attached to the movable arm 2 by being connected to the hole 23a of the movable arm 2 by the pin 23. Can be done. When the movable arm 2 with the movable seal bar 3a attached comes to the sealing position, the spring 24 can be pressurized.

  Further, the displacement sensor measurement surface 30 on the back surface of the movable seal bar 3 has a cylindrical surface shape having a curvature R instead of a flat surface. The value of the curvature R is the same value as the curvature of the locus followed by the displacement sensor measurement surface 30 on the back surface of the movable seal bar 3 when the rotary table 8 rotates. Thereby, even if the displacement sensor measurement surface 30 rotates together with the rotary table 8, the distance between a displacement sensor 40 (described later) fixedly installed outside the rotary table 8 and the displacement sensor measurement surface 30 hardly changes. The influence of the rotation of the table 8 can be reduced.

Another example of the movable seal bar is shown in FIGS. 4 (b1) and (b2).
The movable seal bar 3b has a cylindrical shape having a groove 33b into which an end of the movable arm 2 on the side where the hole 23a is located can be fitted.
Further, the movable seal bar 3b has a hole 23b formed in the side surface portion as an elongated hole, and the movable seal bar 3b is attached to the movable arm 2 by being connected to the hole 23a of the movable arm 2 by the pin 23. Can be done. When the movable arm 2 with the movable seal bar 3b attached reaches the seal position, the spring 24 can be pressurized.

  A measuring plate 25 is attached to the movable seal bar 3b by bolting or welding, and a distance is measured using a displacement sensor measuring surface 31 facing a displacement sensor 40 (described later) of the measuring plate 25. It may be. The shape of the displacement sensor measurement surface 31 may be the curvature R of the locus followed by the displacement sensor measurement surface 31 when the rotary table 8 is rotated, or may be a plane having an inclination equivalent to the curvature R.

When the fixed seal bar 1, the movable arm 2, and the movable seal bar 3a are assembled, a pair of seal bars having a shape as shown in FIG. 5 is obtained. Here, although the case where the thing of the shape of 3a is used as a movable seal bar is demonstrated, even if it uses the movable seal bar 3b and the measurement plate 25, the same structure and operation | movement are possible.
The end of the movable arm 2 on the side where the hole 23a is located is accommodated in the hole 33a of the movable seal bar 3a, the hole 23a and the hole 23b are aligned, the pin 23 is passed, and the movable arm 2 and the movable seal bar 3a. Are concatenated.

  The spring 24 attached to the movable arm 2 functions to push the movable seal bar 3 a toward the fixed seal bar 1. Moreover, since the hole 23b is a long hole, the pin 23 can translate in the hole 23b. With such a structure, in the sealing operation, the spring 24 is pressed from the inside of the movable seal bar 3a, so that the movable seal bar 3a can be strongly pressed against the fixed seal bar 1.

  Further, the pin 20 is passed through the hole 20a of the fixed seal bar 1 and the hole 20b of the movable arm 2, and the movable arm 2 is connected to the fixed seal bar 1 so as to be rotatable.

An outline of the operation of the seal bar pair in FIG. 5 is shown in FIGS.
When the cam follower 22 installed at one end of the movable arm 2 follows a cam (not shown), the movable seal bar connected to the movable arm becomes a fixed seal bar as shown in FIGS. The operation to open and close is performed. (A) is a state in which a fixed seal bar and a movable seal bar are in contact (0 °), (b) is a state in which it is opened 30 °, (c) is in a state in which it is opened 60 °, and (d) is in a state where it is opened 90 °. State.

As shown in FIG. 7, the plurality of seal bar pairs are installed on the rotary table 6, and the cam follower 22 installed at one end of the movable arm 2 cams (not shown) as the rotary table 6 rotates in the direction of arrow A. Open and close while following.
In section 1, the seal bar pair is completely closed (FIG. 6A). In section 2, the seal bar pair opens, and in section 3, the seal bar pair is completely open (FIG. 6D). In section 4, the operation of closing the seal bar is performed.

