JP2001301703A - Top-seal-type packaging apparatus and method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress failures in sealing in a top-seal-type packaging apparatus. SOLUTION: The packaging apparatus 1 comprises an apparatus for covering an opening of a tray T with an upper portion opened with a stretch-wrap film and welding the film with a flange of the tray T. The packaging apparatus 1 includes a film carry mechanism, a lift mechanism 6, a roller and tray holding members 21 to 24. The lift mechanism 6 raises the tray T and presses the tray T against the stretch-wrap film. The roller comes into contact with the flange of the tray with which the stretch-wrap film is in contact to weld the film with the flange. The tray holding members 21 to 24 prevent the tray T from shifting in position when the stretch-wrap film is welded with the flange of the tray T.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a top-sealing type packaging apparatus and a top-sealing type packaging method, and more particularly, to a tray having an open upper portion, in which an object to be packaged is accommodated in the tray with a stretch film. The present invention relates to a top-sealing type packaging device for covering a tray and fusing a stretch film around an opening of a tray and a top-sealing type packaging method.

[0002]

2. Description of the Related Art Conventionally, an overlap method has been often used as a packaging method for fresh foods such as meat and fish, and processed foods such as side dishes. The overlap method is a method in which a package is placed on a tray and then the entire tray is wrapped with a film.

[0003] However, in the case of the overlap system, the tray and the whole package must be wrapped, and the film must be stacked for sealing.
A film several times as large as the planar size of the tray is required. Also, stack the film on the bottom of the tray,
Sealing is often performed by pressing the bottom of the tray against a hot plate, resulting in poor sealing performance.

[0004] On the other hand, a method of bringing the film only to the opening of the tray whose upper surface is open and welding the film around the opening of the tray (hereinafter referred to as a top seal method) is an overlap method. It has been adopted by some instead of the system. In this top seal method, the amount of film used can be reduced by half as compared with the case where the overlap method is employed.

[0005]

Conventionally, this top seal method is mainly used for packaging mushrooms such as shimeji. As a specific form, mainly, a form in which glue is applied to the side surface of the tray around the opening and the end of the film covered is adhered here, and a form in which the tray and the film larger than the plane area of the tray are bonded. There is a form in which heat welding is performed by sandwiching and applying heat together with pressure.

[0006] However, the above-mentioned top seal type requires a mold corresponding to the tray shape and tray size. For this reason, in the industry where multiple types of trays have to be packaged with a wide variety of trays and packages to be packaged,
In many cases, an overlap method is employed. The top seal method has the merit of reducing the amount of film used and improving the sealing performance of the seal, but is currently not adopted because molds must be prepared for trays of different shapes and sizes. It is often done.

In order to eliminate the disadvantages of the conventional top seal type packaging, the present applicant disclosed in Japanese Patent Application No. 11-137025 a method in which a heating roller was applied to a portion around the opening of a tray from above a film. Has proposed a device for performing heat sealing (heat welding) by rotating the heat generating roller around one axis. According to this apparatus, sealing can be performed without any problem as long as the tray has a certain size and shape in a certain range. In the conventional apparatus, it was necessary to change the mold when the tray was changed. However, in this apparatus, if the tray is within a certain range, the sealing can be continued without particularly changing the setup.

[0008] The applicant of the present application has filed Japanese Patent Application No. 11-154.
No. 616 proposes an apparatus for performing heat sealing by pushing up a tray covered with a stretch film against a rubber sheet heated by a heater. According to this apparatus, it is not necessary to prepare a mold for each tray having a different shape or size, and even if the tray changes, the sealing can be continued without changing the setup.

[0009] However, the above-mentioned Japanese Patent Application No. Hei.
In the apparatus proposed in Japanese Patent Application No. 11-154616, the tray receives a force from a heat generating roller or a rubber sheet during heat sealing. Then, the planar position of the tray is shifted, and there is a possibility that a difference in sealing pressure between the flange portions of the tray when heat sealing is performed. That is, in heat sealing, it is desirable to apply a heat roller or a rubber sheet to each part of the flange of the tray with as uniform pressure as possible, but if the center of the tray is shifted from the center of rotation of the heat roller or the center of the rubber sheet, There is a possibility that defective sealing may occur in some parts.

An object of the present invention is to provide a top-sealing type packaging apparatus / top-sealing type packaging method in which the opening of a tray having an open top is covered with a stretch film and the stretch film is welded to a portion around the opening of the tray to suppress poor sealing. It is in.

[0011]

According to a first aspect of the present invention, there is provided a top-seal type packaging apparatus in which an opening is covered with a stretch film in a state in which an article to be packaged is accommodated in the tray, and the tray is opened. This device welds a stretch film around the opening. This top-seal type packaging device includes a film supply mechanism, a lift mechanism, a heating element, and a tray holding member. The film supply mechanism supplies the stretch film above the tray. The lift mechanism raises the tray and presses the tray against the stretch film. The heat body contacts the periphery of the opening of the tray with which the stretch film is in contact, and welds the stretch film to the periphery of the opening of the tray. The tray holding member holds the tray when the stretch film is welded to a portion around the opening of the tray.

[0012] In the apparatus according to the present invention, the tray is pushed up against the stretch film supplied above the tray, and a heat body is brought into contact with a peripheral portion of the opening of the tray against which the stretch film is pressed, so that the stretch film is placed on the tray. To be welded. Here, when the stretch film is welded to the tray, a tray holding member is provided to hold the tray so that the position of the tray does not shift due to the contact of the heat. For this reason, the position of the tray with respect to the heating element can be kept at the optimum position, and the heating element hits the peripheral portion of the opening of the tray as designed. As a result, the occurrence of poor sealing due to the displacement of the tray is reduced.

Incidentally, the positional deviation of the tray includes a planar and linear positional deviation, a planar and rotational positional deviation,
Although there is a height shift, the tray holding member only needs to hold the tray so as to prevent at least one of these position shifts depending on the characteristics of the apparatus. Also,
The tray holding member may directly contact the tray and hold the tray, or may hold the tray indirectly by means such as suction.

According to a second aspect of the present invention, there is provided the packaging apparatus according to the first aspect, wherein the tray holding member further includes a tray displaced when the tray is raised and pressed against the stretch film. prevent. Here, the tray holding member holds the tray not only when the stretch film is welded to the periphery of the opening of the tray, but also when the tray is raised and pressed against the stretch film, thereby preventing the tray from being displaced. . For this reason, the displacement of the tray due to the contact with the stretch film can be prevented, and the sealing failure can be further suppressed.

