JP7576338B2 - Horizontal sealing device for horizontal form fill machine - Google Patents

Description

The present invention relates to a horizontal sealing device in a horizontal form-fill-seal machine that applies horizontal seals to tubular packaging material using a pair of sealing bodies that rotate in opposite directions.

In packaging machines such as horizontal form-fill-and-seal machines, the film (packaging material) is pulled out from a roll of raw material and guided by a bag-making means, with both widthwise edges of the film overlapping in a folded shape to form a cylindrical shape, and vertical seals are applied to the overlapped portions in the film's conveying direction, while horizontal seals that cross the conveying direction are applied to the front and rear positions of each item fed into the cylindrical film to obtain pillow-packaged products. Patent Document 1 proposes a horizontal sealing device that applies horizontal seals to a cylindrical film in a packaging machine, in which a pair of sealing bodies are arranged opposite each other across the conveying path of the cylindrical film, and the pair of sealing bodies are rotated in opposite directions by separate drive motors to sandwich the cylindrical film and apply a horizontal seal when the sealing surfaces of the two sealing bodies mesh with each other.

In the horizontal sealing device of Patent Document 1, in order to remove molten film residue adhering to the sealing surface of the sealing body and residue of an article that adheres when the article is caught in the sealing body, the control means controls the drive of each drive motor based on the output signal from the switching operation when the maintenance mode is set so that the sealing bodies rotate and stop from a stopped state in which the sealing bodies are stopped so that the sealing surfaces are oriented in a position that allows the sealing bodies to be easily cleaned by applying a wire brush to the sealing surfaces of both sealing bodies without getting in the way of each other during cleaning.

Patent No. 5282111

In a configuration in which a pair of seal bodies are rotated by separate drive motors, such as the horizontal sealing device disclosed in Patent Document 1, if the synchronization of the rotational positions is lost for some reason, a set operation is required to align the seal bodies in a synchronous manner. If the seal bodies mesh with each other while remaining asynchronous during this set operation, the seal mesh formed on the seal surface will not be in a correct meshing relationship, and problems such as damage to the seal mesh forming portion may occur.

The object of the present invention is to provide a horizontal sealing device in a horizontal form-fill-seal machine that can perform synchronized set operation of a pair of sealing bodies in a horizontal sealing device that rotates and drives a pair of sealing bodies using separate drive motors.

The horizontal sealing device in the horizontal bag making and filling machine according to the invention of claim 1 of the present application is:
A horizontal sealing device in a horizontal form-fill-seal machine in which a pair of sealing bodies (17, 18) rotate in opposite directions to each other across the conveying path of a tubular packaging material (10) to clamp an article (11) fed into the tubular packaging material (10) at the front and rear of the material to perform a horizontal seal in a direction intersecting the conveying direction of the tubular packaging material (10),
a first drive motor (29) that rotates a first rotating shaft (21) on which one of the seal bodies (17) is disposed;
a second drive motor (32) that rotates a second rotating shaft (23) on which the other seal body (18) is disposed; and
a biasing means (26) for biasing one of the first rotating shaft (21) and the second rotating shaft (23) toward the other to bring the two rotating shafts (21, 23) closer to each other and for separating the two rotating shafts (21, 23) by releasing the biasing force;
and a control means (40) which, upon receiving a request signal for synchronous set operation of the first drive motor (29) and the second drive motor (32), outputs a release signal to the biasing means (26), separates the first rotating shaft (21) and the second rotating shaft (23) to increase the distance between the pair of sealing bodies (17, 18) , and starts synchronous set operation, and outputs a biasing signal to the biasing means (26) when the first rotating shaft (21) and the second rotating shaft (23) reach a synchronized position with no deviation in rotation phase between them during the synchronous set operation , and moves the first rotating shaft (21) and the second rotating shaft (23) closer to each other so that the distance between the sealing bodies (17, 18) is such that the pair of sealing bodies (17, 18) can sandwich the tubular packaging material (10) and perform a transverse seal.
According to the invention of claim 1, the mutual distance between the pair of seal bodies is increased by a signal for performing synchronous set operation of the first and second drive motors, so that even if the seal bodies rotate in different directions or in different phases during synchronous set operation, the seals formed on the seal surfaces of the seal bodies do not mesh with each other in a different state from the correct meshing state, and the seals on the seal surfaces are prevented from being damaged, such as being crushed. Furthermore, even if the seal bodies rotate to pass the meshing position during synchronous set operation, the seal bodies do not clamp the tubular packaging material that is stopped during conveyance and push it back to the upstream conveyance direction, or pull it to the downstream conveyance direction and tear the packaging material. Furthermore, it is possible to prevent a problem in which the seal bodies rotating during the set operation indirectly come into contact with the article being supplied to the tubular packaging material, causing the position of the article in the tubular packaging material to be shifted.

