JP2012136276A - Bag-making and packaging machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stably form a bottom of a flat bottom bag.SOLUTION: A bag-making and packaging machine 1 includes: a lateral seal mechanism 56; a first bending mechanism 57; and second bending mechanisms 58. Paired seal faces 30a, 30b of the lateral seal mechanism 56 pinch a tubular packaging material Fc in a lateral direction and heat-seal it to form a lower seal SLK2 of the bag B2. The first bending mechanism 57 bends the lower seal SLK2 in a direction crossing the lower seal SLK2. The second bending mechanisms 58 heat-seal ends SLE in a lateral direction, of the lower seal SL2 while bending the ends SLE to their vicinities. Both the seal faces 30a, 30b have first sites WA, WB and second sites FA1, FA2, FB1, FB2. Cross sections of the second sites FA1, FA2, FB1, FB2 have curved shapes more gentle than those of the first sites WA, WB. The second sites FA1, FA2, FB1, FB2 pinch at least part of at least one side of the ends SLE and the vicinities SLC.

Description

  The present invention relates to a bag making and packaging machine for producing flat bottom bags.

  2. Description of the Related Art Conventionally, a bag making and packaging machine has been used as a device for filling and packaging an article to be packaged such as confectionery in a bag while manufacturing the bag. In recent years, bag making and packaging machines for producing self-supporting bags are often used because of the ease of displaying products and the display effect. For example, in a bag making and packaging machine described in Patent Document 1 (Japanese Patent Laid-Open No. 2000-335511), a gusset-type bag is manufactured as a self-supporting bag. The bag making and packaging machine forms a lower seal portion of the bag by thermally sealing the cylindrical packaging material in the lateral direction while forming a gusset on the cylindrical packaging material. Thereafter, the bottom portion of the bag is formed by heat-sealing while folding the lower seal portion with respect to the main body portion of the bag using an L-shaped bending member.

  By the way, in the bag making and packaging machine described in Patent Document 2 (Japanese Patent Laid-Open No. 2000-177715), a low step portion is formed near the center in the lateral direction of the pair of seal surfaces of the lateral seal mechanism. This is because, near the center of the pair of sealing surfaces, there are many overlapping packaging materials to be sandwiched, and the packaging material is heat-sealed with uniform pressure even in the vicinity of such a center. However, the lower step portion and the other portions still have the same curved cross section.

  Now, in the case of manufacturing a flat bottom type bag as shown in FIG. 14 as a self-standing bag, the method of Patent Document 1 cannot form an appropriate bottom portion of the bag.

  A bag making and packaging machine according to Japanese Patent Application No. 2010-290766 (hereinafter referred to as Patent Document 3) by the present applicant includes a first folding mechanism and a second folding mechanism. The first folding mechanism bends the lower seal portion of the tubular packaging material in a direction crossing the lower seal portion to form a lower portion of the bag. The second bending mechanism performs heat sealing while bending the end portion of the lower seal portion with respect to the vicinity of the lower seal portion. In addition, the edge part of a lower seal part is an edge part of the horizontal direction of a lower seal part. The vicinity of the lower seal portion is a portion of the lower seal portion that is close to the end of the lower seal portion. Therefore, according to the bag making and packaging machine of Patent Document 3, a flat bottom type bag having an appropriate bottom portion can be manufactured.

  However, the weldability of the heat seal between the end portion of the lower seal portion and the vicinity portion by the second bending mechanism is not always sufficient. Such a problem is particularly true when the lower seal portion is formed in a corrugated shape. Therefore, the bottom part of the bag once formed may collapse.

  The subject of this invention is providing the bag making packaging machine which can form stably the bottom part of a flat bottom type bag.

  The bag making and packaging machine according to the first aspect of the present invention includes a lateral seal mechanism, a first folding mechanism, and a second folding mechanism, and manufactures a bag. The main bag includes a main body portion that surrounds the packaged object, and upper and lower seal portions and a lower seal portion above and below the main body portion. The horizontal sealing mechanism has a pair of sealing surfaces. The pair of sealing surfaces heat-seal while sandwiching the cylindrical packaging material in the lateral direction to form an upper seal portion and a lower seal portion. The first folding mechanism bends the lower seal portion of the tubular packaging material in a direction crossing the lower seal portion to form a lower portion of the bag. The lower part of the bag includes a lower seal part and a part of the main body part. The second bending mechanism performs heat sealing while bending the end portion of the lower seal portion with respect to the vicinity of the lower seal portion. The end part of the lower seal part is an end part in the lateral direction of the lower seal part. The vicinity of the lower seal portion is a portion of the lower seal portion that is close to the end of the lower seal portion. Each of the pair of sealing surfaces has a first portion and a second portion. The first portion has a first curved cross section. The second portion has a second curved shape that is gentler than the first curved shape. The second portion of the pair of sealing surfaces is heat-sealed while sandwiching at least a part of at least one of the end portion and the vicinity portion of the lower seal portion.

  Here, a first portion having a first curved cross section and a second portion having a second curved cross section that is gentler than the first curved cross section are formed on both seal surfaces of the lateral seal mechanism. A 2nd site | part is formed in the position which pinches | interposes at least one of the edge part of a lower seal part, and the vicinity part (part which faces when an edge part is bent) among both sealing surfaces. In other words, at least one of the end portion and the vicinity of the lower seal portion is a portion (both seals) having a gentler curved cross section than the other portions (portions that are sandwiched between the first portions of the seal surfaces and thermally sealed). A portion sandwiched by the second part of the surface and heat-sealed) is formed. Therefore, at the portion having such a gently curved cross section, the end portion of the lower seal portion and the vicinity thereof are firmly welded. Accordingly, the bottom portion of the flat bottom bag can be stably formed.

  The bag making and packaging machine according to the second aspect of the present invention is the bag making and packaging machine according to the first aspect, wherein the second part of the pair of seal surfaces is both the end part and the vicinity part of the lower seal part. And heat-sealing while sandwiching at least a part thereof. The second bending mechanism is configured to bend the end portion of the lower seal portion with respect to the vicinity portion, face at least a portion of the end portion sandwiched by the second portion and heat-sealed with at least a portion of the vicinity portion, and heat-seal both To do.

  Here, a 2nd site | part is formed in the position which pinches | interposes both the edge part of a lower seal part, and the vicinity part (part which faces when an edge part is bent) among both sealing surfaces. That is, a part (both seal surfaces) having a gentler curved cross section than the other part (a part that is sandwiched and heat-sealed by the first part of both seal surfaces) at both the end part and the vicinity of the lower seal part A portion which is sandwiched and heat-sealed by the second portion of the second portion. And, a portion having such a gently curved cross section in the end portion of the lower seal portion and a portion having such a gently curved cross section in the vicinity of the lower seal portion are mutually connected. Face to face and heat sealed. Therefore, the end portion of the lower seal portion and the vicinity portion are more firmly welded. Accordingly, the bottom of the flat bottom bag can be formed more stably.

  The bag making and packaging machine according to the third aspect of the present invention is the bag making and packaging machine according to the first aspect or the second aspect, and the second curved shape is a substantially flat shape.

  Here, the 2nd site | part of both sealing surfaces has a cross section of a substantially flat shape. That is, a portion having a substantially flat cross section (a portion sandwiched between the second portions of both seal surfaces and thermally sealed) is formed in at least one of the end portion and the vicinity portion of the lower seal portion. Therefore, in the portion having such a substantially flat cross section, the end portion and the vicinity portion of the lower seal portion are more firmly welded. Accordingly, the bottom of the flat bottom bag can be formed more stably.

  A bag making and packaging machine according to a fourth aspect of the present invention is the bag making and packaging machine according to any one of the first to third aspects, wherein the pair of sealing surfaces laterally cross the tubular packaging material. Heat sealing is performed while sandwiching in the direction, and the upper seal portion of the preceding bag and the lower seal portion of the succeeding bag are formed at the same time among the two bags manufactured continuously. The second part is not formed at a position where the upper seal portion of the preceding bag is sandwiched between the pair of seal surfaces, but is formed at a position where the lower seal portion of the subsequent bag is sandwiched.

