JP4953592B2 - Packaging equipment - Google Patents

Description

  The present invention relates to a packaging device that wraps an article to be packaged with a film after the article to be pushed up from below toward a film stretched on a packaging unit.

In this type of packaging apparatus, a film is drawn from a film roll, and both side edges in the width direction of the film are sandwiched by a pair of conveyance belts and conveyed to a packaging unit. The drawn film is cut with a cutter in accordance with the size of the package (Patent Document 1).
Japanese Patent Laid-Open No. 9-12008

  At the time of the cutting, the film feeding is stopped and the cutting is performed during the stop. In this method, the film feed is stopped, but the film roll is rotated by inertia and the film is unwound, so that the film is slack and cannot be cut linearly. Therefore, when the stretch rate (stretch rate) of the film is increased, the film may be torn.

  Accordingly, an object of the present invention is to provide a packaging device that can prevent a film from being loosened during cutting and obtain a linear cut line.

  In order to achieve the above object, the packaging device of the present invention is a packaging device that pulls out a film from a film roll, conveys it to a packaging unit, covers the upper surface of the article to be packaged with the film in the packaging unit, and packages the package. Pulling out the film from the film roll and conveying the film toward the packaging part, a cutter for cutting the film drawn from the film roll, and removing the film from the film roll by a predetermined length During the first period of drawing out, during the second period during which the film is cut while further drawing out after the first period, and during the third period during which the cut film is conveyed to a predetermined position of the packaging unit. The speed of the film during the second period is less than the speed of the film during the first period. Control means for controlling the driving of the conveying means so as to be smaller, and an unwinding roller loaded with the film roll and driven to rotate by a motor, from the high-speed conveyance in the first period to the cutting. Further, the control means controls so as to temporarily decelerate the rotation of the unwinding roller.

  According to the present invention, since the drawing of the film is not interrupted during the second period in which the film is cut, there is no slack in the film between the conveying means and the film roll, and the film is in tension. Since the film is cut, the cut line of the film can be linear. Moreover, since the speed of the film during the second period is lower than the speed of the film during the first period, the tension applied to the film can be set to an appropriate level, and the cut line becomes clean.

In this invention, it is preferable that the said control means controls the drive of the said conveyance means so that the speed of the film of the said 3rd period may become larger than the speed of the film of the said 2nd period.
According to this aspect, since the film can be quickly transported to the packaging part after the film is cut, it is possible to prevent a reduction in packaging cycle time.

In the present invention, it is preferable that the control unit temporarily stops driving the transport unit at the end of the first period.
Since the length of the film used for packaging (film length) is determined by the length of the film drawn up to cutting, it is easy to control the film length by temporarily stopping the film drawing at the end of the first period. Thus, the accuracy of the film length can be improved.

In the present invention, the apparatus further includes an unwinding roller loaded with the film roll and rotationally driven by a motor, and temporarily decelerates the rotation of the unwinding roller between the high-speed conveyance and the cutting in the first period. It is preferable to control such that
When the film roll rotates by inertia, the film roll rotates even if the drawing of the film is interrupted. On the other hand, by temporarily decelerating the rotation of the unwinding roller without stopping it, rotation due to the inertia of the film roll can be prevented without generating a large tension on the film. Can be prevented.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
In the following description, the tray T in which the contents are stored will be described as an example of the packaged item. However, the packaged item may be a product that is not placed on the tray T.

First, the basic structure and operation of the packaging device will be described.
As shown in FIG. 1, the present packaging apparatus is a front discharge type packaging apparatus that carries an article to be packaged from the front side 2a and packages it, and then discharges it to the front side 2a. The supply device 20 is provided.

  In FIG. 2, the supply device 20 supplies a tray (object to be packaged) T on which the contents M are placed on the lifter 201. Each post 210 of the lifter 201 is disposed immediately below a packaging station (packaging section) S of the packaging mechanism 200 and can be moved up and down by an elevating means 208. When the tray T is supplied from the supply device 20, the lifter 201 rises and lifts the tray T to the packaging station S.

On the other hand, the stretched film F is supplied to the packaging station S by a pair of conveying belts 3 and 3 prior to the packaging operation. The film F comes into close contact with the upper surface of the tray T when the tray T is pushed up. In this state, the film folding mechanism 203 has a pair of left and right folding plates 204, 204, a rear folding plate 205, a round bar-shaped front folding member 206, and a pusher 207 (FIG. 2) to The left and right side edges are folded and packaged on the bottom side of the tray T, and the packaged tray T is conveyed onto the heat welding conveyor 10 of FIG. The heat welding conveyor 10 welds the films F folded on the bottom surface to each other, and then the tray T is discharged onto the discharge table 209.
In addition, a label is stuck on the packaged product M to be discharged by the label sticking machine 12 (FIG. 1).

