Method and apparatus for manufacturing sanitary paper bundle products

Abstract

To enable appropriate responses to problems that occur downstream of the sanitary paper bundle sorting device. [Solution] A method for manufacturing a sanitary paper bundle product, comprising the steps of: distributing multiple sanitary paper bundles B that have been transported along a certain transport route to multiple individual transport routes using a distribution device 3; transporting the sanitary paper bundles at intervals along the multiple individual transport routes; and packaging the sanitary paper bundles that have been transported along the individual transport routes using a packaging machine 4. For a certain period of time following a malfunction of the packaging machine 4, the distribution device 3 continues to distribute the sanitary paper bundles to the unacceptable route experiencing the malfunction and to other acceptable routes. In the unacceptable route, the retention mechanism 30 stops the transport of sanitary paper bundles B downstream, while narrowing the spacing between the transported sanitary paper bundles B and accepting the distribution of sanitary paper bundles B from the distribution device 3.

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a sanitary paper product in which a bundle of sanitary paper such as tissue paper is wrapped with a flexible film or the like. The present invention also relates to an apparatus for manufacturing a sanitary paper product.

Background Art

[0002] Conventionally, a product in which sanitary paper such as tissue paper is wrapped with a resin film (so-called soft pack product) is known (Patent Document 1).

[0003] In the production of tissue paper, generally, a continuous sheet fed from a number of original rolls is folded by a multi-station interfolder (also called a multi-stand type interfolder), and then cut into individual sizes by a cutting machine to obtain a bundle of sanitary paper. Such a method is used (Patent Document 2). According to such a method, a bundle of sanitary paper can be obtained at high speed and continuously.

[0004] Furthermore, a packaging machine for automatically accommodating a plurality of articles bundled together in a packaging bag such as a resin film is also known (Patent Document 3). Such a packaging machine is configured to expand the opening of the packaging bag and then push a plurality of articles into the packaging bag through the opening while maintaining the expanded state of the packaging bag.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0006] Incidentally, when manufacturing soft pack products in which bundles of sanitary paper such as tissue paper are wrapped in resin film, it is conceivable to employ a manufacturing process in which a multi-machine is used to rapidly and continuously generate bundles of sanitary paper, and then a packaging machine such as the one described in Patent Document 3 is used to push the bundles of sanitary paper into the packaging bag. However, as mentioned above, the packaging machine for resin film requires a procedure in which the packaging bag is opened and then pushed into the packaging bag while maintaining that state, which presents the challenge of rapidly storing the bundles of sanitary paper into the packaging bag. In particular, since both the bundles of sanitary paper and the inside of the packaging bag are soft, the bundles of sanitary paper need to be pushed into the packaging bag at a relatively low speed in order to properly store them inside the packaging bag. Thus, while a multi-machine can generate bundles of sanitary paper at high speed and continuously, the fact that a film packaging machine cannot adequately keep up with the generation speed of this multi-machine is a manufacturing problem for soft pack products.

[0007] To address the above problems, the inventors are considering a method for manufacturing soft pack products in which bundles of sanitary paper obtained by a multi-machine are distributed to multiple transport routes by a sorting device, and a packaging machine is installed at each transport route to sequentially package the bundles of sanitary paper. However, when a packaging machine is placed at each transport route in this manner, the number of packaging machines increases, making it more prone to problems such as packaging machine malfunctions and paper jams. For example, if one of the multiple packaging machines malfunctions and stops functioning, and the problem with that one packaging machine is not properly addressed, all packaging machines may stop functioning, potentially leading to a decrease in manufacturing efficiency. In addition, each packaging machine may require periodic or irregular maintenance work, such as changing materials inside the packaging machine, and in such cases, it is necessary to stop one of the multiple packaging machines.

[0008] Therefore, the main objective of the present invention is to provide a technology that can appropriately address problems and maintenance work that occur downstream of a sanitary paper stack sorting device. [Means for solving the problem]

[0009] The first aspect of the present invention relates to a method for manufacturing sanitary paper bundles. The method for manufacturing sanitary paper bundles according to the present invention includes a sorting step, a conveying step, and a packaging step. In the sorting step, a plurality of sanitary paper bundles conveyed along a certain conveying path are sorted by a sorting device into a plurality of individual conveying paths. In the conveying step, the sanitary paper bundles are conveyed at intervals along the plurality of individual conveying paths. In the packaging step, the sanitary paper bundles conveyed along the individual conveying paths are packaged by a packaging machine. Each of the individual conveying paths also includes a retention mechanism. This retention mechanism is configured to accept a certain amount of sanitary paper bundles sorted from the sorting device into the individual conveying path, while stopping the discharge of sanitary paper bundles downstream of that individual conveying path and narrowing the spacing between the sanitary paper bundles being conveyed along that individual conveying path. The retention mechanism only needs to be able to narrow the spacing between the sanitary paper bundles on the individual conveying path, and is not limited to being able to stop the sanitary paper bundles on the individual conveying path. It may also be a mechanism that allows the sanitary paper bundles to be conveyed while the conveying speed of the sanitary paper bundles is reduced along the individual conveying path. Furthermore, under normal circumstances, individual transport routes can, of course, transport sanitary paper bundles downstream while maintaining the spacing between them, without utilizing the function of the retention mechanism. Here, among the multiple individual transport routes, a route where the transport of sanitary paper bundles to the downstream side is prohibited due to circumstances including trouble or maintenance work downstream is designated as an "unacceptable route," and a route where the transport of sanitary paper bundles to the downstream side is permitted even after the occurrence of such circumstances is designated as an "acceptable route." Circumstances of trouble or maintenance work primarily refer to situations where the packaging machine's function is temporarily or at least temporarily stopped, making it impossible to package sanitary paper bundles as usual. However, other situations may also occur, such as when the function of the conveyor constituting an individual transport route stops, making it impossible to transport sanitary paper bundles as usual. In this case, for at least a certain period of time after the occurrence of the trouble or maintenance work, the sorting device will continue to sort sanitary paper bundles into unacceptable and acceptable routes. Then, in the unacceptable route, the retention mechanism stops the discharge of sanitary paper bundles to the downstream side, while narrowing the spacing between the sanitary paper bundles being transported, and accepting the sanitary paper bundles sorted from the sorting device.Furthermore, after this certain period has elapsed, the sorting device may cease sorting sanitary paper bundles into routes that cannot accept them, and instead sort them only into routes that can accept them.

[0010] As described above, by providing a retention mechanism in the individual transport path between the sorting device and the packaging machine, it becomes possible to sort sanitary paper bundles to the "unacceptable path" for at least a certain period of time, even after a trouble or maintenance operation (hereinafter also referred to as "trouble, etc.") occurs. Immediately after a trouble, etc. occurs, it is often difficult to change the sorting destination of the sorting device to only the "acceptable path" due to limitations in the performance of the sorting device, etc. Therefore, by activating the retention mechanism in the "unacceptable path" and continuing to accept sanitary paper bundles there, the production of sanitary paper bundles can be continued without forcing the sorting device to operate unnaturally. Furthermore, by providing such retention mechanisms in each individual transport path in preparation for trouble, etc., it becomes possible to reduce the number of sanitary paper bundles sent to the sorting device per unit time after a trouble, etc. occurs, or to gain time to adjust the operation of the sorting device. This allows for appropriate responses to troubles, etc. that occur downstream of the sanitary paper bundle sorting device. In addition, if trouble, etc. in one packaging machine cannot be appropriately addressed, all packaging machines may shut down, which could lead to a decrease in manufacturing efficiency. Specifically, if a problem occurs in the packaging machine or during intermediate transport, the sanitary paper bundles will remain on the upstream conveyor all the way to the sorting device. If the normal transport equipment continues to operate, the problem will escalate as the bundles collide with the faulty area. To avoid such problems, the transport equipment must be stopped immediately. However, even if one sorting line stops, the total amount transported from the cutting equipment remains unchanged. Therefore, even if the paper is only sorted to packaging machines that can accept it, this can lead to other problems such as insufficient processing capacity in individual sorting devices or insufficient overall processing capacity in the packaging machines that can accept it. According to the present invention, such problems can be avoided in advance.

