Bag making apparatus

Abstract

Provided is a bag making apparatus with a simple configuration that: prevents fluctuations in tension, slippage of seal positions, and meandering or skewing of a web of film; allows the setting of precise initial conditions; reduces or makes unnecessary monitoring, and time and structures for adjustment; allows increased feed rate; and improves production efficiency. The bag making apparatus for packaging containers comprises: a tension control unit for controlling the continuous feed rate according to the values detected by a tension sensor of a tension detection roll; an optical detection unit for simultaneously recognizing multiple marks provided on the surface of the web of film at the respective positions thereof; a skewing correction unit; and a seal position correction unit for adjusting the positions of multiple sealing units in the feed direction.

Claims

1. A bag making apparatus, comprising: a continuous feed mechanism having a continuous feed roll continuously feeding a web of film; an intermittent feed mechanism having an intermittent feed roll intermittently feeding the web of film; a feed adjustment mechanism having a reciprocally movable dancer roll between the continuous feed mechanism and the intermittent feed mechanism; and a sealing mechanism sealing predetermined portions of the web of film fed by the intermittent feed mechanism, wherein the feed adjustment mechanism includes a swinging drive unit for the dancer roll, a tension detection roll provided upstream of the dancer roll, a tension sensor detecting tension on the tension detection roll, and a tension control unit configured to control a feed speed of the continuous feed roll in accordance with a detection value of the tension sensor, wherein the intermittent feed mechanism includes an optical detection unit configured to recognize a plurality of marks on a surface of the web of film simultaneously at respective positions, a unit configured to adjust an intermittent feed amount, and a skew correction unit configured to correct a displacement of the web of film in a direction perpendicular to a feed direction, wherein the sealing mechanism includes a plurality of sealing units provided in a section where the web of film is intermittently fed, and a seal position correction unit configured to adjust positions in the feed direction of the plurality of sealing units in accordance with positions of the marks in the feed direction of the web of film which are recognized by the optical detection unit, and wherein the swinging drive unit is set to move the dancer roll reciprocally in a predetermined range, and the tension control unit outputs a signal to the swing drive unit to change a swing end position of the swinging drive unit based on varying detection values of the tension sensor such that variation in the detection values of the tension sensor is reduced.

2. The bag making apparatus according to claim 1, wherein the tension detection roll is fixed in position such that it is not movable other than being rotatable about its own axis, and the tension sensor is configured to detect a force applied to a rotation shaft of the tension detection roll.

3. The bag making apparatus according to claim 1, wherein the swinging drive unit is set to move the dancer roll reciprocally at a predetermined speed and in a predetermined range, and the tension control unit controls the feed speed of the continuous feed roll based on varying detection values of the tension sensor such that the detection values of the tension sensor remain around a predetermined value.

4. The bag making apparatus according to claim 1, wherein the tension control unit lowers a continuous feed speed of the continuous feed mechanism when the moving range of the swinging drive unit is increased, and raises the feed speed of the continuous feed mechanism when the moving range of the swinging drive unit is decreased.

5. The bag making apparatus according to claim 1, wherein either: (a) the tension control unit controls the swinging drive unit in consideration of information on positions of the marks in the feed direction of the web of film which are recognized by the optical detection unit, (b) the tension control unit controls the feed speed of the continuous feed roll in further consideration of information on positions of the marks in the feed direction of the web of film which are recognized by the optical detection unit, or (c) the tension control unit controls the swinging drive unit in consideration of information on positions of the marks in the feed direction of the web of film which are recognized by the optical detection unit and controls the feed speed of the continuous feed roll in further consideration of information on positions of the marks in the feed direction of the web of film which are recognized by the optical detection unit.

6. The bag making apparatus according to claim 5, wherein the tension control unit changes a predetermined value around which detection values of the tension sensor are to remain when there is a displacement in the positions of the marks in the feed direction of the web of film which are recognized by the optical detection unit which is larger than a predetermined displacement.

