JP2003231501A - Top sealing package apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a top sealing package apparatus, which carries out heat sealing in a proper condition even if temperature changes widely in an install position of the apparatus, so that occurrence of sealing failure is lessened. <P>SOLUTION: According to the top sealing package apparatus 1, the top opening of a tray T is covered with a stretch film Fm, which is welded to the flange of the tray T. The package apparatus 1 comprises rollers 3, a roller slewing mechanism 8, a temperature sensor 41, and a controller. The rollers 3 comes from above the stretch film Fm into contact with the flange of the tray T to heat it. The roller slewing mechanism 8 moves the rollers 3 along the flange of the tray T. The sensor 41 indirectly measures the temperature of the stretch film Fm. The controller controls the heaters of the rollers 3 and the roller slewing mechanism 8 on the basis of a measurement result given by the temperature sensor 41. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a packaging device, in particular
The present invention relates to a top-seal type packaging device in which an object to be packaged is accommodated in a tray having an open upper part, and the opening is covered with a film to weld the film to the tray.

[0002]

2. Description of the Related Art Conventionally, an overlap method has been widely 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 the tray is wrapped with the objects to be packaged and then the entire tray is wrapped with a film.

However, in the case of the overlap type, since the tray and the whole article to be packaged must be wrapped and the film must be overlapped for sealing,
A film that is several times larger than the planar size of the tray is required. Also, stack the films on the bottom of the tray,
In many cases, the bottom of the tray is pressed against the hot plate for sealing, resulting in poor sealing performance.

On the other hand, a method of bringing the film only into the opening of the tray whose upper surface is open and welding the film around the opening of the tray and the film (hereinafter referred to as the top seal method) is overlapped. It is used in some parts instead of the method. In this top seal method, the amount of film used can be halved compared to the case where the overlap method is adopted.

Regarding the top seal system, the applicant of the present application has previously developed the technique disclosed in Japanese Patent Laid-Open No. 2001-328608. There, the tray is pushed up from below against the held film to generate tension in the film, and in that state, the contact overlapping portion between the flange of the tray and the film is heated by a heat roller or the like, and the film is welded to the flange. At the same time, the film is melted off on the outside of the welded portion. As a result, trays of various sizes and shapes can be accommodated regardless of the tray size and tray shape.

[0006]

In the top-seal type packaging device disclosed in the above publication, the films are heat-welded to the flanges of the trays, so that the films are heat-welded to each other. Compared with the above, selection of the material of the tray and film becomes more important.
Further, it is also necessary to properly manage the heat input amount by a heat roller or the like, and in the apparatus described in the above publication, the moving speed of the roller and the heating are controlled according to the characteristics of the tray and the film.

However, the ease with which the film is welded to the tray changes between when the ambient temperature is high and the film or the like is preheated, and when the ambient temperature is low and the film or the like is cold. . The space in which the packaging device is installed is not always air-conditioned, and it is desirable to be able to cope with temperature changes in order to prevent defective sealing. An object of the present invention is to provide a top-seal type packaging device in which heat sealing (welding) is performed under appropriate conditions even when a temperature change is large in a place where the device is installed and sealing defects are small.

[0008]

According to a first aspect of the present invention, there is provided a packaging apparatus, in which a tray having an open upper portion is covered with a film in a state where an object to be packaged is accommodated in the tray, and a portion around the opening of the tray is provided. It is a top seal type packaging device that welds a film. This device includes a heating unit, a moving unit, a temperature sensor, and a control unit. The heating means abuts on a peripheral portion of the opening of the tray covered with the film and heats the peripheral portion of the opening of the tray. The moving means moves the heating means along the peripheral portion of the opening of the tray. The temperature sensor directly or indirectly measures the temperature of the film. The control unit, based on the measurement result by the temperature sensor,
At least one of the heating means and the moving means is controlled.

In the packaging apparatus of the first aspect, the heating means is brought into contact with the peripheral portion of the opening of the tray covered with the film, whereby the film and the peripheral portion of the opening of the tray are heat-welded. Then, by moving the heating means along the peripheral portion of the opening of the tray by the moving means, the heating means is brought into contact with each part of the peripheral portion of the opening of the tray, and the film is attached to the entire periphery of the peripheral portion of the opening of the tray. It can be welded.

