Seal cutting device for bag making and filling machine

Abstract

To provide a seal cutting device for a bag making and filling machine that can cut a cylindrical packaging material well even if a packaging speed is changed.SOLUTION: A knife for cutting a cylindrical film is disposed on an anvil 14 which holds the cylindrical film between horns 15 and performs end sealing.The knife is moved back and forth by back and forth moving means between a standby position where a cutting edge does not protrude from a sealing surface 30b of the anvil 14, and a maximum protruding position where the cutting edge protrudes the most. Data input setting means for setting knife timing at which the knife reaches the maximum protrusion position by the back and forth moving means, and control means for calculating operation start timing from a standby position of the knife in one packaging cycle on the basis of the knife timing and a packaging speed are included. The control means controls the back and forth moving means so that the knife operates on the basis of the operation start timing and the knife timing regarding the maximum protrusion position.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a seal cutting device that cuts a tubular packaging material with a knife installed in a sealing body when the tubular packaging material is end-sealed in a bag making and filling machine. [Background technology]

[0002] In a bag making and filling machine, a seal cutting device is known which clamps a tubular film (tubular packaging material) with a pair of sealing bodies to apply an end seal in a direction intersecting the film transport direction and cuts the tubular film at the sealed location in a direction intersecting the film transport direction.The seal cutting device employs a so-called "cut-off" type cutting means in which a knife housed inside one of the sealing bodies protrudes from the sealing surface to cut the tubular film in time with the tubular film being clamped by the pair of sealing bodies (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 55-29862 Summary of the Invention [Problem to be solved by the invention]

[0004] In a seal cutting device using the above-mentioned "cut-off" type cutting means, in order to stably cut the tubular film, it is preferable to move the knife at a predetermined speed at a predetermined timing when the tubular film is clamped by the seal body. In a conventional seal cutting device, the timing to start the knife protruding operation is set according to the packaging conditions, and the knife is controlled according to the set protruding operation start timing. When the packaging speed (the number of packages that can be packaged per predetermined time) is changed to a high or low speed in a bag making and filling machine, the knife protruding operation start timing needs to be changed to a setting according to the packaging speed of the bag making and filling machine each time. In that case, the operator needs to find the timing at which the knife is sharp enough while checking the cutting status of the tubular film and reset the knife protruding operation start timing. In addition, if the knife protruding operation start timing is kept the same and the knife moving speed is changed according to the packaging speed, the slower the packaging speed becomes, the slower the moving speed when the knife cutting edge cuts through the tubular film becomes, which causes a problem that the tubular film cannot be cut well.

[0005] An object of the present invention is to provide a seal cutting device in a bag making and filling machine that can satisfactorily cut tubular packaging material even when the packaging speed is changed. [Means for solving the problem]

[0006] The seal cutting device in the bag making and filling machine according to claim 1 of the present application comprises: A seal cutting device for a bag making and filling machine, which clamps a tubular packaging material (10) between a pair of sealing bodies (14, 15) facing each other across a conveying path of the tubular packaging material (10) to seal the material in a direction intersecting the conveying direction, and cuts the tubular packaging material (10) by protruding a cutting edge (16a) of a knife (16) from one of the sealing bodies (14), an advance / retract movement means (17) for moving the knife (16) at a predetermined speed so that a cutting edge (16a) of the knife (16) appears and disappears from the sealing body (14) to cut the tubular packaging material (10); a sealer detection means (18) for detecting the operating position of the seal body (14, 15); a knife timing at which the blade tip (16a) protrudes most from the sealing body (14) at the timing when the sealing bodies (14, 15) clamp the tubular packaging material (10); A control means (20) is provided for calculating the timing at which the knife (16) starts to protrude in accordance with the wrapping speed and controlling the operation of the advancing and retreating movement means (17) so as to achieve the set knife timing. According to the invention of claim 1, by simply setting the knife timing at which the tip of the knife protrudes the most from the sealing body, the timing at which the knife protrusion operation starts is calculated in accordance with changes in the packaging speed and the knife operation is controlled, so that the operator does not need to reset the protrusion operation start timing each time in accordance with the packaging speed, and the tubular packaging material can be cut well at the appropriate timing that matches the timing at which the sealing body clamps the tubular packaging material.

