JP2001097309A - Packaging apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a packaging apparatus capable of preventing creases from generating at the upper part of a film covering a packaged matter, regardless of shapes of a tray or the packaged matter. SOLUTION: A packaging apparatus which thrusts a matter to be packaged against a film held at its both sides and tucks up the periphery of the film onto the bottom of the matter to be packaged comprises a plurality of clamps 25-29, a plurality of tuck-in boards (rods), motors 61a-61e and 62a-62e, and a controller 9. The controller 9 calculates stretching forces of film, based on loads of the motors 61a-61e and 62a-62e, and controls timings for releasing holding of the film by the clamps during packaging works, based on the stretching forces of film around the clamps 25-29.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a packaging device,
The present invention relates to a packaging apparatus that performs a packaging operation in which an object to be packaged is pressed against a film in a state of being held in tension and a peripheral portion of the film is folded toward the bottom of the object to be packaged.

[0002]

2. Description of the Related Art Heretofore, an apparatus for packing a packaged object such as fresh foodstuffs stored in a tray using styrofoam or the like with a stretch film is known as a stretch packaging apparatus. In this stretch packaging apparatus, a stretch film having a predetermined width is cut into a predetermined length according to the size of a tray, and both side edges in the width direction of the film are held by a pair of feeders including upper and lower belts. While transporting the film to the packaging station, the film is packaged at the packaging station. At the packaging station, the goods (hereinafter referred to as “packaged objects”) stored in the tray are pushed up against the film that has been transported and held in tension, and the peripheral portion of the film is held in a state where the packaged objects are in close contact with the film. To the bottom of the tray. As a result, the object to be packaged is wrapped in the stretch film, and then the film on the bottom surface of the tray is heat-sealed to complete the packaging.

[0003] Among the series of such operations, the operation of pushing up the packaged object against the tensioned film and folding the peripheral portion of the film will be described. Grab the spot and pre-stretch the film. Then, while lifting up the packaged object from below against the film in a tensioned state by pre-stretching, release the film holding by the clamp at an appropriate timing, and fold the peripheral portion of the film to the bottom side of the tray by the folding member. . Here, the release timing of the film holding of the clamp and the start timing of the folding member can be manually and finely adjusted to a predetermined numerical value at the time of trial operation. In some cases, the shape of the tray is sensed by a CCD camera, and the timing of releasing the film holding and the timing of starting the folding member are sometimes adjusted using the width and height of the tray as parameters.

[0004]

One of the indices for judging the finishing condition of the film packaging by the stretch packaging device is whether or not the film portion above the tray covering the object to be packaged is finely finished without wrinkles. There is something. If the film is stretched without wrinkles, the value as a product increases, but if the film stretched above the tray has wrinkles, the customer's willingness to purchase the product is reduced.

[0005] In order to prevent wrinkles on the film covering the object to be packaged above the tray, it is necessary to properly hold the film at the packaging station and optimize the timing of releasing the clamp from holding the film and the timing of starting the folding member. Must be set to prevent wrinkling of the film during the packaging operation. For this reason,
Conventionally, the width and height of the tray are used as parameters as described above, and the length of the film is used as a parameter as disclosed in Japanese Patent Application Laid-Open No. 58-160230. As shown in the publication, the vertical width, the horizontal width, the height, and the like of the article to be packaged are used as parameters to control the timing of releasing and folding the film holding. Thus, generation of wrinkles in the film packaging is suppressed to some extent.

However, recently, the shapes of trays used have been diversified, and when a tray having a large curvature at a corner portion or a so-called deformed tray is used, an optimal wrinkle-free film package is obtained only by using the above parameters. Has become difficult to do. In addition, even if the amount of adjustment data set for each tray shape is increased by improving the degree of sensing the planar shape of the tray including the vertical width and the horizontal width by the CCD camera, the bottom shape of the tray is sensed. It is difficult to do so, and there remains a problem that trays having shapes that are not stored cannot be handled.
Further, there are trays having different strength (elasticity) even if they have the same size and shape.

It is an object of the present invention to provide a packaging apparatus capable of performing packaging without forming wrinkles on an upper portion of a film covering an object to be packaged irrespective of the shape of a tray or the shape of an object to be packaged.

[0008]

According to a first aspect of the present invention, a packaging apparatus includes a plurality of holding units, a moving unit, a plurality of folding units, a measuring unit, and a controlling unit. And
This packaging apparatus performs a packaging operation in which an object to be packaged is pressed against a film in a tension-held state, and a peripheral portion of the film is folded toward the bottom of the object to be packaged. The holding means can hold a peripheral portion of the film. The moving means can move the package and press the package against the film. The folding means can fold the peripheral portion of the film against which the package is pressed against the bottom of the package. The measuring means measures the tension of the film during the packaging operation. The control means controls the timing of releasing the holding of the film by the holding means during the packaging operation based on the measurement result of the measuring means.

In the packaging apparatus according to the present invention, the tension of the film is directly measured instead of the indirect parameters such as the shape of the object to be packaged and the length of the film as in the prior art, and the packaging is performed based on the measurement result. The timing of releasing the film holding by the holding means during the operation is controlled. For this reason, it is possible to perform film packaging without wrinkles irrespective of the size and shape of the article to be packaged. By controlling the timing of releasing the holding of the film by the holding means so that a constant tension is always applied to the film during the wrapping operation, the film packaging of the object to be packaged can be completed without wrinkling the film. it can.

According to a second aspect of the present invention, there is provided a packaging device including a plurality of holding means, a moving means, a plurality of folding means, a measuring means, and a control means. This packaging apparatus performs a packaging operation in which an object to be packaged is pressed against a film in a tension-held state, and a peripheral portion of the film is folded toward the bottom of the object to be packaged. The holding means can hold a peripheral portion of the film. The moving means can move the package and press the package against the film. The folding means can fold the peripheral portion of the film against which the package is pressed against the bottom of the package. The measuring means is
Measure the tension of the film during the packaging operation. The control means controls the timing of folding the film by the folding means during the packaging operation based on the measurement result of the measuring means.

