JPH0848444A - Tension applying device for film for manufacturing bag - Google Patents

Abstract

PURPOSE:To provide a tension applying device for a film for manufacturing a bag which can apply a specific tension on the film for manufacturing the bag. CONSTITUTION:When the transfer of a film 3 for manufacturing the bag is restarted, a film roller 14 for manufacturing the bag is locked and does not revolve, and the film 3 for manufacturing the bag is sent by the portion laid in a guide roller 5 dancing roller 22 guide rollers 6 and 7. The dancing roller 22 rises, and a swing arm 24 is pulled up, and the brake application for the film roll 14 is released, and then the revolution is started to drive out the film 3. Further, also the shaft insertion supporting part 30 of the swing arm 24 rises, turning a spring installation rod 31, through the insertion of the spring installation rod 31, and the lower end of the coil spring 32 is pushed up and compressed. The pulling-up force of the swing arm 24 due to the springy force and the feed acts in the opposite directions each other, nipping the film 3, and cope with each other, and a specific tension is applied.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tensioning device for a bag-making film.

[0002]

2. Description of the Related Art Usually, a bag-making film is unrolled from a bag-rolling film roll by intermittent feeding and rotated by the unwound tension. Then, even after the bag-making film is stopped by intermittent transfer, since the bag-making film roll rotates by inertia, the dancing roller descends to absorb the looseness of the feeding length portion, and the bag-making film has a predetermined length. Tension is applied.

[0003]

However, even if the dancing roller is lowered to a predetermined lowered position, if the bag-making film roll rotates and the bag-making film continues to be unwound, the unrolling length cannot be absorbed by the dancing roller. There is a problem that due to the slack of the sagging portion, a predetermined tension cannot be applied to the bag-making film when the transfer is restarted, which causes inconvenience in the transfer of the bag-making film. The present invention has been made to solve the above problems, and an object of the present invention is to provide a tension-applying device for a bag-making film, which can give a predetermined tension to the bag-making film.

[0004]

A tensioning device for a bag-making film according to the present invention for achieving the above object is provided between front and rear guide rollers arranged to guide a bag-making film that is intermittently transferred. And a braking mechanism for stopping the rotation of the bag-making film roll, and the dancing roller absorbs the looseness of the delivery length portion of the bag-making film to a predetermined descending position. When descending, the braking mechanism is driven to stop the feeding of the bag-making film, the transfer of the bag-making film is restarted, and the dancing roller is started to rise by the bag-making film, and then, A predetermined tension is applied to the bag-making film without driving the braking mechanism.

[0005]

According to the tension applying device for a bag-making film of the present invention, when the dancing roller is lowered to a predetermined lowered position, the braking mechanism is driven, so that the bag-making film rolls out of the bag-making film roll. The feeding stops. After the transport of the bag-making film is restarted and the dancing roller starts to move upward, the braking mechanism is deactivated and the bag-making film is fed out. Therefore, since a predetermined tension can be applied to the bag-making film to be transferred and no slack is generated, there is an effect that the intermittent transfer of the bag-making film can be stably performed.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the accompanying drawings. In FIG. 1, reference numeral 1 is an automatic bag-making device, and a transfer path 4 for a bag-making film 3 is formed on a frame 2.
In the transfer path 4, a guide roller 5, a pair of guide rollers 6 and 7, an intermittent feeding device 10 including a driven roller 8 and a drive roller 9, and a pair of sealing bars 1 are arranged in this order in the transfer direction.
A fusion-sealing device 12 made up of Nos. 1 and 11 and a cutter 13 for cutting the bag-making film 3 intermittently fed at predetermined intervals are arranged. A pair of loading arms 15 and 15 for rotatably loading a bag-making film roll 14 on which the bag-making film 2 is wound are disposed diagonally below and behind the guide roller 5.

An air cylinder 16 and a brake shoe 17 connected to a piston rod 16a of the air cylinder 16 and swingably supported are provided on one of the loading arms 15 and 15. When the piston rod 16a extends due to the supply of pressure air, the brake shoe 17
Oscillates to press the outer periphery of the braking disc 19 fitted to the cored bar 18 of the bag-making film roll 14 to stop the rotation of the bag-making film roll 14. Further, when the pressurized air is released to the atmosphere, the piston rod 16a contracts by the elastic force of a return spring (not shown), separates the brake shoe 17 from the braking disk 19, and allows the bag-making film roll 14 to rotate.

Tensioning device 2 for bag making film 3
1 is disposed below the transfer path 4. The dancing roller 22 is attached to the tip of a curved rocking arm 24 that is loosely fitted to the rotary shaft 23 so as to move vertically between the guide roller 5 and the pair of guide rollers 6 and 7. The lowermost position of the swing arm 24 is set to be adjustable by a stopper 25 arranged on the frame 2. A valve switching lever 26 that interlocks with the swing arm 24 is loosely fitted to the rotating shaft 23. At the tip of the valve switching lever 26, an arc surface 2 centered on the rotating shaft 23
6a is formed. Further, a rotary lever 27 that pushes up the swing arm 24 is fitted on the rotary shaft 23, and is connected to a push-up air cylinder 28 that is swingably attached to the frame 2.

Further, the swing arm 24 is provided with a roller 29 with which the rotary lever 27 comes into contact and a shaft insertion support portion 30. The shaft insertion support portion 30 is rotatably supported by the swing arm 24, and supports the spring mounting rod 31 which rotatably supports the upper end of the frame 2 through the frame. The coil spring 32 attached to the spring attachment rod 31 has its upper end fixed to the spring attachment rod 31 and its lower end not fixed to the shaft insertion support portion 30.
It is drooping toward. A switching valve 33 is arranged on the frame 2. The switching valve 33
Is pressed against the circular arc surface 26a of the valve switching lever 26 that interlocks with the swing arm 24 while the swing arm 24 is descending from a predetermined lowered position to the lowest position, and an air supply circuit for the air cylinder 16 (not shown). Switch).

