Conveyance device, press device system, and method for controlling conveyance device

Abstract

A conveyance device (1A) comprises: a feeder that intermittently feeds a belt-shaped body to a press device (2) by a set length each time press processing is completed; a pushing device that pushes tensioners (21)-(23) against the belt-shaped body to generate tension in the belt-shaped body and reduce the speed of the belt-shaped body fed by the feeder; a measurement unit that measures the length of the belt-shaped body actually fed by the feeder from the previous specific press state to the current specific press state each time the press device (2) enters a specific press state in press processing; and a control unit that obtains a deviation of the actual feed length of the belt-shaped body measured by the measurement unit from the set length, and controls the force by which the pushing device pushes the tensioners against the belt-shaped body on the basis of the deviation.

Description

Conveyance device, press system, and method for controlling the conveyance device

[0001] The present disclosure relates to a conveying device, a press system, and a method for controlling a conveying device.

[0002] Some conveying devices are installed in press machines and intermittently feed a set length of strip material to the press machine each time press processing is completed. Among such conveying devices, devices that can feed strip material to the press machine with high precision have been developed.

[0003] For example, Patent Document 1 discloses a conveying device that includes a storage device in which an error in the feed length of a strip to be fed to a press device is stored in advance as correction information, and a controller that controls a motor, which is a drive source for feeding the strip, based on the correction information.

[0004] Japanese Patent Application Laid-Open No. 2006-122966

[0005] The conveying device described in Patent Document 1 requires that correction information for the strip be calculated in advance and stored in a storage device. As a result, this conveying device has difficulty feeding the strip with high accuracy when the correction information for the strip is not stored in the storage device in advance. For example, the conveying device described in Patent Document 1 has difficulty feeding the strip with high accuracy when the thickness or surface friction of the strip changes.

[0006] The present disclosure has been made to solve the above-mentioned problems, and aims to provide a conveying device, a press machine system, and a control method for a conveying device that can feed a strip with high accuracy even without correction information for the strip.

[0007] To achieve the above object, the conveying device according to the present disclosure includes a feeding device, a pressing device, a measuring unit, and a control unit. The feeding device intermittently feeds a strip to a press device by a set length each time a press process is completed. The pressing device applies tension to the strip by pressing a tensioner against the strip, thereby generating tension in the strip and slowing down the speed of the strip fed by the feeding device. Each time the press device reaches a specific press state during press processing, the measuring unit measures the length of the strip actually fed by the feeding device between the previous specific press state and the current specific press state. The control unit calculates a deviation between the actual feed length of the strip measured by the measuring unit and the set length, and controls the force with which the pressing device presses the tensioner against the strip based on the deviation.

[0008] According to the configuration of the present disclosure, the control unit determines the deviation between the actual feed length of the strip measured by the measurement unit and the set length, and controls the force with which the pressing device presses the tensioner against the strip based on the deviation. This allows the conveying device to feed the strip with high accuracy even without strip correction information.

[0009] a right side view of a conveying device according to the first embodiment of the present disclosure; a front view of a tensioner provided in the conveying device according to the first embodiment of the present disclosure; a cross-sectional view of a press device provided with the conveying device according to the first embodiment of the present disclosure; a cross-sectional view taken along the IV-IV section line shown in FIG. 3; an enlarged side view of a hitch feeder provided in the conveying device according to the first embodiment of the present disclosure; an enlarged side view of a modified example of a hitch feeder provided in the conveying device according to the first embodiment of the present disclosure; a hardware configuration diagram of a controller provided in the conveying device according to the first embodiment of the present disclosure; a block diagram of a controller provided in the conveying device according to the first embodiment of the present disclosure; a flowchart of a first tensioner control process performed by a controller provided in the conveying device according to the first embodiment of the present disclosure; Graph showing an example of the progression of the pressing force of the tensioner and auxiliary tensioner provided in the conveying device according to embodiment 4 of the present disclosure. A conceptual diagram of PID control used by the tensioner control unit of the controller provided in the conveying device according to embodiment 1 of the present disclosure to adjust the electro-pneumatic regulator. A block diagram of the controller provided in the conveying device according to embodiment 2 of the present disclosure. A right side view of the conveying device according to embodiment 3 of the present disclosure. An enlarged side view of the tension measuring device provided in the conveying device according to embodiment 3 of the present disclosure. A front view of a movable roll provided in the tension measuring device provided in the conveying device according to embodiment 3 of the present disclosure. A right side view of the conveying device according to embodiment 4 of the present disclosure. Graphs showing an example of the progression of the slide position of the press device, the total feed length of the metal strip by the conveying device according to embodiment 4 of the present disclosure, the feed speed of the metal strip by the conveying device according to embodiment 4 of the present disclosure, and the pressing force of the tensioner and auxiliary tensioner on the metal strip provided in the conveying device according to embodiment 4 of the present disclosure. Block diagram of a controller included in a conveying device according to a fifth embodiment of the present disclosure. Diagram showing an example of the configuration of a database stored in a database storage unit of a controller included in a conveying device according to a fifth embodiment of the present disclosure. Flowchart of a switching process performed by a controller included in a conveying device according to a fifth embodiment of the present disclosure. Flowchart of a second tensioner control process performed by a controller included in a conveying device according to a fifth embodiment of the present disclosure.

[0010] A conveying device, a press machine system, and a method for controlling a conveying device according to embodiments of the present disclosure will be described in detail below with reference to the drawings. Note that identical or equivalent parts in the drawings are designated by the same reference numerals. In addition, in the Cartesian coordinate system XYZ shown in the drawings, the length direction of the metal strip conveyed by the conveying device is the X axis, and the width direction of the strip is the Y axis, and the direction perpendicular to the X axis and the Y axis is the Z axis. This coordinate system will be referenced as appropriate below in the description.

[0011] (Embodiment 1) In a conveying device according to embodiment 1, a feeder supplies and discharges a metal strip to a press device, and a tensioner contacts the metal strip to adjust the feed speed of the metal strip. In this conveying device, a controller controls the pressing force of the tensioner to control the feed length of the metal strip to the press device.

[0012] First, the overall configuration of the conveying device will be described with reference to Figures 1 to 6. In the following description, the configuration of the conveying device will be described using an example in which the feeding device is a hitch feeder. The configuration of the press device will also be described.

[0013] FIG. 1 is a right side view of a conveying device 1A according to the first embodiment. FIG. 2 is a front view of tensioners 21-23 provided in the conveying device 1A. FIG. 3 is a cross-sectional view of a press device 2 equipped with the conveying device 1A. FIG. 4 is a cross-sectional view taken along the IV-IV section line shown in FIG. 3. FIG. 5 is an enlarged side view of a hitch feeder 30 provided in the conveying device 1A. FIG. 6 is an enlarged side view of a modified version of the hitch feeder 30. Note that FIG. 3 shows a cross-section of the press device 2 taken along a plane parallel to the YZ plane shown in FIG. 1. Furthermore, in FIGS. 3 and 4, solid lines indicate the components of the press device 2 when the crankshaft 26 has rotated to bottom dead center, and dashed double-dashed lines indicate the components of the press device 2 when the crankshaft 26 has rotated to top dead center. Furthermore, hatching is omitted in FIGS. 3 and 4. For ease of understanding, the shapes of the components of the conveying device 1A are simplified in FIGS. 1, 2, 5, and 6.

[0014] 1, the conveying device 1A is installed in the press device 2 and feeds a metal strip 3 to be processed in the longitudinal direction into the press device 2. To feed the metal strip 3 into the press device 2, the conveying device 1A includes an uncoiler 10 that pulls out one end of the metal strip 3 from the coil 4, tensioners 21-23 that tension the metal strip 3 pulled out from the uncoiler 10, and a hitch feeder 30 that pulls out the metal strip 3 that has been passed between dies 25 of the press device 2 and feeds it from the press device 2.

[0015] The coil 4 is formed by winding up the metal strip 3. The uncoiler 10 unwinds the coil 4, thereby pulling out one end of the metal strip 3 from the coil 4. After being pulled out from the coil 4, the metal strip 3 passes through a leveler 13 provided downstream of the uncoiler 10, i.e., on the right side, and equipped with a pair of pinch rolls 11, 12. This reduces distortion of the metal strip 3.

[0016] After passing through the leveler 13, the metal strip 3 is pulled out onto the stage 24 downstream of the press device 2, i.e., on the left side of the press device 2. The stage 24 has a flat and horizontal stage surface, which supports the metal strip 3 and prevents it from bending. Tensioners 21-23 are provided on the stage 24, and the metal strip 3 is sandwiched between the tensioners 21-23 and the stage 24. The stage 24 is also called the conveyance base because it is the foundation of the conveyance device 1A.