In the packaging apparatus of the present invention, the tension of the film is directly measured instead of the indirect parameters such as the shape of the object to be packaged and the length of the film as in the prior art, and the packaging is performed based on the measurement result. The folding timing of the film by the folding means during operation is controlled. For this reason, it is possible to perform film packaging without wrinkles irrespective of the size and shape of the article to be packaged. If the folding timing of the film by the folding means is controlled so that a constant tension is always applied to the film during the packaging operation, the film packaging of the article to be packaged can be completed without wrinkling the film. .

According to a third aspect of the present invention, there is provided a packaging apparatus including a plurality of holding units, a moving unit, a plurality of folding units, a measuring unit, a holding unit moving unit, and a control unit. This packaging apparatus performs a packaging operation in which an object to be packaged is pressed against a film in a tension-held state, and a peripheral portion of the film is folded toward the bottom of the object to be packaged. The holding means can hold a peripheral portion of the film. The moving means moves the package and presses the package against the film. The folding means can fold the peripheral portion of the film against which the package is pressed against the bottom of the package. The measuring means measures the tension of the film during the packaging operation. The holding unit moving means can move the holding means.
The control means controls the tension of the film by moving the holding means during the packaging operation based on the measurement result of the measurement means.

In the packaging apparatus according to the present invention, the tension of the film is directly measured instead of the indirect parameters such as the shape of the object to be packaged and the length of the film as in the prior art, and the packaging is performed based on the measurement result. The tension of the film is controlled by moving the holding means during the operation. For this reason, it is possible to perform film packaging without wrinkles irrespective of the size and shape of the article to be packaged. If the tension of the film is controlled by moving the holding means so that a constant tension is always applied to the film during the packaging operation, the film packaging of the article to be packaged can be completed without wrinkling the film. it can.

A packaging apparatus according to a fourth aspect is the packaging apparatus according to any one of the first to third aspects, wherein the measuring means comprises:
The tension of the film is measured by detecting a load related to the holding of the film by the holding means. Here, in view of the fact that the load relating to the holding of the film by the holding means increases as the tension of the film increases, the method of measuring the tension of the film by detecting the load relating to the film holding is adopted.

According to a fifth aspect of the present invention, there is provided the packaging apparatus according to the fourth aspect, wherein the holding means has a motor for generating a holding force for holding the film. Then, the measuring means detects a load acting on the motor of the holding means. Here, a motor is employed as a source of a holding force for holding the holding film so that the load associated with holding the film can be easily measured. Therefore, the film tension can be measured by a simple method of detecting a load such as a current value or a voltage acting on the motor.

A packaging device according to a sixth aspect is the packaging device according to any one of the first to third aspects, wherein the measuring means comprises:
The tension of the film is measured by detecting the load related to the folding of the film by the folding means. Here, in view of the fact that the load on the folding means increases as the tension of the film increases when the folding means folds the peripheral portion of the film to the bottom side of the packaged object, the load on the folding of the film by the folding means is reduced. The method of measuring the tension of the film by detecting it is adopted.

According to a seventh aspect of the present invention, there is provided the packaging apparatus according to the sixth aspect, wherein the folding means has a motor for folding the film. Then, the measuring means detects a load acting on the motor of the folding means.
Here, the film is folded by a motor so that the load related to the film folding can be easily measured. Therefore, the film tension can be measured by a simple method of detecting a load such as a current value or a voltage acting on the motor.

According to a twelfth aspect of the present invention, there is provided a packaging apparatus for performing a packaging operation in which an object to be packaged is pressed against a film held in tension and a peripheral portion of the film is folded toward the bottom of the object to be packaged. , Measuring means, and control means. The measuring means measures the tension of the film during the packaging operation. The control means controls the packaging operation based on the measurement result of the measurement means.

In the packaging apparatus according to the present invention, the tension of the film is directly measured and the packaging operation is controlled based on the tension instead of the indirect parameters such as the shape of the object to be packaged and the length of the film. Therefore, it is possible to perform film packaging without wrinkles irrespective of the size and shape of the article to be packaged. If the wrapping operation is controlled so that a constant tension is always applied to the film during the wrapping operation, the film packaging of the article to be packaged can be completed without wrinkling the film.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [First Embodiment] FIG. 1 shows a film-transport type packaging apparatus according to an embodiment of the present invention.
This packaging apparatus 1 is an apparatus that pushes up products such as fresh food products placed on a tray against a stretched film F held in tension, and folds a peripheral portion of the film F toward the bottom side of the tray to perform film packaging. . In addition, the packaging device 1 has a weighing function and a labeling function by labeling in addition to a film packaging function.

<Overall Outline of Apparatus> As shown in FIGS. 1 and 2, the packaging apparatus 1 includes a weigh-in / carry-in mechanism 2, a packaging station 3, a roll support mechanism 4, a film delivery mechanism 5, and a film transport mechanism. 6, a folding mechanism 7, and a sealing mechanism 8. The weigh-in / carry-in mechanism 2 includes a main body 1a.
Is provided at the center of the front of the camera. Packaging station 3
Is a space formed in the main body 1a. The roll support mechanisms 4 are arranged on both sides of the main body 1a, and hold the film rolls R, respectively. Film feeding mechanism 5
Sends out the film F pulled out from the film roll R upward. The film transport mechanism 6 receives the film F from the film delivery mechanism 5 and transports the film F to the packaging station 3. The folding mechanism 7 packages the article to be packaged by the film F transported to the packaging station 3. The sealing mechanism 8 performs heat sealing on the film F folded on the bottom side of the packaged object by the folding mechanism 7.