[0011] In the manufacturing method according to the present invention, after a certain period of time has elapsed since the occurrence of a problem or other issue, it is preferable that the sorting device stops sorting sanitary paper bundles to unacceptable routes and sorts them only to acceptable routes. After a certain period of time has elapsed since the occurrence of a problem or other issue, preparations are often made to reduce the amount of sanitary paper bundles supplied to the sorting device or to exclude unacceptable routes from the sorting device's distribution destinations. For this reason, after such preparations are made, it is preferable to stop sorting sanitary paper bundles to unacceptable routes and sort them only to other acceptable routes.

[0012] In the manufacturing method according to the present invention, the retention mechanism may include an accumulator. The accumulator has a conveying section on the conveying surface of the sanitary paper stack that conveys the sanitary paper stack by frictional force generated between it and the lower surface of the sanitary paper stack, and an idle section in which a contact element that contacts the lower surface of the sanitary paper stack rotates freely. By using such an accumulator, the retention function in the event of trouble or other issues can be efficiently performed.

[0013] In the manufacturing method according to the present invention, the retention mechanism may include a roller conveyor, a drive device, and a switching device. The roller conveyor has a plurality of rollers that can rotate freely. The drive device rotates the rollers in a certain direction. The switching device switches between a driven state in which the drive device rotates the rollers and a free-rotating state in which the rotation of the rollers by the drive device is stopped and the rollers can rotate freely. When a problem or other circumstance occurs, the switching device that constitutes the retention mechanism for the unacceptable path switches from the driven state to the free-rotating state. By using a roller conveyor with such a switching device, the retention function in the event of a problem or other circumstance can be efficiently performed.

[0014] In the manufacturing method according to the present invention, the retention mechanism may be equipped with a plurality of conveyors that can be individually controlled for starting and stopping. In this way, the retention mechanism can also be realized using a plurality of conveyors.

[0015] In the manufacturing method according to the present invention, the conveyor may have a conveying surface of a length that allows for the simultaneous transport of multiple bundles of sanitary paper. By ensuring a relatively long conveying surface for the multiple conveyors constituting the retention mechanism in this way, it becomes possible to accommodate, for example, a configuration in which multiple bundles of sanitary paper are grouped together and distributed to individual transport paths.

[0016] A second aspect of the present invention relates to a manufacturing apparatus for sanitary paper bundle products. This manufacturing apparatus comprises a sorting device, a plurality of conveying devices, and a packaging machine. The sorting device sorts a plurality of sanitary paper bundles that have been transported along a certain transport route into a plurality of individual transport routes. The plurality of conveying devices transport the sanitary paper bundles at intervals along the plurality of transport routes. The packaging machine packages the sanitary paper bundles that have been transported along the individual transport routes. Each of the conveying devices has a retention mechanism. The retention mechanism is configured to accept a certain amount of sanitary paper bundles sorted from the sorting device into its individual transport route, while stopping the discharge of sanitary paper bundles downstream of its individual transport route and narrowing the spacing between the sanitary paper bundles being transported along that individual transport route. Here, among the plurality of individual transport routes, a route in which the discharge of sanitary paper bundles to the downstream side is prohibited due to circumstances including troubles on the downstream side is called an "unacceptable route," and a route in which the discharge of sanitary paper bundles to the downstream side is permitted even after the occurrence of such circumstances is called an "acceptable route." In this case, for at least a certain period of time following the occurrence of trouble or other circumstances, the sorting device will continue to sort the sanitary paper bundles into unacceptable and acceptable routes. In the unacceptable route, the retention mechanism will stop the downstream transport of the sanitary paper bundles while narrowing the spacing between the transported sanitary paper bundles, and will accept the sanitary paper bundles sorted from the sorting device. [Effects of the Invention]

[0017] According to the present invention, it becomes possible to appropriately respond to troubles and the like that occur on the downstream side of the distributor of the toilet paper bundle. In particular, according to the present invention, even immediately after the occurrence of troubles and the like, manufacturing can be continued without forcing the distributor to perform unreasonable operations, and time for adjusting the supply amount of the toilet paper bundle and the operation of the distributor can be secured.

Brief Description of the Drawings

[0018] [Figure 1] It is a schematic diagram showing a manufacturing method and a manufacturing apparatus for a toilet paper bundle product. [Figure 2] It shows an embodiment of the distributor. [Figure 3] It shows an example of the switching operation of the conveyance path by the distributor. [Figure 4] It schematically shows the state of distribution of the toilet paper bundle by the distributor. [Figure 5] It schematically shows the conveyance path from the distributor to the packaging machine. [Figure 6] It schematically shows an operation example of the conveyor with a retention mechanism. [Figure 7] It shows an embodiment of the retention mechanism using an accumulation conveyor. [Figure 8] It shows an embodiment of the retention mechanism using a roller conveyor with a drive unit. [Figure 9] It shows an embodiment of the retention mechanism by starting and stopping control of a plurality of conveyors. [Figure 10] It shows an embodiment of the retention mechanism by starting and stopping control of a plurality of conveyors. [Figure 11] It shows an embodiment of the retention mechanism using the difference in conveyance speed. [Figure 12] It shows a configuration example of the interval adjustment mechanism. [Figure 13] It shows an example of the operation of the interval adjustment mechanism. <​​​​​​

[0019] The following describes embodiments for carrying out the present invention with reference to the drawings. The present invention is not limited to the embodiments described below, but also includes modifications made to the embodiments described below within the scope that would be obvious to those skilled in the art.

[0020] Figure 1 shows a method for manufacturing a sanitary paper bundle product, illustrating the process from obtaining the sanitary paper bundle B using a multi-folder 1 to packaging it with a packaging machine 4. As shown in Figure 1, the multi-folder 1 folds sanitary paper P (base paper) unfurled from numerous rolls to form a continuous laminate of sanitary paper P. The multi-folder 1 is equipped with a number of rolls corresponding to the number of sanitary paper bundles. For example, to obtain a product consisting of 200 sets of two-ply tissues (400 sheets in total), the multi-folder 1 is equipped with 200 sets of two-roll rolls (400 rolls in total). Such a multi-folder 1 (multi-stand interfolder) can be a known type. Next, the laminate of sanitary paper P formed by the multi-folder 1 is transported downstream and cut at predetermined intervals by a cutting machine 2. This results in individual sanitary paper bundles B. A known rotary cutter can be used as the cutting machine 2. In this way, sanitary paper bundles B can be produced at high speed and continuously. In sanitary paper stack B, each sheet of sanitary paper is folded in half, and the halves of two other sheets of sanitary paper are inserted between each sheet, so that when one sheet of sanitary paper is lifted, the sheets below it also lift up, creating a pop-up style stack.

[0021] Subsequently, multiple stacks of sanitary paper B are transported downstream in a single line by a conveyor or the like. There is a speed difference between the transport speed of the sanitary paper B within the cutting device 2 and the transport speed of the sanitary paper B by the conveyor immediately following it, with the transport speed of the sanitary paper B by the conveyor immediately following being set to be faster. This widens the spacing between the sanitary paper B stacks. A sorting device 3 is provided downstream of the cutting device 2. An example of the sorting device 3 will be described later, but any form of sorting device 3 can be adopted as long as it has the function of distributing multiple stacks of sanitary paper B that have been transported in a single line along one transport path to multiple transport paths. It is also advisable to install a known discharge device in the transport path between the cutting device 2 and the sorting device 3 that detects defects in the sanitary paper B and discharges the sanitary paper B that are deemed defective. Such a discharge device is placed for purposes such as discharging sanitary paper B that are not ready to be sold at the initial stage, or discharging sanitary paper B that are not ready to be sold in the event of a sudden stop due to trouble in a downstream process. In the example shown in Figure 1, multiple stacks of sanitary paper B are distributed to three transport paths. Note that the number of transport paths for sanitary paper B is not limited to three; there may be two or more. In this case, as shown in Figure 1, the transport path may be switched every predetermined number of sanitary paper B. For example, in the example in Figure 1, the transport path is switched every four sanitary paper B. That is, the distribution device 3 outputs a predetermined number (four) of sanitary paper B to a certain transport path, then switches the transport path, and repeatedly outputs another predetermined number of sanitary paper B to an adjacent transport path. When switching from the transport paths on both sides to the central transport path, it is preferable to send a predetermined number (e.g., four) of sanitary paper B to the side sanitary paper B twice (e.g., eight) before switching to the central transport path. This ensures that an equal amount of sanitary paper B is ultimately sent from the transport paths on both sides and the central transport path. On the other hand, as will be described later with reference to Figure 14, the transport route may be switched for each individual stack of sanitary paper B. In this case, the sorting device 3 needs to be operated at a higher speed compared to the case where the transport route is switched for each of the multiple stacks of sanitary paper B described above.

