Control method, manufacturing method of paper-made material, and manufacturing method of gear

Abstract

To appropriately perform dehydration under pressure, while smoothly operating a cylinder.SOLUTION: A second upper die 13 is die-opened / closed and die-fastened for a lower die 11. Pressure relating to expansion / contraction of an outer ring cylinder 64 is controlled, according to at least one of a pressing state of an outer ring 16 by an outer ring auxiliary cylinder 65 and a pressing state of the outer ring 16 by an outer ring auxiliary shaft.SELECTED DRAWING: Figure 8

Description

[Technical field]

[0001] The present disclosure relates to a control method, a method for manufacturing a paper article, and a method for manufacturing a gear. [Background technology]

[0002] In recent years, as part of environmentally friendly manufacturing, the use of plastic gears has been increasing instead of metal gears. Patent Document 1 discloses a papermaking machine that pressurizes and dehydrates a liquid (liquid raw material) containing fiber pieces to create a papermaking base material that will be the basis of a plastic gear. Patent Document 2 discloses a vertical injection molding machine in which a lower mold is placed on a turntable and an upper mold is raised and lowered to open, close, and clamp the mold. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2014-77541 A [Patent Document 2] Patent Publication No. 2022-24412 Summary of the Invention [Problem to be solved by the invention]

[0004] Here, when the liquid raw material is pressurized and dehydrated by the dehydration device as described above, the liquid raw material spreads laterally due to the pressure of the mold, and the liquid raw material spread laterally may affect the operation of the cylinder of the outer ring arranged to surround the mold. Furthermore, performing pressurized dehydration under such conditions may increase the load on the cylinder.

[0005] The present disclosure has been made in consideration of the above-mentioned circumstances, and has an object to appropriately perform pressurized dehydration while reducing the load on the cylinder. [Means for solving the problem]

[0006] A control method according to one aspect of the present disclosure is a dehydration apparatus that fills a mold with liquid raw material and dehydrates it under pressure, the control method including a lower mold, an outer ring arranged to surround the lower mold, an outer ring cylinder configured to be extendable and to raise and lower the outer ring, an upper mold that opens and closes and clamps against the lower mold by raising and lowering above the lower mold, an outer ring auxiliary cylinder configured to be extendable and to press the outer ring downward by extending, and an outer ring auxiliary shaft that presses the outer ring downward by contacting the lower mold, the control method including opening and closing, and clamping the upper mold against the lower mold, and controlling the pressure related to the extension and contraction of the outer ring cylinder in accordance with at least one of the state of pressing the outer ring by the outer ring auxiliary cylinder and the state of pressing the outer ring by the outer ring auxiliary shaft. Effect of the Invention

[0007] According to the present disclosure, it is possible to appropriately perform pressurized dehydration while reducing the load on the cylinder. [Brief description of the drawings]

[0008] [Figure 1] FIG. [Diagram 2] FIG. [Diagram 3] 13 is a schematic diagram showing a drainage mechanism that drains liquid through a drainage passage. FIG. [Figure 4] FIG. 2 is a hardware block diagram of the papermaking machine. [Diagram 5] 1 is a flow chart of a fiber filling process. [Figure 6] 1 is a flowchart of a pressurized dehydration process. [Figure 7] FIG. 2 is a diagram illustrating a pressurized dehydration process. [Figure 8] FIG. 2 is a diagram illustrating a pressurized dehydration process. [Figure 9] FIG. 2 is a diagram illustrating a pressurized dehydration process. [Figure 10] FIG. 2 is a diagram illustrating a pressurized dehydration process. [Figure 11] FIG. 2 is a diagram illustrating a pressurized dehydration process. [Figure 12]FIG. 2 is a diagram illustrating a pressurized dehydration process. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, a method for controlling the papermaking machine 1 (dewatering device) according to the present embodiment will be described with reference to the drawings. Note that the present embodiment described below is an example of how the present disclosure is embodied, and does not limit the scope of the present disclosure to the scope of the embodiment. Therefore, the present disclosure can be implemented by adding various modifications to the embodiment.

[0010] [Configuration of papermaking machine 1] The configuration of a papermaking machine 1, which is an example of a dewatering device, will be described with reference to Figs. 1 and 2. Fig. 1 is a side view of the papermaking machine 1. Fig. 2 is a plan view of the papermaking machine 1. Figs. 1 and 2 are both schematic views, and the configuration of the papermaking machine 1 is illustrated in a simplified manner. Therefore, the shapes of the components shown in Figs. 1 and 2 may differ from the actual shapes. For example, Figs. 1 and 2 omit the illustration of components such as an outer cylinder 64, an outer auxiliary cylinder 65, and an outer auxiliary shaft 80 (see Fig. 7, etc.), which will be described later. The papermaking machine 1 is a device that produces a papermaking base material 3 (paper product), which is a molded product, by filling a mold with a slurry 2 (liquid raw material) and dehydrating it under pressure.

[0011] The slurry 2 is a liquid containing fiber pieces. More specifically, the slurry 2 is a mixture of water, fiber pieces (e.g., aramid fiber), additives such as a fixing agent, and resin (e.g., high-strength, high-heat-resistant polyaminoamide resin) in a predetermined ratio. However, the content ratio of the fiber pieces in the slurry 2 is not always constant and may vary slightly.