  Here, a 2nd site | part is not formed in the position which pinches | interposes an upper seal part among both seal surfaces, but is formed in the position which pinches | interposes a lower seal part. That is, the lower seal portion is formed with a portion having a gently curved cross section (a portion sandwiched between the second portions of both seal surfaces and thermally sealed), but the upper seal portion has such a gentle shape. A portion having a curved cross section is not formed. Therefore, the upper seal portion is firmly heat-sealed. Therefore, it is possible to stably form the bottom portion of the flat bottom bag while maintaining the sealing performance of the upper seal portion.

  The bag making and packaging machine according to the fifth aspect of the present invention is the bag making and packaging machine according to any one of the first to fourth aspects, wherein the center part of the lower seal part of the pair of seal surfaces. Only the first part of the first part and the second part is formed at a position where the pin is sandwiched. The center portion of the lower seal portion is a portion of the lower seal portion that is closer to the center than the vicinity of the lower seal portion.

  Here, a 2nd site | part is not formed in the position which pinches | interposes the center part of a lower seal part among both sealing surfaces. That is, in the central portion of the lower seal portion, a portion having a gently curved cross section (portion sandwiched between the second portions of both seal surfaces and thermally sealed) is not formed. Therefore, the center part of the lower seal part is firmly heat-sealed. Therefore, it is possible to stably form the bottom portion of the flat bottom bag while maintaining the sealing performance of the lower seal portion.

  A bag making and packaging machine according to a sixth aspect of the present invention is the bag making and packaging machine according to any one of the first to fifth aspects, wherein the second folding mechanism includes the end of the lower seal portion. The end portion is heat-sealed by the residual heat at the time of heat sealing by the lateral seal mechanism while the end portion is bent.

  Here, the heat seal between the end portion of the lower seal portion and the vicinity thereof is performed by the residual heat of the heat seal of the lower seal portion. Here, the weldability between the end portion of the lower seal portion that is heat-sealed by residual heat and the vicinity thereof is maintained.

  According to the bag making and packaging machine according to the present invention, the bottom of the flat bottom bag can be stably formed.

1 is an external perspective view of a bag making and packaging machine according to an embodiment of the present invention. The schematic side view of a bag making packaging machine. The schematic perspective view of a bag making packaging machine. The figure which shows a guide mechanism, a 2nd bending mechanism, and a horizontal sealing mechanism. The side view of the guide mechanism of the closed state. The side view of the guide mechanism of the open state. Schematic of a horizontal seal mechanism. Schematic of a horizontal movement mechanism. The figure which shows a 1st seal jaw, a 2nd seal jaw, and a rotation mechanism. (A), (b) The figure which shows a motion of the 1st seal jaw. (A), (b) The figure which shows a motion of the 2nd seal jaw. The control block diagram of a bag making packaging machine. The rear view of a pillow-type bag. (A) The perspective view of a flat bottom type bag. (B) Bottom view of flat bottom bag. The bottom view of a bag lower part. The figure which shows the motion of a guide mechanism. The figure which shows the motion of a guide mechanism. The figure which shows the motion of a 1st bending mechanism. The figure which shows the motion of a 2nd bending mechanism. (A), (b), (c) The figure which shows the motion of a 2nd bending mechanism. (A) The bottom view of the bottom plate and bag lower part in a 1st advance position. (B) The bottom view of the bottom plate and bag in a 1st advance position. The figure which shows the guide mechanism at the time of formation of the bottom part of a bag, a side plate, and a bottom plate. The figure which shows a guide mechanism. (A) The front view of the 2nd seal jaw of a rear side. (B) XXIVB-XXIVB sectional drawing of (a). (C) XXIVC-XXIVC sectional drawing of (a). (A) The front view of the 2nd seal jaw of the front side. (B) XXVB-XXVB sectional drawing of (a). (C) XXVC-XXVC sectional drawing of (a). (A) The front view of the 2nd seal jaw of the rear side which concerns on a modification. (B) XXVIB-XXVIB sectional drawing of (a). (C) XXVIC-XXVIC sectional drawing of (a). (A) The front view of the 2nd seal jaw of the front side which concerns on a modification. (B) XXVIIB-XXVIIB sectional drawing of (a). (C) XXVIIC-XXVIIC sectional drawing of (a).

  Hereinafter, the bag making packaging machine 1 which concerns on one Embodiment of this invention is demonstrated, referring drawings. Note that “upper”, “lower”, “left”, “right”, “front”, and “rear” in the description of the bag making and packaging machine 1 are defined as shown in FIG.

(1) Whole structure The whole structure of the bag making packaging machine 1 is shown in FIG.1 and FIG.2. The bag making and packaging machine 1 is a machine that manufactures a product P in which an article C such as a snack is packed. The bag making and packaging machine 1 includes a bag making and packaging unit 5 that packs the articles C, a film supply unit 6 that supplies the film F that is the material of the bags B1 and B2 of the product P to the bag making and packaging unit 5, And a control unit 7 (see FIG. 12) for controlling the overall operation of the bag making and packaging machine 1. The article C to be packed in the bag making and packaging unit 5 is weighed by the combination weighing machine 2 disposed above the bag making and packaging unit 5. The bag making and packaging unit 5 packs the article C in line with the timing when the article C is supplied from the combination weighing machine 2.

  An operation panel 8 is disposed on the front surface of the bag making and packaging unit 5. The operation panel 8 includes a liquid crystal display and a touch panel that covers the liquid crystal display, and displays information indicating an operation state of the bag making and packaging machine 1 to an operator of the bag making and packaging machine 1, or bag making. The input of various commands to the packaging machine 1 is accepted.

  The bag making and packaging machine 1 forms a sheet-like film F supplied from the film supply unit 6 into a tubular film Fc by forming the sheet-like film F into a tubular shape by a forming mechanism 51 described later. Thereafter, bags B1 and B2 are manufactured by heat-sealing predetermined positions of the tubular film Fc in the vertical direction and the horizontal direction by a vertical sealing mechanism 53 and a horizontal sealing mechanism 56, which will be described later.

(2) Detailed structure (2-1) Film supply unit The film supply unit 6 is a unit which supplies the sheet-like film F with respect to the shaping | molding mechanism 51 which the bag making packaging unit 5 mentions later. The film supply unit 6 is disposed adjacent to the bag making and packaging unit 5. A film roll around which the film F is wound is set in the film supply unit 6. The film F is fed out from the film roll and supplied to the forming mechanism 51.

(2-2) Bag Making and Packaging Unit As shown in FIGS. 1 to 3, the bag making and packaging unit 5 includes a forming mechanism 51, pull-down belt mechanisms 52 and 52, a vertical seal mechanism 53, a guide mechanism 54, It has a horizontal sealing mechanism 56, a first folding mechanism 57, a second folding mechanism 58, and a support frame 12 that supports these mechanisms. The bags manufactured by the bag making and packaging unit 5 include a pillow type bag B1 as shown in FIG. 13 and a flat bottom type bag B2 as shown in FIG.

  As shown in FIG. 13, the pillow-type bag B1 includes a bag body portion FL1 that surrounds the article C, an upper seal portion SL1 that closes the upper side of the bag body portion FL1, and a lower seal portion that closes the lower side of the bag body portion FL1. SL2. A vertical seal portion LSP extending in the vertical direction is formed on the back surface of the bag B1.

  As shown in FIG. 14, the flat bottom bag B2 is a self-supporting bag having a bottom portion FB. The bag B2 includes a bag body portion FL2 that surrounds the article C, an upper seal portion SL1 that closes the upper side of the bag body portion FL2, and a lower seal portion SL2 that closes the lower side of the bag body portion FL2. A vertical seal portion LSP extending in the vertical direction is formed on the back surface of the bag B2. The bag body portion FL2 has a first surface S1 having a vertical seal portion LSP, a second surface S2 facing the first surface S1, and side surfaces S3 and S3 sandwiched between the first surface S1 and the second surface S2. . In the present embodiment, no crease is formed at the boundary between the first surface S1 and the second surface S2, and the side surfaces S3 and S3, and the vicinity of the boundary is smoothly curved. In other words, no gusset is formed in the bag B2. The bottom portion FB mainly includes a lower seal portion SL2 and lower portions of the first surface S1, the second surface S2, and the side surfaces S3 and S3.

