Bag making and packaging machine

Abstract

To improve sealing failure in sealing by ultrasonic vibration.SOLUTION: An ultrasonic sealing device that performs ultrasonic sealing on the packaging material conveyed by the packaging material feeding device along the conveying direction by ultrasonic vibration, and a conveyance control unit that controls the conveyance by the packaging material feeding device, wherein the ultrasonic sealing device starts the ultrasonic vibration simultaneously with or after the start of the conveyance of the packaging material by the packaging material feeding device, and the conveyance control unit sets the conveying speed in a certain period from the start of the conveyance by the packaging material feeding device to a low speed that is lower than an operating speed that is a conveying speed set during a packaging operation.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a bag-making and packaging machine. [Background technology]

[0002] Conventionally, a technology for ultrasonic sealing using ultrasonic vibrations in a form-fill-seal machine equipped with an ultrasonic horn and an anvil has been known. In ultrasonic sealing using ultrasonic vibrations, the ultrasonic vibrations stop when the conveyance of the packaging material is stopped (standby state) and resume when the conveyance resumes. However, since it takes time for the ultrasonic vibrations in the ultrasonic horn to stabilize after the ultrasonic vibrations start, during this time, the area of ​​the packaging material that has passed through the ultrasonic sealing device may not be properly sealed, resulting in poor sealing. In response to this, Patent Document 1 discloses a technology in a form-fill-seal machine that applies ultrasonic vibrations to a film in a time region immediately before transitioning to a first time point at which the film conveyance starts, and applies ultrasonic vibrations having an amplitude corresponding to the film's speed to the film in a time region after transitioning to the first time point. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-236622 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the technology of Patent Document 1, ultrasonic vibrations continue to be applied to the film when film transport is stopped, which has the problem of potentially causing poor sealing, such as the sealing area becoming dirty in that area.

[0005] The present invention has been made in consideration of the above points, and has as its object to improve sealing defects caused by ultrasonic vibration. [Means for solving the problem]

[0006] The bag-making and packaging machine of the present invention comprises a packaging material feeding device that conveys packaging material along a conveying direction, an ultrasonic sealing device that applies ultrasonic vibrations to the packaging material conveyed by the packaging material feeding device along the conveying direction to form a seal, and a conveying control unit that controls the conveying by the packaging material feeding device, wherein the ultrasonic sealing device starts the ultrasonic vibrations simultaneously with or after the packaging material feeding device starts conveying the packaging material, and the conveying control unit sets the conveying speed for a certain period of time from the start of conveying by the packaging material feeding device to a low speed that is slower than the operating speed, which is the conveying speed set during packaging operation.

[0007] Another aspect of the present invention is a bag-making packaging machine comprising: a packaging material feeding device that conveys packaging material along a conveying direction; an ultrasonic sealing device that ultrasonically seals the packaging material conveyed by the packaging material feeding device using ultrasonic vibrations; and a conveying control unit that controls conveying by the packaging material feeding device, wherein the ultrasonic sealing device starts the ultrasonic vibrations simultaneously with or after the packaging material feeding device starts conveying the packaging material, and the conveying control unit controls the conveying speed of the packaging material to increase to a set operating speed over a time period equal to or longer than the rise time required for the amplitude of the ultrasonic vibrations to reach a set operating amplitude from the timing of the start of the ultrasonic vibrations, and the ultrasonic sealing device generates the ultrasonic vibrations at an amplitude corresponding to the conveying speed. [Effects of the Invention]

[0008] According to the bag-making and packaging machine of the present invention, it is possible to improve sealing defects caused by ultrasonic vibrations. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a perspective view showing the overall configuration of a bag-making packaging machine. [Figure 2] FIG. 2 is a front view showing a former, a filling cylinder, and an ultrasonic vertical sealing device. [Figure 3] FIG. 2 is a configuration diagram of a control unit. [Figure 4] 10A and 10B are explanatory diagrams of ultrasonic vertical sealing and timing of conveyance of packaging material. [Figure 5] 10 is a flowchart showing processing by a control unit. [Figure 6] FIG. 10 is an explanatory diagram of a first modified example. [Figure 7] FIG. 10 is an explanatory diagram of a second modified example. [Figure 8] FIG. 10 is an explanatory diagram of a fourth modified example. DETAILED DESCRIPTION OF THE INVENTION