[0007] In the invention according to claim 2, a knife driving servo motor (35) for driving the advancing and retreating movement means (17); and a knife detection means (39) for detecting the movement position of the knife (16). The knife timing at which the blade tip (16a) is at its most protruding position in relation to the operating position of the sealing body (14, 15) detected by the sealer detection means (18) is inputted numerically by a data input means (19). According to the invention of claim 2, the advance / retract movement means is configured to be operated by a servo motor, so the operation of the knife can be controlled with high precision. Also, the knife timing at which the blade tip is at the position most protruding from the seal body can be inputted as a numerical value, so the setting operation can be easily performed.

[0008] In the invention according to claim 3, a sealing servo motor (25) that rotates the pair of sealing bodies (14, 15) is provided, The knife (16) has a cutting edge (16a) housed and supported in the one of the seal bodies (14) so ​​that the cutting edge (16a) can be projected and retracted, and the advancing and retracting means (17) is connected to the knife (16). According to the invention of claim 3, a knife, the cutting edge of which is supported so as to be able to appear and disappear on one side of the sealing body rotated by a servo motor, is moved by the servo motor. Therefore, even in high-speed packaging, there is no delay in the knife operation in conjunction with the rotation of the sealing body, and the tubular packaging material can be cut accurately and satisfactorily.

[0009] In the invention according to claim 4, the one sealing body (14) is an anvil (14) that houses and supports the knife (16), and the other sealing body (15) is an ultrasonic sealing mechanism that is an ultrasonically vibrating horn (15), The forward and backward moving means (17) is a link mechanism (33) that allows the cutting edge (16a) of the knife (16) to protrude from and retract into the anvil (14); an operating rod (36) that is axially movably inserted into the hollow shaft (21) of the anvil (14) and has one end connected to the link mechanism (33); a servo motor (35) for driving the knife, which moves the operating rod (36) in the axial direction; The knife detection means (39) is arranged so as to be capable of detecting the position of the cutting edge (16a) of the knife (16) moved by the knife drive servo motor (35), and the sealer detection means (18) is arranged so as to be capable of detecting the rotational position of the sealing body (14, 15) caused by the sealing servo motor (25). According to the invention of claim 4, the sealing body and the knife are operated by a servo motor, and their rotational and moving positions are detected by a detection means, so that the rotational position of the sealing body and the moving position of the knife can be precisely controlled. In addition, the connected knife and the actuating rod are disposed inside the anvil, which is the other sealing body for the ultrasonically vibrating horn, so that the knife and the advancing and retreating moving means are not directly affected by the ultrasonic vibration, and the tubular packaging material can be cut well by the stable knife cutting action. In addition, it is possible to prevent wear and tear on the knife's operating mechanism and driving part caused by the ultrasonic vibration.

[0010] In the invention of claim 5, the control means (20) controls the operation of the advancing and retreating movement means (17) so that the cutting edge (16a) of the knife (16) appears and disappears from the sealing body (14) to cut the tubular packaging material (10), and is also characterized in that, when the packaging speed changes, the control means (20) controls the operation of the advancing and retreating movement means (17) so as to change the timing at which the knife (16) starts to protrude without changing the movement speed of the knife (16). According to the invention as defined in claim 5, even when the packaging speed is changed, the cutting action of the knife does not change, so that the tubular packaging material can be cut well. Effect of the Invention

[0011] According to the present invention, the knife timing (cutting timing) at which the tip of the knife protrudes most from the sealed body is automatically set in response to changes in the packaging speed, so that cut-off cutting of tubular packaging material can be performed well without the need for complicated adjustment work. [Brief description of the drawings]

[0012] [Figure 1] FIG. 2 is a schematic front view showing the seal cutting device. [Diagram 2] FIG. 2 is a schematic cross-sectional view of a main part of the seal cutting device. [Diagram 3] FIG. 2 is a schematic front view showing a cutting means disposed on the anvil. [Figure 4] FIG. 2 is a control block diagram of the seal cutting device. [Diagram 5] FIG. 13 is an explanatory diagram showing the screen of the display when the wrapping speed is changed. [Figure 6] FIG. 11 is an explanatory diagram showing the operation timing of the knife when the wrapping speed is changed. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Next, a preferred embodiment of the seal cutting device in a form fill and seal machine according to the present invention will be described below with reference to the attached drawings. In the embodiment, the seal cutting device will be described as being used as an end sealing device in a horizontal form fill and seal machine, but the form fill and seal machine may be a vertical form fill and seal machine or another type of form fill and seal machine. EXAMPLES