[0012] The papermaking substrate 3 is a cylindrical member that serves as the base for a resin gear. More specifically, a resin gear is manufactured by forming teeth on the outer peripheral surface of the cylindrical papermaking substrate 3 manufactured by the papermaking machine 1 (a process for obtaining a gear). The resin gear is used, for example, in the drive system of an automobile. Compared to metal gears, the resin gear manufactured from the papermaking substrate 3 reduces meshing noise and teeth rattle noise and can be made lighter. However, the product manufactured from the papermaking substrate 3 is not limited to gears, and the use of the gear is not limited to the drive system of an automobile.

[0013] As shown in Figures 1 and 2, the mold of the papermaking machine 1 is composed of two lower molds 11, a first upper mold 12, and a second upper mold 13. The lower mold 11 is supported by a support block 14. An insert 15 is housed within the lower mold 11. Furthermore, the lower mold 11 is held by an outer ring 16, and the second upper mold 13 is held by an outer ring 17. However, the number of lower molds 11 may be one.

[0014] The two lower dies 11 have the same shape. The lower dies 11 have a cylindrical outer shape. The diameter of the lower dies 11 corresponds to the outer dimensions of the papermaking substrate 3. The lower dies 11 are formed with a drainage passage 11a that penetrates in the vertical direction. The lower dies 11 are fixed to a support block 14. An insert 15 is placed on the upper surface of the lower dies 11. The lower dies 11 are disposed inside an outer ring 16.

[0015] The support block 14 supports the lower die 11 and the outer ring 16. More specifically, the lower die 11 is fixed to the upper surface of the support block 14. The support block 14 also supports the outer ring 16 so that it can be raised and lowered. The support block 14 also has a drainage passage 14a formed therein, which is connected to the drainage passage 11a of the lower die 11. The drainage passage 14a extends in the vertical direction as shown in FIG. 1, and then bends in the radial direction (horizontal direction) of the rotary table 21 as shown in FIG. 3. The drainage passage 14a is connected to drainage pumps 43a, 43b via connection parts 41a, 41b, which will be described later with reference to FIG. 3. Furthermore, the support block 14 has a ring-shaped recess 14b recessed downward from the upper surface.

[0016] The insert 15 is detachably placed on the upper surface of the lower mold 11. The insert 15 has a ring-shaped (cylindrical) outer shape. The outer dimensions of the insert 15 are smaller than the outer dimensions of the lower mold 11. The insert 15 is a metal part that constitutes part of the inner circumference of the papermaking substrate 3 (i.e., a resin gear).

[0017] The outer ring 16 has a tubular (typically cylindrical) outer shape. The outer ring 16 is disposed so as to surround the lower die 11. The outer ring 16 is supported from below by an outer ring cylinder 64 (see FIG. 7, etc.). The outer ring 16 is configured to be able to rise and fall independently of the lower die 11 by the extension and contraction of the outer ring cylinder 64.

[0018] The outer ring cylinder 64 (see FIG. 7, etc.) is, for example, an air cylinder that expands and contracts by supplying and discharging compressed air. As shown in FIG. 7, etc., the outer ring cylinder 64 is disposed between the support block 14 and the outer ring 16. In other words, the outer ring cylinder 64 supports the outer ring 16. Furthermore, the outer ring cylinder 64 raises and lowers the outer ring 16 by expanding and contracting.

[0019] More specifically, the outer ring 16 is raised to the upper limit (forward limit) by extending the outer ring cylinder 64 to the maximum with the rising pressure P1. The outer ring 16 is maintained at the upper limit by applying the rising maintenance pressure P2 to the outer ring cylinder 64 extended to the maximum. As shown in FIG. 8(A), the outer ring 16 is set to a support pressure P3 (reference pressure) in the outer ring cylinder 64 while waiting for the second upper die 13 to descend. As shown in FIG. 9(A), when the outer ring 16 is pressed by the outer ring auxiliary cylinder 65 and the outer ring auxiliary shaft 80, a low pressure P10 lower than the support pressure P3 is set in the outer ring cylinder 64, and the outer ring 16 is pressed from above by the outer ring auxiliary cylinder 65, so that the outer ring 16 descends to an arbitrary position between the upper limit and the lower limit. 10(A), the outer ring 16 is lowered to the lower limit by contracting the outer ring cylinder 64 with the lowering pressure P11 after the pressurized dehydration is completed. The above-mentioned pressures have at least the relationship P11>P3>P10. Also, P1=P2=P3 may be satisfied, or P1=P2>P3 may be satisfied, or P1>P2>P3 may be satisfied.

[0020] The first upper die 12 is disposed above the lower die 11 and the outer ring 16. The first upper die 12 has a cylindrical outer shape with an open lower surface and a closed upper surface. The inner diameter of the first upper die 12 corresponds to the inner diameter of the outer ring 16. Furthermore, a supply port 12a through which the slurry 2 is supplied from a supply device (not shown) is provided on the upper surface of the first upper die 12. The first upper die 12 is opened, closed, and clamped relative to the lower die 11 (more specifically, the outer ring 16) by transmitting the driving force of a first die opening / closing motor 62 (see FIG. 4).

[0021] The second upper die 13 is disposed above the lower die 11. The second upper die 13 has a ring-shaped outer shape. The inner diameter of the second upper die 13 corresponds to the outer diameter of the insert 15. The outer diameter of the second upper die 13 corresponds to the inner diameter of the outer ring 16. The second upper die 13 is fixed to the inside of the outer ring 17.