[0010] FIG. 1 is a perspective view showing the overall configuration of a form-fill-seal machine 1. FIG. 2 is a front view showing a former, a filling tube, and an ultrasonic vertical sealing device used in the form-fill-seal machine 1 shown in FIG. 1. In this embodiment, the form-fill-seal machine 1 is a vertical form-fill-seal machine in which the filling tube is installed so that its longitudinal direction is parallel to the direction of gravity, the product to be packaged (the material to be packaged) is fed through the filling tube, and bags are made from the packaging material while the material to be packaged is filled into the bags, producing a bag package. Furthermore, the form-fill-seal machine 1 of this embodiment is a so-called continuous machine in which, when operation is started, the conveyance of the packaging material begins and the packaging material is then conveyed continuously. Note that the form-fill-seal machine 1 of this embodiment may be a horizontal packaging machine instead of a vertical packaging machine.

[0011] In the following, the direction in which the packaging material is conveyed during the process of manufacturing the bag package will be referred to as the conveying direction, and the direction opposite to the conveying direction will be referred to as the reverse conveying direction. Also, in the conveying path of the packaging material, the direction ahead in the conveying direction will be referred to as the front, and the side opposite to the front will be referred to as the rear.

[0012] The form-fill-seal machine 1 shown in FIG. 1 includes a payout mechanism 10 that pays out a strip of packaging material Fw from a take-up roll Fr on which the material is wound, stores a portion of the material, and applies an appropriate tension to the material; and an accessory device 20, such as a printer, that prints on the strip of packaging material Fw. The form-fill-seal machine 1 also includes a former 30 that bends the continuously paid-out strip of packaging material Fw into a substantially tubular packaging material. The form-fill-seal machine 1 further includes an ultrasonic vertical sealing device 60 that applies ultrasonic vertical sealing to the bent substantially tubular packaging material to form a tubular packaging material Ft, and a horizontal sealing device 40 that applies a transverse seal to the tubular packaging material Ft formed by the ultrasonic vertical sealing. The form-fill-seal machine 1 also includes a filling tube 50 that is inserted into the former 30 and into which the packaging material is inserted; and a suction-type packaging material feed device 70 that feeds the tubular packaging material Ft. Furthermore, an encoder 90 for measuring the transport speed of the packaging material is provided above the packaging material feed device 70.

[0013] As shown in FIG. 1, the packaging material feed device 70 is a suction paper feed device that feeds the tubular packaging material Ft in a conveying direction while sucking the tubular packaging material Ft from the outside. Specifically, the packaging material feed device 70 includes two paper feed belts 71a, 71b arranged facing each other on both diametrical sides of the tubular packaging material Ft. Each paper feed belt 71a, 71b has a plurality of suction holes 72 arranged in a longitudinal row at the center of its width. Each paper feed belt 71a, 71b is wound around a motor-driven drive pulley 73, a driven pulley 74, and a guide pulley 75. A suction device (not shown) sucks air through the suction holes 72. The driving force from the drive pulley 73 sucks the tubular packaging material Ft in contact with the paper feed belts 71a, 71b from the outside, and conveys the tubular packaging material Ft downward along the direction of gravity. As the conveyed tubular packaging material Ft moves relative to the ultrasonic vertical sealing device 60, the edge portions Fea and Feb on both sides of the tubular packaging material Ft are continuously sealed as ultrasonic vertical seals Sc.

[0014] As shown in FIG. 2 , the former 30 includes a collar 31 that bends the packaging strip Fw into a generally cylindrical shape, and a tubular portion 32 that is connected to the collar 31 and through which the bent packaging strip Fw passes. The collar 31 includes a curved collar body 33 that acts on the packaging strip Fw to bend it into a generally cylindrical shape, and an overlapping portion 34. The overlapping portion 34 is formed on opposing leading edge portions 34a, 34b of the collar body 33. The opposite edge portions Fea, Feb of the packaging strip Fw overlap as it passes through the overlapping portion 34. The collar body 33 wraps around the tubular portion 32 from the back side to the front side in a smoothly curved shape, and the overlapping portion 34 is formed at the lower end of the front of the collar body 33.

[0015] The cylindrical portion 32 includes a cylindrical main body 35 that extends in a cylindrical form below the overlapping portion 34 of the collar portion 31 and terminates at a lower end 36. The cylindrical main body 35 is formed with a slit 37 that connects to the overlapping portion 34 and extends vertically, and through which the overlapping edge portions Fea and Feb can pass when they protrude to the front side.