Film supply mechanism:
As shown in the schematic cross-sectional view of FIG. 4, a pair of a film supply mechanism including a film passing means 5 and a cutting device 6 and a film roll Fr are provided on both sides in the left-right direction of the apparatus. One of the left and right film supply mechanisms is selected, and the film F is supplied to the packaging station S by the transport belts (supply means) 3 and 3.

The film transfer means 5 transfers the film F drawn from the film roll Fr to the transport belts 3 and 3. The conveying belts 3 and 3 sandwich both side edges Fe of FIG. 3 along the conveying direction Y of the film F, and draw out the film F toward the packaging station S of FIG.
The cutting device 6 cuts the film F between the film transfer means 5 and the conveyor belts 3 and 3 after the film F has been drawn out by a predetermined amount by the conveyor belts 3 and 3.
In addition, the said film supply mechanism is comprised substantially symmetrically, and the following description demonstrates mainly the right side part.

The film transfer means 5 includes a pair of film insertion plates 51 and 52 and a plurality of one-way rollers 53 (FIG. 5) supported by the film insertion plate 51.
FIG. 5 shows the film insertion plates 51 and 52 from the side. The film insertion plates 51 and 52 shown in FIG. 5 sandwich the leading end side of the film F passed to the conveyor belts 3 and 3, and are between the entry end position P2 indicated by a broken line and the retracted end position P1 indicated by a solid line in FIG. Move up and down. The film insertion plates 51 and 52 pass the leading end F2 of the film to the conveyor belts 3 and 3 at the entry end position P2.

  The one-way roller 53 is in contact with the surface of the film F so that the film F sandwiched between the film insertion plates 51 and 52 does not fall down and can rotate only in one direction. The film F is allowed to be pulled out.

6 and 7 are schematic front views showing the film F supply and cutting operations.
As shown in FIG. 6A, the cutting device 6 includes a cutter 61 and a chopping base 62. The cutter 61 includes presser plates 63 and 63 and a cutter blade 64. As shown in FIG. 7B, the film F is cut by the cutter blade 64 after the pressing plates 63, 63 hold the film F between the substantially “U” -shaped chopping base 62.

  As shown in FIG. 6A, each of the transport belts 3 and 3 includes a set of a lower drive belt 31, an upper driven belt 32, and an introduction belt 33. The introduction belt 33 is provided at the upstream end of the upper driven belt 32, and is driven to open and close as indicated by a broken line and a solid line. That is, the introduction belt 33 sandwiches the film F fed from below by the film transfer means 5 between the upstream end 34 of the lower drive belt 31 and holds the film F with the lower drive belt 31 and the upper driven belt. Lead to 32.

Unwinding device 7:
The film roll Fr can be pulled out as will be described below by an unwinding device 7 shown in FIG. The unwinding device 7 is a device for facilitating the rotation of the film roll Fr when the film F is pulled out, and is provided as a pair on the left and right. In the following description, the right unwinding device 7 will be described as an example.

  As shown in FIG. 8, the unwinding device 7 rotates the unwinding roller 70 loaded with the film roll Fr in the unwinding direction (counterclockwise in FIG. 8), and includes a drive shaft 74 and a motor 78. It has. Belts 72 and 77 are bridged between the unwinding roller 70 and the drive shaft 74, and between the drive shaft 74 and the output shaft 75 of the motor 78, respectively. The unwinding roller 70 is rotated via the drive shaft 74 by the rotation.

  The peripheral speed of the film roll Fr by the rotational force of the motor 78 is set to be always smaller than the drawing speed of the film F by the conveyor belts 3 and 3 (FIG. 4). For example, the peripheral speed of the film roll Fr is set to a value slightly smaller than the drawing speed of the film F when the film roll Fr has the maximum diameter.

As shown in FIG. 9, the drive shaft 74 is provided with a brake 85 and a one-way clutch 86.
The one-way clutch 86 is composed of, for example, a free wheel using a ratchet, and transmits the rotation only in the unwinding direction of the drive shaft 74 in FIG. The one-way clutch 86 is set so as to allow the unwinding roller 70 to rotate in the direction in which the film F is pulled out from the film roll Fr and to prevent the unwinding roller 70 from rotating in the opposite direction.

The brake 85 shown in FIG. 9 is formed of an electromagnetic brake, for example, and prevents the unwinding roller 70 from rotating due to inertia.
The drive shaft 74 is provided with a rotation speed detector (rotary encoder) 80 for detecting the rotation of the drive shaft 74. Based on the rotation signal from the rotation speed detector 80, the circumference of the film roll Fr is determined. Speed is controlled.