[0014] The horizontal form-fill-seal machine (packaging machine) is equipped with a seal cutting device that performs a center seal on a tubular film 10 formed by overlapping both longitudinal edge portions of a strip-shaped film (packaging material) pulled out from an original roll, clamps the tubular film 10 at the front and rear positions of articles 11 fed to the tubular film 10 at predetermined intervals, and performs end sealing and cutting in a direction intersecting the film conveyance direction (width direction). As shown in Fig. 2, a transport conveyor 12 and an output conveyor 13 are provided at the front and rear of the end sealing device in the film conveyance direction, which support the articles 11 from below via the tubular film 10 and convey them downstream, and the products (pillow packaged products) that have been end sealed, cut, and separated from the tubular film 10 on the upstream side are conveyed to the next process by the output conveyor 13.

[0015] 1 to 3, the end sealing device includes a pair of sealing bodies 14, 15 that rotate in opposite directions with respect to each other across the conveying path of tubular film 10, a knife 16 that is supported by one of the sealing bodies 14 and cuts tubular film 10, an advancing / retreating moving means 17 that moves knife 16 back and forth between a standby position (position where blade tip 16a is retracted into the sealing body) where blade tip 16a does not protrude from sealing surface 30b of one of the sealing bodies 14 and a maximum protruding position (protruding position) where blade tip 16a protrudes the most from sealing surface 30b, and a one-packaging size conveying means for conveying one package of tubular film 10. The end sealing device of the embodiment includes a sealer detection means 18 that detects the operating positions (rotational positions) of the pair of sealing bodies 14, 15 in the roll, a data input means 19 that sets the knife timing at which the knife 16 reaches the maximum protruding position by the advance / retract movement means 17 in response to the operating positions of the pair of sealing bodies 14, 15 detected by the sealer detection means 18, and a control means 20 that calculates the operation start timing (protrusion operation start timing) of the knife 16 from the standby position in one packaging cycle based on the knife timing set by the data input means 19 and the packaging speed of the packaging machine. The end sealing device of the embodiment is configured as an ultrasonic sealing mechanism in which one sealing body 14 disposed on one rotating shaft (first rotating shaft) 21 of a pair of rotating shafts 21, 22 that rotate in opposite directions with the conveyance path of the tubular film 10 in between is used as an anvil, and the other sealing body 15 disposed on the other rotating shaft (second rotating shaft) 22 is used as a horn that is ultrasonically vibrated by vibration generating means 23. In addition, each seal body 14, 15 in the embodiment has two seal pieces 30 or seal receiving pieces 27 described later provided at 180 degree intervals in the circumferential direction of the rotating shafts 21, 22, and in the embodiment, one packaging cycle is completed by 1 / 2 rotation of the rotating shafts 21, 22.

[0016] 1, the vibration generating means 23 is connected to the second rotating shaft 22, and the vibration generating means 23 includes a converter that generates ultrasonic waves and a booster that amplifies ultrasonic waves, and is configured to ultrasonically vibrate horn 15 at a predetermined amplitude, so that tubular film 10 transported by the film transport means or transport conveyor 12 is clamped at a predetermined pressure between anvil 14 and horn 15 to perform end sealing in the width direction by ultrasonic vibration. The pair of rotating shafts 21, 22 are rotatably supported by a pair of support members 24, 24 spaced apart in the width direction, and in this embodiment, horn 15 is disposed on the upper side between the pair of support members 24, 24, with the transport path in between, and anvil 14 is disposed on the lower side. In addition, the first rotating shaft 21 on which the anvil 14 is arranged has a shaft portion 21a extending from one widthwise end of the main body 28 of the anvil 14, which will be described later, connected to a sealing servo motor 25 as a driving means, and the shaft portion 21a and the second rotating shaft 22 of the horn 15 are connected via a transmission mechanism 26 such as a gear mechanism or a chain-sprocket mechanism, so that the anvil 14 and the horn 15 are driven to rotate in opposite directions by the driving of the sealing servo motor 25. In the rotation system of the sealing servo motor 25, a sealer detection means 18 capable of detecting the operating positions of the anvil 14 and horn 15 in one packaging cycle is provided, which is a combination of an encoder 49 attached to the sealing servo motor 25, a rotating plate 50 which rotates integrally with the first rotating shaft 21 of the anvil 14, and a sealer origin sensor 51 which detects the detectable portion formed on the rotating plate 50.The origin detection signal of the sealer origin sensor 51 (a signal which detects the detectable portion) and the number of pulses of the encoder 49 are input to the control means 20, and the origin position and current rotational position of the anvil 14 and horn 15 in one packaging cycle can be obtained.