[0017] The tensioners 21-23 contact the upper surface of the metal strip 3 to apply tension to the metal strip 3. Specifically, as shown in FIGS. 1 and 2, each of the tensioners 21-23 is formed in a rectangular parallelepiped shape. To prevent damage to the metal strip 3, the tensioners are made of a material that is softer than the material of the metal strip 3, such as felt or rubber. The tensioners 21-23 are arranged with the bottom surfaces of the rectangular parallelepipeds facing downward. Furthermore, as shown in FIG. 2, the tensioners 21-23 are connected to piston rods 212, 222, and 232 attached to air cylinders 211, 221, and 231 that extend from above. The tensioners 21-23 are pressed by the piston rods 212, 222, and 232 to press the metal strip 3 against the stage 24, thereby tensioning the metal strip 3. In this way, the tensioners 21-23 remove the deflection of the metal strip 3.

[0018] In addition, in the tensioners 21-23, the piston rods 212, 222, 232 are moved up and down by the air cylinders 211, 221, 231, respectively, to adjust the force applied to the metal strip 3, i.e., the pressing force. In this way, the tensioners 21-23 adjust the tension generated in the metal strip 3. Note that by adjusting this tension, the inertial force when the metal strip 3 is fed by the hitch feeder 30 is adjusted. The details of tension adjustment will be described later.

[0019] Furthermore, the tensioners 21-23 are oriented such that the longitudinal direction of the rectangular shape in front view faces the left-right direction, i.e., the Y direction. In this orientation, the tensioners 21-23 are arranged in the Y direction. As a result, when the metal strip 3 is fed, the tensioners 21-23 press the entire metal strip 3 in the Y direction, applying friction to the entire metal strip 3 in the Y direction. The metal strip 3 is passed through the press device 2 with any slack removed by the tensioners 21-23.

[0020] As shown in FIGS. 1, 3, and 4, the press device 2 has a die 25. As shown in FIGS. 3 and 4, the press device 2 also has a crankshaft 26 that converts the rotational motion of the prime mover into reciprocating motion, and a slide 28 that moves up and down in conjunction with the rotational motion of the crankshaft 26 via a connecting rod 27 connected to the crankshaft 26. In the press device 2, the upper die of the die 25 moves relative to the lower die due to the up and down movement of the slide 28. As shown in FIG. 1, a metal strip 3 passes between the upper and lower dies of the die 25, and the press device 2 presses the metal strip 3 by the up and down movement of the slide 28. For example, the press device 2 forms each portion of the fins included in a heat exchanger. For example, the press device 2 forms a through hole 301, shown in FIG. 5, that includes a burring portion. In the press device 2, the hitch feeder 30 sequentially feeds the metal strip 3 a fixed distance for each press process in order to form the through holes 301 one after another.

[0021] To perform this sequential feeding, the hitch feeder 30 has, as shown in Figure 5, a pin 31 to be inserted into a through hole 301 formed in the metal strip 3 by the press device 2, and a movable block 32 that moves the pin 31 while the pin 31 is inserted into the through hole 301 to feed the metal strip 3.

[0022] The pin 31 has a cylindrical shape with an inclined tip end surface and an outer diameter smaller than the diameter of the through hole 301 to facilitate insertion into the through hole 301. The pin 31 is loosely inserted into a cylindrical portion 311 that extends in the vertical direction. As a result, the pin 31 is held in the cylindrical portion 311 with its axis facing in the vertical direction.

[0023] The cylindrical portion 311 has a closed lower end and a compression coil spring 312 housed in the internal space of the cylindrical portion 311. The lower end of the pin 31 is loosely inserted into the cylindrical portion 311 and is supported by the compression coil spring 312. As a result, the tip, i.e., the upper end, of the pin 31 can be moved up and down by expanding and contracting the compression coil spring 312.

[0024] Meanwhile, the lower end of the cylindrical portion 311 is fixed to the upper surface of the movable block 32. Although not shown, the movable block 32 is disposed at a position where the left-right position of the axis of the pin 31, i.e., the Y position of the axis of the pin 31, coincides with the Y position of the center of the through-hole 301 formed in the metal strip 3. The movable block 32 can be reciprocated in the up-down and back-and-forth directions, i.e., the Z direction and the X direction, from that Y position by a drive device not shown.

[0025] Specifically, the movable block 32 moves a certain distance in the +Z direction, as indicated by arrow A1 in FIG. 5 , from a position where the upper end of the pin 31 is separated from the underside of the metal strip 3. As a result, the movable block 32 presses the upper end of the pin 31 against the underside of the metal strip 3, and the pin 31 compresses the compression coil spring 312, causing the elastic force of the compression coil spring 312 to bias the pin 31. Then, as indicated by arrow A2, the movable block 32 moves in the +X direction by a stroke distance greater than the pitch of the through holes 301 in the metal strip 3. During this movement, when the pin 31 passes under the through hole 301, the compression coil spring 312 biases the pin 31 in the +Z direction, causing the pin 31 to enter the through hole 301. With the pin 31 inserted into the through hole 301, the movable block 32 moves further in the +X direction, feeding the metal strip 3 in the +X direction. Thereafter, the movable block 32 moves in the -Z direction by the above-mentioned fixed distance, as indicated by arrow A3, to remove the pin 31 from the through-hole 301. Furthermore, the movable block 32 moves in the -X direction by the above-mentioned stroke, as indicated by arrow A4, to return to its original position. The movable block 32 repeats this operation every time the press device 2 performs press working. As a result, the conveying device 1A intermittently feeds the metal strip 3 in the +X direction.

[0026] The movable block 32 may be reciprocated in the X direction by a drive device (not shown), as shown in Fig. 6. Even with this configuration, the movable block 32 can insert the pins 31 into the through holes 301 to intermittently feed the metal strip 3 in the +X direction.

[0027] In the hitch feeder 30 shown in FIG. 5 , as described above, to facilitate insertion of the pin 31 into the through-hole 301, not only is the upper end surface of the pin 31 inclined, but the outer diameter of the pin 31 is smaller than the inner diameter of the through-hole 301. As a result, when the pin 31 enters the through-hole 301, a gap exists between the outer periphery of the pin 31 and the inner wall of the through-hole 301. As a result, when the movable block 32 moves in the +X direction indicated by arrow A2 and then stops, the metal strip 3 moves in the +X direction beyond the movable block 32 due to inertia by a maximum amount equal to the gap between the outer periphery of the pin 31 and the inner wall of the through-hole 301. The magnitude of this inertia varies depending on various conditions, such as variations in the thickness of the metal strip 3 and friction of the tensioners 21-23. As a result, the feeding distance of the metal strip 3, i.e., the feeding length, differs for each intermittent feed. 6, when the movable block 32 stops reciprocating, the metal strip 3 may climb over the pin 31 due to inertial force, resulting in a feed length that is longer than the intended feed length. In this context, it is difficult for the conveying device 1A to feed the metal strip 3 by a fixed feed length with high precision.

[0028] Therefore, in order to feed the metal strip 3 by a fixed feed length with high precision, the conveying device 1A is provided with a controller 40A that controls the pressing force of the tensioners 21-23 against the metal strip 3. Next, the configuration of the controller 40A will be described with reference to FIGS.

[0029] Fig. 7 is a hardware configuration diagram of the controller 40A provided in the transport device 1A. Fig. 8 is a block diagram of the controller 40A. For ease of understanding, Figs. 7 and 8 also show the configuration of the devices connected to the controller 40A.

[0030] As shown in FIG. 7 , the controller 40A includes a computer including a CPU (Central Processing Unit) 41 and a memory 42 configured with a ROM (Read-Only Memory), a RAM (Random Access Memory), and the like. The memory 42 includes a feed length data storage unit 43, a set length data storage unit 44, and an angle data storage unit 45 (described later) shown in FIG. 8 . Returning to FIG. 7 , the controller 40A performs various processes for controlling the components of the conveying device 1A by having the CPU 41 read various programs stored in the ROM of the memory 42 into the RAM and execute them. For example, the controller 40A executes a hitch feeder drive program to control the drive device (not shown) of the hitch feeder 30. The controller 40A also executes a tensioner control program to control the pressing forces of the tensioners 21-23.

[0031] 7, the controller 40A has an I / O port (Input / Output Port) 46. The I / O port 46 is electrically connected to a control unit 5 provided in the press device 2 in order to obtain drive information for the press device 2. The I / O port 46 is also electrically connected to a length measurement sensor 50 that measures the feed length of the metal strip 3 and electropneumatic regulators 213, 223, and 233 that adjust the air pressure of the air cylinders 211, 221, and 231 in order to control the pressing forces of the tensioners 21-23.