7. The bag making apparatus according to claim 1, wherein the optical detection unit includes a plurality of two-dimensional optical sensors provided above the intermittent feed mechanism and spaced apart in the feed direction, and is configured to be able to detect two-dimensional positions of the marks provided on the surface of the web of film when the web of film is at halt.

8. The bag making apparatus according to claim 7, wherein the feed amount adjustment unit is configured to determine a feed amount for one intermittent feed in accordance with information on the positions of the marks in the feed direction of the web of film which are recognized by the plurality of two-dimensional optical sensors.

9. The bag making apparatus according to claim 7, wherein the seal position correction unit is configured to adjust spacing between the plurality of sealing units in the feed direction in accordance with information on the positions of the marks in the feed direction of the web of film which are recognized by the plurality of two-dimensional optical sensors.

10. The bag making apparatus according to claim 7, wherein the plurality of two-dimensional optical sensors are spaced apart by a distance corresponding to a feed amount of several intermittent feeds of the web of film.

11. The bag making apparatus according to claim 1, wherein the intermittent feed mechanism further comprises at least one additional intermittent feed roll, such that the intermittent feed mechanism comprises a plurality of intermittent feed rolls, and the skew correction unit is configured to turn at least one of the intermittent feed rolls around an axial line passing a center in the width direction of the web of film and extending perpendicularly to the web of film.

12. The bag making apparatus according to claim 11, wherein the skew correction unit is configured to turn the plurality of intermittent feed rolls in accordance with a relative displacement of a printed pattern on the web of film in a direction perpendicular to the feed direction recognized by the plurality of two-dimensional optical sensors.

13. The bag making apparatus according to claim 1, wherein the seal position correction unit is formed by a rack rail extending in the feed direction of the web of film, a pinion gear provided to each sealing unit to mesh with the rack rail, and a pinion drive motor provided for each sealing unit to drive the pinion gear.

14. The bag making apparatus according to claim 1, wherein the intermittent feed mechanism is configured to intermittently feed upper and lower webs of film with a bottom material interposed between the two webs of film, and the sealing mechanism is configured to seal the bottom material together with the two, upper and lower, webs of film.

15. The bag making apparatus according to claim 1, wherein a cutting mechanism is provided downstream of the intermittent feed mechanism to cut the web of film after sealing to separate the web of film into discrete pouch containers.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a plan view of a bag making apparatus in one embodiment of the present invention;

(2) FIG. 2 is a side view of the bag making apparatus in one embodiment of the present invention;

(3) FIG. 3 is a schematic diagram for explaining the operation of the bag making apparatus in one embodiment of the present invention;

(4) FIG. 4 is a schematic diagram for explaining a feed adjustment mechanism of the bag making apparatus in one embodiment of the present invention;

(5) FIG. 5 is a schematic diagram for explaining optical detection unit of the bag making apparatus in one embodiment of the present invention;

(6) FIG. 6 is a front view of an intermittent feed roll of the bag making apparatus in one embodiment of the present invention;

(7) FIG. 7 is a plan view of the intermittent feed roll of the bag making apparatus in one embodiment of the present invention;

(8) FIG. 8 is a side view of the intermittent feed roll of the bag making apparatus in one embodiment of the present invention;

(9) FIG. 9 is a front view of sealing unit of the bag making apparatus in one embodiment of the present invention;

(10) FIG. 10 is a plan view of the sealing unit of the bag making apparatus in one embodiment of the present invention; and

(11) FIG. 11 is a side view of the sealing unit of the bag making apparatus in one embodiment of the present invention.

