JPH0536294B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method and apparatus for attaching bags to boxes.

(Prior Art) At collection and delivery centers such as consumer cooperatives, food is packed in styrofoam boxes, delivered to the stores and customers mentioned above, and the boxes are collected and reused. Usually, food is packed after a plastic bag is attached to the box. This prevents the inner surface of the box from getting dirty, and also allows the store or customer to take out the food in its bag and hand it to them, and then collect the box on the spot.

The bag was attached manually. First, as shown in FIG. 4, the closed end 5b of the bag 5 is pushed into the box 1. Next, as shown in Figure 5,
The opening edge 5a of the bag 5 is folded back to the outside and attached to the outer periphery of the box 1. Finally, as shown in FIG. 6, the bag 5 is attached to the inner surface of the box 1. Note that the opening edge 5a of the bag 5 is folded back to the outside of the box 1 to prevent the opening edge 5a from being drawn into the inside of the box and being incompletely attached during food packing work. It's for a reason.

(Problems to be Solved by the Invention) In the above method, the work of folding back the opening edge 5a of the bag 5 to the outside of the box 1 requires skill and is time-consuming. Furthermore, although the opening area of the bag 5 is slightly larger than the area of the planar shape of the box 1, since the bag 5 needs to be tightly attached to the box 1, there is not much play. This made it more difficult to fold back the portion 5a.

(Means for Solving the Problems) The present invention has been made to solve the above problems, and the gist thereof is to provide a method for attaching a film-like bag to a box with an open top. lowering the bag relative to the box until it reaches the top of the box, gradually expanding the opening edge of the bag at least halfway through this lowering process, and in the process of simultaneously lowering and expanding the bag. By blowing air downward into the bag, the bag is initially placed against a part of the inner surface of the bottom of the box, and while the air in the internal space of the box is expelled through the bag, the contact area between the bag and the bottom of the box is gradually increased. The bag is folded back to the outside of the box by increasing the size of the bag, finally aligning the bag with almost the entire area of the inner surface of the bottom of the box and the inner surface of the side wall of the box, and further lowering the opening edge of the bag relatively. It's in the installation method.

Another gist of the present invention is a bag mounting device for mounting a bag on a box with an open top, which is characterized by having the following configuration.

(a) A feeding mechanism that supplies a film-like bag folded flat to the top of the box with its opening edge facing down. (b) A suction device is used to suction the opening edge of the bag from both sides. Expansion mechanism (c) for expanding four endless stripes; a guide for forming an inclined part and a vertical part in each endless strip by guiding the middle part of each endless strip to form a dogleg shape; at least one gripping tool attached to each endless strip for gripping the opening edge of the bag expanded by the expanding mechanism, and when the gripping tool is on the slope of the endless strip, the bag is lowered while expanding the opening edge of the bag, and when it is in the vertical part of the endless strip, only the opening edge of the bag is lowered, and the opening edge of the bag is lowered to the position of the outer periphery of the box. lowering mechanism (d), which is arranged above the expanding mechanism, and blows air downward into the bag whose opening edge is gripped by a gripper during the process of simultaneously lowering and expanding the opening edge. An air jet nozzle for attaching a bag to the inner surface of a box (embodiment) An embodiment of the present invention will be described below with reference to FIGS. 1 to 3. Reference numeral 10 in FIG. 1 indicates a conveyor for conveying boxes 1 made of styrofoam, for example.
A pair of guard rails 12 are provided on the frame 11, and a chain 14 with rollers 13 runs along the guide rails 12.

A bag mounting device 20 is arranged in the middle of the conveyor 10. The bag mounting device 20 includes a supply mechanism 30 that supplies a plastic bag 5 in a flat folded state with its opening edge 5a facing down, and a supply mechanism 30 that feeds the opened edge 5a of the folded bag 5 from both sides. An expanding mechanism 40 that expands the bag 5, a lowering mechanism 60 that grips the opening edge 5a of the bag 5 expanded by the expanding mechanism 40 and lowers it to the outer circumference of the box 1 while further expanding the bag. 5 and an air jet nozzle 80 for blowing air into the air.