In the invention according to claim 2, there is provided a first support member (22a, 22b) which rotatably supports the first rotating shaft (21) on both shaft end sides of one of the seal bodies (17) of the first rotating shaft (21);
and second support members (24a, 24b) for rotatably supporting the second rotating shaft (23) on both shaft end sides of the other seal body (18) of the second rotating shaft (23),
The biasing means (26) is characterized in that it is configured to bias one of the first support members (22a, 22b) and the second support members (24a, 24b) toward the other.
According to the invention of claim 2, by moving the support members supporting the rotating shaft on both sides of the sealing body closer to or farther away from each other, the pair of sealing bodies can be moved closer to or farther away without changing the posture of the pair of sealing bodies, and the clamping condition of the tubular packaging material does not change, resulting in poor lateral sealing.

In the invention according to claim 3, the second support members (24a, 24b) are supported below the first support members (22a, 22b) so as to be movable toward and away from each other,
The base member (15) disposed below the second support members (24a, 24b) is provided with the biasing means (26) for biasing the second support members (24a, 24b) against the first support members (22a, 22b).
According to the invention of claim 3, by arranging the biasing means so as to be housed in the empty space below the horizontal sealing device, it is possible to ensure an effectively usable spatial area above the device.

In the invention according to claim 4, one of the seal bodies (17) is configured as a horn (17) that is ultrasonically vibrated by a vibration generating means (19), and the other seal body (18) is configured as an anvil (18),
The device is characterized in that the tubular packaging material (10) held between the horn (17) and the anvil (18) is transversely sealed by ultrasonic vibration.
According to the invention of claim 4, the tubular packaging material is sealed laterally using ultrasonic vibrations, so the sealing body does not become hot. Therefore, when the sealing body stops in relation to the timing of clamping the tubular packaging material, there is no need to take measures to prevent burns to the packaging material by preventing the sealing body from coming into contact with the tubular packaging material. Furthermore, when an air cylinder is used as the biasing means, a compact cylinder with a short biasing stroke can be selected, making it possible to miniaturize the device.

According to the present invention, when performing synchronous set operation to synchronously align the drive motors that rotate each seal body, it is possible to perform good synchronous alignment without causing problems such as damage to the seal forming parts on the seal body or misalignment of the items in the cylindrical packaging material.

FIG. 2 is a schematic side view of a horizontal sealing device. FIG. 2 is a schematic front view of the transverse sealing device showing the state in which the horn and the anvil are close to each other. FIG. 2 is a schematic front view of the transverse sealing device, showing the state in which the horn and the anvil are separated from each other. FIG. 2 is a schematic perspective view of a horizontal sealing device, showing some members in a see-through manner. FIG. 4 is a control block diagram of the horizontal sealing device.

Next, a preferred embodiment of the horizontal sealing device in the horizontal form-fill-seal machine according to the present invention will be described below with reference to the attached drawings.

A horizontal bag making and filling machine (packaging machine) includes a bag making means for forming a strip of film (packaging material) pulled out from a roll into a tubular film (tubular packaging material) 10 by overlapping both longitudinal end edges in a folded shape, a supply conveyor for supplying items 11 to the tubular film 10 at predetermined intervals, a vertical sealing device for applying a vertical seal in the film conveying direction to the overlapped portion of the tubular film 10 overlapped in the folded shape, a film conveying means for clamping the overlapped portion of the tubular film 10 and conveying the tubular film 10 toward the vertical sealing device, and a horizontal sealing device for clamping the tubular film 10 at the front and rear positions of the items 11 supplied at predetermined intervals into the tubular film 10 and applying a horizontal seal and cutting in a direction (width direction) intersecting the film conveying direction. The horizontal sealing device horizontally seals and cuts the tubular film 10 with the vertical seal applied to the overlapped portion by the vertical sealing device folded over the bag body. The packaging machine is also provided with a transport conveyor 12 and an unloading conveyor 13 that support the item 11 from below via the tubular film 10 and transport it downstream, before and after the film transport direction of the horizontal sealing device, and is configured so that the item 11 is transported to the next process by the unloading conveyor 13 as a bagged product (pillow packaged product) that has been transversely sealed and cut and separated from the upstream tubular film 10.

