JP2004317477A - Leakage inspection method and device for sealed part of package - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To inspect the air leakage in a package sealed portion for sealing foods or the like, using small chambers, to detect the presence of pinholes with high probability. <P>SOLUTION: A packing port of the package 30 packed with a packed object and sealed in the packing port is surrounded air-tightly by the pair of adjacent small chambers 44, the sealed part of the package 30 is clampedly pressed by a pair of clamping bars 52 operated by a fluid cylinder 54, and air in the chambers 44 is started to be sucked by a vacuum line 75 at the same time. When a pressure difference to the residual air in the packing port 65 reaches a set value by a pressure drop value in the chambers 44, the vacuum line 75 is closed to keep an inside of the chambers 44 in a sealed condition, clamping action for the clamping bars 52 is released, the air in the packing port 65 is instantaneously leaked out from the pinhole to change pressure in the chambers 44 when the pinhole exists in the sealed part of the package 30, and the pressure change is detected by a sensor 67. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method and an apparatus for performing an air leak inspection of a sealed portion of a package body in which foodstuffs and the like are sealed using a pressure-resistant chamber.

  In a sealed package in which the opening edge of a wrapper filled with a package is heated and sealed, even if there is even a slight air leak, the quality of the package is changed. An inspection method is used in which the chamber is housed in the chamber and the inside of the chamber is decompressed, and a subtle air pressure leaking from the package to the chamber is detected. In other words, if a pinhole is present in the sealed portion, the pressure in the pressure-resistant chamber increases due to air leakage, and the leakage of the package can be detected by measuring a change in the pressure.

  The above inspection method will be described with reference to FIG. While performing air suction in the pressure-resistant chamber containing the sealed package, the pressure in the chamber is measured by measuring the set time t when the pressure value a of the chamber normally reaches a full vacuum value of 0. If an error in the ultimate pressure value b has occurred, it is possible to detect that there is a delay in pressure rise as indicated by the imaginary line c due to air leakage from the package.

However, the error b cannot always be measured remarkably as shown in the figure depending on the size of the pinhole, and the decompression value a of the chamber also depends on the ambient temperature or the moisture ratio in the air at a set time t. Since the full vacuum does not always reach 0. Mps, there is a problem that such measurement is somewhat incomplete.
JP-A-59-133445

  According to the present invention, in order to particularly enhance the effect of detecting a very small number of pinholes, the air suction is stopped after a pair of small chambers are hermetically covered around the bag mouth of the package and the air in the chambers is forcibly sucked. At the same time, the sensor is configured to detect a change in conditions in the chamber at the same time that the clamping bar is opened.

  The conventional concept of enclosing the entire package with a pressure-resistant chamber has been abolished, and the volume of the pressure-resistant chamber has been reduced to improve the reliability and efficiency of pinhole detection.

  FIG. 2 shows a rotary type in which eight sets of two arms 12 are provided on a peripheral edge of a rotor 11 with a pin 15 as a pivot point, and a clamp 13 is provided at an open end of each of the arms. It is a top view of the packaging machine 14. The lever 16 fixed to the pin 15 is pressed against the cam 17 by the power of the tension spring 18 installed between the pair of arms 12, so that the rotor 11 causes the clamps 13 to move 45 degrees at a time along a circular orbit. When intermittently moved, the pair of fan-shaped gears 19 meshing with each other displaces the distance between the pair of clamps 13 in accordance with the shape of the cam 17.

  FIG. 3 is a sectional side view of the bagging and packaging machine. The rotor 11 described above is supported at the upper end of a vertical axis 22 supported by a bearing 21 on a machine base 20. The tension arm (not shown) inside the clamp arm 12 installed on the peripheral surface of the rotor 11 pulls the rod 23 in the direction of the arrow 24 as shown in FIG. However, when the swinging pusher 26 about the pin 25 in FIG. 3 applies a pressing force to the roll pin 27 protruding from the arm 12, the tension spring inside the arm is compressed and the clamp 13 is opened.

  As described above, each clamp 13 in FIG. 2 opens and closes at a specific location. Therefore, the vacuum cup 28 that sucks the wrapper 10 in the laminated box sequentially receives the wrapper 10 on each of the circulating clamps 13. You can pass it. Then, the wrapping bag 10 which is hung by the clamp opens or tightens the opening of the wrapping bag according to the change in the interval between the pair of clamps 13, so that in one section, the wrapping bag is filled with the wrapping bag through the morning glory hopper 29. In the second section, a pair of seal bars 31 can release the welded seal at the upper opening edge or bag mouth, and in the third section, the sealed package 30 can be released from the clamp as described above. is there.

