JPH10230911A - Drawing device of film in stretch film packaging machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To sufficiently secure the superposed part of film folded into the underside of an article to be packaged regardless of the size of the article and prevent the film from sticking to the outside of the article, by selectively actuating an auxiliary drawing means in accordance with the size of the article. SOLUTION: The distance L between the sending-out end E1 of an article 22 to be packaged and a cutting position E2 of film is set on the basis of not the maximum article size but the middle article size. Stretch film 12 is drawn to the packaging position by use of a drawing body 20, for articles smaller than the middle size and the drawing body 20 is transferred to the longest transferable position and the film 12 is superfluously drawn out of a base roll 10 by the action of a drawing roller 62, for articles larger than the middle size. Accordingly, even if the article size is smaller or larger than the middle size, the initial purpose can be achieved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stretch film having a predetermined length which is pulled out from a supply source and stretched and held substantially horizontally at a packaging position. The present invention relates to a film drawing device in a stretch film packaging machine that covers an upper side with a stretch film, and then wraps the film by folding a film extension portion that extends outward from the periphery of the packaged object to the lower side of the packaged object. .

[0002]

2. Description of the Related Art A stretch film wrapping machine using a stretch film has been conventionally known as a wrapping machine for tightly wrapping an article to be wrapped on a container such as a tray with a film. As shown in FIG. 11, this stretch film wrapping machine can be sandwiched by a support mechanism 16 capable of supporting the stretch film 12 on the front side in the film withdrawing direction of a guide roller 14 for guiding the stretch film 12 drawn from the raw roll 10. The holding mechanism 18 and the drawer 20 are arranged in series, and the drawer 20 has an amount corresponding to the size (length in the film drawing direction) of the article 22 to be packed while holding the start end of the stretch film 12. It is configured to move only horizontally. Further, a cutter 24 that moves up and down across the drawing-out path of the stretch film 12 is provided between the support mechanism 16 and the holding mechanism 18, and the stretch film 12 facing between the support mechanism 16 and the holding mechanism 18 is It is configured to be cut by the cutter 24.

A supply conveyor 26 running parallel to the moving direction of the drawer 20 is provided below the stretch film 12 which is pulled out by the drawer 20 and faces the packing position between the holding mechanism 18 and the packing film 18 substantially horizontally. It is arranged.
The supply conveyor 26 includes a plurality of attachments 28 that are separated in the traveling direction, and is configured to supply the articles 22 to the vertically movable article receiving table 30 located directly below the packaging position by the attachments 28. .

That is, in the packaging machine, the drawer 2
When the stretch film 12 is pulled out from the material roll 10 by a predetermined amount according to 0, and the vicinity of the rear end in the pulling direction is held by a holding mechanism 18, the film 12 is stretched and held substantially horizontally at the packaging position. The article 22 to be packaged is transported by the supply conveyor 26, and the article 22 to be packaged is transferred to the article receiving table 30 located immediately below the packaging position. After the stretch film 12 facing between the support mechanism 16 and the holding mechanism 18 is cut by the cutter 24, the article receiving table 3 is cut.
0 is raised to push up the packaged object 22 from below with respect to the stretch film 12 stretched and held at the packaging position, so that the upper side of the packaged material 22 is covered with the film 12. Next, the holding by the holding mechanism 18 and the drawer body 20 is released, and the four extending portions of the stretch film 12 extending outward from the peripheral edge of the to-be-packaged 22 are folded by unfolding means (not shown). The packaging is completed by folding and folding the lower side.

[0005]

In the above-described packaging machine, each of the stretch films 12 extending outward from the right and left sides of the peripheral edge of the packaged object 22 at the rear side of the film withdrawal direction and at the intersection with the withdrawal direction. After the protrusion is folded under the packaged object 22 by the movable folding member,
In the process of carrying out the packaged article 22 to the front side in the film withdrawing direction, a film extension portion extending outward from the front edge in the film withdrawal direction by the fixed folding member is folded under the packaged article 22. Have been. Further, by setting the transport direction of the packaged object 22 on the supply conveyor 26 to be opposite to the film drawing direction, the supply conveyor 26
The supply side of the packaged articles 22 to the supply side and the unloading side of the packaged articles 22 are the same, so that the packaging operation can be performed efficiently.

