JP2008080802A - Bag making machine and method for manufacturing bag - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem in which sealing faces of completed bags re-weld on a product receiving desk in a seal and cut system bag making machine, to make small the placement area of the bag making machine. <P>SOLUTION: A seal and cut unit device moves to and fro of an X position and a Y position by turns for every one sheet and carry out the sealing and cutting operation, thereby the sealing faces of the completion bags 4 are accumulated on a product receiving desk 11 so that the heat welding sealing parts 3a and 3b separate forward and backward, moreover, a seal and cut system and a rolled web direct delivery apparatus are combined, thereby the placement area of the length direction of the machine is reduced. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a bag making machine that intermittently transfers a film using a polyolefin-based resin as a raw material, welds it with a heat and pressure sealing means when the transfer is stopped, and cuts it with a cutting means.

  1 is a conventional bag making apparatus, but recently, there is a bag making apparatus using a seal and cut system shown in FIG. However, with this device, in the process of stacking the bags on the product cradle as a finished bag, one by one was stacked in the state of 3 in FIG. 3, and there was a problem that the sealing surfaces of the bags were re-welded. .

  Therefore, taking into account the temperature drop time of the seal part, the waiting time until the start of the next transfer process was increased immediately after the heat welding seal, and the film was transferred after the sealing surface was cooled to prevent re-welding. .

Problems to be solved by the invention

  FIG. 1 is a schematic view of a conventional bag making machine. In the process of stopping intermittent transfer by a transfer roll 5 driven by a servo motor 22, pressure sealing is performed by lowering the seal bar 6. (Adjustment is made so that the position of the seal 3 comes to the front of the cutter 7 by the cylindrical bar 9 for adjusting the seal position which is moved up and down by the handle 8). Therefore, in the conventional machine, the length of one bag is required by the transfer roll 5, and it is necessary to prevent the expansion of the heat seal surface in the molten state at the time of sealing. Between the seal bars 6, the film 2 was placed in a tension free state to reduce the tension in the traveling direction of the film and pooled at the position P. The space for one bag and the space for making the film hollow and maintaining a tension free state are required. Especially for long bags, the overall length of the machine is very long and the installation area becomes long. There is a problem that efficiency becomes worse.

  Further, in FIG. 1, a method in which the heat seal bar 6 descends while the film transfer is stopped and the film 2 is heat sealed while the original fabric 1 is fed in the arrow direction by the original fabric feed roll 10 and is intermittently transferred by the transfer roll 5 In FIG. 7, the heat sealing is performed in a state where the tension of the film is applied in the flow direction, so that the seal portion 3 becomes concave as shown in the side view B of the completed bag plan view A in FIG. was there.

  As a method for solving the above problem, a seal-and-cut method can be considered. FIG. 2 is a schematic view of a bag making machine according to this method. The heat-seal mechanism 6 and the film cutting blade 7 of FIG. 1 are combined, and a transfer roller 5 that rotates intermittently with a servo motor 22 as a driving source to transfer the film. Then, the raw fabric 1 is sent out by the drive motor 28 of the feed roll 27 that operates by sensing the position of the dancer roll 24. The finished bags 4 sealed and cut by the seal and cut unit 14 arranged in parallel with the transfer roll 5 are stacked on the product receiving base 11. In the process of stacking, as shown in FIG. 3, the heat-sealed portion 3 is overlapped at the same position, so that the semi-cooled sealed portion is re-welded with the sealed portion having residual heat in a bag made one bag ahead. There was a problem.

Means for solving the problem

  By using a seal-and-cut method combining a sealing device and a film cutting device and a film feeding device using film feeding speed control by tension roll position sensing shown in FIG. The total length of the machine was shortened by omitting the film pool portion at the P portion in FIG. 1 and omitting the empty space by merging the seal portion with the cut portion.

  In the conventional bag-making method of FIG. 1, with respect to the problem that the seal strength is lowered by the concave portion of the seal portion 3 in FIG. Solved by seal and cut method. That is, in the seal-and-cut method of FIGS. 2 and 3, during the heat-sealing seal by the downward pressure bonding of the seal bar 12, the heat tension is achieved by the fact that the tensile tension in the film flow direction becomes zero after the transfer roll 5. The seal portion 3 contracts as the seal portion is cooled, and the state of the seal 3 in FIG.