[0032] The control unit 5 controls each component of the press apparatus 2. The control unit 5 transmits to the CPU 41 data on the rotation angle of the crankshaft 26 relative to a reference position when the crankshaft 26 rotates. For example, the control unit 5 transmits to the CPU 41 data on the rotation angle of the crankshaft 26 when the rotation angle at top dead center is defined as 0°. More specifically, the control unit 5 transmits to the CPU 41 data on the rotation angle of the crankshaft 26 when the angle at which the crankpin 262 is directly upward D relative to the axis A of the main shaft 261 shown in FIG. 4 is defined as 0°, and rotation in the clockwise direction C shown in FIG. 4 is defined as forward rotation. Returning to FIG. 7 , the control unit 5 periodically transmits such data via the I / O port 46. This allows the control unit 5 to transmit press status information and transfer timing information to the CPU 41.

[0033] Here, the pressed state refers to a state in which the press members provided in the press device 2, such as the crankshaft 26 and slide 28, are in a specific position and orientation. To give a more specific example, the pressed state refers to a state in which the crankshaft 26 provided in the press device 2 is at a specific rotation angle.

[0034] Meanwhile, the length measuring sensor 50 is provided to measure the feed length of the metal strip 3. More specifically, the length measuring sensor 50 is fixed to a gate-shaped holder (not shown). As shown in FIG. 1 , the length measuring sensor 50 is disposed on a portion of the metal strip 3 above the stage 24, between the tensioners 21-23 and the press device 2. Although not shown, the length measuring sensor 50 includes a light source that irradiates the object to be measured with light, a line sensor that receives light reflected by the object to periodically generate image data, and a calculation unit that performs a matching process on the image data periodically generated by the line sensor to determine the displacement and speed of the object to be measured. By being disposed in the above-described position, the length measuring sensor 50 periodically measures the displacement and speed of a portion of the metal strip 3 located below the length measuring sensor 50. After measuring the displacement and speed of the portion of the metal strip 3, the length measuring sensor 50 transmits the displacement and speed data to the CPU 41 via the I / O port 46.

[0035] 7, the electropneumatic regulators 213, 223, and 233 adjust the air pressure of the air cylinders 211, 221, and 231 shown in FIG. 1 in response to commands from the CPU 41. As a result, the electropneumatic regulators 213, 223, and 233 press the tensioners 21-23 against the metal strip 3 with a pressing force according to the commands from the CPU 41, and adjust the frictional force when the metal strip 3 is fed.

[0036] The controller 40A is electrically connected to these devices and equipment, and uses data obtained from these devices and equipment to perform the first tensioner control process that controls the pressing forces of the tensioners 21-23. In order to perform this first tensioner control process, the controller 40A is equipped with various blocks configured as software shown in FIG. 8. In more detail, the controller 40A is equipped with a feed length measuring unit 47 and a tensioner control unit 48.

[0037] The feed length measurement unit 47 receives data on the rotation angle of the crankshaft 26 periodically transmitted from the control unit 5 of the press machine 2. The feed length measurement unit 47 also receives data on the displacement and speed of the metal strip 3 periodically transmitted from the length measurement sensor 50. Then, based on the received data on the rotation angle of the crankshaft 26 and the displacement and speed data of the metal strip 3, the feed length measurement unit 47 calculates the actual distance the metal strip 3 has been fed between the previous specific angle and the current specific angle each time the crankshaft 26 rotates to a specific angle, i.e., the feed length. In this way, the feed length measurement unit 47 obtains the feed length per press operation cycle each time the press machine 2 performs press working. The feed length measurement unit 47 then transmits the obtained feed length data to the tensioner control unit 48.

[0038] The tensioner control unit 48 receives the feed length data transmitted from the feed length measurement unit 47. Meanwhile, the set length data storage unit 44 stores data on the ideal feed length that the metal strip 3 should be fed per press operation cycle, i.e., set length data. The tensioner control unit 48 reads the set length data from the set length data storage unit 44 and calculates the deviation of the actual feed length from the set length based on the feed length data received from the feed length measurement unit 47 and the read set length. Furthermore, based on the calculated deviation, the tensioner control unit 48 determines the air pressure of the air cylinders 211, 221, and 231 that realizes the pressing force of the tensioners 21-23 to reduce the deviation. The tensioner control unit 48 calculates this air pressure each time data on the feed length per cycle is transmitted from the feed length measurement unit 47.

[0039] The tensioner control unit 48 sends a signal corresponding to the determined air pressure to the electropneumatic regulators 213, 223, and 233, causing the electropneumatic regulators 213, 223, and 233 to adjust the air pressure in the air cylinders 211, 221, and 231. As a result, the tensioner control unit 48 adjusts the air pressure in the air cylinders 211, 221, and 231 shown in FIGS. 1 and 2 to the determined air pressure. As a result, the tensioner control unit 48 presses the tensioners 21-23 against the metal strip 3 with a pressing force that reduces the deviation. This allows the metal strip 3 to be fed by a constant feed length with high precision.

[0040] 9 and 10, a method for controlling the tensioners 21-23 by the controller 40A will be described in more detail. In the following description, it is assumed that the press apparatus 2 has a start button (not shown), and that pressing the start button starts the transport apparatus 1A attached to the press apparatus 2.

[0041] FIG. 9 is a flowchart of a first tensioner control process performed by the controller 40A included in the conveying device 1A.

[0042] First, a start button (not shown) provided on the press device 2 is pressed, which starts the press device 2. Furthermore, the control unit 5 of the press device 2 outputs a signal to start the transport device 1A.

[0043] When the conveying device 1A is started, the controller 40A provided in the conveying device 1A first executes a tensioner control program (not shown) by the CPU 41 shown in FIG. 7, and as a result, the flow of the first tensioner control process shown in FIG. 9 is started.

[0044] In addition, in the conveying device 1A, the movable block 32 of the hitch feeder 30 begins to operate due to a drive device (not shown). Furthermore, the length measurement sensor 50 is activated. Meanwhile, when the press device 2 is activated, the crankshaft 26 described above begins to rotate in the press device 2 for press processing. Figure 10 shows the relationship between the rotation angle of the crankshaft 26 of the press device 2, the feed length and speed of the metal strip 3, etc. after the conveying device 1A and the press device 2 are activated.

[0045] Figure 10 is a graph showing an example of the changes in the position of the slide 28 of the press device 2, the total feed length of the metal strip 3 by the conveying device 1A, the feed speed of the metal strip 3 by the conveying device 1A, and the pressing force of the tensioners 21-23.

[0046] 10 refers to the length of the metal strip 3 that the hitch feeder 30 has fed to the press machine after the length measuring sensor 50 has been activated. For example, the total feed length refers to the cumulative length measured after the length measuring sensor 50 has been activated.

[0047] Moreover, over time, the rotation angle of the crankshaft 26 of the press apparatus 2 repeatedly fluctuates between 0°, 90°, 180°, 270°, and then returns to 0°, before returning to 90°, 180°, etc. In Figure 10, the horizontal axis of the graph originally represents time, but for ease of understanding, the horizontal axis of the graph shows the rotation angle of the crankshaft 26 of the press apparatus 2.

[0048] 10 , in the press apparatus 2, the slide 28 reciprocates in response to the rotation of the crankshaft 26. In detail, the slide 28 of the press apparatus 2 reciprocates, reaching top dead center P1 when the crankshaft 26 has a rotation angle of 0° and reaching bottom dead center P2 when the crankshaft 26 has a rotation angle of 180°.

[0049] On the other hand, in the conveying device 1A, as shown in the graph of "Total feed length of metal strip" in Fig. 10 and the graph of "Feed speed of metal strip" in Fig. 10, the feed speed of the metal strip 3 reaches a maximum value at a rotation angle of 0°, where the crankshaft 26 is at top dead center P1, and becomes 0 at a rotation angle of 90°-270° of the crankshaft 26. As a result, the total feed length of the metal strip 3 increases at a rotation angle of 270°-90° of the crankshaft 26, and remains constant at a rotation angle of 90°-270°.

[0050] In the press machine 2, the control unit 5 periodically transmits data on the rotation angle of the crankshaft 26 to the feed length measurement unit 47 of the controller 40A. In the conveying device 1A, the length measurement sensor 50 periodically measures the displacement and speed of the metal strip 3. The displacement here refers to the total feed length described above. Hereinafter, this will be referred to as the total feed length. The length measurement sensor 50 transmits data on the measured total feed length and speed to the feed length measurement unit 47 of the controller 40A each time a measurement is performed.

[0051] Returning to FIG. 9 , when the flow of the first tensioner control process is started, first, the feed length measuring unit 47 of the controller 40A receives rotation angle data of the crankshaft 26 from the control unit 5 of the press machine 2 (step S1).

