JP7324489B2 - Vertical sealing device in a vertical form-fill-seal machine - Google Patents

Description

This invention is a vertical type in which a tubular packaging material is formed from a belt-shaped packaging material, a bag is formed from the tubular packaging material, and a product filled through a bag-making and filling cylinder is packaged in the bag. In a form-fill-seal machine, the present invention relates to a vertical sealing device for forming a strip-shaped packaging material into a cylindrical packaging material by sealing both side edge portions of the strip-shaped packaging material running on the outer peripheral surface of the form-filling tube.

Conventionally, as a form-fill-seal machine, an intermittent operation vertical form-fill-seal machine as disclosed in Patent Document 1 has been widely used. FIG. 4 is a perspective view schematically showing an example of such a vertical form-fill-seal machine. In the vertical form-fill-seal packaging machine 50 shown in FIG. 4, the paper feed belts 53a and 53b intermittently feed the band-shaped packaging material Fw, and the band-shaped packaging material Fw is intermittently fed once to produce the bag package. Only the length of one bag is sent. During this feeding, the band-shaped packaging material Fw is bent by a former 51 so as to be wound around a bag-making and filling tube 52, and the widthwise side edge portions fe, fe of the band-shaped packaging material Fw are bent. It is molded into a substantially cylindrical shape that is overlapped.

The vertical sealing device 54 includes a vertical preheating heater block 57 and a vertical heater block 58 each containing a heater for heating. The vertical sealing device 54 presses and heats the overlapped side edge portions fe, fe of the belt-shaped packaging material Fw from the left and right directions between the heater blocks 57, 58, thereby performing the vertical sealing Sc. The belt-shaped packaging material Fw is formed into a cylindrical packaging material Ft by this heat sealing. The horizontal sealing device 55 includes horizontal heater blocks 56a and 56b containing heaters (not shown). A horizontal seal Se is formed on the cylindrical packaging material Ft. A product, which is an item to be packaged, is put into the packaging machine from above, and is passed through a bag-making and filling tube 52 to be filled into a cylindrical packaging material Ft whose bottom is sealed by a horizontal seal Se.

The cylindrical packaging material Ft filled with the product with the vertical seal Sc and the horizontal seal Se applied is intermittently fed for one bag, and further the bag head and the next are fed by the horizontal heater blocks 56a and 56b. A horizontal seal Se is applied to the bottom of the bag and cut at the center of the horizontal seal Se by a cutting blade (not shown) incorporated in the horizontal sealing device 55 to manufacture the bag package Bp. By repeating the feeding of the packaging material, the formation of vertical and horizontal seals, and the filling of the product at appropriate timings, bag packages containing the products in the bags are continuously manufactured.

The schematic structure of the vertical sealing device 54 provided in the vertical form-fill-sealing machine 50 is shown in FIG. 5, which is a plan view, and FIG. 6, which is a perspective view. A vertical preheating heater block 57 of the vertical sealing device 54 is fixed to the vertical sealer arm 63 via one bracket 59 so as to occupy a position slightly contacting the packaging material. The vertical sealer arm 63 is appropriately attached to the machine frame so as to be openable and closable so that it can be accessed from the front side of the vertical form-fill-seal machine 50 . The vertical preheating heater block 57 has a role of preheating the overlapped side edge portions fe, fe of the substantially cylindrically curved packaging material, and the preheating temperature is such that the packaging material is not thermally deformed. set to a low temperature.

A vertical heater block 58 of the vertical sealing device 54 has a mounting plate 62 attached to the rear side thereof, which is guided by two slide shafts 60, 60 parallel to each other and extending in the lateral direction via sleeves 61, 61. As a result, it is configured to be movable forward and backward toward the vertical preheating heater block 57 on the fixed side. The slide shafts 60, 60 are arranged through the mounting plate 62, and between one bracket 59 that fixes the vertical preheating heater block 57 and the other bracket 59 that is arranged away from the mounting plate 62. It is hung over and attached. The vertical heater block 58 is set to a high temperature at which the sealing material of the packaging material is sufficiently welded. The vertical sealing device 54 is in an open state in which it occupies a position spaced apart from the packaging material except during the sealing operation. , fe are sandwiched and pressed, and both side edge portions fe, fe are pressed and heated between the heat sealing surfaces 57a, 58a of both heater blocks 57, 58 to perform heat sealing. to form a vertical seal Sc (FIG. 4).

In the vertical form-fill-sealing machine 50, an air cylinder device 64 is used as a driving device for opening and closing the vertical sealing device 54 (that is, advancing and retracting the vertical heater block 58). The air cylinder device 64 is arranged near the vertical sealer arm 63 offset from the heater blocks 57 and 58 toward the front side of the vertical form-fill-seal packaging machine 50 . The air cylinder device 64 has a cylinder 65 fixedly attached to the back surface of one bracket 59 on the vertical preheating heater block 57 side. The air cylinder device 64 advances (closes) and retreats (opens) a piston rod 66 as an output member by supplying and discharging compressed air. The tip of the piston rod 66 is attached to a mounting plate fixed to the back side of the vertical heater block 58, and has a structure for directly driving the vertical heater block 58. As shown in FIG.

