JP2004203457A - Gas filling machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a gas filling machine which enables sealing operations to be surely performed by preventing the partial elongation of a packaging bag in the sealing of the gas-filled packaging bag. <P>SOLUTION: This gas filling machine is equipped with a sealing mechanism part 6 for sealing an opening of the packaging bag 21, which is provided in a packaging area, by bringing the opening into a pressure contact state by means of upper and lower sealing blocks 31a and 31b, a vacuum pump for deaerating the inside of the packaging bag 21, and a gas nozzle 5 for infilling an inert gas into the deaerated packaging bag 21. Protrusions 36 for holding an unheated part on the side of a storage part with respect to a sealing part of the packaging bag 21 are provided on the mutually opposed pressure contact surfaces of the sealing blocks 31a and 31b. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a gas filling machine that fills an inside with an inert gas or the like in a state where an article to be packaged is stored in a packaging bag and seals an opening of the packaging bag.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, a vacuum packaging machine that fills an inert gas or the like with a packaged object such as food stored in a packaging bag made of a resin film or the like and seals an opening of the packaging bag is disclosed in, for example, No. 19723 (Patent Document 1).
[0003]
In the invention described in Patent Document 1, an inert gas is filled from an opening of a packaging bag set in a chamber, and the opening is sealed by pressing the opening with an upper sealing member and a lower sealing member. And a vacuum pump for reducing the pressure in the chamber.
[0004]
A vacuum packaging machine reduces the pressure around the packaging bag containing foods and the like, and then fills the packaging bag with an inert gas or the like and seals it. There is also a gas filling machine that fills an inert gas without reducing the pressure and then seals the opening of the bag. For example, as shown in FIG. 6, a gas nozzle 52 is inserted into an opening of a packaging bag 51 containing a packaged object 50 such as food, and the vicinity of the opening of the bag is pressed with rubber 53. After degassing, an inert gas is filled into the packaging bag 51 from the gas nozzle 52, and in this state, the opening of the packaging bag 51 is pressed against the upper and lower sealing blocks 55 and 56 provided with the heater wires 54 and thermally welded. By doing so, it is sealed.
[0005]
[Patent Document 1]
JP, 2002-19723, A
[Problems to be solved by the invention]
By the way, in the conventional gas filling machine, when gas is charged into the packaging bag 51 from the gas nozzle 52, the vicinity of the opening of the bag into which the gas nozzle 52 is inserted is pressed by the upper and lower rubbers 53. Deviation can be prevented. However, when the gas-filled packaging bag 51 is pressed against the upper and lower sealing blocks 55 and 56 to perform thermal welding, the inflation force of the gas filled in the packaging bag 51 becomes as shown by the arrow in FIG. It acts as a pulling force to pull the film constituting the packaging bag, thereby pulling the portion softened by the heat of the heater wire 54 between the upper and lower sealing blocks 55 and 56, and the sheet of the bag becomes thinner. In some cases, the heat welding cannot be performed successfully (for example, the heat-welded portion is broken or the welding is poor). Such a problem may occur not only in the gas filling machine but also in the vacuum packaging machine.
[0007]
The present invention has been made in view of such circumstances, and an object of the present invention is to provide a gas that can prevent partial elongation of a packaging bag at the time of sealing a gas-filled packaging bag, thereby preventing poor sealing. It is to provide a filling machine.
[0008]
[Means for Solving the Problems]
SUMMARY OF THE INVENTION The present invention has been proposed to achieve the above object, and according to the present invention, the opening of a packaging bag set in a packaging area is press-welded with upper and lower sealing blocks and thermally welded. A sealing mechanism for performing the above operation, and a gas nozzle for filling the inside of the packaging bag with gas. The packaging bag is filled with gas while the packaged object is stored in the packaging bag, and the opening of the packaging bag is thermally welded. In a gas filling machine that seals with
On the press-contact surface of the sealing block, a pressing holding portion for pressing and holding the non-heating portion located on the storage portion side of the sealing portion of the packaging bag is provided, and the non-heating portion of the packaging bag body is pressed by the pressing holding portion. This is a gas filling machine characterized by performing thermal welding while sandwiching.