Then, here, at least one of the heating means and the moving means is controlled based on the measurement result by the temperature sensor. Even if the same film is used, if the temperature of the film itself is different, the amount of heat required for welding will be different, but here because the heating means and moving means are controlled in a form that matches the temperature of the film, The amount of heat input to the portion of the tray that overlaps the peripheral portion of the opening can be made appropriate, and defective welding due to excessive or insufficient heating can be avoided.

The temperature sensor may directly measure the temperature of the film or may measure the air temperature. Even when the temperature sensor measures the air temperature, the control unit can indirectly grasp the degree of cooling or warming of the film from the temperature. When a temperature sensor for measuring the air temperature is used, the temperature sensor may be arranged near the film, or may be arranged inside or outside the device connected to the space around the film. However, when the space in which the film is located is a space that is closed to some extent, it is necessary to dispose the temperature sensor in the space.

A top seal type packaging device according to a second aspect is the device according to the first aspect, further comprising a film roll holding portion. The film roll holding unit holds the film roll wound with the film to be fed between the tray and the heating means. Further, the temperature sensor measures the air temperature around the film roll held by the film roll holding unit.

In this case, the temperature of the film fed between the tray and the heating means can be indirectly measured by measuring the air temperature around the film roll with a temperature sensor. Further, the temperature of the film can be more accurately estimated as compared with the case where the temperature sensor is installed at a place distant from the film roll. A top seal type packaging device according to a third aspect is the device according to the second aspect, further including a blower. The blower creates an air flow around the film roll. The control unit further controls the blower based on the measurement result of the temperature sensor.

Here, based on the measurement result of the temperature sensor, the blower can be controlled to generate an air flow around the film roll. As a result, for example, when the temperature of the film roll is high and there is a possibility that holes will be opened in the film covering the tray during welding unless the film temperature is lowered, the air blower creates an air flow near the film roll. The temperature rise of the roll can be suppressed. Further, in winter, when it is not desired to cool the film roll, it is possible to stop the operation of the blower to prevent heat from being taken from the film roll.

A top seal type packaging device according to a fourth aspect is the device according to the third aspect, wherein the blower is provided near the film roll held by the film roll holding portion. Here, since the blower is provided near the film roll, the air flow can be effectively generated around the film roll.

A top seal type packaging device according to a fifth aspect is the device according to the third aspect, wherein the blower is provided in the space above the heating means or in the vicinity thereof. Here, since the blower is provided near the heating means, the air heated by the heating means can be treated according to the situation. For example, in summer, when it is desired to prevent hot air from flowing through the film roll, a blower can generate an air flow in a direction in which the air above the heating means moves away from the film roll. Further, when it is desired to warm the film roll in winter, it is possible to blow the air warmed by the heat of the heating means to the film roll by means of a blower.

When heat is accumulated above the heating means,
There is a problem that the sensors and machines located there are adversely affected or the casing of the device becomes too hot. However, in the device of claim 5, the blower can eliminate the accumulation of heat, and these problems are It can be suppressed.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION <Outline of Apparatus> FIGS. 1 and 2 show a top-seal type packaging apparatus which is an embodiment of the present invention. The packaging device 1 shown here covers the upper opening o of a tray T containing fresh foods such as meat and fish and processed foods such as side dishes with a stretch film Fm (see FIGS. 3 and 4), and FIGS. As shown in FIG. 5, the device is a device that heat-welds and seals a stretch film Fm with a flange (portion around the opening) f located around the opening o of the tray T.

<Device Configuration> This packaging device 1 includes a casing 1a, a tray placing and holding mechanism 2 for holding a tray T,
The four rollers 3 located above the tray mounting / holding mechanism 2, the film transport mechanism 5 for supplying the stretch film Fm between the tray mounting / holding mechanism 2 and the rollers 3, and the tray mounting / holding mechanism 2 are moved up and down. A lift mechanism 6, a roller vertical movement mechanism 7 for mainly moving the roller 3 up and down, a roller swivel mechanism 8 having two swivel shafts for swiveling the roller 3 around each swivel shaft 81a, 81b, and a tray placement / holding mechanism 2. A stretch mechanism 9 for stretching the stretch film Fm with the roller 3, and a control unit 1 for controlling each mechanism.
0 (see FIG. 9) and the like.