In the air cylinder device 64, the piston rod 66 is switched between advancing and retreating by operating an electromagnetic valve in response to a vertical sealer opening/closing control signal from the control means of the packaging machine to switch the supply/exhaust direction of the compressed air. be able to. In the illustrated example, the vertical heater block 58 is closed with respect to the vertical preheating heater block 57 by retracting the piston rod 66 in the direction in which the mounting plate 62 is drawn. Also, by adjusting the supply/discharge amount of compressed air with a flow control valve, the operating speed of the piston rod 66 can be adjusted. Furthermore, by detecting the position of the piston rod 66, the control means of the packaging machine can control the operation timing of the vertical heater block 58 and the like.

In the belt-shaped packaging material Fw in which the cylinder making device (former) 51 is bent, the main belt portions other than the side edge portions fe, fe of the belt-shaped packaging material Fw surround the outer peripheral surface of the bag-making and filling tube 52, The side edge portions fe, fe are located in the immediate vicinity of the outer peripheral surface of the bag-making and filling cylinder 52, stand up from the main belt portion, and face each other. The air cylinder device 64 for driving the vertical seal device 54 needs to have a sufficiently wide air pressure receiving area because it is necessary to sandwich both side edge portions fe, fe with a sufficient pressure. The cylinder diameter of the air cylinder device 64 is correspondingly increased, and a sufficient space for arranging the air cylinder device 64 is required. However, as the size of the air cylinder device 64 increases, the space in front of the bag-making, filling, and packaging tube 52 of the vertical bag-making, filling, and packaging machine 50 also becomes large, and the vertical bag-making, filling, and packaging machine including the front transparent panel covering it also becomes large. 50 gets bigger.

A line of action (driving force action line) L<b>3 of the force in the direction in which the air cylinder device 64 pulls the mounting plate 62 by the piston rod 66 coincides with the center line of the piston rod 66 . On the other hand, a line of action (seal center line of action) L4 that is the center of the sealing pressure applied to both side edge portions fe, fe by the vertical heater block 58 (received by the vertical preheating heater block 57) is pass through the centers of the heater surfaces 57a and 58a provided at the tips of the . Therefore, the lines of action L3, L4 are offset by a distance D2.

Due to this offset, when the air cylinder device 64 operates to sandwich the both side edge portions fe, fe, a bending moment M2 is generated in the vertical preheating heater block 57 and the vertical heater block 58, 62 is also slightly deformed, and the heater surfaces 57a and 58a are deformed in directions away from each other on the tip end side. As a result, uniform pressure is not applied to the heater surfaces 57a and 58a, and a portion of the seal pressure is partially weakened. Due to forces and frictional forces, rocking or twisting movements occur, causing wear to the sliding parts during repeated sliding motions. If such wear increases, the operation of the vertical sealing device 54 becomes unstable, which may cause sealing failure or mechanical vibration, and may shorten the time for replacement of the vertical sealing device 54 .

In order to reduce the amount of offset between the pushing position of the piston rod 66 of the air cylinder device 64 and the seal center position of the vertical heater block 58, there is a method of using a dual rod cylinder device or a tandem cylinder device as an air drive cylinder device. . That is, since the offset amount D2 is related to the size of the cylinder diameter, in order to secure the required air pressure receiving area while suppressing the cylinder diameter, a dual rod cylinder device in which two small cylinder diameters are arranged in parallel is used, or It is conceivable to use a tandem cylinder device in which two cylinders with small diameters are arranged in series. The offset amount in this case can be suppressed to a small value corresponding to a small cylinder diameter. However, both types of devices are expensive air cylinder devices, and it is unavoidable that the cost of replacement when the air cylinder device wears out becomes high.

Japanese Unexamined Patent Application Publication No. 2012-1211

Therefore, in the vertical sealing device in the vertical form-fill-sealing machine, even if the air cylinder device for driving the vertical heater block of the vertical sealing device is arranged at a position offset from the vertical heater block to the front side of the front side, the air cylinder The device has a problem to be solved in terms of applying a driving force in the sliding direction to the movable vertical heater block with as little moment as possible.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, and the structure is devised so that the driving device applies a driving force in the sliding direction to the vertical heater block on the movable side with as little moment as possible. As a result, uniform pressure is generated on the heat sealing surface of the vertical heater block on the movable side without relying on an expensive driving device, thereby preventing partial weakening of the sealing pressure and reducing wear at the sliding portion. To provide a vertical sealing device in a vertical form-fill-seal packaging machine capable of preventing the occurrence, stabilizing the operation of the vertical sealing device, and avoiding defective sealing and mechanical vibration.