  Each of the above-described means and devices are controlled by control means (not shown) including, for example, a motor driver (drive circuit) and a microcomputer. The control means controls the speed of the conveyor belts 3 and 3 as described later by controlling the voltage of a known servo motor or the like.

Supply method of film F:
Next, a method for supplying the film F will be described with reference to the timing charts of FIGS.
FIG. 10A shows the supply timing of the conventional film F. FIG.
As shown to Fig.10 (a), the film F is conveyed to the predetermined position of the packaging station S through the 1st-3rd period.

In the first period of FIG. 10A, the film F is pulled out from the film roll Fr by a predetermined length at a constant speed, and then the film feeding is temporarily stopped.
That is, in the first period, the film passing means 5 in FIG. 6A rises from the retracted end position P1 to the entry end position P2 shown in FIG. 6B, and between the introduction belt 33 and the upstream end 34. Insert the front end F2 of the film F into.

  After the insertion, as shown in FIG. 7A, the introduction belt 33 is closed, and the leading end F2 of the film F is sandwiched between the lower drive belt 31 and the introduction belt 33. As a result, the film F is pulled out from the film roll Fr by the belts 31, 32, 33 by a predetermined length (close to the film length and slightly shorter than the film length). On the other hand, the film transfer means 5 descends to the retracted end position P1 and stops.

After the first period shown in FIG. 10A, the film F is cut in the second period.
That is, after the film F is clamped between the pressing plates 63 and 63 shown in FIG. 7B between the upper and lower protrusions of the chopping base 62, the film F is cut by the forward movement of the cutter blade 64. .

  Thereafter, in the third period of FIG. 10A, the cut film F is transferred by the transfer belts 3 and 3 of FIG. 4, and the cut film F is transferred to a predetermined position of the packaging station S. Is done.

  In such a conventional supply cutting method, the film feeding is stopped before the second period. When the film feed is suddenly stopped, the film roll Fr rotates due to inertia, and the film F is loosened as shown by a two-dot chain line in FIG. For this reason, as shown in FIG. 10B, the film F between the chopping base 62 and the presser plates 63, 63, that is, the cut portion of the film F is loosened, so that the film F cannot be cut linearly.

In order to deal with such a problem, the packaging device controls each device at the timing shown in FIG.
That is, in the first period, the film F is first drawn at the high-speed first speed V1, and then decelerated to the low-speed second speed V2 that is slower than the first speed V1. In the second period, cutting is performed while the film F is being pulled out at the second speed V2. Thereafter, in the third period, the cut film F is conveyed at the first speed V1 that is higher than the second speed V2 in the second period.

  Thus, since the film F is pulled out by the transport belts 3 and 3 during the second period, that is, the film feeding is not stopped, the film F can be prevented from being loosened. Therefore, since the film F between the chopping base 62 and the pressing plates 63 and 63 in FIG. 7 does not loosen, the film F can be cut linearly.

In the case of the present embodiment, the brake 85 is operated in accordance with the withdrawal of the film F, and the rotation of the film roll Fr is decelerated and then stopped.
For example, as shown in FIG. 11A, when the rotation of the film roll Fr is completely stopped by operating the brake 85 (FIG. 9) at the start of deceleration from the first speed V1, FIG. As shown in (b), a large tension is applied to the film F, resulting in resistance to pull out the film. Therefore, since the film F is inadvertently stretched, the variation in the cut length (film length) of the film is increased, and the accuracy of the supply position of the film F is also reduced.

  On the other hand, as shown in FIG. 11 (c), when the film roll Fr is decelerated to the second speed V2 and then decelerated using the brake 85 and then stopped substantially simultaneously with the cutting, the film roll In some cases, the stop of Fr is not in time, and the film roll Fr may overrun so as to wind the film F as shown in FIG. In such a case, the film F may be broken by tension.

  Therefore, as shown in FIG. 11 (e), the film feeding speed is adjusted to the second speed V2 while being decelerated from the first speed V1 to a short time (for example, about 50 mm / sec). The brake 85 is turned on, and the rotation speed is temporarily reduced without substantially stopping the rotation of the film roll Fr. Thereafter, the brake 85 is turned off, the film F is cut, and simultaneously the brake 85 is turned on again to stop the rotation of the film roll Fr. That is, the rotation of the unwinding roller 70 is temporarily decelerated between the high speed conveyance (first speed V1) in the first period and the cutting.

  Thus, by performing the operation of the brake 85 in two steps, the rotation of the film roll Fr can be decelerated in accordance with the change in the film drawing speed. Therefore, since no load is applied to the film, the accuracy of the film supply position and the accuracy of the cut length can be stabilized.