[0006] In the above-described packaging machine in which the carrying-out direction of the packaged object 22 and the drawing-out direction of the drawer body 20 are set to be the same, regardless of the size of the packaged product 22,
0 is an end (out end) E ₁ carry-out side of the packaged articles 22 which has reached the wrapping position is moved upward, the packaged articles relative to the fixed folding member to an article receiving stand 30 so as to reach the fixed position 22 Is set. In other words, the package 22
Even if the size of the packaged object 2 is different as shown in FIG.
Cutting position of the second discharge end E ₁ and stretch film 12 by the cutter 24 spaced a distance L between (film cutting position) E ₂ is always constant, the upper surface of the packaged articles 22, wound on the surface and the lower surface of the pull-out direction rear side The length of the stretch film 12 to be applied was constant.

In this case, if the distance L between the discharge end E ₁ of the packaged object 22 and the film cutting position E ₂ is set according to the small-sized packaged object 22 to be packaged by the packaging machine, When the large-sized packaged object 22 is wrapped, the extension 12b on the front side in the film withdrawal direction of the stretch film 12 folded below does not overlap with the extension 12a on the rear side in the film withdrawal direction. May occur. Therefore, the length of the rear extension 12a of the stretch film 12 wound on the lower side of the large-sized packaged object 22 conventionally packaged by the packaging machine is shown in FIG. as, so as to obtain sufficiently the overlapping portion of the front extending portion 12b under side during packaging, unloaded end E ₁ of the packed material 22 and the film cutting position E ₂
Has been set to the distance L. However, in this case, the rear extending portion 12a folded downward is too long for the small-sized packaged object 22, and when the front extending portion 12b of the stretch film 12 is folded, 1
As shown in FIG. 2 (b), the rear extension 12a is folded back, and the folded portion does not fit within the lower surface of the package 22 and protrudes outside the package 22. There is. Further, the distance L becomes longer in order to set the distance L between the discharge end E ₁ and the film cutting position E ₂ in accordance with the object to be packaged 22 of larger size, is also pointed out difficulties entire device is lengthening You.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned drawbacks inherent in the prior art, and has been proposed to solve the problem suitably. Provided is a film pull-out device in a stretch film packaging machine capable of sufficiently securing an overlapping portion of a film folded below a package and preventing the film folded below from protruding outside a package. The purpose is to do.

[0009]

SUMMARY OF THE INVENTION In order to overcome the above-mentioned problems and achieve the intended object, the present invention holds a starting end of a stretch film drawn from a supply source and adjusts the length of the stretched film according to the size of an article to be packaged. Drawer means for moving the stretch film to the packaging position by moving the stretch film substantially horizontally, holding means for holding the stretch film drawn by the drawer means in the vicinity of the rear end in the drawing direction, and an arrangement position of the holding means. A cutter that is disposed on the rear side in the drawing direction and cuts the stretch film, and is disposed below the packaging position,
A push-up unit for pushing up the packaged object toward the stretch film stretched and held by the drawing unit and the holding unit; and a film extending portion extending outward from the periphery of the packaged object. In a stretch film wrapping machine comprising a folding means for folding underneath, a draw-out assisting means movable in a direction crossing a stretch film drawing-out path is provided between a cutting position of the stretch film by the cutter and a holding means. After the stretch film is drawn out by the draw-out means, the stretch film is further drawn out from the supply source by moving the draw-out assisting means, and the film drawing direction rear side after cutting the stretch film with respect to the packaged object. The length of the film extending portion facing the front end can be changed.

[0010]

The stretch film that has been drawn from the supply source is drawn out to the packaging position by a predetermined length by a drawer,
The stretch film is stretched and held at the packaging position by being clamped by the clamping mechanism in the vicinity of the end portion in the drawing direction.
After the stretch film is cut by the cutter, the object to be packaged is pushed up from below toward the stretch film stretched and held at the packaging position, so that the upper side of the object to be packaged is covered with the film. Next, the packaging is performed by folding the extension of the film extending outward from the peripheral edge of the package to the lower side of the package. When lengthening the film extending portion extending from the peripheral edge on the rear side of the film withdrawal direction of the packaged object, before cutting the stretch film with the cutter, actuate the withdrawal assisting means to remove the stretch film from the supply source. Withdraw. By cutting the stretch film with the cutter, the extending portion of the film extending from the peripheral edge on the rear side in the film withdrawal direction of the article to be packaged becomes longer. That is, by selectively operating the draw-out assisting means in accordance with the size of the article to be packaged, it is possible to wrap the film with the extending portions of the film always overlapping well below the article to be packaged.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Next, a description will be given of a film drawing device in a stretch film packaging machine according to the present invention with reference to a preferred embodiment. The same members as those described in the related art with reference to FIG. 11 are denoted by the same reference numerals.