In order to solve the above-mentioned problems, the vertical sealing device in the vertical form-fill-sealing machine according to the present invention includes a vertical preheating heater block having a vertical preheating heater surface and a vertical preheating heater block that can move forward and backward relative to the vertical preheating heater block. a vertical heater block guided along a slide axis and provided with a vertical heater surface facing the vertical preheating heater surface; and an air cylinder device for driving the vertical heater block along the slide axis. and a link mechanism for transmitting the output of the air cylinder device to the vertical heater block such that the vertical heater block advances and retreats toward the vertical preheating heater block. and the link member at the end of connection of the link mechanism is rotatably connected via a connecting pin to the rear surface of the vertical heater block opposite to the side on which the vertical heater surface is provided. consists of

According to the vertical sealing device in this vertical form-fill-sealing machine, the output of the air cylinder device is transmitted to the vertical heater block by a link mechanism composed of a plurality of linked link members. The last link member connected to the vertical heater block of the link mechanism is directly rotatably connected via the connecting pin on the rear surface of the vertical heater block. is pushed directly, and no moment is transmitted to the vertical heater block from the beginning. In addition, since the pressing force acts directly on the vertical heater block, the amount of offset between the line of action of the pressing force by the connecting pin and the center line of the seal on the heater surface of the vertical heater block can be minimized. Therefore, the moment generated in the vertical heater block due to the offset amount is naturally reduced. The moment acting on the vertical heater block generally generates uneven surface pressure that twists the slide shaft against the peripheral surface of the slide shaft when the vertical heater block is slid and guided along the slide shaft, resulting in frictional resistance. However, according to the vertical sealing device of the present invention, even if such a moment occurs, it does not become a large moment, so the sealing pressure does not become uneven, and the vertical heater The block is slidably guided along the slide axis.

In the vertical sealing device in this vertical form-fill-sealing machine, the path of force transmitted from the air cylinder device to the vertical heater block through the link mechanism includes the output axis of the air cylinder device and the vertical heater block. It may be contained within one force transmission plane perpendicular to the longitudinally extending longitudinal axis of the block.
By arranging the path of the force transmitted from the air cylinder device to the vertical heater block in such a single force transmission plane, the output of the air cylinder device is twisted to the vertical heater block. It can be transmitted simply and efficiently as a pushing force without creating an excessive moment. Also, in the vertical form-fill-seal packaging machine, the arrangement of the air cylinder device and the link mechanism can be simplified.

In the vertical sealing device in this vertical form-fill-sealing machine, the link mechanism includes a connecting portion between the air cylinder device and the vertical heater block, and a plurality of connecting members for rotatingly connecting two connecting members to be connected. Each of the connecting pin structures has a bifurcated structure in which one connecting member sandwiches the other connecting member, and either the one connecting member or the other connecting member A connecting pin fixed to the other connecting member is rotatably supported via a bearing with respect to the remaining connecting member, and the resulting force acting axis of the bifurcated structure of the one connecting member and the other connecting member The force application axes may all be contained within the force transmission plane.
The link mechanism is connected by a connecting pin structure including such a bifurcated structure, and the resultant force acting axis of the bifurcated structure of one connecting member and the force acting axis of the other connecting member are both in one force transmission plane. , the line of action of force is kept in one force transmission plane, and wasteful bending and twisting from the air cylinder device and finally to the vertical heater block are avoided. Since the generation of moment is suppressed, the output of the air cylinder device can be efficiently transmitted to the vertical heater block as a pushing force.

In the vertical sealing device in this vertical form-fill-sealing machine, the connecting pin and the bearing, which constitute the connecting pin structure between the back surface of the vertical heater block and the link member at the end of the connection, are arranged such that the connecting pin A flat surface is formed by notching a part of the connecting pin, and the connecting pin is fixedly attached to the vertical heater block on the flat surface. It can be rotatably supported by the intermediate portion via the bearing.
The connection pin is fixedly attached to the vertical heater block by the flat surfaces formed on both ends thereof, and the last link member connected to the connection pin is rotatably supported by the central round shaft portion of the connection pin via a bearing. Then, the link member at the end of the connection can be directly attached to the rear surface of the vertical heater block without leaving a distance therebetween, and the two can be rotatably connected.

In the vertical sealing device in this vertical form-fill-sealing machine, the link member at the end of connection that pushes the vertical heater block may extend in a direction substantially along the axial direction of the slide shaft. .
The link member at the end of connection extends substantially parallel to the axial direction of the slide shaft in its longitudinal direction and is rotatably connected directly to the back surface of the vertical heater block via the connection pin. The force of the link member to push the back surface of the vertical heater block is substantially only in the axial direction of the slide shaft (that is, the advancing and retreating direction of the vertical seal bar). In the force acting on the link member at the end of the connection, the component in the direction orthogonal to the axis of the slide shaft is substantially zero, and the output of the air cylinder device is efficiently transmitted to the heat seal surface. It is possible to minimize the occurrence of moment that twists the slide shaft against the block.