The supply mechanism 30 is arranged above the conveyor 10. 31 in the figure is a guide roller,
A vinyl film 6 pulled out from a film roll (not shown) is stretched downward around the guide roller 31 . The film 6 is long and cylindrical, and is folded and rolled to form the film roll. Perforations are made in the film 6 in advance, and one side of the perforations (the lower side when hanging down from the guide roll 31) is welded along the perforations. This welded part is the closed end 5 of the bag 5.
It becomes b. In addition, in this specification, not only the bag 5 which is separated from the film 6 and becomes independent, but also the part near the tip that is connected to other parts of the film 6 through the perforations of the film 6 (independent part by cutting) are used. The part scheduled to become bag 5) is also recognized as a bag,
In the figure, reference numeral 5 is given.

A pair of feed rollers 32 that are in contact with each other are arranged below the guide roller 31 . The feed roller 32 has an axis parallel to the conveyance direction of the conveyor 10 and is located directly above the center of the conveyor 10 . These feed rollers 32
It rotates intermittently in the direction indicated by the arrow in the figure.

A pair of auxiliary rollers 33 are arranged directly below the feed roller 32, and these rollers 32,
A plurality of ropes 34 are strung around the rope 33. An annular groove is formed in the feed roller 32 so that the rope 34 can be stored therein.
We ensure mutual contact. A pair of auxiliary rollers 3
A gap is formed between the three. Note that, for convenience of the drawing, the distance between the rollers 32 and 33 is shown shortened compared to other parts. A pedestal 35 and a pressing member 36 that moves toward and away from the pedestal 35 are arranged between the feed roller 32 and the auxiliary roller 33.

The expansion mechanism 40 is arranged below the auxiliary roller 32. This expanding mechanism 40 includes a pair of shafts 41 that are parallel to the conveying direction of the conveyor 10.
have. As shown in FIG. 2, each shaft 41 supports three bell cranks 42. Each bell crank 42 has a cylindrical portion 42c located at a bent portion, one link portion 42a extending outward from the cylindrical portion 42c, and two link portions 42b extending inward from the cylindrical portion 42c. ing. Note that among the three bell cranks 42, the cylindrical portion 42c of one bell crank 42 is fixed to the shaft 41, and the cylindrical portions 42c of the other bell cranks 42 are simply inserted through the shaft 41, but each All the bell cranks 42 are made to interlock with the shaft 41 by a connecting rod 43 passed through the tip of one link portion 42a of the bell cranks 42. Between the tips of the two link parts 42b of each bell crank 42, the upper part of the support base 45 is rotatably supported.

As shown in FIG. 1, a subshaft 46 is arranged directly below each shaft 41, and a link 47 is rotatably supported by the subshaft 46. At the tip of this link 47, the lower part of the upper air support stand 45 is rotatably supported. Upper air link part 42b, link 47 and support stand 45
A parallel link mechanism is constructed.

A hollow suction device 49 is supported on the support base 45 via a spring 48 . A large number of small suction holes are formed in the mutually opposing vertical surfaces of the adsorbers 49, which are arranged three on each side like upper air. Then, by operating a vacuum suction machine (not shown) to create a negative pressure in the chamber and performing suction through the suction hole, the opening edge 5a of the bag 5 can be suctioned onto a vertical surface.

One end of a swinging link 50 is rotatably connected to the middle part of the link portion 42a of one of the bell cranks 42 on the right side in FIG.
The other end of the disk 51 is rotatably supported at a location offset from the center of a disk 51 that is rotated by a motor. Gears 52 and 53 that mesh with each other are fixed to the pair of shafts 41.

As shown in FIG. 1, lowering mechanisms 60 are arranged on both sides of the conveyor 10. To be more specific, there is a drive shaft 6 diagonally below the conveyor 10.
1 is arranged, and two shafts 62 and 63 are arranged above this driving shaft 61. A pair of sprockets 64 spaced apart from each other are fixed to the driving shaft 61, and a pair of sprockets 65, 66 are rotatably supported at both ends of the shafts 62, 63, respectively. A pair of sprockets 67 are rotatably supported on the sprocket 41. In addition, a dog-shaped guide 68 is provided diagonally below the sprocket 65.
is located. Each set of sprockets 64-6
7 and the guide 68, a chain 69 (endless strip) is spanned.

