JP2001240024A - Biting-detecting device for article to be packaged in bag- making filling machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To clearly judge the generation of a biting of an article to be packaged by judging whether there is a biting of the article to be packaged or not based on a sound pressure level in a specified frequency zone of a sound which is generated at the time of the end seal. SOLUTION: This biting-detecting device for the article to be packaged in a bag- making filling machine is a detecting device to detect that the article 20 to be packaged is bited by sealing body 32 of an end seal mechanism 30 in the bag-making filling machine. The biting-detecting device is equipped with a sound-detecting means (the microphone 42 of a noise meter 40) and a judging means (e.g. a control device 44). In this case, the sound detecting means is provided in the vicinity of an engaging location of the sealing body 32. The judging means judges the generation of the biting when the sound pressure level in the specified frequency zone for a sound detected by the sound detecting means exceeds a set value which is set in advance. Then, the frequency zone is set at a region wherein a minimum value of the sound pressure level at the time of the generation of the biting exceeds a maximum value of the sound pressure level at the time of a normal operation of the bag-making filling machine.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bite detecting device for detecting that an object to be packaged has been bitten by a seal member of an end seal mechanism at the time of end sealing in a bag making and filling machine.

[0002]

2. Description of the Related Art In a horizontal bag making and filling machine, an object to be packaged is supplied into a cylindrical packaging material at a predetermined interval with respect to a sealing timing of an end sealing mechanism. However, the supply position of the packaged product may deviate from the normal position with respect to the seal timing due to factors such as machine vibration, the form of the packaged product, or an error in the timing of feeding the packaged product from the supply conveyor. This is because the article to be packaged does not fit in a proper position in the packaging material, and the article to be packaged may be caught in the seal body of the end seal mechanism at the time of end sealing the packaging material. Since the package in which this biting has occurred is a defective product with an incomplete seal, it is necessary to separate and remove the package from the normal package.

[0003] Various means have been proposed for detecting the bite of the packaged object.
The technique disclosed in Japanese Patent Application Laid-Open No. 6-171621 is one of them. In this technique, a sensor detects a vibration level generated at the time of sealing (thermal bonding) of the packaging material, and when the detected vibration level is higher than a preset level, the object to be packaged at the sealed portion is not caught. It is determined that there was.

[0004]

However, in the packaging machine, inherent vibrations during normal operation and vibrations driven by the motor of the conveyor always occur, and the level may exceed the set level depending on the vibration. . In this case, it is not possible to accurately determine the occurrence of the bite, and in particular, it is often difficult to distinguish from other vibrations around the machine at a vibration level such that a packaged object such as a rice cracker or a biscuit bites. . An object of the present invention is to solve the above-described problem, and an object of the present invention is to determine whether or not an article to be packaged has been jammed based on a sound pressure level of a sound generated at the time of end sealing in a predetermined frequency band. Thus, it is clearly determined that the bite of the packaged object has occurred.

[0005]

Means for Solving the Problems The present invention has been made to achieve the above-mentioned object, and the invention according to claim 1 is characterized in that an article to be packaged is caught in a seal body of an end seal mechanism in a bag making and filling machine. A device for detecting the bite of an object to be packaged in a bag making and filling machine for detecting a sound, wherein a sound detecting means provided in the vicinity of the meshing position of the seal body, and a predetermined sound in the sound detected by the sound detecting means. And a determining means for determining that the biting has occurred when the sound pressure level in the frequency band of (1) exceeds a preset value. The frequency band is set to a region where the minimum value of the sound pressure level at the time of the occurrence of the bite exceeds the maximum value of the sound pressure level at the time of normal operation of the bag making and filling machine.