In the vertical sealing device in this vertical form-fill-sealing machine, the link mechanism includes a main link rotatable with respect to the machine frame by means of one connecting pin structure, and one end of the main link is connected to the output member of the air cylinder device via the other connecting pin structure in the above, and the last link of the connection via the other connecting pin structure at the other end of the main link the members are connected such that the circumferential movement of the other end as the main link rotates relative to the machine frame is substantially along the slide axis; can be
When the main link of the link mechanism rotates with respect to the machine frame by the output of the air cylinder device, the circumferential movement of the other end portion is substantially parallel to the slide shaft. Therefore, the link member at the end of the connection extends in a direction substantially along the axial direction of the slide shaft structurally, and in terms of force transmission, it extends substantially in its longitudinal direction, i.e., in the axial direction of the slide shaft. , and the link member does not transmit substantially any moment to the vertical heater block, but transmits only the pushing force.

In the vertical sealing device in this vertical form-fill-sealing machine, any one of One of the connecting pin structures may be a connecting structure in which play between the connecting pin and the bearing and play in the axial direction of the connecting pin are provided.
By making any one of the connecting pin structures a connecting structure with play, play in the vertical direction, which is the axial direction of the connecting pin, and in the lateral direction, which is the radial direction of the connecting pin, is absorbed. Therefore, it is possible to absorb machining errors and assembly errors of the link mechanism including the connecting portion between the air cylinder device and the vertical heater block, and smooth operation of the link mechanism.

The vertical sealing device in the vertical form-fill-seal packaging machine according to the present invention is constructed as described above, and the output of the air cylinder device is transmitted to the vertical heater block by a link mechanism comprising a plurality of linked link members. However, at that time, the last link member connected to the vertical heater block of the link mechanism is directly rotatably connected via the connecting pin on the back surface of the vertical heater block, so that the last link of the link mechanism is not affected by the moment is not transmitted to the vertical heater block, the rear surface of the vertical heater block is simply pushed directly. In addition, since the amount of offset between the line of action of the pressing force by the connecting pin and the seal center line of the heat sealing surface of the vertical heater block can be minimized, the moment generated in the vertical heater block due to the amount of offset can be minimized. will naturally become smaller. Therefore, the prying action of the vertical heater block on the slide shaft is minimized, the vertical heater block is stably slidably guided along the slide shaft, and the sealing pressure by the vertical heater block is made uniform, resulting in a vertical sealing device with stable operation. can provide. In addition, since the air cylinder device and the vertical heater block are connected by a link mechanism, the manufacturing cost is basically low, and the uneven wear of the slide structure fitted to the slide shaft is small, so the air cylinder device wears frequently. is lower and maintenance costs are lower.

FIG. 1 is a plan view showing an embodiment of a vertical sealing device in a vertical form-fill-seal machine according to the present invention. 2 is a schematic perspective view of the vertical sealing device shown in FIG. 1. FIG. 3 is a partially enlarged view of the vertical sealing device shown in FIG. 1. FIG. FIG. 4 is a perspective view showing an example of a conventional vertical form-fill-seal machine. FIG. 5 is a plan view showing an example of a vertical sealing device in a conventional vertical form-fill-seal machine. 6 is a schematic perspective view of the vertical sealing device shown in FIG. 5. FIG.

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a vertical sealing device in a vertical form-fill-seal packaging machine according to the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a plan view showing one embodiment of the vertical sealing device according to the present invention, and FIG. 2 is a schematic perspective view of the vertical sealing device shown in FIG.

The vertical sealing device 1 shown in FIG. 1 is, for example, a conventionally known vertical form-fill-fill-seal machine as shown in FIG. In a vertical bag-making, filling and packaging machine that manufactures a bag package in which a product filled through a bag-making and filling cylinder while forming a It can be applied as an apparatus for sealing both side edge portions and forming the belt-shaped packaging material into a tubular packaging material. The configuration of the vertical form-fill-seal packaging machine itself will not be described again here, and the reference numerals shown in FIG. 4 will be used when necessary for the description.

FIG. 1 shows a cross section of a part of the belt-like packaging material Fw that is bent into a substantially cylindrical shape around the bag-making, filling and packaging tube 52 of the vertical bag-making, filling and packaging machine 50 (FIG. 4). , the vertical sealing device 1 is arranged on the front side of the bag making and filling tube 52 . The belt-shaped packaging material Fw is bent into a substantially cylindrical shape by a former 51 of the bag-making, filling, and packaging machine 50 and surrounds the outer peripheral surface of the bag-making, filling, and packaging tube 52 . Both side edge portions fe, fe of the belt-shaped packaging material Fw are formed by bending the main body of the belt-shaped packaging material Fw, extend in a direction standing up from the outer peripheral surface of the bag-making and filling tube 52, and the sealable inner surfaces face each other. placed in a state. The vertical sealing device 1 sandwiches both side edge portions fe, fe, pressurizes and heats them, and welds the inner surfaces to each other to form a vertical seal Sc.

