JP2016210474A - Packaging device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a packaging device, simply structured, which can package a packaging material into an object to be packaged highly-efficiently.SOLUTION: The packaging device comprises: a caterpillar track which can be partially opened and closed and comprises a plurality of sprockets which are respectively arranged at predetermined pitch and can be turned; a shuttle which comprises a driven chain to which is transmitted thrust from the sprockets and can circle on the caterpillar track; a packaging material supply device which is mounted on the shuttle and holds a packaging material to be pulled out accompanying the circling of the shuttle; and a support device which supports an object to be packaged, at least part of which is surrounded around the caterpillar track.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a packaging device for packaging an article to be packaged with a packaging material, and more specifically to a packaging device for winding a stretchable film around a wire coil or a rolled steel plate.

  As an apparatus for packaging an annular packaging object, for example, a coil of a metal linear body or a metal strip, for example, a packaging apparatus disclosed in Patent Document 1 below is known. In this packaging apparatus, it has a loop body composed of two beams and a gate portion that can be opened and closed with respect to these beams, and the shuttle is arranged so as to be able to circulate along the inner peripheral surface of the loop body. . The shuttle is self-propelled by an electric motor and contains a roll-wrapped packaging material.

  In the operation of such a device, the gate part of the loop body is opened, the steel strip coil is set in the loop body so that the beam of the loop body penetrates the hole of the steel strip coil to be wrapped, and the gate part is closed. Next, the packaging material is pulled out from the inside of the shuttle, and the tip is fastened to the steel strip coil. Then, the packaging material from the inside of the shuttle can be wound around the band steel coil by moving the shuttle along the loop body while rotating the band steel coil.

Further, there is Patent Document 2 shown below as a packaging device that can package a relatively large object to be packaged but can be made compact with a simple configuration. According to this Patent Document 2, there is a configuration in which a part of an annular track is configured to be openable and closable, a cart is mounted on the annular track, and packaging material supply means is mounted on the cart to supply packaging material from a packaging material coil. It is disclosed.
In the operation of such a device, a part of an object to be packaged is placed in a closed annular track and supported by support means, and a cart driving means is provided along the annular track to drive the cart driving means in cooperation with the cart. By doing so, the carriage is circulated along the annular track.

Further, Patent Document 3 below is known as a packaging apparatus that supplies a packaging material by means of a packaging material supply means that is fixed separately from a moving body that moves along an annular guide body. According to Patent Document 3, an object to be packaged is arranged in an inner space of an annular guide body, and the moving body is annularly guided by the moving body drive means in a state where the packaging material from the packaging material supply means is attached to the object to be packaged. Move along the body. Accordingly, the moving body moves around the packaged object while entraining the packaged material extending between the packaged object and the packaging material supply means, thereby packaging the packaged object with the packaging material.
According to such a packaging apparatus, even when the packaging material supply source of the packaging material supply means arranged outside the annular guide body is enlarged, the moving body that moves along the annular guide body due to this is the annular guide body. It will not interfere with the object to be packaged placed in the interior space.

Japanese Patent Laid-Open No. 5-294314 Japanese Patent Laid-Open No. 11-22707 WO2000 / 044623

However, the above-described conventional packaging apparatuses still have problems to be solved.
That is, for example, in the packaging device disclosed in Patent Literature 1, it is necessary to go around the inner space of the loop body, which is a limited space, but it is difficult to say that the structure and operation are efficient.

Further, in the packaging device disclosed in Patent Document 2, since the toothed belt as the cart driving means is installed over the entire inner peripheral surface of the annular track, the driving mechanism for driving the cart is inevitably complicated. turn into.
On the other hand, in the packaging apparatus disclosed in Patent Document 3, since the steel sheet roll is packaged by fixing the film body and driving the film roller chain with the driving device, the mechanism for feeding the film becomes slightly complicated. At the same time, it is not always efficient because the film is wasted or wrinkled during packaging.
The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a packaging device that has a simple structure and that can package a packaging material on a package with high efficiency.

  In order to solve the above-described problems, a packaging apparatus according to an embodiment of the present invention includes (1) a plurality of sprockets that can be opened and closed at least partially and are arranged and rotated at a predetermined pitch. An endless track and a driven chain to which thrust is transmitted from the sprocket are provided, and a shuttle that can circulate on the endless track, and a packaging material that is mounted on the shuttle and pulled out with the rotation of the shuttle are held. A packaging material supply device and a support device for supporting an object to be packaged at least partially surrounded by the endless track.

