JP3473426B2 - Stretch wrapping machine - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a stretch wrapping machine,
More specifically, the present invention relates to a stretch wrapping machine used in the backyard of a supermarket or the like for wrapping products such as fresh foods using a stretch film.

[0002]

2. Description of the Related Art Conventionally, in this type of stretch wrapping machine, the film pulled out from a film roll is conveyed and stretched by a film conveying mechanism to the wrapping section, while meat, sashimi, fish, etc. are loaded on a tray. It is carried into the packaging machine by the mechanism, the tray is pushed up toward the film by the elevator, the upper surface and the side surface of the tray are covered with the film, and further the end of the film is folded into the bottom surface of the tray and then heat sealed to complete the packaging. It is a thing. However, when the tray upper surface has a glossy surface, the tray upper surface may adhere to the film when the tray is pushed up, and in that case, the film supplied to the packaging unit is wrinkled during its transportation. When the film is stretched in the state where the film is stretched, the film surrounded by the four sides on the top of the tray will not be stretched even if the tray is further pushed up and will be wrapped with wrinkles remaining, resulting in a poor packaging finish. Not preferable.

Therefore, in the conventional packaging machine, before the tray (product) is pushed up, a pre-stretching operation for stretching the stretched film by a predetermined amount in the width direction is performed to remove the wrinkle even if it occurs. I am trying. However, in order to perform the pre-stretching operation, a mechanism for widening the gap between the film clamps (conveying belts) on both sides of the film conveying mechanism is required, and the structure including the mechanism and the driving unit becomes large and expensive. There is a problem that becomes. Further, a method of arranging the above-mentioned two-sided conveyor belts in a divergent shape to perform a pre-stretching operation is also adopted, but this method is not preferable because a positional deviation may occur when the film is transferred from the film roll to the conveyor belt. At the same time, there is a problem that a sufficient amount of pre-stretch cannot be secured.

Further, conventionally, there is known a stretch wrapping machine in which a clamp plate for clamping both side edges of the film and a film extending member which moves up and down are arranged in common with a driving source (see Japanese Utility Model Laid-Open No. 5-82804). . Although this conventional wrapping machine has the advantage of being simple and inexpensive, the method of the film transport mechanism is a method of gripping the leading edge of the film from the film supply section and pulling it out and transporting it. This is a possible structure because the end portions are clamped, and it is a configuration that cannot be adopted in a system in which both side end portions of the film are conveyed while being sandwiched by a conveyance belt. That is, in the method of transporting the film by the transport belt, there is a problem that the film is caught on the film extending member during transport of the film.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional circumstances, and provides a stretch wrapping machine which has a simple and inexpensive structure to perform a pre-stretching operation to remove wrinkles from a film, and which has a good packaging finish. The purpose is to provide.

[0006]

According to the stretch wrapping machine of the present invention, a film transport mechanism having a transport belt clamps both side edges of the film and transports the film to supply it to the wrapping section. In a stretch wrapping machine that pushes up and wraps a product toward the film, a wrinkle removing member that pushes up the inside of the supplied film along the conveyor belt to a predetermined height from below and extends the wrapping portion can be moved up and down. It is characterized by being provided. The wrinkle removing member is in a standby state until the film is fed to the packaging section by the film transport mechanism, and the upper surface position of the wrinkle removing member in the standby state is slightly lower than the film transport surface so as not to hinder the film supply. After the film is supplied to the wrapping unit, the film is lifted up a predetermined time, and the upper surface position at the time of lifting is set higher than the film transport surface, but much lower than the uppermost position for pushing up the product.
By the rise of the wrinkle removing member, the wrinkles are removed even if the film is pre-stretched by the amount of the rise of the member and wrinkles are generated in the film.

The above-mentioned film transport mechanism has a transport belt for sandwiching the upper surface and / or the lower surface of the film on each side. However, it is not always necessary that the transport belt has a pair of upper and lower sides, and one of them is a slippery pad. It is also possible to use, and it is preferable to dispose a film clamp on the transport belt in order to increase the film clamping force.
That is, as a mode of the film transport mechanism, preferably, each side is configured by a pair of a transport belt and a film clamp that comes into contact with and separates from the belt, and a transport belt or a contact plate that faces the transport belt (claim 2). .