[0016] The filling tube 50 fitted inside the former 30 is a cylindrical body made of metal (stainless steel). The filling tube 50 is fitted inside the tubular portion 32 of the former 30 with a gap 51 therebetween, and the strip-shaped packaging material Fw can pass through the gap 51 between the inner peripheral surface of the tubular portion 32 and the outer peripheral surface of the filling tube 50. In the example shown in FIG. 2, the filling tube 50 extends further downward from the lower end 36 of the tubular portion 32 of the former 30.

[0017] The ultrasonic vertical sealing device 60 is disposed directly below the overlapping portion 34 of the former 30. The ultrasonic vertical sealing device 60 according to this embodiment is an ultrasonic device equipped with an ultrasonic horn 61, an ultrasonic generator 62, and an anvil 64. The ultrasonic horn 61, the ultrasonic generator 62, and the anvil 64 are unitized as an ultrasonic vertical sealing unit. The strip-shaped packaging material Fw is conveyed from the former 30 to the ultrasonic vertical sealing device 60 with its edge portions Fea and Feb sandwiched in the slit 37. The ultrasonic vertical sealing device 60 melts and welds the edge portions Fea and Feb of the strip-shaped packaging material Fw by applying pressure and vibrating them. In this manner, ultrasonic vertical seals Sc are applied to the strip-shaped packaging material Fw by the ultrasonic vibrations, forming a tubular packaging material Ft. Note that hereinafter, the process of applying ultrasonic vertical seals Sc to the strip-shaped packaging material Fw by the ultrasonic vertical sealing device 60 is referred to as the ultrasonic vertical sealing process. Here, the ultrasonic vertical sealing device 60 is an example of an ultrasonic sealing device that performs sealing by ultrasonic vibration.

[0018] The ultrasonic horn 61 and the anvil 64 are made of metal and are disk-shaped, with their sides facing each other. The edges Fea and Feb of the strip-shaped packaging material Fw are sandwiched between the ultrasonic horn 61 and the anvil 64. The ultrasonic generator 62 is provided on the side of the disk of the ultrasonic horn 61 opposite the side facing the strip-shaped packaging material Fw. In the ultrasonic generator 62, a converter consisting of a piezoelectric element converts high-frequency electrical energy into mechanical vibration energy, which is then amplified by a booster. Ultrasonic vibrations are then transmitted to the anvil 64 through a resonator called the ultrasonic horn 61. The edges Fea and Feb, which are sandwiched between the ultrasonic horn 61 and the anvil 64 under pressure, are melted and welded by frictional heat generated by rubbing the edges together at the interface between them due to the vibration energy transmitted to the ultrasonic horn 61. Note that, although a roller-type device is used as the ultrasonic vertical sealing device 60 according to this embodiment, this is not limited thereto; a block-type device may also be used.

[0019] As shown in Figure 1, the horizontal sealing device 40 has two horizontal heat seal bars 41a, 41b arranged opposite each other. The tubular packaging material Ft is sealed in the horizontal direction (horizontal seal Se) by pressurizing and heating it between the horizontal heat seal bars 41a, 41b, sealing the top opening of the previously formed bag P1 and forming the bottom of the following bag P2. A cutter device 45 is incorporated into the horizontal sealing device 40. As the cutter device 45, a cutter blade 46 is incorporated into one of the horizontal heat seal bars 41 so that it can move forward and backward, and the other horizontal heat seal bar 41 is formed with a groove 47 into which the advanced cutter blade 46 fits to cut the sandwiched tubular packaging material Ft.

[0020] A weighing machine 100 for the packaging materials is installed above the bag-making and packaging machine 1. The weighing machine 100 weighs the packaging materials to be filled into one bag and supplies the weighed packaging materials into the filling tube 50 of the bag-making and packaging machine 1. The supplied packaging materials pass through the filling tube 50, enter the bag, and are sealed with ultrasonic vertical seals Sc and horizontal seals Se.

[0021] 3 is a functional configuration diagram of the control unit 80 that controls the operation of the bag making and packaging machine 1. The control unit 80 includes a processor such as a CPU and a storage unit such as a ROM and RAM, and executes various programs stored in the storage unit. The control unit 80 has a functional configuration including a conveyance control unit 81 and an ultrasonic wave control unit 82. The functions of the conveyance control unit 81 and the ultrasonic wave control unit 82 are realized by the processor reading and executing programs stored in the storage unit. In other words, the processes described as being executed by the conveyance control unit 81 and the ultrasonic wave control unit 82 are actually processes executed by the control unit 80.

