JPH08156908A - Film sheet packing machine - Google Patents

Abstract

PURPOSE: To uniformly and certainly heat-seal a film by providing a pressure grasping member moved to the position where a film is wound around an article to be packed at least twice along with the article to be packed and grasping the film in cooperation with a heat sealer in a freely retreating state. CONSTITUTION: When the winding of a film F around an article W to be packed is started, the leading end of a film is held between the gripping rods 12a of a film gripper 12 and, subsequently, a film feeder 7 is revolved by the revolving driver attached to the ceiling part of a scull-shaped frame to wind the film F around the outer periphery of the article W. Next, a top sheet feeder is operated to cover the upper surface of the article W with a top film and, thereafter, the film feeder 7 is further revolved to bind the peripheral edge of the top sheet to the article W by the film F. A pressure grasping member 14 is erected at a predetermined point of time to wind the film around the pressure grasping member 14 and the article W integrally 2-3 times and the film is heat- sealed by a heat sealer 13.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a film sheet packing machine (hereinafter referred to simply as a packing machine). More specifically, it is a packing machine for packing the entire circumference of the product with a plastic film (hereinafter, simply referred to as a film) when the product is placed on a pallet and conveyed, and is the final processing of the packing. The present invention relates to a packing machine capable of efficiently and reliably heat-sealing a film.

[0002]

2. Description of the Related Art Conventionally, the following two types of packing machines are widely used. One is to place the product to be packed on the turntable while it is still on the pallet, and hold the tip of the film pulled out from the film roll with the gripper on the turntable close to the product, and then directly turn the turntable. There is a so-called turntable type packing machine that packs by rotating, and one is a film roll that holds the tip of the film pulled out from the film roll with a gripper while keeping the product on the fixed table. It is a so-called revolving type packing machine that packs a product with a wrap head that can revolve around the product.

In any of the packing machines, regardless of whether or not the film to be wound has adhesiveness, the trailing end side of the film is already wrapped at the end of winding the film on the product in order to prevent the film from peeling off. The film is pressed against the film by a heat-sealing machine and heat-sealed to bond the film. Then, after bonding, the rear end side is separated from the film roll.

[0004]

However, according to the above heat-sealing method, it is difficult to perform efficient and reliable adhesion for the following reasons. That is, if the surface of the product to be packaged is uneven, the portion of the film to be heat-sealed is also uneven, resulting in a gap between the wrapped film and the product to be packaged, or a corner of the product to be packaged. Part of the film to be heat-sealed may cause the film to stick out, resulting in incomplete adhesion when the heat-sealing machine is pressed, or when the film is partially pressed too strongly and the film has holes. , It may be torn.

Further, in the past, the heat sealing machine was heated by simply energizing it for a predetermined short time and was not for controlling the temperature thereof, which further promoted the occurrence of the above problems.

The present invention has been made to solve such a problem, and provides a packing machine capable of uniformly and surely heat-sealing a film by inserting a pinching member into a wound film. Is intended.

[0007]

A first aspect of a packing machine of the present invention is a base on which an object to be packed is placed, and a base around which the object to be packed is swung and lifted and lowered. Film supply frame, a film gripper installed on the base for holding and opening the film end, and heat for heat-sealing the film on the final circumference of the film wrapped around the object to be packed. It is characterized by comprising a sealing machine, and a pressing member that moves together with an object to be packaged at least twice around the film and presses the film with the heat sealing machine and can retract from the pressing position. .

[0008] It should be noted that the term "wound at least twice" does not mean that the object to be packed is completely rotated for two weeks, and the film to be pinched by the heat sealer and the pinching member is at least doubled. It means to be rolled.

A second aspect of the packing machine of the present invention is a turntable for placing and rotating an object to be packed,
A film supply frame installed outside the turntable, a film gripper installed on the turntable for holding and opening the film end portion, and a final circumference of the film wrapped around the object to be packed a plurality of times. A heat-sealing machine for heat-sealing the film, and a pinching member that moves to a position where it is wound by at least two-circle film together with the article to be pinched and presses the film with the heat-sealing machine, and can retract from the pinching position. It is characterized by comprising.

In both the first and second aspects,
In the heat-sealing machine, at a portion close to the welding portion for heat-sealing the films, a fusing striking portion for heating and fusing the film is provided, which does not require a special cutting tool and has a simple structure. Since it is possible to cut a portion of the film in the vicinity of the welded portion, it is preferable in that the equipment cost is reduced and the rear end of the film does not hang or project from the object to be packed. That is, it is possible to prevent the appearance of the packaged object from being impaired by the trailing end of the film that hangs or protrudes, or the package from being broken by being caught by another part.

