JPH0223397Y2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field The present invention is directed to a bag making machine in which when the bottom heat-sealing of a polyethylene bag is carried out, the bottom heat-sealed portion of the polyurethane bag that has not yet hardened is removed from the adjacent polyethylene bag. This invention relates to a welding prevention device for the heat-sealed bottom part of a plastic heavy bag to prevent welding to the heavy bag.

PRIOR TECHNOLOGY Generally, as shown in Fig. 1, plastic heavy bags are made by sequentially cutting and heat-welding a long plastic cylinder to the bottom edge 1.
The bottom edge 1 of the next plastic bag is cut and the bottom heat sealed part 2 is formed.
The opening 3 is formed during the formation of the opening 3.

In order to efficiently manufacture such heavy-duty plastic bags while saving work space, the plastic heavy-duty bags manufactured one after another are quickly fed by a fast-feeding conveyor, and then transferred to a subsequent slow-speed conveyor. The bags are stacked on top of each other and transported to the next process.

Problems with the Prior Art However, when the bags are overlapped and transported in this way, the bottom heat-sealed portion 2, which has not yet hardened, is welded to the adjacent plastic bag, causing defects in the plastic bag and resulting in defective products. Various proposals have been made in the past to prevent this, but the structure is complicated and expensive, and the work is troublesome.

Purpose of the invention The present invention eliminates the above-mentioned drawbacks, reliably prevents the bottom heat-sealed part from welding to the adjacent plastic bag, and is easy and inexpensive without making any changes to the existing bag making machine. It is an object of the present invention to provide a device for preventing welding of the bottom heat-sealed part of a heavy-duty polyethylene bag, which can be placed in a plastic bag.

Structure of the invention The above-mentioned object is based on the characteristics of the present invention, and provides a means for sequentially manufacturing heavy-duty plastic bags from a long plastic cylinder by heat welding and heat-cutting, and a speed for rapidly feeding the manufactured heavy-duty plastic bags. In a plastic bag manufacturing apparatus comprising a feeding conveyor and a low-speed conveyor disposed following the fast-feeding conveyor and sequentially overlapping each plastic bag given fast-feeding and transporting the same to the next process, the low-speed The conveyor is arranged close to and parallel to the upper side of the conveyor, and has a swingable separation plate arranged at an interval corresponding to the shift width for sequentially overlapping on the outer surface thereof, and a hanging part on the lower side thereof. is provided with endless belt means configured to run in the same direction and at the same speed as the low-speed conveyor so that the free end of the separation plate of the lower hanging portion is in contact with the low-speed conveyor and moves together with the low-speed conveyor; When the heavy plastic bags are rapidly fed by the fast-feeding conveyor and stacked on the low-speed conveyor one after another, the area of the bottom heat-sealed portion of each heavy-duty plastic bag is sequentially covered by the swingable separating plate. To provide a device for preventing welding of the bottom heat-sealed parts of a plastic bag, which is configured to surely prevent the bottom heat-sealed parts separated from each other and not yet hardened from welding to an adjacent plastic bag. This is achieved by

As configured as described above, the separating plate of the bottom heat sealing part welding prevention device according to the present invention can separate the range of the bottom heat sealing part of the plastic bag from the adjacent plastic bag, Even if the bottom heat-sealed portion is not yet cured, it is possible to avoid welding to the adjacent plastic bag.

Embodiment FIG. 2 shows a rapid-feed plastic bag manufacturing apparatus incorporating the present invention. This device cuts a polycylindrical body that is continuously fed from the right side to form a bottom edge 1, and also forms a bottom heat-sealed part 2 by heat welding, and then forms the bottom heat-sealed part 2 of the next plastic bag. a bottom cutting heat welding section 4 having a cutter and a heat sealing device for forming the opening 3 of the plastic bag by cutting when forming the plastic bag 2, and for providing rapid feeding to the manufactured plastic bag; This rapid-feeding conveyor 5 and this rapid-feeding conveyor 5
It has a continuous feed conveyor 8 which is arranged close to the upper side and has a hanging part 7 which can swing up and down about the shaft 6, and the hanging part 7 is normally separated upward from the rapid feeding conveyor 5. Each time a heavy plastic bag is sent in, the hanging part 7 is swung downward and brought into pressure contact with the fast-feeding conveyor 5, so that fast-feeding is applied to the sandwiched heavy-duty plastic bag. A low-speed conveyor 9 is disposed downstream of the rapid conveyor 5 for gathering the plastic bags and transporting them to the next process after the bottom heat-sealed portion 2 has hardened. The bottoms of the plastic bags are successively stacked on the low-speed conveyor 9 with their positions being shifted very slightly.