  In the section 4 in FIG. 7, the film 101 half-folded by the film guide 5 is guided between the pair of seal bars that are about to be closed. Further, the film 101 is conveyed along the pass line 100 together with the rotation of the rotary table 6 while being sandwiched and sealed by a pair of completely closed seal bars in the section 1, and the contents are filled during this time. In section 2, the seal bar pair begins to open, and in section 3, it opens completely. In section 2 to section 3, the upper end of the film 101 is sealed and the contents are enclosed and packed, and the product is discharged from the rotary filling and packaging machine.

The displacement sensor 40 is disposed at a position facing the displacement sensor measurement surface 30 (or 31) in the section 1 where the seal bar pair is completely closed (see FIGS. 7 and 5).
At this time, if the closed state of the seal bar pair is incomplete due to biting of foreign matter, the displacement sensor measurement surface 30 (or 31) is placed on the displacement sensor 40 as compared to the normal state without foreign matter. It will be in the state which approached. Therefore, if the distance to the displacement sensor measurement surface 30 (or 31) is monitored by the displacement sensor 40, foreign object biting between the seal bar pair can be detected.

  Since the rotary table 6 is provided with a plurality of seal bar pairs, means for knowing which seal bar pair has an abnormality is also required. As one method for determining a pair of reference seal bars from among a plurality of seal bar pairs, there is a method of using a circumference sensor 41. The circulation sensor 41 is installed in the vicinity of the position immediately above the displacement sensor 40.

FIG. 8 shows an example of a reference seal bar pair, and FIG. 5 shows an example of other seal bar pairs.
In the reference seal bar pair (see FIG. 8), the movable seal bar 4 is made longer than the other movable seal bars 3, so that when it is assembled as a seal bar pair, the position is higher than the other seal bar pairs. The displacement sensor measurement surface 30 is present.

  The circling sensor 41 can detect the displacement sensor measurement surface 30 of the movable seal bar 4 when the reference seal bar pair (see FIG. 8) comes to the detection position. On the other hand, when the other seal bar pair (see FIG. 5) comes to the detection position, the displacement sensor measurement surface 30 of the movable seal bar 3 does not have a height to the installation position of the rotation sensor 41, so the rotation sensor 41 is displaced. The sensor measurement surface 30 cannot be detected.

  The calculation / control unit 42 receives the analog output of the displacement sensor 40 and the signal output of the revolution sensor 41. When the reference seal bar pair comes to the detection position, the calculation / control unit 42 detects it based on the signal from the rotation sensor 41 and records the displacement amount measured by the displacement sensor 40. When the other seal bar pair has reached the detection position, the number of the seal bar pair from the signal of the previous round sensor 41 and the displacement amount measured by the displacement sensor 40 are recorded.

  As another method for determining a reference seal bar pair from a plurality of seal bar pairs, there is a method using a rotary encoder. By installing a rotary encoder so as to synchronize with the rotation of the rotary table 6 and grasping the relationship between the rotation of the rotary table 6 and the number of pulses of the rotary encoder, the reference seal bar can be reliably detected. .

  If a standard seal bar pair can be detected from a plurality of seal bar pairs using these methods, the reference seal bar pair is designated as the first and other seal bar pairs are numbered. Is possible.

  The displacement sensor 40 measures the distance to each seal bar pair and outputs the value. The distance between the displacement sensor 40 and each seal bar pair is the assembled state of the parts constituting each seal bar pair. Usually, they are slightly different from each other. Therefore, in order to detect whether or not a foreign object has been caught, for example, instead of comparing the distance values of adjacent seal bar pairs, the measurement distance of the same round of the same seal bar pair is compared with the measurement distance of the previous round. You had better.

  Therefore, the calculation / control unit 42 calculates the difference between the current measurement distance of the same seal bar pair measured by the displacement sensor 40 and the measurement distance of the previous rotation and becomes a value larger than a preset threshold value. In such a case, processing such as determining that a foreign object has been caught is performed.