  In the packaging device of the above (1), (2) the driven chain is arranged on a first curve and is linked to the sprocket, and a second curve different from the first curve. It is preferable to include a second driven chain that is disposed at a position interlocked with the sprocket.

  In the packaging device of (2), (3) the endless track has a straight portion and a curved portion, and the plurality of sprockets are arranged on the straight portion and are connected to the first driven chain. It is preferable to include a corresponding first sprocket and a second sprocket disposed on the curved portion and corresponding to the second driven chain.

  According to the present invention, a lightweight shuttle that has a packaging material and does not have a built-in power source orbits an endless track, so that the packaging material can be packaged quickly and accurately even in a simple structure. Is possible.

It is a schematic front view which shows the packaging apparatus 1 concerning embodiment of this invention. It is a schematic side view which shows the packaging apparatus 1 concerning embodiment of this invention. It is the whole schematic figure (sectional drawing) of the shuttle 3 and the packaging material supply apparatus 4 among the packaging apparatuses 1 concerning embodiment of this invention. 1 is an overall schematic view (top view) of a shuttle 3 and a packaging material supply device 4 in a packaging device 1 according to an embodiment of the present invention. It is the schematic (top view) of the shuttle 3 concerning embodiment of this invention. It is the schematic (sectional drawing) of the shuttle 3 concerning embodiment of this invention. It is the schematic (sectional drawing) of the shuttle 3 concerning embodiment of this invention. FIG. 3 is a schematic view of the packaging material supply device 4 according to the embodiment of the present invention, and is a cross-sectional view of a nip roll portion 42. It is the schematic of the packaging material supply apparatus 4 concerning embodiment of this invention, and is a top view of the nip roll part 42. FIG. It is a figure which shows the detailed structure in the linear part D among the endless tracks 2 concerning embodiment of this invention. It is a figure which shows the detailed structure in the curve part C among the endless tracks 2 concerning embodiment of this invention. It is a schematic block diagram of the endless track 2 concerning embodiment of this invention. It is the perspective view which looked at the endless track 2 and the shuttle 3 concerning embodiment of this invention from the downward direction.

  Hereinafter, an embodiment for carrying out the present invention will be described. For convenience of explanation, the X direction, the Y direction, and the Z direction are defined as appropriate in the following description, but the scope of rights of the present invention is not intentionally limited or reduced. In addition, about structures other than the characteristic structure demonstrated in detail below, you may refer to the structure used with other well-known packaging apparatuses, such as patent document 1 thru | or 3 mentioned above, for example.

<Embodiment>
<Configuration of packaging device 1>
FIG. 1 is a schematic front view showing a packaging device 1 according to an embodiment of the present invention, and FIG. 2 is a schematic side view showing the packaging device 1.
As apparent from FIGS. 1 and 2, the packaging device 1 according to this embodiment includes an endless track 2 that can be opened and closed at least in part, a shuttle 3 that can circulate on the endless track 2, and the shuttle 3. A packaging material supply device 4 that is mounted and holds the packaging material L and a support device 5 that supports an article S to be packaged that is packaged by the packaging material L are provided.
In FIG. 1, for convenience of explanation, a total of seven shuttles 3 are depicted, but the present invention is not limited to this, and at least one shuttle 3 (and packaging material supply device 4) may circulate on the endless track 2. That's fine.

Although there is no restriction | limiting in particular in the to-be packaged object S used by this embodiment, For example, wire rods, such as a steel plate wound in the above-mentioned roll shape, a bundle of metal wires, are mentioned as a suitable packaged object S. In addition, the packaging apparatus as used in this embodiment says the apparatus for winding the to-be-packaged object S with a film or paper material, and is a concept also including the bundling apparatus for bundling the to-be-packaged object S.
The packaging material L can be applied in various ways as long as it is a material for restraining the above-described packaged object S, and examples thereof include a known stretch resin film and elastically deformable paper material for restraint purposes.

