JPH09183408A - Stretchable film packaging machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a film from being damaged and retain a folding margin even if a fold initially performed is deep by performing an initial fold only at a center of an object to be packaged mounted on a packaging part or only the center and an end by a folding roller. SOLUTION: An object H to be packaged which has been carried to immediately below a packaging part D is projected vertically toward a film 30 extended at a predetermined position of the packaging part D by a conveyer table 20. Left and right folds 41a, 41b move to the center approximately simultaneously as release of left and right clamps 43a, 43b and stop with a slight distance between them at a bottom center of the object H. Approximately simultaneously as this, front and rear fold plates 40a, 40b start moving toward the center. Further, following this, front and rear grippers 32, 33 come close to each other, and film contact faces of the front and rear fold plates 40a, 40b come into contact with each other, thereby completing folding. The object H is taken out from the packaging part D, and folding margins 52, 53 are heat-sealed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stretch film packaging machine, and more particularly to a technique for folding a film.

[0002]

2. Description of the Related Art Conventionally, in the folding of a film in a stretch film packaging machine of this type, the lateral direction is first folded with respect to the traveling direction of the article to be packaged.

However, if a horizontally long product such as Chinese cabbage is completely wrapped up to the center so that the leaves do not fall off, the folding amount of the film becomes long, so that the film of the folding plate The film often broke due to the frictional resistance with the contact side. Further, if the first folding is performed deeply, there is a problem that the folding margin at the time of the next folding in the front-rear direction is reduced and the sealing of the film becomes incomplete. The present invention has been made to solve the above problems, and even if the folding of the film to be performed first becomes deep, it is possible to secure the sufficient folding margin for the next folding without damaging the film. It is an object of the present invention to provide a stretch film wrapping machine that can perform.

[0003]

[Means for Solving the Problems] The technical means taken to solve the above-mentioned problem is, in claim 1, that the object to be packaged is pushed up toward the stretched film and the end portion of the film is packaged. In a stretch film wrapping machine that folds in the front-back direction and the left-right direction under the item, the first folding is
It is characterized in that it is performed by a roller that folds only the central portion of the article to be packaged placed in the packaging portion or only the central portion and one end portion. Here, the folding that is performed first is, for example, the folding that is performed first when the packaging object is folded in two directions, ie, the front-rear direction and the left-right direction.
Further, the central portion and one end portion of the packaged object are the portions when the sides of the packaged article to be folded are divided into three parts, the central portion and both end portions. The roller support structure may be a flat plate member or a frame member.

According to the second aspect of the present invention, a stretch film package in which the object to be packaged is pushed up toward the stretched film and the ends of the film are folded under the object to be packaged in the front-rear direction and the left-right direction. In the machine, the first folding is the film contact side of the portion where the folding is performed deeply in the folding plate of the shape where the folding is performed shallowly from the center to the end of the packaged object placed in the packaging section. It is characterized in that it is performed by a folding member provided with a roller for folding only the central portion or only the central portion and one end portion. Here, the shape of performing the shallow folding from the central portion to the end means that when the film is folded under the object to be packaged, the film in contact with the central portion of the folding plate is the central portion of the object to be packaged. It is a shape in which the film is folded up to the vicinity, and the film is folded up to the position away from the center of the packaged object toward the end.

According to the third aspect of the invention, a notch into which a part of the roller is inserted over the length of the roller is formed in the film contact side of the portion where the folding plate is deeply folded. It is characterized by being provided. Here, the part of the roller entering means a depth of the notch in which the tip of the roller does not enter the inside of the film contact side.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows the appearance of the stretch film packaging machine of the present invention. This stretch film wrapping machine comprises a carry-in section A, a transport section B, a film pull-out section C, a wrapping section D, a take-out section E, a heater F, and a control section G on the front surface of the apparatus.

FIG. 2 shows a cross section of the stretch film packaging machine. The carry-in section A is composed of a weighing section 10 and an article mounting table 11 connected to the weighing section 10. The transfer section B includes a transfer table 20, a horizontal operation section 21 and a vertical operation section 2 of the transfer table.
2 and is capable of horizontal movement from the object mounting table to directly below the packaging unit D and vertical movement to a predetermined position of the packaging unit.