The wrinkle removing member may be arranged on each inner side of the both-side conveying belt of the film supplied to the wrapping portion, but in order to secure a predetermined amount of pre-stretch, one side of the film is secured. It is preferable to dispose only on the part (claim 3). Then, when the wrinkle removing member is provided only on one side, it may be arranged on either side facing each other, but the stretching is such that the packaging machine folds the last film end portion while discharging the product from the packaging portion. In the case of a packaging machine, it is not necessary to provide it in a narrow flat space between the folding rod after the last folding and the product immediately before folding, and in consideration of the arrangement space, it is arranged on one side opposite to the product discharge side. It is preferable to do so (claim 4).

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described with reference to the drawings. FIG. 1 and FIG. 2 schematically show a stretch wrapping machine. In the figure, in front of the machine frame A, a placing section a for placing a tray B containing products such as meat and sashimi is provided, and the tray placed on the product placing section a is moved by the pusher conveyer 1 to the machine frame. It is conveyed to the elevator 2 provided inside A. The product placing portion a is configured as a weighing pan of the weighing mechanism. A wrapping part b is provided above the elevator 2, and a film roll arranging part 3 and a film roll set in the film roll arranging part 3 are provided on the side of the wrapping part b (the direction intersecting the pusher conveyor at a right angle). 4 is provided with a film holding unit 5 for holding the leading end of the film 4 ′ fed out from the film 4 ′, and a film transport mechanism 6 for holding the leading end of the film 4 ′ held by the film holding unit 5 and transferring it to the drawer packaging unit b. It is arranged close to the tip of the film holder 5.

Further, between the film holding section 5 and the film transport mechanism 6, a cutter 7 for cutting the film 4'nipped and pulled out by the film transport mechanism 6 into a predetermined length.
Are arranged. Further, above the film transport mechanism 6, the left and right folding plates 8 and 8'for folding the end portion of the film 4'covering the upper surface of the tray B to the bottom side of the tray B, the rear folding plate 9, and the rear folding plate 9 are provided. A discharge pusher 10 for discharging the packaged tray B is provided at the position.

The film holding unit 5 holds the leading end of the film 4'of the film roll 4 set in the film roll arranging unit 3, and is located below the film as shown in FIG. A film receiving plate 12 'which is erected and fixed over the endless belt 12 arranged in parallel at a predetermined interval, and a film supported on the surface of the film receiving plate 12' by the film receiving plate 12 '. The holding plate 13 has the same shape and holds it, and the holding roller 14 attached to the film receiving plate 12 '. Holding plate 13 is machine frame A
Film support plate 12 'supported so that it can slide vertically with respect to
The film support plate 1 is rotatably supported by
Attach to 2'and slide up and down together, film receiving plate 12 '
The tip of the film 4'which is held by the holding plate 13 and the holding plate 13 can be delivered to the film transport mechanism 6.
The holding roller 14 has its outer surface fitted and projected into the through hole formed in the holding plate 13 through the through hole formed in the receiving plate 12 ', thereby causing the film 4'to meander along the peripheral surface of the holding roller 14. The film is held securely.
The holding roller 14 is configured to be rotatable only in the film drawing direction.

The endless belt 12 is a stepping motor 17
Is used as a drive source, and the endless belt 12 is driven by the motor 17.
Is configured to move up and down (forward and reverse rotation) along the moving direction of the film, whereby the film receiving plate 12 'and the holding plate 13 are moved up and down together in the moving direction of the film. Also,
The drive of the feeding roller 16 is controlled by a motor (not shown). Then, when the motor 17 moves the film receiving plate 12 ′ and the holding plate 13 upward, the feeding roller 16
When the motor 17 rotates in the reverse direction and the film receiving plate 12 'and the holding plate 13 are returned to the initial positions,
The delivery roller 16 continues to rotate in synchronization with the film transport mechanism 6 to deliver the film.

As shown in FIG. 1, the film transport mechanism 6 is composed of a front belt mechanism 6A and a rear belt mechanism 6B which are arranged in front and back of the packaging portion b, and each belt mechanism 6A,
6B is supported by the mounting frames 18 and 18 '. The front and rear belt mechanisms 6A and 6B respectively have a pair of upper and lower endless elastic belts 20 and 21 that sandwich both side ends of the film in the width direction.
And the clamp plate 22 arranged in the lower elastic belt 21.
And a contact plate 24 disposed inside the upper elastic belt 20 and a transfer belt 24 connected to the film supply side of the upper elastic belt 20 (see FIG. 2). Clamp plate
22 is the upper elastic belt which is the forward side of the upper elastic belt 20.
The contact plate 23 is configured to be capable of being pressed into contact with the outward path of 20 and the pad plate 23 is inserted and arranged between the outward path and the return path of the upper elastic belt 20. In the figure, the clamp plate 22 is illustrated as being divided into five pieces. Further, the starting end side of the lower elastic belt 21 is inclined downward toward the front end side of the film holding portion 5, and the inheritance belt 24 is arranged so as to be superposed on the downwardly inclined starting end side upper surface. The transfer belt 24 is configured such that its tip end side can be opened and closed.