[0009]
According to a second aspect of the present invention, the pressing and holding portion is constituted by a protrusion formed on one of the opposing press contact surfaces of the upper and lower sealing blocks on the storage portion side of the packaging bag with respect to the heater wire. The gas filling machine according to claim 1, wherein
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view showing the overall appearance of the gas filling machine of the present invention. FIG. 2 is a front view of the gas filling machine, and FIG. 3 is a side view thereof. FIG. 4 is a schematic diagram of a main part showing the internal structure of the gas filling machine of the present invention. FIG. 5 is an enlarged view of a main part showing an example of a sealing mechanism in the gas filling machine of the present invention.
[0011]
As shown in these drawings, the gas filling machine 1 of the present embodiment is provided with a mounting tray 29 on the upper part of the housing 2 in a state where the mounting tray 29 is inclined downward toward the rear of the housing 2. Is provided with a cover-shaped heater arm 3 which can be opened and closed about a support shaft 9 disposed on both sides closer to the rear half of the housing, and a gas nozzle 5 is provided near the front surface of the casing in a packaging area 4 which is divided by the heater arm 3. A sealing mechanism 6 for sealing the opening of the packaging bag 21 is provided near the tip of the gas nozzle 5 and provided in the rear of the housing 2. A vacuum pump 19 and a control device (FIG. (Not shown), and an operation panel 7 is provided on the front surface of the housing 2 located on the free end side of the heater arm 3.
[0012]
The packaging area 4 is surrounded by a rectangular plate-shaped base plate 8 and a heater arm 3 that opens and closes so as to cover the upper surface of the base plate 8. The heater arm 3 is rotatably (open / close) supported by a base plate 8 by a support shaft 9 provided at a base end, and is locked in a closed state by a lock mechanism 10 provided on a side surface of the housing 2. It is configured to: As shown in FIGS. 2 and 3, the lock mechanism 10 is provided on a pin 11 provided on one side in the front end cover portion of the heater arm 3 so as to rotate on one side of the base plate 8. The hook 12 is configured to be locked by engagement. The operation of the hook 12 is performed by rotating the bent hook base end portion 12a by the solenoid 14 with the rotation shaft 13 as a fulcrum.
[0013]
The heater arm 3 is constantly urged in the opening direction by a spring 15 attached to the arm base end 3a near the support shaft 9, and when the hook 12 of the lock mechanism 10 is released from the pin 11, the heater arm 3 is turned on. It is configured to open automatically. When the heater arm 3 is closed so as to cover the packaging area 4 from above, the arm base end 3a comes into contact with the limit switch 16 to detect the closed state of the heater arm 3.
[0014]
A gas block 17 is provided near the open end (front portion) of the packaging area 4 so as to stand up from the base plate 8, and the upper end of the gas block 17 faces the inside of the packaging area 4. A plurality of gas nozzles 5 protrude substantially horizontally. The gas block 17 is airtightly connected to a suction system 20 of a vacuum pump 19 via a reduced-pressure driving chamber 18. As shown in FIGS. 4 and 5, a rubber holder 23 a that presses the outer surface of the bag when the gas nozzle 5 is inserted into the opening of the packaging bag 21 to prevent the packaging bag 21 from shifting, as shown in FIGS. , 23b to ensure the deaeration operation by the vacuum pump 19. The lower rubber retainer 23a is attached to the upper surface of a stay 24 disposed immediately below the nozzle of the gas block 17, and the upper rubber retainer 23b is connected to a stay 25 disposed along an upper sealing block 31b described later. It is attached to the lower surface. Further, a gas cylinder 26 for injecting an inert gas such as nitrogen into the degassed packaging bag 21 through the gas nozzle 5 is airtightly connected to one side of the gas block 17. Therefore, when the gas nozzle 18 is inserted into the opening of the packaging bag 21 and the vacuum pump 20 is operated in a state where the heater arm 3 is covered and locked, the air in the packaging bag 21 containing the packaged object 22 such as food is discharged by the gas nozzle. The gas in the gas cylinder 26 can be filled into the packaging bag 21 through the gas nozzle 5 when the degassing is completed. The operations of degassing and gas filling will be described later.