Further, the heat sealing machine is provided with a protective roller which can reciprocate between a position slightly advanced from the heat sealing surface and a position retracted from the heat sealing surface.
The pinching member stands up at the pinching position several laps before the winding end of the film, the heat sealing machine moves so as to pinch the film with the pinching member after the film winding is completed, and the protective roller is The structure in which the film is pressed against the fusing line portion by its tension by retreating away from the film after heat-sealing makes it easy and linear to cut the rear end side of the film. It is preferable in terms.

The heat sealing machine is equipped with a temperature sensor, and the temperature sensor controls the heat sealing surface temperature of the heat sealing machine so as to be within a predetermined temperature range. This effectively prevents damage to the film. It is preferable because it is possible.

Further, in the film supply frame, a film roll accommodating portion and a film in a flat state stretched between the film roll and the object to be packed by moving in the axial direction of the film roll are provided on the side thereof. It is preferable to provide a film squeezing member for squeezing from the edge, because the film can be sandwiched by the film gripper over the entire width of the film, so that the film can be prevented from breaking and the heat sealing machine and the squeezing member can be made small. .

[0014]

According to the packing machine of the present invention, whether it is a swing packing machine or a turntable packing machine,
After the object to be packed is wrapped with the film, the trailing edge of the film is sandwiched between the pressing member and the heat sealer together with several windings (for example, 2 to 3 layers) of the film already wrapped around the object to be packed. Because it can be pressed and heat-sealed, no matter how uneven the surface of the item to be packed (for example, a plurality of cardboard boxes stacked unevenly), the part of the film to be heat-sealed is always Flattened, heated reliably and welded uniformly. Moreover, even if the trailing edge of the film is squeezed and a large number of wrinkles are generated, since the pressing member and the heat sealing machine clamp the film as described above, the portion of the film to be heat-sealed still remains. Flattened, heated reliably and welded uniformly.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of the packing machine of the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view showing an embodiment of the packing machine of the present invention, FIG. 2 is a perspective view showing the essential parts of the packing machine of FIG. 1, and FIG. 3 is heat of a heat seal device in the packing machine of FIG. FIG. 4 is a horizontal sectional view showing the sealing operation and the fusing operation, FIG. 4 is an explanatory view showing the operation of the heat sealing device in the packing machine of FIG. 1, and FIG. 5 is a plan view showing the top sheet feeding device in the packing machine of FIG. [Fig. 2] is a sectional view of a packaged item showing a packaged state by the packaging machine of Fig. 1.

In FIG. 1, reference numeral 1 is a swiveling type packing machine, and a placing table 3 for placing an article W to be packed is installed in the lower center of a turret-shaped frame 2 having four columns. .
The mounting table 3 is usually a part of a roller conveyor for transporting the articles W to be packed, for example, as shown in the drawing. The base in the claims means the frame 2, the mounting table 3 or a combination of these, respectively.

On the ceiling portion of the frame 2, a swing drive device 4 in which a reduction gear is connected to an output shaft of an electric motor is attached, and a swing beam mounted on the swing drive device 4 so as to extend in the horizontal direction. A vertical rail 5 hangs downward from the end of 4a. This vertical rail is 5
Can be swung around the article W to be packed by the swivel drive device 4 while maintaining a substantially vertical state. Further, the vertical rail 5 is provided with a film feeder 7 which can be moved up and down by chain drive by an electric motor. In this embodiment, the swivel drive device 4, the vertical rails 5, and the film feeder 7 constitute a film feeding frame referred to in the claims.

As shown in FIG. 2, a film roll 8 is detachably attached to the film feeder 7, and the plastic film F is pulled out from the film roll 8 by a guide roller 9 in a substantially flat state. . On the other hand, in the film feeder 7, the squeezing roller 1 that can reciprocate along the axis of the film roll 8 (and thus along the axis of the guide roller 9) in a portion close to the guide roller 9.
0 is provided. The reciprocating motion is performed by a known driving device such as a pneumatic cylinder. At the end of winding the film, when the film is not yet cut, the film F is stretched between the film roll 8 and the article W to be packed in a substantially flat plane, and the squeeze roller 10 is there. Is a so-called squeezing operation in which the squeezing roller 10 pushes the upper edge of the film F downward to narrow the film F while making wrinkles. Further, a sensor (not shown) for detecting the height of the article to be packaged, that is, the uppermost end of the article to be packaged is attached to the film feeder 7 toward the center of rotation.