As shown in Figures 1 to 4, the horizontal sealing device has a base member 15 arranged on a bottom frame 14, and a sealing unit 20 arranged on the base member 15, the sealing unit 20 comprising a pair of sealing bodies, a horn 17 and an anvil 18, which rotate in opposite directions across the transport path of the tubular film 10, and a vibration generating means 19 that ultrasonically vibrates the horn 17. The sealing unit 20 includes a pair of first support members 22a, 22b that rotatably support a first rotating shaft 21 extending to the left and right of the horn 17, and a pair of second support members 24a, 24b that rotatably support a second rotating shaft 23 extending to the left and right of the anvil 18, and the corresponding right first support member 22a and right second support member 24a, and the left first support member 22b and left second support member 24b are arranged opposite to each other on the left and right sides of the horn 17 and the anvil 18 so that the first rotating shaft 21 and the second rotating shaft 23 can be moved toward and away from each other. In this embodiment, the horn 17 is arranged on the upper side across the conveying path, and the anvil 18 is arranged on the lower side, so that the lower surfaces (opposing surfaces) of the first support members 22a, 22b and the upper surfaces (opposing surfaces) of the second support members 24a, 24b face each other at a predetermined interval. The sealing unit 20 also includes a guide means 25 that supports one of the support members 24a, 24b facing the left and right of the horn 17 and the anvil 18 so that it can move toward and away from the other support members 22a, 22b, and a biasing means 26 consisting of an air cylinder that biases the one of the support members 24a, 24b movably supported by the guide means 25 toward the other support members 22a, 22b. In this embodiment, the second support members 24a, 24b supporting the anvil (the other seal body) 18 are supported movably along the guide means 25 consisting of the guide shaft 36 with respect to the first support members 22a, 22b supporting the horn (one seal body) 17, and the second support members 24a, 24b are configured to be movable toward and away from the first support members 22a, 22b, and the second support members 24a, 24b are configured to be urged toward the first support members 22a, 22b by the urging means 26.

As shown in Figures 2 and 4, the sealing unit 20 comprises a first drive motor 29 consisting of a servo motor arranged on a connecting member 27 connecting the pair of first support members 22a, 22b and driving the first rotating shaft 21 via a first linkage mechanism 28 consisting of a belt-pulley transmission means, and a second drive motor 32 consisting of a servo motor arranged on a support base 30 on which the pair of second support members 24a, 24b are erected and driving the second rotating shaft 23 via a second linkage mechanism 31 consisting of a belt-pulley transmission means, and the horn 17 and the anvil 18 are driven to rotate in opposite directions to each other by both drive motors 29, 32, synchronizing their rotational positions and rotational speeds. The vibration generating means 19 is supported on the connecting member 27, and the vibration generating means 19 includes a converter that generates ultrasonic waves and a booster that amplifies ultrasonic waves, and is configured to ultrasonically vibrate the horn 17 at a predetermined amplitude. The tubular film 10 transported by the film transport means is clamped at a predetermined pressure between the horn 17 and the anvil 18, and a horizontal seal is applied to the tubular film 10 in the width direction that intersects with the transport direction by ultrasonic vibration.