According to this configuration, it is determined whether or not the packaged object has caught in the seal body based on the sound pressure level in the frequency band in the sound generated at the time of the end seal. Further, since this frequency band is a frequency range in which the minimum value of the sound pressure level when the packaged object is caught exceeds the maximum value of the sound pressure level in the normal operation of the bag making and filling machine, There is little influence on the detection due to the inherent operation noise and the surrounding environmental noise during the normal operation of the bag making and filling machine. For this reason, even if the object to be packaged, such as a rice cracker or a biscuit, is a small sound such as when it is bitten by the seal, the occurrence thereof can be clearly detected. The frequency band is preferably from 12 KHz to 20 KHz. In this frequency band, the influence of environmental noise and the like on the detection of bite is further suppressed.

According to a third aspect of the present invention, there is provided an apparatus for detecting the bite of an article to be packaged in the bag making and filling machine according to the first aspect,
The sound detection timing by the sound detection means is set in accordance with the seal timing by the seal body of the end seal mechanism. Thus, the influence of environmental noise around the bag making and filling machine on the detection of the sound when the packaged object bites can be minimized, and the occurrence of biting can be determined more accurately.

According to a fourth aspect of the present invention, there is provided a device for detecting the bite of an article to be packaged in the bag making and filling machine according to the first aspect,
The determination means has a function of correcting the set value based on a change in the maximum sound pressure level during normal operation of the bag making and filling machine. With this correction function, the occurrence of biting can be accurately determined according to the environmental change at each time.

According to a fifth aspect of the present invention, there is provided an apparatus for detecting the bite of a packaged object in the bag making and filling machine according to the first aspect,
The determination means determines that biting has occurred when the sound pressure level exceeds the set value continuously for a predetermined time.
The determining means may determine that the bite has occurred when the sound pressure level exceeds the set value a plurality of times within a predetermined time, and the sound pressure level within the predetermined time is equal to the set value. It may be determined that the bite has occurred when the average value of the values exceeds the set value. In this case, the occurrence of biting can be accurately determined without being affected by an instantaneous change in environmental noise or the like.

[0010]

Embodiments of the present invention will be described below. FIG. 1 is a schematic diagram showing a related configuration between a horizontal bag making and filling machine and a bite detecting device, and FIG. 2 is a plan view showing a part of FIG. First, as apparent from FIG. 1, a film 10 used as a packaging material for bag making is wound in a roll shape,
From here, it is continuously fed by the rotational drive of a pair of feeding rollers 12, and is sent to a bag making mechanism 16 via a plurality of guide rollers 14. In the bag making mechanism 16, the film 10 is formed into a cylindrical shape, and the packaged object 20 supplied from the supply conveyor 22 is formed into the cylindrical film 10.
Are sent at regular intervals. Note that the packaged object 20 targeted in the present embodiment is a rice cracker, a biscuit, or a similar confectionery.

The film 10 coming out of the bag making mechanism 16
Is sent to the end seal mechanism 30 together with the packaged object 20 by the rotation of the feed roller 24 and the center seal roller 26 arranged on the lower surface side of the guide plate 28 for guiding the packaged object 20. At the same time, the film 10 is continuously sealed by the seal roller 26 at the vertical mating portion located below the guide plate 28.

In the end seal mechanism 30, a pair of seals 32 arranged above and below the tubular film 10 are provided.
Is rotating synchronously. The film 10 is end-sealed at a predetermined timing by the engagement of these seals 32, and at the same time, the cutter 34 provided in both seals 32 is provided.
Cuts the middle of the end seal portion. As a result, the film 10 that has been continuous up to that time is separated into individual bags (packaged goods) each of which wraps the packaged object 20, and is sequentially carried out by the delivery conveyor 36.

If the position of the packaged object 20 fed from the supply conveyor 22 into the cylindrical film 10 as described above does not fall within the regular position for the reason described above, the end seal is required. The packaged object 20 may bite into the seal body 32 of the end seal mechanism 30. Therefore, a device for detecting this biting will be described. First, near the meshing position of the seal body 32 in the end seal mechanism 30, a sound detection unit of the microphone 42 of the sound level meter 40 is disposed so as to be directed to the meshing position. The sound level meter 40 can analyze the frequency of the sound detected by the microphone 42, and can measure the sound pressure in a set predetermined frequency band. The function of the sound level meter 40 is to output the average value of the sound pressure levels detected within a fixed time (for example, 10 msec) as the maximum value.