Since the squeezing roller 10 is provided as described above, the width of the film F can be narrowed only near the portion to be heat-sealed. Therefore, the heat-sealing device can be downsized, and since the narrowed film portion does not wind around the object to be packed for several rounds, the surface of the object to be packed is not damaged.

A heat seal device 11 and a film gripper 12 are installed in the vicinity of the mounting table 3 described above.
The heat sealer 11 is equipped with a heat sealer 13 and a pinching member 14, and the pinching member 14 is close to the item to be packaged 2 to 3 turns before the end of winding the film F on the item to be packaged W. Stand up. Then, when the film F finishes winding the article W and the pinching member 14 together, the heat sealer 13 advances to pinch the two or three layers of the film F with the pinching member 14 for sheet sealing, and the film F. The rear end side is cut off.

The film gripper 12 is composed of a pair of holding rods 12a which are brought into contact with and separated from each other (hereinafter referred to as opening and closing) by a pneumatic cylinder (not shown), and further a pneumatic cylinder (not shown). The vertical position can be moved between the upper operating position and the lower retracted position. When the film is to be wrapped around the object to be packed, the tip of the film is clamped by the film gripper 12, and then the film feeder 7 is rotated to wind the film around the object to be packed.
The film gripper 12 is opened at the time when the film is wound up to three times, the film is unpinched, and the film is lowered to the retracted position.

As shown in FIG. 3, the heat sealer 13 has a large number of ridges (the tops of the ridges are made flat) on the heat-sealing surface 13a thereof, and is used for preventing adhesion of a melted film. It is a rectangular metal plate coated with a fluororesin.

The heating method is one in which a so-called rubber heater in which a metal foil generating Joule heat is patterned on a silicon rubber sheet is attached to the back surface (the surface opposite to the heat-sealing surface 13a) of the metal plate. . By adopting such a rubber heater 13b, its replacement becomes easy.

Although not shown in the figure, the heat sealer 13 is equipped with a known temperature sensor such as a thermostat, and the power of the heat sealer 13 is controlled to be stable within a predetermined temperature range by turning on and off the power. Is preferred.

The fluororesin coating is removed from one side edge (so-called a corner portion, hereinafter referred to as fusing cut portion 15) of the rear end side (film roll side) of the heat-sealing surface. Therefore, the fusing portion 15 becomes higher in temperature than the heat-sealing surface 13a, and since it is a corner portion, it is strongly pressed by the film F, so that the film pressed there is easily fused. That is, the heat sealer 13 also has a film cutter function.

The fusing line portion is not limited to the one using the side (corner portion) of the plate member as in this embodiment, but is actually formed as a ridge line along the longitudinal direction of the heat-sealing surface. You may. Furthermore, although not shown, in place of the above-mentioned fusing line portion, in the same position, or in consideration of the possibility that the final end of the film may be loosened, a position closer to the object to be packed is used for fusing. You may equip a heater. As the heater, a simple nichrome wire or the like stretched in a chordal shape of a bow, or a nichrome wire or the like built therein may be used. Immediately after heat sealing, this heater for fusing
For example, the protective roller 20 to be described later is automatically energized to raise the temperature at a suitable time after the retreat and the film fusing action is exerted.

As shown in a plan view of FIG. 4 (a) and a front view of FIG. 4 (b), the heat sealer 13 is rotatably supported by the main body 11a of the heat seal device 11, and The pneumatic cylinder 16 can rotate between a retracted position (horizontal posture) and an operating position (vertical posture). Then, after being moved to the operating position, it is pressed against the film wrapped around the article by another pneumatic cylinder 17a. On the other hand, the pressing member 14 has a flat rectangular plate shape, and the main body 11 of the heat seal device 11 is
It is pivotally supported at the tip of a link 18 pivotally supported by a. Then, the pneumatic cylinder 19 is used to link 1.
By swinging 8, the vertical movement can be made between the lower retracted position and the upper operating position. The pinching member is not limited to the one that moves up and down as in the present embodiment, and for example, the lower end of the pinching member is pivotally supported, and the operating position (upright state) and the retracted position (upright position) are set by the pneumatic cylinder or the electric motor. You may make it rock | fluctuate between (horizontal state).

The clamping member 14 is not limited to a rectangular plate shape, and for example, the corners are rounded so that the film is not broken by being caught during its movement, and the clamping member 14 has a long shape. It may be circular or the like.