As shown in Figures 1 to 4, the horn 17 is rotatably supported by the pair of first support members 22a, 22b connected in a gate shape by the connecting member 27 at the shaft end side of the first rotating shaft 21 via bearings. The horn 17 has a plurality of seal heads 33 (two at 180° intervals in this embodiment) radially provided at a predetermined angle on the first rotating shaft 21, and a pair of seal surfaces are provided on the outer circumferential surface of each seal head 33, separated in the front-rear width direction, which is the rotation direction of the seal head 33, sandwiching a groove portion recessed from the outer circumferential surface toward the rotating shaft. The anvil 18 is rotatably supported by the pair of second support members 24a, 24b via bearings at the shaft end side of the second rotating shaft 23. The anvil 18 has seal bars 34 that are paired with the seal heads 33 of the horn 17 and are provided protruding from the second rotating shaft 23 at predetermined angles. A cutting means 35 is disposed in the anvil 18, and a through hole is formed at the protruding end of the seal bar 34 so that the cutting means 35 can be inserted and removed. On both sides of the through hole of each seal bar 34, a sealing surface that forms a pair with the sealing surface of the horn 17 is formed so as to extend in the width direction of the tubular film 10. Then, at the front and rear positions where the articles 11 supplied at predetermined intervals into the tubular film 10 are sandwiched, the tubular film 10 being conveyed is clamped by the seal head 33 of the rotating horn 17 and the seal bar 34 of the anvil 18, and the sealant of the packaging material melts due to the ultrasonic vibration emitted from the horn 17, and a sealed horizontal seal portion is formed that crosses the conveying direction of the tubular film 10. Each sealing surface of the seal head 33 and the seal bar 34 is provided with a seal stitch forming portion that forms a predetermined seal stitch in the horizontal seal portion of the tubular film 10 when horizontal sealing.

1, the cutting means 35 is provided with a blade portion 35a on each seal bar side, and is connected to a reciprocating means (not shown) arranged on the support base 30 and driven by a motor such as a servo motor that moves the cutting means 35 back and forth in the radial direction. The reciprocating means is configured to operate the cutting means 35 at the timing when the tubular film 10 is clamped by the sealing surface, so that the blade portion 35a momentarily protrudes in the radial direction from the sealing surface of the anvil 18, and cuts the tubular film 10 clamped by the sealing surface in the width direction of the tubular film 10. When the cutting means 35 protrudes the blade portion 35a from the sealing surface of the anvil 18 to cut the tubular film 10, the blade portion 35a is received in the groove portion of the horn 17 without contacting it.

1 and 2, the base member 15 is provided with the guide means 25, each of which includes a pair of guide shafts 36, 36 spaced apart in the forward and backward directions in the film transport direction, on both the left and right sides of the transport path for the tubular film 10, and the first support members 22a, 22b and the second support members 24a, 24b, which face each other in the vertical direction, are supported by each guide means 25. The guide shaft 36 has a small diameter portion extending upward from a large diameter portion 37 of a predetermined height dimension erected on the base member 15, and the extending end of the guide shaft 36 is fixed to the lower portion of the first support members 22a, 22b, and the first support members 22a, 22b are supported in a fixed position by the pair of guide shafts 36, 36 relative to the base member 15. The second support members 24a, 24b are supported between the large diameter portions 37, 37 of the pair of guide shafts 36, 36 and the first support members 22a, 22b so as to be movable in the vertical direction along the guide shafts 36, 36 so as to approach and move away from the first support members 22a, 22b. Air cylinders 38 constituting the biasing means 26 are respectively disposed on the base member 15 at intermediate positions of the pair of guide shafts 36, 36 spaced apart in the front-rear direction in the film transport direction, and the piston rods extending upward from both air cylinders 38, 38 are respectively connected so as to be able to press upward directly below the second support members 24a, 24b disposed on the support base 30. In other words, the second support members 24a, 24b are configured to be biased from below by the air cylinders 38 toward the first support members 22a, 22b with a predetermined pressure.

As shown in FIG. 5, the two air cylinders 38, 38 are connected to an electromagnetic valve 44 which switches the air flow path from the air supply source to extend and retract the piston rods of the air cylinders 38, 38, and an electro-pneumatic regulator 39 which controls the air pressure. The air cylinders 38, 38 are switched between a state in which the piston rods extend from the cylinder body and urge the second support members 24a, 24b toward the first support members 22a, 22b by a biasing force pressure-controlled by the electro-pneumatic regulator 39, and a state in which the piston rods are retracted into the cylinder body to release the biasing force of the second support members 24a, 24b and separate the second support members 24a, 24b from the first support members 22a, 22b. That is, in the biased state by the air cylinders 38, 38, as shown in Fig. 2, the distance between the horn 17 supported by the first support members 22a, 22b via the first rotating shaft 21 and the anvil 18 supported by the second support members 24a, 24b via the second rotating shaft 23 becomes closer to each other, enabling the tubular film 10 to be clamped by the seal head 33 and the seal bar 34. In addition, in the biased state by the air cylinders 38, 38, as shown in Fig. 3, the distance between the horn 17 supported by the first support members 22a, 22b via the first rotating shaft 21 and the anvil 18 supported by the second support members 24a, 24b via the second rotating shaft 23 increases, so that the seal head 33 and the seal bar 34 are separated to a position where they do not mesh with each other. In addition, when the air cylinders 38, 38 are in a de-energized state, the blade portion 35a is positioned at a protruding position from the sealing surface of the anvil 18, and the blade portion 35a protruding from the sealing surface of the anvil 18 is set to a distance between the horn 17 and the anvil 18 such that the blade portion 35a does not come into contact with the seal head 33 of the horn 17 or the outer edge of the horn 17 even when the horn 17 and the anvil 18 rotate in different phases. In this embodiment, the biasing means 26 is composed of the air cylinders 38, 38, the electropneumatic regulator 39, and the solenoid valve 44.