In the vertical sealing device 1 shown in FIGS. 1 and 2, the structure of the vertical heater blocks 2 and 3 themselves of the vertical sealing device 1 is such that the vertical direction is the longitudinal direction, similar to the structure of the conventional vertical heater blocks 57 and 58. It is a bar-shaped heater block that is in contact with each other, and has heater surfaces 2a and 3a that are opposed to each other at the ends thereof. The vertical heater block 2 is a vertical heater block on the fixed side, and the set temperature of the heater surface 2a is relatively low. notation) . The vertical heater block 3 is a vertical heater block on the movable side, which has a high set temperature of the heater surface 3a and can heat-seal the packaging material. Both heater blocks 2 and 3 move toward the vertical preheating heater block 2 and sandwich both side edge portions fe and fe between the heater surfaces 2a and 3a to apply pressure and heat. A vertical seal Sc is applied. Both heater blocks 2 and 3 have a known structure such as a heat pipe 4 on the tip side and a cartridge heater 5 in the central portion.

A vertical sealer arm 6 as a machine frame is provided on the front side of the bag making and filling tube 52 so as to be openable and closable. In the illustrated state, the vertical sealer arm 6 closes the front side of the bag-making and filling tube 52, but in the open state (not shown), the bag-making and filling tube 52 can be accessed from the front side. . The vertical sealer arm 6 includes a block-shaped arm body 6a, one support portion 7a and the other support portion 7b integrally extending from the arm body 6a toward the bag-making and filling tube 52, and a bag-making and filling device. and a support portion 7c integrally extending in a direction away from the cylinder 52. - 特許庁A connecting pin 23 is provided at the end of the arm body 6a of the vertical sealer arm 6 on the side of the support portion 7b so as to rotatably support the main link 21, which will be described later, and projects vertically from the main link 21. , and a bearing 8 which is provided on the bifurcated support portion 7b and supports the connecting pin 23 so as to be rotatable. As shown in FIG. 2, each of the support portions 7a to 7c is attached to the arm body 6a in a manner of a bracket (particularly, the support portion 7b is not a bifurcated structure but a single bracket separated laterally outwardly of the main link 21). aspect)) .

The vertical preheating heater block 2 on the fixed side is fixedly attached to the tip portion of one supporting portion 7a extending long from the arm main body 6a, and its position is immovable. A mounting hole 9a for mounting a horizontally extending slide shaft (round shaft) 10 is formed in the intermediate portion of the support portion 7a. A mounting hole 9b for mounting the slide shaft 10 is also formed. The slide shaft 10 is a shaft that guides the movement of the vertical heater block 3 on the movable side to move toward and away from the vertical preheating heater block 2 on the fixed side. The axes of the mounting hole 9a formed in the support portion 7a and the mounting hole 9b formed in the support portion 7b are aligned, and the slide shaft 10 is fitted in the mounting holes 9a and 9b at both ends thereof. fitted and attached.

A sleeve 11 (illustration of the sleeve 11 is omitted in FIG. 2) is slidably fitted to the outer peripheral surface of the slide shaft 10, and a mounting plate 12 to which the vertical heater block 3 on the movable side is mounted is attached to the sleeve 11. It is fixedly attached to the outer peripheral surface. Due to the structure using the sleeve 11, both the sleeve 11 and the mounting plate 12 of the vertical heater block 3 on the movable side are guided by a wide slide surface over a long range in the axial direction with respect to the slide shaft 10, and are supported so as to be smoothly slidable. It is The slide shaft 10 is a pair of shafts 10, 10 (see FIG. 2) that are vertically parallel, so that the vertical heater block 3 on the movable side can move horizontally without rotating around the slide shaft 10. supported so as to slide accurately and stably.

In the vertical sealer arm 6, the support portion 7c is provided on the side corresponding to the long support portion 7a. An air cylinder device 14 for operating the vertical seal device 1 is rotatably attached to the tip of the support portion 7c by a rotary connection portion 16. As shown in FIG. The rotary connecting portion 16 includes a connecting pin 17 attached to the cylinder 15 of the air cylinder device 14 and a bearing 18 provided at the bifurcated end portion of the support portion 7c to rotatably support the connecting pin 17. and The rotation axis of the connecting pin 17 is orthogonal to the slide shaft 10 and extends in a direction parallel to the longitudinal direction in which both bar-shaped heater blocks 2 and 3 extend.