A display panel 9 is provided above the main body 1a.
A control device (control means) 9 having a and operation keys 9b is arranged. The control device 9 includes the mechanisms 2 and 2 described above.
In addition to controlling the operations of 5, 6, 7, and 8, the price of the product G is calculated based on a signal indicating the weight of the product G measured by the weighing-in mechanism 2, and the weight and the price of the product G are calculated. The operation of a label printer 10 and a label issuing machine 11 for printing on a label is controlled.

The film roll R used in the packaging apparatus 1 has a stretch film F having a predetermined width dimension wound multiple times. <Measurement Delivery Mechanism> The measurement delivery mechanism 2 includes a weighing device that measures the weight of a product G such as food stored in the tray T, and a plurality of delivery belts stretched between a pair of rollers.
The carry-in belt is provided with a protrusion for conveyance. If the tray T containing the goods G is placed on the measuring device (above the carry-in belt) as shown in FIG. 3, the weight of the goods G is measured by the measuring device. After being weighed, the tray T is pushed by the protrusion of the carry-in belt, and the lifter mechanism 3 of the packaging station 3 (inside the apparatus) is pressed.
0 (described later) (see FIGS. 14 and 15).

<Packaging Station> Packaging Station 3
Is a space in the main body 1a in which a series of film packaging processing is performed on the goods G in the tray T, which has been weighed. In the packaging station 3, the stretch film F is stretched by the film transport mechanism 6, and the stretched film F is stretched.
The lifter mechanism 30 pushes up the tray T and the product G (see FIG. 16). Then, the folding mechanism 7 folds the peripheral portion of the film F into the bottom surface side of the tray T in a state where the film F is pushed up, so that the tray T and the product G are covered with the film F.

Below the packaging station 3, a lifter mechanism (moving means) 30 for holding the bottom surface of the tray T and moving the tray T and the goods G upward is provided. As shown in FIG. 3, the lifter mechanism 30 includes a support base 31, a plurality of support bars 32 fixed on the support base 31, and a rotatably supported upper end of each support bar 32. And a support member 33 for receiving the bottom surface. In addition, the lifter mechanism 30 includes an electric ball screw mechanism 34 that moves the support base 31 up and down at a lower portion.

Each support bar 32 is provided with a hinge that bends back and forth and right and left at a central portion thereof.
When you enter the lower part of the tent, it will temporarily fall. <Roll Support Mechanism> The roll support mechanism 4 for supporting the film roll R is provided substantially symmetrically on both sides of the main body 1a (see FIGS. 2 and 4). The roll support mechanism 4 mainly includes a roll bar.

The roll bar allows the film roll R to pass therethrough and holds the film roll R with a holder or the like. The roll bar is rotatably supported by the main body 1a, and a belt 4c is hung on a pulley 4b fixed to one end thereof (see FIG. 2). The belt 4c is driven according to the rotation of a film roll drive motor 4d. Further, a film brake 4e is provided between the belt 4c and the film roll drive motor 4d, so that the feeding of the film F from the film roll R can be stopped.

<Film Delivery Mechanism> The film delivery mechanism 5 is a mechanism for delivering the film F drawn from the film roll R to a pair of feeder units 61 and 62 of a film transport mechanism 6 described later. As shown in FIG. 2, the film feeding mechanism 5 mainly includes a feeding roller 51, a feeding motor 52 for rotating the feeding roller 51, and a film insertion plate unit 5.
3 and a film insertion plate drive motor 54 for moving the film insertion plate unit 53 up and down.

The feeding roller 51 is provided with a roll support mechanism 4.
The roller is disposed obliquely above the film roll R held on the outside and outside the film roll R. The feeding roller 51 is connected to a feeding motor 52 via a belt.
And is rotated by the operation of the feeding motor 52. The film insertion plate unit 53 is mainly composed of two plates, and is arranged above the film roll R supported by the roll support mechanism 4 as shown in FIG. This film insertion plate unit 53
Is composed of two plates 57, 58 each having one end connected by a hinge (not shown), and a plurality of one-way rollers 59 supported by the plate 58 (see FIG. 4).

The film insertion plate drive motor 54 is provided to move the film insertion plate unit 53 up and down, and moves the film insertion plate unit 53 up and down via a link mechanism. <Film Transport Mechanism> The film transport mechanism 6 receives the film F fed by the film feed mechanism 5 from the film roll R, and sends it to the packaging station 3.
And the film F is held in tension. The film transport mechanism 6 mainly includes a first feeder unit 61, a second feeder unit 62,
It is composed of a feeder moving unit 63, a second feeder moving unit 64, and a feeder driving unit 65.

The first feeder unit 61 is on the near side as viewed from the front of the apparatus 1, and the second feeder unit 62 is
(See FIGS. 3 and 4). These first and second feeder units 6
1, 62 sandwich the film F to be fed laterally (the front side and the opposite side) between the upper and lower belts, and transport the film F by the operation of the feeder drive unit 65.

The first feeder unit 61 is actuated by the first feeder moving unit 63 and the second feeder unit 62 is actuated by the second feeder moving unit 64 in the film width direction (the left and right direction in FIGS. 3 and 4). ) Is configured to move. Each of the feeder units 61 and 62 is supported by slide shafts 66 and 67 extending along the film width direction at two locations so as to be movable in the film width direction.

As shown in FIG. 5, each feeder moving unit 63, 64 has drive motors 63a, 64a, and belts 63b, 64b which move in both directions in the film width by the operation of the drive motors 63a, 64a. I have. Then, each feeder unit 61, 62 is connected to each belt 63b,
64b (see FIG. 5).
By the operation of a and 64a, the feeder units 61 and 62 can individually move in the film width direction.