(2-2-1) Forming mechanism The forming mechanism 51 forms the sheet-like film F sent from the film supply unit 6 into a cylindrical shape. As shown in FIGS. 2 and 3, the forming mechanism 51 includes a tube 11a and a former 11b.

(2-2-1-1) Tube The tube 11a is a cylindrical member extending in the vertical direction, and has openings at the upper and lower ends. The tube 11a is disposed at the central opening of the top plate 29 of the support frame 12, and is integrated with the former 11b via a bracket (not shown). The opening at the upper end of the tube 11a has a funnel shape. As shown in FIG. 3, the article C falling from the combination weighing machine 2 (see FIG. 1) by a predetermined amount is thrown through the funnel-shaped opening and falls through the inside of the tube 11a. The combination weighing machine 2 includes a feeder, a pool hopper, a lightweight hopper, and a collective discharge chute.

(2-2-1-2) Former The former 11b is arranged so as to surround the tube 11a. The shape of the former 11b is such that the film F is wound around the outer surface of the tube 11a while passing through the gap between the former 11b and the tube 11a, and is formed from a sheet shape to a cylindrical shape. The former 11b is also fixed to the support frame 12 via a support member (not shown).

(2-2-2) Pull-down belt mechanism The pull-down belt mechanisms 52 and 52 are supported by a support member (not shown) suspended from the top plate 29 of the support frame 12. As shown in FIG. 3, the pull-down belt mechanisms 52 and 52 are arranged symmetrically with respect to the tube 11a. The pull-down belt mechanisms 52 and 52 extend in the vertical direction along the tube 11a and convey the tube film Fc wound around the tube 11a while adsorbing the tubular film Fc. The pull-down belt mechanisms 52 and 52 include driving rollers 21 and 21, driven rollers 22 and 22, and belts 23 and 23 having a suction function, respectively.

(2-2-3) Vertical Seal Mechanism The vertical seal mechanism 53 is supported by a support member (not shown) that is suspended from the top plate 29 of the support frame 12, and extends vertically along the tube 11a. It extends.

  As shown in FIG. 3, the vertical sealing mechanism 53 heats the overlapping portion of the tubular film Fc wound around the tube 11 a while pressing the tube 11 a against the tube 11 a with a constant applied pressure in the vertical direction. The vertical seal mechanism 53 includes a heater and a heater belt that is heated by the heater and contacts an overlapping portion of the tubular film Fc.

(2-2-4) Guide Mechanism As shown in FIG. 3, the guide mechanism 54 is disposed between the tube 11 a and the lateral seal mechanism 56. The guide mechanism 54 spreads the tubular film Fc in the depth direction (front-rear direction) from the inside after the lower seal portion SL2 is formed on the tubular film Fc by the lateral seal mechanism 56 when the bag B2 is manufactured.

  As shown in FIGS. 4, 5, and 23, the guide mechanism 54 includes guide members 41 and 41, rotation mechanisms 42 and 42, pressing portions 43 and 43, transmission mechanisms 44 and 44, and a pressing mechanism 45. , 45, L-shaped members 46, 46, and spreaders 47, 47.

(2-2-4-1) Guide member The guide members 41 and 41 are attached to the front and rear of the lower end portion of the tube 11a. Each of the guide members 41 and 41 has an inverted U-shape. In other words, each of the guide members 41 and 41 seems to have a substantially rectangular plate-like member that is appropriately bent and cut out from the center to the lower side. Have a different shape. That is, the guide members 41, 41 have four leg tip portions 41a,... (See FIGS. 17 and 18). As will be described later, the guide members 41 and 41 come into contact with the tubular film Fc from the inside, but the contact area with the tubular film Fc is reduced by this notch. As a result, the frictional resistance between the guide members 41 and 41 and the tubular film Fc is reduced, and the durability of the tubular film Fc is improved. Further, the article C that has fallen inside the tube 11 a is less likely to be clogged in the guide mechanism 54 due to this notch. Furthermore, the guide members 41 and 41 are reduced in weight by this notch, and the force required to open and close the guide members 41 and 41 described later is reduced.

  The cylindrical film Fc that has been transported to the guide members 41 and 41 while wrapping the tube 11a is transported further downward along the guide members 41 and 41 while wrapping the guide members 41 and 41.

(2-2-4-2) Rotation Mechanism As shown in FIGS. 5 and 6, the rotation mechanisms 42 and 42 are attached near the upper ends of the guide members 41 and 41, respectively. 41 is a rotation axis. The rotation mechanisms 42 and 42 rotate the guide members 41 and 41 symmetrically with respect to the center line of the tube 11a. As a result, the leg tip portions 41a,... Facing each other in the front-rear direction move in directions opposite to each other and approach and separate. In the state where the leg tip portions 41a,... Facing each other in the front-rear direction are separated from each other (the guide members 41, 41 are opened), the tubular film Fc enclosing the guide members 41, 41 is It is pushed and expanded in the depth direction (front-rear direction) from the inside by the portions 41a,.

(2-2-4-3) Pressing part The pressing parts 43 and 43 are attached to the vicinity of the left end and the right end of the guide members 41 and 41, respectively. The pressing portions 43 and 43 operate transmission mechanisms 44 and 44 described later by being pressed by pressing mechanisms 45 and 45 described later, respectively. The pressing parts 43, 43 are made of stainless steel.

(2-2-4-4) Transmission mechanism The transmission mechanisms 44 and 44 transmit the pressing force acting on the pressing portions 43 and 43 to the rotating mechanisms 42 and 42, respectively, and guide the guide members 41 and 41 to the center of the tube 11a. Rotate symmetrically around the line.

(2-2-4-5) Pressing mechanism The pressing mechanisms 45 and 45 are mechanisms that press the pressing portions 43 and 43, respectively. The pressing mechanism 45 is constituted by, for example, an air cylinder which is a kind of reciprocating actuator, and is controlled by a speed controller (not shown). In a state where the pressing mechanisms 45, 45 are not pressing the pressing portions 43, 43, as shown in FIG. 5, the guide members 41, 41 extend substantially vertically due to their own weight (the guide members 41, 41 are closed). State). On the other hand, when the pressing mechanisms 45 and 45 are pressing the pressing portions 43 and 43, the guide members 41 and 41 are opened as shown in FIG. The depth dimension (the dimension in the front-rear direction) of the bag B2 can be adjusted by the opening amount L of the guide members 41, 41. The pressing mechanisms 45 and 45 are made of rubber or resin, and noise due to contact with the pressing portions 43 and 43 is reduced.

(2-2-4-6) L-shaped member L-shaped members 46 and 46 are arranged inside guide members 41 and 41 as shown in FIG. The L-shaped members 46 and 46 include shaft portions 46a and 46a, and pedestals 46b and 46b that are continuous with the lower ends of the shaft portions 46a and 46a, respectively. The shaft portions 46a and 46a extend in the vertical direction in the vicinity of the left and right portions of the guide members 41 and 41, respectively. The cradle 46b, 46b extends in the left-right direction. The lower end surfaces of the pedestals 46b and 46b receive pressure applied from the side plates 81 and 81 at the second forward position, which will be described later, respectively, and the film F (specifically, end portions EP, EP and The adjacent portions CP1, CP1) are sandwiched between the side plates 81, 81.