[0022] The conveyance control unit 81 instructs the packaging material feeding device 70 to start and stop conveyance. Furthermore, the conveyance control unit 81 controls the conveyance speed. The ultrasonic control unit 82 instructs the ultrasonic vertical sealing device 60, which is an ultrasonic vertical sealing device, to start and stop ultrasonic vibration.

[0023] FIG. 4 is an explanatory diagram of the relationship between the amplitude of ultrasonic vibrations (ultrasonic amplitude) by the ultrasonic vertical sealing device 60 and the conveying speed by the packaging material feeding device 70. FIG. 4(a) is a graph showing the ultrasonic amplitude by the ultrasonic vertical sealing device 60. The horizontal axis of the graph represents time, and the vertical axis represents ultrasonic amplitude. FIG. 4(b) is a graph showing the conveying speed of packaging material in a conventional packaging machine. The horizontal axis of the graph represents time, and the vertical axis represents conveying speed. FIG. 4(c) is a graph showing the conveying speed of packaging material in the form-fill-seal machine 1 according to the present embodiment. The horizontal axis of the graph represents time, and the vertical axis represents conveying speed.

[0024] t1 is the timing at which an instruction to start operation of the bag-making packaging machine 1 is issued (hereinafter referred to as the start instruction timing). As shown in Figure 4(a), a certain amount of time passes from when ultrasonic vibration starts at start instruction timing t1 until timing t2 at which the set ultrasonic amplitude is reached. Here, the set ultrasonic amplitude is a value set as the ultrasonic amplitude during packaging operation in the bag-making packaging machine 1, and hereinafter this will be referred to as the operating amplitude.

[0025] 4(b), it also takes a certain amount of time for the packaging material feeding device 70 to reach the set conveying speed after the start of the conveying operation at start instruction timing t1. Here, the set conveying speed is a value set as the conveying speed during packaging operation in the bag-making packaging machine 1, and will be referred to as the operating speed hereinafter. Here, timing t2 at which the ultrasonic amplitude reaches the operating amplitude is later than timing t3 at which the conveying speed reaches the operating speed. This may result in poor sealing in the ultrasonic vertical seal Sc created by ultrasonic vibration.

[0026] There is an optimal relationship between ultrasonic amplitude and conveying speed for stable ultrasonic vertical sealing. The larger the ultrasonic amplitude, the faster the conveying speed. The operating speed and operating amplitude are set according to this relationship. However, if the operating speed is reached before the operating amplitude is reached, the ultrasonic amplitude will be too small compared to the conveying speed, making it impossible to achieve stable ultrasonic vertical sealing and resulting in poor sealing.

[0027] In contrast, in this embodiment, the conveying control unit 81 controls the conveying speed so that it is kept constant at a speed slower than the operating speed for a certain period from the start instruction timing t1, and then controls the conveying speed to the operating speed after the certain period has elapsed. Here, the speed slower than the operating speed is a preset value, and hereinafter this speed will be referred to as the low speed.

[0028] As shown in FIG. 4(c), the conveyance control unit 81 sets the conveyance speed to a low speed slower than the operating speed at start instruction timing t1. As a result, the packaging material is conveyed at a low speed. Furthermore, the conveyance control unit 81 changes the setting of the conveyance speed at timing t4, which is before timing t2, so that the conveyance speed becomes the operating speed at timing t2. As a result, from timing t4 onwards, the conveyance control unit 81 controls the packaging material feeding device 70 so that conveyance is carried out at the operating speed. However, it takes time for the actual conveyance speed to reach the operating speed after the conveyance speed is set to the operating speed, and this period corresponds to the period from timing t4 to timing t2.

[0029] Thus, in the bag making and packaging machine 1 according to this embodiment, the amplitude of the ultrasonic vibrations has not yet reached the operating amplitude immediately after the start command timing t1, but during this time the packaging material is conveyed at a low speed. This allows for more stable ultrasonic vertical sealing than when conveyance is started with the conveying speed set to the operating speed.