[0052] Next, the feed length measuring unit 47 determines whether the received rotation angle data of the crankshaft 26 is a specific angle (step S2).

[0053] Here, the specific angle refers to the rotation angle θa of the crankshaft 26 shown in Figure 10, which is the rotation angle θa of the crankshaft 26 immediately before the slide 28 of the press device 2 moves from the bottom dead center P2 toward the top dead center P1 and the hitch feeder 30 starts feeding the metal strip 3.

[0054] To explain step S2 in more detail, the specific angle data is stored in the angle data storage unit 45 shown in Fig. 8. The feed length measurement unit 47 reads the specific angle data from the angle data storage unit 45 and uses the data to determine whether the received rotation angle data of the crankshaft 26 is the specific angle.

[0055] If the feed length measuring unit 47 determines that the rotation angle data is not the specific angle (No in step S2), the process returns to step S1 and waits for the next transmission of rotation angle data of the crankshaft 26. As a result, the feed length measuring unit 47 repeats steps S1 and S2 until it receives rotation angle data of the crankshaft 26 that is the specific angle.

[0056] As described above, the length measurement sensor 50 periodically transmits data on the total feed length and speed of the metal strip 3. As a result, the feed length measurement unit 47 periodically receives the data on the total feed length and speed of the metal strip 3. If the feed length measurement unit 47 determines that the rotation angle data is a specific angle (Yes in step S2), it determines that the total feed length received immediately after the data received periodically is the current total feed length (step S3).

[0057] As will be described later, in a later step, the feed length measuring unit 47 stores the above-mentioned current total feed length in the feed length data storage unit 43. As a result, the previous total feed length before the current total feed length is stored in the feed length data storage unit 43. Following step S3, the feed length measuring unit 47 reads out the previous total feed length from the feed length data storage unit 43 (step S4).

[0058] The feed length measuring unit 47 subtracts the value of the previous total feed length read in step S4 from the value of the current total feed length obtained in step S3 to calculate the feed length from the previous specific angle (step S5).

[0059] After calculating the feed length since the previous specific angle, the feed length measuring unit 47 reads out the set length data from the feed length data storage unit 43 and calculates the deviation from the set length by subtracting the read-out set length value from the calculated value of the feed length since the previous specific angle (step S6). The feed length measuring unit 47 transmits the calculated deviation data to the tensioner control unit 48. After calculating the deviation or transmitting the deviation data, the feed length measuring unit 47 stores the current total feed length in the feed length data storage unit 43.

[0060] The tensioner control unit 48 adjusts the electropneumatic regulators 213, 223, 233 based on the deviation received from the feed length measuring unit 47 (step S7). An example of this adjustment method is shown in FIG.

[0061] FIG. 11 is a conceptual diagram of PID control (Proportional Integral Differential Controller) used by the tensioner control unit 48 to adjust the electro-pneumatic regulators 213, 223, and 233.

[0062] The tensioner control unit 48 uses the PID control shown in FIG. 11 . In this case, the set feed length is x(t), the feed length in step S5 is x'(t), and the deviation in step S6 is e(t). These data are applied to PID control to determine the pressure values ​​of the electropneumatic regulators 213, 223, and 233, which are the manipulated variable u(t). The tensioner control unit 48 then adjusts the electropneumatic regulators 213, 223, and 233 to the determined pressure values. As a result, the tensioner control unit 48 adjusts the air pressures of the air cylinders 211, 221, and 231 shown in FIGS. 1 and 2 to the determined pressures, and presses the tensioners 21-23 against the metal strip 3 with a pressing force that reduces the deviation, for example, the pressing force for the period P0 shown in the "Tensioner Pressing Force" graph in FIG. 10 . As a result, the metal strip 3 is fed by a constant feed length with high precision.

[0063] The air cylinders 211, 221, and 231 described above are examples of pressing devices as defined in the present disclosure. The feed length measuring unit 47 of the controller 40A is an example of a measuring unit as defined in the present disclosure. The tensioner control unit 48 of the controller 40A is an example of a control unit as defined in the present disclosure. The slide 28 of the press apparatus 2 is an example of a slide mechanism as defined in the present disclosure. The state in which the crankshaft 26 of the press apparatus 2 is oriented at a specific angle, i.e., the rotational angle θa shown in FIG. 10 , is an example of the press apparatus being in a specific pressing state as defined in the present disclosure.

[0064] As described above, in the conveying device 1A according to the first embodiment, the controller 40A calculates the deviation between the actual feed length of the metal strip 3 and the set length, and performs control to press the tensioners 21-23 against the metal strip 3 with a pressing force based on the deviation. Therefore, the controller 40A can feed the metal strip 3 with high accuracy even without correction information for the metal strip 3.

[0065] In addition, since the controller 40A presses the tensioners 21-23 against the metal strip 3 with a pressing force based on the deviation between the actual feed length and the set length, the conveying device 1A can feed the metal strip 3 with high precision even if various conditions such as the thickness and friction of the metal strip 3 change.

[0066] (Modification) Preferably, one length measuring sensor 50 described in the first embodiment is provided at the center of the width of the metal strip 3, i.e., the center in the Y direction. Alternatively, one length measuring sensor 50 is provided at each end in the Y direction of the metal strip 3. If multiple length measuring sensors 50 are provided in the Y direction, it is possible to obtain the displacement of the metal strip 3, i.e., the average value of the total feed length, and also to measure whether or not the metal strip 3 is meandering and the amount of meandering.

[0067] Furthermore, in the first embodiment, a device configured with air cylinders 211, 221, and 231 and electropneumatic regulators 213, 223, and 233 has been described as an example of a pressing device. However, the pressing device may have a configuration other than the above. For example, the pressing device may be configured with an elastic member, such as a compression spring, that biases the tensioners 21-23 by elastically deforming, and a prime mover, such as a servomotor, that elastically deforms the elastic member by pressing it. A pressing device configured with air cylinders 211, 221, and 231 and electropneumatic regulators 213, 223, and 233 may have a slow response, and may not be able to adequately control the pressing of the tensioners 21-23 against the metal strip 3 when the processing speed of the press device 2 is high. However, a pressing device configured with the above compression springs and servomotors has a fast response and can adequately keep up even when the processing speed of the press device 2 is high.

[0068] (Embodiment 2) In Embodiment 1, the controller 40A receives data on the rotation angle of the crankshaft 26 from the control unit 5 of the press apparatus 2 and determines when the crankshaft 26 reaches a specific angle. In other words, it determines the timing when the press apparatus 2 reaches a specific press state. The controller 40A then determines the feed length of the metal strip 3 from that timing from the previous specific press state to the current specific press state, i.e., the feed length of one cycle. However, the controller 40A is not limited to this. The controller 40A may also determine the timing when the press apparatus 2 reaches a specific press state from other data and determine the feed length of one cycle.

[0069] In the transport device 1B according to the second embodiment, the controller 40B determines the timing at which the press device 2 enters a specific pressing state from the speed data of the metal strip 3 transmitted by the length measurement sensor 50.

[0070] A conveying device 1B according to the second embodiment will be described below with reference to Fig. 12 in addition to Fig. 10. In the second embodiment, the configuration different from the first embodiment will be mainly described.

[0071] As shown in the graph of "Feed speed of metal strip" in Figure 10, the speed of the metal strip 3 reaches a peak value every time the slide 28 of the press device 2 shown in the graph of "Position of slide of press device" in Figure 10 reaches the top dead center P1, that is, every time the rotation angle of the crankshaft 26 of the press device 2 reaches 0°.

[0072] Therefore, the controller 40B provided in the transport device 1B according to the second embodiment uses threshold data for determining whether the speed of the metal strip 3 has reached its peak value. Fig. 12 shows the configuration of the controller 40B.

[0073] FIG. 12 is a block diagram of a controller 40B included in a transport device 1B according to the second embodiment.

[0074] As shown in FIG. 12 , the controller 40B includes a threshold data storage unit 49 that stores threshold data for the above-described determination. When the controller 40B receives data on the total feed length and speed of the metal strip 3 from the length measurement sensor 50, it reads the threshold data from the threshold data storage unit 49 and determines whether the received speed value exceeds the read threshold, thereby determining whether the speed has reached its peak value. The controller 40B repeats this determination to obtain the times T1, T2, ..., shown in the graph of "Metal Strip Feed Speed" in FIG. 10 , at which the speed reached its peak value. Each time a new time T1, T2, ... is obtained, the controller 40B calculates the time Ta at which the rotational angle of the crankshaft 26 described in the first embodiment reaches a specific angle, i.e., angle θa, using the following Equation 1:

[0075]

[0076] 12 stores the total feed length and speed data in the feed length data storage unit 43 every time it receives the data on the total feed length and speed of the metal strip 3 from the length measurement sensor 50. As a result, the controller 40B stores the past total feed length and speed data for a certain period of time in the feed length data storage unit 43. Every time the controller 40B obtains new times T1, T2, ... and calculates time Ta, it uses the data stored in the feed length data storage unit 43 to calculate the total feed length of the metal strip 3 at the time Ta.