(Details of Feeder Unit) Next, the structure of the first and second feeder units 61 and 62 will be described in detail. Since the configurations of the two feeder units 61 and 62 are substantially the same, the first feeder unit 61 will be described below as an example. FIGS. 6 to 8 show the first feeder unit 61.
FIG. These drawings include clamps 25 to 29 which are not shown in FIGS. 1 to 5. FIG. 9 is a top view of the first and second feeder units 61 and 62 including the clamps 25 to 29, and FIG.
FIG. 10 shows the arrangement of the clamps 25 to 29 extracted from FIG.
Shown in

As shown in these figures, the first feeder unit 61 includes a frame 21, a lower belt 22, an upper belt 23, an introduction belt 24, a main clamp 25,
26 and 27 and auxiliary clamps 28 and 29 are provided. (Frame) The frame 21 is composed of belts 22 to 24.
, The clamps 25 to 29, and the motors 61 a to 61 e for moving the clamps 25 to 29
(See FIG. 12), and constitutes the skeleton of the first feeder unit 61. Also, this frame 21
Is a strip 21a having substantially the same width as the belts 22, 23 between the upper belt and the lower belt of the lower belt 22.
have. The band plate 21a has a role of sandwiching the belts 22, 23 and the film F between the main clamps 25, 26, 27 described later.

(Belt) The lower belt 22 is in contact with the film F from below, and is stretched over six pulleys as shown in FIG. One of these pulleys is connected to the drive motor 65a of the feeder drive unit 65 via a plurality of belts, as shown in FIG. When the drive motor of the feeder drive unit 65 operates,
The lower belts 22 of both feeder units 61 and 62 move in synchronization.

The upper belt 23 rides on the lower belt 22 and follows the movement of the lower belt 22. The upper belt 23 is stretched over four pulleys. The introduction belts 24 are respectively arranged outside both ends in the longitudinal direction of the lower belt 22 and are in contact with a vertically extending portion of the lower belt 22. The introduction belt 24 can be switched between a state shown by a solid line and a state shown by a dashed line in FIG. In the state shown by the one-dot chain line in FIG.
And a film F held by the film insertion plate unit 53 of the film feeding mechanism 5 can enter the gap. That is, the introduction belt 24 has a role of sandwiching the film F sent from below by the film delivery mechanism 5 with the lower belt 22 and guiding it between the lower belt 22 and the upper belt 23.

(Main Clamp) Main clamp 25,
The belts 26 and 27 are disposed between the upper belt and the lower belt of the upper belt 23.
It is arranged at a position overlapping 2 and 23. These clamps 25, 26, 27 are connected to each other via a link mechanism as shown in FIG.
The fourth motor 61d, the third motor 61c, and the second
Motor 61b (clamp 2 of second feeder unit 62)
5, 26 and 27 are a ninth motor 62d and an eighth motor 62
c, and by the seventh motor 62b). These motors 61d, 61c, 61b are fixed to the outer surface of the frame 21. The clamps 25, 26, 27 do not normally apply a force to both belts 22, 23, but are depressed when the motors 61d, 61c, 61b operate, and the lower belt of the upper belt 23 and the upper belt of the lower belt 22 are moved. And a downward force is applied to the belt and the belt 21a. Therefore, when the film F is between the lower belt 22 and the upper belt 23, the motor 6
By operating 1d, 61c, 61b, the film F is held in close contact with both belts 22, 23, and the motors 61d, 61c,
When the operation of 61b is stopped, the holding of the film F is released.

(Auxiliary Clamp) Auxiliary Clamps 28 and 29
Are the main clamps 2 that are aligned in a plane
5, 26, 27. Specifically, as shown in FIG.
6 and 27 are arranged so as to overlap the belts 22 and 23, and the film F is gripped together with the belts 22 and 23 to strongly hold the film F, whereas the auxiliary clamps 28 and 29 are shifted inward from the belts 22 and 23. Placed on film F
Is held directly and the film F is held.
Hereinafter, since the configuration of the auxiliary clamps 28 and 29 is the same, the auxiliary clamp 28 will be described as an example.

As shown in FIGS. 6 to 8, the auxiliary clamp 28 mainly includes a fixed contact portion 28a located above the film F and a movable contact portion 28b located below the film F. It is composed of When the moving contact portion 28b moves upward, the film F is strongly clamped by the fixed contact portion 28a and the moving contact portion 28b, and the film F is clamped.

The fixed contact portion 28a is a plate member that extends long in the film transport direction (the left-right direction in FIG. 7 and the up-down direction in FIG. 10), and has a rounded lower surface to protect the film F. This fixed contact portion 28a is fixed to the frame 21 via an L-shaped fixing tool 28d (FIG. 8).
reference). The moving contact portion 28b is moved up and down by a fifth motor 61e (see FIG. 12) via a link mechanism 28c. The movable contact portion 28b also extends in the film transport direction, but the movable contact portion 28b has a shorter length in the film transport direction than the fixed contact portion 28a. The link mechanism 28c is supported by the frame 21 via a fixture 28e (see FIG. 8), and the fifth motor 61e is fixed to the inner surface of the frame 21.

<Cutter Mechanism> A cutter mechanism 69 is provided in front of the film transport mechanism 6 in the film transport direction. The cutter mechanism 69 is provided to cut the film F between the two mechanisms 5 and 6 after the film F transferred from the film delivery mechanism 5 to the film transport mechanism 6 is transported by the film transport mechanism 6 by a predetermined amount. Is provided. The cutter mechanism 69 has a cutting blade 69a longer than the film width, and cuts the film F by moving the cutting blade 69a with an actuator (see FIG. 2).

<Folding Mechanism> The folding mechanism 7 is shown in FIG.
As shown in FIG. 3 and FIG.
6, 77, a rear folding plate 78, and a front folding rod 79. The left and right folding plates 76 and 77 fold both ends of the film F in the film transport direction toward the bottom side of the tray T, and can be moved horizontally by a left and right folding motor 7a (see FIG. 13) and a timing belt (not shown). is there.

The rear folding plate 78 folds the side of the film F on the side of the second feeder unit 62 toward the bottom of the tray T, and is driven by a rear folding motor 7b (see FIG. 13) and a timing belt (not shown). Horizontal movement is possible. The front folding rod 79 connects the tray T to the sealing mechanism 8.
When the tray T is discharged by the discharge pusher 79a that is pushed out toward the side, the side portion of the film F on the first feeder unit side is arranged to be folded into the bottom surface side of the tray T. The discharge pusher 79a can be moved horizontally by a discharge pusher motor 7c (see FIG. 13) and a timing belt (not shown).