As shown in FIG. 1, a stretch film 12 drawn from a material roll 10 serving as a supply source is fed to a support mechanism 16 via a guide roller 14. The support mechanism 16 is provided between a pair of holding members 34, 34 disposed on the machine frame 32 so as to be spaced apart in a width direction intersecting with the film unwinding direction, and a pair of vertically opposed rollers 36, 36. It is provided with a pair of support plates 38, 38 which are disposed on the front side in the film pull-out direction from the position where the rollers 36, 36 are disposed, and which are vertically opposed. The stretch film 12 is supported between the upper roller 36 and the support plate 38 and the lower roller 36 and the support plate 38 in a state where the stretch film 12 can be pulled out. As shown in FIG. 2, the support plates 38, 38 are formed in a comb shape in a plan view, and the starting ends of the stretch films 12 supported by the support plates 38, 38 do not interfere with the drawer 20 described later. It is constituted so that it can be clamped without.

A cutter 24 extending in the width direction crossing the film withdrawing direction is provided at a position away from the support mechanism 16 in the film withdrawing direction front side.
It is arranged to move up and down integrally with the zero. When the cutter 24 moves from the standby position (FIG. 3) facing the lower side of the film path to the upper operating position (FIG. 4), the stretch film 12 is moved over the entire length in the width direction at the front side of the support mechanism 16. It is configured to cut.

A clamping mechanism 18 as clamping means for clamping the stretch film 12 from above and below is disposed on the front side of the cutter 24 in the film withdrawing direction. The holding mechanism 18 is composed of a fixed plate 40 arranged and fixed above the film path and extending in the width direction, and a movable plate 42 arranged below the film path so as to be movable up and down and facing the fixed plate 40. The movable plate 42 is connected to an appropriate drive source (not shown).
By moving from the lower standby position (FIG. 3) away from the operating position (FIG. 4) in contact with the fixed plate 40,
Between the two, the vicinity of the rear end of the stretch film 12 in the film withdrawing direction is sandwiched. In a state where the movable plate 42 faces the standby position, the drawer 20 described later is set so as to pass between the plates 40 and 42 and approach the support mechanism 16.

The support mechanism 1 passes between the fixed plate 40 and the movable plate 42 which are vertically separated from the holding mechanism 18 to the front side in the film drawing direction from the position where the support mechanism 16 is disposed.
A drawer body 20 is provided as drawer means that can move horizontally close to and away from the drawer 6. This drawer body 20
Is composed of an upper plate 46 located on the upper side of the film path and a lower plate 48 located on the lower side.
2 is configured to sandwich the start end. Note that the lower plate 48 is disposed on the upper plate 46 so as to be openable and closable, and the opening and closing mechanism 50 moves the lower plate 48 up and down with respect to the upper plate 46, thereby holding and releasing the film 12. I have. As shown in FIG. 2, the lower plate 48 is formed in a comb shape that does not interfere with the comb teeth of the support plates 38, 38 of the support mechanism 16, and the starting end of the stretch film 12 supported by the support plates 38, 38. Is sandwiched between the upper and lower plates 46, 48.