  Table 1 shows an example of measurement results. A difference between the measured value of the previous round and the measured value of the current round is obtained, and the difference is compared with a threshold value to determine whether the foreign object is caught. In the next round, the measured value of the current round becomes the measured value of the previous round, the measured value of the next round is input to the measured value of the current round, the difference is calculated, and compared with the threshold value.

By the way, since the height at which the displacement sensor 40 is installed is as high as the pass line 100 of the film 101, the film 101 in the gap portion between adjacent pairs of seal bars may be detected. .
That is, when the displacement sensor 40 is a laser displacement sensor, the laser light hits the film 101 and diffusely reflects, and the displacement sensor detects a part of the reflected light, which may cause erroneous detection.

  Therefore, as shown in FIG. 9, if the irregular reflection preventing plate 26 is attached to the movable seal bar 3 so as to close the gap between adjacent seal bar pairs, the laser light from the displacement sensor 40 may reach the film 101. Disappear. As a result, since the laser beam is not irregularly reflected on the film 101, erroneous detection due to the irregular reflection of the laser beam is eliminated, and the displacement sensor measurement surface can be stably detected.

  FIG. 9 is a top view for explaining the case of a seal bar pair using the movable seal bar 3b and the measurement plate 25. FIG. The measurement plate 25 is attached to the traveling direction (arrow A) side of the movable seal bar 3b, and the irregular reflection preventing plate 26 is attached to the opposite side. The surface of the irregular reflection preventing plate 26 facing the displacement sensor 40 is behind the measurement surface 31 of the measurement plate 25 so as not to prevent the displacement sensor 40 from detecting the measurement plate 25.

  In order to cover the laser beam from the displacement sensor 40 so as not to reach the film 101 by the irregular reflection preventing plate 26 and the measuring plate 25 attached to the pair of adjacent seal bars, the irregular reflection preventing plate 26 and the measuring plate 25 are covered. Design the size and installation position 25 so that an overlap portion is formed.

  In the case of a seal bar pair using the movable seal bar 3a that does not have the measurement plate 25, the irregular reflection prevention plate 26 is attached to one side so as to cover the vicinity of adjacent seal bar pairs. Alternatively, one having a size that can be covered so that an overlap portion can be formed between the gaps between adjacent seal bar pairs may be attached to each side.

  Further, a mesh-like groove is formed on the seal surfaces of the movable seal bar 3 and the fixed seal bar 1, and when the film 101 is sealed, this mesh is transferred to the product. If the mesh shape of the reference seal bar pair is slightly different from the shape of other seal bars, the position of the product sealed by the reference seal bar pair will be the product in a connected state (before individual cutting). It is possible to know the number of the sealed seal bar pair by counting the number from the first.

  Further, when a certain seal bar pair passes the detection position of the displacement sensor 40, the distance measurement by the displacement sensor 40 can be performed a plurality of times. Therefore, if the average value of a plurality of measurement values obtained by the plurality of measurements is used as the distance value of the seal bar pair, foreign object biting detection can be performed with higher accuracy.

DESCRIPTION OF SYMBOLS 1 ... Fixed seal bar 2 ... Movable arm 3 ... Movable seal bar 4 ... Movable seal bar 5 for reference | standard ... Film guide 6 ... Rotary table 7 ... Filling nozzle 8 ... Content metering mass table 10 Foreign matter biting detection mechanism 20 Pin 21 connecting fixed seal bar and movable arm Cartridge heater 22 Cam follower 23 Movable arm and movable seal bar Pin 24 for connecting the springs ... Measurement plate 26 ... Diffuse reflection preventing plate 30 ... Displacement sensor measurement surface 31 ... Displacement sensor measurement surface 40 ... Laser displacement sensor 41 ... Circumference sensor 42 ... Calculation / control unit 100 ... Pass line 101 ... Film