The chain 69 runs as shown by the arrow in FIG.
(Hereinafter, this part will be referred to as the first part)
The vertical portion 69a) is inclined between the sprocket 65 and the guide 68 (hereinafter this portion is referred to as the inclined portion 69b), and becomes vertical again between the guide 68 and the sprocket 64 (hereinafter this portion is referred to as the inclined portion 69b). (referred to as a second vertical portion 69c).

A total of four chains 69, two on the left and right, are each provided with two gripping tools 70 for gripping the opening edge 5a of the bag 5. Upper air gripping tool 70
has a receiving plate 71 supported by a chain 69, and a holding pawl 73 and an operating lever 74 rotatably supported by the receiving plate 71 via a hinge 72. The presser pawl 73 and the operating lever 74 are fixed to each other so as to rotate integrally. Further, a reversing spring (not shown) is stretched between the side surfaces of the presser claw 73 and the receiving plate 71, and this reversing spring moves the presser claw 73 in the direction in which it closes against the receiving plate 71 or away from the receiving plate 71. It is biased in the direction of opening.

Strippers 75 are arranged above both sides of the frame 11 of the conveyor 10 between the two chains 69 for removing the opening edge 5a of the bag 5 from the gripper 70. A return member 77 having a cam surface 77a for returning the presser claw 73 to the open state by rotating the operating lever 74 is arranged near the chain 69.

There are 4 rollers between the auxiliary roller 33 and the expanding mechanism 40.
A downward air jet nozzle 80 is arranged. This nozzle 80 is connected to a compressed air source (not shown), and is located inside the box 1 from the center of the conveyor 10 when viewed from above as shown in FIG. is located near.

In the above configuration, the roller 13 of the conveyor 10
The box 1 placed on the bag is stopped by a stopper (not shown) at the position of the bag mounting device 20.

When the feed roller 32 rotates, the film 6 is continuously pulled out from the film roll, and the portion near the tip of the film 6, that is, the bag 5 before separation, hangs down directly above the box 1 while being folded. The opening edge 5a passes between the pair of suction devices 49 of the expansion mechanism 40 and reaches slightly below.

Next, by rotating the disk 51 of the expansion mechanism 40,
When the swing link 50 moves to the left in FIG.
The right bell crank 42 rotates counterclockwise. This rotation of the bell crank 42 is transmitted to the left shaft 41 via the right shaft 41 and gears 52, 53, and the left bell crank 42 rotates clockwise. As a result, the pair of adsorbers 49 rotate downward around each shaft 41 and approach each other. Since the rotation trajectories of the suction devices 49 interfere with each other, the suction devices 49 descend while touching each other while being pressed by the springs 48 from the middle. At this time, the vicinity of the opening edge 5a of the bag 5 is pinched by both adsorbers 49 and pulled down. Before this pulling down, the holding member 36 moves to the pedestal 35 and the film 6 is
Since the film 6 is pressed slightly above the perforation, the film 6 is cut at the perforation by being pulled down by the suction device 49, and a separated bag 5 is obtained.

At the time of the above-mentioned cutting, the separated bag 5 is restricted inside the opposing ropes 34, so that the bag 5 does not tilt significantly to the left or right and cover the nozzle 80 or the like.

When the pair of adsorbers 49 rotate further, they separate from each other. At this time, the suction action of the suction device 49 attracts both sides of the opening edge 5a of the bag and spreads it out.

On the other hand, the lowering mechanism 60 is temporarily stopped, and one gripper 70 attached to each chain 69
is waiting at the first vertical portion 69a of the chain 69 with the holding pawl 73 open. In this standby state, the tip of the actuating lever 74 is located on the movement trajectory of the suction device 49 (indicated by the dashed line), as shown in FIG. When the suction device 49 moves and slightly rotates the operating lever 74, the holding pawl 73 closes due to the action of the reversing spring. At this time, the opening edge 5a, which hangs down slightly below the suction device 49, is held between the pressing claws 73 and the support base 71.

Note that from the time the suction unit 49 starts rotating downward until the opening edge 5a is transferred to the gripper 70,
The disk 51 has rotated 180 degrees, and the next 180 degrees
With this rotation, the swing link 50 moves to the right in the figure. In this process, the adsorber 49 returns to the original position shown in FIG. 1 through the same trajectory as described above.