As shown in FIG. 2, a pair of guide shafts 52, 52 parallel to the film withdrawing direction are provided at positions spaced apart in the width direction across the film path of the machine frame 32. An upper plate 46 of the drawer body 20 is slidably provided therebetween. Further, at a position close to each guide shaft 52, an endless belt 56 wound around pulleys 54, 54 rotatably supported on the machine frame 32 while being separated back and forth in the film unwinding direction faces freely, The upper plate 46 is fixed to an appropriate position of the endless belt 56. One pulley 54
Is driven to rotate by a drive source (not shown) such as a servomotor, and is configured to horizontally move the drawer body 20 between a clamping position close to the support mechanism 16 and an operating position separated therefrom. That is, after the drawer body 20 arrives at the holding position and holds the start end of the stretch film 12 supported by the support mechanism 16, the drawer body 20 is moved to the operating position, so that the film 12 has a predetermined length. Only fabric roll 1
It is designed to be drawn from zero and spread to the packaging position.
The operating position of the drawer body 20 is basically changed depending on the size of the packaged object 22 (length in the film drawing direction). However, the stretch film 12 is drawn out extra by the drawer roller 20 as described later. In such a case, it is set to be always at the same position. Also, in FIG.
Denotes side holding means for holding the stretch film 12 drawn out to the packaging position on both sides in the width direction and holding the stretch film 12 in an extended state.

As shown in FIG. 2, a pair of support arms 58, 58 separated in the width direction sandwiching the film path of the stretch film 12, pivotally support the machine frame 32 via a shaft 60 so as to be vertically swingable. Is done. The front ends of the arms 58, 58 that are separated from the pivotal support portion are located at the film cutting position E ₂ of the stretch film 12 by the cutter 24 and the holding mechanism 1.
8, and a draw-out roller 62 as a drawing-out assisting means of the stretch film 12 is provided between the front ends thereof. As shown in FIG. 3, one end of a connecting rod 64 is pivotally supported by one support arm 58, and the other end of the connecting rod 64 is deviated from the center of rotation of a disk 68 driven to rotate by a drive motor 66. It is pivoted at the position where it was. That is, by rotating the disk 68 in a required direction by the drive motor 66, the pull-out roller 6 is rotated.
2 is configured to move up and down between a standby position (FIG. 3) facing above the film path and an operating position (FIG. 4) below the film path. Then, while the stretch film 12 is being held by the holding mechanism 18, the draw roller 62 is moved from the standby position to the operating position, whereby the stretch film 12 is drawn from the raw roll 10.

A notch 68a is formed in the disk 68, and a notch 68a is formed in a bracket (not shown) on which the drive motor 66 is disposed on both sides of the rotation center of the disk 68. Sensors 70 and 72 for detection are provided, and the setting is made such that when the sensors 70 and 72 detect the notch 68a, the drive motor 66 is controlled to stop. That is, one sensor 70 detects the notch 68a when the pull-out roller 62 faces the standby position, and the other sensor 72 detects the notch 68a when the pull-out roller 62 reaches the operating position. It is set as follows.

Below the packaging position, as shown in FIG. 1, a supply conveyor 26 is disposed so as to run freely. The supply conveyor 26 includes a plurality of attachments 28 that are separated from each other at predetermined intervals in the traveling direction.
8 is configured to convey the article to be packaged 22 directly below the packaging position. Further, downstream of the supply conveyor 26 in the traveling direction, an article receiving table 30 serving as a lifting means is disposed at a position directly below the packaging position so as to be able to move up and down, and the articles 22 conveyed by the supply conveyor 26 It is designed to be transferred to the receiving table 30. The article receiving table 30 is set to move upward to an upper position beyond the film path by an operation mechanism (not shown), and the stretched film 12 is pushed up by the packaged object 22 placed on the receiving table 30 so that the upper surface thereof is turned on. It is configured to cover. In addition, the supply conveyor 2
6 and the pulling-out direction of the drawer body 20 are set to be opposite to each other, and the end of the packaged object 22 transferred to the article receiving table 30 on the unloading side at the time of film packaging described later ( and unloading end) E _1, the distance L between the film cutting position E ₂ of the stretch film 12 by the cutter 24
Is set to be always constant (see FIG. 1).

As shown in FIG. 1, an article pressing plate 74 is disposed above the packaging position in the machine frame 32, and is pushed up by the article receiving table 30 below the article pressing plate 74. An article carrying-out member 76 for carrying out the packaged object 22 to the front in the film withdrawing direction is provided movably in the front-rear direction. The machine frame 32 is provided with the packaged object 2 at a position facing below the packaged object 22 when the article receiving table 30 is moved upward.
2, a rear folding member (folding means) 78 for folding a film extension portion (rear extension portion) 12a extending outward from the rear edge of the rear side in the film withdrawing direction to the lower side of the packaged object 22. Left and right side folding members that are disposed movably in the front and rear directions and that fold the film extending portions extending outward from the right and left peripheral edges crossing the film drawing direction to the lower side of the packaged object 22. (Folding means) 80, 80 (only one is shown) are provided so as to be rotatable in the horizontal direction. The rear fold member 78 and the left and right side fold members 80, 80 are linked to each other via a link mechanism (not shown) so that the rear fold member 78 moves in the front-rear direction. The folding members 80, 80 are configured to open and close and fold the film extending portions extending outward from the rear side and the left and right peripheral edges of the article 22 to be folded below the article 22.