5, the first drive motor 29, the second drive motor 32, the solenoid valve 44, the electropneumatic regulator 39, and the notification means 41 such as a buzzer or a lamp are connected to the control means 40 of the packaging machine. In addition, the control means 40 is connected to various switches such as a power switch 42 and a start switch 43 for starting the operation of the packaging machine, and various sensors for detecting abnormalities in the packaging machine (during operation, etc.). When a synchronization error signal (a request signal for synchronous set operation) is input to the control means 40 when the position synchronization state of the rotation phase between the horn 17 and the anvil 18 is lost during operation or stop of the packaging machine, or when a request signal for synchronous set operation between the horn 17 and the anvil 18 is input to the control means 40 under various other conditions, the control means 40 displays error information on the screen of a display such as an operation panel and notifies the user to perform synchronous set operation. When a request signal for synchronous set operation is input to the control means 40, the control means 40 outputs a deactivation signal to the solenoid valve 44, deactivating the two air cylinders 38, 38 and widening the gap between the horn 17 and the anvil 18, causing the horn 17 and the anvil 18 to enter a standby state with the positional synchronization state of the rotation phases of the horn 17 and the anvil 18 lost. After appropriate measures are taken to address the cause of the positional synchronization state being lost, the synchronous set operation of the horn 17 and the anvil 18 is executed. The synchronous set operation is executed by the operator operating the start switch of the packaging machine after the error notification is released. The positions where both the sealing surfaces of the seal head 33 and the seal bar 34 face horizontally are set as the origin positions of the horn 17 and the anvil 18. The synchronous set operation rotates the drive motors 29 and 32 at low speeds, and the horn 17 and anvil 18 reach the origin positions, causing the first drive motor 29 and the second drive motor 32 to stop rotating. When the synchronous set operation is completed, the control means 40 outputs an energizing signal to the solenoid valve 44, and the two air cylinders 38 and 38 energize the second support members 24a and 24b toward the first support members 22a and 22b while maintaining a predetermined pressure with the electropneumatic regulator 39, thereby narrowing the distance between the horn 17 and the anvil 18, and restoring the state in which the tubular film 10 can be clamped between the seal head 33 and the seal bar 34 to perform a lateral seal on the tubular film 10. The applied pressure is maintained at a predetermined pressure by the electropneumatic regulator 39.

Here, situations in which the rotational phase position synchronization between the horn 17 and the anvil 18 is lost while the packaging machine is in operation or stopped with the power on include, for example, a situation in which an item 11 is caught between the horn 17 and the anvil 18, putting a load on the first and second drive motors 29, 32 and causing a misalignment; a situation in which a worker manually changes the rotational positions of the horn 17 and the anvil 18 during maintenance work while the machine is stopped, causing a misalignment; and a situation in which a transport problem occurs in the tubular film 10 for some reason, causing a misalignment with the lateral sealing device. The positional synchronization state of the rotation phase between the horn 17 and the anvil 18 is lost, i.e., the rotation angle signal of the encoder provided on the drive motor 29, 32 is deviated when the origin sensor 45a, 45b arranged on the rotating parts of the first and second drive motors 29, 32 and the horn 17 and the anvil 18 detects the difference, or when a registration mark detection failure signal on the tubular film 10 is sent (when the registration mark cannot be detected or cannot be detected at a certain time interval), or when the control means 40 judges that the synchronization state is lost due to a malfunction of each drive motor 29, 32 itself, the control means 40 processes it as if a request signal for synchronous set operation has been input. In other words, when the control means 40 judges that various types of synchronization deviations have occurred based on signals from various detection devices such as the encoders and registration mark sensors provided on the drive motors 29, 32 and the film transport means, it outputs a de-energization signal to the solenoid valve 44 and issues a notice to encourage synchronous set operation.