The operation of the tension applying device 21 having the above structure will be described below. In the bag-making film 3 guided by the guide roller 5 and the pair of guide rollers 6 and 7, the length of the bag-forming film roll 14 fed out at the previous transfer is lowered by the dancing roller 22. Guide roller 5
→ Dancing roller 22 → Guide rollers 6 and 7 are bridged in this order, and a predetermined tension is applied to the roller, so that no slack occurs. Then, when the swing arm 24 having the dancing roller 22 attached to its tip is lowered to a predetermined lowered position,
The arc surface 26a of the valve switching lever 26 presses the switching valve 33. Therefore, the switching valve 33 is switched, pressurized air is supplied to the air cylinder 16, the piston rod 16a extends, and the film roll 14 for bag making is braked and locked. Even when the swing arm 24 reaches the lowest position, the switching valve 33 is pressed against the arc surface 26a. At this time, the coil spring 32 mounted on the spring mounting rod 31 is in a state of hanging down by its own weight.

A fusion-sealing device 12 arranged at the tip of the transfer path 4.
When the bag-making film 3 is melt-sealed and cut by the cutter 13, the driving roller 9 of the intermittent feeding device 10 is driven to pass the bag-making film 3 between the driving roller 9 and the driven roller 8. The film 3 is sent and the transfer is restarted. At this time, since the bag-making film roll 14 is locked and does not rotate, the bag-making film 3 is not fed out. Therefore, the guide roller 5 → the dancing roller 22
→ Since the bag-making film 3 in the portion where the guide rollers 6 and 7 are bridged in this order is pulled out, the dancing roller 22 is raised accordingly and the swing arm 24 is pulled up.

After the lifting of the swing arm 24 from the lowest position is started, the arc surface 26 of the valve switching lever 26 is started.
When a is disengaged from the switching valve 33 and the pressure is released, the pressure air supplied to the air cylinder 16 is released to the atmosphere, and the piston rod 1 is released by a return spring (not shown).
6a contracts, and the braking of the bag-making film roll 14 is released. During this period, since the bag-making film 3 is continuously transported, the bag-making film roll 14 starts rotating to feed the bag-making film 3. In addition, the shaft insertion support portion 30 of the swing arm 24 also moves through the spring mounting rod 31 while rotating and ascending. Then, the lower end of the coil spring 32 is pushed up and compressed. The spring elasticity due to the contraction and the pulling up force of the swinging arm 24 due to the feeding act in opposite directions with the bag-making film 3 sandwiched therebetween to counteract each other, thereby giving a predetermined tension to the bag-making film 3. (See Figure 2).

When the bag-making film 3 has been transported by a predetermined length and the feeding is interrupted, the spring elasticity of the compressed coil spring 32, the swing arm 24 and the dancing roller 2 are stopped.
The self-weight of 2 acts on the bag-making film 3 between the guide roller 5 and the pair of guide rollers 6 and 7, and pulls down the bag-making film 3 in the length portion fed from the bag-making film roll 14 to loosen it. Absorb. When the valve switching lever 26 of the swing arm 24 acts on the switching valve 33, the bag-making film roll 14 is braked and locked again, and the feeding of the bag-making film 3 is stopped.

In the above-described embodiment, the bag making film roll 14 is forcibly braked by the lowering of the dancing roller 22, so that the bag making film 3 is fed out, becomes lighter, and easily rotates. Even when the amount of the bag-making film 3 delivered from the bag-making film roll 14 increases, a predetermined tension can be applied to the bag-making film 3. The air cylinder 28 includes the loading arm 15,
When the bag-making film 3 is unwound from the bag-making film roll 15 loaded in 15 and the bag-making film 3 is set on the transfer path 4, the rotating lever 27 is brought into contact with the roller 29 and the swing arm 24 is retracted upward. belongs to. Film for bag making 3
At the time of setting, the upper guide roller 6 of the pair of guide rollers 6 and 7 is pulled up to pass the bag-making film 3.

[Brief description of drawings]

FIG. 1 is a partially cutaway side view showing a schematic configuration of the present invention.

FIG. 2 is a side view of an essential part showing a state where a dancing roller is raised.

[Explanation of symbols]

1 → Automatic bag making device 2 → Frame 3 → Bag making film 4 → Transfer path 5, 6, 7 → Guide roller 8 → Following roller 9 → Drive roller 10 → Intermittent feeding device 11 → Welding bar 12 → Welding device 13 → Cutter 14 → Bag Making Film Roll 15 → Filling Arm 16
→ Air cylinder 16a → Piston rod 17 → Brake shoe 18
→ core metal 19 → braking disc 21 → tensioning device 22 → dancing roller 23 → rotating shaft 24 → swing arm 25 → stopper 26 → valve switching lever 26a → circular surface 27 → rotating lever 28 → air cylinder 29 → roller 30 → shaft insertion support 31 → spring mounting rod 32 → coil spring 33 → switch valve

Claims (1)

[Claims] 1. A dancing roller that moves up and down between front and rear guide rollers arranged to guide a bag-making film that is intermittently transferred, and a braking mechanism that stops the rotation of the bag-making film roll. When the dancing roller absorbs the slack in the feeding length portion of the bag-making film and descends to a predetermined lower position, the braking mechanism is driven to stop the feeding of the bag-making film, After the transfer of the bag-making film is restarted and the dancing roller starts to move upward by the bag-making film, the braking mechanism is not driven to apply a predetermined tension to the bag-making film. A film tensioning device.