A signal is input to the control device 44 when the sound level meter 40 detects a sound pressure level exceeding a preset value. However, when the sound level meter 40 has only the function of measuring the sound pressure level, the control device 44 receiving the detection signal determines whether the sound pressure level exceeds the set value. In other words, this determination (judgment determination described later) may be performed by the sound level meter 40 or by the control device 44. In any case, the control device 44 outputs an operation signal to the reject means 46 on the basis of the detection signal of the sound pressure level exceeding the set value, assuming that the bite has occurred. The reject unit 46 includes a jet nozzle that blows out compressed air toward the package transfer path of the delivery conveyor 36,
The defective product is sent out by the air jetting conveyor 36.
Can be excluded from

The operation signal output from the control device 44 to the rejecting means 46 is based on the timing at which air is blown in accordance with the timing at which the jammed packaged product (defective product) is transported to the reject position by the delivery conveyor 36. It is transmitted by the expiration of the timer so that it is injected.
Further, the control device 44 may be a drive control device that is provided integrally with the horizontal bag making and filling machine and controls the driving of the machine, or may be a control device including a control circuit different from the horizontal bag making and filling machine. There may be.

The sound is detected by the microphone 42 by measuring the sound pressure in a specific frequency band set in the range of 12 KHz to 20 KHz by the function of the sound level meter 40 in decibels. This frequency band is less susceptible to the inherent operation noise and the surrounding environmental noise during the normal operation of the horizontal bag making and filling machine, and can be said to be a high frequency region in the average human audible range.

A specific frequency in the frequency band,
For example, when measuring the sound pressure level at 20 KHz, the sound pressure level of the entire band detectable by the microphone 42 is generally compared with the predetermined frequency band around 20 KHz in the measurement process by the sound level meter 40. Measure. And 20
For the measurement area before and after KHz, processing to reduce the measurement sensitivity is performed by a digital filter.
A measurement of the sound pressure level at a frequency of KHz is obtained.
The width of the frequency band that can be filtered by the digital filter can be changed in consideration of the relationship with environmental noise and the like. In addition, the same processing as described above may be performed on the measurement result extracted for each frequency by the real-time frequency analyzer used for the test described later.

On the other hand, the set value (threshold value) of the sound pressure level is not set by an empirical value or a mere data value, but is determined by a specific operation sound and a surrounding environment during a normal operation of the horizontal bag making and filling machine. This is a value obtained by adding a predetermined "permissible value" to a "reference value" obtained by measurement of noise or the like. The setting method includes, for example, the following two methods. One of them is the sound level meter 40 (in the case of outputting a signal by detecting a sound pressure exceeding a set level) by adding an "allowable value" to the "reference value" obtained by the measurement or the control device 4
4 directly inputs data to the operator. The other is provided with an automatic setting mode of a set value, and a sound level meter 40 (in the case of a type that outputs a signal by detecting a sound pressure exceeding a set level) or a control device to a “reference value” obtained by the measurement. The "allowable value" set in advance in the storage unit 44 is added, and the set value is automatically set. In the case where the automatic setting mode is provided, the “allowable value” may be a data value that can be changed as required by data input or a fixed value set by a program.

The "reference value" is obtained by measuring the operating sound and environmental noise each time the seal member 32 makes one rotation during normal operation a plurality of times in advance, and determining the sound pressure level (maximum) for each rotation of the seal member 32. Values), and the highest sound pressure level is taken. Note that the “reference value” may be temporary storage data at the time of measurement for obtaining a set value.
Further, the "allowable value" is used to increase the detection accuracy of the bite and enable a stable determination, and the sound pressure level is 1 to 3
dB.