(2-2-4-7) Spreader The spreaders 47 and 47 are attached to the vicinity of the left end and the right end of the guide members 41 and 41, respectively. The spreaders 47, 47 are elastic stainless plate members. As shown in FIG. 23, the basic shape of the spreaders 47, 47 (the shape in a state where no external force is applied) is a shape that extends generally in the vertical direction and opens to the left and right in the downward direction. The lower ends of the spreaders 47, 47 reach the vicinity of the lower end surfaces of the leg tip portions 41a,... And the pedestals 46b, 46b in the vertical direction. The spreaders 47 and 47 push the tubular film Fc (particularly, the portion in contact with the vicinity of the lower end portion of the spreaders 47 and 47) conveyed in such a manner as to wrap around the spreaders 47 and 47 from the inside to the outside. As a result, the tubular film Fc (particularly, in the vicinity of the portions that become the upper seal portion SL1 and the lower seal portion SL2 of the bag B2) is formed into a flat shape.

(2-2-5) Horizontal Seal Mechanism As shown in FIG. 3, the horizontal seal mechanism 56 is disposed below and supports the forming mechanism 51, the pull-down belt mechanisms 52 and 52, the vertical seal mechanism 53, and the guide mechanism 54. It is supported by the frame 12. As shown in FIGS. 7 to 9, the horizontal seal mechanism 56 horizontally moves the main body portions 63a and 63b, the rotation mechanisms 65a and 65b having a function of rotating the main body portions 63a and 63b, and the main body portions 63a and 63b. A horizontal movement mechanism 60 having a function of causing the first sealing jaws 61a and 61a and the second sealing jaw 62a attached to the rear body portion 63a, and the first sealing jaw 61b attached to the front body portion 63b. 61b and a second sealing jaw 62b. The first seal jaws 61a and 61a are paired with the first seal jaws 61b and 61b, respectively. The second seal jaw 62a is paired with the second seal jaw 62b. That is, the horizontal seal mechanism 56 has two pairs of first seal jaws 61a, 61b,... And a pair of second seal jaws 62a, 62b. The tubular film Fc is conveyed downward in a state where the broken line C0 shown in FIG. 7 is the center in the width direction of the tubular film Fc.

(2-2-5-1) Main Body As shown in FIGS. 7 and 9, the main bodies 63a and 63b have a shape similar to an ellipse in a side view. Specifically, the main body portions 63a and 63b are respectively provided with first end portions ED1 and ED1 whose distance from the center is the first length L1, and second end portion ED2 whose distance from the center is the second length L2. And have. The second length L2 is shorter than the first length L1. The main body portions 63a and 63b are arranged on both sides with the tubular film Fc interposed therebetween. In FIG. 7, the main body portions 63a and 63b are arranged with a broken line C0 interposed therebetween.

  The body portions 63a and 63b support first seal jaws 61a, 61b,... And second seal jaws 62a and 62b, which will be described later (see FIGS. 7 and 9). Specifically, first seal jaws 61a, 61b,... Are supported by the first end portions ED1, ED1,..., Respectively, and second seal jaws 62a are respectively supported by the second end portions ED2, ED2. 62b are supported. The first seal jaws 61a, 61b,... And the second seal jaws 62a, 62b are all detachable from the main body portions 63a, 63b.

  The main body parts 63a and 63b can be rotated symmetrically with respect to the broken line C0 as a reference by driving rotation mechanisms 65a and 65b described later. Specifically, in FIGS. 7 and 9, the main body 63a rotates clockwise, and the main body 63b rotates counterclockwise. The main body parts 63a and 63b can be moved horizontally by a horizontal movement mechanism 60 described later. Specifically, the main body portions 63a and 63b can be moved toward and away from each other symmetrically with respect to the broken line C0 in FIG.

(2-2-5-2) Rotation Mechanism The rotation mechanisms 65a and 65b have center axes C1 and C2 provided at the centers of the main body portions 63a and 63b, respectively, and are driven by a drive motor (not shown). The central axes C1 and C2 extend in a direction perpendicular to the paper surface of FIG. When the central axes C1 and C2 are rotated by the drive motor, the main body portions 63a and 63b also rotate. The rotation mechanisms 65a and 65b rotate the main body parts 63a and 63b in directions opposite to each other.

(2-2-5-3) Horizontal Movement Mechanism The horizontal movement mechanism 60 is a mechanism that allows the main body portions 63a and 63b to move horizontally. Specifically, the horizontal movement mechanism 60 is a mechanism that causes the main body portions 63a and 63b to approach and separate from each other symmetrically in the longitudinal direction with respect to the broken line C0 in FIG. As shown in FIG. 8, the horizontal movement mechanism 60 includes horizontal movement plates 64a and 64b, a horizontal movement plate drive mechanism 55, and a drive motor (not shown).

(2-2-5-3-1) Horizontal moving plates The horizontal moving plates 64a and 64b are attached to both ends of the main body portions 63a and 63b in the left-right direction (perpendicular to the plane of FIG. 7 and FIG. 9). Specifically, they are attached to both ends of the central axes C1 and C2, respectively. The horizontal movement plates 64a and 64b are horizontally moved by a horizontal movement plate driving mechanism 55 described later.

(2-2-5-3-2) Horizontal movement plate drive mechanism The horizontal movement plate drive mechanism 55 includes a drive mechanism 75 for moving the horizontal movement plates 64a and 64b close to and away from each other, and the horizontal movement plates 64a and 64b. It has a guide part and a guide rail (not shown) that are slidably supported in the horizontal direction.

  The drive mechanism 75 includes a ball screw 17i, first and second nut members 17a and 17b, first and second connecting rods 17c and 17d, a pair of third connecting rods 17e, a fourth connecting rod 17f, It has joints 17g and 17h. The ball screw 17i is rotated by a servo motor 80 (see FIG. 7). The first and second nut members 17a and 17b are screwed into the ball screw 17i. The first and second connecting rods 17c and 17d are provided so as to be orthogonal to the ball screw 17i in a horizontal plane. The pair of third connecting rods 17e is provided along the moving direction of the horizontal moving plates 64a and 64b. The fourth connecting rod 17f is provided in parallel with the third connecting rod 17e. The first connecting rod 17c is connected to a pair of third connecting rods 17e via a joint 17g. The distal ends of the pair of third connecting rods 17e are fixed to the side end surfaces of the horizontal moving plate 64b. The pair of third connecting rods 17e penetrates the horizontal movement plate 64a in a slidable manner. The second connecting rod 17d is connected to the fourth connecting rod 17f via a joint 17h. The tip of the fourth connecting rod 17f is fixed to the side end surface of the horizontal moving plate 64a. The portion where the first nut member 17a is screwed with the ball screw 17i and the portion where the second nut member 17b is screwed with the ball screw 17i are reverse screws. The servo motor 80 causes the horizontal moving plates 64a and 64b to approach and separate from each other by rotating the ball screw 17i.

(2-2-5-4) First Seal Jaw The first seal jaws 61a, 61b,... Are used when continuously manufacturing the pillow type bag B1. The first seal jaws 61a, 61b,... Each have a seal surface. The seal surfaces of the first seal jaws 61a, 61b,... Extend slightly longer than the dimensions of the tubular film Fc in the left-right direction (that is, the direction perpendicular to the paper surface of FIGS. 7 and 9). In the first seal jaws 61a, 61b,..., Heaters for heating the respective seal surfaces are incorporated. The heated sealing surfaces of the paired first sealing jaws 61a, 61b,... Heat-seal the sandwiched portions while sandwiching the tubular film Fc in the lateral direction. Thereby, among two bags B1 manufactured continuously, the upper seal portion SL1 of the preceding bag B1 and the lower seal portion SL2 of the subsequent bag B1 are formed simultaneously.

  As shown in FIGS. 10A and 10B, the first sealing jaws 61a, 61b,... Heat the tubular film Fc in the lateral direction while turning around the central axes C1, C2. Seal. Specifically, the first seal jaws 61a, 61b,... Each draw a D-shaped trajectory by a combination of horizontal reciprocation by the horizontal movement mechanism 60 and rotational movement by the rotation mechanisms 65a, 65b. The first seal jaws 61a, 61b,... Are paired with the first seal jaws 61a, 61b,... That form a pair while drawing a substantially straight I-shaped trajectory of the D-shaped trajectory. A cylindrical film Fc is sandwiched between and heat sealed.