The endless track 2 is a metal structure and has an annular track that forms a closed path. The endless track 2 is provided with various members (such as a plurality of sprockets 21 that can be arranged and rotated at predetermined pitches described later) that are arranged along the annular track and drive the shuttle 3. .
The shuttle 3 is a structure that can circulate on the endless track 2, and is formed of, for example, a general structural rolled steel (SS400 or the like) or a metal such as aluminum. The shuttle 3 is provided with a driven chain 33 to which a thrust from a drive unit installed in the endless track 2 is transmitted.

The packaging material supply device 4 is mounted on the shuttle 3, supports the packaging material L described above, and can draw out the packaging material L as the shuttle 3 rotates.
The support device 5 is a structure including a first support portion 51 that supports the endless track 2 and a second support portion 52 that rotatably supports the article S to be packaged, and is made of a metal such as steel. Has been. Further, the support device 5 is equipped with a control device 53 (not shown) for driving a drive chain 22, an opening / closing mechanism 23, an article support part 52, and the like which will be described later. Then, the operator drives and controls the drive chain 22, the opening / closing mechanism 23, and the package support unit 52 by operating a touch panel type display unit provided in the control device 53 (details will be described later).
In addition, as illustrated in FIG. 2, the packaging device 1 of the present embodiment may further include a clamping device 60 that can clamp at least a part of the packaging material L. The clamp device 60 can move back and forth in the Y direction. And in the case of the packaging operation mentioned later, the 1st clamp position (refer to Drawing 2) where the clamp part which clamps packaging material L among clamp devices 60 is located in endless track 2 about the Y direction, and the 1st clamp position It is possible to move between the second clamp position where the clamp part is separated from the endless track 2 and located in the −Y direction.

Next, the detailed structure of the shuttle 3 and the packaging material supply apparatus 4 according to the present embodiment will be described with reference to FIGS.
As shown in FIGS. 3 and 4, the shuttle 3 includes a base 31 and a driven chain 33 (33 a, 33 b) disposed in the base 31. Furthermore, the shuttle 3 can support the packaging material supply device 4 on the base 31.

The base 31 is made of, for example, a general structural rolled steel (SS400 or the like) or a metal such as aluminum, and the packaging material supply device 4 is fixed to the upper surface of the base 31 via a fastening member (not shown). A pair of driven chains 33 are installed on the lower surface of the base 31 via a chain mounter 32.
As shown in FIGS. 4A to 4C, the driven chain 33 is different from the first curved line R1 from the first driven chain 33a disposed on the first curved line R1 and interlocked with the first sprocket 21a. It includes a second driven chain 33b disposed on the second curve R2 and interlocking with the second sprocket 21b.

  In the present embodiment, as will be described later, the first sprocket 21a is disposed on the straight line portion D of the endless track 2, so the first curve R1 shown in FIG. 4B is substantially a straight line. In addition, since the second sprocket 21b is disposed in the curved portion C of the endless track 2, the second curve R2 shown in FIG. 4C is a curve having a predetermined radius of curvature. Therefore, in the present embodiment, the first driven chain 33a has a linear outer shape, while the second driven chain 33b has a curved outer shape. As shown in FIGS. 4B and 4C, in this embodiment, the length of the first driven chain 33a in the X direction with respect to the traveling direction (X direction) of the shuttle 3 is the second driven chain. 33b is shorter than the length in the X direction.

  Further, the chain mounter 32 of the present embodiment has a shape corresponding to the driven chain 33. That is, the chain mounter 32 has a flat plate-shaped (first surface is flat) first chain mounter 32a on which the first driven chain 33a is mounted and a hook-shaped (surface convex toward the sprocket 21) on which the second driven chain 33b is mounted. And this surface is a curved surface corresponding to the aforementioned predetermined radius of curvature) and the second chain mounter 32b.

  As shown in FIG. 4A, in this embodiment, the length of the first chain mounter 32a in the X direction is the length of the second chain mounter 32b in the X direction with respect to the traveling direction (X direction) of the shuttle 3. It is shorter than that. As a result, the shuttle 3 can move in a straight line stably at the straight part D, and can be smoothly switched from the straight part D in the curved part C without backlash. The length of the first chain mounter 32a in the X direction may be the same as the length of the second chain mounter 32b in the X direction, or may be longer than the length of the second chain mounter 32b in the X direction. .