After the above-mentioned delivery, the driving shaft 61 is driven and the chain 69 starts running. Then, the gripping tool 70 gripping the opening edge 5a first descends vertically and reaches the sprocket 65. In this process, downward injection of air is started from the nozzle 80,
It is blown into bag 5. As a result, the bag 5 is turned over and hangs down from the gripper 70 as shown by the imaginary line A in FIG. 1, and the closed end 5b enters the box 1.

When the gripper 70 passes the sprocket 65,
It reaches the inclined part 69b of the chain 69, and here,
Since the gripping tool 70 moves obliquely downward, the opening edge 5a of the bag 5 descends while being spread out. Air continues to be blown during this process, and when the gripper 70 is near the sprocket 65, the first
As shown by the imaginary line B in the figure, the closed end 5b of the bag 5
is grounded approximately at the center of the bottom 1a of the box 1. In the process of the gripping tool 70 moving diagonally downward, the bag 5 is pressed against the bottom 1a of the box 1 by air pressure and comes into close contact with the bottom 1a of the box 1, as shown by the imaginary line C in FIG. It gradually increases. Furthermore, as shown by the imaginary line D, the bag 5 is located at the bottom 1 of the box 1.
After it comes into close contact with the entire area of side wall 1b, it comes into close contact with the entire area of side wall 1b.

As described above, air is continuously blown in the process of lowering the opening edge 5a, and the bag 5 is moved into the box 1.
Since the bag 5 gradually comes into close contact with the side wall 1b from the center of the bottom 1a of the box 1, the air inside the box 1 is gradually pushed out from between the bag 5 and the side wall 1b of the box 1, and the box 1 This eliminates the inconvenience of the bag 5 not being properly attached due to the pressure of residual air inside the bag 5.
can be reliably attached to the inner surface of the box 1. Moreover, since the opening edge 5a descends while being expanded, a large gap is formed between the bag 5 and the side wall 1b of the box 1 in the initial installation state immediately after the bag 5 touches the bottom 1a of the box 1. Therefore, the air inside the box 1 can be better removed, and the adhesion of the bag 5 to the box 1 can be made more reliable.

When the gripper 70 reaches the vicinity of the bent portion of the guide 68, the close contact of the bag 5 with the box 1 is almost completed.

When the gripping tool 70 passes through the bent part of the guide 68, as shown in FIG. 3, the opening edge 5a of the bag 5
are expanded by the holding claws 73 with almost no loosening, and their cross-sectional shape is slightly larger than the outer shape of the box 1.

Next, the gripper 70 vertically descends at the second vertical portion 69c of the chain 69 and reaches the outer periphery below the upper end of the box 1, whereby the opening edge 5a of the bag 5 is It is folded back to the outside of box 1 as shown.

Next, the gripping tool 70 reaches the same height as the stripper 75, and the opening edge 5a of the bag 5 is locked by the stripper 75 and removed from the gripping tool 70. Almost at the same time as this separation, the air injection from the nozzle 80 is stopped.

Next, after the gripper 70 passes the sprocket 64, it turns upward and stops at a position slightly above the sprocket 64. At this time, the other gripping tool 7
0 is again the first of chain 69 as shown in FIG.
It waits in the vertical section 69a.

In the process of raising the gripper 70, the actuating lever 74
hits the cam surface 77a of the return member 77, and is rotated in the opposite direction to the direction in which the suction device 49 hits, and the holding pawl 73 is returned to the open state by the reversal spring.

After the bag 5 is completely attached to the box 1, the box 1 is released from the stopper, and the box 1 is transported by the conveyor 10 to a destination, that is, a food packing work place.

The present invention is not limited to the above embodiments, and various embodiments are possible. For example, in this example, air is continuously blown for almost the entire time of the lowering process until the opening edge of the bag is separated from the gripping tool, but air is blown continuously from the time when the opening edge of the bag is being expanded. You may do this, or you may do it after the vertical descent process has started after fully opening. Alternatively, the closed end of the bag may be grounded to the bottom of the box when air blowing is started. Furthermore, at the start of this air blowing, the bag may be grounded over a wide area at the bottom of the box. However, even in this case, a sufficient gap is required between the side wall of the box and the bag so that the air inside the box can escape.