(2-2-5-5) Second Seal Jaw The second seal jaws 62a and 62b are used when the flat bottom bag B2 is manufactured intermittently. The second seal jaws 62a and 62b have seal surfaces 30a and 30b, respectively. The seal surfaces 30a and 30b extend slightly longer than the dimensions of the tubular film Fc in the left-right direction (that is, the direction perpendicular to the paper surface of FIGS. 7 and 9). The second seal jaws 62a and 62b incorporate heaters for heating the seal surfaces 30a and 30b, respectively. The heated sealing surfaces 30a and 30b heat-seal the sandwiched portion while sandwiching the tubular film Fc in the lateral direction. Thereby, among two bags B2 manufactured continuously, the upper seal portion SL1 of the preceding bag B2 and the lower seal portion SL2 of the subsequent bag B2 are formed simultaneously.

  As shown in FIGS. 11A and 11B, the second seal jaws 62a and 62b reciprocate horizontally in the horizontal direction by the horizontal movement mechanism 60, thereby approaching and separating from the tubular film Fc. The second seal jaws 62a and 62b are heat-sealed by sandwiching the tubular film Fc between the pair of front and rear seal surfaces 30a and 30b at positions closest to each other.

  As shown in FIG. 24A, the rear seal surface 30a has a corrugated part WA and four flat parts FA1, FA1, FA2, FA2 surrounded by the corrugated part WA. As shown in FIG. 24B, the corrugated portion WA has a corrugated shape in a cross-sectional view of the seal surface 30a in the short direction. As shown in FIG. 24C, the flat portions FA1, FA2,... Have a flat shape in a cross-sectional view of the seal surface 30a in the short direction. The shape of the cross section in the short direction of the seal surface 30a of the portion of the corrugated portion WA that is not aligned with the flat portions FA1, FA2,... In the short direction of the seal surface 30a is the upper side (the seal surfaces 30a, 30 are It is a shape in which a mountain and a valley appear eight times in the order of a mountain and a valley from the upper side when they are closest to each other. In addition, in the sealing surface 30a shown to Fig.24 (a), a continuous line has shown the peak and the broken line has shown the trough.

  Similarly, as shown in FIG. 25A, the front seal surface 30b has a corrugated part WB and four flat parts FB1, FB1, FB2, and FB2 surrounded by the corrugated part WB. As shown in FIG. 25B, the corrugated part WB has a corrugated shape in a cross-sectional view of the seal surface 30b in the short direction. As shown in FIG. 25 (c), the flat portions FB1, FB2,... Have a flat shape in a cross-sectional view in the short direction of the seal surface 30b. The shape of the cross section in the short direction of the seal surface 30b of the portion of the corrugated portion WB that is not aligned with the flat portions FB1, FB2,... In the short direction of the seal surface 30b is the upper side (the seal surfaces 30a and 30b are It is a shape in which the peaks and valleys appear eight times in the order of valleys and peaks from the upper side when they are closest to each other. In addition, in the sealing surface 30b shown to Fig.25 (a), a continuous line has shown the peak and the broken line has shown the trough.

  The seal surfaces 30a and 30b mesh with each other at positions closest to each other. Specifically, at the position where the seal surfaces 30a and 30b are closest to each other, the corrugated portion WA of the seal surface 30a faces the corrugated portion WB of the seal surface 30b and contacts with the tubular film Fc interposed therebetween. At the same time, the flat portions FA1 and FA1 of the seal surface 30a face the flat portions FB1 and FB1 of the seal surface 30b, respectively, and come into contact with the cylindrical film Fc. At the same time, the flat portions FA2 and FA2 of the seal surface 30a face the flat portions FB2 and FB2 of the seal surface 30b, respectively, and come into contact with the cylindrical film Fc. That is, at the position where the seal surfaces 30a and 30b are closest to each other, the eight crests of the seal surface 30a mesh with the eight troughs of the seal surface 30b, and the eight troughs of the seal surface 30a are each eight of the seal surface 30b. Mesh with two mountains.

  As shown in FIGS. 24 (a), 25 (a), and 15, the two flat portions FA1 and FA1 seal the two seal end portions SLE and SLE of the lower seal portion SL2 on the seal surface 30a, respectively. It is formed at a position sandwiched between two flat portions FB1, FB1 of the surface 30b. Note that the seal end portions SLE and SLE are both end portions in the horizontal direction of the lower seal portion SL2. The two flat portions FA2 and FA2 are formed at positions where the two seal neighboring portions SLN and SLN of the lower seal portion SL2 are sandwiched between the two flat portions FB2 and FB2 of the seal surface 30b on the seal surface 30a. The The seal vicinity portions SLN and SLN are portions of the lower seal portion SL2 that are close to the seal end portions SLE and SLE. The seal vicinity portions SLN and SLN are portions facing the seal end portions SLE and SLE when the seal end portions SLE and SLE are bent by the second bending mechanism 58 in a manner described later.

  Similarly, as shown in FIG. 24 (a), FIG. 25 (a), and FIG. 15, the two flat portions FB1, FB1 have two seal end portions SLE, SLE of the lower seal portion SL2, respectively, of the seal surface 30b. Is formed between the two flat portions FA1 and FA1 of the seal surface 30a. The two flat portions FB2 and FB2 are formed in the seal surface 30b at positions where the two seal vicinity portions SLN and SLN of the lower seal portion SL2 are sandwiched between the two flat portions FA2 and FA2 of the seal surface 30a. The

  Further, as shown in FIG. 24A, the flat portions FA1, FA2,... Are located on the upper side of the seal surface 30a in the short direction (the positions where the seal surfaces 30a and 30b are closest to each other). The upper half when it is on. On the other hand, the lower half of the seal surface 30a in the short direction of the seal surface 30a (the lower side when the seal surfaces 30a and 30b are closest to each other) consists of only the corrugated portion WA.

  Similarly, as shown in FIG. 25 (a), the flat portions FB1, FB2,..., Of the seal surfaces 30b, the upper side in the short direction of the seal surface 30b (the seal surfaces 30a and 30b are closest to each other). Formed in half). On the other hand, the lower half of the seal surface 30b in the short direction of the seal surface 30b (the lower side when the seal surfaces 30a and 30b are closest to each other) consists only of the corrugated portion WB.

  In other words, the flat portions FA1, FA2, FB1, FB2,... Are not formed at positions where the upper seal portion SL1 of the preceding bag B2 is sandwiched among the seal surfaces 30a, 30b, but below the subsequent bag B2. It is formed only at a position where the seal portion SL2 is sandwiched. As a result, the upper seal portion SL1 is not formed with a portion having a flat cross section in the short direction, that is, a flat surface is not formed. In other words, the upper seal portion SL1 has a shape that undulates in the short direction over the entire region, so that the sealing performance is maintained. On the other hand, as shown in FIG. 15, the lower seal portion SL2 has four flat portions FPE, FPE, FPN, FPN (flat portions FA1, F1 of the seal surface 30a) having a flat cross section in the short direction of the lower seal portion SL2. Are formed between FA2,... And flat portions FB1, FB2,.

(2-2-6) First folding mechanism The first folding mechanism 57 is used when manufacturing the flat bottom bag B2.

  The first bending mechanism 57 has a bottom plate 50 shown in FIGS. 3, 5, 6 and 18 and an air cylinder which is a kind of reciprocating actuator not shown. The bottom plate 50 is disposed above the lateral seal mechanism 56. The reciprocating actuator is controlled by a speed controller (not shown). The bottom plate 50 is reciprocated in the horizontal direction between the first retracted position (position in FIG. 5) and the first forward position (position in FIG. 6) by driving the reciprocating actuator. Proximity and separation. The bottom plate 50 in the first retracted position maintains a certain distance from the tubular film Fc, and the bottom plate 50 in the first forward position contacts the lower part of the tubular film Fc.