<Seal Mechanism, Label Printer, Label Issuer> The seal mechanism 8 serves to heat and seal the bottom surface of the tray T extruded by the discharge pusher 79a, and the front part also functions as a discharge table. Also serves as. Then, the label issuing machine 11 affixes the label printed by the label printer 10 to the packaged product discharged here.

<Control Device> The control device 9 arranged on the upper part of the main body 1a is connected to each part as shown in FIG. 11, and each mechanism 2, 5, 6, 30, 7, 8, 10, 11 Each operation is controlled. The operation by the operator includes not only the operation key 9b but also the switches and dials 16, 17, 1
8 and 19 are also accepted.

FIG. 12 is a schematic diagram showing the connection between the control device 9 and each motor of the film transport mechanism 6, and FIG. 13 is a schematic diagram showing the connection between the control device 9 and each motor of the folding mechanism 7. . As shown in these figures, the motors 61a to 61e, 62a to 62e, 63a, 64
a, 65a and motors 7a, 7b, 7 of the folding mechanism 7
c are each independently connected to the controller 9;
Each is operated separately. Further, the control device 9 can grasp the load applied to each motor based on a current value or based on a rotation speed obtained from a counter or the like.

Then, the control device 9 controls the motors 61a to 61e, 6
The release timing of the film holding of the clamps 25 to 29 during the folding operation is controlled according to the tension at each part of the film F calculated from the load applied to 2a to 62e as described later. <Outline of Operation of Packaging Apparatus> Next, the operation of the packaging apparatus 1 having the above configuration will be briefly described.

In this apparatus 1, as shown in FIG. 14, when the operator places the tray T containing the product G on the weighing device of the weighing-in / carrying-in mechanism 2, the weighing value is stabilized and the weighing is completed. , The loading belt starts to move. The protrusion fixed to the carry-in belt moves according to the movement of the carry-in belt,
The tray T on which the product G is placed is pushed out onto the support member 33 of the lifter mechanism 30 (see FIG. 15).

On the other hand, the film F transferred from the film roll R to the film transport mechanism 6 by the film feeding mechanism 5 is cut by the cutter mechanism 69 and is formed into a single rectangular film F by the lifter mechanism 30. It is carried to the upper side by both feeder units 61 and 62. Above the lifter mechanism 30, the periphery of the film F is strongly held by the operation of the clamps 25 to 29.

Then, the lifter mechanism 30 pushes up the commodity G and the tray T against the film F whose periphery, especially both sides, are strongly held as described above (see FIG. 16). Then, the film F, which is strongly held around, extends so as to cover the commodity G and the upper part of the tray T. In this state, when the rear folding plate 78 and the left and right folding plates 76 and 77 move horizontally to the bottom side of the tray T, the clamps 25 to 29 other than the clamps on the front side (the left side in FIG. Is released, and the three sides of the film F are folded under the tray T. When the discharge pusher 79a pushes the tray T toward the sealing mechanism 8, one side of the unfolded front side film F hits the front folding rod 79, and the sealing mechanism 8
As the tray T moves to the side, it is folded under the tray T. The clamp on the front side is released from holding the film F at this time. Also, during this movement, when the film F folded under the tray T is heat-sealed and discharged to the position shown in FIG. Becomes

Further, when a process including label sticking is selected, the price and weight of the product calculated based on the weighed value are printed on the label by the label printer 10 and the label is printed by the label issuing machine 11. To the packaged product G and the tray T. <Film Folding Operation of Packaging Device> Next, the clamps 25 to 29 of the first and second feeder units 61 and 62 are described.
The film folding operation for folding the film F strongly held by the lower part of the tray T will be described in more detail with reference to FIGS.

FIG. 18 shows a lifter mechanism 30 (not shown).
7 shows a state in which the tray is lifted above the rear folding plate 78 and the left and right folding plates 76 and 77. FIG. 18A shows a state when viewed from the side, and FIG. 18B shows a state when viewed from the front. Here, the film F is stretched to some extent, and the products in the tray T are covered with the film F stretched.

When the tray T is lifted up to the state shown in FIG. 18, the rear folding plate 78 and the left and right folding plates 7
6, 77 move horizontally toward the space below the tray T. Then, as shown in FIGS. 19A and 19B, the rear folding plate 78 and the left and right folding plates 76 and 77 start pushing the film F from the side. At this time, the positions of the first and second feeder units 61 and 62 including the clamps 25 to 29 (only a part is shown in the drawing) have not changed.

Further, when the rear folding plate 78 and the left and right folding plates 76 and 77 further move and their leading ends enter the lower side of the tray T to some extent, as shown in FIG. 64 drive motors 64a
Operates, and the second feeder unit 62 (FIG. 20A)
(Including the clamp 28 on the right side of the drawing) comes inward in the film width direction.

Then, the rear folding plate 78 reaches a predetermined position.
When the left and right folding plates 76 and 77 advance, the film holding of the clamps 25 to 29 is sequentially released (see FIG. 21). Thereafter, the rear folding plate 78 and the left and right folding plates 76 and 77 are further moved, and the three sides of the film F except the front side (the left side in FIG. 21A) are folded under the tray T. Becomes At this time, except for the front-side clamp (the main clamp 26 of the first feeder unit 61 in FIG. 22), the clamps 25 to 29 are in a state where the holding of the film F is released. The timing of releasing the holding of the clamps 25 to 29 with respect to the movement of the rear folding plate 78 and the left and right folding plates 76 and 77 will be described later in detail.