EXPLANATION OF REFERENCE NUMERALS

(12) 100: bag making apparatus

(13) 110: continuous feed mechanism

(14) 111: continuous feed roll

(15) 112: splitting mechanism

(16) 113: continuous feed motor

(17) 120: intermittent feed mechanism

(18) 121: intermittent feed roll

(19) 122: intermittent feed motor

(20) 123: intermittent feed pressing roll

(21) 124: intermittent feed roll support table

(22) 125: fixing bolt

(23) 126: film holder

(24) 127: placement piece

(25) 130: feed amount adjustment unit

(26) 140: optical detection unit

(27) 141: front-side two-dimensional optical sensor

(28) 142: rear-side two-dimensional optical sensor

(29) 150: skew correction unit

(30) 151: rotation support shaft

(31) 152: skew correction motor

(32) 153: eccentric cam

(33) 154: base table

(34) 160: feed adjustment mechanism

(35) 161: dancer roll

(36) 162: swinging drive unit

(37) 163: tension detection roll

(38) 164: tension sensor

(39) 165: tension control unit

(40) 166: superposing roll

(41) 170: sealing mechanism

(42) 171: sealing unit

(43) 172: upper frame

(44) 173: lower frame

(45) 174: slide rail

(46) 175: slider

(47) 177: drive beam

(48) 178: upper heat seal part

(49) 179: lower heat seal part

(50) 180: seal position correction unit

(51) 181: pinion gear

(52) 182: rack rail

(53) 183: pinion drive motor

(54) 184: seal unit drive shaft

(55) 190: cutting mechanism

(56) F: web of film

(57) M: mark

(58) R: material roll

(59) B: bottom material

BEST MODE FOR CARRYING OUT THE INVENTION

(60) The bag making apparatus according to the present invention includes a continuous feed mechanism having a continuous feed roll continuously unwinding a rolled web of film and feeding the web of film at a predetermined speed, an intermittent feed mechanism having an intermittent feed roll for intermittently feeding the web of film by a predetermined amount, a feed adjustment mechanism provided between the continuous feed mechanism and the intermittent feed mechanism and including a reciprocally movable dancer roll, and a sealing mechanism sealing predetermined portions of at least two, upper and lower, webs of film fed by the intermittent feed mechanism.

Embodiments

(61) FIG. 1 and FIG. 2 are an overall plan view and side view of a bag making apparatus in one embodiment of the present invention, and FIG. 3 is a schematic diagram generally showing the operation of the apparatus.

(62) The bag making apparatus 100 in one embodiment of the present invention is configured to continuously produce pouch containers by continuously unwinding a material roll R and feeding the web of film F successively to a continuous feed mechanism 110, a feed adjustment mechanism 160, an intermittent feed mechanism 120, and a cutting mechanism 190.

(63) The web of film F is rolled and supplied as a material roll R in the continuous feed mechanism 110. The material roll R is axially supported to rotate around a horizontal axis, while an axially supported continuous feed roll 111 is configured to be driven around a vertical axis. The web of film F drawn out horizontally passes over a plurality of inclined guide rolls to change its direction to run along a vertical plane to be fed to the continuous feed roll 111.

(64) Downstream of the continuous feed roll 111 is provided a splitting mechanism 112 that continuously splits the web of film F at its center into two, upper and lower, webs of film. The two, upper and lower, split webs of film F change direction to run along a horizontal plane again by the splitting mechanism 112 to be fed to the downstream feed adjustment mechanism 160.

(65) In the feed adjustment mechanism 160, the two, upper and lower, webs of film F fed from the continuous feed mechanism 110 travel along upper and lower paths distanced from and symmetrical with each other, and are superposed at the most downstream end by superposing rolls 166, to be fed to the intermittent feed mechanism 120 to be described later.

(66) In the upper and lower, spaced apart and symmetrical paths of this feed adjustment mechanism 160 are each provided, as shown in FIG. 3 and FIG. 4, a tension detection roll 163, and a reciprocally movable dancer roll 161, so as to absorb slack in the web of film F that is caused by periodic fluctuations in the feed amount between the continuous feed and the intermittent feed and to reduce tension fluctuations.

(67) The tension detection rolls 163 are axially supported to rotate only, and configured to determine the tension of the web of film F by detecting the force applied on the rotation shaft by a tension sensor 164.