[0022] The outer ring 17 is disposed above the outer ring 16. The outer ring 17 has a tubular (typically cylindrical) outer shape with an open lower surface and a closed upper surface. The inner diameter of the outer ring 17 corresponds to the outer diameter of the second upper mold 13 and the inner diameter of the outer ring 16. The outer ring 17 is disposed so as to surround the second upper mold 13. The second upper mold 13 and the outer ring 17 are raised and lowered together by transmitting the driving force of a second mold opening / closing motor 63 (see FIG. 4 ), and are opened / closed and clamped relative to the lower mold 11 and the outer ring 16.

[0023] In the example of Fig. 1, one lower die 11 is supported on the support block 14, but the support block 14 may support a plurality of (e.g., four) lower dies 11 collectively. In other words, in the example of Fig. 1, one lower die 11 is arranged in the outer ring 16, but the outer ring 16 may hold a plurality of (e.g., four) lower dies 11 collectively. In addition, the number of first upper dies 12 corresponds to the number of lower dies 11 held by the outer ring 16. Similarly, the number of second upper dies 13 held collectively by the outer ring 17 corresponds to the number of lower dies 11 held by the outer ring 16.

[0024] 1 and 2, the papermaking machine 1 includes a frame 20, a rotary table 21 (table), a first movable die plate 22, and a second movable die plate 23. The frame 20 supports the rotary table 21, the first movable die plate 22, and the second movable die plate 23, as well as other components of the papermaking machine 1.

[0025] The rotary table 21 has a disk-shaped outer shape. The rotary table 21 is rotatably supported by the frame 20 via a rotary shaft 24 extending in the vertical direction. The rotary table 21 is formed with only the minimum number of taps (through holes). The taps provided on the rotary table 21 are closed with bolt caps.

[0026] A support block 14 is placed on the upper surface of the turntable 21. The two support blocks 14 according to this embodiment are arranged at an interval of 180° in the circumferential direction of the turntable 21 (in other words, arranged on opposite sides of the rotation shaft 24). Furthermore, the turntable 21 rotates around the rotation shaft 24 by the transmission of the driving force of a table rotation motor 61 (see FIG. 4).

[0027] More specifically, the rotating table 21 is configured to be movable (rotatable) so that the lower mold 11 placed via the support block 14 faces the first upper mold 12 or the second upper mold 13. In this embodiment, when one of the two lower molds 11 faces the first upper mold 12, the other lower mold 11 faces the second upper mold 13.

[0028] 2 and other figures, the first movable die plate 22 is supported by the frame 20 above the rotary table 21. The first upper die 12 is fixed to the lower surface of the first movable die plate 22. The first movable die plate 22 opens, closes, and clamps the first upper die 12 relative to the lower die 11 by transmitting the driving force of a first die opening / closing motor 62 through a toggle link mechanism (not shown).

[0029] More specifically, as the first die opening / closing motor 62 rotates in the first direction, the first movable die plate 22 descends together with the first upper die 12. As a result, as shown in Fig. 1(B), the lower end of the first upper die 12 comes into contact with the upper end of the outer ring 16, and a cavity (internal space) is formed between the lower die 11, the first upper die 12, and the outer ring 16 (i.e., the die is closed). Then, when further downward pressure is applied to the first movable die plate 22, the lower die 11 (outer ring 16) and the first upper die 12 are clamped together.

[0030] Then, with the lower mold 11 (outer ring 16) and the first upper mold 12 clamped together, the slurry 2 is supplied from the supply device through the supply port 12a, so that the inside of the lower mold 11 (more specifically, the space surrounded by the upper surface of the lower mold 11, the outer peripheral surface of the insert 15, and the inner peripheral surface of the outer ring 16) is filled with the slurry 2. With the lower mold 11 (outer ring 16) and the first upper mold 12 clamped together, the drainage pump 43a is driven, so that the liquid contained in the slurry 2 filled inside the lower mold 11 is drained (primary dehydration) through the drainage passages 11a, 14a and the connection part 41a at the first connection position.

[0031] On the other hand, when the first die opening / closing motor 62 rotates in a second direction opposite to the first direction, the first movable die plate 22 rises together with the first upper die 12. As a result, the lower die 11 (outer ring 16) and the first upper die 12 are opened as shown in FIG.

[0032] As shown in Fig. 2 and other figures, the second movable die plate 23 is supported by the frame 20 above the rotary table 21. The second upper die 13 and the outer wheel 17 are fixed to the lower surface of the second movable die plate 23. The second movable die plate 23 also supports a pair of outer wheel auxiliary cylinders 65 (see Fig. 7(A) and other figures). The second movable die plate 23 opens, closes, and clamps the second upper die 13 relative to the lower die 11 by transmitting the driving force of a second die opening / closing motor 63 through a toggle link mechanism (not shown).

[0033] More specifically, the second movable die plate 23 is lowered together with the second upper die 13, the outer ring 17, the outer ring auxiliary cylinder 65, and the outer ring auxiliary shaft 80 by rotating the second die opening / closing motor 63 in the first direction. As a result, the lower end of the outer ring 17 comes into contact with the upper end of the outer ring 16, and a cavity (internal space) is formed between the lower die 11, the second upper die 13, the outer ring 16, and the outer ring 17 (i.e., the die is closed). Then, when a further downward pressure is applied to the second movable die plate 23, the outer ring 17 presses down the outer ring 16 against the support pressure P3 of the outer ring cylinder 64, as shown in FIG. 1(B). As a result, the second upper die 13 is lowered to a position where a part of the insert 15 enters the inside of the second upper die 13, and the lower die 11 (outer ring 16) and the second upper die 13 are clamped.