  The bottom plate 50 is a metal plate-like member having a resin applied on the surface, and has a shape like a fork having blades at the left and right ends, as shown in FIG. Specifically, the bottom plate 50 includes a base portion 50a, a left blade portion 50b corresponding to the leftmost blade, and a right blade portion 50c corresponding to the rightmost blade. The blade portions 50b and 50c extend forward from the base portion 50a toward the tubular film Fc.

  After the bottom seal portion SL2 is formed on the tubular film Fc, the bottom plate 50 moves to the first forward position below the tubular film Fc, and the bottom seal portion SL2 extends in the direction in which the lower seal portion SL2 extends (left-right direction). ) And push it down in the direction intersecting (front-back direction). Accordingly, the lower seal portion SL2 is bent with respect to the lower portion of the bag main body portion FL2, and a bag lower portion FA (see FIG. 15) is formed on the tubular film Fc. The bag lower portion FA has a lower seal portion SL2 of the bag B2 and lower portions of the first surface S1, the second surface S2, and the side surfaces S3 and S3. The bag lower portion FA is in a state before the bottom portion FB shown in FIG. 14B is formed.

(2-2-7) Second folding mechanism The second folding mechanisms 58, 58 are used when the flat bottom bag B2 is manufactured.

  The second bending mechanisms 58, 58 are disposed above the lateral seal mechanism 56, as shown in FIGS. The second bending mechanisms 58 and 58 include side plates 81 and 81, support members 82 and 82, rotation shafts 84 and 84, first drive units 83 and 83, and a second drive unit (not shown). (See FIG. 4). The side plates 81 and 81 are metal plate-like members having a resin applied on the surface, and each has a predetermined length in the depth direction (front-rear direction) of the tubular film Fc. The side plates 81 and 81 are formed with recesses 81b and 81b that are recessed from the contact surfaces 81a and 81a with the tubular film Fc, respectively (see FIG. 22).

  Hereinafter, although the operation of the right second bending mechanism 58 will be described, the left second bending mechanism 58 performs a symmetrical operation with the right second bending mechanism 58 with respect to the center line of the tube 11a. .

  The side plate 81 has a second retracted position (position shown in FIG. 20A) and a second advanced position (position extending in the horizontal direction shown in FIG. 20C) by the first driving section 83 and a second driving section (not shown). Reciprocates between. The side plate 81 moves to the second forward position in a state where the bottom plate 50 is at the first forward position, and pushes down the side part EP of the bag lower part FA in the direction (left-right direction) in which the lower seal part SL2 extends. Accordingly, the side portion EP of the bag lower FA is heat-sealed while being bent with respect to the vicinity CP1 of the bag lower FA. The side portions EP and EP of the bag lower FA are both sides of the bag lower FA in the direction (left-right direction) in which the lower seal portion SL2 extends. Note that the vicinity portions CP1 and CP1 of the bag lower FA, which will be described later, are portions of the bag lower FA close to the side portions EP and EP.

  The side plate 81 is connected to the support member 82 via the rotation shaft 84. The side plate 81 is rotated around the rotation shaft 84 by a second drive unit (not shown). The support member 82 is connected to the first drive unit 83. The first drive unit 83 is configured by an air cylinder or the like which is a kind of reciprocating actuator, and is controlled by a speed controller (not shown). The support member 82 reciprocates in an oblique direction by the drive of the first drive unit 83, and approaches and separates from the side part EP of the bag lower FA. As the support member 82 moves, the side plate 81 moves from the second retracted position (the position shown in FIG. 20A) to the second intermediate position (the position extending obliquely in FIG. 20C). It rotates around the rotation shaft 84 and moves from the second intermediate position to the second forward position (a position extending in the horizontal direction in FIG. 20C). Thereby, the side plate 81 contacts the side part EP of the bag lower part FA, and pushes down the side part EP so that the side part EP contacts the vicinity part CP1.

(2-3) Control Unit The control unit 7 includes a CPU, a ROM, a RAM, a flash memory, and the like, and controls the operation of each unit of the bag making and packaging machine 1 by reading and executing a program in the flash memory. As shown in FIG. 12, the control unit 7 includes a film supply unit 6, a pull-down belt mechanism 52, a vertical sealing mechanism 53, a guide mechanism 54, a horizontal sealing mechanism 56, a first folding mechanism 57, a second folding mechanism 58, and an operation panel. 8 is connected.

(3) Operation of the bag making and packaging machine (3-1) Manufacturing operation of the pillow type bag The operation of the bag making and packaging machine 1 when manufacturing the pillow type bag B1 will be described.

  When the pull-down belt mechanisms 52 and 52 are driven, the sheet-like film F is fed out from the film roll of the film supply unit 6 and sent to the forming mechanism 51. In the forming mechanism 51, the sheet-like film F is wound around the outer surface of the tube 11a while passing through the gap between the former 11b and the tube 11a to form a tubular film Fc. The tubular film Fc is conveyed downward along the outer surface of the tube 11a by the pull-down belt mechanisms 52 and 52. When the sheet-like film F is wound around the tube 11a, both edges in the horizontal direction are superposed in the vertical direction. In the vertical sealing mechanism 53, the overlapping portion of the tubular film Fc is heat-sealed in the vertical direction. Thereafter, the tubular film Fc passes through the tube 11 a and descends to the lateral seal mechanism 56. At this time, the article C falls from the combination weighing machine 2 through the tube 11a into the cylindrical film Fc. Note that the control unit 7 instructs the control unit (not shown) of the combination weighing machine 2 to drop the article C at an appropriate timing.

  In the horizontal sealing mechanism 56, the first sealing jaws 61a, 61b,... Heat seal the cylindrical film Fc in the horizontal direction in a state where the article C is present in the cylindrical film Fc, and the top of the preceding bag B1. The seal portion SL1 and the lower seal portion SL2 of the subsequent bag B1 are formed simultaneously. At this time, the preceding bag B1 and the subsequent bag B1 (tubular film Fc) are separated by the cutter built in the first seal jaws 61a and 61b.

(3-2) Manufacturing Operation of Flat Bottom Bag The operation of the bag making and packaging machine 1 when manufacturing the flat bottom bag B2 will be described.

  When the pull-down belt mechanisms 52 and 52 are driven, the sheet-like film F is fed out from the film roll of the film supply unit 6 and sent to the forming mechanism 51. In the forming mechanism 51, the sheet-like film F is wound around the outer surface of the tube 11a while passing through the gap between the former 11b and the tube 11a to form a tubular film Fc. The tubular film Fc is conveyed downward along the outer surface of the tube 11a by the pull-down belt mechanisms 52 and 52. When the sheet-like film F is wound around the tube 11a, both edges in the horizontal direction are superposed in the vertical direction. In the vertical sealing mechanism 53, the overlapping portion of the tubular film Fc is heat-sealed in the vertical direction. Thereafter, the tubular film Fc passes through the tube 11 a and descends to the guide mechanism 54 and the lateral seal mechanism 56.

  When the tubular film Fc reaches the mechanisms 54 and 56, the tubular film Fc is first spread from the inside to the left and right by the spreaders 47 and 47. As a result, the shape of the tubular film Fc in the vicinity of the lower part of the spreaders 47, 47 becomes a flat shape that is pushed and spread in the left-right direction. When the tubular film Fc reaches both the mechanisms 54, 56, the guide members 41, 41 are in the open state shown in FIG. 6 (the leg tip portions 41a,... 5 in a closed state as shown in FIG. Therefore, the operations of the spreaders 47 and 47 that push the tubular film Fc in the left-right direction are not hindered by the operations of the guide members 41 and 41 that push the tubular film Fc in the front-rear direction.

  Subsequently, the sealing surfaces 30a and 30b of the second sealing jaws 62a and 62b perform heat sealing while sandwiching the tubular film Fc having a shape that is pushed and spread in the lateral direction in the lateral direction. The second seal jaws 62a and 62b simultaneously form the upper seal portion SL1 of the preceding bag B2 and the lower seal portion SL2 of the subsequent bag B2 by one sandwiching operation. Then, the preceding bag B2 and the succeeding bag B2 (tubular film Fc) are separated by a built-in cutter while heat-sealing the tubular film Fc. At this time, as described above, the upper seal portion SL1 of the preceding bag B2 has a wave shape in the short direction over the entire region. On the other hand, four flat portions FPE, FPN,... Are formed in the lower seal portion SL2 of the subsequent bag B2.