Then, as described above, the discharge pusher 7
When the tray T is pushed to the sealing mechanism 8 side at 9a, one side of the unfolded front side film F hits the front folding rod 79, and the lower side of the tray T follows the movement of the tray T to the sealing mechanism 8 side. It is folded into. At this time, the holding of the film F by the main clamp 26 on the front side is released. The timing of releasing the front main clamp 26 from holding the film in response to the movement of the discharge pusher 79a will be described in detail below.

<Control of Clamp Holding Release and Folding Operation by Control Device> At the time of the folding operation, the control device 9 monitors the current value and the like to apply a holding force to each of the clamps 25 to 29 of the film transport mechanism 6. First motor 61a to fifth motor 61e and sixth motor 6 to be generated
The load acting on the second motor to the tenth motor 62e is constantly detected. Then, the load applied to the motor is converted into the film tension based on the correlation data obtained in advance by the test. As described above, the control device 9 controls each part of the film F (each clamp 25 to
(Part held at 29) can always be grasped.

The release timing of the film holding of each of the clamps 25 to 29 is determined according to the film tension of the portion held by each of the clamps 25 to 29.
It is determined that the load of 61e, 62a to 62e reaches a value corresponding to a predetermined tension. That is, each motor 61
When the current values and the rotation speeds of a to 61e and 62a to 62e reach a predetermined level, the control device 9 causes the clamps 25 to 29 to operate.
It is determined that the tension of the portion of the film held by the clamp has reached a predetermined value, and the film holding by the clamp is released.

In this manner, the release timing of the clamps 25 to 29 when the folding plates 76, 77, 78 move during the folding operation, or the discharge side pusher 79a and the front folding rod 79 cause the front film F to be released. The release timing of the front side clamp 26 at the time of folding is controlled based on the film tension. Each of the clamps 25 to 29 in the actual folding operation
The release timing of the film holding depends on the shape of the tray T and the size of the film F. For example, if the tray T has a shape as shown in FIG. 22, the order is as shown in FIG. The order and the release timing are controlled so that the tension (tension) of each portion of the film F to be folded is substantially equal at the time of holding release, so that a good-looking film packaging is performed. . That is, here, first, the holding of the second feeder unit 62 by the auxiliary clamps 28, 29 is released (see No. 1 in FIG. 22), and then, the holding of the first feeder unit 61 by the auxiliary clamps 28, 29 is released. Next, the four holdings of the main clamps 25 and 27 of both feeder units 61 and 62 are released (see FIG. 2).
2), then the second feeder unit 62
The holding of the main clamp 26 at the center of is released (see number 4 in FIG. 22). The holding of the main clamp 26 of the first feeder unit 61, which is released when the discharge pusher 79a is operated, is finally released (see No. 5 in FIG. 22).

In the case of packing a tray larger than that shown in FIG. 22, the main clamp 25 of the first feeder unit 61, until the discharge pusher 79a operates.
It is possible that all 26 and 27 continue to hold film F. <Motion Control of Second Feeder Unit During Folding Operation by Control Device> Next, control of the movement timing of the second feeder unit 62 during the folding operation will be described.

As described above, before the film holding of each of the clamps 25 to 29 is released, the drive motor 64a of the second feeder moving unit 64 operates to operate the second feeder unit 62 (FIG. 20 (a)). (Including the clamp 28 on the right side) is moved inward in the film width direction (see FIG. 20). By moving the clamps 25 to 29 of the second feeder unit 62 inward in accordance with the movement of the second feeder unit 62, without causing the film F to be loosened and without applying excessive tension to the film F, The folding of the film F can be completed.

The timing at which the movement of the second feeder unit 62 is started depends on the film tension of the portion held by the clamps 25 to 29 of the second feeder unit 62, and specifically, the load of the motors 62a to 62e. Is determined to have reached a value corresponding to a certain tension. That is, when the current value or the rotation speed of any of the motors 62a to 62e reaches a certain level, the control device 9 starts moving the second feeder unit 62 inward to reduce the increase in the film tension.

As described above, in the present packaging apparatus 1, the movement timing of the second feeder unit 62 when the folding plates 76, 77, and 78 move during the folding operation is determined by the following.
It is controlled based on the film tension. <Characteristics of this packaging device> (1) In this packaging device 1, the tension of the film F during the folding operation is not an indirect parameter such as the shape of the tray T and the product G or the length of the film F as in the conventional case. Is detected directly, and the folding operation is controlled based on the detection result. Specifically, each of the motors 61a to 61e, 62
The film tension is calculated from the loads applied to a to 62e, and the release timing of the clamps 25 to 29 and the movement timing of the second feeder unit 62 are determined based on the calculated film tension.

For this reason, regardless of the size or shape of the tray T or the product G, the film can be wrapped under a constant tension, and wrinkles occur on the film F above the tray T after wrapping. Absent. As a result, it is possible to perform good-quality film packaging without wrinkles on trays and products of various shapes and trays of various materials without measuring the size and shape of the tray T and the product G. It is possible.

(2) In the packaging apparatus 1 of this embodiment, the conventionally used main clamps 25, 26, 27
In addition, auxiliary clamps 28 and 29 are provided. The auxiliary clamps 28, 29 strongly hold the film F at a portion inside the side of the film F held by the main clamps 25, 26, 27 (see FIG. 10).

Therefore, in the present packaging apparatus 1, a conventional packaging apparatus in which the film F is held only at both sides is provided.
The product G and the tray F are approaching a state where the film F to be pressed is held from all sides. That is, since the auxiliary clamps 28 and 29 hold portions slightly inside the side portions of the film F, the products G and Push the tray T up and the product G on the tray T with the film F
Wrinkles generated on the film F when the film F is covered (see FIGS. 16 and 18).

Accordingly, wrinkles can be formed not only on a normal rectangular or square tray but also on a deformed tray having a curved portion or the like, which is difficult to cleanly package a film with a conventional packaging apparatus. No clean film packaging is possible. For example, a good-looking film package with no wrinkles is possible for the irregularly shaped tray T as shown in FIG. 22 and also for the three-dimensionally irregularly shaped tray.