The pair of endless elastic belts 20 and 21 are
It is driven and rotated in the same direction so that the film can be nipped and conveyed, and the driving method uses a stepping motor 25 with a speed reducer, and the lower elastic belt 21 is wound around its drive shaft 26. Power is transmitted by chain-linking the roller 27 and the drive roller 28 around which the upper elastic belt 20 is wound (see FIG. 3).

Next, the film wrinkle removing member 30, which is the main part of the present invention, will be described in detail with reference to FIGS.
The wrinkle removing member 30 is arranged close to the mounting frame 18 'that supports the rear belt mechanism 6B of the film transport mechanism 6 described above. That is, support frames or support rails 31 and 31 for partitioning the wrapping section area are arranged in the wrapping section b at left and right intervals, and the front belt mechanism of the film transport mechanism 6 is provided on the support frames 31 and 31. 6A and rear belt mechanism
Although 6B is supported, the wrinkle removing member 30 is arranged on the mounting frame 18 'on the rear side. A support surface 19 consisting of a vertical wall is integrally or separately provided on the inner surface side of the attachment frame 18 ', and two swinging rods 33, which are pivotally attached to the support surface 19 so that the lower part thereof is rotatable, Parallel link member composed of 33 arranged side by side
32 is attached so that the parallel link member 32 moves up and down along the support surface 19. The wrinkle removing member 30 is a long member that is rotatably attached to the upper ends of the rods 33, 33 of the parallel link member 32 and is horizontally arranged. Further, the wrinkle removing member 30 has an inverted U-shaped cross section to remove the wrinkle. It should be accommodated under the flat space of the member 30.

The swing rods 33, 33 of the parallel link member 32 are
In order not to limit the arrangement position, the extension 33 'is integrally formed at each lower end, that is, the extension 34' of one of the swinging rods 33 is connected to the solenoid 34 serving as the drive source of the link operation. Then, the wrinkle removing member 30 can be moved up and down horizontally by the ON / OFF operation of the solenoid 34. The solenoid 34 is provided on the outer side of the packaging part b as shown in the drawing so as not to interfere with the lifting operation of the elevator 2 during the packaging operation.
Specifically, it is preferable to arrange it on the outer side of the support frame 31. Therefore, the wrinkle removing member 30 is arranged inside the rear belt mechanism 6B of the film transport mechanism 6 and can move up and down. The wrinkle removing member 30 may be made of metal or plastic. The upper surface of the wrinkle removing member 30 has a chamfered shape so as not to damage the film, and the wrinkle removing member 30 has a rough surface so as to have a low friction so as to prevent contact with the four peripheral edges of the tray B. It is preferable to finish the surface.

The wrinkle removing member 30 is in a standby state until the film 4'is conveyed to the packaging portion b, and at the standby position, the upper surface of the member 30 is the film conveying surface, that is, the films of the upper and lower elastic belts 20 and 21. Clamping surface, slightly lower (H: 5 mm
It is set at a position lower than that (see FIG. 6B). When the solenoid 34 is turned on, the wrinkle removing member 30
Although the upper surface of the tray is higher than the film transport surface, the tray B
The position is set to be lower than the push-up position, specifically, to a position (H ') higher than the film transport surface by about 2 to 3 cm (see FIG. 8 (2)).

The wrapping operation of the stretch wrapping machine will be described below. The leading edge of the film 4'from the film roll 4 of the film roll arranging portion 3 is located between the film receiving plate 12 'and the holding plate 13 of the film holding portion 3. With it set to
The packaging work is started based on the predetermined packaging control data. By driving the stepping motor 17 shown in FIG. 1, the endless belt 12 advances toward the transfer belt 24 of the film transfer mechanism 6 to transfer the film 4'to and from the transfer belt 6 ', and at the same time, the film transfer mechanism 6' When the film 4'is pulled out by a predetermined length, the cutter 7 cuts it. The film transport mechanism 6 further transports the cut film 4 ′ and supplies it to the packaging unit b.
After centering, the wrinkle removing member 30 of the present invention operates. The five-divided clamp plate 22 described above may perform a clamp operation in which all the clamp plates 22 are pressed against the elastic belt 21 from the initial stage of the film transport operation.
In this example, the two clamp plates before and after perform the clamping operation from the initial stage of the conveyance, and the three central clamp plates perform the clamping operation immediately after the centering.