Air may be blown intermittently, or may be blown briefly at the end of the downward movement until the opening edge of the bag reaches its upper end.

Furthermore, after the bag is brought into contact with the inner surface of the box by blowing air, the blowing of air may be stopped before the opening edge reaches the top of the box.

By raising the box without moving the opening edge of the bag, the opening edge of the bag may be relatively lowered to the position of the outer periphery of the box.

The opening edge of the bag may be fully opened and then vertically lowered.

The film does not need to have perforations and welded parts formed in advance, but may simply be a cylindrical film that is folded. In this case, a cutting mechanism such as a cutter and a heat welding mechanism are arranged below the feed roller.

(Effects of the Invention) As explained above, according to the method of the present invention, by blowing air into the bag and lowering the opening edge of the bag relative to the box, it is possible to align the bag with the inner surface of the box. You can easily perform folding operations. Moreover, the opening edge is also expanded during the process of lowering the opening edge, and air is blown into the bag during the process of lowering and expanding at the same time. The area of contact between the bag and the bottom of the box is gradually increased while expelling air from the internal space of the box through the bag, and finally the bag is applied to almost the entire inner surface of the bottom of the box and the inner surface of the side wall of the box. Since the bag is attached to the box, it is possible to prevent a large amount of air from remaining between the bag and the box, and the bag can be attached to the box in a good manner.

Further, according to the device of the present invention, the endless strip is bent into a dogleg shape, and in the process of moving the gripper along the slope of the endless strip, the opening edge of the bag is expanded and lowered at the same time. This makes it possible to greatly simplify the configuration for simultaneously performing expansion and lowering.

[Brief explanation of the drawing]

1 to 3 show one embodiment of the present invention, FIG. 1 is a front view of the bag mounting device, FIG. 2 is a plan view showing the expansion mechanism of the bag mounting device, and FIG. 3 is a front view of the bag mounting device. It is a schematic plan view showing a state where the opening edge of the bag is fully opened, and
FIGS. 4 to 6 are cross-sectional views illustrating a conventional bag mounting method step by step. 1...box, 5...bag, 5a...opening edge of bag,
10... Conveyor, 20... Bag mounting device, 30...
... Supply mechanism, 40 ... Expansion mechanism, 49 ... Adsorption device, 60 ... Lowering mechanism, 68 ... Guide, 69 ...
... Endless body (chain), 69b ... Inclined part, 6
9c...Vertical part, 70...Gripper, 80...Air jet nozzle.

Claims (1)

[Claims] 1. A method for attaching a film bag to a box with an open top, in which the opening edge of the bag is lowered relative to the box until it reaches the top of the box, and this lowering process At least in the middle, the opening edge of the bag is gradually expanded, and air is blown downward into the bag in the process of simultaneously lowering and expanding, so that the bag is initially attached to a part of the inner surface of the bottom of the box. The area of contact between the bag and the bottom of the box is gradually increased while expelling air from the interior space of the box through the bag, and finally the bag is attached to almost the entire inner surface of the bottom of the box and the inner surface of the side walls of the box. A bag mounting method characterized by folding the bag to the outside of the box by lowering the opening edge of the bag relatively. 2. The bag mounting method according to claim 1, wherein the air is continuously blown. 3. A bag attaching device for attaching a bag to a box with an open top, characterized by having the following configuration. (a) A feeding mechanism that supplies a film-like bag folded flat to the top of the box with its opening edge facing down. (b) A suction device is used to suction the opening edge of the bag from both sides. Expansion mechanism (c) for expanding four endless stripes; a guide for forming an inclined part and a vertical part in each endless strip by guiding the middle part of each endless strip to form a dogleg shape; at least one gripping tool attached to each endless strip for gripping the opening edge of the bag expanded by the expanding mechanism, and when the gripping tool is on the slope of the endless strip, the bag is lowered while expanding the opening edge of the bag, and when it is in the vertical part of the endless strip, only the opening edge of the bag is lowered, and the opening edge of the bag is lowered to the position of the outer periphery of the box. lowering mechanism (d), which is arranged above the expanding mechanism, and blows air downward into the bag whose opening edge is gripped by a gripper during the process of simultaneously lowering and expanding the opening edge. , an air jet nozzle that attaches the bag to the inside of the box.