As shown in FIG. 3, the heat sealer 13
Of the protective roller 2 in the vicinity of the side surface of the fusing line portion 15 side in
0 is provided. This protective roller 20 is the fusing section 1
5, which is a long roller extended along the axis 5, and is rotated by the pneumatic cylinder 16 together with the heat sealer 13 between the retracted position (horizontal posture) and the operating position (vertical posture). Then, the heat sealer 13 at the operating position is slightly advanced to the film side from the heat seal surface 13a. With the protective roller 20, the heat sealer 13
It is possible to prevent the film from being inadvertently contacted with the heat seal surface 13a or the fusing cut portion 15 and being damaged or cut when the film stands up to its operating position.

After the heat sealer 13 is pressed against the film wrapped around the object to be welded to finish welding the film, the protective roller 20 is moved to the pneumatic cylinder 17b (see FIG. 4).
(See also (b)), and moves in the direction away from the article to be packed. As a result, the film F stretched between the heat sealer 13 and the film roll 8 is pressed against the fusing cut portion 15 by its own tension. By doing so, the fusing of the film becomes easier.

Alternatively, if the above-mentioned film fusing heater is provided, the fusing is easily performed by this heater.

As shown in FIG. 1, a so-called ceiling of the frame 2 is provided with a top sheet feeding device 21. Since only the side peripheral surface of the article to be packed can be lapped only by the film feeder 7, the top sheet feeding device 2
1, the top surface of the item to be packed is polyethylene film, etc.
A top sheet made of the same material as the film is used for wrapping.

As shown in FIG. 5, the top sheet feeding device 21 is provided with a pair of support rails 22 along two opposite sides of the ceiling of the frame 2. FIG. 5 is a view of the main packing machine 1 viewed from above. The pair of support rails 22 are raised and lowered synchronously by chain drive. And
A long top sheet roll 23 is removably bridged between the ends of the pair of support rails 22. In addition, a rail 25 for a cutter in which a so-called cutter 24 can reciprocate in parallel with the mounted top sheet roll 23.
Has been bridged. Further, each of the support rails 22 is provided with a top sheet gripper 26 that can move along the support rails 22 synchronously by chain drive. The grippers 26 move on the support rails 22 to approach the top sheet roll 23, grip both sides of the leading edge of the top sheet, and then move in a direction away from the top sheet roll 23 as they are to move the top sheet. Pull out the top sheet T from the roll 23. When the top sheet T is pulled out by a predetermined length, the cutter 24 is moved from one side edge of the top sheet T to the other side edge by the chain drive to cut the top sheet T. Simultaneously with this cutting, the two grippers 26 release the leading end of the top sheet, so that the top sheet T having a predetermined length falls so as to cover the top surface of the article W to be packed. When the height sensor provided in the film feeder 7 detects the height of the article to be packed as described above, the support rail 22 is slightly above the height with reference to the height. Can be lowered. As a result, the top sheet T covers the top surface of the article to be packed well.

Next, the operation of the packing machine 1 will be briefly described.

First, when the film is to be wrapped around the object to be packaged as described above, the leading end of the film is clamped by closing the clamping rod 12a of the film gripper 12, and then the swivel drive device 4 is used to move the film feeder 7 to the film feeder 7. Turn.

The turning of the film supplier 7 starts near the lower end of the object to be packed, and the film is wound around the object to be packed as the film supplier 7 turns. The film gripper 12 is opened at the time when the film gripper 12 is wound two to three times to release the pinch of the film and descend to the retracted position.

Next, while the film feeder 7 continues to turn, the height sensor (not shown) detects the upper end of the article to be packed, and at that time, the film feeder 7 temporarily stops the turn. .

Then, the top sheet supply device 21 descends slightly above the height of the article to be packed, the top sheet T is pulled out by the gripper 26 as described above, and is cut by the cutter 24 to cover the top surface of the article to be packed. . After that, the film feeder 7 further rotates to bind the peripheral edge of the top sheet T to the object to be packed with a film.

Still further, the film feeder 7 turns and descends.

As described above, since the top sheet is covered during the film winding, the cross section of the package after the packaging is completed is as shown in FIG. For easy understanding, FIG. 6 shows the films F wound around the article W and the top sheet T and the like with a large gap. As is apparent from the figure, even if moisture is accumulated on the top sheet T for some reason, the article to be packed is not wet by moisture as in the conventional case because of the lower film Fu. Moreover, since the top sheet can be attached during the film winding process, there is no need for a separate process and space as in the conventional case. Fo indicates an upper layer film. The film Fu of the lower layer is wound while the film feeder is rising, and the film Fo of the upper layer is wound while the film feeder is lowered after covering the top sheet.