[0022] Furthermore, a packaging machine 4 is provided downstream of each transport path. The packaging machine 4 should be one that has the function of packaging one or more bundles of sanitary paper B into flexible packaging bags such as resin film. The packaging bags are preferably made of resin such as polyethylene, polypropylene, polyvinyl chloride, polyester, or polyvinyl acetate. However, the packaging bags may also be paper bags. As such a packaging machine, a known one such as the one disclosed in Patent Document 3 can be used. In this way, a sanitary paper bundle product (a so-called soft pack product) can be manufactured by packaging one or more bundles of sanitary paper B in packaging bags. Alternatively, the sanitary paper bundle product may be a product in which multiple individually packaged sanitary paper bundles B are bundled together and packaged in another packaging bag.

[0023] Figure 2 shows an example of a sorting device 3. However, the sorting device 3 is not limited to the example shown here; as mentioned above, any form can be adopted as long as it has the function of sorting multiple bundles of sanitary paper B that have been transported in a single line along one transport path into multiple transport paths. In the example shown in Figure 2, the sorting device 3 comprises a conveyor device 10 for transporting the bundles of sanitary paper B and a sorting conveyor 20 for sorting the bundles of sanitary paper B. In the example shown in Figure 2, the sorting conveyor 20 is depicted as supporting the bundles of sanitary paper B only from the bottom side in order to make the position of the bundles of sanitary paper B easier to understand. Thus, the sorting conveyor 20 may be configured to have a conveyor device only on the bottom side of the bundles of sanitary paper B, but the sorting conveyor 20 may also be configured to have upper and lower conveyor devices for sandwiching the bundles of sanitary paper B from both the bottom and top sides (not shown).

[0024] The conveyor system 10 includes, in order from upstream, a main conveyor 11, a distribution conveyor 20, a wide conveyor 12, and multiple individual conveyors 13(a) to (c). Each conveyor 11 to 13, 20 can be a general conveyor with a structure in which an endless belt is stretched over pulleys including a drive pulley and a driven pulley. The main conveyor 11 transports the sanitary paper bundles B in a single line and hands them over to the distribution conveyor 20. The distribution conveyor 20 switches the transport path of the sanitary paper bundles B. The distribution conveyor 20 also hands over the sanitary paper bundles B to the wide conveyor 12 while switching the transport path. As a result, multiple transport paths for the sanitary paper bundles B are formed in parallel on the wide conveyor 12. Downstream of the wide conveyor 12, several individual conveyors 13(a) to (c) are arranged in parallel, with each individual conveyor 13(a) to (c) corresponding to a transport path on the wide conveyor 12. In other words, the wide conveyor 12 transfers the sanitary paper bundles B to one of the individual conveyors 13(a) to (c) according to the transport path switched by the sorting conveyor 20. As shown in Figure 2, the wide conveyor 12 is designed to have a width at least greater than the sum of the widths of the individual conveyors 13(a) to (c). Furthermore, to ensure stable sorting during high-speed transport, the sorting conveyor 20 may be equipped with a function that allows its tip to extend and retract during the transport path switching operation, and it may extend and retract in sync with the transport of the product bundles while performing the sorting operation.

[0025] The sorting conveyor 20 is positioned between the main conveyor 11 and the wide conveyor 12. All bundles of sanitary paper B transported by the main conveyor 11 are introduced into the sorting conveyor 20, guided by the sorting conveyor 20, and then transferred from the wide conveyor 12 to one of the individual conveyors 13(a) to (c). As shown in Figure 2, the sorting conveyor 20 has a predetermined pivot point 21. The output end of the sorting conveyor 20 rotates horizontally with respect to the predetermined pivot point 21, that is, along the conveying surface of the wide conveyor 12. Specifically, the pivot point 21 for the rotation of the sorting conveyor 20 is located on its input end (i.e., the end that receives the bundles of sanitary paper B). Therefore, the position of the input end of the sorting conveyor 20 is almost fixed immediately behind the main conveyor 11, but the output end of the sorting conveyor 20 undergoes a significant transition on the wide conveyor 12 side. The rotational movement of the distribution conveyor 20 relative to the pivot point 21 can be achieved by known actuators such as motors and pistons. Furthermore, the rotational movement of the distribution conveyor 20 is controlled by a control device (not shown), such as a computer.

[0026] Furthermore, the sorting conveyor 20 includes a sensor 22 near its output end or within its guidance path. This sensor 22 is positioned to identify the gaps between stacks of sanitary paper B that are led from the sorting conveyor 20 to the wide conveyor 12. Specifically, the sensor 22 detects the presence or absence of stacks of sanitary paper B near the tip of the sorting conveyor 20 or within its guidance path, thereby identifying when the gaps between stacks of sanitary paper B are approaching the tip of the sorting conveyor 20. Based on the detection information from the sensor 22, a control device (not shown) controls the sorting conveyor 20, and when a gap occurs between stacks of sanitary paper B near the tip of the sorting conveyor 20, the sorting conveyor 20 is rotated to switch the transport path of the stacks of sanitary paper B. The sensor 22 can also measure the length of the gap between stacks of sanitary paper B. If the distance between stacks of sanitary paper B is greater than or equal to a certain length, the transport path for the stacks of sanitary paper B is switched at that distance. If the distance is less than that distance, the transport path is not switched at that distance. The sensor 22 is not particularly limited as long as it can detect the presence or absence of stacks of sanitary paper B, and known sensors such as optical sensors (photoelectric sensors), ultrasonic sensors, and pressure sensors can be used. Furthermore, the transport path switching can be performed by setting a timer after the gap between stacks of sanitary paper B is detected by the sensor 22 (to perform the switch after a predetermined time has elapsed since detection) or by adjusting the position of the sensor 22.

[0027] Next, with reference to Figure 3, the operation of the sorting conveyor 20 will be explained. As shown in Figure 3, the sorting conveyor 20 rotates its output end around the pivot point 21. This allows the sorting conveyor 20 to switch the transport path of the sanitary paper bundles B on the wide conveyor 12. In the state shown in Figure 3, the first to third individual conveyors 13(a) to (c) are arranged in parallel at the destination of the wide conveyor 12. Here, in the state shown in Figure 3(a), multiple sanitary paper bundles B that have been continuously transported by the main conveyor 11 are introduced into the sorting conveyor 20, and then guided by this sorting conveyor 20 to the transport path on the wide conveyor 12 that leads to the third individual conveyor 13(c).

[0028] Subsequently, as shown in Figure 3(b), when the sorting conveyor 20 sends a predetermined number (for example, 4) of sanitary paper bundles B to the transport path toward the third individual conveyor 13(c), it starts switching the transport path to send the next predetermined number of sanitary paper bundles B to the second individual conveyor 13(b). At this time, based on the detection information from the sensor 22 installed in the guidance path of the sorting conveyor 20, the control device can determine that a predetermined number of sanitary paper bundles B have been led out of the sorting conveyor 20 and that the gaps between the sanitary paper bundles B have reached the vicinity of the output end of the sorting conveyor 20, and then control the sorting conveyor 20 to start the transport path switching operation.

[0029] As shown in Figure 3(b), when the transport path is switched, the sanitary paper bundle B' located at the front of the sorting conveyor 20 may have part of it on the sorting conveyor 20 and another part on the wide conveyor 12. In this state, with the sanitary paper bundle B' acting as a bridge between the sorting conveyor 20 and the wide conveyor 12, when the sorting conveyor 20 rotates to switch the transport path, the sanitary paper bundle B' will slide on the transport surface of the wide conveyor 12. At this time, to prevent the sanitary paper bundle B' from losing its shape, the sorting conveyor 20 may be configured to rotate around a predetermined pivot point 21 while gripping at least part of the sanitary paper bundle B' from above and below, thereby switching the transport path.