Next, the detailed structure of the packaging material supply apparatus 4 is demonstrated using FIG.3 and FIG.5.
The packaging material supply device 4 includes a packaging material support portion 41 that rotatably supports the packaging material L, and a nip roll portion that allows a part of the packaging material L to be pulled out while applying an appropriate tension to the packaging material L. 42 is comprised. In addition to the above, the packaging material supply device 4 may include a known configuration used in the above-described patent document and the like such as a guide roller, but the description thereof is omitted here.

  Further, as described above, the packaging material supply device 4 is fixed to the base 31 of the shuttle 3 via a fastening member or the like, and a part of the packaging material L is pulled out by the shuttle 3 moving on the endless track 2. The package S is packaged. As shown in FIG. 5, the nip roll portion 42 includes a connecting member 42 a that is connected to the rotation shaft of the packaging material support portion 41, and the posture of the nip roll portion 42 changes as the packaging material support portion 41 rotates. Is configured to do.

The endless track 2 and the packaging material supply device 4 on which the shuttle 3 is mounted are supported by a support device 5.
That is, as is apparent from FIGS. 1 and 2, the support device 5 includes a frame structure made of a metal such as a general structural rolled steel (SS400, etc.) or a carbon steel for mechanical structure (S45C, etc.), and has an endless track 2. The first support part 51 for supporting and the second support part 52 for supporting the article to be packaged S are configured.

The first support portion 51 fixes the endless track 2 at two locations below the endless track 2 via known fastening members such as screws. Moreover, the 2nd support part 52 is comprised including a pair of 1st roller 52a and the 2nd roller 52b which support the to-be-packaged product S rotatably.
In addition, an electric motor 54 is mounted in the support device 5, and the object to be packaged is rotated during the packaging operation by rotating the object support portion 52 via the electric motor 54 under the control of the control device 53 described above. S is sequentially rotated to enable appropriate wrapping. The electric motor 54 is connected to a commercial power source (not shown) so that electric power is appropriately supplied.

Next, the detailed structure of the endless track 2 according to the present embodiment will be described with reference to FIGS. 6 shows a partial perspective view in the straight line portion D of the endless track 2, and FIG. 7 shows a partial perspective view in the curved portion C.
As is apparent from the drawings, the endless track 2 of the present embodiment includes a frame 20 as a structural housing, a plurality of sprockets 21 that are grounded so as to be able to rotate within the frame 20, a drive chain 22 for rotating the sprocket 21, An opening / closing mechanism 23 for opening and closing a part of the endless track 2 and an electric motor 24 for driving the drive chain 22 are included.

The frame 20 is made of, for example, a metal such as a general structural rolled steel (SS400 or the like) or a mechanical structural carbon steel (S45C or the like), and a plurality of sprockets 21 and a drive chain 22 are installed on the inner peripheral side thereof. .
The sprocket 21 is manufactured, for example, by pressing or cutting a metal such as a general structural rolled steel (SS400 or the like) or a mechanical structural carbon steel (S45C or the like), and is installed in the straight portion D as described above. The first sprocket 21a (FIG. 6) and the second sprocket 21b (FIG. 7) disposed in the curved portion C are configured.

A plurality of drive chains 22 are provided along the X direction, and are staggered along the closed path of the endless track 2 (the start end of one drive chain 22 and a part of the end of the other drive chain 22 are Y Arranged so as to overlap each other in terms of direction). The drive chain 22 can rotate the sprocket 21 by receiving power from the electric motor 24 (see FIG. 1). As shown in FIG. 6 and FIG. 7, the drive chain 22 meshes with a pair of drive sprockets 25, and the sprocket 21 that is coaxially integrated with the drive sprocket 25 is rotated by the drive of the drive chain 22. It is a mechanism.
The electric motor 24 is also connected to the above-described commercial power source so that electric power is appropriately supplied.

  The opening / closing mechanism 23 opens and closes a part of the endless track 2 via an electric motor (not shown) with the opening end E (see FIG. 1) as a boundary when the article S is attached to or detached from the endless track 2. It is a mechanism to make. This electric motor is also connected to the commercial power source described above. The opening / closing mechanism 23 may open / close a part of the endless track 2 without using an electric motor.