According to a third aspect of the present invention, there is provided a packaging apparatus according to the first or second aspect, wherein the tray holding member contacts a side surface of the tray to prevent the tray from being displaced in a planar manner. A top seal type packaging device according to a fourth aspect is the packaging device according to any one of the first to third aspects, further comprising a tray mounting / holding mechanism. The tray mounting and holding mechanism mounts the tray and is transferred to a lift mechanism together with the tray. The tray holding member is included in the tray mounting and holding mechanism. Further, the lift mechanism raises the tray by lifting the tray mounting and holding mechanism.

Here, the tray is transferred to the lifting mechanism by transferring the tray mounting and holding mechanism to the lifting mechanism in a state where the tray is placed on the tray mounting and holding mechanism and the position of the tray is prevented by the tray holding member. The tray is lifted by lifting the tray mounting / holding mechanism by the lift mechanism. Therefore, the displacement of the tray is prevented both during transfer to the lift mechanism and during lifting by the lift mechanism. Therefore, the tray is sealed (welded) by the heating element at the designed position, and a more stable seal is achieved.

A top seal type packaging apparatus according to a fifth aspect is the packaging apparatus according to any one of the first to fourth aspects, wherein the tray mounting and holding mechanism urges the tray holding member toward the tray. Use to adjust the tray position. Here, the tray mounting / holding mechanism has a role of adjusting the planar position of the tray (for example, performing centering of the tray) in addition to the role of preventing the tray from being displaced by the tray holding member. . At the time of adjusting the planar position of the tray, the tray holding member is urged toward the tray. The means for urging the tray holding member toward the tray includes, for example, a spring, an electric motor, an air cylinder, a hydraulic cylinder, and the like.

As described above, if the position of the tray is adjusted by the tray holding member and the tray is held by the tray holding member so as to prevent the tray from shifting, the transfer of the tray from the position adjusting unit to the holding unit is achieved. This eliminates the need for such a structure and simplifies the structure. A top seal type packaging device according to a sixth aspect is the packaging device according to any one of the first to third aspects, further comprising a position detection unit and a control unit. The position detecting means detects a position state of the tray when the tray is transferred to the lift mechanism.
The control unit causes the tray holding member to correct the position deviation of the tray based on the detection result of the position detection unit.

Here, the displacement of the tray is corrected by the tray holding member, and the tray is held by the tray holding member so as to prevent the displacement of the tray. As described above, since the tray holding member is used for correcting displacement and preventing subsequent displacement, the structure of the apparatus is simplified. A top seal type packaging device according to a seventh aspect is the packaging device according to any one of the first to third aspects, further comprising an urging unit and a control unit. The urging means urges the tray holding member toward the tray. The control unit controls the urging force of the urging means.

In this case, the tray holding member is urged toward the tray to hold the tray, thereby preventing the tray from being displaced. However, in order to adjust the holding force of the tray, the urging means is required. The configuration is such that the biasing force is controlled by the control unit. Therefore, the holding force for holding the tray can be changed depending on parameters such as the hardness of the tray and the material of the tray. For example, control can be performed such that the holding force is weakened in the case of a soft tray, and the holding force is increased in the case of a hard tray. Thus, it is possible to reliably prevent the tray from being displaced, and to suppress a problem that the tray is deformed and a sealing failure occurs.

According to an eighth aspect of the present invention, there is provided a top seal type packaging apparatus according to the seventh aspect, further comprising an urging force detecting means. The urging force detecting means detects the urging force of the urging means. The control unit controls the urging force of the urging means based on the detection result of the urging force detecting means. Here, since the urging force detecting means is provided, the urging means can be controlled while confirming the actual urging force, that is, the holding force of the tray. This prevents the tray, which is not a rigid container, from being crushed by an excessively strong urging force, and the tray is held with a holding force that matches the characteristics of the tray.

A top seal type packaging apparatus according to a ninth aspect is the packaging apparatus according to the seventh aspect, wherein the control unit includes an urging means corresponding to at least one of the characteristics of the tray and the characteristics of the stretch film. Control power. Here, the urging force of the urging means, that is, the holding force of the tray, can be adjusted according to the characteristics of the tray such as the hardness of the tray and the material of the tray, or the characteristics of the stretch film such as the thickness and the material.

According to a tenth aspect of the present invention, there is provided a top seal type packaging apparatus, wherein an opening is covered with a stretch film in a state where an object to be packaged is accommodated in the tray with respect to the tray having an upper opening.
This device welds a stretch film around the opening around the tray. This top seal type packaging device includes a film supply mechanism, a lift mechanism, a heating element, and a position adjustment mechanism. The film supply mechanism supplies the stretch film above the tray. The lift mechanism raises the tray and presses the tray against the stretch film.
The heat body contacts the periphery of the opening of the tray with which the stretch film is in contact, and welds the stretch film to the periphery of the opening of the tray. The position adjusting mechanism adjusts the planar position of the tray before the tray is pressed against the stretch film.

In the apparatus according to the present invention, the tray is pushed up with respect to the stretch film supplied above the tray, and a heat is brought into contact with the periphery of the opening of the tray against which the stretch film is pressed, so that the stretch film is placed on the tray. To be welded. Here, in order to position the tray at an optimum position with respect to the heating element when the stretch film is welded to the tray, a position adjusting mechanism for adjusting the planar position of the tray before the tray is pressed against the stretch film is provided. For this reason, the tray adjusted in position to the optimal position hits the stretch film and is welded to the stretch film by the heat. As described above, since the position of the tray with respect to the heating element is adjusted to the optimum position, the occurrence of seal failure due to the displacement of the tray is reduced.

[0025] In the top seal type packaging method according to the eleventh aspect, the opening is covered with a stretch film in a state in which an article to be packaged is accommodated in the tray with respect to the tray having an open top.
In this method, a heat body is applied to the periphery of the opening of the tray to weld the stretch film. This top-seal type packaging method includes a film supply step, a position adjustment step, a lift step, and a welding step. In the film supply process,
Supply the stretch film above the tray. In the position adjusting step, the planar position of the tray is adjusted. In the lift step, the tray is raised and the tray is pressed against the stretch film. In the welding process, a heating element is brought into contact with the periphery of the opening of the tray where the stretch film is in contact,
The stretch film is welded around the opening of the tray.

[0026]

DESCRIPTION OF THE PREFERRED EMBODIMENTS <Outline of Apparatus> FIGS. 1 and 2 show a top seal type packaging apparatus according to an embodiment of the present invention. The packaging apparatus 1 shown here covers the upper opening o of the tray T containing fresh foods such as meat and fish and processed foods such as side dishes with a stretch film Fm (see FIG. 3), as shown in FIGS. 4 and 7. A flange (opening peripheral portion) f around the opening o of the tray T and a stretch film Fm
Are sealed by heat welding.