[0030] 5 is a flowchart showing the processing by the control unit 80. The control unit 80 waits until an operation start instruction is input in response to a user operation or the like (N in step S100). Here, the operation start instruction is information that instructs the bag making packaging machine 1 to start a bag making operation. When the operation start instruction is input (Y in step S100), the control unit 80 proceeds to step S102.

[0031] Then, the ultrasonic control unit 82 starts ultrasonic vibration, and further, the conveyance control unit 81 starts conveying the packaging material (step S102). Specifically, the ultrasonic control unit 82 instructs the ultrasonic vertical sealing device 60 to start ultrasonic vibration and sets the ultrasonic amplitude value to the operating amplitude. Furthermore, the conveyance control unit 81 starts conveying the packaging material. Specifically, the conveyance control unit 81 instructs the packaging material feeding device 70 to start conveying and sets the conveyance speed value to a low speed. As a result, ultrasonic vibration by the ultrasonic vertical sealing device starts, and further, conveyance of the packaging material by the packaging material feeding device 70 starts. The conveyance speed of the packaging material becomes a constant value at a low speed that is slower than the operating speed, as shown in FIG. 4(c). It is assumed that the ultrasonic vibration and conveyance of the packaging material are controlled to start simultaneously.

[0032] Next, the transfer control unit 81 checks whether a certain period of time has elapsed since the operation start command was input (step S104). Here, the certain period of time is a period shorter than the period from the start command timing t1 to the timing t2 at which the ultrasonic amplitude reaches the operating amplitude, and this period is assumed to be set in advance. In FIG. 4(c), the certain period corresponds to the period from timing t1 to t4.

[0033] If the predetermined time has not elapsed (N in step S104), the conveyance control unit 81 continues conveyance at the low speed. On the other hand, if the predetermined time has elapsed (Y in step S104), the conveyance control unit 81 changes the conveyance speed from the low speed to the operating speed (step S106). As a result, as shown in FIG. 4(c), the conveyance speed begins to increase after timing t4. In the example of FIG. 4(c), the conveyance speed is controlled so that it reaches the operating speed at timing t2, when the ultrasonic amplitude reaches the operating amplitude. In this manner, it is preferable that the conveyance speed gradually increase so that it reaches the operating speed at timing t2. However, as another example, the timing at which the conveyance speed reaches the operating speed does not have to coincide with timing t2. In this case, the degree of deviation from the relationship between the operating amplitude and the operating speed required for stable ultrasonic vertical sealing is small, so that appropriate ultrasonic vertical sealing is performed.

[0034] As another example, after timing t4, the conveyance control unit 81 may control the conveyance speed to increase to the operating speed to an extent that the ultrasonic amplitude can keep up, and the ultrasonic control unit 82 may control the ultrasonic vertical sealing device 60 to generate ultrasonic vibrations with an ultrasonic amplitude according to the conveyance speed, which is determined from the correspondence between the conveyance speed and the ultrasonic amplitude. In this case, the conveyance speed is determined according to the output from the encoder 90.

[0035] Next, the control unit 80 checks whether an instruction to stop operation of the bag making and packaging machine 1 has been input in response to a user operation or the like (step S108). The instruction to stop operation is information instructing the bag making and packaging machine 1 to stop its bag making operation. If an instruction to stop operation has not been input (N in step S108), the conveyance control unit 81 and the ultrasonic control unit 82 continue their operations. If an instruction to stop operation has been input (Y in step S108), the ultrasonic control unit 82 stops the ultrasonic operation, and the conveyance control unit 81 stops the conveyance of the packaging material (step S110). Specifically, the ultrasonic control unit 82 instructs the ultrasonic vertical sealing device 60 to stop the ultrasonic vibration. This stops the ultrasonic vibration by the ultrasonic vertical sealing device 60. Furthermore, the conveyance control unit 81 instructs the packaging material feeding device 70 to stop conveyance. This stops the conveyance of the packaging material by the packaging material feeding device 70.

[0036] As described above, in the bag making and packaging machine 1 according to this embodiment, the packaging material feed device 70 conveys the packaging material at a low speed for a certain period of time after the start of packaging material conveyance. Therefore, even during the period when the ultrasonic amplitude is relatively small immediately after the start of ultrasonic vibration and before the ultrasonic amplitude reaches the operating amplitude, ultrasonic vertical sealing can be performed stably.