[0030] Subsequently, as shown in Figure 3(c), when the sorting conveyor 20 sends a predetermined number (for example, 4) of sanitary paper bundles B to the transport path toward the second individual conveyor 13(b), it starts switching the transport path to send the next predetermined number of sanitary paper bundles B to the transport path toward the first individual conveyor 13(a). At this time, based on the detection information from the sensor 22 installed in the guidance path of the sorting conveyor 20, the control device can determine that a predetermined number of sanitary paper bundles B have been led out of the sorting conveyor 20 and that the gaps between the sanitary paper bundles B have reached the vicinity of the output end of the sorting conveyor 20, and then control the sorting conveyor 20 to start the transport path switching operation.

[0031] Furthermore, the ratio of the length of the guidance path of the distribution conveyor 20 to the swing width of one pitch when the distribution conveyor 20 switches the transport path is preferably 1:5 or more, more preferably 1:8 or more, and particularly preferably 1:10 or more. If this ratio is small, the swing angle becomes large, making it easy for wrinkles and collapse to occur in the sanitary paper bundles B, so it is good to ensure this ratio is 1:5 or more. Also, as mentioned above, when switching from the transport paths on both sides (first individual conveyor 13(a), third individual conveyor 13(c)) to the central transport path (second individual conveyor 13(b)), it is preferable to send a predetermined number (e.g., 4 bundles) of sanitary paper bundles B to the side sanitary paper bundles twice (e.g., 8 bundles) before switching to the central transport path. This ensures that ultimately an equal amount of sanitary paper bundles B are sent out by the transport paths on both sides and the central transport path.

[0032] Next, referring to Figure 4, we will explain the distribution of paper to individual transport paths by the distribution device 3 and how to deal with problems that occur in the packaging machine 4 downstream of the transport path. For example, as shown in Figure 4(a), let's assume that during normal operation, 300 bundles of sanitary paper B are supplied to the distribution device 3 per unit time (t). In this example, let's assume that the distribution device 3 has the capacity to distribute these bundles of sanitary paper B evenly to three individual transport paths. In this case, the packaging machines 4(a) to 4(c) located downstream of the transport path will each package 100 bundles of sanitary paper B per unit time (t). The unit time (t) can be set arbitrarily, but for example, it can be set to 1 minute.

[0033] In this example, suppose a problem occurs in the first packaging machine 4(a) of the three packaging machines 4, as shown in Figure 4(b), and the packaging function is temporarily stopped. In this case, it is undesirable to send the sanitary paper bundles B to the transport path leading to the first packaging machine 4. Therefore, in the example shown in Figure 4(b), the sorting device 3 is configured to distribute the 300 bundles / ton of sanitary paper bundles B to the transport paths leading to the second packaging machine 4(b) and the third packaging machine 4(c), which are functioning normally. Compared to the state where the sanitary paper bundles B are distributed to three transport paths (during normal operation), when the sanitary paper bundles B are distributed to only two transport paths (during a problem), the sorting device 3 is required to perform a more agile distribution operation. In the example shown in Figure 4(b), the sorting device 3 has a swift sorting capability, so even when the first packaging machine 4(a) is stopped, it can sort the entire amount of sanitary paper bundles B to the remaining two packaging machines 4(b) and 4(c) which are operating normally. Specifically, the sorting device 3 sorts 300 bundles / ton of sanitary paper bundles B into transport paths leading to the two packaging machines 4(b) and 4(c), and the two packaging machines 4(b) and 4(c) each package 150 bundles / ton of sanitary paper bundles B.

[0034] The example shown in Figure 4(b) illustrates a case where the sorting capacity of the sorting device 3 is sufficiently high. However, depending on the performance of the sorting device 3, the sorting capacity may be insufficient, and it is conceivable that the sorting of such sanitary paper bundles B may not be adequately performed. For example, as shown in Figure 4(c), the sorting device 3 has insufficient sorting capacity, making it difficult to sort 300 bundles / ton of sanitary paper bundles B to only the two packaging machines 4(b) and 4(c). In this case, the sorting device 3 sorts 100 bundles / ton of sanitary paper bundles B not only to the transport route leading to the two normally operating packaging machines 4(b) and 4(c), but also to the transport route leading to the first packaging machine 4(a) where a problem has occurred. In such cases, it is necessary to reduce the number of sanitary paper bundles B supplied to the sorting device 3. For example, in the example shown in Figure 4(b), the amount of sanitary paper bundles B supplied to the sorting device 3 is reduced from 300 bundles / ton to 200 bundles / ton. By reducing the supply of sanitary paper bundles B to the sorting device 3 in this way, even a packaging machine 4 with low sorting capacity can supply sanitary paper bundles B only to the two normally operating packaging machines 4(b) and 4(c). However, in this case, it is necessary to adjust the equipment further upstream than the sorting device 3 to reduce the supply of sanitary paper bundles B to the sorting device 3. Since this adjustment takes time, the sorting operation to a total of three transport routes, including the transport route leading to the first packaging machine 4(a) where the trouble is occurring, will continue until the supply of sanitary paper bundles B is reduced (i.e., until the supply adjustment from 300 units / ton to 200 units / ton is completed). In this case, sanitary paper bundles B will continue to be supplied to the transport route leading to the first packaging machine 4(a), but since the first packaging machine 4(a) cannot package sanitary paper bundles B, the sanitary paper bundles B will accumulate in this transport route. Depending on the length of the transport path leading to the first packaging machine 4(a), if the distribution of sanitary paper bundles B to this transport path continues at this rate, the transport path will eventually become full of sanitary paper bundles B, causing other problems such as jams in the transport path or detachment of sanitary paper bundles B from the transport path.

[0035] In particular, as shown in Figures 1 and 3, for example, bundles of sanitary paper B are supplied to each transport path at predetermined intervals. However, if the spacing between bundles of sanitary paper B on the transport path remains wide, the time it takes for the transport path to become full of sanitary paper B will be shortened. Therefore, one of the objectives of this invention is to intentionally reduce the spacing between bundles of sanitary paper B supplied to a transport path where problems are occurring, thereby allowing as many bundles of sanitary paper B as possible to remain on the transport path, and thus extending the time it takes for the transport path to become full of sanitary paper B.

[0036] As shown in Figure 4(d), it is also possible to continue distributing sanitary paper bundles B to the transport path leading to the packaging machine 4(a) that has stopped due to trouble, while appropriately discharging the sanitary paper bundles B supplied to this transport path until the adjustment of the supply amount to the distribution device 3 is completed. In this way, it is possible to prevent other troubles from occurring on the transport path. In addition, if the time until the adjustment of the supply amount is completed is short, the amount of sanitary paper bundles B to be discarded will also be reduced. It is also possible to optionally apply this technology of discharging sanitary paper bundles B on a transport path that is experiencing trouble to the present invention.

[0037] Next, Figure 5 schematically shows the transport paths from the sorting device 3 to each packaging machine 4(a) to 4(c). Each transport path is composed of multiple individual conveyors 13 arranged in a row. In particular, in this embodiment, each transport path is provided with a retention mechanism 30 to efficiently retain sanitary paper bundles B in case a problem occurs in the packaging machine 4 or the like and it becomes impossible to transport the sanitary paper bundles B downstream. This retention mechanism 30 is configured to stop transporting the sanitary paper bundles B downstream of the transport path, while narrowing the spacing between the sanitary paper bundles B being transported along that transport path, in the event that the transport path is prohibited from transporting the sanitary paper bundles B downstream due to a problem in the packaging machine 4 or the like, and to accept a certain amount of sanitary paper bundles B distributed from the sorting device 3 into that transport path. Specifically, among several individual transport routes, the route where the transport of sanitary paper bundles B to the downstream side is prohibited due to circumstances including troubles on the downstream side is designated as the "unacceptable route," and the route where the transport of sanitary paper bundles B to the downstream side is permitted even after the occurrence of these circumstances is designated as the "acceptable route." In this case, for at least a certain period of time after the occurrence of troubles, the sorting device 3 continues to sort the sanitary paper bundles B to the unacceptable route and the acceptable route. In the unacceptable route, the retention mechanism 30 stops the transport of sanitary paper bundles B to the downstream side, while narrowing the spacing between the transported sanitary paper bundles B, allowing the sorting device 3 to accept the sanitary paper bundles B.