[0077] Furthermore, the controller 40B calculates the feed length of the metal strip 3 per cycle from the total feed length of the metal strip 3 at the latest time Ta and the total feed length of the metal strip 3 at the previous time Ta. This allows the controller 40B to calculate the feed length referred to in step S5 of the flowchart in FIG. 9 described in the first embodiment. The controller 40B performs control to press the tensioners 21-23 against the metal strip 3 with a pressing force that reduces the deviation by performing each step from step S6 onward in the flowchart. As a result, the metal strip 3 is fed a constant feed length with high precision.

[0078] The length measuring sensor 50 provided in the above-described conveying device 1B is an example of a length measuring unit and a speed measuring unit as defined in the present disclosure. The controller 40B is an example of a calculation unit as defined in the present disclosure. The length measuring unit is also referred to as a total feed length measuring unit. The calculation unit is also referred to as a feed length calculation unit.

[0079] As described above, in the conveyance device 1B according to the second embodiment, the controller 40B determines the most recent time Ta at which the rotational angle of the crankshaft 26 reached a specific angle and the time Ta immediately before that from the speed of the metal strip 3, and calculates the feed length of the metal strip 3 after the rotational angle of the crankshaft 26 reached the specific angle. Therefore, there is no need to periodically receive data on the rotational angle of the crankshaft 26 from the control unit 5 of the press device 2. As a result, as shown in FIG. 12 , the controller 40B can independently control the air cylinders 211, 221, and 231 without being connected to the control unit 5.

[0080] The conveying device 1B determines the time Ta at which the rotation angle of the crankshaft 26 reaches a specific angle from the speed of the metal strip 3, but the control unit 5 of the press device 2 may output a specific angle signal indicating that the rotation angle of the crankshaft 26 has reached the specific angle when the rotation angle of the crankshaft 26 reaches the specific angle. The conveying device 1B may then determine the deviation by subtracting the total feed length obtained immediately after the previous specific angle signal from the total feed length obtained immediately after the current specific angle signal.

[0081] (Embodiment 3) In the conveying devices 1A and 1B according to embodiments 1 and 2, the metal strip 3 is simply pressed and tensioned by the tensioners 21-23, but the tension of the metal strip 3 is not measured. The conveying devices 1A and 1B may further include a tension measuring device that measures the tension of the metal strip 3.

[0082] The conveying device 1C according to the third embodiment includes a tension measuring device 60 that is provided between the tensioners 21-23 and the press device 2 and measures the tension of a portion of the metal strip 3 against which the tensioners 21-23 are pressed.

[0083] 13 to 15, a conveyance device 1C according to the third embodiment will be described below. In the third embodiment, the configuration different from the first and second embodiments will be mainly described.

[0084] Fig. 13 is a right side view of a conveying apparatus 1C according to embodiment 3. Fig. 14 is an enlarged side view of a tension measuring device 60 provided in the conveying apparatus 1C. Fig. 15 is a front view of a movable roll 63 provided in the tension measuring device 60. Note that hatching has been omitted in Fig. 15 to facilitate understanding. Also, the metal strip 3 has been omitted.

[0085] 13, the tension measuring device 60 is provided between the tensioners 21-23 and the press device 2. In this way, the tension measuring device 60 measures the tension of the metal strip 3 applied by the tensioners 21-23.

[0086] Explaining in more detail, as shown in Fig. 14, the tension measuring device 60 has a pair of fixed rolls 61, 62 and a movable roll 63 provided between the fixed rolls 61, 62. In addition, as shown in Fig. 15, the tension measuring device 60 further has a load cell 64 that measures the force applied to the movable roll 63.

[0087] As shown in Fig. 14, the fixed rolls 61 and 62 are arranged apart in the X direction and at the same height in the Z direction. The positions of the shafts 65 and 66 of the fixed rolls 61 and 62 are fixed. The metal strip 3 is wound around the fixed rolls 61 and 62 from the +Z side. As a result, the metal strip 3 is stretched between the fixed rolls 61 and 62.

[0088] In contrast, the movable roll 63 is disposed between the fixed rolls 61 and 62 in the X direction and further in the −Z direction than the fixed rolls 61 and 62. The metal strip 3 is wound around the movable roll 63 from the −Z side. As a result, the movable roll 63 abuts against the metal strip 3 from the +Z side.

[0089] 15, the movable roll 63 has an axis 67 held by a holder 68 that is movable a fixed distance in the Z direction. As a result, when the tension of the metal strip 3 changes, the movable roll 63 moves in the Z direction together with the holder 68. Meanwhile, a load cell 64 is provided on the -Z side of the holder 68, and measures the force applied to the holder 68, which is linked to the movable roll 63. In this way, the load cell 64 measures the force due to the tension of the metal strip 3.

[0090] In detail, as shown in FIG. 14, if the angle of the metal strip 3 wound around the movable roll 63 with respect to the X direction is θ and the tension applied to the metal strip 3 is T, a force F in the +Z direction is applied to the load cell 64 from the metal strip 3, which is expressed by the following equation 2.

[0091]

[0092] Furthermore, if the gravitational acceleration is g and the mass of the movable roll 63 is M, a gravity of Mg acts on the load cell 64 in the −Z direction, and as a result, the load cell 64 measures a load X expressed by the following equation 3.

[0093]

[0094] The load cell 64 transmits the measurement data to the tensioner control unit 48 described in the first embodiment. The tensioner control unit 48 calculates the tension T from the measurement value received from the load cell 64 using the following equation 4.

[0095]

[0096] For example, the tensioner control unit 48 compares the received value of tension T with a threshold value stored in a tension threshold storage unit (not shown), and if the value of tension T is greater than the threshold value, outputs an alarm signal to an alarm (not shown). Alternatively, the tensioner control unit 48 reduces the air pressure in the air cylinders 211, 221, and 233 by a set value. In this way, the tensioner control unit 48 monitors whether or not there is an abnormality in the metal strip 3. Alternatively, if it determines that there is an abnormality in the tension of the metal strip 3, it reduces the tension.

[0097] As described above, the conveying device 1C according to the third embodiment is equipped with a tension measuring device 60 that measures the tension of the metal strip 3, and therefore abnormalities in the conveying device 1C and the press device 2 can be monitored from the tension of the metal strip 3.

[0098] (Embodiment 4) In the conveying devices 1A-1C according to embodiments 1-3, tension is applied to the metal strip 3 by tensioners 21-23. However, the conveying devices 1A-1C are not limited to this, and may further include components or devices that apply tension to the metal strip 3.

[0099] The conveying device 1D according to the fourth embodiment includes an auxiliary tensioner 70 between the tensioners 21-23 and the press device 2.

[0100] A conveyance device 1D according to the fourth embodiment will be described below with reference to Figures 16 and 17. In the fourth embodiment, the configuration different from the first to third embodiments will be mainly described.

[0101] FIG. 16 is a right side view of a transport device 1D according to the fourth embodiment.

[0102] As shown in FIG. 16, the transfer device 1D is provided with an auxiliary tensioner 70 at the entrance of the press device 2 for the metal strip 3, that is, at the entrance on the −X side.

[0103] The auxiliary tensioner 70 is formed in the same shape as the tensioners 21-23 described in the first embodiment, and is disposed in the same manner except for the X position. The auxiliary tensioner 70 is pressed against the metal strip 3 by an air cylinder 71 and a piston rod 72, just like the tensioners 21-23.

[0104] Unlike the tensioners 21-23, the auxiliary tensioner 70 applies pressure while the press device 2 is performing press processing. Figure 17 shows the transition of the pressure forces of the tensioners 21-23 and the auxiliary tensioner 70.

[0105] FIG. 17 is a graph showing an example of the transitions in the position of the slide 28 of the press device 2, the total feed length of the metal strip 3 by the conveying device 1D, the feed speed of the metal strip 3 by the conveying device 1D, and the pressing forces of the tensioners 21-23 and the auxiliary tensioner 70 on the metal strip 3. The rotation angle θb of the crankshaft 26 shown in FIG. 17 refers to the rotation angle of the crankshaft 26 when the slide 28 of the press device 2 moves from top dead center P1 toward bottom dead center P2 and slightly before the hitch feeder 30 finishes feeding the metal strip 3. In the "Pressing Force" graph in FIG. 17, the transitions in the pressing forces of the tensioners 21-23 are shown by solid lines, and the transitions in the pressing force of the auxiliary tensioner 70 are shown by dotted lines. Furthermore, in this graph, the transitions in the total pressing forces of the tensioners 21-23 and the auxiliary tensioner 70 are shown by dashed lines.