<Structure of Apparatus> This packaging apparatus 1 includes a frame 1a, a tray mounting / holding mechanism 2 for holding a tray T, four rollers (heat bodies) 3 located above the tray mounting / holding mechanism 2, A film transport mechanism 5 for supplying the stretch film Fm between the tray mounting and holding mechanism 2 and the roller 3, a lifting mechanism 6 for raising and lowering the tray mounting and holding mechanism 2, and a roller vertical moving mechanism 7 for mainly moving the roller 3 up and down. ,
A roller rotating mechanism 8 having two rotating axes and rotating the roller 3 around each of the rotating axes 81a and 81b; a stretching mechanism 9 for stretching the stretch film Fm between the tray placing and holding mechanism 2 and the roller 3; The control unit 10 includes a control unit 10 that performs control.

<Structure of Each Part> (Tray Placement / Holding Mechanism) The tray placement / holding mechanism 2 holds and holds the tray T on its upper surface, and is moved up and down by a lift mechanism 6. Further, the tray mounting / holding mechanism 2 can be pulled out from the position shown by the solid line in FIG. 2 to the position shown by the two-dot chain line, and can be pushed in reverse. This horizontal movement is performed manually or by driving means (not shown).

The operation of placing the tray T on the tray placing and holding mechanism 2 may be performed manually by an operator, or may be automatically carried out from a separately prepared tray T transporting device. You may make it. The detailed configuration of the tray mounting and holding mechanism 2 will be described later in detail. (Roller) The roller 3 is a cylindrical member, and is rotatably supported by a roller supporting portion 71 of a roller up / down moving mechanism 7 described later. On the surface of the roller 3, a layer softer than other portions is formed in order to reduce frictional resistance with the stretch film Fm.
Specifically, the surface of the roller 3 is formed of an elastic material such as resin or synthetic rubber, and even when the surface of the flange f of the tray T has minute irregularities, the compression bonding between the stretch film Fm and the flange f can be performed. It has been secured.

As shown in FIG. 5, two rollers 3 are provided for pivot shafts 81a and 81b of a roller pivot mechanism 8, which will be described later. FIG. 5 is an arrangement diagram when the roller 3 is viewed from below. Thus, roller 3
Are arranged in plan view as shown in FIG. 5, and are attached to the respective pivot shafts 81a and 81b at an angle of about 110 °.

Further, these rollers 3 are shown in FIGS.
As shown in FIG. 7, the roller T is supported by the roller support 71 in a state where it is inclined with respect to the upper surface of the tray T parallel to the horizontal plane when viewed from the side. This inclination is set such that the end of the roller 3 on the side of the rotating shafts 81a and 81b is at a position higher than the other end. The roller 3 has a roller 3 inside.
Is disposed. The specifications of this heater are the tray T to be sealed and the stretch film Fm.
Considering that it is necessary to input energy that can recover the amount of heat taken away by the seal in a short time,
Appropriate specifications have been selected.

(Film transport mechanism) Film transport mechanism 5
Is a mechanism that unwinds the stretch film Fm between the tray placing and holding mechanism 2 and the roller 3 in the lowered state, and winds up the stretch film Fm that has been partially cut out by fusing accompanying a seal. As shown in FIG. 1, the film transport mechanism 5 includes a film setting section 51.
, A film winding section 53 and a film transport section 52. The film setting section 51, the film transport section 52, and the film winding section 53 are supported by the frame 1a, respectively.

The film setting section 51 is composed of a member that rotatably supports the film roll R of the stretch film Fm, and holds the film roll R and serves as a supply source of the stretch film Fm. The film setting section 51 has a core support member 51a that can move up and down and a support roller 51b that supports the film roll R obliquely below. The film roll R is supported by the core support member 51a and the support roller 51b, and a feeding roller 52a of a film transport unit 52 described later (see FIG. 1).

The film take-up section 53 is provided to take up the remaining stretch film Fm, part of which is taken out by packaging (top seal) of the tray T, and has a take-up shaft 53a. This winding shaft 5
3a is rotated by a belt 53b hung on a motor 52c described later. The detailed structure of the winding shaft 53a will be described later.

The film transport section 52 includes a feeding roller 5
2a, a motor 52c for rotating the feeding roller 52a via a belt 52b, and a film supporting roller 52a.
d. The stretch film Fm drawn from the film roll R is sent to the film winding unit 53 side by the rotation of the feeding roller 52a. In addition, the take-up shaft 53a rotates together with the pay-out roller 52a with the rotation of the motor 52c, so that the stretch film Fm is taken up by the take-up shaft 53a while being fed from the film roll R. The rotation speed of the winding shaft 53a is set to be higher than the rotation speed of the feeding roller 52a. For this reason,
The stretch film Fm is in a state where a tension is applied along the transport direction. As a result, transport without slack is performed.

The feeding roller 52a has a gripping property with respect to the stretch film Fm, and can feed the stretch film Fm by a predetermined amount while suppressing a slip. More specifically, a one-way clutch (not shown) is provided to apply a mirror finish to the surface of the feeding roller 52a to prevent the feeding roller 52a from rotating in the reverse direction. As shown in FIG. 1, the feeding roller 52a
The support roller 51b is arranged symmetrically with respect to the support roller 51b. The distance between the feeding roller 52a and the supporting roller 51b is set smaller than the diameter of the core material of the film roll R, so that the film roll R does not fall off between the rollers 52a and 51b. I have.

The film support roller 52d is arranged near the film take-up section 53, and is set so that the upper surface thereof coincides with the lower surface of the feeding roller 52a (see FIG. 1). Therefore, the horizontal state of the portion of the stretch film Fm being transported, which is located between the feed roller 52a and the film support roller 52d, is maintained.

(Stretch Mechanism) The stretch mechanism 9
Of the stretch film Fm continuing from the film setting section 51 to the film winding section 53, the feeding roller 5
This is a mechanism that grips both side ends of a horizontal portion between the film support roller 2a and the film support roller 52d and stretches the stretch film Fm in the width direction (the left-right direction in FIG. 2). The stretch mechanism 9 includes a pair of film grippers 91a and 91b extending in the film transport direction, and a stretch drive unit 93 (see FIG. 9) for moving these in a direction perpendicular to the film transport direction (left-right direction in FIG. 2). have.