(68) In this embodiment, bottom material B is supplied before the superposing rolls 166 to be superposed at both lateral edges of the upper and lower webs of film F such as to be interposed between the two webs of film F.

(69) The intermittent feed mechanism 120 is configured to intermittently feed the two, upper and lower, webs of film F with the bottom material B interposed therebetween by a predetermined amount, with an intermittent feed roll 121 disposed at the most downstream end.

(70) The upper and lower webs of film F with the bottom material B interposed between the two webs of film F are kept horizontal between the intermittent feed roll 121 of the intermittent feed mechanism 120 and the superposing rolls 166, and sealed at both lateral edges and crossing portions extending in the width direction and spaced apart at predetermined intervals, by unit of a sealing mechanism 170 having a plurality of sealing unit 171 disposed in this section.

(71) A front-side two-dimensional optical sensor 141 and a rear-side two-dimensional optical sensor 142 are provided at upstream and downstream positions of this section, respectively, which are connected to optical detection unit 140 so that marks on the surface of the web of film F can be detected simultaneously.

(72) On the downstream side of the most downstream intermittent feed roll 121 of the intermittent feed mechanism 120 is disposed the cutting mechanism 190, where the web of film is cut and separated into discrete pouch containers P.

(73) While the intermittent feed roll 121 is located most downstream in the intermittent feed mechanism 120 in the illustration shown in FIG. 3, another intermittent feed roll may be provided upstream and operated in coordination, and a few other such rolls may further be provided at suitable locations.

(74) In the apparatus of this embodiment configured generally as described above, in the section where the upper and lower webs of film F with the bottom material B interposed between the two webs of film F are sealed at both lateral edges and crossing portions extending in the width direction and spaced apart at predetermined intervals, the tension on the web of film F is affected by the drive speed of the continuous feed roll 111, the speed, range, and timing of the reciprocal movement of the dance roll 161, and the drive speed and timing of the intermittent feed roll 121, and the elongation of the web of film F fluctuates with the tension.

(75) Moreover, tension fluctuations and vibration during the transfer of the web of film F, or vibration of the entire apparatus may cause the web of film F to wander or skew.

(76) In this embodiment, therefore, the apparatus has configurations that absorb tension fluctuations and determine the elongation of the web of film F so as to allow adjustment of the apparatus, whereby tension and elongation variations are reduced and stable operation is achieved, and that correct a bend or skew in the web of film F and prevent displacement in position of the seals caused by tension fluctuations, or wandering or skewing of the web of film. These configurations will be described below.

(77) Tension control operation in the feed adjustment mechanism 160 will be described with reference to FIG. 4 (which is simplified for the sake of explanation).

(78) The intermittent feed roll 121 intermittently feeds the web of film F under predetermined tension by a preset pitch (to be described later), which is detected by the optical detection unit 140 downstream of the feed adjustment mechanism 160. The drive speed and timing of the intermittent feed roll 121 are set in feed amount adjustment unit 130, and the speed, range, and timing of the reciprocal movement of the dancer roll 161, and the drive speed of the continuous feed roll 111, are set in tension control unit 165, in accordance with the settings in the feed amount adjustment unit 130.

(79) The feed amount adjustment unit 130 controls an intermittent feed motor 122 to drive the intermittent feed roll 121 at the preset drive speed and with the preset timing.

(80) The tension control unit 165 controls swinging drive unit 162 to cause the dancer roll 161 to move reciprocally with the preset speed, range, and timing, and controls a continuous feed motor 113 to drive the continuous feed roll 111 at the preset drive speed.

(81) Once the driving starts, the tension control unit 165 performs feedback control such as PID, wherein it increases output signals instructing the drive speed of the continuous feed motor 113 in response to an increase in input signals from the tension sensor 164, and decreases the output signals in response to a decrease in the input signals, so that the average value of the input signals remains at a predetermined value. This allows for adjustment of tension without the influence of moment of inertia and friction, so that tension fluctuations are minimized even when the web of film is being fed at high speed.