<Detailed Configuration of Each Part> [Casing] The casing 1a includes each mechanism 2, 3, 5,
It covers 6, 7, 8 and 9 to prevent an operator from inadvertently touching the driving part or the heating part with his / her hand. At the top of the casing 1a, as shown in FIG. 12, an air intake port 1b is provided on the front side of one side surface (front side of FIG. 12).
The air discharge port 1c is provided on the side of the back surface close to the other side surface. The air discharge port 1c is located diagonally above the back side end of the film roll R set in the film setting unit 51, which will be described later, and the axial fan 42 is mounted therein. The axial fan 42 is installed from the inside of the casing 1a to the casing 1a.
This is a blower capable of discharging air to the outside, and the built-in motor 42a (see FIG. 9) is ON / OFF controlled by the control unit 10 described later. As the axial fan 42 operates, particularly in the upper part of the space inside the casing 1a, as shown by the double-lined arrow in FIG. 12, the air flows from the air intake port 1b into the casing 1a and the air discharge port. A flow of air discharged from 1c to the outside of the casing 1a is formed.

[Tray Placement / Holding Mechanism] The tray placement / holding mechanism 2 holds and holds the tray T on its upper surface, and is lifted and lowered by the lift mechanism 6. Further, the tray placing / holding mechanism 2 can be pulled out from the position shown by the solid line in FIG. 2 to the position shown by the chain double-dashed 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 / holding mechanism 2 may be performed manually by an operator, or automatically transferred from a separately prepared tray T transporting device. You may do it. [Roller] The roller 3 is a cylindrical member, and is rotatably supported by a roller supporting portion 71 of a roller vertical movement 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 if the surface of the flange f of the tray T has minute irregularities, the stretch film Fm and the flange f are pressure bonded together. It has been secured.

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

Further, these rollers 3 are shown in FIGS.
As shown in FIG. 5, the roller support portion 71 is supported in a state of being inclined with respect to the upper surface of the tray T which is parallel to the horizontal plane when viewed from the side. This inclination is set so that the end of the roller 3 on the side of the turning shafts 81a and 81b is located higher than the other end. In addition, inside the roller 3, the roller 3
A heater 31 (see FIG. 9) for heating is disposed.
The heater 31 has an appropriate specification selected according to the material of the tray T or the stretch film Fm to be sealed in consideration of the necessity of inputting energy capable of recovering the amount of heat taken by the seal in a short time.

[Film Transport Mechanism] Film transport mechanism 5
Is a mechanism for feeding out the stretch film Fm between the tray placing / holding mechanism 2 and the roller 3 which are in a lowered state, and for winding up the stretch film Fm which is partially cut out by fusing due to sealing. As shown in FIG. 1, the film transport mechanism 5 includes a film setting unit 51.
And a film winding section 53 and a film transport section 52.

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

Further, as shown in FIGS. 1 and 12, a temperature sensor 41 is provided in the space located on the diagonally rear side of the film roll R set in the film setting section 51. The temperature sensor 41 is a sensor that measures the air temperature, and is used to indirectly estimate the temperature of the film roll R by measuring the air temperature around the film roll R.

The film winding section 53 is provided for winding the remaining stretch film Fm, a part of which has been extracted by the packaging (top seal) of the tray T, and has a winding shaft 53a. This winding shaft 5
3a is rotated by a belt 53b that is wound around a motor 52c described later. The film transport unit 52 uses the feeding roller 52a and the feeding roller 52a to rotate the belt 5
It is provided with a motor 52c that is rotationally driven via 2b and a film support roller 52d. The stretch film Fm pulled out from the film roll R is rotated by the feeding roller 52a to drive the stretch film Fm.
Is sent to the side. Further, as the motor 52c rotates, the take-up roller 52a and the take-up shaft 53a also rotate, so that the stretch film Fm is taken up from the film roll R and taken up by the take-up shaft 53a. The rotation speed of the winding shaft 53a is set to be higher than the rotation speed of the payout roller 52a. Therefore, the stretch film Fm is in a state in which tension along the transport direction is applied. As a result, slack-free transportation is performed.