[0034] This causes the slurry 2 filled in the lower mold 11 to be pressurized and dehydrated. In addition, with the lower mold 11 and the second upper mold 13 clamped together, the drainage pump 43b is driven to drain the liquid contained in the slurry 2 filled in the lower mold 11 through the drainage passages 11a and 14a (secondary dehydration). As a result, the slurry 2 in the space surrounded by the upper surface of the lower mold 11, the lower surface of the second upper mold 13, the outer peripheral surface of the insert 15, and the inner peripheral surface of the outer ring 16 is compressed to become the papermaking substrate 3.

[0035] On the other hand, when the second die opening / closing motor 63 rotates in a second direction opposite to the first direction, the second movable die plate 23 rises together with the second upper die 13, the outer ring 17, the outer ring auxiliary cylinder 65, and the outer ring auxiliary shaft 80. This causes the lower die 11 and the second upper die 13 to be opened, as shown in FIG.

[0036] The papermaking substrate 3 in the lower mold 11 is then removed from the lower mold 11 together with the insert 15 by a robot arm (not shown). The papermaking substrate 3 removed from the lower mold 11 is then dried in an oven, and teeth are formed on the outer circumferential surface to form a resin gear. A new insert 15 is then inserted by the robot arm into the lower mold 11 from which the papermaking substrate 3 was removed.

[0037] The outer wheel auxiliary cylinder 65 (see FIG. 7, etc.) is, for example, an air cylinder that expands and contracts by supplying and discharging compressed air, and presses the outer wheel 16 downward by expanding. As shown in FIG. 7, etc., the outer wheel auxiliary cylinder 65 is extended downward from the second movable die plate 23. As shown in FIG. 8(B), the outer wheel auxiliary cylinder 65 presses the outer wheel 16 from above by the second movable die plate 23 descending. As shown in FIG. 8(B), the outer wheel auxiliary cylinder 65 may abut against the outer wheel 16 from above, thereby lowering the outer wheel 16 to its lowering limit against the outer wheel cylinder 64 of the support pressure P3. The outer wheel auxiliary cylinder 65 may release pressure when pressing the outer wheel 16 (see FIG. 9(A), details will be described later). Furthermore, the outer wheel auxiliary cylinder 65 may be set with a pressure in the expanding direction in order to assist the outer wheel 16 in moving downward when the pressurized dehydration is completed (see FIG. 10(A) , details will be described later). After the outer wheel 16 has descended to its lowering limit, the outer wheel auxiliary cylinder 65 contracts with the increasing pressure P20, thereby moving backward (see FIG. 11(B) , details will be described later).

[0038] The outer wheel auxiliary shaft 80 (see FIG. 7, etc.) is a shaft that presses the outer wheel 16 downward by contacting the lower die 11. The outer wheel auxiliary shaft 80 is held by the second upper die 13, and extends in the vertical direction, similar to the outer wheel auxiliary cylinder 65, etc.

[0039] [Configuration of drainage mechanisms 40a, 40b] Fig. 3 is a schematic diagram showing drainage mechanisms 40a, 40b that drain liquid through drainage passages 11a, 14a. As shown in Fig. 3, the papermaking machine 1 is equipped with drainage mechanisms 40a, 40b. The drainage mechanisms 40a, 40b are supported by the frame 20 on the radial outside of the turntable 21. The drainage mechanisms 40a, 40b are also arranged at positions that can face the support block 14 in the horizontal direction. The drainage mechanisms 40a, 40b are also arranged at positions spaced apart (at 180° intervals) in the circumferential direction of the turntable 21.

[0040] The drainage mechanism 40a drains liquid from the support block 14 supporting the lower die 11 facing the first upper die 12. The drainage mechanism 40a includes a connection part 41a (first connection part), a drainage cylinder 42a, and a drainage pump 43a. The drainage mechanism 40b drains liquid from the support block 14 supporting the lower die 11 facing the second upper die 13. The drainage mechanism 40b includes a connection part 41b (second connection part), a drainage cylinder 42b, and a drainage pump 43b.

[0041] The connection part 41a is supported by the frame 20 so as to be movable in the radial direction of the turntable 21 between a first connection position shown in Fig. 3(B) and a first retracted position shown in Fig. 3(A). The drainage cylinder 42a is an actuator that moves the connection part 41a between the first connection position and the first retracted position. Specific examples of the actuator include an air cylinder, a hydraulic cylinder, and an electric motor. The drainage pump 43a sucks liquid from the support block 14 through the connection part 41a at the first connection position.

[0042] The first connection position is a position of the connection part 41a connected to the support block 14 supporting the lower die 11 facing the first upper die 12. A drainage passage is provided inside the connection part 41a, which connects the drainage passage 14a of the support block 14 and the drainage pump 43a when in the first connection position. The first retracted position is a position of the connection part 41a separated from the support block 14 and retracted to the outside of the turntable 21.

[0043] The connection part 41b is supported by the frame 20 so as to be movable in the radial direction of the turntable 21 between a second connection position shown in Fig. 3(B) and a second retracted position shown in Fig. 3(A). The drain cylinder 42b is an actuator that moves the connection part 41b between the second connection position and the second retracted position. Specific examples of the actuator include an air cylinder, a hydraulic cylinder, and an electric motor. The drain pump 43b sucks liquid from the support block 14 through the connection part 41b in the second connection position.