In the packaging portion b, the wrinkle removing member 30 stands by at the standby position shown in FIG. 6 described above, and the film 4'conveyed to the packaging portion is not wrinkled as shown in FIG. It may be conveyed and supplied in the generated state.
After the centering of the film, the central three clamp plates 22 clamp both side ends of the film 4 ', and at the same time, the solenoid 34 is turned on, and the parallel link member 32 is turned on.
The wrinkle removing member 30 moves upward by the action of, and pushes up the inner portion of the elastic belt 21 of the rear side belt mechanism 6B of the film 4 ′ by a predetermined height (see FIG. 8). As a result, the film 4'is pre-stretched, and even if wrinkles are formed on the film 4 ', the film 4'is stretched in a tension state in which the wrinkles are removed (see FIG. 9).

On the other hand, the tray B transported onto the elevator 2 is pushed up by the lift of the elevator 2 with respect to the film 4 ′ stretched around the packaging portion b. In the course of the pushing up operation, more specifically, the tray B. When the upper surface of the solenoid is slightly higher than the upper surface of the wrinkle removing member 30, the solenoid
Turn OFF 34 (see Fig. 10). OFF of solenoid 34
By the weight of the wrinkle removing member 30 and the parallel link member 32, the wrinkle removing member 30 is returned to the standby position shown in FIG. 6, while the tray B is further moved up to the upper limit position by the elevator 2 and the film 4 '. It is covered with (see Fig. 11). After that, while releasing the clamp plate 22 in a timely manner,
The end of the film covering the upper surface of the tray B is folded to the bottom side of the tray B by the left and right folding plates 8 and 8'and the front folding plate 9, and then the ejection pusher 10 moves the tray B to the machine frame A.
While horizontally pushing the film 4'to the discharge portion (heat seal portion) 11, the rear end of the film 4'is folded into the bottom surface of the tray B by the rear folding rod 11 'to complete the packaging operation.

According to the embodiment of the present invention described above, the following features are provided in addition to the features described in the claims. (1) A parallel link member 32 configured by arranging two rocking rods 33, 33 side by side in a mechanism for operating the wrinkle removing member 30.
The structure which connected. As a result, it is possible to secure the levelness of the wrinkle removing member 30, which is a long member, at the time of vertical movement, has an excellent wrinkle removing action, and has a smooth vertical movement, and one small solenoid can be used as a drive source. (2) A structure in which the wrinkle removing member 30 has an inverted U-shaped cross section, and the parallel link member 32 is arranged directly below the member 30. As a result, the parallel link member 32 can be stored under the flat space of the wrinkle removing member 30, and the maximum packaging size that does not hinder the elevator 2 from being raised or lowered can be ensured. Further, the solenoid is also arranged outside the packaging portion b, so that the maximum packaging dimension can be secured in the same manner. (3) A structure in which the wrinkle removing member 30, the parallel link member 32, which is the operating member thereof, and the solenoid 34 are arranged in the mounting frame 18 ′ of the rear belt mechanism 6B. As a result, even when the rear belt mechanism 6B is moved together with the mounting frame 18 ′ to change the film width, the wrinkle removing member and the like are automatically moved following the movement. That is, it is possible to easily deal with the change of the film width.

In the above embodiment, the packaging machine has the discharge pusher 10 and the function of automatically discharging the products, but it is needless to say that the packaging machine may not have the function. is there. Further, as the film transport mechanism, the case where the upper and lower elastic belts 20 and 21 are paired has been exemplified, but it is also possible to use the elastic belt for one of the elastic belts and substitute the other slippery contact plate. Further, although the case where the wrinkle removing member 30 is provided only on one side of the film transport mechanism (film) is disclosed, the invention is not limited to this, and the wrinkle removing member 30 may be provided on both sides of the film. Is also possible. In that case, it is preferable that the upper surface of the wrinkle removing member is configured to be sufficiently slippery, for example, to have a freely rotatable roll surface structure. Furthermore, the wrinkle removing member 30
A solenoid was used as the drive source of the
It is also possible to use a motor or an air cylinder, or to transmit from another drive source such as a main motor for driving an elevator, or to use an actuating member instead of the parallel link member.