[0017] 1 and 2, horn 15 is provided with a plurality of seal receiving pieces 27 (two at 180° intervals in this embodiment) that are spaced apart in the rotational direction and extend in the radial direction. Further, seal receiving piece 27 is formed with groove 27a that is recessed in the radial direction from the outer circumferential surface and extends in the width direction, and seal surfaces 27b, 27b are formed on both the front and rear sides in the rotational direction, sandwiching groove 27a, so as to extend linearly in the width direction.

[0018] 1 to 3, the anvil 14 includes a main body 28 that is disposed on the first rotary shaft 21 and rotates therewith, cutting means 29 having the knife 16 that is accommodated in an accommodation chamber 28a defined inside the main body 28 and that is movable in the radial direction, and seal pieces 30 that are disposed on the outer circumferential surface (outer surface) of the main body 28 corresponding to the movement direction of the cutting means 29 and pair with each seal receiving piece 27 of the horn 15. In the main body 28, through holes 28b that penetrate in the radial direction and through which the knives 16 of the cutting means 29 can pass are formed with a predetermined length in the width direction in correspondence with the locations where each seal piece 30 is disposed.

[0019] 2 and 3, a radially penetrating elongated hole 30a through which the knife 16 can pass is formed in the seal piece 30 of the anvil 14 at a position corresponding to the through hole 28b of the main body 28, and seal surfaces 30b, 30b that form a pair with the seal surfaces 27b, 27b of the horn 15 are formed to extend in the width direction on both the front and rear sides of the elongated hole 30a in the rotation direction of the anvil 14. The anvil 14 and the horn 15 rotate relative to the tubular film 10 being conveyed, and the tubular film 10 is clamped with a predetermined pressure by both seal surfaces 27b, 30b on both the front and rear sides of the clamping portion that holds the articles 11, which are supplied at predetermined intervals into the tubular film 10, and ultrasonic vibrations generated by the horn 15 are transmitted to the clamping portion to melt the heat-sealed film, and an end seal portion that intersects with the conveyance direction of the tubular film 10 is formed.

[0020] As shown in Figures 2 and 3, the cutting means 29 comprises a movable member 31 supported within the storage chamber 28a of the anvil 14 and capable of moving back and forth radially, and a knife 16 arranged at a position on the movable member 31 corresponding to each seal piece 30, and the cutting means 29 is configured such that, as the movable member 31 moves back and forth, the blade tip 16a of the knife 16 passes through the corresponding through hole 28b and long hole 30a and protrudes from the seal surface 30b to cut the tubular film 10.

[0021] The cutting means 29 is connected to the advancing and retreating means 17 which moves the cutting means 29 forward and backward in the radial direction. As shown in Figs. 1 and 3, the advancing and retreating means 17 includes a link mechanism 33 supported in the accommodation chamber 28a and connected to the moving member 31, an operating mechanism 34 which operates the link mechanism 33, and a knife driving servo motor 35 as a driving means which operates the operating mechanism 34. The shaft portion 21b of the first rotating shaft 21 opposite to the shaft portion 21a to which the transmission mechanism 26 of the main body 28 is connected is configured as a hollow shaft, and an operating rod 36 which constitutes the operating mechanism 34 is inserted and supported in the shaft portion 21b so as to be axially movable. One end of the operating rod 36 is connected to the link mechanism 33, and the other end is connected to a movable body 37 which is movable along the axial direction. Further, an output shaft 35a of the knife drive servomotor 35 extends in a direction intersecting with the operating rod 36, and an end of a lever 38 rotatably disposed on the output shaft 35a via an eccentric ring is rotatably disposed on the movable body 37. The link mechanism 33 connected to the operating rod 36 positions the movable member 31 at an intermediate position in the forward / rearward movement direction at a position where none of the blade edges 16a of both knives 16, 16 protrudes from the seal surfaces 30b, 30b of the anvil 14. When the blade edge 16a of one knife 16 protrudes from the corresponding seal surface 30b, the blade edge 16a of the other knife 16 does not protrude from the corresponding seal surface 30b and retracts from the elongated hole 30a of the seal piece 30 into the through hole 28b.