A front folding member (folding means) 82 is arranged and fixed to the machine frame 32 on the side opposite to the rear folding member 78 with the packaged object 22 pushed up by the article receiving stand 30 interposed therebetween.
When the article to be packaged 22 is carried out by the article carrying-out member 76, the front folding member 82 causes the film extending section (the front extending section) to extend outward from the peripheral edge of the packaged article 22 in the film withdrawing direction front side. ) 12b is folded under the packaged object 22. In addition, a heater 84 is provided forward of the disposition position of the front folding member 82 in the unloading direction,
Packaged object 22 that has passed the position where front folding member 82 is provided
Is placed on the heater 84, so that the film overlapping portion on the lower side of the packaged object 22 is thermally welded.

The article 2 to be packaged in the supply conveyor 26
An article sensor 86 for detecting the article to be packaged 22 is disposed on the conveyance path 2 and the sensor 86 is detected by a control device (not shown).
The size of the package 22 (the length in the film pull-out direction) is obtained based on the detection time of the package 22 by the above. Then, in the control device, based on the obtained size of the packaged object 22,
The film wrapping length required for wrapping according to the size is obtained, and a command is issued to the drive source of the drawer 20 to move the drawer 20 by an amount corresponding to the film wrapping length. The length of the film package is compared with a predetermined value to determine whether or not to operate the pull-out roller 62. When the pull-out roller 62 is to be operated, an operation command and a return command are issued to the drive motor 66 at appropriate timing. You. The packaging machine has a pulse generator (not shown) that generates a pulse corresponding to the rotation of an appropriate rotating shaft, and various timings are determined by counting the number of pulses from the pulse generator. It has become so.

[0023]

Next, the operation of the film drawing apparatus according to the embodiment will be described. In the embodiment, the packaged object 2
2 of unloading end E ₁ and the distance between the film cutting position E ₂ L
Is set according to, for example, the medium-sized packaged object 22 instead of the largest-sized packaged object 22 to be packed by the packaging machine. In the packaging machine, the moving range of the drawer body 20 is set so that the moving amount of the drawer body 20 corresponding to the film packaging length in the medium-sized packaged object 22 is obtained. The stretch film 12 is pulled out to the packing position using only the drawer body 20 for the packaged object 22 having the following dimensions. Note that the movement amount of the drawer body 20 with respect to the packaged object 22 having the intermediate dimension is the longest movement amount. Then, when packing a packaged object 22 larger than the medium-sized packaged object 22, the controller determines that the film packaging length is longer than the film-packing length of the medium-sized packaged object 22, It is set so that the drawer body 20 moves to the position where the longest movement amount is obtained, and at the same time, the drawer roller 62 is operated to draw out the stretch film 12 extra from the raw roll 10. In the standby state of the packaging machine, the starting end of the stretch film 12 drawn from the raw roll 10 is supported between the upper and lower support plates 38 of the support mechanism 16. Further, the cutter 24, the movable plate 42 of the holding mechanism 18 and the pull-out roller 62 face the standby position, respectively, and
0 faces the operating position.

(Case of Packaging Intermediate Dimensions or Smaller Dimensions) When the packages 22 are placed on the supply conveyor 26, the detection signal of an article supply detection sensor (not shown) is controlled. The output is output to the device, and the operation of the packaging machine is started. That is, the supply conveyor 26 travels, and the article to be packaged 22 is transported downstream by the attachment 28 and is transferred to the article receiving table 30 (see FIG. 5). During the conveyance of the package 22 by the supply conveyor 26, the size of the package 22 is obtained based on the detection time of the package 22 by the article sensor 86, and the movement of the drawer 20 from the holding position is determined. The quantity (operating position) is set. Also, since the film packaging length required for packaging according to the size of the packaged object 22 is determined to be less than or equal to the film packaging length for the medium-sized packaged object 22 described above, Is not output.