The feeding roller 52a has gripping property with respect to the stretch film Fm, and can suppress the slip and feed the stretch film Fm by a predetermined amount. Specifically, a one-way clutch (not shown) is provided to apply a mirror finish to the surface of the feeding roller 52a and prevent the feeding roller 52a from rotating in the reverse direction. As shown in FIG. 1, the feeding roller 52a is provided with a lead supporting member 5a.
It is arranged symmetrically with the support roller 51b with the la 1a interposed therebetween. The distance between the feeding roller 52a and the support roller 51b is set to be smaller than the diameter of the core material of the film roll R, and the film roll R is prevented from slipping off between these rollers 52a and 51b. There is.

The film supporting roller 52d is arranged in the vicinity of the film winding portion 53, and is set so that the height of the upper surface thereof coincides with the lower surface of the feeding roller 52a (see FIG. 1). Therefore, the portion of the stretched film Fm being conveyed between the feeding roller 52a and the film supporting roller 52d is kept horizontal.

[Stretch Mechanism] The stretch mechanism 9 is
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 for gripping both side ends of a horizontal portion between 2a and the film support roller 52d and stretching the stretch film Fm in the width direction (the left and right direction in FIG. 2). The stretch mechanism 9 includes a pair of film grips 91a and 91b extending in the film transport direction, and a stretch drive unit 93 (see FIG. 9) that moves the film grips 91a and 91b in a direction orthogonal to the film transport direction (left and right directions in FIG. 2). have.

The film grip portions 91a and 91b are structured to grip the stretch film Fm from both upper and lower sides, and are turned on / off by using solenoids 92a and 92b (see FIG. 9). Further, rubber (or resin) pads p1 to p8 having a large friction coefficient are attached to a portion in contact with the stretch film Fm from above to prevent slipping between the film grip portions 91a and 91b and the stretch film Fm. is doing. That is, the film grip portions 91a and 91b have a structure that grips the stretch film Fm by sandwiching it between the pads p1 to p8 and the lower member 94.

The stretch drive section 93 includes a motor 93a.
(See FIG. 9), a guide rail, a sprocket, a chain, etc., and moves the film gripping portions 91a, 91b in the left-right direction in FIG. 2 in accordance with a command from the control unit 10. [Lift Mechanism] The lift mechanism 6 is a mechanism for pushing up the tray placing / holding mechanism 2 holding the tray T with respect to the stretch film Fm as shown in FIG. The lift mechanism 6 includes a drive motor 61, a large gear 62, and a link member 6.
3, lever 64 and lever 6 which rotate around the fulcrum 64a
It is composed of a disk member 65 and the like which is rotatably mounted on the tip of the disk 4.

When the drive motor 61 operates, the large gear 62 rotates via the gear fixed to the motor shaft. Then, the lever 64 is supported by the fulcrum 64a via the link member 63.
Rotate around. As a result, the tray placing / holding mechanism 2 whose lower surface is supported by the disc member 65 moves up and down (see FIGS. 2 and 3). The tray placing and holding mechanism 2
Is guided by a vertical guide rail 69,
The lift mechanism 6 operates to move in the vertical direction.

[Roller Vertical Movement Mechanism] The roller vertical movement mechanism 7 is a mechanism for changing the height position of the roller 3, and as shown in FIG. 1, a roller support portion 71 for pivotally supporting the roller 3, The link mechanism 72 includes a pressing plate 73, a lever mechanism 74 that applies a force to the pressing plate 73 from above, and a motor 75 that operates the lever mechanism 74.