  FIG. 5 shows a leak inspection machine installed in the three sections, which rotatably supports a vertical spindle 34 on a bearing 33 on a base 32, and The two radial rails 35 project in the horizontal radial direction from both sides of the gear box 38A fixed to the upper end of the gear box 38A, and the support block 36 is slidably disposed on each of the radial rails 35.

  As shown in FIG. 6, the two radial rails 35 are composed of a screw rod 38 disposed inside a pipe 37 and a slide magnet 39 that engages with the screw rod 38, and are provided with an operation motor 40 provided on the gear box 38A. The shaft and the screw bar 38 are engaged with each other via a bevel gear 41. By rotating the screw bar 38 forward and reverse by the power of the operation motor 40, the slide magnet 39 is displaced. The support block 36 is also displaced along the outside of the pipe 37 by being attracted by the magnetism 39.

  FIG. 1 shows a pair of small chambers 44 supported on the support block 36 shown in an enlarged manner via pivot pins 43 so as to be openable and closable, and a cross section (arrow VII) in the middle of the figure can be seen. As is apparent from FIG. 7, both ends of the chamber 44 are respectively supported by pivot pins 43 on the front and rear surfaces of the support block 36 supported by two radial rails 35 via suspension arms 46, and a pair of fluids on both sides are provided. The piston rod 48 of the cylinder 74 is engaged with the suspension arms 46 to control the opening and closing of the chambers 44 and 45. That is, by applying the power of the fluid cylinder 47 up and down to the pin 43A in FIG. 1, the two chambers 44 and 45 are opened as shown by the phantom line 44a.

  The support block 36, also shown in FIG. 1, has a cylindrical sleeve 49 hanging down below its center, and further forked bifurcated brackets 50, 50 from the sleeve 49 (see also FIG. 7). An opening / closing link 53 having a holding bar 52 connected to a lower end thereof is pivotally supported, and a pin 56 at a lower end of a piston rod 55 of an upper main fluid cylinder 54 of a support block 36 is engaged with a long hole 57 of the opening / closing link. Combine. In short, the operation of the main fluid cylinder 54 causes the pair of holding bars 52 to open and close about the pins 51 respectively. The two seal rings 98 wound around the cylindrical sleeve 49 are used for hermetic sealing with a hole at the boundary between the inner surfaces of both chambers 44.

  Therefore, when the package 30 supported by the clamp arm 12 reaches and stops between the pair of clamp bars 52 that are opened as shown in FIG. 5, the clamp bars 52 close the bag opening of the package, that is, the sealed portion. It moves along the radial rail 35 at the same time as the opening of the clamp 13 and the opening of the clamp 13, and the package 30 is carried out of the bag-filling machine. That is, the package 30 is carried out in the direction of the arrow 58 in FIG. In this case, since there is a possibility that both clamps 13 may interfere with the unloading action of the package 30, the following mechanism retracts both clamps 13 to both sides as indicated by an arrow 59.

  That is, a ring 63 supported rotatably around the bearing 21 of FIG. 3 and an operation shaft 61 supported on the machine base 20 are connected via a crank 62 while a cam 63 coupled to the ring 60. Is disposed at the end of the lever 16 already described, in the area where the pulley 64 passes. In FIG. 2, the cam 63 rotates independently in response to the unloading operation of the package 30 in the section 3 to temporarily open both clamp arms 12 to both sides.

  In FIG. 3, when a pair of holding bars 52 catches the package 30 and separates it from the clamp 13 along the radial rail 35, a pair of chambers 44 from outside the both holding bars 52 hermetically close the bag opening of the package 30. Pinch.

  In short, when both chambers 44 cover the bag mouth 65 of the package 30 from both sides as shown in FIG. 1, air suction in the airtight chamber 44 through the vacuum joint 66 is started. In this case, the pinching pressure of the bag mouth by both holding bars 52 is an act of preventing air leakage from the pinhole in the already-sealed portion beforehand. When the holding bar 52 is separated from the sealed portion of the package 30 by operating the cylinder 54 at a timing when a predetermined pressure difference is generated between the sealed portion and the vacuum value in the chamber 44, a pinhole is temporarily formed in the sealed portion. Is present, the residual air inside the bag mouth 65 blows out from the pinhole into the chamber 44, and the vacuum gauge 67 installed in the chamber catches a sudden change in the pressure in the chamber 44. That is, as shown in FIG. 10, the sudden change B of the chamber pressure A that falls in a parabolic shape is captured, and an alarm signal is transmitted from the controller. In the same figure, the measurement of the pressure change of the chamber is illustrated as being performed in an environment of a value of 0.Mps, but even in such a high vacuum environment, by performing in an environment where the condition change can be captured, Efficiency can be improved.