FIG. 3 is a perspective view showing the structure of the film pull-out portion C. The film pull-out part C is a film 3
A film roll 31 which is wound around 0, a front gripper mechanism 32 which holds the leading end of the film and pulls it horizontally to a predetermined position of the packaging section D and at the same time holds it in a tensioned state.
A rear gripper mechanism 33 that holds the rear end of the film and holds the tensioned state, and the gripper drive unit 3 before and after these
4 and a cutter 35 for cutting the film.

FIG. 4 is a perspective view showing the structure of the packaging section D. The packaging unit D includes front and rear folding plates 40a and 40b, left and right folding plates 41a and 41b, and a folding plate driving unit 4.
2, and further comprises left and right clamp mechanisms 43a and 43b. The front and rear folding plates are a drive chain 45 arranged on both sides so that a pair of flat plates extending in the width direction of the apparatus main body can be horizontally moved back and forth from the front gripper mechanism side and the rear gripper mechanism side respectively. It is configured such that the leading end 36 and the trailing end 37 of the film 30 are simultaneously folded into the bottom portion of the article H to be packaged by approaching each other at the same speed. On the other hand, the left and right folding plates have their rear ends connected to a drive chain 44 provided on the rear gripper side so that a pair of flat plates extending in the length direction of the apparatus main body can be horizontally moved to the left and right sides, and at the same speed as each other. The left and right edges of the film are arranged so as to approach each other and to be simultaneously folded into the bottom of the package.

FIG. 5 is a plan view of the left and right folding plates. FIG.
(A) and (b) are the AA sectional drawing and BB sectional drawing in FIG. The film contact side 45 has a substantially trapezoidal shape in which the central portion thereof projects toward the center of the packaging portion when viewed in a plan view, and the projection is reduced as it approaches both ends. And
A roller 48 having a diameter slightly larger than the plate thickness of the left and right folding plates is rotatably supported inside a notch 47 provided in a portion where the film contact side 46 is deeply folded. At this time, the outer peripheral surface 49 of the roller is made to project slightly outward from the film contact side 46 so that the roller outer peripheral surface 49 directly contacts the film 30, and both ends of the roller are mainly subjected to front and rear folding performed later. The film 30 is prevented from being caught by the portion 51 and being damaged. For the same reason, both end portions 51 of the roller are formed in an R shape and chamfered. Furthermore,
By making the cross-sectional shape of the film contact side 46 a semicircle,
The protrusion amount of the roller 48 becomes uniform, and the film 30
It reduces the catch of.

Next, the process of the packaging section in the stretch film packaging machine of the present invention will be described. (1) The article to be packaged H is transported to just below the packaging section D by the transport table 20, and in parallel with this, the film 30 is pulled out to a predetermined position in the film pulling-out section C. (2) Then, the film 30 has front and rear grippers 32,
33 and the left and right clamps 43a and 43b. (3) Next, the article to be packaged H that has been transported to just below the packaging section D
Is vertically pushed up toward the film 30 stretched at a predetermined position of the packaging section D by the carrier 20. (4) The left and right folding plates 41a and 41b move to the center substantially at the same time as the release of the left and right clamps 43a and 43b, and stop with a slight gap between them at the center of the bottom surface of the article H to be packaged. FIG. 7 is a plan view showing the state at this time, and the front and rear folding margins 52 and 53 are sufficiently secured despite the deep left and right folding. (5) Almost at the same time, the front and rear folding plates 40a, 40
b starts moving in the center direction, and the front and rear grippers 32, 33 move in a direction in which they approach each other in a form of further tracking. (6) The film contact surfaces of the front and rear folding plates 40a and 40b abut against each other to complete the folding. (7) The article to be packaged H is taken out from the packaging section D, and the folding margins 52 and 53 are pressed against the heater F to heat-seal the bottom of the article to be packaged H. FIG. 8 is a diagram showing a state of the bottom surface of the packaged item at this time. Left and right folding allowances 54,5
Heat sealing is performed in a state in which the front and rear folding margins of 5 are completely covered.