  After the succeeding bag B2 and the preceding bag B2 are separated, the bottom FB of the succeeding bag B2 is formed. Specifically, first, the pressing mechanisms 45, 45 move in the directions of arrows D1, D1 (see FIG. 16) to press the pressing portions 43, 43. Then, as described above, the pressing force is transmitted to the guide members 41 and 41 via the transmission mechanisms 44 and 44. As a result, the guide members 41, 41 are in an open state, and the four leg tip portions 41a,... Are formed from the inner side in the front-rear direction (arrows) at the four corners of the bottom portion FB of the bag B2. D2 and D2 direction (see FIG. 17). Thereby, the depth dimension L of the bag B2 is determined, and the substantially rectangular shape of the bottom portion FB of the bag B2 is stably formed. When the guide members 41 and 41 are in an open state and the tubular film Fc is spread in the front-rear direction, the spreaders 47 and 47 are inward in the left-right direction by the tubular film Fc that is pushed and spread in the front-rear direction. Pressed and deformed flexibly. That is, the spreaders 47 and 47 play a role of spreading the tubular film Fc in the left-right direction, but do not hinder the operation of the guide members 41 and 41 that push the tubular film Fc in the front-rear direction.

  Subsequently, the bottom plate 50 moves in the direction of arrow D3 (see FIG. 18) from the first retracted position (position of FIG. 5) to the first forward position (position of FIG. 6). As a result, the state shown in FIG. That is, the bottom plate 50 pushes down the lower seal portion SL2 in the direction (front-rear direction) intersecting with the direction (left-right direction) in which the lower seal portion SL2 extends, and bends the lower seal portion SL2 with respect to the lower portion of the bag body portion FL2. A lower bag FA is formed on the film Fc.

  Specifically, the left blade portion 50b and the right blade portion 50c of the bottom plate 50 contact the vicinity of the left and right ends of the lower seal portion SL2, respectively, and push down the vicinity of the left and right ends. As a result, the entire lower seal portion SL2 is bent with respect to the lower portion of the bag body portion FL2, and contacts the lower portion of the bag body portion FL2. Note that the vicinity of the left and right end portions of the lower seal portion SL2 is the vicinity of the end portion of the lower seal portion SL2 in the direction in which the lower seal portion SL2 extends (left and right direction) and is included in the vicinity portions CP1 and CP1. .

  On the other hand, the side plates 81 and 81 move to the second forward position (the position extending in the horizontal direction in FIG. 20C) with the bottom plate 50 in the first forward position in FIG. As a result, the state shown in FIG. That is, the side plates 81 and 81 heat-seal while pushing the side portions EP and EP of the bag lower portion FA in the direction (left and right direction) in which the lower seal portion SL2 extends and bending the side portions EP and EP with respect to the neighboring portions CP1 and CP1. By doing so, bottom FB of bag B2 is formed in cylindrical film Fc. As a result, the seal end portions SLE and SLE of the lower seal portion SL2 are heat-sealed while being bent with respect to the seal vicinity portions SLN and SLN.

  Specifically, the support members 82 and 82 move obliquely downward toward the side portions EP and EP in the directions of arrows D4 and D4 (see FIG. 19), respectively. As a result, the side plates 81 and 81 also move from the second retracted position (position shown in FIG. 20A) to the second intermediate position (position extending obliquely in FIG. 20C). Subsequently, the side plates 81 and 81 rotate upward around the rotation shafts 84 and 84 in a state where the bottom plate 50 is at the first forward position in FIG. 2 Move to the forward position. As a result, the state shown in FIG. 22 is obtained, and the side plates 81 and 81 in the second forward position and the lower end surfaces of the receiving bases 46b and 46b are in contact with each other with the bottom portion FB of the bag B2 interposed therebetween. At this time, the left blade portion 50b and the right blade portion 50c of the bottom plate 50 enter the recesses 81b and 81b of the side plates 81 and 81, respectively. Therefore, although the bottom plate 50 exists between the side plates 81 and 81 and the lower end surfaces of the pedestals 46b and 46b, the film F between the side plates 81 and 81 and the lower end surfaces of the pedestals 46b and 46b is sandwiched. Does not interfere with contact. At this time, the side plates 81 and 81 push down the side portions EP and EP along the left and right edges of the bottom plate 50 at the first forward position in FIG. As a result, as shown in FIG. 21B, the left blade portion 50b and the right blade portion 50c of the bottom plate 50 are surrounded by the side portions EP and EP of the bottom portion FB of the bag B2 and the adjacent portions CP1 and CP1. . The side parts EP and EP and the neighboring parts CP1 and CP1 are in contact with each other only at a position on the inner side in the left-right direction with respect to the blade parts 50b and 50c. This is because the side portions EP and EP and the neighboring portions CP1 and CP1 cannot contact each other at the position where the blade portions 50b and 50c exist. The contact portions between the side portions EP and EP and the adjacent portions CP1 and CP1 are heat sealed by the residual heat of the heat sealing operation by the lateral seal mechanism 56. Accordingly, the blade portions 50b and 50c are in a state of penetrating in the front-rear direction through gaps formed between the side portions EP and EP and the neighboring portions CP1 and CP1, respectively.

  Further, the side plates 81 and 81 are heat-sealed when the side portions EP and EP are heat-sealed while being bent with respect to the vicinity portions CP1 and CP1, that is, the seal end portions SLE and SLE are bent with respect to the seal vicinity portions SLN and SLN. When doing so, the flat portion FPE of the left seal end SLE and the flat portion FPN of the left seal vicinity SLN face each other and heat-seal, and the flat portion FPE of the right seal end SLE and the right seal vicinity SLN The flat portion FPN of the two faces each other and heat-seal. As a result, in the flat portions FPE, FPN,..., The seal end portions SLE, SLE and the seal vicinity portions SLN, SLN are firmly welded.

  Further, in a state where the bottom plate 50 is in the first forward position and the side plates 81 and 81 are in the second forward position, that is, in a state where the bottom plate 50 and the side plates 81 and 81 are pressing the bottom portion FB from below, A mass of the article C falls from the combination weighing machine 2. Therefore, the lower seal portion SL2 of the bottom portion FB is not damaged by the impact of the drop of the article C. Note that the control unit 7 instructs the control unit (not shown) of the combination weighing machine 2 to drop the article C at an appropriate timing.

  Thereafter, the bottom plate 50 moves backward from the first forward movement position, and the side plates 81, 81 move backward to the second forward movement position with a delay. Subsequently, the tubular film Fc is further conveyed downward, the upper seal portion SL1 of the bag B2 is formed by the lateral seal mechanism 56, and is separated from the next bag B2.

(4) Features of the bag making and packaging machine according to the present embodiment (4-1)
In the above embodiment, the corrugated portions WA and WB having a corrugated cross section in the short direction of the seal surfaces 30a and 30b on the seal surfaces 30a and 30b of the second seal jaws 62a and 62b, and the seal surfaces 30a and 30b, Flat portions FA1, FA2, FB1, FB2,... Having a flat cross section in the short direction of 30b are formed. Flat portions FA1, FA2, FB1, FB2,... Are formed at positions on the seal surfaces 30a, 30b that sandwich the seal end portions SLE, SLE of the lower seal portion SL2 and the seal vicinity portions SLN, SLN. That is, the seal ends SLE and SLE of the lower seal portion SL2 and the seal vicinity portions SLN and SLN are sandwiched by flat portions FPE, FPN,... (Flat portions FA1, FA2, FB1, FB2. Part) is formed. The flat portions FPE, FPN,... Of the lower seal portion SL2 are shorter than the other portions of the lower seal portion SL2 (portions sandwiched between the wave-shaped portions WA and WB and thermally sealed). It has a gently curved cross section in the direction. Then, the flat portions FPE and FPE of the seal end portions SLE and SLE of the lower seal portion SL2 and the flat portions FPN and FPN of the seal vicinity portions SLN and SLN face each other and are heat-sealed. Therefore, the seal end portions SLE and SLE of the lower seal portion SL2 and the vicinity thereof are more firmly welded. Therefore, the bottom portion FB of the flat bottom bag B2 can be stably formed.