[0038] In the example shown in Figure 5, three transport paths are provided in parallel downstream of the sorting device 3. The first transport path is formed by the first individual conveyor 13(a), the second transport path is formed by the second individual conveyor 13(b), and the third transport path is formed by the third individual conveyor 13(c). The first individual conveyor 13(a) includes, in order from upstream, the first conveyor 13(a)(1), the second conveyor 13(a)(2), and the third conveyor 13(a)(3). Similarly, the second individual conveyor 13(b) also includes, in order from upstream, the first conveyor 13(b)(1), the second conveyor 13(b)(2), and the third conveyor 13(b)(3). Similarly, the third individual conveyor 13(c) includes, in order from the upstream side, the first conveyor 13(c)(1), the second conveyor 13(c)(2), and the third conveyor 13(c)(3). Of the conveyors that make up each of these transport paths, the first conveyors 13(a)(1), 13(b)(1), 13(c)(1) and the second conveyors 13(a)(2), 13(b)(2), 13(c)(2), which are located after the sorting device 3, are each equipped with a retention mechanism 30.

[0039] In this embodiment, among the conveyors constituting each transport path, the third conveyors 13(a)(3), 13(b)(3), and 13(c)(3) located directly in front of the packaging machine 4 are equipped with a spacing adjustment mechanism 40. The spacing adjustment mechanism 40 will be explained after the explanation of the retention mechanism 30. In Figure 5, the third conveyors 13(a)(3)... with the spacing adjustment mechanism 40 are schematically shown as a single conveyor, but these third conveyors 13(a)(3)... with the spacing adjustment mechanism 40 may be composed of multiple conveyors.

[0040] Figure 6 mainly shows an example of the operation of a conveyor equipped with a retention mechanism 30. For simplicity, Figure 6 uses the first individual conveyor 13(a) that forms the first transport path as an example. First, Figure 6(a) shows the transport state of the sanitary paper bundle B during normal operation. As shown in Figure 6(a), the sorting device 3 distributes the sanitary paper bundle B to the first individual conveyor 13(a) at predetermined intervals. During normal operation, the sanitary paper bundle B is transported as usual through the first conveyor 13(a)(1), the second conveyor 13(a)(2), and the third conveyor 13(a)(3) to the first packaging machine 4(a) at the downstream end, where it is individually packaged. As mentioned above, of these conveyors, the first conveyor 13(a)(1) and the second conveyor 13(a)(2) are equipped with a retention mechanism 30 to prepare for the occurrence of troubles, etc., and the third conveyor 13(a)(3) is equipped with a spacing adjustment mechanism 40.

[0041] Figure 6(b) shows an example where, for example, a malfunction or paper jam occurs in the first packaging machine 4, and the first transport route becomes an unacceptable route where the discharge of sanitary paper bundles B to the downstream side is prohibited. As shown in Figure 6(b), at the time the trouble occurs, a stopper 14 located immediately after the second conveyor 13(a)(2) with a retention mechanism 30 is activated. In this embodiment, the stopper 14 is located between the second conveyor 13(a)(2) and the third conveyor 13(a)(3). This stopper 14 blocks the flow of sanitary paper bundles B. As shown in Figure 6(b), even after the stopper 14 is activated due to the trouble, the sorting device 3 continues to supply sanitary paper bundles B to the first transport route sequentially at predetermined intervals. Furthermore, even after a problem occurs, the sanitary paper bundles B on the first transport path are transported downstream by the action of the first conveyor 13(a)(1) and the second conveyor 13(a)(2). At this time, the leading sanitary paper bundle B on the second conveyor 13(a)(2) comes into contact with the stopper 14, and is no longer transported downstream. When this leading sanitary paper bundle B stops, the subsequent sanitary paper bundles B come into contact with this leading sanitary paper bundle B and stop. In this way, the spacing between each sanitary paper bundle B narrows, starting with the sanitary paper bundle B in contact with the stopper 14. Thus, on the first conveyor 13(a)(1) and the second conveyor 13(a)(2) equipped with the retention mechanism 30, the sanitary paper bundles B line up closer together and eventually stop. The final spacing between the sanitary paper bundles B is definitely narrower than the spacing when the sorting device 3 sorts the sanitary paper bundles B onto the transport path. This allows more sanitary paper bundles B to be retained on the transport path where problems occur. Furthermore, when the downstream conveyor is full of sanitary paper bundles B, the incoming sanitary paper bundles B can act as a stopper by connecting to the full stack of sanitary paper bundles B. In this case, the mechanical stopper 14 can be omitted.

[0042] Furthermore, Figure 6(c) shows the state when the transport of sanitary paper bundles B from the sorting device 3 to the first transport path has stopped. As shown in Figure 6(c), when sorting from the sorting device 3 stops, the transport of sanitary paper bundles B by the first conveyor 13(a)(1) and the second conveyor 13(a)(2) with the retention mechanism 30 also basically stops. At this time, since the sanitary paper bundles B are lined up closely together on these conveyors 13(a)(1) and 13(a)(2), more sanitary paper bundles B can be temporarily accepted on these conveyors. In the example shown in Figure 6(c), there is still room on these conveyors 13(a)(1) and 13(a)(2) to accept more sanitary paper bundles B. In this way, even after a problem occurs, by allowing sanitary paper bundles B to be accepted on the first transport path (unacceptable path) for a certain period of time, time can be secured to adjust the supply amount of sanitary paper bundles B and adjust the operation of the sorting device 3.

[0043] Furthermore, the "certain period" after a problem occurs that prevents the acceptance of sanitary paper bundle B, as referred to here, is the period until the speed of the upstream process (specifically, the cutting machine) decreases to a speed that can be processed by the downstream process (specifically, the packaging machine), as shown in Figure 4(c), for example. More precisely, it is the period including the time it takes for the sanitary paper bundles, whose processing speed has decreased, to reach the downstream process (sorting equipment). In other words, if the supply volume of sanitary paper bundles exceeds the total processing capacity of the packaging machines, which have reduced the number of operating machines due to the problem, the cutting speed of the sanitary paper needs to be reduced to below this total processing capacity.

[0044] Furthermore, "a certain period" can refer to, for example, the period during which the sorting device distributes multiple bundles of sanitary paper to their respective transport routes, until one cycle is completed for the distribution to the transport route where a problem occurred. In this case, when the sorting device distributes multiple bundles of sanitary paper to their respective transport routes, it is not possible to instantly switch to another line during the distribution to a transport route that has stopped due to a problem, so it is necessary to continue the operation as is. However, after the problem occurs, the paper only needs to be distributed to other transport routes. However, if the packaging capacity of the downstream process is insufficient, it will ultimately be necessary to reduce the cutting speed in the upstream process. In this case, it is possible to reduce the cutting speed over time after the distribution of the sanitary paper bundles has been handled. Moreover, when the sorting device distributes multiple bundles of sanitary paper to their respective transport routes, the "certain period" during which an unacceptable route accepts sanitary paper bundle B can be handled in such a short time (one cycle), which has the advantage of requiring less accumulation.

[0045] Furthermore, "a certain period" refers to the period until the speed of the upstream process (cutting machine) decreases to a speed that the sorting capacity of each sorting machine can handle, when sorting sanitary paper bundles one by one to each transport path by sorting machines. More precisely, it is the period including the time it takes for the sanitary paper bundles, whose processing speed has decreased, to reach the downstream process (sorting equipment). In this way, when sorting machines sort sanitary paper bundles one by one to each transport path, if the processing capacity of each sorting machine is sufficient (for example, if the number of sorts per unit time is 150 bundles / ton in the example shown in Figure 4(b)), it is possible to switch the sorting destination instantaneously. On the other hand, if the processing capacity of the sorting machine is insufficient (for example, if the number of sorts per unit time is 100 bundles / ton or more but less than 150 bundles / ton in the example shown in Figure 4(b)), the sorting operation will continue, and the cutting machine's speed will be reduced while continuing to supply to the non-receiving paths, and the sorting destination will be switched when the speed has decreased (see Figure 4(c)). Alternatively, it is possible to switch the sorting destination instantaneously while discharging a portion of the material (as shown in Figure 4(d) with 300 cutters). Furthermore, the issue can be addressed by then reducing the speed of the cutters to eliminate the discharge altogether. Note that insufficient processing capacity of the sorting device means that the number of materials dispensed (sorted) per unit time is low.

