JPH05278703A - Method for manufacturing, filling and sealing bags - Google Patents

Abstract

PURPOSE: To enable all bags to be filled without useless volume by advancing a tubular film web always to a printed mark at the edge of back opening to sever, followed by adjusting length of a segment forming the bottom joint portion in accordance with a setting based on the filling state. CONSTITUTION: A tubular web 826 has been printed with a format and is severed so as not to pass this print when tube segment is formed. Thus the tubular web 26 is advanced intermittently with the printed mark provided at the opening edge of the bag, and length of the bag segment is changed by the operator between the opening edge of the bag segment and the bottom joint portion of the following bag segment. When cutting to separate it at the opening edge, a knife 834 is applied to the tubular web 26 in the state without the joint flange 33. When this web 26 advances by the length of a severed segment, the knife 34 is again applied to the web 26, but this is conducted with the joint flange 33. Separation of segment in this middle portion and formation of transversal joint are concurrently conducted in this manner to be made as the proper length.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to the production and filling of a sack from a tubular film web of thermoplastic material, preferably laterally creased and printed by format print. ， Regarding the method of sealing. Here, the tubular film web is provided at its leading end with a transverse joint, from which the open bag-forming part is cut, then filled and the open end of the bag is cut. The part is closed by a transverse joint.

[0002]

2. Description of the Related Art Such a method has been widely known in the past. For example, the portion which will later become a bag is pulled out from a tubular chain (chained in a chain) by a known method. The tubular chain is perforated at a predetermined distance so that the portion corresponding to the bag in the future can be torn along the perforation. And after closing the bottom joint,
The individual tubular parts are sent to a filling hopper which fills them with, for example, granular material, and when filled with a certain amount of material, the open bag is removed and the open end is pulled, Then it is sealed by special trimming means.

However, such a general method can also be implemented by a device according to DE-OS 37 15 685, for example. This device has a sliding and advancing roller, whereby the tip of each tubular film web provided with a transverse joint is pushed vertically and opens and closes in a horizontal plane. A bag, or a length of bag, hangs freely between the joint jaws. Below the joining jaws, a transverse cutting device is arranged, and below the transverse cutting device there is a gripper arranged in pairs on the conveying means, which is tubular. The suspended bag or bag cut from the film web of which the bottom joint is provided in the horizontal conveying direction is fed to the conveying means via a cooling line for cooling the transverse joint, which conveys the bag or Transport the bag to the filling station. The carrier means comprises a hub-shaped support member, which is rotatably mounted about a vertical axis, the support member having a radial arm, the free end of which is paired. There is a gripper arranged in. The cooling line is equipped with a cooling carrousel for cooling, which is a bag work piece provided with a transverse joint and separated from the tubular film web, and a bag work piece from a circular path joining station. To a means for transporting to the filling station. If the device comprises, for example, four radial arms, the joining means and the cutting means are provided above the first station. According to the prior art, each cycle of manufacturing a bag is a bag already provided with a transverse joint,
From the top, it leads to the first pair of open grippers, grabs it, and advances it by the length of a bag to separate it. Then a new transverse joint is formed at the end of the tubular film web and the carousel for cooling is rotated about 90 degrees intermittently until another bag with transverse joint is carried to the next station. Stay in this position. In a four-armed carousel for cooling, this operation is repeated until the first station rotates 270 degrees in three cycles. At this point the transverse joint is cooled and transported to the transport means for transporting the bag to the filling station, where the bag is filled and the open end of the bag open to seal the filled bag. After pulling up, the transverse joint is made.

At the filling station, the bag is filled with a predetermined amount of filling, generally a predetermined weight of filling. However, packings, such as granular packings, have different total volumes even with the same weight. This is because, for example, the water content of the object before filling is different. Different fill levels (heights) may result in inadequate open gaps between the bag and the fill after closing the bag at the transverse joint. This means that the bag will be poorly filled and therefore especially inconvenient when handling the bag.