[0044] The second connection position is a position of the connection part 41b connected to the support block 14 supporting the lower die 11 facing the second upper die 13. A drainage passage is provided inside the connection part 41b, which connects the drainage passage 14a of the support block 14 and the drainage pump 43b when in the second connection position. The second retracted position is a position of the connection part 41b separated from the support block 14 and retracted to the outside of the turntable 21.

[0045] When the drain cylinders 42a, 42b are extended in a state where one of the two lower molds 11 (in other words, the two support blocks 14) faces the first upper mold 12 and the other faces the second upper mold 13, the connection part 41a moves to the first connection position and the connection part 41b moves to the second connection position. Then, the drain pumps 43a, 43b are driven to drain the liquid from the support block 14. Furthermore, when the drain cylinders 42a, 42b are contracted before the turntable 21 is rotated, the connection part 41a moves to the first retracted position and the connection part 41b moves to the second retracted position.

[0046] [Hardware configuration of papermaking machine 1] Fig. 4 is a hardware block diagram of the papermaking machine 1. As shown in Fig. 4, the papermaking machine 1 includes a control device 50. The control device 50 controls the overall operation of the papermaking machine 1. The control device 50 controls, for example, pressures related to the expansion and contraction of the outer cylinder 64 and the outer auxiliary cylinder 65.

[0047] The control device 50 includes, for example, a central processing unit (CPU) 51 which is a calculation means, a read only memory (ROM) 52 which stores various programs, and a random access memory (RAM) 53 which serves as a working area for the calculation means. The CPU 51 may read and execute the programs stored in the ROM 52 to realize each process described below.

[0048] However, the specific configuration of the control device 50 is not limited to this, and may be realized by hardware such as an application specific integrated circuit (ASIC) or a field programmable gate array (FPGA).

[0049] A display input device 54 is connected to the control device 50. The display input device 54 is a user interface including a display (display device) that displays various information to be notified to an operator, and an input device (for example, a button, a switch, a dial, or a touch panel superimposed on the display) that accepts operations by the operator.

[0050] For example, a mold clamping setting screen (not shown) is displayed on the display of the display input device 54. The mold clamping setting screen may be a screen for receiving input of a reference position [mm], a set speed [mm / s], a set pressure [MPa], and a set time [sec]. Then, the control device 50 may execute the pressurized dehydration process shown in FIG. 6 based on the reference position, set speed, set pressure, and set time inputted through the display input device 54. Note that at least one of the reference position, set speed, set pressure, and set time is inputted, and the others may be fixed values.

[0051] The reference position is a position of the second upper die 13 below the position where the outer ring 16 and the outer ring 17 come into contact with each other and above the position where the lower die 11 and the second upper die 13 complete the clamping. The reference position is specified, for example, by the difference from the clamping completion position (the position where the lower die 11 and the second upper die 13 approach each other to the maximum, which is the 0 mm position in FIG. 10). The set speed is the maximum value of the descending speed of the second upper die 13 from the time when the second upper die 13 reaches the reference position until the time when the set time has elapsed. The set pressure is the pressing force of the second upper die 13 against the lower die 11 from the time when the second upper die 13 reaches the reference position until the time when the set time has elapsed. The set time is the time for executing the torque control of the second die opening and closing motor 63 based on the set speed and the set pressure.

[0052] A cylinder pressure setting screen may be displayed on the display of the display input device 54. The cylinder pressure setting screen is a screen for receiving inputs of the rising pressure P1 [MPa], the rising maintaining pressure P2 [MPa], the support pressure P3 [MPa], the low pressure P10 [MPa], the decreasing pressure P11, the rising pressure P20 [MPa], and the like. The rising pressure P1, the rising maintaining pressure P2, the support pressure P3, the low pressure P10 [MPa], the decreasing pressure P11, and the rising pressure P20 are air pressures supplied to the outer cylinder 64 or the outer auxiliary cylinder 65. The control device 50 executes the pressurized dehydration process shown in FIG. 6 based on the rising pressure P1, the rising maintaining pressure P2, the support pressure P3, the low pressure P10 [MPa], the decreasing pressure P11, and the rising pressure P20 inputted through the display input device 54.

[0053] The control device 50 is also connected to a table rotation motor 61, a first mold opening / closing motor 62, a second mold opening / closing motor 63, an outer ring cylinder 64, an outer ring auxiliary cylinder 65, the drainage cylinders 42a, 42b, and the drainage pumps 43a, 43b. The control device 50 drives the table rotation motor 61, the first mold opening / closing motor 62, the second mold opening / closing motor 63, the outer ring cylinder 64, the outer ring auxiliary cylinder 65, the drainage cylinders 42a, 42b, and the drainage pumps 43a, 43b by outputting a control signal.

[0054] [Operation of papermaking machine 1] Next, the operation of the papermaking machine 1 will be described with reference to Figures 5 to 12. The control device 50 of the papermaking machine 1 executes a fiber filling process shown in Figure 5 and a pressurized dehydration process shown in Figure 6 in parallel. As a result, one of the two lower molds 11 is filled with slurry, and the papermaking base material 3 is produced in the other. The control device 50 then executes this process repeatedly, thereby efficiently manufacturing the papermaking base material 3.