In the above embodiment, the left and right folding plates are provided so that the folding at both ends can be performed shallowly. However, the shape of the left and right folding plates is not limited to this and is shown in FIG. Such one end may be shallowly folded. In this case, one of the front and rear folding margins is shallowly folded, but the other folding margin can be sufficiently secured, so that if this is placed outside, sufficient heat sealing can be performed.

Also, the description has been given of the packaging machine in which the operator manually takes out the packaged goods after the folding is completed and presses the bottom portion against the heater, but the folding machine leaves only one side and the remaining side is simultaneously discharged. The present invention can be applied even to a packaging machine that automatically discharges and heat seals a packaged object, such as a folding machine.

[0014]

The stretch film packaging machine according to the present invention has the following effects due to the construction described in claim 1. The folding that is performed first is performed by a roller that folds only the central portion of the article to be packaged placed in the packaging portion, or only the central portion and one end portion, so that the frictional resistance applied to the film during folding is reduced. Therefore, even if the amount of folding is large, it does not tear the film,
It can be easily packaged even if it is horizontally long like Chinese cabbage and it is necessary to completely fold the film to the center so that the leaves do not fall off. In addition, one end in the direction of folding first,
Since it is not folded by the roller, the width of the folding margin of the next folding is not narrowed, and the packaging can be surely performed.

Further, according to the second aspect of the invention, the roller is provided at the film contact side of the portion where the folding is performed deeply in the folding plate having a shape in which the folding is performed from the central portion toward the end portion. Even if the rollers involved in the actual folding are small, the article to be packaged can be placed on the folding plate. Therefore, at the time of the next folding, the article to be packaged can be surely folded without wobbling. Further, since there is a folding plate behind the roller, the risk of winding the film around the roller is reduced.

Further, according to the structure described in claim 3, a notch into which a part of the roller is inserted over the length of the roller is formed in the film contact side of the portion where the folding plate is deeply folded. Since it is provided, the risk of the film being caught by the roller in the next folding step is reduced.

[Brief description of the drawings]

FIG. 1 is an external view of a stretch film packaging machine.

FIG. 2 is a cross-sectional view of a stretch film packaging machine.

FIG. 3 is a perspective view showing a structure of a film pull-out portion.

FIG. 4 is a perspective view showing a structure of a packaging unit.

FIG. 5 is a plan view of the left and right folding plates.

FIG. 6 is a cross-sectional view of left and right folding plates.

FIG. 7 is a plan view showing a state in which left and right folding is completed.

FIG. 8 is a bottom view of the packaged object that has been packaged.

FIG. 9 is a plan view showing another modification of the left and right folding plates.

FIG. 10 is a plan view showing another modified example of the roller supporting method.

[Explanation of symbols]

 A ... Carrying-in section B ... Conveying section C ... Film drawing section D ... Packaging section E ... Extracting section F ... Heater G ... Control section H ... Packaged object

Claims (3)

[Claims] 1. A stretch film wrapping machine that pushes up an object to be packaged toward a stretched film and folds the end of the film under the object to be wrapped in the front-rear direction and the left-right direction. A stretch film wrapping machine, characterized in that it is carried out by a roller that folds only the central part of the article to be packaged placed on the section, or only the central part and one end. 2. A stretch film wrapping machine in which a packaged object is pushed up toward a stretched film and the end portions of the film are folded under the packaged object from the front-rear direction and the left-right direction, the first folding is performed at the center. Part to the end, the film contact side of the part where the folding is performed deeply in the folding plate of the shape that is shallowly folded, only the central part of the packaged object placed in the packaging part, or the central part and one end part A stretch film wrapping machine characterized in that it is carried out by a folding member provided with a roller for folding only. 3. The film contact side of a portion of the folding plate where the folding is performed deeply, over the length of the roller,
The stretch film wrapping machine according to claim 2, wherein a cutout into which a part of the roller is inserted is provided.