When the power switch 42 is turned on to prepare the packaging machine for operation, a power ON signal (a request signal for synchronous set operation) is input to the control means 40, and a signal for executing a synchronous set operation is output to each synchronous operation mechanism prior to packaging operation. When a request signal for synchronous set operation is input to the control means 40, a display is displayed on the screen of the operation panel prompting the operator to perform a set operation operation. If the operator is ready to operate, the synchronous set operation is started by pressing the start switch 43 of the packaging machine. In the synchronous set operation, the servo motors that drive the supply conveyor, film transport means, and horizontal sealing device, each of which is driven and controlled by a servo motor, are activated, and the synchronous set operation of each mechanism is performed at a low speed. After switching to different packaging conditions due to a product type change, etc., the control means 40 judges the operation start signal output when the start switch 43 is pressed ON as a request signal for synchronous set operation and processes it. When a request signal for synchronous set operation, such as a power ON signal or a signal to start operation after a product type change, is input (the control means 40 receives the request signal), the control means 40 outputs a switching signal (force release signal) to the solenoid valve 44, causing the piston rod of the cylinder to retract and release the force of the second support members 24a, 24b on the first support members 22a, 22b.

Next, we will explain the operation of the horizontal sealing device in the horizontal form-fill-seal machine of the embodiment.

When the control means 40 receives a request signal for synchronous set operation during operation or while the packaging machine (horizontal bag-filling machine) is stopped after the power switch 42 is turned on, or when various types of synchronization states are detected based on signals from various detection devices, and the control means 40 determines that the rotation phase of the horn (one sealing body) 17 and the anvil (the other sealing body) 18 of the horizontal sealing device is out of sync (determines that a request signal for synchronous set operation has been received), if the machine is in operation, it stops each mechanism and outputs a deactivation signal to the solenoid valve 44, and if the machine is stopped, it outputs a deactivation signal to the solenoid valve 44. When a deactivation signal is input to the solenoid valve 44, the piston rods of the two air cylinders 38, 38 are operated to be drawn into the cylinder body, and the second support members 24a, 24b are separated from the first support members 22a, 22b, thereby increasing the distance between the horn 17 and the anvil 18 (see FIG. 3). Then, when the operator presses the start switch 43 to start the synchronous set operation, the control means 40 operates the first drive motor 29 and the second drive motor 32 at a low speed to perform a synchronous set operation in which the horn 17 and the anvil 18 are returned to the original position so that there is no phase shift in the rotational positions of the horn 17 and the anvil 18 and are in a synchronous position. When the synchronous set operation is completed, the control means 40 outputs an energizing signal to the solenoid valve 44, which operates the two air cylinders 38, 38 so that the piston rods extend from the cylinder bodies and energize the second support members 24a, 24b toward the first support members 22a, 22b, automatically reducing the distance between the horn 17 and the anvil 18, and the sealing head 33 and the sealing bar 34 are able to clamp the tubular film 10 with a predetermined pressure, and the packaging machine is ready to start operation (see FIG. 2).

In the horizontal sealing device of the embodiment, when a request signal for synchronous set operation is input to the control means 40, such as when the positional synchronization state of the rotational positions of the horn 17 and the anvil 18 is lost, the distance between the horn 17 and the anvil 18 is increased, and the first drive motor 29 and the second drive motor 32 are operated at a low speed to perform synchronous set operation. In other words, since the sealing surface of the horn 17 and the sealing surface of the anvil 18 are spaced apart at a certain distance without being in a meshed state, the seal head 33 of the horn 17 and the seal bar 34 of the anvil 18 do not collide while being in different rotational phases, and it is possible to prevent the seal surfaces from contacting each other and interfering with each other, causing damage such as crushing or loss of the seal mesh forming portion. In addition, even if the film transport is stopped during synchronous set operation, when the seal head 33 of the horn 17 and the seal bar 34 of the anvil 18 rotate to return to their original positions, the tubular film 10 is clamped by both seal surfaces and is not pulled excessively downstream in the transport direction, causing it to tear, or pulled back upstream in the transport direction, causing it to shrink, preventing the object 11 supplied into the tubular film 10 from becoming misaligned.

