JP4175496B2 - Equipment for manufacturing synthetic resin square bottom bags - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
TECHNICAL FIELD The present invention relates to a synthetic resin square bottom bag manufacturing method for manufacturing a square bottom bag having a square bottom from a flat bag having one open and the other bottom closed.
[0002]
[Prior art]
Bags using synthetic resins such as polyethylene have been used in various fields. These bags are manufactured by unwinding a coil made of a thin synthetic resin sheet formed into a tube shape or a folded material, and feeding the material to the production line, where it is welded and cut by a thermal welding / cutting device. The process is generally adopted.
[0003]
This manufacturing method is limited to the simplest form of a bag called a “flat bag” in which one is open and the other bottom is closed.
[0004]
[Problems to be solved by the invention]
The flat bag manufacturing method described above cannot be applied to the manufacturing of a square bottom bag that requires a folding step to make the bottom square. For this reason, the square bottom bag had to be relied upon manually. Manufacture of a square bottom bag by hand has a problem that there is a limit to improvement in productivity and there is a variation in quality of the product itself due to individual differences.
[0005]
Accordingly, the present invention provides a method and an apparatus for manufacturing a square bottom bag that enables efficient production of the square bottom bag and has no variation in quality.
[0006]
[Means for Solving the Problems]
The apparatus for producing a square bottom bag made of synthetic resin according to the present invention is a flat bag which is sent while expanding the opening of a flat bag, one of which is open and the other bottom is closed by a welding wire in the width direction, and is set to the shaping arm of the next process The setting device and the shaping that operates from a tapered state to a parallel or divergent state, in which the flat bag set by the flat bag setting device is expanded in a box shape from the inside to the outside and the bottom surface is shaped into a rectangular square bottom. An arm, and a welding / cutting device that welds each ear at an arbitrary position parallel to the bottom of the isosceles triangle ear formed on both sides of the square base shaped by the shaping arm and cuts off the excess ear , the tip of the cylinder of the piston rod, the piston moves forward by forward movement of the rod pushes the portion of the weld line of the bottom portion inside, the fixed pawl is connected with the tip and tapered, the fixing claw Advancing the clamping free pair of movable pawls square bottom bag which has been shaped by the shaping arms open by a hinge mechanism at the same time the fixed claw by advancement of the piston rod is connected in a freely opened and closed proximal end of the fixed pawl and the movable pawl the biased to a pair of direction to close the movable claw between said spring fixing claws by retraction of the piston rod restrains the lower end of the square bottom bag by closing the movable claw which is biased to close by the backward direction is provided And a square bottom bag take-out device.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a longitudinal sectional view showing an outline of a synthetic resin square bottom bag manufacturing apparatus according to the present invention, FIG. 2 is a view showing the operation of a shaping arm, FIG. 3 is a sectional view of a welding / cutting device, and FIG. It is a figure which shows the change of a form.
[0009]
In FIG. 1, a coiler 1 wound with a tube-shaped material A formed of a synthetic resin sheet is disposed, and the material A is placed on the production line by a pair of feed rolls 2 disposed above and below the pass line downstream of the coiler 1. It is sent.
[0010]
A welding device 3 that welds and stitches the raw material A is disposed downstream of the feed roll 2. After welding in the width direction, the raw material A is supplied from the downstream feed roll 4 to the forming device 5. The welding device 3 is provided with a heating head 3a and a base 3b on the upper and lower sides of the pass line. The material A is welded and bag-bound by raising and lowering the heating head 3a. The material that has been bound into a flat bottom is sent to the molding device 5.
[0011]
The forming device 5 includes a cutter 6 on the downstream side of the feed roll 4, and the cutter 6 is arranged above and below the pass line, and is lifted by a lifting device (not shown) to cut the immediate rear side of the welding wire. Then, a flat bag a shown in FIG. 4A is formed in which one side is open and the other side is closed.
[0012]
Note that the flat bag is not limited to the one manufactured from the tube-shaped material, but may be a flat bag in which a folded material is welded on both sides in the width direction and one side is opened and the other folded part is closed. . In the description of this embodiment, a flat bag manufactured from a tube-shaped material will be described.
[0013]
Each flat bag a is set on a shaping arm 8 that rotates integrally with the rotary shaft 7 and shaped.
[0014]
On the cutter side of the forming device 5, a flat bag setting device 9 for expanding the flat bag a and setting it on the shaping arm 8 is provided. The flat bag setting device 9 is provided with a suction pad 9c at the tip of the piston rod 9b of the cylinder 9a, and when the piston rod 9b is retracted, the suction pad 9c sucks the tip (opening side) of the flat bag a. To do. Further, since the stroke direction of the piston rod 9b is inclined toward the end with respect to the pass line, the sucked flat bag a is sent while the opening portion is expanded as shown in the figure, and the shaping arm 8 is moved to the flat bag a. The flat bag a is set on the shaping arm 8.
[0015]
Although the efficiency of setting the flat bag on the shaping arm 8 is reduced, the flat bag may be set one by one while manually expanding the opening portion of the flat bag.
