JPS6139204B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a packaging machine that uses a stretch film that improves air permeability by being stretched.

If two or more fruits and vegetables, for example, are to be packaged, they tend to scatter, so it is preferable to package them in advance by placing them in a plastic tray.
Furthermore, if even a single item to be packaged has an unstable shape, packaging errors can be reduced by placing it in a plastic tray. However, the blind use of plastic trays is problematic due to waste pollution caused by excessive packaging, and for this reason, in recent years, guidelines have been put in place to prevent the use of plastic trays for anything other than fresh food. It is. However, as explained earlier, in packaging that does not use a tray, the items to be packaged tend to scatter or move during packaging, which inevitably requires a large amount of packaging space. Packaging can only be done in such a way that a space is formed so that the items to be packaged can play within the bag. However, there is no value in using stretch film unless packaging machines that use stretch film forcibly stretch the film to form countless small ventilation holes before wrapping the packaged items. do not have. In this respect, when the object to be packaged is placed in a tray, the stretch film can be stretched and wrapped.

In view of the above-mentioned circumstances, the present invention attempts to tension-wrap an item to be packaged with a stretch film without using a tray.In order to do so, first, a number of independent recesses are formed in the stretched stretch film. , it is necessary to support the object to be packaged within each of these depressions.

Conventionally, a relatively thick film made of thermoplastic synthetic resin is heated and sucked into the recess of a mold by vacuum action to deform the film into a dish shape.
A device is provided for wrapping items in this tray, but even if thin stretch film is used in such conventional packaging machines, the film will melt and it will not be possible to do so. In addition, such conventional types require a film heating device, a vacuum forming mold, and a vacuum machine, which are expensive and also have the drawback of generating a lot of noise when the vacuum machine operates. .

An object of the present invention is to provide a simple mechanism for softening the film into a dish shape without using a heating device or a vacuum forming mold, and to continuously form a large number of independent depressions in the film for packaging objects. The present invention provides a packaging machine that can form

In order to achieve the above object, the present invention provides a pair of endless chains equipped with a large number of clips for holding both side edges of a strip-shaped stretch film and conveying the film horizontally and in its longitudinal direction. A film side supporting and transporting mechanism configured by supporting an appropriate number of chain foils so that most of the space between the two chains is held substantially parallel and the outlet width is smaller than the inlet width of both chains; and the film side supporting and transporting mechanism. a horizontal part that rotates at the same speed and in the same direction as the film side support and conveyance mechanism between the film side and has a pitched slope of a predetermined length at the front end and is continuous with the slope and has the same height as the horizontal part of the film; A pair of endless rotating bodies supported by an appropriate number of chain foils so as to form a chain, a number of partition walls installed between the two rotating bodies at equal intervals and protruding in the circumferential direction, and one end of the endless rotating bodies. a pair of elongated side walls fixed to the upper fuselage and disposed along both sides of each of the partition walls, the lower edges of which are positioned at approximately the same height as the horizontal portion of the endless rotating body; a pair of circular aperture guides for forming tubes by overlapping both side edges of the film so as to cover the object to be packaged supplied onto the film at the upper rear end of the rotating body; The present invention is constructed by providing a heating plate and a sealing stand for welding the stretched stretch film by pressing and heating it from above and below at the same cycle as the feeding interval of the front and rear partition walls.

In the above invention, the upper surfaces of both sides of the stretch film, which is carried while being held by the film side support carrying mechanism, are pressed by the lower surfaces of both side walls, and
Since the stretch film between the two side walls is pushed up from below by a partition wall provided on an endless rotating body, equidistant peaks are formed in the stretch film by the push up action of each partition wall, and each of these peaks is A series of depressions are formed surrounded by walls and both side walls. When the object to be wrapped is supplied to each of the recesses, the end of the film side support mechanism approaches and gradually turns the film into a cylinder, so that the object to be wrapped is placed in the tube of the film while being partitioned by each mountain. The tube is then welded at each peak using a sealing stand and a hot plate to seal each packaged item.

Embodiments of the present invention will be described below with reference to FIGS. 1 to 6.

The packaging machine shown in FIGS. 1 and 2 includes an isolation conveyor A in which an endless rotating body 2 has a large number of partition walls 1, 1, . . . , and a belt conveyor B provided along the isolation conveyor A. , a pair of side walls C, C disposed on both sides of each partition wall 1, 1... on the upper surface of the isolation conveyor A, and a large number of clips 5, 5... on both sides of the isolation conveyor A, respectively. Endless chain 6,6
It consists of a pair of film side support conveyance mechanisms D, D which are formed to lean against each other, and a welding mechanism E provided at the rear end of the separation conveyor A.