After the start of the operation of the packaging machine, the drawer body 20 moves toward the holding position and holds the starting end of the stretch film 12 supported by the support mechanism 16, and then the driving source is controlled by the control device. Then, the drawer body 20 horizontally moves forward in the pull-out direction by an amount corresponding to the size of the packaged object 22. When the drawer body 20 reaches the predetermined operation position and stops, the movable plate 42 of the holding mechanism 18 moves from the standby position to the operation position, thereby holding the stretch film 12 in the vicinity of the rear end in the film drawing direction. . The left and right side ends of the film 12 are also held by the side holding means 57, 57, so that the stretch film 12 is held in an expanded state at the packaging position.

The article receiving table 3 on which the article 22 has been transferred.
6, the stretched film 12 stretched at the packaging position is pushed up and stretched by the packaged object 22 as shown in FIG. Position). In addition, the cutter 24 that moves up and down integrally with the article receiving table 30 moves from the standby position to the operating position with the upward movement of the article receiving table 30, so that the distance between the support mechanism 16 and the holding mechanism 18 is increased. Is cut off.

While the article receiving table 30 is stopped at the upper moving end, the rear folding member 78 moves forward, and the left and right side folding members 80, 80 come close to each other, so that the article 22 Rear extension 12 extending outward from the rear edge of
a and the film extending portions extending outward from the peripheral edges on both the left and right sides are respectively folded under the packaged object 22. At this time, the film holding by the holding mechanism 18 and the side holding means 57, 57 is released at an appropriate timing.

When the rear folding member 78 moves forward,
The article to be packaged 22 is transferred onto the rear folding member 78, and the article carrying-out member 76 moves forward toward the heater 84, so that the article to be packaged 22 is carried out toward the front folding member 82. At this time, the film holding of the drawer body 20 is released at an appropriate timing, and the front extension 12b extending outward from the front peripheral edge of the packaged object 22
2 is folded downward when passing over the front folding member 82, and the packaging is completed (see FIG. 7). When the article 22 is unloaded by the article unloading member 76 and transferred onto the heater 84, the film extending portion folded and overlapped below the article 22 is thermally welded, and Is considered to be strong.

In this case, the discharge end E of the packaged object 22
₁ and the distance L between the film cutting position E ₂ are, because they are set in accordance with the object to be packaged 22 of intermediate size, smaller even be packaged 22, to be packaged the front extending portion 12b 2
When folded downward, the rear extension portion 12a is not folded back and does not protrude outside the packaged object 22.
Further, it is possible to shorten the distance L in order to set the distance L between the discharge end E ₁ and the film cutting position E ₂ in accordance with the object to be packaged 22 of intermediate dimensions, may render the entire apparatus compact.

(Concerning Packaging of Packaged Object of Larger Dimension than Package of Intermediate Size) While the packaged item 22 is being conveyed by the attachment 28 of the supply conveyor 26, the packaged object 22 is detected by the article sensor 86. Is required. Since it is determined that the film packaging length required for packaging according to the obtained size of the packaged object 22 is longer than the film packaging length for the medium-sized packaged object 22, the drawer body 20 from the nipping position of the drawer 20 is determined. The moving amount (operating position) is set to the longest moving amount, and the operation command and the return command to the drive motor 66 of the draw-out roller 62 are output at appropriate timing.

Drawer 2 waiting at the previous operating position
0 moves to the holding position, and after the starting end of the stretch film 12 supported by the support mechanism 16 is held, the drawer 20 moves horizontally by the longest amount of movement in the drawing direction forward (see FIG. 8). ). When the drawer body 20 reaches a predetermined operating position and stops, the movable plate 42 of the holding mechanism 18 moves from the standby position to the operating position, thereby holding the stretch film 12 near the rear end. The left and right side ends of the film 12 are also held by the side holding means 57, 57.
Thus, the stretch film 12 is held in the stretched state at the packaging position. Further, after the clamping mechanism 18 clamps the vicinity of the rear end of the stretch film 12, an operation command is output to the drive motor 66, and the pull-out roller 62 moves from the standby position to the operation position via the support arms 58, 58. 4 and 9, the draw-out roller 62 comes into contact with the stretch film 12 facing between the support mechanism 16 and the sandwiching mechanism 18 from above and pushes down the stretch film 12, and the stretch film 12 is stretched from the raw roll 10. The film 12 is pulled out extra. The draw-out roller 62 is
When the sensor 72 detects the notch 68a of the disk 68, it stops at the operating position.