In the present embodiment, the position of the first sprocket 21a arranged on the first curve R1 in the Y direction (hereinafter also referred to as “first arrangement form”) is the second sprocket arranged on the second curve R2. 21b is different from the position in the Y direction (hereinafter also referred to as “second arrangement form”).
More specifically, as shown in FIG. 8, in the curved portion C, the second sprocket 21b is arranged in the second arrangement form as shown by the AA cross section, the BB cross section, and the CC cross section. Yes. On the other hand, in the straight part D, the first sprocket 21a is arranged in the first arrangement form as shown in the DD cross section and the EE cross section.

As an example, FIG. 9 shows a perspective view of the shuttle 3 on the endless track 2 at the curved portion C as viewed from below.
In the curved portion C, the first driven chain 33a on the shuttle 3 side is not meshed with the sprocket 21 and is in a free state. On the other hand, the second sprocket 21b and the second driven chain 33b, which rotate when the drive chain 22 is driven, are engaged with each other, so that the shuttle 3 can circulate on the endless track 2 by obtaining thrust in the traveling direction. ing.

In the present embodiment, the distance P2 (see FIG. 4C) between the adjacent second sprockets 21b is shorter than the length in the traveling direction (X direction) of the second driven chain 33b. Therefore, the propulsive force is transmitted through the second sprocket 21b without interruption when the shuttle 3 orbits the endless track 2.
Also in the straight part D, the distance P1 between the adjacent first sprockets 21a (see FIG. 4B) is shorter than the length in the traveling direction (X direction) of the first driven chain 33a. Therefore, when the shuttle 3 orbits the endless track 2, the propulsive force is transmitted through the first sprocket 21a without interruption even in the straight portion D.

<Packaging operation>
Below, an example of the packaging operation | movement using the packaging apparatus 1 of this embodiment mentioned above is demonstrated.
When the packaging material L is used to wrap the article to be packaged S, first, the operator uses the control device 53 to drive the opening / closing mechanism 23 to open / close a part of the endless track 2.
Then, with the open end E opened and closed, for example, an object to be packaged S (such as the wire coil described above) placed on a cart (not shown) is placed on the object to be packaged support 52. At this time, at least a part of the article to be packaged S is inserted inside the endless track 2 (see FIG. 6 and the like).

After the article to be packaged S is placed on the article to be packaged support 52, the closing path is formed by closing a part of the endless track 2 that is in the open state by the opening / closing mechanism.
On the other hand, a packaging material L for packaging the article to be packaged S is installed on the packaging material support shaft 41 of the packaging material supply device 4 fixed to the shuttle 3. Various methods can be applied as the method of installing the packaging material L. For example, the packaging material L may be installed using a transport machine such as a forklift or a crane, or the packaging material L is manually attached to the packaging material support shaft 41. May be installed.

After the packaging material L and the packaging material S are installed, a part of the packaging material L is pulled out as an initial setting, and the packaging material L is wrapped using the packaging material L.
More specifically, for example, the drawing operation is performed by one of the following methods.
That is, the operation is first performed in the following order as the first packaging operation.
<First packaging operation>
First, a part of the packaging material L is pulled out by a machine or manually, and passes through a tension adjusting mechanism (not shown) and a packaging material cutting mechanism in the packaging material supply apparatus 4 described above to reach the nip roll portion 42. Further, a part of the packaging material L is pulled out from the nip roll portion 42 and fixed to the article S to be packaged. The fixing method is not particularly limited. For example, the packaging material L may be wound around the packaged object S only once, or temporarily fixed using a known temporary fastening part such as a pin. A part of the packaging material L may be fixed to the packaged object S.

Subsequently, the operator drives the electric motor 24 by the control device 53 and transmits the power to the drive chain 22. Then, as the drive chain 22 is driven, the plurality of sprockets 21 (the first sprocket 21a and the second sprocket 21b) arranged in the endless track 2 each start rotating.
Then, the shuttle 3 including the driven chain 33 that meshes with the rotating sprocket 21 starts rotating around the endless track 2. In the present embodiment, since the second driven chain 33b is bent in the curved portion C in the same manner as the radius of curvature of the curved portion C, the thrust from the sprocket 21b is transmitted to the second driven chain 33b with high efficiency.

Then, as the shuttle 3 continues to move on the endless track 2, the packaging material L supplied from the packaging material supply device 4 is wrapped around the packaging material S, and the packaging material S is wrapped.
The control device 53 appropriately controls the second support 52 to be driven via the electric motor 54 while the shuttle 3 is performing the above-mentioned circulatory movement, thereby rotating the package S in the Xθ direction. . This control may be visually operated by an operator, or may be automatically performed by the control device 53 by programming in advance.