[0046] Next, with reference to Figures 7 to 11, a specific embodiment for realizing the retention mechanism 30 schematically shown in Figure 6 will be described.

[0047] In the embodiment shown in Figure 7, the retention mechanism 30 is realized by using an accumulator 31 as the individual conveyor 13. The accumulator 31 is configured to allow the sanitary paper bundles B to be transported while reducing the frictional force between the sanitary paper bundles B and the belt, by providing multiple freely rotating free rollers 31d on the belt for transporting the sanitary paper bundles B.

[0048] To explain in more detail, as shown in the side view of Figure 7, the accumulation conveyor 31 includes an endless plate conveyor belt 31a in which multiple plates extending in the width direction are connected in the circumferential direction (rotation direction), a drive pulley 31b that is rotated by a drive device such as a motor (not shown), and a driven pulley 31c that is rotated by receiving power from the drive pulley 31b via the plate conveyor belt 31a. The plate conveyor belt 31a is stretched over the drive pulley 31b and the driven pulley 31c, and is driven by the drive pulley 31b, transmitting its power to the driven pulley 31c, which rotates the driven pulley 31c. Also, as shown in the perspective view of Figure 7, multiple free rollers 31d that rotate freely via a rotating shaft are attached to the plate conveyor belt 31a between the plates that make up the belt. These free rollers 31d rotate in the same direction as the drive pulley 31b, etc., but a part of their circumferential surface protrudes slightly from the surface of the plate conveyor belt 31a. Furthermore, the free rollers 31d are not provided across the entire surface of the plate conveyor belt 31a; there are also conveying surfaces 31e between the free rollers 31d and on the outer side in the width direction where the free rollers 31d are not present. Similar to a normal conveyor belt, frictional force is generated between the conveyed object (bundle of sanitary paper B) and this frictional force allows the object to be transported. Therefore, when a bundle of sanitary paper B is placed on the surface of the plate conveyor belt 31a, a portion of the underside of the bundle of sanitary paper B rests on the free rollers 31d, while other parts rest on the conveying surfaces. When the bundle of sanitary paper B is not in contact with other obstacles on the surface of the plate conveyor belt 31a, it is transported downstream by the frictional force between it and the conveying surfaces 31e as the plate conveyor belt 31a is driven. On the other hand, if the sanitary paper stack B comes into contact with other obstacles on the surface of the plate conveyor belt 31a, it will remain in place without being dragged along the conveying surface 31e due to the free rotation of the free roller 31d.Therefore, by using this accumulator 31, even when the plate conveyor belt 31a is continuously driven by the rotation of the drive pulley 31b, the sanitary paper bundle B can be kept on the surface of the plate conveyor belt 31a. In particular, since the sanitary paper bundle B is made up of multiple stacks of sanitary paper, if the frictional force between it and the surface of the plate conveyor belt 31a is large, there is a risk that the sanitary paper will curl up or the bundle will collapse if it is left in a specific position on the surface. In this respect, the accumulator 31 reduces the frictional force by providing multiple free rollers 31d on the plate conveyor belt 31a, so even if the sanitary paper bundle B is left in a specific position on the surface, curling up of the sanitary paper is less likely to occur.

[0049] Furthermore, it is preferable to switch the speed of the accumulator 31 to a low speed when the downstream process stops. If it continues to operate at high speed, when the sanitary paper bundles B accumulate, the large speed difference with the accumulator 31 may cause wrinkles to form on the contact surface of the sheets, or in some cases, damage such as tearing. Moreover, if the recovery is prolonged, it is desirable to set a timer or to stop the accumulator 31 after the distribution equipment has stopped distributing to the relevant line.

[0050] In the embodiment shown in Figure 8, the retention mechanism 30 is realized by using a roller conveyor 32 with a drive unit as the individual conveyor 13. This roller conveyor 32 with a drive unit consists of a roller conveyor 32a with a conveying surface formed by a plurality of freely rotating rollers, and a drive unit that rotates these rollers in a certain direction. By detaching this drive unit from the rollers as needed, it is possible to switch between a configuration in which the rollers are driven and a configuration in which the rollers rotate freely.

[0051] To explain in more detail, as shown in Figure 8(a), a roller conveyor 32a equipped with multiple freely rotating rollers is supported by a frame 32b, and the upper surface of the roller conveyor 32a serves as the conveying surface for transporting the sanitary paper bundles B. On the other hand, a drive unit for driving the multiple rollers is provided on the lower surface of the roller conveyor 32a. This drive unit comprises an endless drive belt 32c, a drive pulley 32d, and one or more driven pulleys 32e, with the drive belt 32c stretched between the drive pulley 32d and the driven pulleys 32e. The drive pulley 32d rotates due to power from a drive device 32f including a motor, driving the drive belt 32c. Furthermore, when transporting the sanitary paper bundles B (during normal operation), the drive belt 32c is in close contact with the lower surface of the multiple rollers that make up the roller conveyor 32a, and when the drive belt 32c is driven, the multiple rollers also rotate in a certain direction. As the rollers of the roller conveyor 32a rotate, the bundle of sanitary paper B placed on them is transported downstream.

[0052] On the other hand, as shown in Figure 8(b), when it is necessary to keep the sanitary paper bundles B on the roller conveyor 32a, such as when a problem occurs with the packaging machine 4, the lifting device 32g is operated to separate the drive belt 32c from the roller conveyor 32a. This lifting device 32g is composed of, for example, a hydraulic or pneumatic cylinder, with a fixed part such as a cylinder tube fixed to the frame 32b and an operating part such as a rod attached to the drive unit. Therefore, by operating this lifting device 32g, as shown in Figure 8(b), the drive unit is separated from the roller conveyor 32a, and the power of the drive belt 32c is no longer transmitted to the roller conveyor 32a. As a result, the roller conveyor 32a can rotate freely, and multiple sanitary paper bundles B can be kept on the roller conveyor 32a.

[0053] In the embodiment shown in Figure 9, the storage mechanism 30 is realized by controlling the starting and stopping of multiple conveyors. In particular, this embodiment in Figure 9 assumes that the sanitary paper bundles B are distributed one by one to the transport path with intervals between them by the sorting device 3. In the example shown in Figure 9, one transport path after the sorting device 3 is formed by the first conveyor 13(a)(1) to the sixth conveyor 13(a)(6) in order from the upstream side. Note that the number of these conveyors can be increased or decreased. Each conveyor 13(a)(1) to 13(a)(6) has a transport length sufficient to carry one sanitary paper bundle B. During normal operation as shown in Figure 9(a), all of these conveyors 13(a)(1) to 13(a)(6) are in operation and transport the sanitary paper bundles B downstream as usual. Furthermore, during normal operation, the interval at which the sanitary paper bundles B are distributed from the sorting device 3 to the transport path is greater than or equal to the transport length of a single conveyor.

[0054] On the other hand, as shown in Figure 9(b), if it becomes necessary to retain the sanitary paper bundles B due to a malfunction in the packaging machine 4, first, when one sanitary paper bundle B is placed on the downstream sixth conveyor 13(a)(6), the sixth conveyor 13(a)(6) is stopped and the sanitary paper bundle B is left on it. The other first conveyors 13(a)(1) through fifth conveyors 13(a)(5) continue to operate. Next, as shown in Figure 9(c), when another sanitary paper bundle B is placed on the fifth conveyor 13(a)(5), the fifth conveyor 13(a)(5) is stopped and the sanitary paper bundle B is left on it. The other first conveyors 13(a)(1) through fourth conveyors 13(a)(4) continue to operate. Next, as shown in Figure 9(d), when yet another bundle of sanitary paper B is placed on the fourth conveyor 13(a)(4), the fourth conveyor 13(a)(4) is stopped, and the bundle of sanitary paper B is left on it. By repeating this operation, bundles of sanitary paper B can be stored closely together on each conveyor. In the example shown in Figure 9, a maximum of six bundles of sanitary paper B, the same number as the conveyors, can be stored. The sorting device 3 will continue to supply bundles of sanitary paper B along the transport path for a predetermined period even after a problem occurs, but by storing the bundles of sanitary paper B closely together in this way, it is possible to gain time until the supply amount of sanitary paper B and the operation of the sorting device 3 are adjusted. It is also possible to stock multiple bundles of sanitary paper B on a single conveyor by controlling the starting and stopping of each conveyor.