[0106] As described in the first embodiment, the hitch feeder 30 feeds the metal strip 3 by inserting pins 31 into through holes 301 formed in the metal strip 3 and moving the pins 31 in this state. In the hitch feeder 30, when the feed speed of the metal strip 3 shown in FIG. 17 increases with an increase in the processing speed of the press device 2, the acceleration and inertial force also increase. As a result, the pins 31 hit the inner walls of the through holes 301 hard, applying large stress to the peripheral edges of the through holes 301. This may result in deformation of the through holes 301. For example, if the hitch feeder 30 feeds the metal strip 3 at high speed for an intermittent feed and then stops the metal strip 3, a large inertial force may be applied to the metal strip 3, resulting in deformation of the through holes 301 by the pins 31. Such deformation of the through-hole 301 is particularly likely to occur when the thickness of the metal strip 3 is small, for example, 0.05 to 0.50 mm.

[0107] Therefore, in order to prevent the through hole 301 from being deformed by the inertial force generated by deceleration when the metal strip 3 is stopped, the auxiliary tensioner 70 presses from when the feed speed starts to decrease until before the feed speed starts to increase after reaching 0, as shown in the graph of "Feed Speed ​​of Metal Strip 3" in Fig. 17. In other words, the auxiliary tensioner 70 presses from when the crankshaft 26 is at a rotation angle θb, which is the state before press working, to when the crankshaft 26 is at a rotation angle θc, which is the state after press working.

[0108] Furthermore, the force with which the auxiliary tensioner 70 is pressed against the metal strip 3 is, for example, 50% of the force with which the tensioners 21-23 are pressed against the metal strip 3. More specifically, the force with which the tensioners 21-23 are pressed against the metal strip 3 is adjusted by the tensioner control unit 48, as described in the first embodiment. As shown in the graph of "Pressing Force" in FIG. 17 , the forces F1 and F2 with which the auxiliary tensioner 70 is pressed against the metal strip 3 are, for example, 50% of the pressing forces F3 and F4 of the tensioners 21-23 immediately before the auxiliary tensioner 70 starts to press against the metal strip 3. As a result, as shown by the dashed line in the "pressing force" graph in Fig. 17, the metal strip 3 is pressed by both the tensioners 21-23 and the auxiliary tensioner 70 with a force greater than the pressing force of the tensioners 21-23 alone, as shown by the solid line in the "pressing force" graph in Fig. 17, during the period from when the crankshaft 26 is at rotation angle θb to when it is at rotation angle θc. In this way, the auxiliary tensioner 70 prevents the through hole 301 from being deformed by the inertial force generated by the deceleration of the feed speed.

[0109] In this way, the auxiliary tensioner 70 is pressed against the metal strip 3 from the time the feed speed of the hitch feeder 30 is decelerated until it is accelerated again, preventing movement of the metal strip 3. As a result, the auxiliary tensioner 70 improves the accuracy of the press working.

[0110] As described above, the conveying device 1D according to the fourth embodiment includes the auxiliary tensioner 70 that holds down the metal strip 3 during press working. Therefore, the press device 2 has high processing accuracy during press working of the metal strip 3.

[0111] (Embodiment 5) In the conveying devices 1A-1D according to embodiments 1-4, the controllers 40A, 40B calculate the deviation between the actual feed length and the set length of the metal strip 3, and control the tensioners 21-23 to press against the metal strip 3 with a pressing force based on the deviation. However, the controllers 40A, 40B are not limited to this. In certain cases, the controllers 40A, 40B may use feedforward control to control the force with which the tensioners 21-23 press against the metal strip 3.

[0112] The conveying device 1E according to the fifth embodiment includes a controller 40E that controls the force with which the tensioners 21-23 press the metal strip 3 by feedforward control when the processing speed of the press device 2 changes from a constant value.

[0113] 18 to 21, a conveyance device 1E according to the fifth embodiment will be described below. In the fifth embodiment, the configuration different from the first to fourth embodiments will be mainly described.

[0114] Fig. 18 is a block diagram of a controller 40E included in the transport device 1E. Fig. 19 is a diagram showing an example of the configuration of a database 590 stored in a database storage unit 59 of the controller 40E.

[0115] As shown in FIG. 18, the controller 40E includes a feed length measuring unit 57, a tensioner control unit 58, and a database storage unit 59 to perform feedforward control when the processing speed of the press device 2 changes from a constant value.

[0116] The feed length measuring unit 57 has the same configuration and function as the feed length measuring unit 47 described in embodiment 1. As a result, the feed length measuring unit 57 receives data on the displacement and speed of the metal strip 3 periodically transmitted from the length measuring sensor 50. The feed length measuring unit 57 transmits the received data on the speed of the metal strip 3 to the tensioner control unit 58.

[0117] The press apparatus 2 shown in FIG. 1 may vary the processing speed during press working, i.e., the number of press operations per fixed time, e.g., the number of press operations per minute. To explain this in detail, for example, when performing high-speed press working, the press apparatus 2 may gradually increase the processing speed immediately after the start of press working. In this case, the press apparatus 2 may gradually increase the processing speed to a fixed value and then gradually decrease the processing speed before the end of press working. When changing the processing speed in the press apparatus 2, the control unit 5 shown in FIG. 18 sends processing speed data to the controller 40E to change the transport speed of the metal strip 3 by the hitch feeder 30.

[0118] Like the controller 40A described in the first embodiment, the controller 40E controls a drive device (not shown) that drives the movable block 32 of the hitch feeder 30. When the controller 40E receives processing speed data from the control unit 5 of the press apparatus 2, the controller 40E controls the drive device (not shown) of the hitch feeder 30 based on the processing speed data. As a result, the controller 40E operates the movable block 32 of the hitch feeder 30 at a speed corresponding to the processing speed data of the press apparatus 2. As a result, the controller 40E changes the transport speed of the metal strip 3 by the hitch feeder 30.

[0119] Furthermore, when the control unit 5 of the press apparatus 2 shown in FIG. 18 changes the above-mentioned machining speed, it outputs a machining speed change signal indicating that the machining speed is changing, and transmits the machining speed change signal to the above-mentioned tensioner control unit 58 of the controller 40E.

[0120] When the control unit 5 of the press machine 2 outputs a processing speed change signal, the tensioner control unit 58 receives the processing speed change signal. The tensioner control unit 58 also receives data on the speed of the metal strip 3 from the feed length measurement unit 57. When the tensioner control unit 58 receives the processing speed change signal, it controls the force with which the tensioners 21-23 press against the metal strip 3 based on the database stored in the database storage unit 59 and the received data on the speed of the metal strip 3. This is because, when a processing speed change signal is received, i.e., when the conveyance speed of the metal strip 3 changes, if the pressing forces of the tensioners 21-23 are controlled by the PID control described in the first embodiment, in other words, by feedback control, the control of the tensioners 21-23 may not be able to keep up. As a result, feedforward control is desirable.

[0121] 19 is stored in the database storage unit 59. The database 590 stores data experimentally determined from past processing data of the press apparatus 2. The database 590 associates data sets of the type of material, thickness, and surface treatment of the material processed by the press apparatus 2, and the processing speed of the press apparatus 2 with data on the air pressure of the air cylinders 211, 221, and 231 that has been experimentally verified to achieve an appropriate pressing force of the tensioners 21-23 under the conditions indicated by the data.

[0122] When the tensioner control unit 58 receives the processing speed change signal, it reads out a database 590 from the database storage unit 59 shown in FIG. 18 . The tensioner control unit 58 also calculates the processing speed of the press apparatus 2 from the data on the speed of the metal strip 3 received from the feed length measurement unit 57. As shown in FIG. 18 , the input device 29 is connected to the controller 40E. The tensioner control unit 58 acquires data on the material type, thickness, and surface treatment of the material to be processed by the press apparatus 2, which data is input from the input device 29. The tensioner control unit 58 then selects, from the data sets for each condition number contained in the read database 590, the data set that matches or is most similar to the data set configured of the calculated processing speed and the acquired material type, thickness, and surface treatment.

[0123] In addition, the tensioner control unit 58 may calculate the ratio of the machining speed included in the data set to the calculated machining speed, and multiply the air pressure value included in the data set by the calculated ratio to obtain the air pressure, and use the obtained air pressure as the air pressure of the selected data set.