[0022] The advancing / retreating moving means 17 is configured to move the moving member 31 in conjunction with the rotation of the rotating shafts 21, 22 of the anvil 14 and the horn 15, so that the cutting edge 16a of the knife 16 protrudes from the sealing surface 30b of the anvil 14 at the timing when the sealing surface 30b of the anvil 14 and the sealing surface 27b of the horn 15 reach a position where they clamp the tubular film 10. 2, the sealing timing when one set of seal piece 30 and seal receiving piece 27 of anvil 14 and horn 15 are positioned at a clamping position where they mutually clamp tubular film 10, and the two seal pieces 30 and seal receiving pieces 27 of anvil 14 and horn 15 are aligned vertically, is 180 degrees when one packaging cycle is converted into an angle of 360 degrees, and the timing when anvil 14 and horn 15 rotate 90 degrees in the rotation direction from the clamping position and assume a horizontal, lateral position is set as the origin (0 degrees, origin position). In other words, it is specified that one packaging cycle corresponds to every half rotation of anvil 14 and horn 15.

[0023] As shown in FIG. 1, a knife detection means 39 capable of detecting the operating position (position of the blade tip 16a) of the knife 16 in one packaging cycle is disposed in the rotation system of the knife drive servomotor 35. The knife detection means 39 includes an encoder 40 attached to the knife drive servomotor 35, a rotating plate 41 disposed to rotate integrally with the output shaft 35a of the knife drive servomotor 35, and a knife origin sensor 42 for detecting a detection target portion 41a formed on the rotating plate 41, and an origin detection signal of the knife origin sensor 42 and the number of pulses of the encoder 40 are input to the control means 20. In the embodiment, an origin position signal of the two knives 16 is output when the rotating plate 41 detects two detection targets 41a spaced apart in the circumferential direction. In such an origin position, both knives 16 are set to a position where the blade tips 16a do not protrude beyond both sealing surfaces 30b, 27b of the anvil 14 and the horn 15.

[0024] 4, the sealing servomotor 25 and the knife driving servomotor 35 are controllably connected to the control means 20, and various detection means including the encoders 49, 40 attached to the servomotors 25, 35, the knife origin sensor 42 of the knife detection means 39, and the sealer origin sensor 51 of the sealer detection means 18 are also connected to the control means 20. The control means 20 is also connected to a touch panel 19 as the data input means, which allows data to be set by data input or item selection and can display set data values ​​and various setting information related to the operation of the packaging machine, and the touch panel 19 allows input of various control data for driving and controlling the horizontal bag form-fill-seal machine, as well as predetermined data values ​​related to the packaging speed, the film length (cut pitch) corresponding to one package length, and size data of the articles 11. The control means 20 can obtain predetermined calculation results by a calculation unit 44 based on various data input and set by the touch panel 19.

[0025] Based on the data value related to the knife timing of knife 16 input and set via touch panel 19 and the wrapping speed, calculation unit 44 of control means 20 calculates the operation start timing of knife 16 corresponding to the wrapping speed for the knife timing so that cutting edge 16a of knife 16 reaches the maximum protrusion position in one wrapping cycle in accordance with the time when tubular film 10 is clamped by anvil 14 and horn 15. Even when the wrapping speed is changed, the operation start timing of knife 16 corresponding to the operation timing of anvil 14 and horn 15 is calculated in accordance with the time when tubular film 10 is clamped by anvil 14 and horn 15. Then, based on the result calculated by calculation unit 44, control means 20 controls knife drive servo motor 35 so as to be synchronized with sealing servo motor 25 that drives anvil 14 and horn 15, and knife 16 is operation-controlled so that knife 16 moves to the maximum protrusion position and retreats from the maximum protrusion position while maintaining the movement speed (operation speed) of knife 16 at a predetermined common speed that is not dependent on changes in the wrapping speed. In this manner, the movement speed of the knife 16 is set as a common speed that is operated at a high speed to provide instantaneous operation that is common to all wrapping speeds without changing the push-out and return speeds, including acceleration and deceleration, and that can effectively cut the tubular film 10.