  A method for solving the problem that the sealing surfaces of the finished bag are re-welded on the product cradle in the seal-and-cut method will be described with reference to FIGS. A seal-and-cut unit 14 (inside the broken line) in which the seal bar 12, the cutter blade escape groove and presser bar 13, the seal cradle 15 and the cutter blade 16 are integrated is defined as T with the seal width Q plus α amount as T in the film transfer direction. 4 in the process of moving the X position / Y position of FIG. 4 back and forth along the film flow direction one by one along the film flow direction, and stacking the sealed and cut bags on the cradle 11. As 3a and 3b, the seal portions are stacked one after the other so that the seal portions do not overlap.

  The transfer amount of the film by the rotation of the transfer roll 5 is set by the controller 23 of the servo motor 22, and the required length amount of the bag is transferred. The controller is configured so that the predetermined length of the bag is L, the feed amount L of each sheet by the transfer roll 5 and the seal width plus α are T, and the feed amount of the pinch roll 5 is repeated L + T amount / LT amount. 23. The amount of T is a seal width plus α, which is a width that can prevent re-welding of the seals due to the seals overlapping on the product support 11.

  The seal-and-cut unit performs a seal-and-cut operation at the X position in FIG. 4 when the feed amount of the intermittent transfer is stopped at the LT amount, and the seal-and-cut unit operates at the Y position when stopped after the L + T amount feed. Cut operation.

The invention's effect

  The distance from the original film to the pinch roll 5 can be shortened by the film feed speed control device using the seal and cut method and tension roll position sensing, and the installation area of the machine is reduced.

  According to the present invention, since the finished bag is alternately arranged in the front-rear direction on the product cradle, the seal portion does not overlap on the product cradle, and re-welding of the seal portion can be prevented. As a result, it is not necessary to consider the seal cooling time, and the efficiency can be improved, and a bag having a high seal strength can be provided.

  An embodiment for shortening the overall length of the machine and solving the welding problem of the seal portion, which is a problem of the seal-and-cut method, will be described with reference to FIGS.

  With reference to FIG. One bag is transferred by the rotation of the film transfer roll 5, and a sealing and cutting operation is performed in the next stop process time zone. Following the film flow operation by the intermittent transfer rotation of the transfer roll 5, the film 2 is sent out. When the film transfer by the transfer roll 5 is started, the dancer roll 24 is at the lowest point, and the feeding motor 28 receiving the signal of S3 is in a stopped state. The film is pulled out by the rotation of the transfer roll 5, the dancer roll 24 is pulled up by the tension, and the position of the dancer roll moves in the direction of the position sensor S3 → S1. Each of the position sensors is set in the control panel 25 for S1 high speed, S2 medium speed, and S1 stop conditions, and controls the driving motor 28 for feeding. The web 1 is fed out and rotated by the rotation of the web receiving roll 27 connected to the motor 28. The original feed speed is synchronized with the intermittent film transfer speed by the transfer roll 5 by the feed motor rotation control based on the signals of the position sensors S1, S2, and S3.

  In the process of stopping the intermittent rotation of the pinch roll 5, the seal bar 12 and the cutter blade escape groove / film presser bar 13 are lowered by the crank mechanism 21 connected to the motor 20 to be heat-bonded by pressure, and at the same time, the seal bar 12. When the cutter blade escape groove and film presser bar 13 is in contact with the seal cradle 15, the flying cutter motor 17 rotates and the cutter blade 16 runs in a direction perpendicular to the film flow direction to cut the film. To do.

  FIG. 3 is an explanatory diagram of a seal and cut unit, in which a cutter blade flying device including a seal bar, a cutter blade escape groove and film presser bar 13 and a flying cutter motor 17 is unitized and set on a slide rail 18. The entire unit reciprocates on the slide rail by the cam 19.