[0055] In the embodiment shown in Figure 10, similar to the embodiment in Figure 9, the storage mechanism 30 is realized by controlling the starting and stopping of multiple conveyors. However, the embodiment in Figure 10 assumes that the sorting device 3 sorts the sanitary paper bundles B into groups of multiple bundles (e.g., 4 bundles), and that a predetermined interval is formed between the groups of multiple sanitary paper bundles B. In the example shown in Figure 10, one transport path after the sorting device 3 is formed by the first conveyor 13(a)(1) to the fourth conveyor 13(a)(4) in order from the upstream side. The number of these conveyors can be increased or decreased. Each conveyor 13(a)(1) to 13(a)(4) has a transport length sufficient to carry multiple (e.g., 4) sanitary paper bundles B simultaneously. During normal operation as shown in Figure 10(a), all of these conveyors 13(a)(1) to 13(a)(4) are in operation and transport the sanitary paper bundles B downstream as usual. Furthermore, during normal operation, the spacing between groups of sanitary paper bundles B as they are distributed from the sorting device 3 to the transport path is greater than or equal to the transport length of a single conveyor.

[0056] On the other hand, as shown in Figure 10(b), if it becomes necessary to retain the sanitary paper bundles B due to a malfunction in the packaging machine 4, first, when all four bundles of sanitary paper bundles B are on the downstream fourth conveyor 13(a)(4), the fourth conveyor 13(a)(4) is stopped and the bundles of sanitary paper bundles B are left on it. The other first conveyors 13(a)(1) through the third conveyors 13(a)(3) continue to operate. Next, as shown in Figure 10(c), when all another bundle of sanitary paper bundles B are on the third conveyor 13(a)(3), the third conveyor 13(a)(3) is stopped and the bundles of sanitary paper bundles B are left on it. The other first conveyors 13(a)(1) and the second conveyors 13(a)(2) continue to operate. Next, as shown in Figure 10(d), when another group of sanitary paper bundles B is placed on the second conveyor 13(a)(2), the second conveyor 13(a)(2) is stopped, and the group of sanitary paper bundles B is left on it. By repeating this operation, groups of sanitary paper bundles B can be stored closely together on each conveyor. In the example shown in Figure 10, a maximum of four groups of sanitary paper bundles B, the same as the number of conveyors, can be stored.

[0057] Next, in the embodiment shown in Figure 11, the retention mechanism 30 is realized by slowing down the sanitary paper bundles B on the transport path and narrowing the spacing between the sanitary paper bundles B. In the embodiment shown in Figure 11, one transport path after the sorting device 3 is composed of multiple conveyors. In the example in Figure 11, the first conveyor 13(a)(1) and the second conveyor 13(a)(2) are arranged in order from the upstream side. Each conveyor 13(a)(1) and 13(a)(2) has a transport length sufficient to carry multiple (for example, six or more) sanitary paper bundles B simultaneously. During normal operation as shown in Figure 11(a), all of these conveyors 13(a)(1) and 13(a)(2) are operating at normal speeds and transport the sanitary paper bundles B downstream.

[0058] On the other hand, as shown in Figure 11(b), if it becomes necessary to hold back the sanitary paper bundles B due to a malfunction in the packaging machine 4, the second conveyor 13(a)(2) is operated at a lower speed than the first conveyor 13(a)(1). As a result, the difference in speed between the first conveyor 13(a)(1) and the second conveyor 13(a)(2) causes the spacing between the sanitary paper bundles B to decrease as they move from the first conveyor 13(a)(1) to the second conveyor 13(a)(2). In other words, the spacing between the sanitary paper bundles B when they are on the second conveyor 13(a)(2) becomes narrower than the spacing between them when they are on the first conveyor 13(a). In this embodiment, since the conveyors 13(a)(1) and 13(a)(2) that constitute the retention mechanism do not stop, the sanitary paper bundles B will be transported downstream over time. However, by, for example, setting the operating speed of the downstream second conveyor 13(a)(2) to a sufficiently low speed, it is possible to gain time to adjust the supply amount of sanitary paper bundles B and the operation of the distribution device 3. It is preferable to use the retention mechanism 30 shown in Figure 11 as an auxiliary mechanism. In other words, since it is difficult to retain the sanitary paper bundles B for a long time using only the retention mechanism 30 shown in Figure 11, it is preferable to combine the retention mechanism 30 shown in Figure 11 with a retention mechanism according to another embodiment described in Figures 7 to 10 on the downstream side.

[0059] Figures 12 and 13 show an example of the spacing adjustment mechanism 40 (see Figure 5) described above. In the example shown in Figure 12, in each transport path, a waiting zone 40(a), a receiving zone 40(b), and an adjustment zone 40(c) are provided in this order downstream of the individual conveyors 13(a) to (c) having the aforementioned retention mechanism, as the spacing adjustment mechanism 40. Each zone is formed by one or more conveyors. In the example shown in Figure 12, the waiting zone 40(a) and the receiving zone 40(b) are each composed of one conveyor, and the adjustment zone 40(c) is composed of three conveyors. Each conveyor constituting each zone can be individually controlled to either proceed (transporting the sanitary paper bundles B downstream) or stop (holding the sanitary paper bundles B on the conveyor). In this example, it is assumed that each group of sanitary paper bundles B that are continuously distributed along the same path in the sorting process contains four sanitary paper bundles B. Thus, the number of conveyors constituting the adjustment zone 40(c) can be one less than the number of sanitary paper bundles B belonging to one group, but a larger number is also acceptable.

[0060] Figure 13 shows an example of the operation of a waiting zone 40(a), receiving zone 40(b), and adjustment zone 40(c) that form a single path. In this path, the operations in the order of Figure 13(a), (b), (c), and (d) are repeated. Also in Figure 13, the first group containing four sanitary paper bundles B is indicated by the symbol G1, the next group (also containing four sanitary paper bundles B) that is transported at a predetermined interval from the first group G1 is indicated by the symbol G1', and the next group (also containing four sanitary paper bundles B) is indicated by the symbol G1''.

[0061] First, as shown in Figure 13(a), the aforementioned group G1 passes through the waiting zone 40(a) and the receiving zone 40(b) and enters the adjustment zone 40(c). This adjustment zone 40(c) supplies the sanitary paper bundles B to the packaging machine one by one, in accordance with the processing capacity (packaging speed) of the packaging machine. Specifically, the adjustment zone 40(c) consists of three conveyors, and the receiving zone 40(b) consists of one conveyor, so the sum of the number of conveyors in these zones corresponds to the number of sanitary paper bundles B included in the aforementioned group G1. By controlling the progress and stopping of the four conveyors that make up these zones, the sanitary paper bundles B are temporarily held one by one, and then sent downstream one by one in accordance with the processing capacity of the packaging machine, the sanitary paper bundles B can be supplied to the packaging machine one by one.

[0062] On the other hand, as shown in Figure 13(a), in the waiting zone 40(a), the conveyor is stopped and the four sanitary paper bundles B included in the later group G1' are held on this conveyor. The conveyor in the waiting zone 40(a) keeps the sanitary paper bundles B included in the earlier group G1 waiting on the conveyor until they have all passed through the receiving zone 40(b). In the state shown in Figure 13(a), the last sanitary paper bundle B included in the earlier group G1 is still in the receiving zone 40(b), so the later group G1' is kept waiting in the waiting zone 40(a).

[0063] Next, as shown in Figure 13(b), once all of the sanitary paper bundles B included in the aforementioned group G1 have passed through the receiving zone 40(b), the subsequent group G1', which had been waiting in the waiting zone 40(a), is sent from the waiting zone 40(a) to the receiving zone 40(b). At this time, the supply of sanitary paper bundles B to the packaging machine continues in the adjustment zone 40(c).