A link mechanism 20 connects an output rod 19 as an output member that protrudes and retracts from the cylinder 15 when the air cylinder device 14 is operated, the vertical heater block 3 on the movable side, and the mounting plate 12 that supports it. The output rod 19 has a rod head 19a which is threaded to allow its length to be changed. The link mechanism 20 includes the main link 21 rotatably supported by the connecting pin structure 22 with respect to the vertical sealer arm 6, as described above. The main link 21 is shown in FIG. 1 as extending between the bifurcated portions of the support portion 7b. In FIG. 2, the main link 21 is shown extending through an opening 6b formed in the longitudinal sealer arm 6, the connecting pin structure 22 of the main link 21 extending from the longitudinal intermediate portion of the main link 21. A connecting pin 23 extending vertically is rotatably supported via a bearing 8 in each of the bifurcated portions formed by the opening 6 b of the arm body 6 a of the vertical sealer arm 6 .

One end of the main link 21 (the end on the air cylinder device 14 side) and the rod head 19a are rotatably supported via a connecting pin structure 24 . Like the connecting pin structure 22, the connecting pin structure 24 includes a connecting pin 25 extending vertically from the rod head 19a and one end of the main link 21 having a two-forked structure. is provided with a bearing 26 that rotatably supports the . Also for the other end of the main link 21 (the end on the vertical heater block 3 side), one end of the connecting last link member (hereinafter referred to as “push link”) 27 of the link mechanism 20 is connected to a connecting pin structure 28 . It is rotatably connected via. As with the connecting pin structures 22 and 24, the connecting pin structure 28 is provided at the other end of the main link 21, which has a bifurcated structure, and connects with the connecting pin 29 extending vertically on the push link 27. A bearing 30 is provided to rotatably support the pin 29 .

The mounting plate 12 side end of the push link 27 and the mounting plate 12 are rotatably connected by a connecting pin structure 32 . The connecting pin structure 32 includes a connecting pin 33 attached to the mounting plate 12 that supports the vertical heater block 3 and a bearing 34 that is provided at the end of the push link 27 and supports the connecting pin 33 rotatably. ing. By locating the connecting pin structure 32 as close as possible to the mounting plate 12 , when the push link 27 pushes against the mounting plate 12 and the vertical heater block 3 , there is no transmission that creates a moment on the mounting plate 12 . can be avoided. Therefore, as shown in FIG. 2, an opening 12a is formed in the mounting plate 12 to allow the connecting pin structure 32 to partially enter the opening 12a. The opening 12a may be formed as a notch or a recess as shown in FIG.

3 is an enlarged perspective view of the connecting pin structure 32. FIG. As shown in FIG. 3, the connecting pin 33 has upper and lower portions (both ends of the pin in the longitudinal direction) 33a and 33b partially processed into flat surfaces 33c and 33c. One of the flat surfaces 33c, 33c is fixedly attached to the back surface of the vertical heater block (specifically, the back surface of the mounting plate 12) with screws 35, 35 in a state of planar contact. A round shaft-shaped intermediate portion between the upper and lower portions 33 a and 33 b of the connecting pin 33 is rotatably supported by the push link 27 through a bearing 34 . By changing the arrangement of the connecting pin and the bearing, the connecting pin 33 is fixedly attached to the push link 27 side, and the upper and lower ends or the longitudinal middle portion of the connecting pin 33 are rotated by the bearing 34 on the back side of the vertical heater block 3. A movably attached structure may be used. The connecting pin structure 32 using such a connecting pin 33 allows the push link 27 to be rotatably connected directly to the back surface of the vertical heater block 3 (and thus the mounting plate 12) without leaving a distance. Instead of forming flat surfaces 33c, 33c on both sides of the upper and lower portions 33a, 33b of the connecting pin 33, they are cut into a half-moon shape, and one of the flat surfaces is fixed to the mounting plate 12 in contact with the rear surface. good too. In this case, the axis of the connecting pin 33 can be located on the rear surface of the mounting plate 12 to avoid a moment-generating transmission when the push link 27 transmits the pushing force through the connecting pin structure 32. can be done.

In the embodiment of the vertical sealing device 1 configured as described above, the position of the intermediate portion of the main link 21 of the link mechanism 20 is pinned to the arm body 6a of the vertical sealer arm 6 by the connecting pin structure 22, The heater block 3 is in a state where the sliding direction is regulated by the slide shafts 10,10. Under these conditions, when the air cylinder device 14 operates, the cylinder 15 can be rotated by the connecting pin 17 and the bearing 18, and the air cylinder device 14 and the main link 21 are slightly moved by the connecting pin structures 22 and 24, respectively. to rotate. Strictly speaking, the push link 27 is also rotated by the connecting pin structure 28. During this rotation, the longitudinal direction of the push link 27 is substantially parallel to the axial direction of the slide shafts 10, 10, and the main link 21 is rotated. Circumferential movement of the other end portion is also substantially parallel to the axial direction of the slide shafts 10, 10, so that ultimately the push link 27 is substantially parallel to its longitudinal direction and to the slide shafts 10, 10. 10, so that only the pushing force F in the direction parallel to the axial direction of the slide shafts 10, 10 (that is, the advancing and retreating direction of the vertical seal block 3) is applied to the back surface of the vertical heater block 3. to act on The force component applied by the push link 27 in the direction orthogonal to the axes of the slide shafts 10, 10 is substantially zero, and the output of the air cylinder device 14 is efficiently transmitted to the heater surface 3a. , it is possible to suppress the occurrence of a moment that twists the slide shafts 10, 10 to the vertical heater block 3 as much as possible.