[0016]
The rotating shaft 7 of the molding device 5 is intermittently rotated by an external driving device (not shown), and the flat bag a is shaped one bag at a time by the shaping arm 8. A plurality of shaping arms 8 are arranged in order to expand both sides of the flat bag a in a later step.
[0017]
As shown in FIG. 2, the pair of shaping arms 8 is connected to a fixed arm 7 a provided on the rotating shaft 7 so that the shaping arms 8 are rotatable by a hinge 7 b. The base end portion of the facing shaping arm 8 is rotatably connected to the connecting rod 8a, and the connecting rod 8a is connected so as to open from the state where the tips of the pair of shaping arms 8 are closed in a tapered shape. Moreover, the cylinder 10 is provided in the rotating shaft 7, The piston rod 10a is rotatably connected with the connection rod 8a.
[0018]
Accordingly, when the forming cylinder 10 is operated to advance the piston rod 10a, the shaping arm 8 expands as shown in FIG. 2A, and when the shaping rod 8 moves backward, the shaping arm 8 closes as shown in FIG. 2B. It becomes like this. By moving the piston rod 10a forward so that the pair of shaping arms 8 are parallel or slightly wider than parallel, the flat bag a is formed into a box shape as shown in FIG. It becomes possible to shape the bottom surface (welding wire 20 side) of the material into a quadrangular shape. If the flat bag a is shaped like a box, the isosceles ears 22 are formed on both sides of the quadrangle that forms the square bottom 21.
[0019]
Further, after forming the flat bag a into a box shape, the forming device 5 welds the ear 22 at an arbitrary position in parallel with the bottom 24 of the isosceles ear 22 formed on both sides of the quadrangle and an extra portion. In order to cut off the ear 22, a welding / cutting device 11 is provided. By changing the welding position of the ear 22, the width of the square bottom 21 can be changed. As shown in FIG. 3, the welding / cutting device 11 includes a base pad 11b that is moved up and down by a cylinder 11a and a pair of heating heads 11c. The heating head 11c reciprocates in the direction of the arrow in conjunction with the operation of the base pad 11b by a cylinder device or the like (not shown) to weld a predetermined position of the ear 22 and cut off the excess ear of the flat bag a.
[0020]
Further, a square bottom bag take-out device 12 for taking out the molded square bottom bag b from the shaping arm 8 is disposed at a position where the rotary shaft 7 is rotated 180 degrees clockwise from the material A carry-in side. In the square bottom bag take-out device 12, a fixed claw 12c and a pair of movable claws 12d are connected to the tip of a piston rod 12b of a cylinder 12a. Fixing claw 12b is obtained by the tip and the tapered shape, and connected to freely open and close the hinge Organization to thus movable claw 12d at its proximal end. A spring 12e is provided between the fixed claw 12c and the movable claw 12d, and urges the movable claw 12d in the closing direction. The square bottom bag may be taken out manually.
[0021]
In the above configuration, the process of forming the material into a square-bottom bag is as follows.
First, the tube-shaped raw material A wound around the coiler 1 is supplied to the pass line by the rotation of the feed roll 2, and the full length in the width direction is welded by the welding device 3 to be bag-bound.
[0022]
On the other hand, the leading end portion of the material A reaches the shaping arm 8 portion, the upper and lower surfaces are adsorbed by the suction pad 9b of the piston rod 9a that is retracted, and advances while expanding the leading end side of the material A by the advancement of the piston rod 9a. Let When the welded portion advances along the pass line and slightly passes the cutter 6 portion, the piston rod 9a temporarily stops and simultaneously the cutter 6 moves up and down to cut the material A along the weld line. As a result, the material A becomes a flat bag a having one end opened and the other end bound as shown in FIG. After being cut by the cutter 6, the suction of the suction pad 9 b is released and the flat bag a is set on the shaping arm 8.
[0023]
Next, the rotary shaft 7 rotates 90 degrees, and subsequently or simultaneously with the rotation, the cylinder 10 operates to extend the piston rod 10a. By this movement of the piston rod 10a, the shaping arm 8 which has been in a tapered state is expanded through the connecting rod 8a, and the flat bag a which has wrapped the shaping arm 8 is deformed into a box shape. That is, since the shaping arm 8 expands in a box shape as shown in FIG. 4B, the flat bag a is shaped so as to have a cross section along the outline of the shaping arm 8. FIG. 4B shows a state after the flat bag a is shaped by the shaping arm 8. The welding wire 20 runs on the bottom, and isosceles ears 21 protrude from the left and right.
[0024]
After the flat bag is formed into a box shape by the shaping arm 8, as shown in FIG. 3, the ear 22 is welded at a predetermined position parallel to the base 24 by the operation of the heating head 11c of the welding / cutting device 11, and the extra ear 22 is cut off and removed, and formed into a box-shaped square bottom bag b as shown in FIG. Thereafter, the rotating shaft 7 further rotates 90 degrees in FIG. 1, and the square bottom bag a moves to the collection cylinder 12 side. At this time, the piston rod 10a of the forming cylinder 10 is retracted, and the shaping arm 8 is closed.