In the horizontal sealing device of the embodiment, the first support members 22a, 22b that rotatably support the first rotating shaft 21 on both sides of the horn 17 are supported so that they can move toward and away from the second support members 24a, 24b that rotatably support the second rotating shaft 23 on both sides of the anvil 18. By moving the second support members 24a, 24b toward and away from the first support members 22a, 22b, the distance between the horn 17 and the anvil 18 can be changed. This allows the horn 17 and the anvil 18 to move toward and away from each other without changing their posture, and the state in which the tubular film 10 is clamped does not change, resulting in poor horizontal sealing.

The air cylinders 38, 38 of the biasing means 26 are configured to be disposed on the base member 15 disposed below the second support members 24a, 24b, so that the air cylinders 38, 38 can be disposed to be housed in the lower empty space of the lateral sealing device, and an effectively usable spatial area can be secured above the device without the air cylinders 38, 38 protruding above the sealing unit 20. In addition, since the ultrasonic sealing method is used to transversely seal the tubular film 10 by ultrasonic vibration using the horn 17 and anvil 18, the horn 17 and anvil 18 do not become hot, and there is no need to take measures to prevent burns to the packaging material by preventing the horn 17 and anvil 18 from contacting the tubular film 10 when the horn 17 and anvil 18 stop in relation to the timing of clamping the tubular film 10. In other words, there is no need to use air cylinders 38, 38 with a large spring stroke to prevent burns to the tubular film 10, and a compact cylinder with a small spring stroke can be selected, allowing the device to be made more compact. Also, when performing maintenance on the horizontal sealing device, the seal head 33 of the horn 17 and the seal bar 34 of the anvil 18 do not increase in temperature due to heating, so maintenance work can be started immediately, shortening the maintenance response time.

The synchronous set operation of the horizontal sealing device can be performed independently of other mechanisms without adversely affecting the tubular film 10 while transport is stopped, so there is no need to transport and send the tubular film 10, which has been set in advance in accordance with the rotational movement of the horn 17 and the anvil 18, downstream, eliminating the waste of film due to the synchronous set operation. Furthermore, even if the synchronous set operation of the horizontal sealing device is performed separately from the synchronous alignment transport operation of the film transport means when performing synchronous alignment with each mechanism such as the supply conveyor and film transport means, it is possible to prevent inconveniences such as the tubular film 10 being torn or the spacing between objects in the tubular film being shifted, as in the case when the film transport is stopped, and the device can be placed in a standby state in which it can immediately transition to normal operation after synchronous alignment.

In this embodiment, in a horizontal sealing device that employs a cutting means 35 of the so-called "thrust-off" type, in which a cutting blade housed inside one of the sealing bodies 18 protrudes from the sealing surface at the timing when the sealing surfaces of the pair of sealing bodies 17, 18 mesh with each other to cut the tubular film 10 held by the sealing surfaces, if the positional synchronization of the rotational phase between the sealing bodies is lost, it is expected that the tip of the cutting blade will rotate while protruding from the sealing surface of one of the sealing bodies, and come into contact with and interfere with the other sealing body. In the synchronous set operation of the horizontal sealing device of the embodiment, the piston rods of the two air cylinders 38, 38 are retracted into the cylinder body until the cutting means 35 is synchronized, and the mutual distance between the horn 17 and the anvil 18 is expanded. Therefore, during the rotational state until the horn 17 and the anvil 18 are synchronized during the synchronous set operation, the cutting portion 35a of the cutting means 35 protruding from the sealing surface of the seal bar 34 on the anvil 18 can be prevented from contacting the seal head 33 or the outer edge of the horn 17 other than the groove portion when rotating in a state where the rotation phase with the horn 17 is not aligned, and damage to the cutting means 35 and the horn 17 can be avoided.