  The seal and cut unit 14 (inside the broken line) moves back and forth along the film transfer direction on the slide rail 18 by an eccentric cam 19 using the motor 20 as a driving source. The reciprocating movement operation will be described with reference to FIG. In a mechanism that pushes and pulls the seal-and-cut unit 14 by a cam having a short-diameter circular arc portion 35 and a long-diameter circular arc portion 36 of the eccentric cam, and swings the seal-and-cut unit, the seal bar is rotated up and down by the same driving source. The cam 19 is rotated halfway during one rotation of the crank 21 for the cam, and in the process from the start of raising the seal bar after the completion of the lowering seal by the seal bar to immediately before the next lowering pressure bonding heat seal, The seal-and-cut unit reciprocates in the film traveling direction on the slide rail due to the difference in the lift of the arc portion. The seal and cut unit moves from the X position in FIG. 6 to the Y position during the process from the completion of the seal to the next descending seal, and moves from the Y position to the X position during the next same process.

  It is also possible to use an air cylinder or hydraulic cylinder as a drive source for unit movement instead of the above cam.

  The rotational speeds of the cam 19 and the crank 21 are determined by the setting of the diameters of the pulleys 31, 32, 33 and 34 in FIG. 6 such as a timing belt pulley which is a transmission means from the motor 20, and the power transmission pulley 34 to the crank mechanism is rotated once. In the meantime, the power transmission pulley 31 to the cam mechanism has a pulley diameter that makes a half rotation.

  The amount of film transported by the pinch roll 5 is L, the predetermined length of the bag, and T is the amount of movement of the seal-and-cut unit. The amount of feed per bag by the pinch roll 5 is alternated between the LT amount and the L + T amount. It is set by the controller 23 of the servo motor 22 to be repeated.

  The relationship between the film feed amount and the movement of the seal and cut unit is that when the film feed of the pinch roll 5 is the LT amount, the seal and cut unit stops at the position X in FIG. At the end of the L + T feed, the seal-and-cut unit is moved to the Y position by the cam mechanism 19 connected to the motor 20 to perform the sealing and cutting operation.

  Position detection sensors are provided at the X and Y positions in FIG. 4, and the respective position signals are transmitted to the controller of the film feed servo motor 23 to switch the feed amount of L + T / LT.

  The relationship between the film feed amount and the cut position will be described with reference to FIG. After the previous bag is cut at the position X in FIG. D, an L + T amount of film is fed in the direction of the arrow by the pinch roll 5 and cut at the Y position in the film feed stop process. Since the excess amount is cut from the X position to the Y position by the amount of T, the length of the bag is L + T− (T), and the bag is cut at a predetermined length L. Next, an LT amount of film is fed in the direction of the arrow, and cut at the X position in the film feeding stop process. Since the previous bag is cut at the Y position that is an extra long T amount, the cut position becomes longer by the T amount retracted from the Y position to the X position, and becomes L−T + (T), so it is cut at a predetermined length L. Is done. Thereafter, the sequence is repeated alternately with F, G, H, and I.

  Therefore, even if the film feed amount corresponding to the L + T amount and the L−T amount is alternately increased or decreased, the cutting position is moved accordingly, so that the length of each bag is constant, and the seal 3a · 3b is alternately stacked on the receiving table 11 by a distance of T.

  The amount of movement of the seal-and-cut unit can be produced normally with a seal width of around 5 mm. The normal seal width is in the range of 2 mm to 7 mm, and the amount of movement is 7 mm to 12 mm. Generally, the seal width is within 5 mm, and the movement amount is within 10 mm.

  One gist of the present invention is to prevent re-welding of the sealing surface, and for the purpose of avoiding the stacking of the sealing surface, it is sufficient if the relative distance between the bag making machine main body and the product receiving base is changed, and bag making as a changing means. A method is also conceivable in which the machine body or product cradle is moved back and forth for each bag, and the finished bags are moved back and forth on the cradle and stacked. In this method, the stability of the product on the cradle is poor and practical considerations such as moving speed are necessary.

  The embodiment of the present invention is not limited to the description unless it exceeds the gist.