[0026] A setting screen 45 is prepared on the touch panel 19 for inputting and setting the knife timing of the knife 16. As shown in FIG. 5, the setting screen 45 displays a setting value input screen for the knife timing in a setting value input area arranged to the right of the selection area by selecting a setting item name "knife operation" 46 displayed in a setting item selection area on the left side of the screen. In the data setting input screen 45, a data input item name "end timing of knife extension arrival" is displayed as a knife timing setting section 47, and a "setting value input display section" for inputting the operation positions (operation timing) of the anvil 14 and the horn 15 for one wrapping cycle when the blade tip 16a of the knife 16 reaches the maximum protruding position is displayed in a position next to the item name. In the illustrated example, the knife timing is set to 180 degrees as described above. In addition, an operation start timing display section 48 is provided on the right side of the knife timing setting section 47, in which an item name "knife extension start timing" indicating the operation start timing of the knife 16 and a numerical display section displaying the calculated value of the operation start timing are arranged vertically. By inputting and setting the set value of the knife timing, the "knife extension start timing" at the operating positions (operation timing) of the anvil 14 and horn 15 for one wrapping cycle is automatically calculated by the calculation unit 44, and the timing value is displayed on the numerical display unit. Note that, for data input setting of the knife timing, by touching the "set value input display unit" of the knife timing setting unit 47, a numerical input key is displayed as a pop-up window, and the knife timing can be input as data using the numerical input key.

[0027] Next, the operation of the end seal device according to the embodiment will be described. When operating the packaging machine, a setting screen 45 is displayed on the touch panel 19, and the numeric display section of a knife timing setting section 47 is touched to operate the displayed numeric input keys to input the knife timing at which the cutting edge 16a of the knife 16 protrudes most from the sealing surface 30b of the anvil 14 as a numerical value based on the operation timing of the anvil 14 and the horn 15. The calculation section 44 calculates the operation start timing of the knife 16 based on the inputted and set numeric value of the knife timing and the packaging speed, and the calculated value is displayed on the numeric display section of the operation start timing display section 48. For example, as shown in FIG. 6(1), when the first packaging speed during operation is set to 200 pcs / min, if a numerical value (180 degrees) is input and set as the knife timing at which the cutting edge 16a of the knife 16 protrudes most from the sealing surface 30b of the anvil 14, converted into an angle of 360 degrees for one packaging cycle, the numerical value (160 degrees) of the operation start timing of the knife 16 is calculated by the calculation unit 44 and displayed on the numerical display portion of the operation start timing display unit 48. Then, in relation to the operating positions of the anvil 14 and horn 15, which rotate at the packaging speed, based on the signal from the encoder 49, the control means 20 controls the drive of the knife drive servo motor 35 so that the knife 16 (cutting means 29) begins operation at the calculated operation start timing (160 degrees) and reaches the maximum protruding position at the input-set knife timing (180 degrees), and the knife 16 cuts through the tubular film 10 at a predetermined protruding speed, and the tubular film 10 is clamped between the sealing surfaces 30b, 27b of the anvil 14 and horn 15 located on either side of the knife 16, thereby end sealing and cutting the tubular film 10.