(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 are not limited to the following modifications, and various embodiments can be adopted within the scope of the gist of the present invention.
(1) Sealing unit 20 is not limited to an ultrasonic sealing type consisting of horn 17 and anvil 18, but may be a heat sealing type in which a heat source such as a heater is disposed in the sealing body. When a heat sealing type sealing body is used, the separation position of the pair of sealing bodies by air cylinders 38, 38 can be set to a range in which the rotation trajectory of the sealing bodies does not come into contact with tubular film 10, thereby preventing the sealing bodies from coming into contact with or clamping the film, thereby melting the film.
(2) The sealing heads 33 and sealing bars 34 provided on the rotating shafts 21, 23 are not limited to a configuration in which two are provided at 180 degree intervals, and one or three or more sealing heads 33 and sealing bars 34 may be provided radially from the rotating shafts 21, 23, and the blade portion 35a of the cutting means 35 may correspond to the number of sealing bars 34 provided.
(3) The pair of sealing bodies (the horn 17 and the anvil 18) may be arranged in a left-right relationship rather than a top-bottom relationship, and a configuration in which the rotation shafts 21, 23 are arranged horizontally or vertically may be adopted.
(4) The direction in which one of the support members 24a, 24b is biased toward the other of the support members 22a, 22b may be from top to bottom. In addition, when the first support members 22a, 22b and the second support members 24a, 24b are arranged side by side, the biasing means 26 may be arranged to bias one of the support members toward the other.

(5) The biasing means 26 may be implemented by various means, such as a mechanism that switches the pair of seal bodies between a separated state and a close state by connecting a drive motor to a cam lever or a link mechanism.
(6) Instead of the cutting means 35 which uses a thrust type that protrudes from the sealing surface of the sealing bar 34, a contact-cut type cutting means can be used in which a cutting blade protruding from the sealing surface and a flat receiving surface of a receiving blade provided on the other sealing surface push through the tubular film 10.
(7) The reciprocating means for reciprocating the cutting means 35 is not limited to a configuration operated by a motor, but may be a configuration in which the cutting means 35 is reciprocated by a mechanical linkage means such as a cam link mechanism, an air cylinder, or other reciprocating means in accordance with the rotation of the anvil 18.

REFERENCE SIGNS LIST 10 Cylindrical film (cylindrical packaging material), 11 Article, 15 Base member, 17 Horn (sealing body), 18 Anvil (sealing body), 19 Vibration generating means, 21 First rotating shaft, 22a, 22b First support member, 23 Second rotating shaft, 24a, 24b Second support member, 26 Pressing means, 29 First drive motor, 32 Second drive motor, 40 Control means

Claims (4)

A horizontal sealing device in a horizontal form-fill-seal machine in which a pair of sealing bodies rotate in opposite directions to each other across a conveying path of a tubular packaging material to clamp an article fed into the tubular packaging material at the front and rear of the material and apply a horizontal seal in a direction intersecting the conveying direction of the tubular packaging material,
a first drive motor that rotates a first rotating shaft on which one of the seal bodies is disposed;
a second drive motor that rotates a second rotating shaft on which the other seal body is disposed; and
a biasing means for biasing one of the first rotating shaft and the second rotating shaft toward the other to bring the two rotating shafts closer to each other and for separating the two rotating shafts by releasing the biasing force;
and a control means for receiving a request signal for synchronous set operation of the first drive motor and the second drive motor, outputting a release signal to the biasing means, and separating the first and second rotating shafts to increase the distance between the pair of sealing bodies and start synchronous set operation, and when the first and second rotating shafts reach a synchronized position with no deviation in rotational phase during the synchronous set operation, outputting a biasing signal to the biasing means, and bringing the first and second rotating shafts closer together so that the distance between the sealing bodies is sufficient to sandwich a tubular packaging material between the pair of sealing bodies and perform a lateral seal. a first support member that rotatably supports the first rotating shaft at shaft end sides on both sides of one of the seal bodies of the first rotating shaft;
a second support member that rotatably supports the second rotating shaft at both shaft end sides of the other seal body of the second rotating shaft,
2. The horizontal sealing device in a horizontal bag form-fill-seal machine according to claim 1, wherein the biasing means is configured to bias one of the first support member and the second support member toward the other. The second support member is supported below the first support member so as to be movable toward and away from the first support member,
3. The horizontal sealing device in a horizontal bag form-fill-seal machine according to claim 2, wherein the biasing means for biasing the second support member against the first support member is provided on a base member disposed below the second support member. One of the sealing bodies is configured as a horn that is ultrasonically vibrated by a vibration generating means, and the other sealing body is configured as an anvil,
A horizontal sealing device in a horizontal bag making and filling machine described in any one of claims 1 to 3, characterized in that it is configured to apply a horizontal seal by ultrasonic vibration to the tubular packaging material clamped between the horn and the anvil.

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