The film feeder 7 reaches the bottom end,
The pinching member 14 stands up at a point two to three turns before the end of film winding. The film feeder 7 continues to rotate, and the pressing member 14 and the object to be packaged are wound around the film by a few turns, and then stopped.

Next, the squeezing roller 1 of the film feeder 7
0 descends to squeeze the film, and subsequently the film gripper 12 stands up to sandwich the squeezed portion of the film.

At the same time as or before the standup of the film gripper 12, the heat sealer 13 and the protective roller 20 stand up integrally.

Then, the heat sealer 13 advances toward the object to be packed and presses the film of two or three layers with the pressing member 14 to heat seal. Immediately thereafter, the protective roller 20 retreats, and the film F stretched between the heat sealer 13 and the film roll 8 is pressed against the fusing cut portion 15 by its own tension. After that, the heat sealer 13 separates from the film and falls to the retracted position together with the protective roller 20, so that the film is melted more easily.

Although only the so-called swivel type packing machine has been described in the above embodiment, the features of the present invention can be applied to the so-called turntable type packing machine as it is. That is, in the turntable type packing machine, the turning drive device 4 and the vertical rails 5 are not provided, and the film feeder 7 is fixed to the outside of the turntable.

The pressing member 14 and the film gripper 12 are provided on the turntable. The heat seal device 11 may be provided on the turntable or may be fixed outside the turntable. It will be apparent that such a configuration can achieve the same effects as the swivel packaging machine 1.

[0048]

According to the present invention, the film trailing end side at the end of winding can be uniformly and surely heat-sealed to the film already wound. As a result, there is no risk that the package will be unraveled or torn from the heat-sealed portion.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a packing machine of the present invention.

FIG. 2 is a perspective view showing a main part of the packing machine of FIG.

FIG. 3 is a horizontal sectional view showing a heat sealing operation and a fusing operation of the heat sealing device in the packing machine of FIG.

FIG. 4 is an explanatory view showing the operation of the heat seal device in the packing machine of FIG.

5 is a plan view showing a top sheet supply device in the packing machine of FIG. 1. FIG.

FIG. 6 is a cross-sectional view of a packaged item showing a packaging state by the packaging machine of FIG.

[Explanation of symbols]

 1 ... Packing machine 2 ... Frame 3 ... Mounting table 7 ... Film feeder 8 ... Film roll 10 ... Squeezing roller 11 ... Heat sealing device 12 ... Film gripper 13 ... Heat sealer 14 ... Clamping member 15 ... Fusing section F ... Film T ... Top sheet

Claims (6)

[Claims] 1. A base for placing an object to be packed, a film supply frame capable of rotating around the object to be packed on the base and moving up and down, and a film end installed on the base. A film gripper for sandwiching and opening the film, a heat sealing machine for heat-sealing the film on the final circumference of the film wrapped around the film to be packaged a plurality of times, and a position where the film is wound at least two times together with the film to be packaged. A film sheet packing machine comprising: a pressing member that moves to a position and presses the film with the heat sealing machine and can retract from the pressing position. 2. A turntable for placing and rotating an object to be packed, a film supply frame installed outside the turntable, and a film end installed on the turntable for clamping the film end portion. A film gripper for opening, a heat-sealing machine for heat-sealing the film of the final circumference on the film wrapped around the object to be packed, and a position to be wound with at least two wrapping films together with the object to be packed. A film sheet packing machine comprising a heat-sealing machine and a pinching member capable of pinching a film and retracting from a pinching position. 3. The film according to claim 1, wherein the heat-sealing machine has a fusing line portion for heat-fusing the film at a portion close to a welding portion for heat-sealing the films. Sheet packing machine. 4. The heat sealing machine has a protective roller that can reciprocate between a position slightly advanced from the heat sealing surface and a position retracted from the heat sealing surface, and the pinching member is a film winding member. A few laps before the end, it stands up at the pinching position, the heat sealing machine moves so as to pinch the film with the pinching member after the end of film winding, and the protective roller separates from the film after heat sealing. 4. The film sheet packing machine according to claim 3, wherein the film is pressed against the fusing line portion by its tension by retreating. 5. The heat sealing machine is equipped with a temperature sensor, and the temperature sensor is configured to control the heat sealing surface temperature of the heat sealing machine to fall within a predetermined temperature range. Film sheet packing machine. 6. A film in a flat state stretched between the film roll and an object to be packed by moving the film supply frame in the axial direction of the film roll accommodating portion and the film roll. The film sheet packing machine according to claim 1 or 2, further comprising a film drawing member for drawing from the edge.