The film holding portions 91a and 91b hold the stretch film Fm by sandwiching the stretch film Fm from above and below, and are turned ON / OFF using solenoids 92a and 92b (see FIG. 9). Further, a rubber (or resin) pad having a large coefficient of friction is attached to a portion in contact with the stretch film Fm from above, thereby preventing the film gripping portions 91a and 91b and the stretch film Fm from slipping. .

The stretch driving section 93 includes a motor 93a.
(See FIG. 9), and is composed of a guide rail, a sprocket, a chain, and the like, and moves the film grippers 91a and 91b in the left and right directions in FIG. (Lift Mechanism) The lift mechanism 6 is a mechanism for pushing up the tray mounting and holding mechanism 2 holding the tray T with respect to the stretch film Fm as shown in FIG. The lift mechanism 6 includes a driving motor 61, a large gear 62 pivotally supported by the frame 1a, a link member 63, a lever 64 having one end pivotally supported by the frame 1a at a fulcrum 64a, and a tip end of the lever 64 rotatably. It is composed of a mounted disk member 65 and the like.

When the drive motor 61 operates, the large gear 62 rotates via a gear fixed to the motor shaft. Then, the lever 64 is moved to the fulcrum 64a via the link member 63.
Around the center. Thereby, the tray mounting and holding mechanism 2 whose lower surface is supported by the disk member 65 moves up and down (see FIGS. 2 and 3). In addition, the tray mounting and holding mechanism 2
Is guided by a vertical guide rail 69,
It moves in the vertical direction by the operation of the lift mechanism 6.

(Roller Up / Down Moving Mechanism) The roller up / down moving mechanism 7 is a mechanism for changing the height position of the roller 3, and as shown in FIG. A link mechanism 72, a pressing plate 73, a lever mechanism 74 for applying a force to the pressing plate 73 from above, and a motor 75 for operating the lever mechanism 74 are provided.

The roller supporting portion 71 supports the roller 3 so that the roller 3 is inclined as shown in FIGS. 1 and 2 in a side view. 1 and 2 in the roller 3 shown in FIGS.
The dotted line is the rotation axis of the roller 3. Link mechanism 72
One end supports the roller supporting portion 71 with a pin, and the other end is pressed down by the pressing plate 73. When the other end of the link mechanism 72 is pressed down by the pressing plate 73, one end is raised as shown in FIGS. 1 and 2, and the roller support 71 and the roller 3 are also raised. Become. On the other hand, the holding plate 73 is
When no force is applied to the roller 3, the roller support 71 and the roller 3
The other end of the link mechanism 72 is lowered by its own weight or the like (see FIGS. 2 and 4).

A force is applied to the pressing plate 73 from above by a lever mechanism 74 operated by a motor 75. As shown in FIGS. 2 and 4, the outer peripheral portion of the pressing plate 73 is in a state of being placed on a rolling element that is supported at the other end of the link mechanism 72. (Roller turning mechanism) The roller turning mechanism 8 is a mechanism that turns the roller 3 and the roller supporting portion 71 and the link mechanism 72 that support the roller 3 by a predetermined angle during seal packaging. The roller turning mechanism 8 mainly includes a first turning shaft 81a,
It comprises a second turning shaft 81b and a motor 82 for rotating both turning shafts 81a and 81b.

The lower end of the first turning shaft 81a is fixed to a base member 79 supporting two link mechanisms 72, and the upper end of the first turning shaft 81a is engaged with the main gear 83 via a gear. The main gear 83 is connected to the motor 82 by a pulley and a belt 84, and is rotated by the operation of the motor 82. The lower end of the second turning shaft 81b is fixed to a base member 79 supporting another two link mechanisms 72 (a member different from the base member 79 to which the first turning shaft 81a is fixed). The upper end of the second turning shaft 81b is meshed with the main gear 83 via a gear (see FIG. 5).

When the motor 82 rotates the turning shafts 81a and 81b by a predetermined angle under the control of the control unit 10, each roller 3 turns by a predetermined angle around the first turning shaft 81a or the second turning shaft 81b. (See FIG. 6).
In FIG. 6, for easy understanding, the roller 3 connected to the first turning shaft 81a is connected to the rollers 3a and 3b.
And the rollers 3 connected to the second turning shaft 81b are indicated as rollers 3c and 3d. In FIG. 6,
The position of the roller 3 before turning is shown by a solid line, and the position of the roller 3 after turning is shown by a dotted line.

(Control Unit) As shown in FIG.
Is equipped with a CPU 11 as a control unit main body,
A ROM 12 and a RAM 13 are mounted as a main storage unit controlled by the CPU 11. Further, the control unit 10
It has a display control circuit 15a for controlling data display on a display 15 for displaying to an operator, a keyboard circuit 16a for taking in key input data from a keyboard 16 for receiving input from the operator, and the like.

The controller 10 has a tray master file 14a in the HDD (hard disk) 14. The tray master file 14a stores data such as tray size, tray material, tray shape, and the like for each tray number. On the other hand, a data area for storing the tray information called from the tray master file 14a is formed in the RAM 13.

Then, CPU 11, ROM 12, RAM
The HDD 13 and the circuits 15a and 16a are interconnected via bus lines such as an address bus and a data bus. This control unit 10, as shown in FIG.
It is connected to driving means such as a motor of each mechanism and the heater 31, and controls these movements.

<Operation Control of Packaging Apparatus> (Overall Control) When the tray T containing packages such as food is placed on the tray placing and holding mechanism 2 which is drawn out to the position shown by the two-dot chain line in FIG. The tray mounting / holding mechanism 2 is horizontally moved below the rollers 3 by manual operation or by driving means (not shown).

When moving below the roller 3, the tray mounting / holding mechanism 2 centers the tray T and holds the side surface of the tray T from all sides. The operation of the tray mounting and holding mechanism 2 will be described later in detail.
The control unit 10 calculates an amount of feeding the stretch film Fm by the film transport mechanism 5 according to the tray T.
More specifically, the control unit 10 controls the keyboard 1
The tray size and the tray material stored in the tray master file 14a are called from the tray number input from 6, and the feeding amount of the stretch film Fm is calculated. Note that the payout amount of the stretch film Fm may be stored in the tray master file 14a.

When the stretch film Fm is fed out from the film transport mechanism 5, the control section 10 operates the stretch mechanism 9 to stretch the stretch film Fm in the width direction (the left-right direction in FIG. 2). Thereby, tension is applied to the stretch film Fm in the width direction, and the stretch film Fm is in a state without wrinkles. Next, the control unit 10 operates the lift mechanism 6 to lift the tray placing / holding mechanism 2 holding the tray T. Following this, the tray T pushes up the stretch film Fm and stops (see FIG. 3).