[0037] It should be noted that the present invention is not limited to the specific embodiments, and various modifications and changes are possible within the scope of the gist of the present invention as defined in the claims.

[0038] In such a first modified example, the transport speed does not have to be constant for a certain period of time after the start of transport. FIG. 6 is an explanatory diagram of the first modified example. FIG. 6 is a graph showing the transport speed, with the horizontal axis representing time and the vertical axis representing the transport speed. As shown in FIG. 6, during a certain period of time after the start of transport (the period from timing t1 to timing t5 in the example of FIG. 6), when the transport speed is set to the operating speed, the transport speed may be controlled to accelerate at an acceleration that is slower than the acceleration from zero to the operating speed. In this case, too, the timing at which the operating speed is reached can be delayed compared to when the operating speed is set at the start of operation. As another example, during a certain period of time, the transport speed may be increased in stages, such as first being set to a first low speed, and then being set to a second low speed that is higher than the first low speed.

[0039] As a second modification, the conveyance control unit 81 may control the conveyance speed so that the conveyance speed gradually increases to the operating speed during the rise time. Here, the rise time is the time required from the start instruction timing t1 to the timing t2 when the ultrasonic vibration reaches the operating amplitude. FIG. 7 is an explanatory diagram of the second modification. FIG. 7 is a graph showing the conveyance speed, with the horizontal axis representing time and the vertical axis representing the conveyance speed. As shown in FIG. 7, in this example, the conveyance speed gradually increases from the start instruction timing t1 to the timing t2 when the operating amplitude is reached. Note that there is a relationship between the ultrasonic amplitude and the conveyance speed to achieve stable ultrasonic vertical sealing. If the acceleration of the conveyance speed is too large, the ultrasonic amplitude cannot keep up, and stable ultrasonic vertical sealing cannot be achieved. Therefore, the acceleration of the conveyance speed in this case is set to an acceleration that allows the increase in ultrasonic amplitude to follow, enabling such stable ultrasonic vertical sealing.

[0040] Furthermore, even in this case, the timing at which the operating speed is reached does not have to coincide with timing t2. As another example, the timing at which the operating amplitude is reached may be set to a timing after t2, and the conveying speed may be controlled to gradually increase based on this timing.

[0041] A third modified example will now be described. When the conveyance of the packaging material is stopped, the packaging material may sag. If conveyance is restarted in this state, the packaging material will advance in the conveyance direction by an amount equal to the sagging amount. In this case, a portion of the packaging material passes through the ultrasonic vertical sealing device 60 without being ultrasonically vertically sealed. In contrast, in this example, the conveyance control unit 81 conveys the packaging material in the reverse conveyance direction a certain distance when the conveyance of the packaging material is stopped. Here, the reverse conveyance direction is the direction opposite to the conveyance direction. As a result, after conveyance is restarted, the area where the ultrasonic vertical seal is not applied can be passed through the ultrasonic vertical sealing device 60 again, thereby applying an ultrasonic vertical seal. Note that the certain distance conveyed in the reverse conveyance direction is preferably shorter than the distance the packaging material is conveyed from when the conveyance speed is set to the operating speed until it actually reaches the operating speed. Note that the timing of the reverse conveyance of the packaging material may be any time after the conveyance has stopped and before the next conveyance is started, and is not limited to when the conveyance of the packaging material has stopped. For example, the reverse conveyance may be performed immediately before the next conveyance is started.

[0042] Furthermore, as another example of the third modified example, the area where the ultrasonic vertical seal is not applied may be horizontally sealed by the subsequent horizontal sealing device 40. This allows stable horizontal sealing to be applied to the area where the ultrasonic vertical seal is not applied. Here, the horizontal sealing device 40 is an example of the second sealing device.

[0043] As a fourth modification, the ultrasonic vibration may be initiated after the start of the packaging material conveyance. FIG. 8 is an explanatory diagram of the fourth modification. FIG. 8(a) is a graph showing changes in ultrasonic amplitude according to this embodiment, with the horizontal axis representing time and the vertical axis representing ultrasonic amplitude. FIG. 8(b) is a graph showing the conveying speed, with the horizontal axis representing time and the vertical axis representing conveying speed. As shown in FIG. 8(b), in this embodiment, the conveying speed starts at start instruction timing t1, as shown in FIG. 8(b), and conveying is performed at a low speed for a certain period of time. Meanwhile, the ultrasonic vibration is initiated at timing t11, which is later than the start instruction timing t1. In other words, the ultrasonic vibration is initiated at a timing after the start of the packaging material conveyance. In this way, by starting the ultrasonic vibration at a timing after the start of the conveyance of the material, it is possible to prevent the seal from becoming dirty due to continuous application of ultrasonic vibration.