When carrying out the general method by means of a device according to DE-OS 37 15 685, furthermore, the bag density is desired due to the density of the packing due to the inability to adjust the trimming means located inside the device. There is the problem of a tight fill or an unwanted excess of air between the filling and the sealing transverse joint.

The object of the present invention is therefore to develop a general method whereby it is ensured that all bags are firmly and sufficiently and completely filled, ie without unwanted waste volume. . In accordance with the invention, the general method is followed by varying the length of the tubular film web formed corresponding to the filling level of the bag to form a transverse joint that seals the bag and then the tubular film. Tubular film web, followed by a tubular notch, separating the bag-like part so that the web is intermittently advanced to the printed mark and does not simultaneously form a transverse joint that seals the next film-like part The object is achieved by the procedure of advancing again by a relatively short adjustable length, or by cutting off the advanced tubular film web again and forming a transverse joint which seals the tubular section. The invention is based on the knowledge that the volumetric properties of the packing do not change suddenly. When an operator detects that the volume of the packing has changed due to a change in volume density, the operator adjusts the sliding and advancing rollers of the device for advancing the tubular film web. Vary the length of the section of the and adapt this length to the filling level of each filling in the bag.

According to this method of the present invention, it is possible to effectively avoid the tubular film web being cut at the printed points by varying the length of each tubular film web section formed. The tubular film web is always advanced to the mark printed on the open side edge of the pouch, where it is cut and the bottom joint of the following section is matched to the length of the section being formed. ，
It is important that it can be changed by the operator according to the settings based on the filling level. Depending on the filling level of the filling, sections of the tubular film web may be formed in lengths of several centimeters, which are collected separately for reuse. Alternatively, this can be left in the bag as an extra length, especially when the width of the section of the tubular film web is very narrow.

According to another embodiment of the invention, the medium-weight tubular film web after severing the bag sections when the filling reaches a minimum volume density, ie a maximum volume level. Can be set to zero.
This is the case, for example, when filling a completely dry particulate material. In this case, the maximum possible length of the tubular film web section can be used when cutting off the tip bag section, so that the transverse joint of the next bag section can be formed simultaneously.

When, for example, as in EP-A 00 21 463, the corners are joined at the same time when the transverse joints are cut off and formed, the corners of the opening edge of the back of the tip and It has to be taken into account that the corners at the bottom joint of the bag pieces cannot be jointed simultaneously by one device. This is easily possible, for example, in tubular film webs with scattered prints. Therefore, in a more effective embodiment of the present invention, the corners at the opening edge of the bag section and the corners at the bottom seam are respectively joined by different corner joining devices. The section can be readjusted automatically or manually between both corner joining devices, corresponding to a medium length section. Join all corners
It has the advantage that it can be done with a transverse joint that seals subsequent tubular sections.

Alternatively, the joining of the corners at the opening edge of the bag section can be carried out together with the cutting of the cut, and the joining of the corners at the bottom seam can also be carried out together with the formation of the transverse joint. However, it must be accepted that in this variant of the method, the time taken for the procedure is longer than in the case where the corners at the opening edge of the bag section are joined and cut at the same time, and the speed is increased. It is not determined by the time required to cut the web, but by the time required to join the corners. If the medium advance is set to zero, both corner joining devices are advanced to the tubular film web at the same time.

[0011]

Embodiments of the present invention will now be described in detail with reference to the drawings. As shown in FIG. 2, the frame 1 comprises side walls 2 and 3. These side walls 2 and 3 are crossbars 4
Are connected to each other by. The crossbar 4 is provided with a fixed shaft 21 extending downward at substantially the center thereof, and an arm 5 of a swivel joint is attached to this shaft so as to be close to the crossbar 4. The arm 5 is a fluid piston cylinder. The unit 6 allows movement from one of the two end positions to the other. The cylinder of the fluid piston cylinder unit 6 is held stationary by a support member.