Here, in order to obtain the frequency band,
The test was performed as follows. In this test, the horizontal bag making and filling machine was operated continuously with the capacity set at 200 bags / min, and a sound level meter and a real-time frequency analyzer were used for sound detection. The packaged object 20 is a double-layered rice cracker, and a. When the whole of the two sheets is bitten, b. When only one of the two sheets is partially bitten, c. Similarly, three types of conditions were set when the tip portion of only one of the two sheets was slightly bitten.

In comparison with the conditions a to c and the normal operation in which no biting occurs, the sound generated near the position where the sealing body 32 of the end seal mechanism 30 meshes is measured for two seconds. . The sound pressure levels in the frequency range of 25 Hz to 20 KHz obtained by this measurement were compared at predetermined frequency intervals, and as a result, the a, b, and
The frequency band in which the difference between the minimum value of the sound pressure level when biting occurs under each condition c and the maximum value of the sound pressure levels during normal operation exceeds 1 dB is from 12.5 KHz to 20 KHz.
Up to.

In this frequency band, when the frequency values that can be set by the measuring equipment used in this test were selected stepwise, they were 12.5 KHz, 16 KHz, and 20 KHz. The measurement results of the sound pressure level at these frequencies are shown in FIGS. 3 shows the case where the frequency value is 12.5 KHz, FIG. 4 shows the case where the frequency value is 16 KHz, and FIG. 5 shows the case where the frequency value is 20 KHz. Note that the horizontal axis in these drawings is the rotation angle of the seal body 32, and the triangular display indicates the position where the seal bodies 32 mesh with each other as shown in FIG. Further, from the measurement data shown in these drawings, the maximum value of the sound pressure level during normal operation, the minimum value of the sound pressure level when biting occurs under each of the conditions a, b, and c, and the difference therebetween are picked up. Then, it is as shown in Tables 1, 2, and 3. From this test result, it is assumed that a good detection result can be obtained if the frequency is approximately 12 KHz or more. By the way, almost the same result was obtained in the test in which one piece of biscuit was used as the packaged object 20. Note that the measurement of sound with a frequency exceeding 20 KHz was excluded from this test because the measuring equipment is currently extremely expensive and impractical in terms of cost.

[0023]

[Table 1]

[Table 2]

[Table 3]

According to the bite detection device having the above-described structure, the sound near the position where the seal body 32 is engaged is constantly detected by the microphone 42 (sound detection means) of the sound level meter 40 during the operation of the horizontal bag making and filling machine. Detect the frequency band (12KHz
When the sound pressure level at a specific frequency from to 20 KHz) exceeds the set value, it is determined that the packaged object 20 has bitten into the seal body 32. When biting occurs, defective products are removed from the conveyor 36 by air injection from the rejecting means 46 as described above, thereby preventing the defective products from being mixed into normal packaged products. Moreover, the frequency band is set to a frequency range in which the minimum value of the sound pressure level when the packaged object 20 bites into the seal body 32 exceeds the maximum value of the sound pressure level in normal operation. Thereby, without being affected by the inherent operation noise and the environmental noise during the normal operation of the horizontal bag making and filling machine, for example, the sound generated when the packaged object 20 such as a rice cracker or a biscuit is bitten can be generated. Occurrence can be clearly determined.

For the set value, for example, the maximum value of the sound pressure level in the normal operation within a predetermined time (for example, several minutes) from the start of the operation of the horizontal bag making and filling machine every day is measured. May be given to the “reference value”. As a result, the set value can be automatically corrected based on the correction data, and the trouble of setting each time can be eliminated, and the occurrence of biting can be accurately determined according to the environmental change at each time. Instead of always detecting the sound near the meshing position of the seal 32 by the microphone 42, the timing of the sound detection may be set in accordance with the timing of the end seal by the seal 32. Thus, the influence of environmental noise around the horizontal bag making and filling machine on detection of the biting sound can be reduced, and the occurrence of biting can be determined more accurately.