[0055] [Fiber filling processing] Fig. 5 is a flow chart of the fiber filling process. The fiber filling process is a process in which the lower die 11 is filled with the slurry 2 and the liquid is discharged (primary dehydration) from the slurry 2 by the drainage mechanism 40a. At the start of the fiber filling process, the lower die 11 and the first upper die 12 are opened, the insert 15 is inserted into the lower die 11, and the outer ring 16 is at the upper limit, as shown in Fig. 1(A).

[0056] First, the control device 50 rotates the first mold opening / closing motor 62 in a first direction to close and clamp the first upper mold 12 relative to the lower mold 11 (S11). The fact that the lower mold 11 and the first upper mold 12 have been clamped can be detected by, for example, a sensor (not shown), a rotary encoder of the first mold opening / closing motor 62, or a combination of these.

[0057] Next, in response to completion of clamping of the lower mold 11 and the first upper mold 12 (S12: Yes), the control device 50 causes the supply device to supply the slurry 2 through the supply port 12a (S13). As a result, as shown in Fig. 1(B), a predetermined amount of the slurry 2 is filled inside the lower mold 11 (more specifically, the space surrounded by the upper surface of the lower mold 11, the outer peripheral surface of the insert 15, and the inner peripheral surface of the outer ring 16).

[0058] Next, the control device 50 extends the drain cylinder 42a to move the connection part 41a to the first connection position (i.e., connects the connection part 41a to the drain passage 14a of the support block 14). In addition, the control device 50 drives the drain pump 43a to drain the liquid from the slurry 2 filled in the lower mold 11 through the drain passages 11a, 14a and the connection part 41a (S14).

[0059] Next, the control device 50 waits to execute the process of step S16 until the pressurized dehydration process executed in parallel is completed (S15: No). The control device 50 also stops the drainage pump 43a when a predetermined time has elapsed since the drainage pump 43a started to be driven. Furthermore, after stopping the drainage pump 43a and before executing the process of step S16, the control device 50 contracts the drainage cylinder 42a to move the connection part 41a to the first retracted position.

[0060] Next, in response to the completion of the pressurized dehydration process executed in parallel (S15: Yes), the control device 50 rotates the table rotation motor 61 to rotate the turntable 21 by 180° (S16). As a result, the lower mold 11 filled with the slurry 2 in the fiber filling process faces the second upper mold 13, and the lower mold 11 from which the papermaking substrate 3 has been removed in the pressurized dehydration process faces the first upper mold 12.

[0061] [Pressure dehydration treatment] Fig. 6 is a flow chart of the pressurized dehydration process. Figs. 7 to 12 are diagrams for explaining the pressurized dehydration process.

[0062] The pressurized dehydration process is a process for discharging liquid from the slurry 2 filled in the lower die 11 by clamping the second upper die 13 to the lower die 11. At the start of the pressurized dehydration process, as shown in Fig. 7(A), the lower die 11 and the second upper die 13 are opened, the lower die 11 is filled with the slurry 2, the outer ring 16 is at its upper limit, and the outer ring auxiliary cylinder 65 is in a contracted state.

[0063] First, the control device 50 extends the outer wheel auxiliary cylinder 65 (S21). In this state, as shown in Fig. 7(B), the lower end of the outer wheel auxiliary cylinder 65 is disposed below the lower ends of the second upper die 13 and the outer wheel 17.

[0064] Next, as shown in Fig. 8(A), the control device 50 opens the outer ring auxiliary cylinder 65 to the atmosphere (depressurizes), applies a support pressure P3 (reference pressure) to the outer ring cylinder 64, and rotates the second die opening / closing motor 63 in the first direction (S22). As a result, the second movable die plate 23 descends together with the second upper die 13, the outer ring 17, the outer ring auxiliary cylinder 65, and the outer ring auxiliary shaft 80, and the lower die 11 and the second upper die 13 are closed and clamped. In this way, the control device 50 sets the support pressure P3, which is the reference pressure in the extension direction, for the outer ring cylinder 64 before the outer ring auxiliary cylinder 65 starts pressing the outer ring 16.

[0065] Then, the control device 50 judges whether the outer wheel 16 is pressed by the outer wheel auxiliary cylinder 65 (S23). Whether the outer wheel 16 is pressed may be judged, for example, by information detected by a pressure sensor (not shown), or may be judged according to the positions of the outer wheel auxiliary cylinder 65 and the outer wheel 16, etc., which have been acquired in advance. The control device 50 may also judge whether the outer wheel 16 is pressed by the outer wheel auxiliary shaft 80. When the control device 50 judges that the outer wheel 16 is pressed by the outer wheel auxiliary cylinder 65 (or the outer wheel auxiliary shaft 80), it sets a low pressure P10, which is a pressure in the extension direction and is lower than the support pressure P3, for the outer wheel cylinder 64. In this way, the control device 50 controls the pressure related to the extension and contraction of the outer wheel cylinder 64 according to the pressing state of the outer wheel 16 by at least one of the outer wheel auxiliary cylinder 65 and the outer wheel auxiliary shaft 80.

[0066] As shown in Fig. 8(B), first the outer ring auxiliary cylinder 65 comes into contact with the outer ring 16, and then, as shown in Fig. 9(A), the outer ring auxiliary shaft 80 comes into contact with the lower die 11. This pressurizes the outer ring 16 downward. As described above, since the outer ring auxiliary cylinder 65 is depressurized, the outer ring auxiliary cylinder 65 in contact with the outer ring 16 is pushed by the outer ring 16 and contracts (retreats) as shown in Figs. 8(B) and 9(A). This contraction of the outer ring auxiliary cylinder 65 due to depressurization is intended to suppress the application of a load to the outer ring cylinder 64.