[0015]
A sealing mechanism 6 is provided near the rubber pressers 23a and 23b at the front of the packaging area 4, and at the back side of the packaging area 4 (rear part, that is, at the right side in FIG. 3), the packaging containing the article 22 to be packaged. A placement tray 29 provided with a butting plate 27 and a width regulating plate 28 for preventing movement of the bag 21 and for regulating and stabilizing the position of the packaging bag 21 to be sealed by the sealing mechanism 6. Are provided in a state of being inclined downward toward the inner side opposite to the gas nozzle 5. The packaging bag 21 has various sizes depending on the amount of the article 22 to be packaged, and the like, but the sealing position (sealing portion) by the sealing mechanism 6 is the same, and is located on the opposite side to the opening. The length to the closing portion (bottom), that is, the length of the storage portion for storing the packaged object 22 is different. Therefore, the configuration is such that the positions of the abutment plate 27 and the width regulating plate 28 can be adjusted according to the length of the storage portion of the packaging bag 21 and the bag width (width of the storage portion). Since the loading tray 29 is inclined upward from the back side of the packaging area 4 toward the sealing mechanism 6, when the packaging bag 21 containing the articles 22 to be packaged is placed on the loading tray 29. Then, the sealing portion (the band portion to be thermally welded) near the opening of the packaging bag 21 stably stops at a predetermined position of the sealing mechanism 6.
[0016]
Next, the sealing mechanism 6 will be described. The sealing mechanism 6 according to the present embodiment raises the lifting rod 30a of the lifting mechanism 30 having a lower end connected to the diaphragm 34 of the reduced-pressure driving chamber 18 provided at the front end of the base plate 8 in the packaging area 4. The lower sealing block 31a is fixed to the upper end of the lifting rod 30a, and the upper sealing block 31b is provided at the top of the cover portion of the heater arm 3 so as to face the lower sealing block 31a. These sealing blocks 31 a and 31 b are configured as heater blocks that are long in the width direction of the packaging area 4. A heater wire 32 is disposed along the width direction on the press-contact surfaces of the lower sealing block 31a and the upper sealing block 31b via a plate-like rubber member. Is raised and pressed against the upper sealing block 31b side. The diaphragm 34 and the lifting rod 30 a are urged downward by the return spring 33 in the decompression drive chamber 18. When the pressure in the decompression drive chamber 18 is reduced, the diaphragm 34 is opposed to the urging force of the return spring 33. As a result, the lower sealing block 31a is raised. Therefore, when the lower sealing block 31a rises, it can be pressed against the upper sealing block 31b while sandwiching the opening of the packaging bag 21. In this state, when the heater wire 32 is energized and heated, it is sandwiched. The packaging bag 21 can be sealed (sealed) by heat welding. Note that the gas filling machine 1 of the present embodiment is provided with an atmosphere release valve (not shown) for introducing the atmosphere into the decompression drive chamber 18, that is, opening the atmosphere. Therefore, when the air release valve is opened, the lower sealing block 31a is lowered by the urging force of the return spring 33 and returns to the original position.
[0017]
In addition, the pressing surfaces of the lower sealing block 31a and the upper sealing block 31b press and hold a non-heated portion (a portion not actively heated) located closer to the storage portion than the sealed portion of the packaging bag 21. The department is arranged. In the present embodiment, as one of the pressing sandwiching portions, a surface located on the storage unit side of the packaging bag 21 with respect to the heater wire 32 on one of the opposing press contact surfaces of the lower sealing block 31a and the upper sealing block 31b. Is provided with a projection 36. More specifically, the protrusion 36 shown in FIG. 5 is a metal wire fixed along the longitudinal direction of the block 31b to the end (the end opposite to the gas nozzle) of the press-contact surface of the upper sealing block 31b. It is constituted by. As described above, the metal wire 36 presses the non-heated portion of the packaging bag 21 closer to the storage portion than the sealing portion, raises the lower sealing block 31a, and presses the lower sealing block 31a against the upper sealing block 31b. Then, the rubber member mounted on the pressure contact surface of the lower sealing block 31a is depressed, and the non-heated portion of the packaging bag 21 sandwiched therebetween can be clamped with a stronger force than the other pressure contact surfaces. Therefore, the tensile force caused by the inflation force due to gas filling acts on the sealing portion of the packaging bag 21 sandwiched between the two pressure contact surfaces of the lower sealing block 31a and the upper sealing block 31b due to the strong clamping force. Can be prevented.