[Second Embodiment] In the first embodiment, the first motor 61a to the fifth motor 61 that generate the holding force of the clamps 25 to 29 of the film transport mechanism 6 are used.
e, control is performed to determine the tension at each part of the film F from the load applied to the sixth motor 62a to the tenth motor 62e to determine the release timing of the clamp. It is also possible to perform control such that the film tension is determined and the release timing of the clamp is determined.

For example, when the tray T is pushed toward the sealing mechanism 8 by the discharge pusher 79a, the release timing of the front side clamp 26 is determined by the discharge pusher motor 7c.
The load applied to the discharge pusher motor 7c can be determined from the change in the current value or the change in the rotation speed, and the load can be determined based on this load. The release timing of each of the auxiliary clamps 28 and 29 can be determined based on the load applied to the left and right folding motor 7a.

[Third Embodiment] In the first embodiment, the tension of each part of the film in the vicinity of each of the clamps 25 to 29 is determined by the loads of the motors 61a to 61e and 62a to 62e for operating the clamps 25 to 29 to generate the holding force. However, instead of this, a pressure sensor is connected to each of the clamps 25 to 2.
9 to measure the film tension.

As shown in FIG. 23, in this embodiment, each of the clamps 25 to 29 has a pressure sensor S1 to S1 respectively.
0 is provided. These pressure sensors S1 to S10
Is attached to a portion of each of the clamps 25 to 29 that applies a force to the film F from above. For example, a pressure sensor S5 is mounted on the auxiliary clamp 28 at a position as shown in FIG. Thus, when the film F is pulled obliquely upward (see FIG. 18), pressure acts on the pressure sensor from the film F (via the upper belt 23 in the case of the main clamps 25 to 27). Therefore, pressures approximately proportional to the film tension act on the pressure sensors S1 to S10, and the control device 9 to which pressure data is sent from these pressure sensors S1 to S10.
Can grasp the film tension of the portion held by each of the clamps 25 to 29.

[Fourth Embodiment] In the third embodiment, the clamps 25 to 29 are connected to the motors 61a to 61e, 62a to 62e.
Although it is operated by 62e (see FIG. 23), if the pressure sensors S1 to S10 are provided in each of the clamps 25 to 29, as shown in FIG.
161a to 161e, 162a to 162e
It is also possible to operate by.

Here, the solenoids 161a to 161
e, 162a-162e, each clamp 25-29
Solenoids 161a to 161 for generating a holding force
e, it is difficult to determine the film tension from the state on the 162a-162e side, but the pressure sensors S1-S10
Is attached to each of the clamps 25 to 29, so that the film tension can be calculated therefrom.

[Fifth Embodiment] In the third and fourth embodiments, the pressure sensors S1 to S10 are connected to the clamps 25 to 2 respectively.
9, the film tension in the vicinity of each clamp is calculated.
It is also possible to provide pressure sensors S11 to S21 at 7, 78 and determine the film tension based on the pressure data from these sensors to control the release timing of each of the clamps 25 to 29.

As shown in FIG. 26, in this embodiment, the pressure sensors S11 to S16 are arranged on the left and right folding plates 77, and the pressure sensors S16 to S21 are arranged on the rear folding plate 78. Each pressure sensor is mounted on the tip of each of the folding plates 77 and 78 that comes into contact with the film F.
Then, each of the pressure sensors S11 to S21 detects when the folding plates 77 and 78 fold the film F.
Detects the reaction force received from the
Send to

The pressure sensor S11 is disposed at a position on the front side of the film F, specifically, at a position where the clamps 25 to 29 of the first feeder unit 61 come. The pressure sensors S12 to S16 are arranged at positions on the other side of the film F, specifically, at positions where the clamps 25 to 29 of the second feeder unit 62 come. These S1
2 to S16 are arranged at five locations in the film width direction so as to be able to correspond to five types of films F having different film widths. Thus, the tension at each position of the film F held by the clamps of the first and second feeder units 61 and 62, in particular, the auxiliary clamps 28 and 29 can be calculated.

The pressure sensors S16 to S21 are arranged at five positions in the film transport direction. These S16 to S2
1 is a clamp 29, 27, 26, 25, 2 respectively.
8 are arranged so as to correspond to positions in the film transport direction. Thereby, the tension at each position of the film F held by each of the clamps 25 to 29 can be calculated.

Here, each of the feeder units 61 and 6 is based on the film tension converted from the pressure data from the pressure sensors S11 to S16 and the pressure sensors S17 and S21.
The release timing of the second auxiliary clamps 28 and 29 is determined,
Each feeder unit 6 based on the film tension converted from the pressure data from the pressure sensors S17, S18, S19.
The release timings of the main clamps 25, 27 of the first feeder unit 62 and the main clamp 26 of the second feeder unit 62 are determined, and the main clamp 26 of the first feeder unit 61 is determined based on the film tension converted from the load applied to the discharge pusher motor 7c. The release timing is determined (see FIGS. 26 and 22).

[Sixth Embodiment] In the fifth embodiment, the pressure sensors S1 are provided at the tips of the folding plates 77 and 78.
6 to S21 are mounted, but the leading ends of the folding plates 77 and 78 are divided and elastically connected to the folding plate main body so that the reaction force applied to the folding plates 77 and 78 from the film F can be measured more accurately. May be.

When the leading end portions of the folding plates 77 and 78 are divided, the pressure sensor can be provided not at the leading end in contact with the film F but at the connecting portion between the divided leading end portion and the folding plate main body. It is.

[0082]

According to the present invention, the tension of the film is directly measured and the packaging operation is controlled based on the measured value instead of the indirect parameters such as the shape of the object to be packaged and the length of the film as in the prior art. Therefore, it is possible to perform film packaging without wrinkles irrespective of the size or shape of the article to be packaged. If the wrapping operation is controlled so that a constant tension is always applied to the film during the wrapping operation, the film packaging of the article to be packaged can be completed without wrinkling the film.