[0044] Furthermore, in this case, ultrasonic vertical sealing will not be applied to the area that passed through the ultrasonic vertical sealing device 60 between the start of packaging material conveyance and the start of ultrasonic vibration. Therefore, when the packaging material conveyance stops, the packaging material may be conveyed a certain distance in the reverse conveyance direction. This allows ultrasonic vertical sealing to be applied to the area that will not be ultrasonic vertically sealed after conveyance begins again. Furthermore, instead of conveying the packaging material in the reverse conveyance direction, horizontal sealing by the horizontal sealing device 40 may be applied to the area that will not be ultrasonic vertically sealed. In this case, stable sealing can also be applied to the area that will not be ultrasonic vertically sealed.

[0045] As a fifth variation, the bag-making and packaging machine 1 may be a so-called intermittent machine in which the conveyance of packaging material is temporarily stopped when the bag package is formed, thereby intermittently conveying the packaging material. In this case, when the conveyance is resumed after the temporary stop, the conveyance speed is controlled as described in this embodiment. [Explanation of symbols]

[0046] 1 Bag making, filling and packaging machine 10. Feeding mechanism 30 Forma 40 Horizontal sealing device 50 Filling cylinder 60 Ultrasonic vertical sealing device 61 Ultrasonic Horn 62 Ultrasonic generator 64 Anvil 70 Packaging material feeder 80 Control Unit 81 Transport control unit 82 Ultrasonic control unit

Claims

1. a packaging material feeding device that conveys the packaging material along a conveying direction; an ultrasonic sealing device that applies ultrasonic sealing to the packaging material conveyed by the packaging material feeding device along the conveying direction by using ultrasonic vibrations; a conveyance control unit that controls conveyance by the packaging material feeding device; Equipped with the ultrasonic sealing device starts the ultrasonic vibration simultaneously with or after the packaging material feed device starts conveying the packaging material, The conveying control unit sets the conveying speed for a certain period from the start of conveying by the packaging material feeding device to a low speed that is slower than the operating speed, which is the conveying speed set during packaging operation.

2. The bag-making and packaging machine according to claim 1 , wherein the conveyance control unit sets the conveyance speed to the operating speed after the certain period of time has elapsed.

3. the conveyance control unit gradually increases the conveyance speed after the certain period has elapsed, 2. The bag-making and packaging machine according to claim 1, wherein the ultrasonic sealing device generates the ultrasonic vibrations with an amplitude corresponding to the conveying speed.

4. 2. The bag-making and packaging machine according to claim 1, wherein the packaging material feed device conveys the packaging material a fixed distance in a reverse conveyance direction that is a direction opposite to the conveyance direction after conveyance of the packaging material has stopped or before conveyance of the packaging material starts, and when conveyance starts, starts conveyance in the conveyance direction from a state in which the packaging material has been conveyed the fixed distance in the reverse conveyance direction.

5. The bag-making and packaging machine according to claim 4 , wherein the predetermined distance is shorter than a distance over which the packaging material is conveyed until the conveying speed reaches the operating speed.

6. 2. The bag-making and packaging machine according to claim 1, further comprising a second sealing device that applies a seal that crosses the ultrasonic seal in the area where the ultrasonic seal has been applied for a certain period of time from the start of conveyance of the packaging material.

7. a packaging material feeding device that conveys the packaging material along a conveying direction; an ultrasonic sealing device that applies ultrasonic sealing to the packaging material conveyed by the packaging material feeding device by using ultrasonic vibrations; a conveyance control unit that controls conveyance by the packaging material feeding device; Equipped with the ultrasonic sealing device starts the ultrasonic vibration simultaneously with or after the packaging material feed device starts conveying the packaging material, the conveyance control unit controls the conveyance speed of the packaging material to increase to the set operational speed over a period of time equal to or longer than the rise time required for the amplitude of the ultrasonic vibration to reach the set operational amplitude from the timing of the start of the ultrasonic vibration, The ultrasonic sealing device generates the ultrasonic vibrations having an amplitude corresponding to the conveying speed.

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