[0018]
As described above, when the opening of the packing bag 21 filled with gas is pressed by the lower sealing block 31a and the upper sealing block 31b and heated by the heater wire 32, the ends of the upper and lower sealing blocks 31a and 31b are heated. An inflating force acts to expand the packaging bag 21 up and down in the portion, but the metal wire 36 that presses the non-heated portion of the storage portion side of the packaging bag 21 closer to the pressurized surface of the upper sealing block 31b than the sealing portion of the packaging bag 21 is applied. Since the non-heated portion of the packaging bag 21 is sandwiched by the metal wires 36, the expansion force is not applied to the sealed portion which is easily expanded by heating, and the partial expansion of the packaging bag 21 is prevented. can do. That is, since the temperature of the non-heated portion does not increase, the strength of the synthetic resin sheet forming the bag is maintained, and the high strength portion receives the tensile force. Therefore, the pulling force does not act on the sealing portion whose strength has been reduced due to the heating, whereby the sealing operation can be reliably performed.
[0019]
The protrusion 36 is not limited to the above-described metal wire, and may be made of another material as long as it can press and hold a non-heated portion of the packaging bag 21 closer to the storage portion than the sealing portion. For example, the ridge may be ridged along the side edge of the plate-like rubber member of the press contact surface. Further, since the non-heated portion of the packaging bag 21 may be pressed and sandwiched, it may be provided on the press-contact surface of the lower sealing block 31a. Further, the sealing block may be separated into a portion provided with a heat source such as a heater wire and a portion having no heat source, and the projection 36 may be provided on the sealing block having no heat source. In short, the portion where the pressing and holding portion (projecting portion) is provided may be a portion where the heat at the time of heat welding is hardly transmitted to the packaging bag and which receives the inflation force caused by gas filling.
[0020]
Next, a series of sealing operations by the gas filling machine 1 will be described.
When the packaging bag 21 containing food or the like to be packaged is placed on the loading tray 29, and the heater arm 3 is placed and locked, the limit switch 16 is turned on, and control is performed by receiving a detection signal from the limit switch 16. The apparatus switches a flow path switching valve (not shown) to the vacuum pump 19 side, and degass the inside of the packaging bag 21 via the gas nozzle 5 (degassing step). Then, the control device switches the flow path switching valve to the gas cylinder 26 side to fill the packing bag 21 with the inert gas from the gas nozzle 5 (gas filling step). When the gas filling step is completed, the control device switches the flow path switching valve to the pressure reducing drive chamber 18 side, so that the lower sealing block 31a rises and the sealing portion of the packaging bag 21 is placed between the lower sealing block 31a and the upper sealing block 31b. At the same time, the protrusion 36 presses and holds the non-heated portion of the packaging bag 21 with strong pressure. Therefore, the tensile force due to the expansion force due to the filling of the inert gas only acts on the portion pressed and clamped by the projection 36, and is clamped between the lower sealing block 31a and the upper sealing block 31b. It does not act on the sealed portion of the packaging bag 21 thus obtained. In this state, the heater wire 32 is energized to generate heat, and this heat causes the sealing portion of the packaging bag 21 sandwiched between the lower sealing block 31a and the upper sealing block 31b to be pulled by the expansion force. Heat welding is performed without being affected by force (heat welding process). When the heat welding step is completed, the control device switches the flow path switching valve and opens the air release valve, so that the pressure in the decompression drive chamber 18 returns to the atmospheric pressure. The block 31a descends to complete the sealing step. Then, when the sealing process of the packaging bag 21 is completed, the control device excites the solenoid 14 of the lock mechanism 10, so that the hook 12 rotates and comes off the pin 11 to release the lock. Therefore, the packaging bag 21 can be taken out after raising the heat arm 3.