Next, the control unit 10 controls the motor 75 to release the downward urging of the pressing plate 73 by the lever mechanism 74, and opens the link mechanism 72. Then, the roller 3 descends until it comes into contact with the tray T by its own weight or the like (see FIG. 4). Since these rollers 3 are independent from each other, each roller 3 comes into contact with the tray T with substantially the same pressure.

Next, the controller 10 controls the motor 82 to rotate the turning shafts 81a and 81b by a predetermined angle. The predetermined angle is set to 110 ° here so that the entire flange f of the tray T is sealed by any of the rollers 3a to 3d (see FIG. 6). Pivot shaft 81a,
When the roller 3 rolls on the tray T from above the stretch film Fm by rotating around the center 81b, the roller 3 thermally welds the flange f of the tray T and the stretch film Fm.

FIG. 7 shows an enlarged view of the vicinity of the contact portion between the rollers 3 when the roller 3 moves along the periphery of the tray T. The tray T is in a state where the opening o is covered with the stretch film Fm. The stretch film Fm is pressed against the flange f of the tray T. Then, the roller 3 hits the contact portion between the stretch film Fm and the flange f obliquely from above to apply heat and force. By these heat and force, the stretch film F
m and the flange f are thermally welded. At this time, heat and force concentrate on the stretch film Fm at the edge portion of the tray T (here, the outer portion of the top of the flange f on which the roller 3 is in contact), so that the stretch film Fm is at the edge portion of the tray T. Is melted and separated (see FIG. 8). The control unit 10 rotates the roller 3 at such a speed that the stretch film Fm and the flange f are thermally welded and the stretch film Fm is blown off outside the joint portion by the thermal welding.

After the sealing of the stretch film Fm on the tray T by the roller 3 is completed, the roller 3 is pulled up and the tray T is lowered, and then the tray T packed and sealed is taken out from the drawn tray mounting and holding mechanism 2. Then, move to the next cycle. When the tray mounting and holding mechanism 2 is pulled out from the position shown by the solid line in FIG. 2 (below the roller 3) to the position shown by the two-dot chain line, the holding of the tray T is released as described later.

When the process proceeds to the next cycle, the stretch film Fm, which has been partially cut out by hot-sealing by the seal wrapping of the tray T, is wound around the winding shaft 53a. At this time, the rotation of the motor 52c rotates the film supporting roller 52d and the feeding roller 52a, so that the winding of the stretch film Fm for the next cycle (supply of the stretch film Fm below the roller 3) is performed simultaneously with the winding. Will be

The width of the stretch film Fm is set so as to be at least larger than the width of the tray T when stretched by the stretching mechanism 9.
The continuity of the stretch film Fm is not broken by the seal wrapping of the tray T (pulling out of the stretch film Fm), and the trouble that the film winding unit 53 cannot take up the film does not occur. Further, if the amount of stretching the stretch film Fm is controlled to be changed, the trays T of various sizes can be sealed and wrapped with one size of film width, and the stretch film Fm can be sealed.
m can be saved.

<Detailed Configuration of Tray Placement / Holding Mechanism>
The detailed configuration of the tray mounting and holding mechanism 2 will be described. As shown in FIGS. 10 to 17, the tray mounting and holding mechanism 2 mainly includes a casing 20 and first to fourth tray holding members 21.
To 24, a left and right guide shaft 25 and a front and rear guide shaft 26,
Link mechanism 27a, 27b, coil spring 27
d and 27e, first and second rollers 28a and 28b, and a vertically moving guide member 29b.

The casing 20 moves forward and backward on the longitudinal movement guide member 29a while supporting the other members, and is guided by the vertical movement guide member 29b by the operation of the lift mechanism 6 to move the vertical guide rail 69. Move up and down along. Further, a fixed support plate 20a for mounting the tray T is fixed to the casing 20. As shown in FIG. 14, the fixed support plate 20a is formed with a notch for avoiding interference with the moving first to fourth tray holding members 21 to 24.

First and second tray holding members 21 and 22
Is a member that performs centering (position adjustment) of the tray T in the left-right direction, and also sandwiches the tray T from both left and right sides to prevent the tray T from being displaced in the left-right direction. At the upper portions of the first and second tray holding members 21 and 22, contact portions 21 that contact the left and right side surfaces of the tray T from the side are provided.
a, 22a are formed. Also, the contact portions 21a, 2
2a, the tray lower surface support plate 2
1b and 22b extend. Tray lower support plate 21b,
22b enters between the tray T and the fixed support plate 20a when the tray mounting and holding mechanism 2 is moved horizontally below the roller 3 (see FIG. 10).

Third and fourth tray holding members 23, 24
Is a member that performs centering (position adjustment) of the tray T in the front-rear direction, and prevents the tray T from being displaced in the front-rear direction by sandwiching the tray T from both front and rear sides. Above these third and fourth tray holding members 23, 24, contact portions 23 that come into contact with the front and rear side surfaces of the tray T from the side are provided.
a and 24a are formed.

Further, the first and second tray holding members 21,
22 is supported by a link mechanism 27a, and the third and fourth tray holding members 23 and 24 are supported by a link mechanism 27b so as to move left and right and back and forth symmetrically with respect to the central axis 27c. The first and second tray holding members 21 and 22 are connected to the casing 20 via the left and right guide shafts 25.
And the third and fourth tray holding members 23,
Reference numeral 24 is supported by the casing 20 via a front and rear guide shaft 26. Both ends of the left and right guide shafts 25 and the front and rear guide shafts 26 are fixed to the casing 20.

The link mechanism 27a is formed symmetrically with the center shaft 27c as a fulcrum, and both ends are supported by the lower portions of the first and second tray holding members 21 and 22. As shown in FIG. 17, the link mechanism 27a is urged by a coil spring 27d so that both ends receive a force directed inward. The link mechanism 27b has a central shaft 27c.
Are formed symmetrically with the fulcrum as a fulcrum, and both ends are pivotally supported by lower portions of the third and fourth tray holding members 23 and 24.
As shown in FIG. 17, the link mechanism 27b is urged by a coil spring 27e so that both ends receive a force directed inward.

The center shaft 27c is arranged so as to come to the center of the tray T when the tray mounting and holding mechanism 2 is lifted by the lift mechanism 6. Specifically, the central axis 27c is disposed so as to be on a straight line connecting the two turning axes 81a and 81b in a plane. Although the coil springs 27d and 27e are used here, it is also possible to use an electric motor, a pneumatic cylinder, a hydraulic cylinder, or the like as the urging means.