[0028] In contrast to this, for example, when the packaging speed during operation is changed to a second packaging speed of 100 pcs / min, which is slower than the first packaging speed, the protrusion and return speeds of the knife 16 are the same as those in the case of the first packaging speed, so that, as shown in FIG. 6(2), the knife timing value (180 degrees) at which the cutting edge 16a protrudes furthest from the sealing surface 30b of the anvil 14 remains unchanged, and the calculation unit 44 calculates the knife timing at which the knife 16 starts to operate to a value (170 degrees) that is later than the knife timing at which the knife 16 starts to operate at the first packaging speed. 6(3), even when the packaging machine is operated at a third packaging speed of 20 pcs / min, which is a preset, low, adjusted operating speed, by continuously pressing an inching button of the packaging machine, the protruding and returning speeds of the knife 16 are operated at a predetermined common speed that is not dependent on changes in the packaging speed, and the knife timing value (180 degrees) at which the blade tip 16a protrudes most from the sealing surface 30b of the anvil 14 is not changed, and the calculation unit 44 calculates an operation start timing of the knife 16 that is further delayed (175 degrees) than the knife timing at which the knife 16 starts operating when the packaging speed is 100 pcs / min. In other words, when the packaging speed is changed, the operation start timing of the knife 16 is changed without changing the moving speed of the knife 16. Control means 20 then drives and controls knife drive servo motor 35 so that movement of knife 16 begins at each calculated knife timing (170 degrees, 175 degrees) in relationship to the operating positions of anvil 14 and horn 15, which rotate at each wrapping speed, based on the signal from encoder 49, and reaches the maximum protruding position at the input set knife timing (180 degrees). As a result, knife 16 reaches the maximum protruding position corresponding to the timing at which anvil 14 and horn 15 reach the meshing position (position where tubular film 10 is clamped), and tubular film 10 clamped between sealing surfaces 30b, 27b of anvil 14 and horn 15 is cut.

[0029] In the end sealing device of the embodiment, the operation start timing of the knife 16 according to the wrapping speed is automatically calculated by the calculation unit 44 by simply inputting the knife timing at which the knife 16 is at the maximum protruding position, so that when the wrapping speed is changed, the operation start timing can be cut at the same location in relation to the clamping position of the tubular film 10 by the anvil 14 and the horn 15 without manually adjusting the operation start timing each time. In addition, the operation start timing of the knife 16 is changed without changing the moving speed (acceleration and deceleration) of the knife 16 due to a change in the wrapping speed, so that the cutting action of the knife 16 does not change and the tubular film 10 can be cut well, preventing the occurrence of defective cut products. For example, even if the wrapping speed is extremely lower than the standard wrapping speed of the packaging machine (e.g., 200 pieces / min), such as during inching operation, the cutting of the tubular film 10 by the knife 16 does not change and the tubular film 10 can be cut well.

[0030] In the end sealing device of the embodiment, the advance / retract movement means 17 of the cutting means 29 is configured to be operated by the knife drive servo motor 35, so that the knife 16 can be advanced and retracted with precision. This prevents the knife 16 from coming into contact with the sealing surface 27b of the horn 15, etc., and being damaged due to a timing discrepancy between the advance / retract movement of the knife 16 and the rotational movement of the anvil 14 and the horn 15. In other words, even in high-speed packaging, the knife operation does not delay in conjunction with the rotation of the sealing bodies 14 and 15, and the tubular film 10 can be cut with precision. In addition, the knife timing is configured to be inputted numerically on the setting screen 45 displayed on the touch panel 19, so that the knife timing can be easily set.

[0031] In the end sealing device of the embodiment, the pair of sealing bodies 14, 15 are of a rotating type, and therefore can be suitably used for packaging requiring high speed. Also, the sealing bodies 14, 15 are configured to end seal the tubular film 10 by ultrasonic vibration, and the horn 15, which is not provided with the cutting means 29, is configured to be ultrasonically vibrated by the vibration generating means 23. Therefore, the cutting means 29 and the advancing / retreating means 17 are not directly affected by the ultrasonic vibrations from the vibration generating means 23, and it is possible to prevent a situation in which the cutting means 29 and the advancing / retreating means 17 are worn out by the ultrasonic vibrations, causing malfunctions and changing the knife timing.