  In the above operation, as shown in step S1 of FIG. 9, first, the clamping bar separates the package from the endless track of the bag-filling and packaging machine. Next, as in step S2, the small chamber is closed from outside so as to cover the bag mouth of the package. Next, in step S3, air suction in the chamber is performed. As shown in step S4, after the set time, the air suction is stopped, and the movement of the air in the chamber is stopped. In this case, the pressure value in the chamber is detected by a sensor and stored. At the same time, step S5 releases the holding bar. Step S6 measures the pressure of the chamber. The controller issues an alarm if there is a change in the detected pressure value in the chamber between the already stored pressure value. In step S7, the chamber is opened by introducing air. The above steps are repeated.

  The sensor 67 may be a sensor for fluorescence analysis, that is, a sensor for measuring the residual gas concentration by reacting air molecules or gas molecules by fluorescence, in addition to the sensor for measuring the pressure change as described above. Also, the present invention can be applied to detection of gas generated from a package.

  The main shaft 34 in FIG. 5 is connected to a motor 71 via a lower bevel gear 70. The motor 71 intermittently rotates the main shaft 34 by 180 degrees so that two sets of small chambers 44 approach the package 30 so as to coincide with the intermittent transfer of the package 30. When the support block 36 in FIG. 6 is displaced in the direction of arrow 72 to separate the package from the packaging machine, the right-hand chamber 44b in FIG. 5 is displaced toward the end of the radial rail 35, and the packaging machine is rotated by rotating the main shaft 34 as it is. On the subsequent package 30.

  The rotary valve 73 installed on the bearing 33 in the previous figure alternately switches the connection between the vacuum pump 74 and the two sets of small chambers 44a and 44b via the tube 75. That is, the lower panel of the rotary valve 73 is fixed to the bearing 33, and the upper panel rotates integrally with the main shaft 34. For this reason, on the surface of the lower plate 73A shown in FIG. 8, the imaginary line port 76 formed in the upper plate circulates clockwise, and the port 76 is connected to the arc 76 only while the port 76 is connected to the arc groove 77 formed in the plate 73A. A vacuum is applied, and then the movement of the air is stopped while the air passes through the area 99, and the air is applied to the port 76 by connecting to the air hole 78. In short, since the port 76 is connected to the chamber 44 via the tube 75 in FIG. 1, a vacuum pressure or an atmospheric pressure acts on the chamber 44 at a predetermined timing.

  The three endless grooves 79 formed on the board 73A of FIG. 8 are connected to a vacuum pump through the collecting groove 80. Therefore, the three auxiliary ports 81 moving along the endless grooves 79 always have a vacuum. Pressure acts. These three auxiliary ports 81 are connected to the three fluid cylinders 47 and 57 of FIG. 7 through electromagnetic valves 82 and 83 installed on the upper part of the rotary valve in FIG. Is controlled by the operation of each of the solenoid valves 82 and 83.

  As shown in FIG. 11, a package 10 having a screw cap 85 at the bag mouth is commercially available. When the package is an empty package, the bag bottom 86 is opened and the packaged object is removed from this portion. In such a package, since the bag bottom 86 substantially contacts the bag mouth, the sealed portion 87 of the bag mouth is sandwiched by the sandwiching bar 52, and the leakage inspection is performed by the method already described. Will be done.

  The sensor 67 may be a sensor for trend analysis, that is, a sensor for reacting air molecules or gas molecules by fluorescence to measure the residual amount of gas, other than the sensor for measuring the pressure change as described above.

  The "means for issuing an alarm" described in the claims is a device for notifying such a change in conditions when gas leakage is detected from a pinhole in a small chamber, and a device for automatically removing a defective pinhole package. Is also included.

  In the pressure reduction A of the small chamber which is repeatedly performed in FIG. 10, since the drop value A does not greatly change if the set time t is always constant, the pressure value in the chamber is stored immediately after the elapse of the set time t to change the condition B May be detected, but it is considered that the condition change B after the set time t can be detected relatively accurately without performing the storage operation of the pressure value.

  The package to be inspected may have applications other than flexible packaging. It is also applicable to detection of gas generated from a package.