The first roller 28a is a rotating body regulated by the first roller guide member 1c integrated with the frame 1a, and is provided at a tip end of a member extending from the lower portion of the first tray holding member 21 to the back in the front-rear direction. It is pivoted. 2nd roller 28b
Is a rotating body regulated by a second roller guide member 1d integrated with the frame 1a, and the fourth tray holding member 2
4 is supported by the tip of a member extending rightward from the lower part of the member 4.

The vertical movement guide member 29b is
0 and is engaged with the vertical guide rail 69 so as to be vertically movable. <Operation of Tray Placement / Holding Mechanism> Next, the operation of the tray placement / holding mechanism 2 will be described in detail. FIGS. 10, 12, 14A, and 1 show the state in which the tray mounting and holding mechanism 2 is pulled out.
5, and FIG. 17 (a) show the state in which the tray placing / holding mechanism 2 is horizontally moved below the roller 3 (pushed state) in FIG. 11, FIG. 13, FIG. 14 (b), FIG. 17
(B).

In the pulled-out state, the tray T is placed on the fixed support plate 20 a on the upper part of the casing 20, and the tray placing and holding mechanism 2 is pushed below the rollers 3. Then, the tray mounting / holding mechanism 2 is placed on the forward / backward movement guide member 29a and horizontally moves backward. The longitudinal movement guide member 29a is a pair of horizontal guide rails 1b integrated with the frame 1a.
, So as to be able to move back and forth.

When the tray mounting / holding mechanism 2 is pushed in, the first roller 28a regulated by the first roller guide member 1c gradually moves rightward along the slope of the first roller guide member 1c. When the first roller 28a comes off the first roller guide member 1c, there is no longer any restriction on the first roller 28a by the first roller guide member 1c. As a result, the first and second tray holding members 21 and 22 are moved by the urging force of the coil spring 27d as shown in FIGS.
Move inward as shown in (b). At this time, the first and second tray holding members 21 and 22 move horizontally along the left and right guide shafts 25. Then, the contact portions 21a and 22a of the first and second tray holding members 21 and 22 come into contact with the side surfaces of the tray T to hold the tray T from both left and right sides, and the first and second tray holding members 21 and 22 stops moving.

When the tray mounting / holding mechanism 2 is pushed in, the second roller 28b regulated by the second roller guide member 1d comes off the second roller guide member 1d, and the second roller 28b is released.
The regulation of the roller 28b by the second roller guide member 1d is eliminated. Thus, the third and fourth tray holding members 23 and 24 are moved inward as shown in FIGS. 14B and 17B by the urging force of the coil spring 27e. At this time, the third and fourth tray holding members 23, 2
4 moves horizontally along the front / rear guide shaft 26. Then, the contact portion 2 of the third and fourth tray holding members 23, 24
3a and 24a are in contact with the side surface of the tray T to hold the tray T from both front and rear sides.
The movement of the tray holding members 23 and 24 stops.

As described above, when the tray mounting and holding mechanism 2 is pushed below the roller 3, the first to fourth tray holding members 21 to 24 move toward the central shaft 27c to center the tray T. At the same time, the four side surfaces of the tray T are held by the contact portions 21a to 24a (see FIGS. 11 and 14B). The tray mounting and holding mechanism 2 is lifted vertically upward along the vertical guide rail 69 by the operation of the lift mechanism 6 while holding the tray T.

<Features of the Packaging Apparatus of the Present Embodiment> (1) In the conventional overlap type stretch packaging apparatus, since the stretch film is folded under the tray, not so high positional accuracy is required. However, in the case of the top seal type packaging apparatus as in the present embodiment, the positional accuracy of the tray T with respect to the roller 3 is required.

Therefore, in the packaging apparatus 1 of the present embodiment, when the stretch film Fm is welded to the tray T, the position of the tray T is not shifted by the contact of the roller 3 and the stretch film Fm Fm
So that the position of the tray T does not shift when
Tray T by first to fourth tray holding members 21 to 24
Holding the sides. For this reason, the position of the tray T with respect to the turning range of the roller 3 can be maintained at an optimum position, and the roller 3 comes into contact with the flange f as designed. As a result, the occurrence of defective sealing due to the displacement of the tray T is reduced.

(2) Further, in the packaging apparatus 1, when the tray T is held by the first to fourth tray holding members 21 to 24, the tray holding members 21 to 24 adjust the position of the tray T (centering). The tray mounting / holding mechanism 2 is configured using the link mechanisms 27a and 27b and the coil springs 27d and 27e. For this reason, the tray T centered on the central axis 27c hits the stretch film Fm while being held,
The roller 3 is welded to the stretch film Fm.

(3) In the packaging apparatus 1, the tray T is placed on the tray placing and holding mechanism 2 so that the tray holding members 21 to 2
In this state, the entire tray mounting and holding mechanism 2 is lifted by the lift mechanism 6 while the centering and holding of the tray T are performed by the lift mechanism 4. Therefore, the displacement of the tray T can be suppressed both during transfer to the lift mechanism 6 (when the tray placing / holding mechanism 2 is pressed) and during lifting by the lift mechanism 6.

(4) In the packaging apparatus 1 of this embodiment, since the roller 3 rotates during heat sealing, a force (a force including a horizontal component) that moves the tray T is applied to the tray T. Therefore, the effect of holding the tray T by the tray holding members 21 to 24 at the time of heat sealing is particularly large.

(5) In the packaging apparatus 1 of the present embodiment, the tray lower surface support plates 21b and 22b supporting the left and right ends of the lower surface of the tray T together with the abutment portions 21a and 22a correspond to the left and right width of the tray T. Move (see FIG. 14). That is, the size of the portion that supports the lower surface of the tray changes depending on the size of the tray T. This avoids interference between the roller 3 and the member supporting the lower surface of the tray during heat sealing. Further, interference between the stretch film Fm and a member supporting the lower surface of the tray is also avoided.

[Other Embodiments] (A) In the above embodiment, the tray T is centered at the stage where the tray mounting / holding mechanism 2 is pushed horizontally below the roller 3, but the centering is not necessarily performed at this stage. However, the tray T may be positioned (centered) at any stage as long as the tray T hits the stretch film Fm, such as when the tray T is raised.