The roller support portion 71 pivotally supports the roller 3 so that the roller 3 is in the inclined state shown in FIGS. 1 and 2 in a side view. 1 in the roller 3 shown in FIGS. 1 and 2.
The dotted chain line is the rotation axis of the roller 3. Link mechanism 72
Has one end pin-supporting the roller support portion 71 and the other end pushed down by the pressing plate 73. When the other end of the link mechanism 72 is pushed down by the pressing plate 73, one end is raised as shown in FIGS. 1 and 2, and the roller support portion 71 and the roller 3 are also raised. Become. On the other hand, the pressing plate 73 is the link mechanism 72.
When the force is not applied to the roller supporting portion 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 resting on the rolling element that is axially supported by the other end of the link mechanism 72. [Roller Revolving Mechanism] The roller revolving mechanism 8 is a mechanism that revolves the roller 3 and the roller support portion 71 and the link mechanism 72 that support the roller 3 at a predetermined angle during the seal packaging. The roller turning mechanism 8 mainly includes a first turning shaft 81a,
It is composed of a second turning shaft 81b and a motor 82 that rotates both turning shafts 81a and 81b.

The lower end of the first turning shaft 81a is fixed to a base member 79 that supports the two link mechanisms 72, and the upper end thereof meshes 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 (a member different from the base member 79 to which the first turning shaft 81a is fixed) that supports another two link mechanisms 72. Further, the upper end of the second turning shaft 81b meshes with the main gear 83 via a gear (see FIG. 5).

When the motor 82 rotates the turning shafts 81a, 81b by a predetermined angle under the control of the control unit 10, each roller 3 turns by the predetermined angle about the first turning shaft 81a or the second turning shaft 81b as a rotation center. (See FIG. 6).
In FIG. 6, for the sake of easy understanding, the roller 3 connected to the first swivel shaft 81a is replaced with the rollers 3a and 3b.
The rollers 3 connected to the second turning shaft 81b are indicated as rollers 3c and 3d. In addition, in FIG.
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 the CPU 11 as the main body of the control unit,
A ROM 12 and a RAM 13 are mounted as a main storage unit controlled by the CPU 11. Furthermore, the control unit 10
A display control circuit 15a for controlling the data display on the display 15 for displaying to the operator, a keyboard circuit 16a for taking in key input data from the keyboard 16 which receives an input from the operator, and the like are provided.

The control unit 10 also 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, and tray shape for each tray number. On the other hand, in the RAM 13, a data area for storing tray information called from the tray master file 14a is formed.

Then, the CPU 11, the ROM 12 and the RAM
The HDD 13, the HDD 14, and the circuits 15a and 16a are connected to each other via bus lines such as an address bus and a data bus. This control unit 10, as shown in FIG.
It is connected to drive means such as a motor of each mechanism, the motor 42a of the axial fan 42, and the heater 31, and controls these.

<Operation Control of Packaging Device> [Overall Control] When the tray T containing a package such as food is placed on the tray placing / holding mechanism 2 which is pulled out to the position shown by the chain double-dashed line in FIG. The tray placing and holding mechanism 2 horizontally moves below the roller 3 by hand or by driving means (not shown).

The tray placing and holding mechanism 2 that has moved below the roller 3 positions the tray T by pushing the side surface of the tray T by a plurality of holding members, and holds the tray T so as to prevent the tray T from being displaced. To do. The control unit 10 calculates the feed amount of the stretch film Fm by the film transport mechanism 5 according to the tray. More specifically, the control unit 10 calls the tray size, the tray material, and the like stored in the tray master file 14a from the tray number input from the keyboard 16, and calculates the feed amount of the stretch film Fm.

When the stretch film Fm is fed from the film transport mechanism 5, the control unit 10 operates the stretch mechanism 9 to stretch the stretch film Fm in the width direction (left and right direction in FIG. 2). As a result, the stretch film Fm is tensioned in the width direction and is in a wrinkle-free state. The operation of stretching the stretch film Fm by the stretch mechanism 9 will be described in detail later.

Next, the control section 10 operates the lift mechanism 6 to lift the tray placing and holding mechanism 2 holding the tray T. Accordingly, the tray T pushes up the stretch film Fm and stops (see FIG. 3). The amount of rise of the tray placing / holding mechanism 2 at this time is determined based on the height dimension of the tray T. The control unit 10 determines the amount of rise of the tray placing and holding mechanism 2 so that the upper surface of the tray T has a substantially constant height position.