It can be seen in FIG. 5 that the free end of the arm 5 of the swivel joint, which serves as the angle lever, has a molded part 5 '. A holding roller 7 is provided in this bent portion. The function of this part will be discussed further in the description below. A vertical shaft 8 is further attached to the crossbar 4, and the vertical shaft 8 supports a four-arm rotary table 9 under the arm 5 of the swivel joint. The rotary table 9 can be intermittently rotated by 90 degrees by a belt 10 provided with teeth and a motor 11. The direction of rotation of the turntable is indicated by arrow A in FIG.

It can be seen from FIG. 2 that the protruding arm 9a of the rotary table 9 serves as a hub, so to speak. This is a molded part 12 provided with two pins 13 protruding upward.
Is equipped with. A lever 14 is rotatably attached around each pin 13, and the free end of the lever 14 is attached to the gripper 1.
It becomes 5. Each molded part is provided with two abutment surfaces 17, each of which is pressed by the force of a spring 16. The mutually facing levers 14 of the two adjacent arms 9a are operatively connected by a single connecting rod 18 so that the two associated grippers 15 can be opened and closed at the same time, whereby the bag 19 is gripped and held, for example. it can.

The gripper 15 is opened by a wedge-shaped or curved cam of the molded part 5'of the support arm 5. When the support arm 5 pivots by extending the piston rod of the piston-cylinder unit 6, the molding part 5 ′ is driven and the molding part 1 connected to the lever 14 is driven.
Apart from the two pressure rollers 20, the gripper 15 pivots around the pin 13 and moves away from the associated abutment surface 17. By the connecting rod 18, the grippers 15 of the adjacent molding parts are simultaneously released. In the position shown in FIG. 2, the gripper unit 15, which points to the upper edge of the figure and to the right edge of the figure, is released by the action of the fluid piston cylinder unit 6.

In order to prevent damage to the protruding molded part 5'even when the motor 11 is suddenly started, when the arm of the swivel joint pivots to open the gripper, the corner portion of the arm 5 of the swivel joint is rotated. The holding roller 7 attached to the moving member moves into the guide groove 22 of the locking plate 23. The locking plate 23
Are fixedly connected to the rotary table 9 by means of screw bolts 24, whereby by means of the holding rollers 7 of the swivel arm 5, that is, as long as the molding part 5 ′ is between the rollers 20 of the molding part 12, The rotation of the turntable is prevented.

From FIG. 1 it can be seen that the tube 26 moves from the roller 25 to the inlet station 27. The inlet station 27 is connected to the frame-shaped support 1 in a stationary state, the details of which are shown in FIG. FIG. 3 shows a part of the central shaft 8 and the rotary table 9 of the carousel for cooling. Between the gripper 15 and the contact surface 17 of the rotary table 9, a pipe section 19 with a bottom seam is fixed. However, it is still connected to the tubular web 26. On the grippers 15 and 17, a connecting rod 28 is provided parallel to the connecting rod. It carries a fixing strip 29 at its end facing the tubular web 26, which comprises a stationary support 30.
Co-act with the strip 31 on the opposite side fixed to the. In addition to this opposite strip 31, the support 30 has a knife receiving groove 32.
And a joint jaw 33. A knife 34 enters the knife receiving groove 32 to separate the bag 19 from the tubular web 26, at which time a second joining jaw 35 is provided to provide a transverse joint at the tip of the tubular web 26. Cooperate with.

Format printing (fo
rmat print) is printed. In this case, it is important to cut the tube so that it will not pass through when printing. Therefore, the progress of the tubular web is made intermittently by the printing marks provided on the opening edges of the respective bags. Changing the length of the bag segment is done by the corresponding operator cutting the segment long or short between the opening edge of the bag segment and the bottom joint of the next bag segment. The cut pieces of the tubular web that have been cut off are collected and reused. When separating and cutting at the opening edge, the joint jaw 33
Knife 34 is applied to tubular web 26 in the absence of any. As the tubular web advances by the section it cuts off, knife 34 is again applied to tubular web 26,
In this case, the joint jaw 33 is used. Thus, the cutting that separates the middle section and the subsequent formation of transverse joints of the bag sections are performed simultaneously.