Since the push link 27 of the link mechanism 20 is directly rotatably connected to the back surface of the vertical heater block 3 via the connecting pin structure 32, the back surface of the vertical heater block 3 is simply pushed directly with the pushing force F. No moment is transmitted to the vertical heater block 3 from the beginning. Also, the line of action L1 of the pressing force F by the connecting pin structure 28 and the line of action L2 of the seal centers of the heater surfaces 2a and 3a of the heater blocks 2 and 3 are offset D1 (L1, L2 and D1 are shown in FIGS. 1 and 3) . 2) can be made as small as possible. Therefore, the moments M1 and M1 (see FIG. 2) generated in both heater blocks 2 and 3 due to the offset amount D1 are naturally reduced, and the sealing pressures on the heater surfaces 2a and 3a become substantially uniform. When the moment M1 generated in the vertical heater block 3 becomes a large value, generally, when the vertical heater block 3 is slidably guided along the slide shafts 10, 10, the peripheral surfaces of the slide shafts 10, 10 are twisted. A uniform surface pressure is generated, which causes an increase in frictional resistance or an uneven wear. The vertical heater block 3 is slidably guided along the slide shafts 10,10.

The path of force transmitted from the air cylinder device 14 to the vertical heater block 3 through the link mechanism 20 is the longitudinal direction of the vertical heater block 3 including the axis of the output rod 19, which is the output member of the air cylinder device 14. It is contained within one force transmission plane S (see FIG. 2) perpendicular to the axis. In addition, in FIG. 3, the intersecting line when this force transmission plane S intersects with the vertical sealing device 1 is indicated by a one-dot chain line CL. The axis of the main link 21 of the linkage 20 and the axis of the push link 27 are also in this force transmission plane S. By arranging the path of the force transmitted from the air cylinder device 14 to the vertical heater block 3 so as to be within such a single force transmission plane S, the output of the air cylinder device 14 is applied to the vertical heater block 3 as follows: Therefore, the pushing force F can be transmitted simply and efficiently without generating a moment of bending or twisting. Also, in the vertical form-fill-seal packaging machine 50, the arrangement of the air cylinder device 14 and the link mechanism 20 can be simplified.

The link mechanism 20 includes a plurality of rotatable connecting pin structures 22 , 24 , 28 including the connecting portion between the air cylinder device 14 and the vertical heater block 3 . The connecting pin structures 22, 24, and 28 are, as shown in the perspective view of FIG. It has a bifurcated structure in which one connecting member sandwiches the other connecting member, and a connecting pin fixed to either the one connecting member or the other connecting member rotates with respect to the remaining connecting member via a bearing. supported as possible. Therefore, in the connecting pin structures 22, 24, 28, both the resultant force acting axis of the bifurcated structure of one connecting member and the force acting axis of the other connecting member are included in the force transmission plane S described above. By configuring the connecting pin structures 22, 24, 28 in this way, the line of force action is kept within a single force transmission plane S and is not offset, so that ultimately the vertical heater block 3 does not bend or bend. It is possible to suppress the occurrence of useless torsional moment.

In order to absorb processing errors and assembly errors of the link mechanism 20 including the connecting portion between the air cylinder device 14 and the vertical heater block 3, any one of the connecting pin structures 22, 24, 28 is used as a connecting pin. It is possible to provide a connecting structure in which play between the bearings and axial play of the connecting pin is provided. By making any one of the connecting pin structures 22, 24, and 28 a connecting structure with play, the vertical direction, which is the axial direction of the connecting pin, and the horizontal direction of two orthogonal axes, which is the radial direction of the connecting pin The play in the direction is absorbed, the vertical heater block 3 does not generate a moment, and its operation can be smoothed. In this example, for example, the connecting pin structure 28 can be preliminarily provided with backlash in order to absorb machining errors and assembly errors of each part.

The vertical form-fill-sealing machine 50 has been described as an intermittent-acting form-filling-sealing machine. By operating it, a continuous operation type form-fill-seal-packaging machine can be obtained. Further, the above vertical sealing device 1 has been described assuming that the vertical preheating heater block 2 is fixed and the vertical heater block 3 is movable. Heat sealing may be performed by sandwiching the edge portions fe, fe from both sides. The air cylinder device 14 and the link mechanism 20 of the vertical sealing device 1 described above can be applied as they are to the opening/closing operation of the vertical sealing device of the continuous operation type form-fill-seal machine. In the description of the embodiment, the vertical heater block 3 is attached to the mounting plate 12. However, since the vertical heater block 3 and the mounting plate 12 are integrally fixed to each other, conceptually, the heater block cannot be attached to the heater block. may be included.