The article receiving tray 3 on which the article 22 has been transferred.
0, the pull-out roller 20 and the support mechanism 16
Then, the stretch film 12 is cut. In other words, when packaging the packaged object 22 having a large size, the stretch film 12 having a length obtained by adding the extra length drawn by the movement of the pull-out roller 62 to the length drawn by the longest movement amount of the drawer body 20 is used. used. And
After the stretch film 12 is cut, a return command is output to the drive motor 66, the drawer roller 62 returns to the standby position, and the sensor 70 detects the notch 6 in the disk 68.
The operation is stopped by detecting 8a.

Thereafter, in the same manner as described above,
Stretch film 1 that extends outward from the rear edge
2 extending portions 12a and the extending portions of the stretch film 12 extending outward from the left and right peripheral edges are placed under the package 22 by a rear folding member 78 and side folding members 80,80. After being folded, the article 22 is carried out by the article carrying-out member 76 toward the heater 84, so that the extending portion 12b of the stretch film 12 extending outward from the peripheral edge on the front side of the article 22 is formed. Then, the package 22 is folded under the front folding member 82 (see FIG. 10). Then, the article to be packaged 22 is transferred to the heater 84, and the film overlapping portion under the sheet is thermally welded, so that the packaging is strengthened.

As described above, when wrapping an object 22 having a large size, since the stretch film 12 is extraly pulled out and wrapped by the draw-out roller 62, the wrapped object 22 is folded under the same. The front extension 12b and the rear extension 12a to be inserted can be sufficiently overlapped. In addition, the movement amount of the drawer body 20 is the longest movement amount corresponding to the packaged object 22 of the intermediate size in which the separation distance L is set, so that the longest movement amount of the drawer body 20 is shorter than the conventional case. It becomes possible to do so.

In the embodiment, the stretch film is pulled out extra by swinging the draw roller up and down. However, the roller may be moved up and down across the film path by a linear actuator such as a cylinder. Good. Further, the cutter can be moved up and down by independent driving means.

In the above embodiment, the case where the operating position of the pull-out roller is set to one position has been described. However, by increasing the number of sensors for detecting the operating position, a plurality of operating positions of the pull-out roller can be set. Can be changed in multiple stages. In addition, an encoder or the like is attached to a rotating portion of the support arm or the like on which the pull-out roller is provided, and the amount of movement of the pull-out roller is detected based on the rotation amount. It is possible to arbitrarily set the drawing length of the film.

In the above embodiment, the case where the unloading direction of the packaged object is the same as the film unloading direction of the drawer has been described. However, even if the unloading direction is opposite to the film unloading direction, the film unwinding of the present invention can be performed. A device can be employed. In this case, the longest movement amount of the drawer body is set in the same manner as in the embodiment, for example, corresponding to a medium-sized packaged object, and a drawer roller is used in combination with a larger-sized packaged object. Thus, the longest movement amount of the drawer can be shortened. Further, in the embodiment, only the length in the film drawing direction is targeted as the size of the packaged object, but the stretch film may be drawn out in consideration of the height dimension of the packaged object. For example, the height of the object to be packaged is measured by a sensor or the like, and the sum of the length twice the height and the length in the film drawing direction may be treated as the size of the object to be packaged.

[0038]

As described above, according to the film pulling-out device of the stretch film packaging machine according to the present invention, regardless of the size of the article to be packaged, it is folded under the article to be packaged. Since the overlapping portions of the film extension portions before and after the film extension can be sufficiently secured, and the film extension portion folded downward does not protrude outward, a good packaging state can always be obtained. In addition, since it is possible to cope with a large-sized packaged object by pulling out the stretch film excessively by the film withdrawing assisting means, the separation distance between the end of the packaged material unloading side and the cutting position of the film by the cutter is required. ,
For example, it can be set according to a medium-sized package, and there is an advantage that the apparatus can be made compact. Further, it is possible to set the amount of movement of the drawer to be short, so that the size of the apparatus can be reduced.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a stretch film packaging machine employing a film unwinder according to an embodiment of the present invention.