(4-2)
In the above embodiment, the flat portions FA1, FA2, FB1, FB2,... Are not formed at positions where the upper seal portion SL1 is interposed between the seal surfaces 30a, 30b, but are formed at positions where the lower seal portion SL2 is interposed. Is done. That is, the lower seal portion SL2 is formed with flat portions FPE, FPN,..., But the upper seal portion SL1 is flat in the short direction like the flat portions FPE, FPN,. A portion having a simple cross section is not formed. Therefore, the upper seal portion SL1 is firmly heat-sealed, and the sealing performance of the upper seal portion SL1 is maintained.

(4-3)
In the above embodiment, the wave surfaces WA1, WB and the flat portions FA1, FA2, FB1, FB2... Are located at positions where the seal central portion SLC of the lower seal portion SL2 is sandwiched among the seal surfaces 30a, 30b. Only the mold parts WA and WB are formed. Note that the seal center portion SLC is a portion of the lower seal portion SL2 that is closer to the center than the seal vicinity portions SLN and SLN. In other words, the flat portions FA1, FA2, FB1, FB2,... Are not formed at positions where the seal central portion SLC is sandwiched between the seal surfaces 30a and 30b. That is, a portion having a flat cross section in the short direction of the lower seal portion SL2 such as the flat portions FPE, FPN,... Is not formed in the seal center portion SLC. Therefore, the seal center portion SLC of the lower seal portion SL2 is firmly heat-sealed, and the sealing performance of the lower seal portion SL2 is maintained.

(4-4)
In the above embodiment, the second bending mechanism 58 does not hold a heat source such as a heater for heat-sealing the seal end portions SLE, SLE and the seal vicinity portions SLN, SLN. Accordingly, the heat sealing between the seal end portions SLE and SLE and the seal vicinity portions SLN and SLN by the second bending mechanism 58 is performed by the heat generated by the horizontal seal mechanism 56 remaining in the seal end portions SLE and SLE and the seal vicinity portions SLN and SLN. This is done by the residual heat of the seal. However, due to the presence of the flat portions FA1, FA2, FB1, FB2,..., The weldability between the seal end portions SLE and SLE and the seal vicinity portions SLN and SLN is sufficiently maintained even in heat sealing by residual heat. It is supposed to be.

(5) Modification (5-1)
In the said embodiment, flat part FA1, FA2, FB1, FB2, ... has a flat shape in the cross sectional view of the transversal direction of the sealing surfaces 30a and 30b. Further, the flat portions FA1, FA2, FB1, FB2,... Are the seal end portions SLE, SLE of the seal surfaces 30a, 30b and the seal vicinity portions facing when the seal end portions SLE, SLE are bent. It is formed at a position sandwiching both SLN and SLN.

  However, the shapes of the flat portions FA1, FA2, FB1, FB2,... Do not have to be completely flat in the cross-sectional view of the seal surfaces 30a, 30b in the short direction, and the corrugated portions WA, WB. It may be any more gently curved shape. Further, the positions of the flat portions FA1, FA2, FB1, FB2,... Are the seal faces facing when the seal end portions SLE, SLE and the seal end portions SLE, SLE of the seal faces 30a, 30b are bent. It suffices if it is located at least one of the neighboring portions SLN and SLN.

(5-2)
Flat portions FA1, FA2, FB1, FB2,... Of the seal surfaces 30a, 30b of the second seal jaws 62a, 62b may have shapes as shown in FIGS.

  That is, flat portions FA1, FA2,... Of the sealing surface 30a of the second seal jaw 62a on the rear side are retracted to the bottom of the corrugated portion WA. On the other hand, flat portions FA1, FB2,... Of the sealing surface 30b of the second seal jaw 62b on the front side protrude to the height of the peak of the corrugated portion WB. Then, the flat portions FPE, FPE, FPN, FPN of the lower seal portion SL2 sandwiched between the flat portions FA1, FA2, FB1, FB2,... Protrude to the rear side of the lower seal portion SL2. Subsequently, since the bottom plate 50 is disposed behind the tubular film Fc, when the lower seal portion SL2 is bent by the bottom plate 50, the flat portions FPE, FPE, FPN, and FPN protrude downward. become. Therefore, when the side portions EP and EP of the bag lower FA are bent by the side plates 81 and 81, the surfaces on the protruding side of the flat portions FPE, FPE, FPN and FPN face each other. As a result, the flat portions FPE, FPE, FPN, and FPN are more easily brought into contact with each other, and the bottom FB of the bag B2 is more stably formed.

DESCRIPTION OF SYMBOLS 1 Bag making packaging machine 30a, 30b Sealing surface 51 Molding mechanism 52 Pull-down belt mechanism 53 Vertical sealing mechanism 54 Guide mechanism 56 Horizontal sealing mechanism 57 First folding mechanism 58 Second folding mechanism 62a, 62b Second sealing jaws FA1, FA2, FB1 , FB2 Flat part WA, WB Wave part B2 Flat bottom type bag SL1 Upper seal part SL2 Lower seal part FA Bag lower part FB Bottom part SLC Seal center part SLE Seal side part SLN Seal vicinity part FPE, FPN Flat part

JP 2000-335511 A JP 2000-177715 A

Claims (6)

A bag making and packaging machine for manufacturing a bag having a main body portion that encloses an object to be packaged, and upper and lower upper and lower seal portions of the main body portion,
A horizontal sealing mechanism having a pair of sealing surfaces that heat-seal while sandwiching a cylindrical packaging material in the horizontal direction and form the upper seal portion and the lower seal portion;
A first folding mechanism that bends the lower seal portion of the tubular packaging material in a direction intersecting the lower seal portion and forms a lower portion of the bag including the lower seal portion and a part of the main body portion;
A second bending mechanism for heat-sealing while bending a lateral end portion of the lower seal portion with respect to a vicinity portion of the lower seal portion adjacent to the end portion;
With
Each of the pair of seal surfaces includes a first portion having a first curved shape and a second portion having a second curved shape that is gentler than the first curved shape;
The second portion of the pair of sealing surfaces is heat-sealed while sandwiching at least a part of at least one of the end portion and the vicinity portion of the lower seal portion,
Bag making and packaging machine. The second portion of the pair of sealing surfaces is heat-sealed while sandwiching at least a part of both the end portion and the vicinity portion of the lower seal portion,
The second bending mechanism is configured to fold at least a portion of the end portion and the vicinity portion sandwiched by the second portion and heat-sealed while bending the end portion of the lower seal portion with respect to the vicinity portion. Face to face and heat seal both
The bag making and packaging machine according to claim 1. The second curved shape is a substantially flat shape.
The bag making and packaging machine according to claim 1 or 2. The pair of sealing surfaces are heat-sealed while sandwiching the cylindrical packaging material in the lateral direction, and the upper seal portion of the preceding bag of the two bags produced continuously and the lower portion of the subsequent bag Forming the seal part at the same time,
The second portion is not formed at a position where the upper seal portion of the preceding bag is sandwiched between the pair of seal surfaces, and is formed at a position where the lower seal portion of the subsequent bag is sandwiched. Yes,
The bag making and packaging machine according to any one of claims 1 to 3. Of the pair of sealing surfaces, only the first part of the first part and the second part is formed at a position sandwiching the central part closer to the center than the vicinity of the lower seal part. ,
The bag making and packaging machine according to any one of claims 1 to 4. The second bending mechanism is configured to heat-seal the end portion of the lower seal portion with respect to the vicinity portion, while the end portion is heat-sealed with respect to the vicinity portion by residual heat at the time of heat sealing by the lateral seal mechanism.
The bag making and packaging machine according to any one of claims 1 to 5.

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