[0067] 9(B), the control device 50 continues to rotate the second mold opening / closing motor 63 in the first direction until the lower end of the second upper mold 13 reaches the reference position (S24: No). At this time, the control device 50 rotates the second mold opening / closing motor 63 based on the vertical position of the second upper mold 13. The vertical position of the second upper mold 13 can be detected by, for example, a sensor (not shown), a rotary encoder of the second mold opening / closing motor 63, or a combination of these.

[0068] Next, in response to the lower end of the second upper die 13 reaching the reference position (S24: Yes), the control device 50 rotates the second die opening / closing motor 63 in the first direction with a torque that maintains the pressing force of the second upper die 13 against the lower die 11 at the set pressure and makes the descending speed of the second upper die 13 equal to or lower than the set speed (S25). Then, the control device 50 continues the process of step S24 until a set time has elapsed since the lower end of the second upper die 13 reached the reference position (i.e., since the process of step S24 was started) (S26: No). The processes of steps S24 to S26 are an example of a dehydration process.

[0069] At this time, the control device 50 increases or decreases the rotation torque of the second mold opening and closing motor 63 so that the pressing force and the lowering speed of the second upper mold 13 approach the set values. The pressing force of the second upper mold 13 can be detected by, for example, a pressure sensor (not shown). The lowering speed of the second upper mold 13 can be detected by, for example, a rotary encoder of the second mold opening and closing motor 63.

[0070] Then, the control device 50 extends the drain cylinder 42b to move the connection part 41b to the second connection position (i.e., connects the connection part 41b to the drain passage 14a of the support block 14). The control device 50 also drives the drain pump 43b to discharge the liquid dewatered from the slurry 2 through the drain passages 11a, 14a and the connection part 41b.

[0071] Furthermore, in the course of the dewatering process (S24 to S26), the outer ring 17 presses the outer ring 16 downward at a set pressure higher than the low pressure P10 of the outer ring cylinder 64.

[0072] Next, as shown in FIG. 10(A), the control device 50 determines that the pressurized spin-drying is completed in response to the elapse of the set time (S26: Yes), and sets the outer ring cylinder 64 to a lowering pressure P11 (high pressure) that is a pressure in the contracting direction and is higher than the support pressure P3. In addition, when the control device 50 determines that the pressurized spin-drying is completed, it sets a pressure in the expanding direction for the outer ring auxiliary cylinder 65, and extends the outer ring auxiliary cylinder 65 to lower the outer ring 16 to the lowering limit (S27). The process of step S27 is an example of a lowering process. The lowering process (S27) is performed between the spin-drying process (S24 to S26) and the mold opening process (S28).

[0073] Furthermore, in response to the elapse of the set time (S26: Yes), the control device 50 rotates the second die opening / closing motor 63 in the second direction, as shown in Figs. 10(B) and 11(A)(B), thereby lifting the second movable die plate 23 together with the second upper die 13, the outer wheel 17, and the outer wheel auxiliary cylinder 65 (S28). This opens the lower die 11 and the second upper die 13. The control device 50 also contracts the outer wheel auxiliary cylinder 65. The processing of step S28 is an example of a mold opening process.

[0074] Next, the control device 50 causes a robot arm (not shown) to remove the papermaking substrate 3 and the insert 15 from the lower mold 11 (S29), as shown in Fig. 12(A). The control device 50 also causes a robot arm (not shown) to insert a new insert 15 into the lower mold 11 (S30). After steps S29 and S30, the outer ring cylinder 64 is extended to raise the outer ring 16 to its upper limit (S31), as shown in Fig. 12(B). The process of step S31 is an example of a raising process.

[0075] 7(A) (however, the lower die 11 is not filled with the slurry 2). Furthermore, before step S31 is completed (the turntable 21 is rotated in step S16 in FIG. 5), the control device 50 contracts the drainage cylinder 42b to move the connection part 41b to the second retracted position.

[0076] The configuration according to this embodiment has the advantageous effects.

[0077] The control method according to the present embodiment is a control method for a papermaking machine 1 that is a dehydration device for filling a mold with a slurry 2 and dehydrating the slurry by pressure, the machine comprising a lower mold 11, an outer ring 16 arranged to surround the lower mold 11, an outer ring cylinder 64 configured to be extendable and capable of raising and lowering the outer ring 16, a second upper mold 13 that is opened and closed and clamped to the lower mold 11 by raising and lowering above the lower mold 11, an outer ring auxiliary cylinder 65 configured to be extendable and capable of pressing the outer ring 16 downward by extending, and an outer ring auxiliary shaft 80 that presses the outer ring 16 downward by contacting the lower mold 11. The control method controls the pressure related to the expansion and contraction of the outer ring cylinder 64 in accordance with at least one of the opening / closing and clamping of the second upper mold 13 to the lower mold 11, the pressing state of the outer ring 16 by the outer ring auxiliary cylinder 65, and the pressing state of the outer ring 16 by the outer ring auxiliary shaft 80.