(82) The tension control unit 165 may output signals instructing the timing for switching the moving direction at both ends of the moving range of the swinging drive unit 162 in response to signal inputs from the tension sensor 164, with feedback control such as PID to minimize the difference between the maximum and minimum values of the input signals. This can further reduce the tension fluctuations caused by a difference in the timing between the intermittent drive of the intermittent feed roll 121 and the movement of the dancer roll 161.

(83) The feedback control method and various settings such as constants or gains used in control calculations may be suitably selected in consideration of the characteristics of the entire apparatus, operation speed of the controller, cost performance, and so on, as long as the average tension can be made to remain at a predetermined value.

(84) Also, information on the elongation of the web of film F detected by the optical detection unit 140 to be described later, and outputs from the tension sensor 164 may be processed and used in the feedback control. Tension fluctuations can further be reduced with the use of various sources of information on the tension.

(85) Next, the structure and operation of the optical detection unit 140 for recognizing a plurality of marks on the surface of the web of film F simultaneously at respective positions will be described with reference to FIG. 5 (which is simplified for the sake of explanation).

(86) The optical detection unit 140 is configured to display and process the image taken by the front-side two-dimensional optical sensor 141 and the rear-side two-dimensional optical sensor 142.

(87) The front-side two-dimensional optical sensor 141 and the rear-side two-dimensional optical sensor 142 are comprised of CCD cameras spaced apart from each other and disposed such as to be able to take an image of the surface of the web of film in the section where the web of film F is fed horizontally by the intermittent feed mechanism 120. Their positions are each set accurately relative to other constituent parts of the intermittent feed mechanism 120.

(88) When starting the production of pouch containers, the initial position for the intermittent feed is set first while the surface of the web of film F under tension is imaged by the rear-side two-dimensional optical sensor 142. An operator may perform this task while visually checking the taken image on the monitor, or the intermittent feed roll 121 may be controlled automatically based on the information detected by the optical detection unit 140.

(89) The web of film F under tension is imaged simultaneously by the front-side two-dimensional optical sensor 141 and the rear-side two-dimensional optical sensor 142 while the web of film F is at halt, and the positions of marks M are determined by the optical detection unit 140 from the captured images to detect the distance Ln between the pouch containers spaced apart by a plurality of pitches (n pitches). Dividing this distance produces one pitch L1 for one pouch container.

(90) The optical detection unit 140 outputs this calculated pitch L1 to the feed amount adjustment unit 130 as a feed amount for one intermittent feed.

(91) The positions of and spacing between the plurality of sealing unit 171 to be described later are also set in accordance with the calculated pitch L1.

(92) Since the two-dimensional optical sensors take a two-dimensional image, it is also possible to determine the positions of marks M in the width direction of the web of film F, so that the optical detection unit 140 detects a bend or skew in the web of film F based on the positional information and outputs a command for correction to skew correction unit 150 to be described later.

(93) With a plurality of two-dimensional optical sensors, the pitch L1 for one pouch container can be detected, as well as the position of the web of film in the width direction can be detected, by imaging the web of film F tensioned with the same conditions as in actual operation just once while the web of film F is at halt.

(94) Since the pitch L1 for one pouch container is obtained by dividing the distance Ln covering a plurality of pitches, the pitch L1 for one pouch container can be accurately calculated with a precision n times the resolution of the front-side two-dimensional optical sensor 141 and the rear-side two-dimensional optical sensor 142, so that the positions of and spacing between the plurality of sealing unit 171 to be described later can be precisely set, and the need to repeat test operation and inspection of pouch containers for each model change is obviated.