Each of the partition walls 1, 1, . chain 2a, 2a
As shown in FIG. 1, the front end portion 3a of the upper surface of the isolation conveyor A is inclined in an ascending slope, and the middle portion 3b is horizontal. The rear end portion 3C is inclined downward. Further, the belt conveyor B described above carries the endless belt 4 through pulleys 4a, 4a.
As shown in FIGS. 4 and 6, between the chains 2a and 2a, the
is attached to the lower surface of each partition wall 1, 1... to constitute a deck plate that fills the hole between each partition wall 1, 1....

On the other hand, one end of each of the side walls C, C is fixed to the frame 7 of the packaging machine, as shown in FIG. 1, and the other end is positioned in an open state in front of the welding mechanism E. As shown in FIGS. 4 and 6, the lower surfaces 8, 8 of these side walls C, C are arranged at a lower position than the upper surface 1b of the partition wall 1, and in order to reduce the friction with the film F on the same lower surface. The rotors 9, 9 are provided at the rotors 9, 9.

Further, the middle portion 3 of the upper surface of the endless rotating body 2
The film side support and conveyance mechanisms D and D are provided at the same height as b. As mentioned above, this mechanism fixes a large number of clips 5, 5, .
6, the intermediate width Y is larger than the entrance width X between these two chains 6, 6, and the rear end portion 3C of the endless rotating body 2
Chain foils 14, 14 for supporting the rear ends of the chains 6, 6 are disposed close to each other at the upper portions of the chains 6, 6. Further, as shown in FIG. 5, the chain foils 14, 1
Disk-shaped aperture guides 17, 17 are coaxially fixed to the lower sides of the chain wheels 4, respectively, and cams 18, 1 are fixed to the upper parts of the chain wheels 14, 14, respectively.
8 are installed.

On the other hand, the welding mechanism E shown in FIG.
9 and an upper hot plate 20 located above it, and these hot plates 19 and 20 are structured to move along oval grooved cams 21 and 21, respectively. Note that the purpose of the invention can be achieved even if the stretch film is fed intermittently at the same pitch as the spacing between the front and rear partition walls 28, 28. The seal table 19 has a structure that presses and heats the film by coming into contact with and separating it at the same position, and in the case where the film runs continuously, the heating plate 20 and the seal table 19 are connected to each other at the same position.
and are driven along the oval grooved cams 21, 21, or a structure as shown in FIG. 8 is used, as will be described in detail later. Each of these sealing devices is known to those skilled in the art.

The present invention is constructed as described above, and its operation will be explained below.

In FIG. 1, a stretch film F (hereinafter referred to as film F) supported in the form of a roll on a shaft 23 in the upper front end area of the isolation conveyor A is unwound by a pair of feed rolls 24 and 25, and then The film is supplied between the film side support and transport mechanisms D and D at a constant speed.

Therefore, the clips 5, 5 in both film side support and conveyance mechanisms D, D... pinch both side edges of the film F, and begin conveying the film F in the direction of rotation of the chain wheels 14, 14. Fifth
In the figure, the spring 2 is moved by the cams 18, 18 at the rear end of the film side support and conveyance mechanism D, D.
6 and 26 are compressed and the clips 5 and 5 open both side edges of the film F. Based on a principle symmetrical to this, at the entrance of the film side support and conveyance mechanisms D and , it is easy to automatically catch both side edges of the film F with the clips 5, 5. Since both film side support and conveyance mechanisms D, D have an intermediate width Y larger than an entrance width X, the film F is simultaneously stretched in both directions while being conveyed by the chains 6, 6.

On the other hand, the isolation conveyor A and the belt conveyor B are set in advance to rotate at the same speed and in the same direction as the film F, and as a result, each of the partition walls 1, 1 provided on the endless rotating body 2 ... pushes up the film F one after another at the uphill slope portion of the front end portion 3a as shown in FIG. Since this type of stretch film F made of butadiene rubber or the like has excellent stretchability, each of the partition walls 1, 1...
It will not be torn by pushing up. As shown in FIG. 6, the film F has already been stretched in the direction of the arrow, that is, in both directions, by the film side support and conveyance mechanism, and in this state, the partition walls 1, 1, . . . push up. Film F
In this case, the partition wall 1 locally swells like a mountain. The so-called film F has many mountains 28, 28
... are formed at equal intervals, and each of these peaks 28, 28...
A valley is formed in between, and both sides of this valley are side walls C and C.
A depression is formed in a portion surrounded by the front and rear mountains 28, 28 and both side walls C, C. In this case, since the film F is pulled in both directions by the clip, each peak 28 formed on the film forms a long ridge like a base that is particularly long in both directions. The lower surfaces 8, 8 of the side walls C, C approach the partition wall 1 and press down on the ridges of the film F, so that a deep depression can be formed between the front and rear ridges.