  Schematic diagram of conventional bag making machine   Schematic of bag making machine according to the present invention   Side view of seal and cut unit   Seal and cut unit moving mechanism   Film feed amount and cut position correlation diagram   Correlation diagram of cam mechanism and crank mechanism   Illustration of seal shape

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Film raw material 2 Film 3 Heat welding seal part 3a Heat welding seal part 3b Heat welding seal part 4 Completion bag 5 Film transfer roll 6 Conventional machine seal bar 7 Conventional machine cutter blade 8 Handle for seal position adjustment 9 Seal position Adjustment bar 10 Conventional machine film feed roll 11 Product cradle 12 Seal bar with built-in seal and cut unit 13 Cutter escape groove presser bar 14 Seal and cut unit 15 Seal and cut unit support 16 Flying cutter blade 17 Flying Cutter drive motor 18 Slide rail for seal and cut unit swing 19 Seal and cut unit moving cam 20 Seal bar vertical motion / unit swing motor 21 Seal bar vertical motion crank mechanism 22 Pinch low Servo motor 23 for driving the pinch Servo motor controller 24 for driving the pinch rolls Dancer roll 25 for controlling the feeding motor Raw material feeding motor controller 27 Raw material feeding roll 28 Raw material roll driving motor 31 Cam shaft coupling pulley 32 Cam driving motor side Pulley 33 Crankshaft coupling pulley 34 Crank drive motor side pulley 35 Cam short-diameter arc portion 36 Cam long-diameter arc portion

S1 High speed position sensor S2 Medium speed position sensor S3 Stop position sensor

Claims (6)

  In a cylindrical polyolefin film bag making machine, a seal-and-cut unit that combines a sealing device and a film-cutting device is placed in a position parallel to the roll behind the film transfer roll, and the seal-and-cut unit advances the film. A bag making machine equipped with a mechanism that reciprocates along a direction.   In the mechanism in which an eccentric cam is used as a driving source of the reciprocating mechanism of claim 1 and the seal and cut unit is reciprocated, the cam rotates halfway while the seal bar up-and-down crank rotated by the same driving source makes one rotation. In the process from the completion of the lowering seal by the seal bar to the next lowering seal, the seal and cut unit moves along the film running direction on the slide rail due to the lift difference between the short circle arc portion and the long arc portion of the cam. A bag making machine equipped with a reciprocating mechanism.   The bag making machine according to claim 1, further comprising a step of intermittently transferring the film by a transfer pinch roll, wherein the transfer amount of the transfer roll is set to the L amount of the fixed size of the bag, and the seal width plus The α amount is set to T amount, and the setting of the servo motor for transfer is set so that the “LT amount feed / stop / L + T amount feed / stop” operation is repeated continuously, and the seal and cut unit is linked to the feed amount. A bag making machine characterized by alternately repeating a fixed position and a fixed position plus a T amount position.   It is a process of intermittently transferring the film by a transfer roll, and the feed amount of the pinch roll is the amount of L-T feed with the fixed amount of the bag as L amount and the seal width plus α amount as T amount. Set the servo motor so that stop, L + T feed, and stop are repeated continuously. When the film stops after LT feed, the seal and cut unit performs seal and cut at a fixed position, and then L + T feed. A bag manufacturing method using a bag making machine, comprising a seal and cut unit moving mechanism for performing seal and cut at a position where the seal and cut unit moves forward in the film flow direction when the film is stopped later. .   With the bag making machine body including the seal and cut unit that combines the sealing device and the film cutting device as the fixed position, the finished bag cradle moves back and forth in the film flow direction for each bag, and the finished bag rests on the cradle. A bag manufacturing method characterized by being alternately stacked at the front and rear positions.   The movement of a dancer roll that moves up and down due to the difference in relative stress between the weight of the dancer roll that holds the film at the film supply device and the tensile tension generated by intermittent transfer by the pinch roll in the bottom-seal bag making machine using the seal and cut method. Controls the film delivery means by the delivery motor by the position sensor signal to detect the film, and it is a mechanism to transport the film in a state where the film is always in tension, and the machine is installed by combining the seal-and-cut method and the delivery method. A bag making apparatus having a reduced area.

Images