[Brief description of the drawings]

FIG. 1 is an external perspective view of a packaging device according to an embodiment of the present invention.

FIG. 2 is a schematic front view of the inside of the packaging device.

FIG. 3 is a schematic view taken along the line III-III in FIG. 2;

FIG. 4 is a schematic plan view of the inside of the packaging device.

FIG. 5 is a correlation diagram of a feeder unit and a feeder moving unit.

FIG. 6 is a front view of the feeder unit.

FIG. 7 is a plan view of the feeder unit.

FIG. 8 is a side view of the feeder unit.

FIG. 9 is a plan view of a feeder unit.

FIG. 10 is a plan layout view of a clamp.

FIG. 11 is a block diagram of a control device.

FIG. 12 is a connection diagram of a control device and a film transport mechanism.

FIG. 13 is a connection diagram of a control device and a folding mechanism.

FIG. 14 is a diagram illustrating the operation of the packaging device.

FIG. 15 is an explanatory diagram of the operation of the packaging device.

FIG. 16 is an operation explanatory view of the packaging device.

FIG. 17 is an operation explanatory view of the packaging device.

FIG. 18 is an explanatory view of a folding operation.

FIG. 19 is an explanatory view of a folding operation.

FIG. 20 is an explanatory diagram of a folding operation.

FIG. 21 is an explanatory diagram of a folding operation.

FIG. 22 is a drawing showing a sequence of releasing holding of a clamp.

FIG. 23 is a connection diagram of a control device and a film transport mechanism of the third embodiment.

FIG. 24 is a layout diagram of a pressure sensor according to a third embodiment.

FIG. 25 is a connection diagram of a control device and a folding mechanism according to a fourth embodiment.

FIG. 26 is a connection diagram of a control device and a folding mechanism according to a fifth embodiment.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 packaging device 6 film transport mechanism 7 folding mechanism 9 control device (control means) 7a left / right folding motor 7b rear folding motor 7c discharge pusher motor (measuring means) 25, 26, 27 main clamp (holding means) 28, 29 auxiliary clamp ( Holding means) 30 Lifter mechanism (moving means) 61 First feeder units 61a to 61e First to fifth motors (measuring means) 62 Second feeder units 62a to 62e Sixth to tenth motors (measuring means) 63 First feeder Driving unit (holding part moving means) 64 Second feeder moving unit (holding part moving means) 63a Driving motor of first feeder driving unit 64a Driving motor of second feeder moving unit 65a Driving motor of feeder driving unit 76, 77 Left / right folding Plate (folding means) 78 Folding plates (folding means) 79 before folding bars (folding means) 79a discharge pusher 161a~161e first to fifth solenoid 162a~162e sixth to tenth solenoid F film G Product T tray S1~S21 pressure sensor (measuring means)

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Susumu Kimoto Inventor F-term (reference) 3E051 AA08 AB06 BA12 CA08 CB05 DA10 EB03 EB02 EB10 FB02 FC02 at 959 Shimoda, Kurito-cho, Kurita-gun, Shiga Prefecture HA02 HA08 HC03 HE01 JA02 KA02 KA03 KA07 KA08 KB01 LA02 LA04 LA07 LA08 LA09 LB05

Claims (8)

[Claims] 1. A packaging apparatus for performing a packaging operation in which a packaged object is pressed against a film held in tension and a peripheral portion of the film is folded toward the bottom side of the packaged object. A plurality of holding means, a moving means for moving the packaged object and pressing the packaged object against the film, and a plurality of means capable of folding the periphery of the film against which the packaged object is pressed against the bottom side of the packaged object. Folding means, measuring means for measuring the tension of the film during the packaging operation, and control means for controlling the timing of releasing the holding of the film by the holding means during the packaging operation, based on the measurement result of the measuring means, Equipped packaging equipment. 2. A packaging device for performing a packaging operation in which a packaged object is pressed against a film in a state of being held in tension and a peripheral portion of the film is folded toward a bottom side of the packaged object. A plurality of holding means, a moving means for moving the packaged object and pressing the packaged object against the film, and a plurality of means capable of folding the periphery of the film against which the packaged object is pressed against the bottom side of the packaged object. Folding means, measuring means for measuring the tension of the film during the packaging operation, and control means for controlling the timing of folding of the film by the folding means during the packaging operation based on the measurement result of the measuring means. Packaging equipment. 3. A packaging apparatus for performing a packaging operation in which an object to be packaged is pressed against a film held in tension and a peripheral portion of the film is folded toward the bottom side of the object to be packaged, wherein the peripheral portion of the film is held. A plurality of holding means, a moving means for moving the packaged object and pressing the packaged object against the film, and a plurality of means capable of folding the periphery of the film against which the packaged object is pressed against the bottom side of the packaged object. Folding means; measuring means for measuring the tension of the film during the packaging operation; holding part moving means capable of moving the holding means; and moving the holding means during the packaging operation based on the measurement result of the measuring means. And a control means for controlling the tension of the film. 4. The packaging apparatus according to claim 1, wherein said measuring means measures the tension of the film by detecting a load associated with holding the film by said holding means. 5. The apparatus according to claim 4, wherein said holding means has a motor for generating a holding force for holding the film, and said measuring means detects a load acting on the motor of said holding means. A packaging device as described. 6. The packaging apparatus according to claim 1, wherein said measuring means measures the tension of the film by detecting a load related to folding of the film by said folding means. 7. The packaging apparatus according to claim 6, wherein the folding means has a motor for folding the film, and the measuring means detects a load acting on the motor of the folding means. 8. A packaging apparatus for performing a packaging operation in which a packaged object is pressed against a film in a tension-held state, and a peripheral portion of the film is folded toward the bottom side of the packaged object. A packaging apparatus comprising: a measuring unit for measuring a tension; and a control unit for controlling a packaging operation based on a measurement result of the measuring unit.