[0064] Next, as shown in Figure 13(c), the receiving zone 40(b) holds the sanitary paper bundles B in the later group G1' on the conveyor that makes up the receiving zone 40(b) until all of them have been received. In other words, no sanitary paper bundles B are sent from the receiving zone 40(b) to the adjustment zone 40(c) until all of the sanitary paper bundles B in the later group G1' have been transferred from the waiting zone 40(a) to the receiving zone 40(b). In this way, all of the sanitary paper bundles B in the later group G1' temporarily wait on the conveyor that makes up the receiving zone 40(b). During this time, however, the supply of sanitary paper bundles B to the packaging machine continues in the adjustment zone 40(c). Some of the conveyors that make up the adjustment zone 40(c) may not hold the sanitary paper bundles B, but this does not pose any particular problem.

[0065] Next, as shown in Figure 13(d), after the sanitary paper bundles B of the later group G1' are gathered in the receiving zone 40(b), the distribution of the sanitary paper bundles B from the receiving zone 40(b) to the adjustment zone 40(c) begins. After being distributed to the adjustment zone 40(c), group G1' will be supplied to the packaging machine following the earlier group G1. At this time, there are no sanitary paper bundles B remaining in the waiting zone 40(a), so the sanitary paper bundles B included in the later group G1'' are supplied to this waiting zone 40(a) and made to wait on the conveyor that makes up this waiting zone 40(a). The even later group G1'' waiting in the waiting zone 40(a) will wait until the receiving zone 40(b) is empty, as shown in Figures 13(a) and 13(b), and once the receiving zone 40(b) is empty, distribution to the receiving zone 40(b) will begin.

[0066] In this way, the processes shown in Figures 13(a) to (d) are repeated. This allows the packaging machine to supply one bundle of sanitary paper B at a time according to its processing capacity. Furthermore, since the packaging machine is supplied with sanitary paper B continuously at basically uniform time intervals, the packaging machine can be utilized efficiently.

[0067] Furthermore, Figure 14 shows another embodiment of the sorting device 20. For example, in the embodiment of the sorting device 20 described with reference to Figures 2 and 4, multiple (e.g., 4) bundles of sanitary paper B were sorted into their respective transport paths (individual conveyors 13(a) to (c)). However, in the embodiment of the sorting device 20 shown in Figure 14, it becomes easy to sort each bundle of sanitary paper B individually into its respective transport path (individual conveyors 13(a) to (c)). For example, as shown in Figure 14, multiple extrusion devices 20(a) to (c) that function as the sorting device 20 are arranged on the main conveyor 11, and individual conveyors 13(a) to (c) are arranged at the extrusion destinations of these extrusion devices 20(a) to (c). By operating these extrusion devices 20(a) to (c) in sequence, one bundle of sanitary paper B can be sorted from the main conveyor 11 to each individual conveyor 13(a) to (c). For these individual conveyors 13(a) to (c), it is preferable to use flexible plastic chain conveyors that can form curves. Furthermore, one packaging machine 4 is positioned downstream of each individual conveyor 13(a) to (c), via the aforementioned conveyor with a retention mechanism. It is also possible to place further packaging machines downstream of the main conveyor, but it can also be used as a discharge line as shown in Figure 4(d).

[0068] In this specification, embodiments of the present invention have been described with reference to the drawings in order to express the content of the present invention. However, the present invention is not limited to the above embodiments, and includes modifications and improvements that are obvious to those skilled in the art based on the matters described in this specification. [Explanation of Symbols]

[0069] 11...Main conveyor 12...Wide conveyor 13... Individual conveyor belt 14... Stopper 20... Distribution conveyor 21... Pivot point 22...Sensor 30...Retention mechanism 31... Accumulator conveyor 31a... Plate conveyor belt 31b...Drive pulley 31c...Driven pulley 31d...Free roller 31e...Conveyor surface 32...Roller conveyor with drive unit 32a...Roller conveyor 32b...frame 32c...drive belt 32d…Drive pulley 32e…Driven pulley 32f...Drive unit 32g...Lifting unit 40...Interval adjustment mechanism 40(a)...Standby zone 40(b)... Acceptance Zone 40(c)... Adjustment Zone P…Sanitary paper B…Sanitary paper stack

Claims

1. A method for manufacturing a sanitary paper bundle product, A process of distributing multiple bundles of sanitary paper that have been transported along a certain transport route to multiple individual transport routes using a sorting device, A step of transporting the sanitary paper bundles at intervals using the aforementioned multiple individual transport paths, The process includes packaging the bundles of sanitary paper that have been transported along the individual transport route using a packaging machine, Each of the individual transport paths includes a retention mechanism that can accept a certain amount of the sanitary paper bundles distributed from the sorting device into the individual transport path, while stopping the discharge of the sanitary paper bundles downstream of that individual transport path and narrowing the spacing between the sanitary paper bundles being transported in that individual transport path. If, among the aforementioned multiple individual transport routes, a route where the transport of the sanitary paper bundles to the downstream side is prohibited due to circumstances including trouble or maintenance work on the downstream side is designated as an unacceptable route, and a route where the transport of the sanitary paper bundles to the downstream side is permitted even after the occurrence of such circumstances is designated as an acceptable route, For at least a certain period following the occurrence of the aforementioned circumstances, the sorting device will continue to sort the sanitary paper bundles into the unacceptable route and the acceptable route. In the unacceptable route, the retention mechanism will stop transporting the sanitary paper bundles downstream, while simultaneously narrowing the spacing between the transported sanitary paper bundles and accepting the sanitary paper bundles sorted from the sorting device. A method for manufacturing sanitary paper bundle products.

2. After a certain period has elapsed since the occurrence of the aforementioned circumstances, the sorting device will stop distributing the sanitary paper bundles to the unacceptable routes and will instead distribute the sanitary paper bundles only to the acceptable routes. A method for manufacturing a sanitary paper bundle product according to claim 1.

3. The retention mechanism includes an accumulation conveyor having a conveying section on the conveying surface of the sanitary paper bundle that conveys the sanitary paper bundle by frictional force generated between the conveying section and the lower surface of the sanitary paper bundle, and an idle section in which a contact element that contacts the lower surface of the sanitary paper bundle rotates freely. A method for manufacturing a sanitary paper bundle product according to claim 1 or claim 2.

4. The aforementioned retention mechanism is, A roller conveyor having multiple rollers that can rotate freely, A drive device that rotates the roller in a certain direction, The device includes a switching mechanism that switches between a driven state in which the drive device rotates the roller and an idle state in which the rotation of the roller by the drive device is stopped and the roller is able to rotate freely. When the aforementioned circumstances occur, the switching device constituting the retention mechanism of the unacceptable path switches from the driven state to the idle state. A method for manufacturing a sanitary paper bundle product according to claim 1.

5. The aforementioned storage mechanism includes a plurality of conveyors, each capable of individually controlling their start and stop. A method for manufacturing a sanitary paper bundle product according to claim 1.

6. The conveyor has a conveying surface of a length that allows multiple bundles of sanitary paper to be transported simultaneously. A method for manufacturing a sanitary paper bundle product according to claim 5.

7. A manufacturing apparatus for sanitary paper bundle products, A sorting device that distributes multiple bundles of sanitary paper transported along a certain transport route to multiple individual transport routes, Multiple transport devices that transport the sanitary paper bundles at intervals along the multiple individual transport paths, The system includes a packaging machine for packaging the bundles of sanitary paper that have been transported along the individual transport routes, Each of the transport devices has a retention mechanism that can accept a certain amount of the sanitary paper bundles distributed from the sorting device into its individual transport path, while stopping the discharge of the sanitary paper bundles downstream of its individual transport path and narrowing the spacing between the sanitary paper bundles being transported along that individual transport path. If, among the aforementioned multiple individual transport routes, a route where the transport of the sanitary paper bundles to the downstream side is prohibited due to circumstances including trouble or maintenance work on the downstream side is designated as an unacceptable route, and a route where the transport of the sanitary paper bundles to the downstream side is permitted even after the occurrence of such circumstances is designated as an acceptable route, For at least a certain period following the occurrence of the aforementioned circumstances, the sorting device will continue to sort the sanitary paper bundles into the unacceptable route and the acceptable route. In the unacceptable route, the retention mechanism will stop transporting the sanitary paper bundles downstream, while simultaneously narrowing the spacing between the transported sanitary paper bundles and accepting the sanitary paper bundles sorted from the sorting device. Manufacturing equipment for sanitary paper bundle products.

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