(B) In addition to the configuration of the above-described embodiment, a pressure sensor may be provided on the contact surface of the contact portions 21a to 24a of the tray holding members 21 to 24 with the tray T, or the tray holding members 21 to 24 A proximity switch that can detect contact with the tray T may be provided, so that it can be detected that the tray holding members 21 to 24 have hit the side surface of the tray T. In this manner, even if the tray T is not properly held, it is possible to detect the failure and stop the packaging process as an error.

Alternatively, the movement amount of the tray holding members 21 to 24 may be stored in the tray master file 14a for each type of tray, and the tray holding members 21 to 24 may be moved according to the stored movement amount. (C) In the above embodiment, the side surfaces of the tray T are held by the tray holding members 21 to 24 to mainly prevent the tray T from being shifted in a planar manner. A member that regulates vertical displacement may be provided. Thereby, when the tray T is raised, it is possible to suppress the tray T from rising and shifting the position of the tray T.

Specifically, the lower surface of the tray T is sucked.
Alternatively, it is conceivable to provide a member that locks the flange f of the tray T from above. However, when the flange f is pressed from above, it is necessary to remove the member at the time of heat sealing, so that an avoidance mechanism is also required. (D) In the above-described embodiment, a method in which the entire flange f of the tray T is scanned by rotating the roller 3 is adopted. However, a method in which the tray T is pressed against the dome-shaped elastic heating sheet from below is adopted. The present invention is also applicable to the adopted packaging device.

Also in this case, by preventing the displacement of the tray T, a stable seal can be performed. (E) In the above embodiment, the tray mounting and holding mechanism 2 has both the centering function and the tray holding function.
The lift mechanism 6 may be provided with a tray support or a tray holding member, and a centering function may be separately provided in a path for carrying in the lift mechanism 6.

For example, as shown in FIG. 18, the centering of the tray T in the front-rear direction is performed by controlling the amount of pushing of the pusher 110, and the left-right moving belt conveyor 115 provided in the middle of the carry-in path is used to move the tray T in the left-right direction. Centering may be performed. At this time, the width and depth of the tray T may be detected by a CCD camera or a plurality of sensors, and the pusher 110 and the belt conveyor 115 may be controlled accordingly. As a specific method for disposing the sensors, a plurality of sensors of a reflection type or the like are disposed in the width direction of the tray T, and a sensor for monitoring a direction orthogonal to the transport direction (front-back direction) of the tray T is disposed. Conceivable.

Further, as shown in FIG.
The centering in the front-rear direction can be performed by controlling the pushing amount of 10, and the centering in the left-right direction can be performed by the guide drive mechanism 120 provided in the middle of the carry-in path. The guide drive mechanism 120 has carry-in guides 121 and 122 that contact the left and right ends of the tray T from outside to position the tray T in the left-right direction. The movement of the carry-in guides 121 and 122 is controlled so that the tray T is centered in the left-right direction based on the width of the tray T obtained from the image processing result of the imaging by the CCD camera or the detection result of the sensor.

(F) In the above embodiment, the side surfaces of the tray T are held by the tray holding members 21 to 24 to mainly prevent the tray T from being displaced in a planar manner. Or, in addition to this, Tray T
May be sucked and held. Specifically, it is conceivable that a hole is provided in a central portion of the fixed support plate 20a of the tray mounting and holding mechanism 2 and a suction device is connected to the hole via a pipe.

(G) In the above embodiment, the coil springs 27d and 27e are employed as means for urging the tray holding members 21 to 24 holding the tray T inward, but this is changed to a torque motor or the like. It is also possible to adjust the biasing force. If the coil springs 27d and 27e are changed to urging means such as a torque motor or an air cylinder capable of adjusting the urging force, the control unit 10 holds the tray T according to parameters such as the hardness of the tray T and the material of the tray T. The holding power can be changed. For example, in the case of a soft tray T, the urging force (holding force) is reduced, and in the case of a hard tray T, the urging force (holding force) is reduced.
Can be controlled so as to strengthen. This allows
It is possible to reliably prevent the tray T from being displaced and suppress a problem that the tray T is deformed and a sealing failure occurs. Further, the urging force of the urging means, that is, the holding force of the tray can be adjusted according to the characteristics of the stretch film Fm such as the thickness and the material.

Further, if means (urging force detecting means) for confirming the holding force such as a pressure sensor is provided at the contact portions 21a to 24a of the tray holding members 21 to 24, the urging force of the urging means such as an air cylinder is provided. Can be verified. If the control unit 10 controls the urging force of the urging means based on the detection result of the urging force detecting means, it is possible to eliminate problems such as defective sealing due to deformation of the tray T.

(H) Although the packaging device 1 of the above embodiment does not have a weighing function, when the tray T is placed on the tray mounting and holding mechanism 2 being pulled out, the packaged object including the tray T is included. , And then perform a series of packaging processes. In this case, in order to shift to the packaging process, the control unit 10 needs to send a packaging start request, information on the size of the packaged object (tray size and height), and information on the material of the stretch film and the material of the tray. I need to tell. Among these, the following is mentioned as a method of inputting a packaging start request to the control unit 10. (A) The tray mounting / holding mechanism 2 is provided with fins and the tray T
Is weighed, and the packaging operation is started by the weighing stability signal. (B) The tray T placed on the tray placing and holding mechanism 2 is detected by a sensor, a proximity switch, or the like, and the packaging operation is started by the detection signal. (C) The tray T placed on the tray placing and holding mechanism 2 is recognized by a CCD camera or the like, and the packaging operation is started by the recognition completion signal. At the time of completion of the recognition, the tray size is written in the data area in the RAM 13 of the control unit 10. (D) The packaging operation is started by the operation of the operator pressing the packaging start button.

In the above methods (a) and (b),
Tray master file 14 preset in control unit 10
By inputting a packaging condition value such as a tray size such as calling a, the packaging of the tray T to which the packaging start signal has been input can be started. In the method (c), based on the recognized tray size, a tray master file 14a that matches a previously input tray size can be called and packaging conditions can be set.

In the method (d), similarly to (a) and (b), an operation of separately calling the tray master file 14a is required. That is, in the case of the method (c), the tray T
The packaging can be started only by the operation of placing the tray on the tray placing and holding mechanism 2. According to the methods (a) and (b), the packaging can be started by the operation of calling the tray master file 14a and the operation of placing the tray T. And
In the case of the method (d), the operation can be started by the operation of calling the tray master file 14a, the operation of placing the tray T, and the operation of inputting a packaging start signal.

Which of the above methods (a) to (d) should be selected may be determined in consideration of productivity, cost, and the like.