Further, it is possible to set conditions for determining that the bite has occurred by the determining means as the following A to C. A. When the sound pressure level in the frequency band exceeds the set value continuously for a predetermined time. B. When the sound pressure level in the frequency band exceeds the set value a plurality of times within a predetermined time. C. When the sound pressure level in the frequency band exceeds the set value a plurality of times continuously within a predetermined time, and when the average value of the values exceeds the set value. By setting such conditions, the occurrence of biting can be determined with high accuracy without being affected by an instantaneous change in environmental noise or the like.

As for the rejecting means 46, a mechanism such as a pusher which operates mechanically depending on the packaging speed of a horizontal bag making and filling machine may be employed instead of the air jet method. Also, this reject means 4
6 is controlled so as to be transmitted from the control device 44 when the timer expires as described above, but instead of this timer, the system provided with the drive control device of the horizontal bag making and filling machine is provided. The control may be performed by a pulse signal from a clock pulse generation unit or another control pulse generation unit. For example, when the operation timing of the rejecting means 46 is controlled by the control pulse signal of the horizontal bag making and filling machine, the synchronization accuracy between the horizontal bag making and filling machine and the rejecting means 46 is high, and the timer is set every time the packaging speed is changed. No changes are required. Further, in the present embodiment, an example in which the above-described bite detection device is applied to a horizontal bag making and filling machine has been described, but it is naturally applicable to other vertical bag making and filling machines.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a related configuration of a horizontal bag making and filling machine and a bite detection device.

FIG. 2 is a plan view showing a part of FIG. 1;

FIG. 3 is a measurement data diagram of a sound pressure level at a frequency of 12.5 KHz.

FIG. 4 is a measurement data diagram of a sound pressure level at a frequency of 16 KHz.

FIG. 5 is a measurement data diagram of a sound pressure level at a frequency of 20 KHz.

[Explanation of symbols]

 Reference Signs List 20 Packaged object 30 End seal mechanism 32 Seal body 40 Sound level meter 42 Microphone

Claims (7)

[Claims] 1. An apparatus for detecting the bite of an object to be packaged in a bag making and filling machine for detecting that the object to be packaged has caught in a seal body of an end seal mechanism in the bag making and filling machine, Sound detection means provided in the vicinity of the meshing position, and when the sound pressure level in a predetermined frequency band of the sound detected by the sound detection means exceeds a preset value, Determining means for determining that the sound pressure level has occurred, wherein the minimum value of the sound pressure level at the time of the occurrence of the bite exceeds the maximum value of the sound pressure level during the normal operation of the bag making and filling machine. Detection device for a packaged object in a bag making and filling machine. 2. An apparatus for detecting the bite of an object to be packaged in the bag making and filling machine according to claim 1, wherein the apparatus for detecting bite of an object to be packaged in the bag making and filling machine having the frequency band from 12 KHz to 20 KHz. . 3. The device for detecting the bite of an object to be packaged in a bag making and filling machine according to claim 1, wherein the sound detection timing by said sound detection means is adjusted to the sealing timing by a seal body of said end seal mechanism. A device for detecting the bite of the packaged object in the set bag making and filling machine. 4. The apparatus for detecting the bite of an object to be packaged in a bag making and filling machine according to claim 1, wherein said judging means detects a change in the maximum value of the sound pressure level during a normal operation of the bag making and filling machine. An apparatus for detecting the bite of a packaged object in a bag making and filling machine having a function of correcting the set value based on the set value. 5. The apparatus according to claim 1, wherein the sound pressure level continuously exceeds the set value for a predetermined time. A device for detecting a bite of a packaged object in a bag making and filling machine that determines that bite has occurred. 6. The apparatus according to claim 1, wherein the sound pressure level exceeds the set value a plurality of times within a predetermined time. A device for detecting the bite of a packaged object in a bag making and filling machine which determines that bite has occurred in the package. 7. The device for detecting the bite of an object to be packaged in the bag making and filling machine according to claim 1, wherein the determination unit determines that the sound pressure level within the predetermined time exceeds the set value. A device for detecting a bite of a packaged object in a bag making and filling machine that determines that bite has occurred when an average value of the values exceeds the set value.