After the shuttle 3 circulates on the endless track 2 a predetermined number of times and the article to be packaged S is sufficiently packaged, the packaging material L is cut by the packaging material cutting mechanism described above.
With the above operation, the packaging material L supported by the packaging material supply device 4 is efficiently packaged with respect to the article to be packaged S.

<Second packaging operation>
As the second method, the work is performed in the following order.
First, a part of the packaging material L (such as the start end) supported by the packaging material support shaft 41 is clamped by the clamping device 60 in the state of FIG. Next, the shuttle 3 is rotated on the endless track 2 by, for example, a half turn to a little less than one turn so that the packaging material L is in contact with the article to be packaged S while maintaining the state. Next, the clamping device 60 is retracted (moved in the −Y direction in FIG. 2) so that the clamping device 60 is not sandwiched between the article to be packaged S and the packaging material L.

After the clamp device 60 moves backward, the packaging material L is wrapped around the article to be packaged S by further rotating the shuttle 3 one or more times. Then, after the packaging material L is wound around the article to be packaged S, the clamp of the packaging material L is released by the clamp device 60.
Thereafter, the shuttle 3 circulates on the endless track 2 in accordance with the desired wrapping thickness, and the second support 52 is appropriately driven via the electric motor 54 as described above, so that the package S is moved in the Xθ direction. Rotation control is performed.

  Note that the above-described embodiment can be variously modified without departing from the spirit of the present invention. In the following, a modification of the embodiment will be described with reference to FIG. 11, but the description will mainly focus on differences from the above-described embodiments, and elements having the same configurations and functions as those described above will have the same reference numerals. The description and illustration are omitted as appropriate.

  As described above, the packaging device of the present invention is suitable for constructing a system having a simple structure and high packaging efficiency.

DESCRIPTION OF SYMBOLS 1 Packaging apparatus 2 Endless track 3 Shuttle 4 Packaging material supply apparatus 5 Support apparatus 20 Frame 21 Sprocket 22 Drive chain 23 Opening / closing mechanism 24 Electric motor 25 Driving sprocket 27 Key groove 31 Base 32 Chain mounter 33 Drive chain 41 Packaging material support shaft 42 Nip roll portion 51 First support portion 52 Second support portion 53 Control device 54 Electric motor 60 Clamp mechanism L Packaging material S Packaged object E Open end

In order to solve the above-described problems, a packaging apparatus according to an embodiment of the present invention includes (1) a plurality of sprockets that can be opened and closed at least partially and are arranged and rotated at a predetermined pitch. An endless track and a driven chain to which thrust is transmitted from the sprocket are provided, and a shuttle that can circulate on the endless track, and a packaging material that is mounted on the shuttle and pulled out with the rotation of the shuttle are held. A packaging material supply device; and a support device for supporting an object to be packaged at least partially surrounded by the endless track , wherein the driven chain is disposed on a first curve and interlocked with the sprocket. One driven chain and a second driven chain disposed on a second curve different from the first curve and interlocking with the sprocket are included .

In the packaging device of ( 1 ), ( 2 ) the endless track has a straight portion and a curved portion, and the plurality of sprockets are disposed on the straight portion and are connected to the first driven chain. It is preferable to include a corresponding first sprocket and a second sprocket disposed on the curved portion and corresponding to the second driven chain.

Claims (3)

An endless track comprising a plurality of sprockets that can be opened and closed at least in part, each arranged at a predetermined pitch and rotatable;
A shuttle including a driven chain to which thrust is transmitted from the sprocket, and a shuttle that can circulate on the endless track;
A packaging material supply device that is mounted on the shuttle and holds the packaging material that is pulled out as the shuttle circulates;
And a support device for supporting an object to be packaged at least partially surrounded by the endless track.   The driven chain includes a first driven chain disposed on a first curve and interlocked with the sprocket, and a second driven chain disposed on a second curve different from the first curve and interlocked with the sprocket. The packaging device according to claim 1. The endless track has a straight part and a curved part,
The plurality of sprockets includes a first sprocket that is disposed on the linear portion and corresponds to the first driven chain, and a second sprocket that is disposed on the curved portion and corresponds to the second driven chain. The packaging device according to claim 2.