Further above the joint jaws 33 and 35,
Clamping means are provided for clamping the tubular web 26. It comprises a rotary lever 39 provided with a fastening strip 38 and a fluid piston cylinder unit 40.
Can be moved by. An arm supporting the roller 41 is firmly connected to the rotating lever 39, and the roller 41 is arranged at a certain distance from the guide member 43 when the rotating lever 39 is in the tightening position. The guide member 43 is connected to a lever 44, and the lever 44 is engaged with a stop member 46 by a spring 45. The rotation axis of the lever 44 is set on the axis of the forward roller 47. The advancing roller 47 has a downwardly directed projection, which is the member 4 on the side opposite the clamping strip 38.
It becomes 8. To release the tightening after the bottom seam has been formed and the cut for separation made, the fluid piston cylinder units 37 and 40 are first actuated, so that the connecting rods 28, 36 and the lever 39 are separated. It is released by rotating. During this movement, the roller 41 is in contact with the cam surface of the guide member 43. By this,
Rotating the opposite member 48 in the direction of arrow C, the free depending one end of the tubular web 26 is released from the joining jaw 33 and the other side deflects to one. By diverting in this way, even if it is advanced by one bag by the advancing rollers 47 and 51 in the next cycle,
The tubular web does not collide with the support 30.

In addition, the tubular web 26 is
To prevent wrapping around 7 and 41, the advancing roller is provided with annular grooves 49, 50 into which the removable fingers 52, 53 engage. Of these fingers, 52 are held stationary and 53
On the opposite side as removable rakes 4
It is attached to 8.

[Brief description of drawings]

1 is a schematic side view of an apparatus for carrying out a method according to the invention for manufacturing a bag or a bag, which apparatus comprises a carousel for cooling.

FIG. 2 is a cross-sectional view showing the device taken along line II-II in FIG.

FIG. 3 is an enlarged view showing a portion surrounded by a dotted line in FIG.

FIG. 4 is an enlarged view showing a central portion of the device shown in FIG.

5 is a plan view of the locking plate according to FIG.

Claims (6)

[Claims] 1. A method for making, filling and sealing a bag from a tubular film web of thermoplastic material having lateral folds and printed by format printing, said tubular film comprising: At the leading edge of the film web, a transverse joint is provided, from which the tubular film web is cut away to form the open bag, then the bag is filled and the open end of the bag is pulled. In the method of closing by the transverse joint, the tubular film web is formed after the transverse joint for sealing the bag is already formed by changing the length of the formed section of the tubular film web according to the filling level of the bag. To the printed mark intermittently, and the sections that make up the bag are separated by the cutting means for separation without simultaneously forming a transverse joint that seals the next tubular section. A bag, characterized in that the following tubular film web is advanced again by a relatively short adjustment length, the advanced segment of the tubular film web is cut again, and a transverse joint is formed which seals the subsequent tubular segment. The method of manufacturing, filling and sealing this. 2. A moderate advance of the tubular film web after severing a sack section can be set to zero, and then when the sack section is severed, the transverse joining of the subsequent sack sections. The method according to claim 1, wherein the parts are formed simultaneously. 3. The joint of the corners of the bag section is added, wherein the corners of the opening edge of the bag section and the seam of the bottom are respectively joined by different corner joining devices, The method according to claim 1 or 2. 4. Method according to claim 3, characterized in that the distance between the separate corner joining devices can be readjusted automatically. 5. Joining all corners together with a transverse joint which seals the subsequent tubular section,
The method according to claim 3 or 4. 6. The joining of the corners at the opening edge of the bag section,
4. The method according to claim 3, wherein the cutting is performed together with the cutting, and the joint at the bottom seam is performed together with the transverse joint.
The method described.