[0124] The tensioner control unit 58 controls the electropneumatic regulators 213, 223, and 233 to adjust the air pressure of the air cylinders 211, 221, and 231 to the air pressure associated with the selected data set in the database 590. As a result, the tensioner control unit 58 presses the tensioners 21-23 against the metal strip 3 with a pressing force based on the database 590. As a result, the tensioner control unit 58 adjusts the frictional force when the metal strip 3 is fed. In this way, the tensioner control unit 58 feeds the metal strip 3 with high precision even when the processing speed of the press device 2 is changed.

[0125] Next, a method for controlling the tensioners 21-23 by the controller 40E will be described in detail with reference to Figures 20 and 21. In the following description, it is assumed that the press apparatus 2 and the transport device 1E are started by pressing a start button (not shown) provided on the press apparatus 2, as described in the first embodiment.

[0126] Fig. 20 is a flowchart of the switching process performed by the controller 40E. Fig. 21 is a flowchart of the second tensioner control process performed by the controller 40E.

[0127] When a start button (not shown) provided on the press apparatus 2 is pressed to start the press apparatus 2 and the transport apparatus 1E, the CPU 41 of the transport apparatus 1E executes a switching program for switching between PID control and feedforward control. As a result, the switching process flow shown in FIG. 20 is started. In the switching process flow, first, the controller 40E determines whether a processing speed change signal is being output from the control unit 5 of the press apparatus 2 (step S11).

[0128] If the controller 40E determines that it has not received a machining speed change signal from the control unit 5 of the press apparatus 2 and that no machining speed change signal has been output (No in step S11), the machining speed of the press apparatus 2 remains constant, and therefore the controller 40E executes the first tensioner control process described in embodiment 1 (step S12). Then, the controller 40E executes a series of steps from step S1 to step S7 of the first tensioner control process shown in FIG. 9, and then returns to step S11 shown in FIG. 20. This prepares for the control unit 5 to output a subsequent machining speed change signal.

[0129] On the other hand, when the controller 40E receives the machining speed change signal from the control unit 5 of the press device 2 and determines that the machining speed change signal is being output (Yes in step S11), the controller 40E executes the second tensioner control process shown in FIG. 21 (step S13).

[0130] 21, the controller 40E first reads the database 590 (step S21). Specifically, the tensioner control unit 58 of the controller 40E reads the database 590 stored in the database storage unit 59.

[0131] Next, the tensioner control unit 58 acquires current speed data of the metal strip 3 (step S22). In detail, as described above, the feed length measurement unit 57 periodically receives data on the displacement and speed of the metal strip 3 from the length measurement sensor 50 and transmits the received data on the displacement and speed of the metal strip 3 to the tensioner control unit 58. The tensioner control unit 58 acquires the most recent speed data from the received speed data of the metal strip 3 as the current speed data.

[0132] After acquiring the current speed data of the metal strip 3, the tensioner control unit 58 uses the acquired speed data of the metal strip 3 to calculate the processing speed of the press device 2 (step S23). For example, a relational expression between the speed of the metal strip 3 and the processing speed of the press device 2 is determined in advance by experiment, and the tensioner control unit 58 uses this relational expression to calculate the current processing speed of the press device 2 from the current speed data of the metal strip 3.

[0133] Next, the tensioner control unit 58 acquires various data input from the input device 29 (step S24). The various data here refers to the data on the conditions included in the data set of the database 590 read out in step S21, and specifically refers to data on the type of material, thickness, and surface treatment of the material to be processed by the press device 2.

[0134] When the tensioner control unit 58 acquires the various data input from the input device 29, it selects a data set from the data sets in the database 590 read out in step S21 that matches or approximates the acquired various data and the machining speed calculated in step S23 (step S25). For example, if the various data input from the input device 29 indicates that the material type is B, the plate thickness is 0.09, the surface treatment is normal, and the calculated machining speed is 250, then it selects the data set with condition number "2" from the data sets in the database 590 shown in FIG. 19 as the matching data set.

[0135] Returning to FIG. 21 , once the tensioner control unit 58 has selected a data set, it adjusts the electro-pneumatic regulator based on the air pressure data of the selected data set (step S26). For example, if the data set selected from the data sets is the data set with condition number "2," the tensioner control unit 58 adjusts the electro-pneumatic regulator to the air pressure data value "10.0 kgf" included in the data set with condition number "2." This causes the tensioner control unit 58 to adjust the air pressures of the air cylinders 211, 221, and 231 to the air pressure data value of the selected data set. As a result, the tensioner control unit 58 presses the tensioners 21-23 against the metal strip 3 with an appropriate pressing force, thereby adjusting the frictional force when the metal strip 3 is fed. As a result, the metal strip 3 is fed with high precision.

[0136] After executing the series of steps from step S21 to step S26, the tensioner control unit 58 ends the second tensioner control process. Then, the process returns to step S11 of the switching process shown in FIG. 20 . This causes the controller 40E to prepare for a change in the output of the machining speed change signal by the control unit 5. For example, the controller 40E prepares for a case where the output of the machining speed change signal is stopped. The controller 40E then repeats steps S11-S13 of the switching process to adjust the pressing force of the tensioners 21-23 against the metal strip 3, both when the press device 2 changes the machining speed and when the press device 2 does not change the machining speed, thereby feeding the metal strip 3 with high precision.

[0137] The above-mentioned processing speed change signal is an example of a signal indicating a change in the press processing speed as defined in the present disclosure. Also, the above-mentioned database storage unit 59 is an example of a storage unit that stores a database as defined in the present disclosure.

[0138] As described above, in the conveyance device 1E according to the fifth embodiment, when the controller 40E receives a processing speed change signal from the press device 2, it reads out the database 590 from the database storage unit 59 and acquires speed data of the metal strip 3 from the length measurement sensor 50. The controller 40E then determines the force with which the tensioners 21-23 press against the metal strip 3 based on the read database 590 and the acquired speed data, and controls the tensioners 21-23 with the determined pressing force. Therefore, even when the processing speed of the press device 2 is changing, the conveyance device 1E can adjust the pressing force of the tensioners 21-23 against the metal strip 3 and feed the metal strip 3 with high precision.

[0139] The above describes the conveying device 1A-1E, the press machine system, and the control method for the conveying device 1A-1E according to the embodiment of the present disclosure, but the control methods for the conveying device 1A-1E, the press machine system, and the conveying device 1A-1E are not limited to this.

[0140] For example, in the first to fifth embodiments, the object to be formed by the press device 2 is a fin of a heat exchanger, but the object to be formed by the press device 2 is not limited to this. The object to be formed by the press device 2 may be a strip, for example, a metal strip 3.

[0141] In embodiment 1-5, the conveying device 1A-1E is equipped with a hitch feeder 30, but the conveying device 1A-1E is not limited to this. The conveying device 1A-1E may be equipped with a feeding device that intermittently feeds a set length of the strip to the press device 2 each time press working is completed. Therefore, the hitch feeder 30 may be a gripper feeder that is such a feeding device.

[0142] In embodiments 1-5, a press system including a press 2 and conveying devices 1A-1E forms and conveys fin members. This press system may further include a cutting device that cuts the metal strip 3 in the width direction to manufacture fins. The manufactured fins may also be used in the manufacture of heat exchangers.

[0143] As described above, the control methods of the conveying devices 1A-1E, the press machine system, and the conveying devices 1A-1D are not limited to the above-described embodiments, and various modifications and substitutions can be made. Various embodiments of the present disclosure are described below as appendices.