Front sectional view of a small chamber Top view of bag packing machine Side view of the previous figure Perspective view of a package supported by a clamp arm Side view of leakage inspection device Partial sectional view of the previous figure Illustration of small chamber Illustration of rotary valve Action explanation diagram Illustration of inspection action Illustration of conventional configuration Explanatory drawing of 2nd Example

Explanation of reference numerals

DESCRIPTION OF SYMBOLS 10 ... Envelope 11 ... Rotor 12 ... Clamp arm 13 ... Clamp 14 ... Bag packing machine 34 ... Spindle 35 ... Radiation rail 36 ... Support block 37 ... Screw rod-movement mechanism 39 ... Slide magnet-movement mechanism 44 ... Small chamber 52 ... clamping bar 54 ... fluid cylinder-clamping bar opening mechanism 67 ... sensor 71 ... motor-mechanism for intermittently rotating the main shaft 73 ... rotary valve-air suction and stop mechanism 74 ... vacuum pump-air suction mechanism

Claims (5)

The wrappers respectively supported by a plurality of sets of a pair of clamps arranged at equal intervals on the endless track are intermittently moved along the endless track, and are covered by the sections in one section of the endless track. In a bag-filling and packaging machine that sequentially performs filling of a package, a welding seal at an upper opening edge of the wrapping bag in a second section, and release of a package from the clamp in a third section, from a clamp in the third section. After the sealed portion of the bag opening of the package is squeezed by a pair of sandwiching bars in accordance with the release timing of the package and the package is carried out of the endless track, the package is sealed from the outside of the sandwiching bar. After airtightly covering a pair of small chambers around the bag mouth and forcibly sucking air in the chamber, the air suction is stopped, and at the same time as the holding bar is opened, a sensor is used. Leak inspection method for detecting a condition change in the Chiyanba I. The wrappers respectively supported by a plurality of sets of a pair of clamps arranged at equal intervals on the endless track are intermittently moved along the endless track, and are covered by the sections in one section of the endless track. The filling of the package is arranged in the second section with the welding seal at the upper opening edge of the wrapper in the third section of the bagging and packaging machine which sequentially releases the package from the clamp in the third section. A device for clamping the sealed portion of the bag opening of the package with a pair of clamping bars and discharging the package out of the endless track in accordance with the package release timing of the clamp; A mechanism for airtightly covering a pair of small chambers around the bag mouth of the package from the outside of the holding bar and forcibly sucking the air in the chamber, and stopping the air suction after the air suction. A mechanism for releasing the bag mouth by the holding bar in response to the stop of the air suction, a sensor for detecting a condition change in the pressure-resistant chamber simultaneously with the release of the holding bar, and a sensor for responding to the condition change. Leakage inspection device consisting of a mechanism that issues an alarm. The wrappers respectively supported by a plurality of sets of a pair of clamps arranged at equal intervals on the endless track are intermittently moved along the endless track, and are covered by the sections in one section of the endless track. The filling of the package is arranged in the second section with the welding seal at the upper opening edge of the wrapper in the third section of the bagging and packaging machine which sequentially releases the package from the clamp in the third section. An apparatus, wherein the apparatus includes at least two or more radial rails arranged horizontally radially around a vertically arranged main axis, and each of the support blocks slidably disposed along each of the radial rails has a hanging shape. The support block is radiated so that the package is carried out of the endless track of the packaging machine by the pair of clamping bars and the clamping bar in accordance with the package release timing of the clamp. A pair of small chambers, each of which is openably and closably supported by the support block, to form an airtight chamber around the bag opening of the package taken out of the endless track, while having a movement mechanism for displacing along the strip; A mechanism for forcibly sucking the air in the chamber in accordance with the closing of the small chamber, a mechanism for stopping the air suction after the air suction, and a bag opening by the holding bar corresponding to the stop of the air suction. A mechanism for releasing, a sensor for detecting a change in conditions in the pressure-resistant chamber at the same time as the release of the clamping bar, and an intermittent rotation of the main shaft for associating each of the support blocks with intermittent movement of a clamp of the packaging machine. A leak inspection device configured by a mechanism for causing a leak. 4. The apparatus according to claim 2, wherein a sensor for detecting a condition change in the chamber is formed by a vacuum gauge, and an alarm is issued in response to a change in the vacuum value in the chamber. 4. The apparatus according to claim 2, wherein a sensor for detecting a change in conditions in the chamber is formed by a gauge for measuring air molecules, and an alarm is generated in response to a change in air molecules in the chamber.