[0092]

In the top seal type packaging apparatus according to the present invention, a tray holding member is provided to hold the tray so that the position of the tray is not shifted by the contact of the heat when the stretch film is welded to the tray. I have. As a result, the position of the tray with respect to the heating element can be maintained at an optimum position, and the heating element comes into contact with the peripheral portion of the opening of the tray as designed, thereby reducing the occurrence of sealing failure due to displacement of the tray.

In the top-sealing type packaging apparatus / top-sealing type packaging method according to another aspect of the present invention, when the stretch film is welded to the tray, the tray is positioned at the optimum position with respect to the heating element. Adjusting the flat position of the tray before pressing. Thereby, the position of the tray with respect to the heating element is adjusted to the optimum position, and the occurrence of sealing failure due to the position shift of the tray is reduced.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a packaging device according to an embodiment of the present invention.

FIG. 2 is a longitudinal sectional view of the packaging device.

FIG. 3 is a diagram showing the operation of the packaging device.

FIG. 4 is a diagram showing the operation of the packaging device.

FIG. 5 is a plan view of a roller.

FIG. 6 is a diagram illustrating a plane trajectory obtained by turning a roller.

FIG. 7 is an enlarged view of the vicinity of the flange of the tray at the time of contact with a roller.

FIG. 8 is an enlarged view of the vicinity of the flange of the tray at the time of film thermal welding.

FIG. 9 is a control block diagram of the packaging device.

FIG. 10 is an arrangement diagram of members on the front and side surfaces when the tray mounting / holding mechanism is pulled out.

FIG. 11 is a front and side view of the arrangement of members when the tray mounting / holding mechanism is pushed.

FIG. 12 is a plan view of member arrangement when the tray mounting and holding mechanism is pulled out.

FIG. 13 is a plan view of the member arrangement when the tray mounting / holding mechanism is pushed.

FIG. 14 is a plan view illustrating the operation of the tray holding member.

FIG. 15 is a plan view of a member arrangement when a link mechanism or the like of the tray mounting / holding mechanism is pulled out.

FIG. 16 is a plan view of member arrangement when a link mechanism or the like of the tray mounting / holding mechanism is pushed.

FIG. 17 is an enlarged plan view of the member arrangement when the link mechanism and the like of the tray mounting and holding mechanism are pulled out and pushed in.

FIG. 18 is a diagram showing an arrangement of a belt conveyor in a carry-in path in another embodiment (E).

FIG. 19 is a diagram showing a configuration of a guide driving mechanism in a carry-in path according to another embodiment (E).

[Explanation of symbols]

REFERENCE SIGNS LIST 1 packaging device 2 tray mounting and holding mechanism (tray mounting and holding mechanism; position adjusting mechanism) 3 roller (heat body) 5 film transport mechanism (film supply mechanism) 6 lift mechanism 10 control unit 21 to 24 first to fourth trays Holding members 21a to 24a Contact parts 27a, 27b Link mechanism 27c Center axis 27d, 27e Coil spring T Tray f Flange (part around opening of tray) Fm Stretch film

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3E049 AA01 AB03 BA04 CA10 DB02 EA02 EB03 EC02 FA07 3E094 AA04 CA10 CA12 CA15 CA17 DA02 FA13 GA04 GA11 HA03 HA08 HA10 HA11

Claims (11)

[Claims] 1. A top-seal type in which an opening is covered with a stretch film in a tray having an upper portion opened while a packaged object is accommodated in the tray, and the stretch film is welded to a portion around the opening of the tray. A packaging device, comprising: a film supply mechanism that supplies the stretch film above the tray; a lift mechanism that raises the tray and presses the stretch film; and around an opening of the tray with which the stretch film is in contact. A heat body that contacts the portion and welds the stretch film to a portion around the opening of the tray; and a tray holding member that holds the tray when the stretch film is welded to the portion around the opening of the tray. Top seal type packaging equipment. 2. The top seal type packaging device according to claim 1, wherein the tray holding member further prevents the tray from being displaced when the tray is raised and pressed against the stretch film. 3. The top-sealing type packaging apparatus according to claim 1, wherein the tray holding member contacts a side surface of the tray to prevent the tray from being displaced in a planar manner. 4. A tray mounting / holding mechanism which mounts the tray and is transferred to the lift mechanism together with the tray, wherein the tray holding member is included in the tray mounting / holding mechanism, The top seal type packaging device according to any one of claims 1 to 3, wherein the lift mechanism raises the tray by lifting the tray mounting and holding mechanism. 5. The top seal according to claim 1, wherein the tray mounting / holding mechanism adjusts the planar position of the tray by urging the tray holding member toward the tray. Type packaging equipment. 6. A position detecting means for detecting a position state of the tray when the tray is transferred to the lift mechanism, and a position of the tray by the tray holding member based on a detection result of the position detecting means. A control unit for correcting the displacement,
The top seal type packaging device according to any one of claims 1 to 3, further comprising: 7. The apparatus according to claim 1, further comprising: urging means for urging said tray holding member toward said tray; and a control unit for controlling an urging force of said urging means. The top seal type packaging device according to the above. 8. The apparatus according to claim 1, further comprising: an urging force detecting unit configured to detect an urging force of the urging unit, wherein the control unit controls the urging force of the urging unit based on a detection result of the urging force detecting unit. A top seal type packaging device according to claim 7. 9. The top-seal type packaging apparatus according to claim 7, wherein said control unit controls the urging force of said urging means corresponding to at least one of the characteristics of said tray and the characteristics of said stretch film. 10. A top seal type for covering a tray having an open top with a stretch film in a state in which an article to be packaged is accommodated in the tray, and welding the stretch film around an opening of the tray. A packaging apparatus, comprising: a film supply mechanism that supplies the stretch film above the tray; a lift mechanism that raises the tray and presses the stretch film; and around an opening of the tray with which the stretch film is in contact. A heat body that contacts the portion and welds the stretch film to a portion around the opening of the tray; and a position adjustment mechanism that adjusts a planar position of the tray before the tray is pressed against the stretch film.
Top-sealing type packaging device equipped with 11. A tray having an opening at an upper portion, the opening is covered with a stretch film in a state in which an object to be packaged is accommodated in the tray, and a heat is applied to a peripheral portion of the opening of the tray to apply the stretch film. A top seal type packaging method for welding, wherein: a film supply step of supplying the stretch film above the tray; a position adjustment step of adjusting a planar position of the tray; and raising the tray and pressing the tray against the stretch film A top seal type comprising: a lifting step to be applied; and a welding step of bringing the heat body into contact with an opening peripheral portion of the tray with which the stretch film is in contact and welding the stretch film to the opening peripheral portion of the tray. Packaging method.