[0023]

According to the present invention, the film supplied to the wrapping part is moved along the conveyor belt by the rise of the wrinkle removing member.
The inside is higher than the film transport surface, but the product is pushed up
Since the film is pushed up and extended to a height much lower than the uppermost position , the film is pre-stretched by the amount of increase of the wrinkle removing member, and even if the film has wrinkles generated during transportation, the wrinkles are pre-stretched. Are removed by. Therefore,
Even with the film supply system in which both side edges of the film are conveyed while being sandwiched by the film conveyance mechanism, it is possible to provide a stretch wrapping machine having a wrinkle-free wrapping finish with a simple and inexpensive structure. According to the second aspect of the present invention, the film transport mechanism is concretely provided so as to reliably hold the film on the transport belt by the action of the film clamp, and the film transport function is enhanced so that the wrinkle is less likely to occur. It is possible to reduce the burden such as minimizing the vertical stroke of the removing member.

When the wrinkle removing members are arranged on both sides of the film and the both sides are pushed up, the width of the film portion in contact with the upper surface of the wrinkle removing member does not change, so that the amount of pre-stretching is reduced. Although it is unavoidable, according to the third aspect, since the predetermined amount of pre-stretching can be reliably ensured, the effectiveness of wrinkle removal can be enhanced. Further, according to claim 4, the arrangement space of the wrinkle removing member is not limited as compared with the case where the wrinkle removing member is arranged on the product discharge side. Therefore, the upper surface of the wrinkle removing member can be widened, and the film at the time of pushing up the film can be increased. Damage can be prevented.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view showing an outline of a stretch wrapping machine of the present invention.

FIG. 2 is a vertical front view of FIG.

FIG. 3 is an enlarged detailed view of a film transport mechanism including a wrinkle removing member, which is a main part of the present invention, in which (1) is an enlarged front view and (2) is a portion within a circle of (1). FIG.

FIG. 4 is a plan view of FIG. 3 (1).

FIG. 5 is a view showing a state in which a wrinkle removing member is raised.
It is a front view corresponding to (1).

FIG. 6 is an enlarged detailed view of the wrapping portion, in which (1) is a vertical cross-sectional side view showing a standby state of the wrinkle removing member, and (2) is an enlarged view of a circled portion in (1).

FIG. 7 is a perspective view of a packaging unit corresponding to FIG. 6 (1).

8 is an enlarged detailed view of the packaging portion similar to FIG. 6, in which (1) is a vertical cross-sectional side view showing a pushed-up state of the wrinkle removing member, and (2) is an enlargement of a portion within a circle of (1). It is a figure.

9 is a perspective view corresponding to FIG. 8 (1).

FIG. 10 is a vertical sectional side view showing a pushed-up state of a product (tray).

FIG. 11 is a vertical cross-sectional side view in which the product is further pushed up to the upper limit position.

[Explanation of symbols]

B: Product (tray) 4 ': Film 6: Film transport mechanism 6A: Front belt mechanism 6B: Rear belt mechanism 20: Upper elastic belt 21: Lower elastic belt 22: Clamp plate 30: Wrinkle removing member 32: Parallel link member 34: Solenoid

Claims (4)

(57) [Claims] 1. A stretch packaging in which a film transport mechanism having a transport belt clamps both side edges of the film to transport the film and supply the film to a packaging unit, and the packaging unit pushes up a product toward the film for packaging. In the machine, the inside of the supplied film along the conveyor belt is fed to the wrapping portion from below, and the position of the upper surface at the time of ascent is filled.
It is higher than the transport surface, but it is the highest position where the product is pushed up.
A stretch wrapping machine that is provided with a wrinkle removing member that pushes up and extends to a much lower height to remove wrinkles so that it can be moved up and down. 2. The film transporting mechanism comprises a transporting belt, a film clamp which is in contact with and separated from the transporting belt on each side, and a transporting belt or a contact plate which faces the transporting belt. Stretch wrapping machine. 3. The stretch wrapping machine according to claim 1 or 2, wherein the wrinkle removing member is provided only on one side of the film. 4. A stretch wrapping machine, wherein the wrapping machine folds the last film edge while discharging the product from the wrapping section, wherein the wrinkle removing member is arranged on one side opposite to the product discharge side. The stretch wrapping machine according to claim 3, which is installed.