FIG. 2 is a plan view illustrating a schematic configuration of a stretch film packaging machine according to an example.

FIG. 3 is a schematic configuration diagram illustrating a main part of the stretch film packaging machine according to the embodiment in a state where a draw-out roller is not operated.

FIG. 4 is a schematic configuration diagram illustrating a main part of the stretch film packaging machine according to the example in a state where a draw-out roller is operated.

FIG. 5 is an explanatory diagram in the case of packing small-sized items to be packaged by the stretch film packaging machine according to the embodiment.

FIG. 6 is an explanatory diagram in the case of packaging small-sized items to be packaged by the stretch film packaging machine according to the embodiment.

FIG. 7 is an explanatory diagram in the case of packaging small-sized items to be packaged by the stretch film packaging machine according to the embodiment.

FIG. 8 is an explanatory diagram in the case of packing a large-sized packaged object by the stretch film packaging machine according to the embodiment.

FIG. 9 is an explanatory diagram in the case of packaging a large-sized packaged object by the stretch film packaging machine according to the embodiment.

FIG. 10 is an explanatory diagram in the case of packaging a large-sized packaged object by the stretch film packaging machine according to the embodiment.

FIG. 11 is a schematic configuration diagram of a stretch film packaging machine according to a conventional technique.

FIG. 12 is an explanatory view showing a large-sized packaged object and a small-sized packaged object packaged by a stretch film packaging machine according to a conventional technique.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Raw material roll (supply source) 12 Stretch film 12a Rear extension part (film extension part) 12b Front extension part (film extension part) 18 Clamping mechanism (clamping means) 20 Pulling body (pulling means) 22 Coated Package 24 Cutter 30 Article receiving stand (pulling-up means) 62 Pull-out roller (film drawing assisting means) 78 Rear folding member (folding means) 80 Left and right side folding members (folding means) 82 Front folding member (folding means) E ₁ Unloading end E ₂ Film cutting position L Separation distance

Claims (3)

[Claims] 1. A stretch film (12) pulled out from a supply source (10) is pinched and moved by an amount corresponding to the size of an article to be packaged (22) to a stretch position.
Drawer means (20) for pulling out (12) substantially horizontally, and the drawer means
(20) a holding means (18) for holding the vicinity of the drawing direction rear end of the stretched film (12) drawn out by the (20), and disposed in the drawing direction rear side from the disposition position of the holding means (18); A cutter (24) for cutting the stretch film (12), and a stretch film disposed below the packaging position and stretched and held by the pull-out means (20) and the holding means (18)
Pushing means (30) for pushing up the packaged item (22) toward (12)
Folding means (78, 80, 82) for folding the film extending portion (12a, 12b) extending outward from the periphery of the packaged object (22) below the packaged item (22). A stretch film packaging machine comprising: a stretch film between the cutting position (E ₂ ) of the stretch film (12) by the cutter (24) and the holding means (18).
A drawer assisting means (62) movable in a direction crossing the drawer path of (12) is provided, and after the stretch film (12) is drawn by the drawer (20), the drawer assisting means (62) is moved. The stretch film (12) is further pulled out from the supply source (10) by causing the stretch film (12) for the packaged object (22).
A film drawing device in a stretch film packaging machine, characterized in that the length of the film extending portion facing the rear side in the film drawing direction after cutting the film is variable. 2. A film extending portion (1) extending outward from a peripheral edge of the packaged object (22) on a rear side in a film withdrawing direction.
2a) and after folding the film extending portion extending outward from the left and right peripheral edges to the lower side of the packaged object (22), the packaged object (22) is drawn in the same direction as the film withdrawing direction. In the process of unloading, the film extension (12b) extending outward from the peripheral edge of the package (22) in the film withdrawing direction front side is moved to the package (22).
2. The film unwinding device in a stretch film packaging machine according to claim 1, wherein the film unwinding device is configured to be folded under. 3. An end (E ₁ ) on the carry-out side of the article to be packaged (22) pushed up by said pushing means (30), and said cutter (24).
Film cutting position by (E ₂₎ and the distance (L) is a film drawing device in stretch film packaging machine according to claim 2, wherein are set to be constant.