(95) For example, if based on detection with the use of only one two-dimensional optical sensor having a resolution of 0.1 mm, the sealing unit 171 at both ends, if there are arranged ten sealing unit 171, may be displaced by as much as 1 mm, which is the sum of ten pitches. With two two-dimensional optical sensors arranged at positions spaced apart by ten pitches, the sealing unit 171 at both ends spaced apart by ten pitches will be displaced by 0.1 mm at most under initial settings, which will be well within a tolerable range.

(96) It is also possible to calculate the positions through image processing of the two-dimensional image of characters or patterns necessary for the pouch containers, so that printing of specific marks M may be omitted.

(97) While two two-dimensional optical sensors are provided in this embodiment, a larger number of sensors may be provided.

(98) Next, the structure and operation of the skew correction unit 150 will be described with reference to FIG. 6 to FIG. 8.

(99) The skew correction unit 150 is configured to turn the intermittent feed roll 121 around an axial line passing the center in the width direction of the web of film F and extending perpendicularly to the web of film F.

(100) The intermittent feed roll 121 is supported on an intermittent feed roll support table 124 rotatably and driven to rotate by the intermittent feed motor 122 secured on the intermittent feed roll support table 124.

(101) Above the intermittent feed roll 121 is provided an intermittent feed pressing roll 123 so that the web of film F is sandwiched between the intermittent feed roll 121 and the intermittent feed pressing roll 123 and fed intermittently.

(102) In the illustrated embodiment, a film holder 126 is further provided downstream of the intermittent feed roll 121 on the intermittent feed roll support table 124 so that tension and other parameters can be adjusted also on the downstream side.

(103) The skew correction unit 150 is configured by the intermittent feed roll support table 124 being supported on a base table 154 provided on a stationary side such as to be able to turn via a rotation support shaft 151.

(104) The rotation support shaft 151 is provided at the center in the width direction of the intermittent feed roll 121 and directly below the rotation center axis.

(105) A skew correction motor 152 is provided on one side in the width direction of the base table 154. An eccentric cam 153 rotated by this skew correction motor 152 is configured to mesh with the intermittent feed roll support table 124. The intermittent feed roll support table 124 is thus configured to turn around the rotation support shaft 151 as the skew correction motor 152 is rotated in normal and reverse directions.

(106) The skew correction motor 152 of the skew correction unit 150 is controlled to turn the intermittent feed roll support table 124 to an angle necessary for correcting a displacement in the width direction of the web of film F, which is detected by the optical detection unit 140 described in the foregoing.

(107) On the upper surface of the base table 154 are a plurality of placement pieces 127, which support the weight of the intermittent feed roll support table 124 placed thereon such as to be slidable.

(108) The base table 154 and the intermittent feed roll support table 124 are configured such that their positional relationship can be restricted with fixing bolts 125. The support table may be allowed to turn, or secured in position, by changing the fastening degree of the fixing bolts 125. Since the intermittent feed roll support table 124 can turn only very slightly, i.e., 0.1° or less, the fixing bolts 125 may be fastened such as to allow the table to turn by its resilience.

(109) The configuration described above that allows turning of the intermittent feed roll 121 for skew correction enables correction of a skew in the web of film F without applying a large lateral force to the web of film F so that stability is improved. Thus, with the highly precise adjustment and reduced tension fluctuations, continuous operation is possible with higher precision and at higher speed.

(110) In the embodiment shown in FIG. 1 and FIG. 2, two intermittent feed rolls 121 are provided in the section of the intermittent feed mechanism 120. While the skew correction unit 150 may be provided at least to a most downstream intermittent feed roll 121, providing the skew correction unit 150 to both intermittent feed rolls 121 will enable even more precise skew correction substantially over the entire section of the intermittent feed mechanism 120.

(111) Next, the structure and operation of the seal position correction unit 180 will be described with reference to FIG. 9 to FIG. 11.