[0078] According to this configuration, the pressure related to the control of the outer ring cylinder 64 is controlled according to the pressing state of the outer ring 16 by at least one of the outer ring auxiliary cylinder 65 and the outer ring auxiliary shaft 80. By pressing the outer ring 16 downward by at least one of the outer ring auxiliary cylinder 65 and the outer ring auxiliary shaft 80 during the mold clamping operation, the outer ring 16 can be made to move easily when the slurry 2 spreads laterally due to the pressure of the mold. On the other hand, there is a risk that high pressure will be applied to the outer ring cylinder 64 due to the outer ring 16 being pressed. In this regard, by controlling the pressure related to the control of the outer ring cylinder 64 according to the pressing state of the outer ring 16 by at least one of the outer ring auxiliary cylinder 65 and the outer ring auxiliary shaft 80, the pressure of the outer ring cylinder 64 can be controlled so that the load on the outer ring cylinder 64 does not become too large, taking into account the pressing state. As described above, according to the papermaking machine 1 according to this embodiment, it is possible to appropriately perform pressurized dewatering while reducing the load on the outer ring cylinder 64.

[0079] Before the outer wheel auxiliary shaft 80 starts pressing the outer wheel 16, a support pressure P3 that is a reference pressure in the extension direction may be set for the outer wheel cylinder 64, and after the outer wheel auxiliary shaft 80 starts pressing the outer wheel 16, a low pressure P10 that is a pressure in the extension direction and is lower than the support pressure P3 may be set for the outer wheel cylinder 64. In this way, by setting the low pressure P10 lower than the support pressure P3 for the outer wheel cylinder 64 after the outer wheel auxiliary shaft 80 starts pressing the outer wheel 16, it is possible to appropriately suppress the load on the outer wheel cylinder 64 from becoming large.

[0080] After a predetermined time has elapsed since the start of the pressurized spin-drying, it may be determined that the pressurized spin-drying is completed, and a lowering pressure P11 (high pressure) that is a pressure in the contracting direction and is higher than the support pressure P3 may be set for the outer ring cylinder 64. This allows the extraction operation to be performed smoothly after the pressurized spin-drying is completed.

[0081] When the outer ring auxiliary cylinder 65 presses the outer ring 16, pressure may be released from the outer ring auxiliary cylinder 65. This makes it possible to prevent the load on the outer ring cylinder 64 from becoming large when the outer ring auxiliary cylinder 65 presses the outer ring 16.

[0082] When it is determined that the pressurized spin-drying is completed, a pressure in the direction of extension may be set for the outer wheel auxiliary cylinder 65. This makes it possible to more smoothly perform the pulling operation after the pressurized spin-drying is completed.

[0083] The method for producing the papermaking substrate 3 according to this embodiment may include a step of pressurizing and dehydrating the slurry 2 using the above-mentioned control method to obtain the papermaking substrate 3. According to this production method, a papermaking substrate 3 that has been appropriately pressurized and dehydrated can be produced.

[0084] The method for producing a gear according to this embodiment may include a step of obtaining a papermaking substrate 3 by the above-mentioned method for producing the papermaking substrate 3, and a step of obtaining a gear by forming teeth on the outer peripheral surface of the papermaking substrate 3. According to this production method, a gear can be appropriately produced from the papermaking substrate 3 that has been appropriately pressurized and dehydrated. [Explanation of symbols]

[0085] 1...papermaking machine (dewatering device), 2...slurry (liquid raw material), 3...papermaking base material (paper body), 11...lower mold, 13...second upper mold (upper mold), 16...outer ring, 50...control device, 64...outer ring cylinder, 65...outer ring auxiliary cylinder. 80...outer ring auxiliary shaft.

Claims

1. A control method for a dehydration apparatus which fills a mold with a liquid raw material and dehydrates it by pressure, the control method comprising: a lower mold; an outer ring arranged to surround the lower mold; an outer ring cylinder configured to be extendable and contractable and which raises and lowers the outer ring; an upper mold which opens and closes relative to the lower mold by raising and lowering above the lower mold; an outer ring auxiliary cylinder configured to be extendable and which presses the outer ring downward by extending; and an outer ring auxiliary shaft which presses the outer ring downward by contacting the lower mold, opening and closing and clamping the upper mold relative to the lower mold; and controlling pressure related to the expansion and contraction of the outer wheel cylinder in accordance with at least one of a pressing state of the outer wheel by the outer wheel auxiliary cylinder and a pressing state of the outer wheel by the outer wheel auxiliary shaft.

2. Before the outer ring auxiliary shaft starts to press the outer ring, a reference pressure in an extension direction is set for the outer ring cylinder; 2. The control method according to claim 1, further comprising the step of: setting, after the outer wheel auxiliary shaft starts to press the outer wheel, a low pressure in the direction of extension of the outer wheel cylinder, which is lower than the reference pressure.

3. 3. The control method according to claim 2, further comprising determining that the pressurized spin-drying is completed after a predetermined time has elapsed since the start of the pressurized spin-drying, and setting a high pressure in a contracting direction for the outer ring cylinder that is higher than the reference pressure.

4. 3. The control method according to claim 2, further comprising the step of: releasing pressure from said outer-wheel auxiliary cylinder when said outer-wheel auxiliary cylinder is pressing said outer wheel.

5. 4. The control method according to claim 3, further comprising the step of: setting a pressure in a direction for extending said outer wheel auxiliary cylinder when it is determined that the pressurized dewatering is completed.

6. A method for producing a paper product, comprising the step of pressurizing and dehydrating the liquid raw material by the control method according to any one of claims 1 to 5 to obtain a paper product.

7. A step of obtaining a paper article by the method for producing a paper article according to claim 6; and forming teeth on the outer peripheral surface of the paper body to obtain a gear.

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