Therefore, as shown in FIG. 1, when the object to be packaged Z is fed into the recess formed in the film F as described above, each of the objects to be packaged before and after each of the partition walls 1, 1
... and transported on film F in an isolated state. At the rear end portion 3C of the isolation conveyor A, the film side supporting and conveying devices D and D approach each other, so that both edges of the film F overlap the top of the packaged object Z as shown in FIG. Since both side edges are pressed between the pair of left and right aperture guides 17, 17, the film F is formed into a tube.
Furthermore, the upper and lower hot plates 20 and 19, which perform an elliptical motion along the grooved cams 21 and 21, are connected to the front and rear bars 1.
As a result of sandwiching and welding the film between a and 1a,
Each packaged item is sealed in a bag _F1 formed by film.

In addition, FIG. 7 shows the part where the film F is formed into a tube shape, and a pair of belts 3 are attached inside the film.
0 and 30 are supported by pulleys 31, 31, 32, and 32 and arranged in a V shape to prevent the both side edges of the film F, which has been stretched once, from suddenly shrinking due to friction between the belts 30, 30 and the film F. This is an example. FIG. 8 also shows that each partition wall 33 of the isolation conveyor A is used as a base on one side of the welding mechanism, and the partition wall 33 and the rotor 3
This is an embodiment in which the film F is welded with the heating wire 35 provided at 4.

As described above, the present invention includes a pair of film side support and conveyance mechanisms that hold both side edges of a strip-shaped stretch film and convey the film horizontally and while stretching the film in both directions; an isolation conveyor that is located between the conveying mechanisms and gradually pushes up the stretch film using partition walls provided at equal intervals on an endless rotating body, and then horizontally moves within a predetermined range while keeping the film pushed up through these partition walls; There are side walls on both sides of the partition wall that press down the hem of the mountain formed on the film by the pushing up of these partition walls. A recess can be formed in the stretched film, and by supplying the object to be wrapped into this recess, the end of the film side support mechanism approaches the object to be wrapped, and the stretched film covers the object in a cylindrical shape. While the film is tensioned by a pair of circular aperture guides, the front and rear peaks separating the packaged items can be sealed one after another by a sealing stand and a hot plate.
In this way, it is possible to use the stretchability of stretch film to form something similar to a container and package the object, so it can be used in conventional machines that use vacuum suction to form containers and wrap them. In comparison, it is economical as it does not require heating equipment or vacuum forming power equipment to soften the film, and it is also more effective than tray packaging machines in that it can perform tension packaging without scattering the packaged items. be.

[Brief explanation of the drawing]

Figure 1 is a side view of the present invention, Figure 2 is a plan view of the previous figure, Figure 3 is a perspective view of Figure 1, and Figure 4 is a side view of the present invention.
5 is a sectional view taken along line 2 in FIG. 2, FIG. 6 is a partial perspective view, and FIGS. 7 and 8 are explanatory views of other embodiments. A... Isolation conveyor, C... Side wall, D... Film side support conveyance mechanism, E... E... Welding mechanism, F... Film, 1... Partition wall, 2... Endless rotating body, 3a... ...Front end part, 3b...Middle part, 3c...Rear end part, 5...Clip, 17
...Aperture guide, 18...Cam, X...Entrance width,
Y……Middle width.

Claims (1)

[Claims] 1. A pair of endless chains equipped with a number of clips for holding both side edges of a strip-shaped stretch film and conveying the film horizontally and in the longitudinal direction are installed with most of the space between the two chains substantially parallel to each other. a film side supporting and transporting mechanism configured by supporting an appropriate number of chain foils so that the chain has an outlet width smaller than the inlet width of the chain; It is a film that rotates in the direction of the film, and has a pitched slope of a predetermined length at the front end, and is supported by an appropriate number of chain foils so as to form a horizontal part continuous with the slope and having the same height as the horizontal part of the film. A pair of endless rotating bodies arranged at a pair of elongated side walls arranged along the same axis and having their lower edges positioned at approximately the same height as the horizontal portion of the endless rotating body; A pair of circular aperture guides in which both side edges of the film are overlapped to form a tube so as to cover the object to be packaged, and the tube-shaped stretch film is placed behind the aperture guide between the front and rear partition walls. A packaging machine equipped with a hot plate and a sealing stand for welding the film by clamping and heating it from above and below at the same cycle as the feed interval.