REFERENCE SIGNS LIST 1 vertical sealing device 2 vertical preheating heater block 2a heater surface 3 vertical heater block 3a heater surface 4 heat pipe 5 cartridge heater 6 vertical sealer arm 6a arm body 6b opening 7a, 7b, 7c support 8 bearing 9a, 9b mounting hole 10 Slide shaft 11 Sleeve 12 Mounting plate 12a Opening 14 Air cylinder device 15 Cylinder 16 Rotation connecting part 17 Connecting pin 18 Bearing 19 Output rod 19a Rod head 20 Link mechanism 21 Main link 22 Connecting pin structure 23 Connecting pin 24 Connecting pin Structure 25 Connecting pin 26 Bearing 27 Push link 28 Connecting pin structure 29 Connecting pin 30 Bearing 32 Connecting pin structure 33 Connecting pins 33a, 33b Upper and lower parts 33c, 33c Flat surface 34 Bearings 35, 35 Screw 50 Vertical form-fill-seal machine 51 cylinder making device 52 bag making and filling cylinder 54 vertical sealing device 53a, 53b paper feed belt 55 horizontal sealing device 56a, 56b horizontal heater block 57 vertical preheating heater block 58 vertical heater block 57a, 58a heater surface 59, 59 brackets 60, 60 Slide shaft 61 Sleeve 62 Mounting plate 63 Vertical sealer arm 64 Air cylinder device 65 Cylinder 66 Piston rod Fw Belt-shaped packaging material fe, fe Side edge portion Ft Cylindrical packaging material Sc Vertical seal Se Horizontal seal L1 Line of action of pushing force F L2 Seal Center line of action L3 Driving force line of action L4 Seal center line of action D1, D2 Offset amount (distance)
F Push force M1, M2 Moment S Force transmission plane CL Intersection line

Claims (7)

a vertical preheater block having a vertical preheater surface;
a vertical heater block guided along a slide shaft so as to be able to move forward and backward relative to the vertical preheating heater block and having a vertical heater surface facing the vertical preheating heater surface;
An air cylinder device for driving the vertical heater block along the slide shaft, and a plurality of linked link members . a link mechanism for transmitting the heater block to advance and retreat toward the vertical preheating heater block,
The link member at the end of connection of the link mechanism is rotatably connected via a connecting pin to the rear surface of the vertical heater block opposite to the side provided with the vertical heater surface;
A vertical seal device for a vertical form-fill-seal machine. The path of force transmitted from the air cylinder device to the vertical heater block through the link mechanism is one force that includes the output axis of the air cylinder device and is perpendicular to the longitudinal axis of the vertical heater block. 2. The vertical sealing device of a vertical form-fill-seal machine according to claim 1, wherein the vertical sealing device is contained within the transmission plane. The link mechanism includes a plurality of connecting pin structures for rotationally connecting two connecting members to be connected, including the connecting portion between the air cylinder device and the vertical heater block,
Each of the connecting pin structures has a bifurcated structure in which one connecting member sandwiches the other connecting member, and the connecting pin fixed to either the one connecting member or the other connecting member remains. One connecting member is rotatably supported via a bearing, and the resultant force acting axis of the bifurcated structure of the one connecting member and the force acting axis of the other connecting member are both the 3. The vertical sealing device of a vertical form-fill-seal machine according to claim 2, wherein the vertical sealing device is contained within a force transmission plane. With respect to the connecting pin and the bearing, which constitute the connecting pin structure between the back surface of the vertical heater block and the last connecting link member, a part of the connecting pin is notched to form a flat surface, and the connecting a pin fixedly attached to the longitudinal heater block at the flat surface;
4. The vertical form-fill-seal machine according to claim 3, wherein said link member at the end of connection is rotatably supported by said shaft-shaped intermediate portion of said connecting pin via said bearing. vertical sealing device. 5. The vertical sealing device for a vertical form-fill-seal packaging machine according to claim 4, wherein said last connecting link member for pressing said vertical heater block extends in a direction substantially along the axial direction of said slide shaft. . The link mechanism includes a main link that is rotatable with respect to the machine frame by one of the connecting pin structures, and one end of the main link is connected to the air cylinder through another of the connecting pin structures. connected to the output member of the device and connected to the last link member at the other end of the main link via a further connecting pin structure;
6. The apparatus of claim 5, wherein the circumferential movement of said other end as said main link pivots relative to said machine frame is movement in a direction substantially along said slide axis. The vertical seal device of the vertical form-fill-seal machine. In order to be able to absorb machining errors and assembly errors of the link mechanism including the connecting portion between the air cylinder device and the vertical heater block, any one of the connecting pin structures may be used between the connecting pin and the bearing. 7. The vertical sealing device for a vertical form-fill-sealing machine according to claim 3, wherein the connecting structure is such that play between the connecting pins and play in the axial direction of the connecting pin are provided.

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