[0025]
Then, the piston rod 12b moves forward so that the fixed claw 12c pushes in the welding wire 20 portion, and this portion is bent inward. At the same time, the movable claw 12d sandwiches the upper and lower flat bags a of the shaping arm 8. Become. Thereafter, when the piston rod 12b is retracted, the lower end of the square bottom bag is restrained by the movable claw 12d biased in the closing direction by the spring 12e, and the square bottom bag can be pulled out from the shaping arm 8 and taken out. After this removal, the flat bag a is discharged out of the line and sent to the subsequent line.
[0026]
In the above operation, the flat bags a can be sequentially supplied to the four shaping arms 8 by 90-degree intermittent rotation of the rotating shaft 7 to continuously form the bags.
[0027]
As described above, the material A supplied from the coiler 1 can be extracted while being folded after the steps of welding, cutting, box shaping and welding, and ear cutting. For this reason, everything from the supply of the raw material A to the collection of the product can be performed automatically, and production and quality can be improved. In addition, by arranging the square bottom bag take-out device 12, the bottom of the molded square bottom bag can be removed while being folded, so that not only molding but also the transition to the subsequent process can be performed quickly, and productivity is greatly improved. To do.
[0028]
If the shaping arm 8 is detachable from the molding cylinder 10, shaping arms 8 having various widths can be incorporated into the line. For this reason, even if the specification of the bag is changed, it is not necessary to prepare another line, which is advantageous in terms of equipment costs.
[0029]
In this embodiment, the molding apparatus is rotated in the vertical plane, but may be rotated in the horizontal plane. In addition, multiple square bottom shaping devices are placed on an endless conveyor at intervals, and while rotating the conveyor, a flat bag is set on the square bottom shaping device, and the square bottom is shaped while expanding the open portion of the flat bag. It is also possible to adopt a structure in which a plurality of square bottom shaping devices are arranged on a turntable, or a structure in which the movement of the square bottom shaping device is reciprocated between a flat bag setting device and a taking-out device.
[0030]
【The invention's effect】
In the present invention, since the flat bag is expanded and shaped in a box shape and the square bottom is formed by welding, the square bottom bag can be automatically manufactured, and productivity can be improved. The shaping arm that opens and closes makes it easy to set a flat bag, shape the square bottom, weld and cut the ear, and take out the square bottom bag, and can be automated.
[0031]
Further, since the square bottom bag is taken out while being folded, the transition to the subsequent line is also simplified. In addition, since the material is formed by the shaping arm, it is possible to manufacture a uniform product and improve quality.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing an outline of a bag manufacturing apparatus according to the present invention.
2 is a schematic cross-sectional view taken along line AA in FIG.
FIG. 3 is an explanatory view showing a bag forming process.
FIG. 4 is a diagram showing changes in the form of a bag in the present invention.
[Explanation of symbols]
1: Coiler 2: Feeding roll 3: Welding device 3a: Heating head 3b: Base 4: Feeding roll 5: Forming device 6: Cutter 7: Rotating shaft 7a: Fixed arm 7b: Hinge 8: Shaping arm 8a: Connecting rod 9: Flat bag setting device 9a: Cylinder 9b: Piston rod 9c: Suction pad 10: Cylinder 11: Welding / cutting device 11a: Cylinder 11b: Base pad 11c: Heating head 12: Square bottom bag take-out device 12a: Cylinder 12b: Piston rod 12c : Fixed claw 12d: Movable claw 12e: Spring 20: Welding wire 21: Square bottom 22: Ear 23: Side 24: Bottom A: Material a: Flat bag b: Square bottom bag

Claims (1)

A flat bag setting device that sends while expanding the opening of a flat bag, one of which is open and the other bottom is closed by a welding line in the width direction,
Expanding the flat bag set by the flat bag setting device in a box shape from the inside to the outside and shaping the bottom surface into a rectangular square bottom, the shaping arm operating from a tapered state to a parallel or divergent state;
A welding / cutting device that welds each ear at an arbitrary position parallel to the bottom of the isosceles triangle formed on both sides of the square base shaped by the shaping arm, and cuts off the excess ear;
The tip of the cylinder of the piston rod, the piston moves forward by forward movement of the rod pushes the portion of the weld line of the bottom portion inside, the fixed pawl is connected with the tip and the tapered piston to the proximal end of the fixed claw advancing the clamping free pair of movable pawls square bottom bag which has been shaped by the shaping arms open by a hinge mechanism at the same time the fixed claw by advancement of the rod is connected openably said pair of between a fixed claw and a movable claw square bottom biased in a direction to close the movable claw, to restrain the lower end of the square bottom bag closed biased movable claw is fixed claws to close retracted direction by retraction of the piston rod spring is provided A synthetic resin square bottom bag manufacturing apparatus comprising a bag take-out device.

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