Claims (9)

A plurality of seal bar pairs having a fixed seal bar, a movable arm, and a movable seal bar are installed on a disk-shaped rotary table, and the movable seal bar and the fixed seal bar attached to the movable arm, In a rotary filling and packaging machine that conveys the base film as the rotary table rotates while sandwiching and sealing a predetermined portion of a long base film that has been half-folded in advance,
A measurement surface provided on a surface opposite to the seal surface of the movable seal bar;
A laser displacement sensor installed outside the rotary table and capable of measuring a distance between the seal bar pair and the measurement surface when the pair is completely closed;
The distance value output by the laser displacement sensor is received, the difference between the distance value between the previous rotation and the current rotation of the same seal bar pair is calculated, and it is determined from the difference whether the seal bar pair has caught a foreign object. Calculation / control section,
A foreign matter biting detection mechanism in a rotary filling and packaging machine, comprising:   The foreign object biting detection mechanism according to claim 1, wherein the measurement surface has a cylindrical surface shape having the same curvature R as a locus of the measurement surface when the rotary table rotates. A reference seal bar pair, which is one of the plurality of seal bar pairs, has a measurement surface up to a position higher than the measurement surface of the other seal bar pairs;
A circling sensor is disposed at a position where only the measurement surface of the reference seal bar pair can be detected,
The calculation / control unit detects a reference seal bar pair by receiving a signal output when the circumference sensor detects the measurement surface of the reference seal bar pair, and detects each of the other seal bar pairs. The foreign object biting detection mechanism according to claim 1, wherein a seal bar number can be assigned. A plurality of seal bar pairs having a fixed seal bar, a movable arm, and a movable seal bar are installed on a disk-shaped rotary table, and the movable seal bar and the fixed seal bar attached to the movable arm, In a rotary filling and packaging machine that conveys the base film as the rotary table rotates while sandwiching and sealing a predetermined portion of a long base film that has been half-folded in advance,
A measurement plate attached to the movable seal bar and having a measurement surface;
A laser displacement sensor installed outside the rotary table and capable of measuring a distance between the seal bar pair and the measurement surface when the pair is completely closed;
The distance value output by the laser displacement sensor is received, the difference between the distance value between the previous rotation and the current rotation of the same seal bar pair is calculated, and it is determined from the difference whether the seal bar pair has caught a foreign object. Calculation / control section,
A foreign matter biting detection mechanism in a rotary filling and packaging machine, comprising:   The measurement surface has a cylindrical surface shape having the same curvature R as the trajectory of the measurement surface when the rotary table rotates, or a planar shape having an inclination equivalent to the curvature R. The foreign matter biting detection mechanism according to claim 4. Measurement in which the measurement plate attached to a reference seal bar pair, which is one of the plurality of seal bar pairs, is higher than the measurement surface of the measurement plate attached to another pair of seal bars. Has a surface,
A circling sensor is disposed at a position where only the measurement surface of the reference seal bar pair can be detected,
The calculation / control unit detects a reference seal bar pair by receiving a signal output when the circumference sensor detects the measurement surface of the reference seal bar pair, and detects each of the other seal bar pairs. The foreign object biting detection mechanism according to claim 4, wherein a seal bar number can be assigned.   2. Only one pair of the plurality of seal bar pairs is characterized in that the seal seam formed on the seal surfaces of the fixed seal bar and the movable seal bar is different from other seal bar pairs. The foreign matter biting detection mechanism according to any one of?   An irregular reflection preventing plate is installed on the side surface of the movable seal bar so as to close a gap between the pair of adjacent seal bars to prevent the laser light from the laser displacement sensor from being irradiated on the base film. The foreign matter biting detection mechanism according to any one of claims 1 to 7,   9. The distance value between the laser displacement sensor and a seal bar pair is an average value of a plurality of measured values obtained when the seal bar pair passes. The foreign matter biting detection mechanism described.

Images