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

Next, the control unit 10 controls the motor 82 to rotate the turning shafts 81a and 81b by a predetermined angle. This predetermined angle is set to 110 ° here (see FIG. 6) so that the entire flange f of the tray T is sealed by any of the rollers 3a to 3d. Swivel axis 81a,
When the roller 3 rolls on the tray T from above the stretch film Fm by turning around 81b, the roller 3 heat-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 rollers 3 move 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 pressure-bonded to the flange f of the tray T. Then, the roller 3 obliquely hits the contact portion between the stretch film Fm and the flange f from above to apply heat and force. By these heat and power, the stretch film F
m and the flange f are heat-welded. Further, at this time, heat and force are concentrated 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 abuts), so that the stretch film Fm at the edge portion of the tray T. Are 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 heat-welded and the stretch film Fm is melted and cut off outside the joint portion by the heat-welding.

When 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. Then, the tray T sealed and packed is taken out from the tray placing / holding mechanism 2 that has been pulled out,
Move on to the next cycle. When moving to the next cycle, the stretch film Fm, which is partially cut by heat fusion by the seal packaging of the tray T, is wound around the winding shaft 53a. At this time, since the film supporting roller 52d and the feeding roller 52a are rotated by the rotation of the motor 52c, the stretching of the stretch film Fm for the next cycle (the feeding of the stretch film Fm below the roller 3) is performed simultaneously with the winding. Be seen.

The width of the stretch film Fm is set to be wider than the width of the tray T at least when stretched by the stretching mechanism 9, and the tray T is sealed and packaged (the stretch film Fm is melted and removed). Therefore, the continuity of the stretch film Fm is not interrupted, and the problem that the film winding unit 53 cannot wind the film does not occur.

[Control Based on Measurement Result of Temperature Sensor] The measurement result of the temperature sensor 41 is the ambient temperature of the film roll R. If this temperature is high, the stretch film Fm of the film roll R is warm, and if it is low, the film is The stretch film Fm of the roll R is cold. When the stretch film Fm is warm, it is likely to be heat-welded, and when the stretch film Fm is cold, it is difficult to be heat-welded.
Controls the heater 31 of the roller 3 and the motor 82 of the roller turning mechanism 8 based on the measurement value of the temperature sensor 41.

Specifically, the control unit 10 controls the temperature sensor 4
When it is determined from the measurement result of No. 1 that the stretch film Fm is warm, the heating of the roller 3 is weakened or the turning speed of the roller 3 is increased according to the degree of warming. On the contrary, when it is determined that the stretch film Fm is cold, the heating of the roller 3 is strengthened or the turning speed of the roller 3 is slowed according to the degree of the cold. As a result, due to insufficient heat input, the stretch film F
This prevents problems such as insufficient thermal welding between m and the flange f, and perforation of the stretch film Fm covering the flange f due to excessive heat input.

Based on the measurement result of the temperature sensor 41, the axial fan 42 provided near the film roll R is ON / OFF controlled. The control unit 10 compares the measured temperature value of the temperature sensor 41 with a threshold value having a predetermined range, operates the axial fan 42 when the measured value exceeds the threshold value, and the measured value is a threshold value. When the value falls below the value, the axial fan 42 is stopped. When the axial fan 42 is operating, an air flow shown by a double line in FIG. 12 is generated in the upper part of the casing 1a, and the film roll R
It is possible to suppress an increase in the ambient temperature due to the heat of the heater 31. On the other hand, when the axial fan 42 is stopped, the heat of the heater 31 raises the temperature of the air in the casing 1a and warms the film roll R. That is, the ON / OFF control of the axial fan 42 described above allows the change in the ambient temperature of the film roll R to be suppressed to be relatively small.

[Control of Stretching Mechanism] The control unit 10
The stretch mechanism 9 is not operated during the transport of the stretch film Fm by the film transport mechanism 5, and is operated when the stretch film Fm is welded to the tray T. When welding the stretch film Fm to the tray T, the control unit 10 operates the stretch mechanism 9 in four stages. The control of the stretch mechanism 9 will be described with reference to FIGS. 10 and 11.