[0144] (Supplementary Note 1) A conveying device comprising: a feed device that intermittently conveys a strip by a set length to a press device each time press working is completed; a pressing device that generates tension on the strip by pressing a tensioner against the strip while the feed device is conveying the strip, and slows down the speed of the strip conveyed by the feed device; a measuring unit that measures the length of the strip actually fed by the feed device from a previous specific press state to a current specific press state each time the press device reaches a specific press state during the press working; and a control unit that calculates a deviation between the actual feed length of the strip measured by the measuring unit and the set length, and controls the force with which the pressing device presses the tensioner against the strip based on the deviation. (Supplementary Note 2) The conveying device according to Supplementary Note 1, wherein the press device has a crankshaft that operates a slide mechanism to apply pressure to the strip, and the specific press state is a state in which the crankshaft is at a specific angle. (Supplementary Note 3) The conveying device according to Supplementary Note 2, wherein the measurement unit comprises: a length measurement unit that periodically measures a total feed length of the strip that has been fed by the feed device to the press device during press working up to that point; a speed measurement unit that periodically measures the speed of the strip; and a calculation unit that determines the most recent time at which the crankshaft reached the specific angle and the time immediately preceding that time from the speed measured by the speed measurement unit, and determines the actual feed length from the total feed length at the most recent time measured by the length measurement unit and the total feed length at the time immediately preceding that time. (Supplementary Note 4) The conveying device according to any one of Supplements 1 to 3, wherein the control unit determines a force that presses the tensioner against the strip by PID control. (Supplementary Note 5) The conveying device according to any one of Supplements 1 to 4, further comprising a tension measurement device that measures the tension of the strip.(Supplementary Note 6) The tension measuring device comprises: a pair of fixed rolls whose rotation axes are fixed in position, with the strip wrapped around them from above to support the strip from below, a movable roll that contacts from above the portion of the strip wrapped between the pair of fixed rolls and moves up and down as the tension of the strip changes, and a load cell that measures the force applied to the movable roll by the strip, and the load cell outputs a measured value to the control unit. (Supplementary Note 7) The conveying device according to any one of Supplementary Notes 1 to 6, further comprising an auxiliary tensioner that contacts the strip and generates tension on the strip while the press device starts and finishes pressing. (Supplementary Note 8) A conveying device as described in any one of Supplementary Notes 1 to 7, further comprising a memory unit that stores a database in which data on the speed at which the feed device conveys the strip is associated with data on the pressing force of the tensioner on the strip at that speed, wherein the measurement unit has a speed measurement unit that periodically measures the speed of the strip, wherein the press device outputs a signal indicative of the change in the press working speed when the press working speed changes from a constant value, and wherein the control unit, when receiving the signal from the press device, reads out the database from the memory unit and acquires data on the speed of the strip from the speed measurement unit, and determines and controls the force with which the tensioner presses the strip based on the read database and the acquired speed data, and when not receiving the signal from the press device, determines a deviation between the actual feed length of the strip measured by the measurement unit and the set length, and controls the force with which the pressing device presses the tensioner on the strip based on the deviation. (Supplementary Note 9) A press system comprising: the conveying device according to any one of Supplementary Notes 1 to 8; and the press.(Supplementary Note 10) A control method for a conveying device comprising: a feeding device that intermittently conveys a strip by a set length to a press device each time press processing is completed; a pressing device that presses a tensioner against the strip while the feeding device is conveying the strip, thereby generating tension in the strip and slowing down the speed of the strip conveyed by the feeding device; and a measuring unit that measures the length of the strip fed by the feeding device, comprising the steps of: acquiring data on the feed length of the strip from the measuring unit; and measuring the length of the strip actually fed by the feeding device from a previous specific press state to a current specific press state each time the press device reaches a specific press state during press processing; and determining a deviation between the actual feed length of the strip obtained in the step of measuring the actual feed length and the set length, and controlling the force with which the pressing device presses the tensioner against the strip based on the deviation.

[0145] The present disclosure allows various embodiments and modifications without departing from the broad spirit and scope of the present disclosure. Furthermore, the above-described embodiments are intended to explain the present disclosure and do not limit the scope of the present disclosure. That is, the scope of the present disclosure is defined by the claims, not the embodiments. Various modifications made within the scope of the claims and within the meaning of the disclosure equivalent thereto are considered to be within the scope of the present disclosure.

[0146] This application is based on Japanese Patent Application No. 2023-60464, filed on April 3, 2023. The entire specification, claims, and drawings of Japanese Patent Application No. 2023-60464 are incorporated herein by reference.

[0147] 1A-1E Conveying device, 2 Press device, 3 Metal strip, 4 Coil, 5 Control unit, 10 Uncoiler, 11, 12 Pinch roll, 13 Leveler, 21-23 Tensioner, 24 Stage, 25 Die, 26 Crankshaft, 27 Connecting rod, 28 Slide, 29 Input device, 30 Hitch feeder, 31 Pin, 32 Movable block, 40A, 40B, 40E Controller, 41 CPU, 42 Memory, 43 Feed length data storage unit, 44 Set length data storage unit, 45 Angle data storage unit, 46 I / O port, 47 Feed length measurement unit, 48 Tensioner control unit, 49 Threshold data storage unit, 50 Length measurement sensor, 57 Feed length measurement unit, 58 Tensioner control unit, 59 Database storage unit, 60 Tension measurement device, 61, 62 Fixed roll, 63 Movable roll, 64 load cell, 65-67 shaft, 68 holder, 70 auxiliary tensioner, 71 air cylinder, 72 piston rod, 211, 221, 231 air cylinder, 212, 222, 232 piston rod, 213, 223, 233 electro-pneumatic regulator, 261 main shaft, 262 crank pin, 301 through hole, 311 cylindrical portion, 312 compression coil spring, 590 database, A axis, C clockwise, D directly upward, F, F1-F4 force, P1 top dead center, P2 bottom dead center, T tension, X load, θa, θb, θc angle.

Claims

1. A feeding device that intermittently conveys a strip by a set length to a press device every time press working is completed, a pressing device that generates tension in the strip by pressing a tensioner against the strip when the feeding device is conveying the strip, and that decelerates the speed of the strip by the feeding device, a measuring unit that measures the length that the feeding device has actually fed the strip during the period from the previous specific press state to the current specific press state every time the press device reaches a specific press state during the press working, and that periodically measures the speed of the strip, a control unit that obtains a deviation from the actual feeding length of the strip measured by the measuring unit and the set length, and controls the force with which the pressing device presses the tensioner against the strip based on the deviation, a storage unit that stores a database in which data on the speed of the strip when the feeding device conveys the strip is associated with data on the pressing force of the tensioner against the strip at that speed, comprising: the control unit: when the speed of the press working changes from a constant value, obtains data on the speed of the strip from the measuring unit, determines the force with which the tensioner presses against the strip based on the database and the obtained speed data, and controls the force, when the speed of the press working does not change from a constant value, obtains a deviation from the actual feeding length of the strip measured by the measuring unit and the set length, and controls the force with which the pressing device presses the tensioner against the strip based on the deviation. A conveying device

2. The press device includes a crankshaft that operates a slide mechanism for pressing the strip, and the specific press state is a state in which the crankshaft is at a specific angle. The conveying device according to claim 1

3. The measuring unit: a length measuring unit that periodically measures the total feeding length that the feeding device has fed the strip to the press device during the press working up to that point, a speed measuring unit that periodically measures the speed of the strip, and an arithmetic unit that obtains the time closest to when the crankshaft reaches the specific angle and the time immediately before that from the speed measured by the speed measuring unit, and obtains the actual feeding length from the total feeding length at the time closest to the time obtained and the total feeding length at the time immediately before that measured by the length measuring unit. Comprising ​ ​ The conveying device according to claim 2.

4. The control unit determines the force for pressing the tensioner against the belt-like body by PID control. The conveying device according to claim 1.

5. The conveying device further includes a tension measuring device for measuring the tension of the belt-like body. The conveying device according to claim 1.

6. The tension measuring device A pair of fixed rolls with the position of the rotating shaft fixed, around which the belt-like body is wound from above to support the belt-like body from below, A movable roll that abuts on the portion of the belt-like body wound between the pair of fixed rolls from above and moves up and down as the tension of the belt-like body changes, A load cell for measuring the force applied to the movable roll by the belt-like body, Comprises, The load cell outputs the measured value to the control unit. The conveying device according to claim 5.

7. The conveying device further includes an auxiliary tensioner that abuts on the belt-like body and generates tension in the belt-like body until the press device starts and ends the press working. The conveying device according to claim 1.

8. The conveying device according to any one of claims 1 to 7, The press device, A press device system comprising.

9. A feeding device that intermittently conveys the belt-like body to the press device by a set length every time the press working is completed, A pressing device that generates tension in the belt-like body by pressing a tensioner against the belt-like body when the feeding device is conveying the belt-like body, and decelerates the speed of the belt-like body by the feeding device, A measuring unit that measures the length of the belt-like body fed by the feeding device and periodically measures the speed of the belt-like body, A storage unit that stores a database in which data on the force of pressing the tensioner against the belt-like body at the speed is associated with the data on the speed of the belt-like body when the feeding device conveys the belt-like body, A control method for a conveying device comprising: A first step of acquiring data on the feeding length of the belt-like body from the measuring unit, and measuring the actual length of the belt-like body conveyed by the feeding device between the previous specific press state and the current specific press state every time the press device reaches a specific press state in the press working, A second step of acquiring data on the speed of the belt-like body from the measuring unit, determining the force for pressing the tensioner against the belt-like body based on the database and the acquired data on the speed, and controlling the force. A third step of obtaining a deviation from the actual feed length of the strip obtained in the first step and the set length, and controlling the force with which the pressing device presses the tensioner against the strip based on the deviation; comprising; when the speed of the pressing process changes from a constant value, performing the second step; when the speed of the pressing process does not change from a constant value, performing the third step; A control method for a conveying device.