FIG. 12 shows a more preferable example.
In the example shown in FIG. 12, at the end of the first period, the drawing of the film F is temporarily stopped from the high-speed first speed V1 (minute time). On the other hand, at the end of the first period, the brake 85 is operated for a short time at the timing when the drawing of the film is temporarily stopped to stop the rotation of the film roll Fr, and then the brake 85 is turned off.
Thereafter, in the second period, the film F is cut by the cutter 61 while being pulled out at the second low speed V2. On the other hand, the brake 85 operates again when the film F is cut, and stops the rotation of the film roll Fr. Thereafter, in the third period, the cut film F is conveyed at a high first speed V1.

  Thus, by temporarily stopping the drawing of the film at the end of the first period, it becomes easy to control the drawing length of the film in the first period and improve the accuracy of the film length.

By the way, as described above, as shown in FIG. 3, the pair of left and right folding plates 204, 204, the rear folding plate 205, the round bar-shaped front folding member 206, and the pusher 207 (FIG. 2) The left and right side edges are folded and packaged on the bottom side of the tray T.
At the time of such packaging, the rear folding plate 205 draws the rear film F so that the film F covers the post 210 shown in FIG. Therefore, the film F may be caught by the post 210 at the rear end (the rear folding plate 205 side) and may be broken.

  Therefore, in this packaging apparatus, a guide plate 90 is attached to the rear end of the post 210 as shown in FIG. By attaching the guide plate 90, the film F drawn by the rear folding plate 205 is not entangled with the post 210, and the film F can be smoothly folded along the guide plate 90.

As described above, the preferred embodiments have been described with reference to the drawings. However, those skilled in the art will readily understand various changes and modifications within the obvious scope by looking at the present specification.
For example, as a packaging device, in addition to a packaging device that discharges a packaged product from the front side, a type that discharges a packaged product to the back may be used.
Further, in addition to the above-described folding type packaging apparatus, the present invention can be similarly applied to a so-called top seal type packaging apparatus.
Moreover, when controlling the rotation speed of the unwinding roller according to the winding diameter of the film roll, it is not necessary to provide the brake.
Accordingly, such changes and modifications are to be construed as within the scope of the present invention as defined by the claims.

  INDUSTRIAL APPLICABILITY The present invention can be used for a packaging device that wraps an article to be packaged using a film drawn from a film roll.

It is a schematic perspective view of the packaging apparatus concerning one Example of this invention. It is a schematic side view which shows a packaging mechanism. It is a perspective view which shows the folding operation of a film. It is a schematic sectional drawing which shows the supply mechanism of a film. It is a front view which shows the delivery means of a film. It is a front view which shows the delivery operation | movement of a film. It is a front view which shows the cutting operation of a film. It is a front view which shows an unwinding apparatus. It is a side view which shows an unwinding apparatus. (A) is the time chart which shows the conventional film supply method, (b) is the front view of the principal part which shows the mode at the time of the conventional film cutting, (c) is the time chart which shows the film supply method of this packaging apparatus It is. It is the time chart which shows the other example of the supply method of a film, and the front view of the principal part which shows the mode of film supply. It is a time chart which shows the further another example of the supply method of a film. It is a fragmentary perspective view which shows the post | mailbox etc. at the time of folding of a film.

Explanation of symbols

3: Conveying belt (conveying means)
61: Cutter 70: Unwinding roller 78: Motor F: Film Fr: Film roll S: Packaging station (packaging section)

Claims (3)

A packaging device that draws a film from a film roll, conveys it to a packaging unit, and covers and wraps the upper surface of the article to be packaged with the film in the packaging unit,
A conveying means for pulling out the film from the film roll and conveying the film toward the packaging unit;
A cutter for cutting the film drawn from the film roll;
A first period in which the film is pulled out from the film roll by a predetermined length; a second period in which the film is cut while the film is further pulled out after the first period; and During the third period during which the film is conveyed to a position, the operations of the conveying means and the cutter are controlled so that the speed of the film during the second period is smaller than the speed of the film during the first period. Control means for controlling the drive;
An unwinding roller loaded with the film roll and driven to rotate by a motor;
A packaging device that is controlled by the control means so as to temporarily decelerate the rotation of the unwinding roller between the high-speed conveyance and the cutting in the first period. 2. The packaging apparatus according to claim 1 , wherein the control means controls the driving of the conveying means so that the speed of the film in the third period is higher than the speed of the film in the second period. 3. The packaging apparatus according to claim 1 or 2 , wherein the control means temporarily stops driving the conveying means at the end of the first period.

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