First, as a first step, as shown in FIG. 10A, both side portions of the stretch film Fm are gripped by the film gripping portions 91a and 91b at the home position (HP), and FIG. As shown in, both the film grip portions 91a and 91b are moved to the outside to stretch the stretch film Fm. That is, before the tray T is pushed up to the stretch film Fm by the lift mechanism 6,
The stretch mechanism 9 is operated to stretch the stretch film Fm in advance. Stretch film Fm at this time
The stretching operation of is called a pre-stretching operation, and the stretching amount of the stretch film Fm is called a pre-stretching amount.

Next, as the second step, when the tray T is lifted by the lift mechanism 6, the stretch mechanism 9 is operated immediately after the tray T is pressed against the stretch film Fm to loosen the stretch of the stretch film Fm.
That is, between the time when the tray T starts contacting the stretch film Fm as shown in FIG. 10C and the time when the tray T fully rises as shown in FIG. To loosen the tension of the stretch film Fm. However, FIG. 11 (d)
Even when the tray T shown in (3) is fully raised, the stretch film Fm is in a state of being tensioned to some extent.

Next, as a third step, after the stretch film Fm is welded to the tray T by the roller 3 as shown in FIG.
1b is moved to the outside to stretch the stretch film Fm. This stretching operation is performed by the stretch film F
It may also play a role of complementing the melting of m. And
As the fourth stage, stretch film Fm on tray T
After the welding and the cutting of the stretch film Fm are completed and the roller 3 is pulled up and the tray T is lowered, both the film grip portions 91a and 91b of the stretch mechanism 9 are returned to the home positions.

<Characteristics of the packaging device of this embodiment> (1) Here, when the ambient temperature of the film roll R is high, an air flow is generated around the film roll R by the ON / OFF control of the axial flow fan 42. When the ambient temperature of the film roll R is low, the air flow around the film roll R is stopped. Therefore, even when the temperature change in the installation environment of the packaging device 1 is large, the temperature change of the stretch film Fm of the film roll R can be suppressed to be relatively small. As a result, defects in heat welding between the stretch film Fm and the flange f are reduced. Further, even in the winter, the stretch film Fm indirectly receives the heat of the heater 31 and is heated, so that the stretch film Fm is stretched to a substantially desired level in the pre-stretching operation.

(2) Here, the heater 31 for heating the roller 3 and the motor 82 of the roller turning mechanism 8 for turning the roller 3 are controlled based on the measurement result of the temperature sensor 41. Specifically, the higher the ambient temperature of the film roll R, the smaller the heating of the roller 3 and the faster the rotation speed of the roller 3, and the lower the ambient temperature of the film roll R, the greater the heating of the roller 3 and the higher the rotation speed of the roller 3. I'm late. When the turning speed of the roller 3 is slowed, the time during which the roller 3 is in contact with the overlapping portion of the stretch film Fm and the flange f becomes longer, and the amount of heat input by the roller 3 increases.

As a result, problems such as insufficient heat sealing (heat welding) due to the low temperature of the stretch film Fm and perforation of the stretch film Fm due to the high temperature of the stretch film Fm are reduced. <Modification> (A) In the above embodiment, the axial fan 42 is provided in the vicinity of the film roll R as shown in FIG. 12, but instead of or in addition to this, the axial fan 42 is a heater. It is also effective to provide in the upper space of the roller 3 having 31 or in the vicinity thereof.

The air above the roller 3 is the film roll R.
When an axial fan is installed in such a direction that it can flow to the side, when you want to warm the film roll R in winter,
The air above the roller 3 warmed by the heat of the heater 31 can be sent to the film roll R by an axial fan. On the contrary, when an axial fan is installed so that the air above the roller 3 flows in the direction away from the film roll R, when it is desired to prevent hot air from flowing to the film roll R in the summertime, It is possible to prevent the film roll R from becoming hot by operating the flow fan.

If an actuator is provided so that the air flow can be switched between two directions by the axial fan above the roller 3, it is possible to generate an air flow suitable for the respective conditions of winter and summer. become.
Further, if the axial fan is provided above the roller 3, it is possible to prevent heat from being trapped in the space above the roller 3 in the casing 1a, and to prevent various sensors and machines from being adversely affected by heat.