[0021]
In the above-described embodiment, the gas nozzle 5 not only performs gas filling but also functions as an element (inlet) of the deaeration means. However, the present invention is not limited to this, and the deaeration is separately performed. An intake port of the means may be provided so that the functions of the gas filling means and the deaeration means are separated. Further, the heater wire 32 may be disposed on one of the upper and lower sealing blocks 31a and 31b as long as the heater wire 32 is configured to transfer heat well. The gas to be filled from the gas nozzle 5 is not limited to an inert gas such as a nitrogen gas, but can be appropriately selected as needed.
[0022]
In the above-described embodiment, the packaging area is open to the atmosphere. However, the packaging area is set in a chamber so that the package can be vacuum-packaged, that is, provided with a sealing mechanism for heat-sealing and sealing. A gas filling machine that also serves as a vacuum packaging machine may be used.
[0023]
【The invention's effect】
As described above, the present invention has the following effects.
According to the first aspect of the present invention, a pressing and holding portion is provided on the press-contact surface of the sealing block to press and hold a non-heated portion located closer to the storage portion than the sealing portion of the packaging bag. Since the non-heated portion of the body is thermally welded while being held by the pressing / holding portion, the tensile force caused by the inflation force of the packing bag caused by gas filling is applied to the sealing portion of the packing bag pressed by the upper and lower sealing blocks. Never reach. Therefore, even when the sealing portion of the packaging bag is heated and softened during the thermal welding, it is possible to effectively prevent damage or poor welding due to the tensile force. Therefore, the sealing operation can be reliably performed.
[0024]
According to the invention as set forth in claim 2, the pressing and holding portion is formed on one of the opposing press contact surfaces of the upper and lower sealing blocks, and the protrusion is formed closer to the closed side of the packaging bag than the heater wire. Therefore, it has a simple structure, and it is possible to reliably and inexpensively prevent partial elongation of the packaging bag and to reliably perform the sealing operation.
[Brief description of the drawings]
FIG. 1 is a perspective view showing the overall appearance of a gas filling machine of the present invention.
FIG. 2 is a front view of the gas filling machine of the present invention.
FIG. 3 is a side view of the gas filling machine of the present invention.
FIG. 4 is a schematic view of a main part showing an internal structure of the gas filling machine of the present invention.
FIG. 5 is an enlarged view of a main part showing an example of a sealing mechanism in the gas filling machine of the present invention.
FIG. 6 is an enlarged view of a main part showing an example of a sealing mechanism in a conventional gas filling machine.
FIG. 7 is an enlarged view of a main part of a conventional gas filling machine showing a situation where the vicinity of a sealing portion partially extends when a packaging bag is sealed.
[Explanation of symbols]
REFERENCE SIGNS LIST 1 gas filling machine 2 housing 3 heater arm 3 a arm base end 4 packaging area 5 gas nozzle 6 sealing mechanism 7 operation panel 8 base plate 9 support shaft 10 lock mechanism 11 pin 12 hook 12 a hook base end 13 rotation Shaft 14 Solenoid 15 Spring 16 Limit switch 17 Gas block 18 Decompression drive chamber 19 Vacuum pump 20 Suction system 21 Packaging bag 22 Packed objects 23a, 23b Rubber holders 24, 25 Stay 26 Gas cylinder 27 Butting plate 28 Width regulating plate 29 Placed Tray 30 Elevating mechanism 30a Elevating rod 31a Lower sealing block 31b Upper sealing block 32 Heater wire 33 Return spring 34 Diaphragm 36 Pressing and holding part (projection, metal wire)

Claims (2)

A sealing mechanism for press-welding the opening of the packaging bag set in the packaging area with the upper and lower sealing blocks and heat welding; and a gas nozzle for filling the interior of the packaging bag with a gas. In a gas filling machine that fills the inside of the packaging bag with gas in a state of being stored in the package and seals the opening of the packaging bag by heat welding,
On the press-contact surface of the sealing block, a pressing holding portion for pressing and holding the non-heating portion located on the storage portion side of the sealing portion of the packaging bag is provided, and the non-heating portion of the packaging bag body is pressed by the pressing holding portion. A gas filling machine characterized by thermal welding while sandwiching. The pressing and holding portion is configured by a protrusion formed on the storage portion side of the packaging bag with respect to the heater wire on any one of the opposing press contact surfaces of the upper and lower sealing blocks. Item 2. A gas filling machine according to Item 1.

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