[0032] (Example of change) The present invention is not limited to the configurations of the examples, and can be modified as follows, for example. Furthermore, the configurations described in the examples can be modified in various ways within the scope of the present invention, without being limited to the following modifications. (1) The number of seal pieces 30 provided on the anvil 14 is not limited to two and may be one, and the number of seal receiving pieces 27 provided on the knives 16 and horns 15 arranged on the movable member 31 may correspond to the number of seal pieces 30 provided on the anvil 14. (2) Although the advancing / retreating means 17 for advancing and retracting the knife 16 is constituted by the link mechanism 33, the actuating mechanism 34, and the knife drive servomotor 35, various other actuation modes may be adopted for the advancing / retreating means 17. For example, a configuration in which the link mechanism 33 is actuated by an air cylinder instead of the servomotor 35, or a configuration in which the knife 16 is moved forward and backward by a drive means such as a servomotor or an air cylinder by another actuating mechanism without using a link mechanism may be adopted. (3) In the embodiment, the present invention is applied to a rotary end seal device in which a pair of seal bodies 14, 15 are rotationally driven. However, the present invention is not limited to the rotary type, and can be applied to a cut-off knife type of a seal cutting device in an opening / closing type or other box motion type. (4) The seal cutting device has been exemplified as being applied to an ultrasonic end seal device, but it can also be applied to a seal cutting device of a heat seal type that uses a heated seal body. (5) The knife timing at which the cutting edge 16a of the knife 16 reaches the maximum protruding position is directly input as a numerical value via the touch panel 19. However, it is also possible to adopt a setting form in which numerical data is called up and set, or in which the sealing bodies 14, 15 are moved to the engaging position, the timing data is read and displayed, and the set data is set as the knife timing at which the cutting edge 16a of the knife 16 reaches the maximum protruding position. Alternatively, the knife timing at which the cutting edge 16a of the knife 16 reaches the maximum protruding position may be stored in advance as a programmed setting value in relation to the engagement timing at which the sealing bodies 14, 15 reach their engagement positions, regardless of the input setting, and the knife timing at which the maximum protruding position is reached may be corrected relative to the programmed setting value to set the knife timing. [Explanation of symbols]

[0033] 10 Cylindrical film (cylindrical packaging material), 14 Anvil (one sealing body) 15 horn (seal body), 16 knife, 16a cutting edge, 17 forward / backward moving means 18 sealer detection means, 19 touch panel (data input means), 20 control means 21b shaft portion (hollow shaft), 25 seal servo motor, 33 link mechanism 35 Knife driving servo motor, 36 Operating rod, 39 Knife detection means

Claims

1. A seal cutting device for a bag making and filling machine, which clamps a tubular packaging material with a pair of sealing bodies facing each other across a conveying path of the tubular packaging material, seals the tubular packaging material in a direction intersecting the conveying direction, and cuts the tubular packaging material by protruding a knife tip from one of the sealing bodies, a forward / backward movement means for moving the knife at a predetermined speed so that the cutting edge of the knife appears and disappears from the sealing body to cut the tubular packaging material; a sealer detection means for detecting an operating position of the seal body, a knife timing at which the blade tip protrudes most from the sealing body at a timing when the sealing body clamps the cylindrical packaging material; A control means is provided for calculating the timing at which the knife should start to protrude in accordance with the wrapping speed and controlling the operation of the forward / backward moving means so as to achieve the set knife timing. A seal cutting device for a bag making and filling machine.

2. a knife driving servomotor for driving the forward and backward moving means; and a knife detection means for detecting a movement position of the knife.

2. The seal cutting device in a bag making and filling machine according to claim 1, wherein the knife timing at which the blade tip is at its most protruding position in relation to the operating position of the sealing body detected by the sealer detection means is inputted numerically by a data input means.

3. a sealing servomotor that rotates the pair of sealing bodies; 3. The seal cutting device for a bag making and filling machine according to claim 2, wherein the advancing and retreating moving means is connected to the knife, the blade tip of which is housed and supported in the one of the sealing bodies so as to be capable of retracting therefrom.

4. One of the sealing bodies is an anvil that houses and supports the knife, and the other sealing body is an ultrasonic sealing mechanism that is an ultrasonically vibrating horn, The forward and backward moving means is a link mechanism that allows the tip of the knife to be extended and retracted from the anvil; an actuating rod that is axially movably inserted into the hollow shaft of the anvil and has one end connected to the link mechanism; a servo motor for driving the knife, which moves the actuating rod in the axial direction; 4. The seal cutting device in a bag making and filling machine as described in claim 3, wherein the knife detection means is arranged so as to be capable of detecting the position of the tip of the knife moved by the knife drive servo motor, and the sealer detection means is arranged so as to be capable of detecting the rotational position of the seal body caused by the sealing servo motor.

5. The seal cutting device in a bag making and filling machine described in any one of claims 1 to 4, characterized in that the control means controls the operation of the advancing and retreating moving means so that the tip of the knife emerges and retracts from the sealing body to cut the tubular packaging material, and when the packaging speed changes, controls the operation of the advancing and retreating moving means so that the timing at which the knife starts to protrude is changed without changing the knife movement speed.

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