(B) In the above embodiment, the temperature sensor 41 is used.
A heater 31 for heating the roller 3 based on the measurement result of
The motor 82 of the roller turning mechanism 8 and the axial fan 42
Although the motor 42a is controlled, the motor 93a of the stretching mechanism 9 may be controlled in addition to this. By performing such control, it becomes possible to perform the pre-stretching operation corresponding to the characteristic change of the stretch film F due to the temperature change.

(C) In the above embodiment, the temperature sensor 41 for measuring the air temperature around the film roll R is used to estimate the temperature of the stretch film Fm. However, a non-contact type temperature sensor or the like is used. It is also possible to directly detect the temperature of the stretch film Fm. In this case, although the cost is increased, it is possible to more accurately control the roller 3 and the axial fan 42 based on the temperature of the stretch film Fm.

(D) In the above embodiment, the temperature sensor 41 is used.
The axial fan 42 is controlled to be stopped when the ambient temperature of the film roll R being measured by means of the above. In addition to this, a shutter is provided at the air intake port 1b of the casing 1a, and It is also effective to control opening / closing according to ON / OFF of the motor 42a of the axial fan 42. Axial fan 42 when it is cold in winter
If the air intake 1b is closed with the shutter closed, the temperature inside the casing 1a can be efficiently increased by the heat of the heater 31 and the film roll R can be expected to warm.

[0067]

According to the present invention, since at least one of the heating means and the moving means is controlled based on the measurement result by the temperature sensor, the film and the opening peripheral portion of the tray are matched with the temperature condition of the film itself. The amount of heat input to the overlapping portion with and can be made appropriate, and welding defects due to excess or deficiency of heating can be avoided.

[Brief description of drawings]

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

FIG. 2 is a vertical cross-sectional view of the packaging device.

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

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

FIG. 5 is a plan view of rollers.

FIG. 6 is a diagram showing a plane locus by the rotation of a roller.

FIG. 7 is an enlarged view of the vicinity of the flange of the tray when the rollers are in contact.

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

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

FIG. 10 is an operation diagram of the stretching mechanism.

FIG. 11 is an operation diagram of the stretching mechanism.

FIG. 12 is a top view of the packaging device showing an air flow when the axial fan operates.

[Explanation of symbols]

1 packaging equipment 3 rollers (heating means) 5 Film transport mechanism 8 Roller rotation mechanism (moving means) 9 Stretch mechanism 10 Control unit 31 heater 41 Temperature sensor 42 Axial fan (blower) 51 Film setting section (Film roll holding section) T tray f Flange (around the opening of the tray) Fm stretch film

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 3E049 AA01 AB03 BA04 DB02 EA01                       EB03 EC01 EC02 FA07                 3E094 AA04 AA16 BA04 BA12 CA02                       CA10 DA02 EA20 GA02 GA13                       GA21 HA08

Claims (5)

[Claims] 1. A top-seal wrapping device for a tray having an open upper part, wherein the opening is covered with a film in a state where an object to be packaged is accommodated in the tray, and the film is welded to a peripheral portion of the opening of the tray. A heating means for contacting and heating the periphery of the opening of the tray covered with a film, a moving means for moving the heating means along the periphery of the opening of the tray, and a temperature of the film directly A top-seal type packaging device comprising: a temperature sensor that measures indirectly or indirectly; and a control unit that controls at least one of the heating unit and the moving unit based on a measurement result by the temperature sensor. 2. A film roll holding unit for holding a film roll wound with the film delivered between the tray and the heating unit, wherein the temperature sensor is held by the film roll holding unit. The top-seal type packaging device according to claim 1, which measures an air temperature around the package. 3. The top according to claim 2, further comprising a blower for generating an air flow around the film roll, wherein the control unit further controls the blower based on a measurement result by the temperature sensor. Seal type packaging device. 4. The top seal type packaging device according to claim 3, wherein the blower is provided in the vicinity of the film roll held by the film roll holding portion. 5. The top-seal type packaging device according to claim 3, wherein the blower is provided in a space above the heating means or in the vicinity thereof.