Close to the exit side of the low-speed conveyor 9, a leveling roller 10 is arranged to be able to swing up and down for aligning and holding the sequentially stacked plastic bags.

The above structure is conventional and is not directly related to the present invention, so it will not be described in detail.

According to a feature of the present invention, an endless belt 11 is stretched close to and parallel to the upper side of the low-speed conveyor 9 by a pair of pulleys 12 and 13, so that the lower tensioned portion is connected to the low-speed conveyor 9. It is designed to run in the same direction and at the same speed as the upper hanging section.

On the outside of this endless belt 11, a separating plate 14 is swingably supported to maintain an interval corresponding to the width of the shift width in which the plastic bags are stacked one on top of the other on the low-speed conveyor 9 with slight shifts in position. When the endless belt 11 is running, the free end of the separating plate 14 of the lower hanging portion comes into contact with the low speed conveyor 9 and moves together with the low speed conveyor 9, as shown in the figure.

When the endless belt 1 is running, the upper separating plate 1
4 is swung downward at the right end, and a stopper 15 is provided to stop the next separating plate 14 from coming into contact with the low-speed conveyor 9 one by one until a predetermined time.

Therefore, when the plastic bags are sequentially sent onto the low-speed conveyor 9, the bottom heat-sealed portion 2 of the bags is transferred to the third bag.
As shown in the figure, the polyethylene bag hits the separation plate 14 and rides on it, maintains a distance between it and the next separation plate 14, and then the next plastic bag rides on the next separation plate 14. It is reliably separated from the bottom heat-sealed part 2. This state is shown in FIG.

As a result, even if the bottom heat-sealed portion 2 of each plastic bag is not yet cured, it will not contact and weld to an adjacent plastic bag.

Effects of the invention As mentioned above, according to the invention, the low speed conveyor 9
Since the endless belt 11 is provided close to the upper side and parallel to the endless belt 11, and the separation plate 14 is provided on the outside of the endless belt 11, even if the bottom heat-sealed portion 2 of each plastic bag is not yet cured, Separation plate 14
This ensures that the plastic bags are kept separate from the adjacent plastic bags, and will not come into contact with and weld to the next plastic bag. Moreover, since the present invention is placed on the constant speed conveyor of the existing bag making machine and does not require any modification of the equipment, it can be installed very easily and inexpensively, and has excellent advantages such as easy operation. It is.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a polyethylene bag having a heat-sealed bottom part. FIG. 2 is a schematic side view showing a plastic bag manufacturing apparatus incorporating the present invention. FIG. 3 is a side view showing an endless belt provided with a separating plate, which is a feature of the present invention.
FIG. 4 is a schematic side view showing that the region of the bottom heat-sealed portion of the plastic bag is supported and held apart from the adjacent plastic bag by a separating plate. 1...Bottom of the plastic bag, 2...Opening of the plastic bag, 3...Sealant application part of the plastic bag, 4...Heat welding, cutting and sealant application part, 5...Rapid conveyor , 7... Suspension section, 8... Intermittent feed conveyor, 9... Low speed conveyor, 11... Endless belt, 14... Separation plate, 15... Stopper.

Claims (1)

[Scope of utility model registration request] means for sequentially manufacturing heavy poly bags from a long poly cylinder by heat welding and cutting; a fast feed conveyor for rapidly feeding the manufactured heavy plastic bags; disposed following the fast feed conveyor; In a plastic bag manufacturing apparatus comprising a low-speed conveyor that sequentially overlaps each plastic bag given rapid feeding and transfers it to the next process, the plastic bag is placed close to and parallel to the upper side of the low-speed conveyor, and the outer surface The conveyor has swingable separation plates arranged at intervals corresponding to the shift width of the sequentially stacked one and the lower hanging part thereof runs in the same direction and at the same speed as the low-speed conveyor. Endless belt means is provided so that the free end of the separating plate of the lower hanging part moves together with the low-speed conveyor while being in contact with the low-speed conveyor, and the plastic bag is rapidly fed by the high-speed conveyor and When stacked one after another on a low-speed conveyor, the areas of the bottom heat-sealed portions of each plastic bag are successively separated from each other by the swingable separating plate, so that the bottom heat-sealed portions that have not yet hardened are separated from each other by the swingable separating plate. An apparatus for preventing welding of a heat-sealed bottom part of a plastic bag, characterized in that it reliably prevents the bottom part from welding to an adjacent plastic bag.