(112) The plurality of sealing unit 171 used in the sealing mechanism 170 in this embodiment are heat sealing unit configured to seal necessary portions of the web of film F and the bottom material B by thermal bonding. The heat sealing unit are disposed at an interval corresponding to the pitch L of the pouch containers so that the sealing unit 171 repeat thermal bonding several times at the same portions as the web of film is intermittently fed by the intermittent feed mechanism 120.

(113) FIG. 9 to FIG. 11 show one of the sealing unit 171 that form thermal bonds at portions of the web of film F extending in the width direction.

(114) The sealing unit 171 includes a lower frame 173 and an upper frame 172, each having a lower heat seal part 179 and an upper heat seal part 178 parallel to each other. The upper frame 172 is connected to a drive beam 177 to be movable in the feed direction of the web of film F, and moved up and down vertically to the lower frame 173. Thus the lower heat seal part 179 and the upper heat seal part 178 can sandwich the web of film F to form a thermal bond.

(115) Two slide rails 174 extend parallel to the feed direction of the web of film F over the entire section of the intermittent feed mechanism 120, and sliders 175 that are movable on the slide rails 174 are provided on the lower side of the lower frame 173, so that the sealing unit 171 can freely move in the feed direction of the web of film F.

(116) Two rack rails 182 extend parallel to the slide rails 174, with two pinion gears 181 meshing with the rack rails 182 and a pinion drive motor 183 for driving the pinion gears 181 provided on lateral ends below the lower frame 173, these forming the seal position correction unit 180.

(117) In this embodiment, the two pinion gears 181 are fixed to a sealing unit drive shaft 184 rotatably supported at lateral ends below the lower frame 173, and one end of the sealing unit drive shaft 184 is coupled to the pinion drive motor 183.

(118) With this configuration, the pinion drive motor 183 is driven in accordance with the pitch L1 of one pouch container calculated by the optical detection unit 140 as described above, to set the positions of and spacing between the plurality of sealing unit 171.

(119) As the rack rails 182 are secured in position at multiple points, a degradation of precision caused by deformation is prevented with a simple structure. As the pinion gears 181, as well as the pinion drive motor 183, sealing unit drive shaft 184, and other parts for driving the pinion gears, can be provided on lateral ends below the sealing unit to be exposed, the structure of the sealing unit 171 is simplified. Thus, while precision is maintained, the structure of the entire apparatus is made lighter and simpler to make the maintenance easy.

(120) The above described structure may be employed also for a crossing member that couples together the lower frames in the width direction in the sealing unit configured to seal both lateral edges in the feed direction of the web of film F (in the upstream-side sealing mechanism 170 shown in FIG. 1 and FIG. 2), to achieve the same advantageous effects.

(121) Although one embodiment of the present invention has been illustrated, the invention is not limited to this, and may have any other specific configurations, as long as: the feed adjustment mechanism includes swinging drive unit configured to move a dancer roll, a tension detection roll provided upstream of the dancer roll for the web of film to pass over, a tension sensor that detects a force on the tension detection roll, and tension control unit configured to control feed speed of the continuous feed roll in accordance with the detection value of the tension sensor; the intermittent feed mechanism includes optical detection unit configured to recognize a plurality of marks on a surface of the web of film simultaneously at respective positions, feed amount adjustment unit capable of adjusting a feed amount for one intermittent feed, and skew correction unit configured to correct a displacement of the recognized marks from an original position in a direction perpendicular to the feed direction of the web of film; and the sealing mechanism includes a plurality of sealing unit provided in a section where the web of film is intermittently fed by the intermittent feed mechanism, and seal position correction unit configured to adjust positions in the feed direction of the plurality of sealing unit in accordance with the positions of the marks in the feed direction of the web of film which are recognized by the optical detection unit.

INDUSTRIAL APPLICABILITY

(122) The bag making apparatus of the present invention is suited for producing pouch containers made of plastic film and formed into a bag shape by sealing, in particular, but not limited to apparatuses that make bags by sealing, and may also be applied to production apparatuses that perform various processing and treatment precisely to a continuously fed sheet-like material under stable tension.