Position control device and position control method

Abstract

To control automatically a position of a roll relative to a T-die.SOLUTION: A position control device 100 includes: a camera 10 that images a T-die 103 and a one end surface 1a of a molding roll 1 in an axial direction; a control device 30 that acquires a target image captured by the camera 10; and a movement mechanism 40 for moving the molding roll 1. The control device 30 performs image processing on the target image to detect an outer shape of the T-die 103 and the one end surface 1a of the roll, and obtains a relative position of the roll with respect to the T-die 103 from the detected outer shape of the T-die 103 and the one end surface 1a of the roll, and obtains an amount of movement of the roll from a target position and the relative position of the roll, and outputs a movement command to the movement mechanism 40 to move the roll by the calculated amount of movement.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a position control device and a position control method for controlling the position of a roll that conveys a sheet discharged from a T-die. [Background technology]

[0002] Patent Document 1 discloses a sheet / film manufacturing apparatus comprising an extruder, a T-die, and a casting machine, in which a sheet- or film-shaped molten resin is extruded from the T-die toward the casting machine. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2020-75476 Summary of the Invention [Problem to be solved by the invention]

[0004] In the sheet / film manufacturing apparatus of Patent Document 1, the sheet extruded from the T-die is transported by the rolls of a casting machine. Typically, the position of the T-die can shift due to the thermal expansion of the extruder and the influence of the ambient temperature environment. For this reason, when transporting the sheet using the casting machine, a positioning operation is performed in which the rolls are brought close to the T-die and positioned at a predetermined relative position. By appropriately positioning the rolls relative to the T-die, the accuracy of the thickness of the transported sheet is ensured. Conventionally, the positioning operation of bringing the rolls of the casting machine close to the T-die has been performed visually and manually by an operator. Therefore, there is a need to automate the positioning operation.

[0005] The present invention has been made in consideration of the above problems, and aims to provide a position control device and a position control method that automatically position the roll in a casting machine. [Means for solving the problem]

[0006] According to one aspect of the present invention, a position control device includes an imaging unit that images the T-die and one end surface of the roll in the axial direction, a control unit that acquires the target image captured by the imaging unit, and a movement mechanism that moves the roll. an illumination unit that illuminates one end surface of the roll; the control device applies image processing to the target image to detect the outlines of the T-die and one end surface of the roll, obtains the relative position of the roll with respect to the T-die from the detected outlines of the T-die and one end surface of the roll, obtains the movement amount of the roll from the target position to which the roll is to be moved and the relative position, and outputs a movement command to the movement mechanism to move the roll by the movement amount. death , The lighting unit is provided in the inner region of a virtual cylindrical surface that is an extension of the outer circumferential surface of the roll along the central axis of the roll. .

[0007] According to another aspect of the present invention, a position control method includes: an illumination unit provided in an inner region of an imaginary cylindrical surface obtained by extending the outer peripheral surface of the roll along the central axis of the roll, illuminating one end surface of the roll in the axial direction; The imaging unit detects the T-die and roll one The image of the target object captured by the imaging unit is image-processed to detect the outer shapes of the T-die and one end face of the roll, the relative position of the roll with respect to the T-die is obtained from the detected outer shapes of the T-die and one end face of the roll, the amount of movement of the roll is obtained from the target position to which the roll is to be moved and the relative position, and the roll is moved by the amount of movement using the movement mechanism. [Effects of the Invention]

[0008] According to this aspect, the relative position of the roll with respect to the T-die is acquired based on the image captured by the imaging unit, and the amount of movement of the roll to the target position can be calculated based on the relative position. Then, the movement mechanism is controlled to move the roll by the calculated amount of movement. This allows the roll to be automatically positioned. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a block diagram showing the overall configuration of a film manufacturing apparatus according to an embodiment of the present invention. [Figure 2] FIG. 1 is a front view showing a T-die and a casting machine according to an embodiment of the present invention. [Figure 3]1 is a block diagram showing a configuration of a position control device according to an embodiment of the present invention; [Figure 4] 1 is a perspective view showing a configuration of a position control device according to an embodiment of the present invention; [Figure 5] 1 is a side view showing a configuration of a position control device according to an embodiment of the present invention; [Figure 6] 3 is a flowchart illustrating a position control method according to an embodiment of the present invention. [Figure 7] 10 is a flowchart showing a contact prevention process of a position control method according to an embodiment of the present invention. [Figure 8] 1A and 1B are diagrams schematically showing a target image in a position control method according to an embodiment of the present invention; DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, a position control device 100 according to an embodiment of the present invention will be described with reference to the drawings. Note that in each drawing, the scale of each component has been appropriately changed for the sake of convenience of explanation, and the illustrations are not necessarily precise. Furthermore, for multiple identical components, only some of them may be assigned reference numerals, and the reference numerals for the others may be omitted.

[0011] The position control device 100 is applied to a film manufacturing apparatus 1000 for producing stretched film products.

[0012] 1, the film production apparatus 1000 includes a raw material supply device 101, an extruder 102, a T-die 103, a casting machine 104, and a longitudinal stretching machine 105. Since the raw material supply device 101, the extruder 102, the T-die 103, and the longitudinal stretching machine 105 can each adopt a known configuration, detailed illustrations and descriptions thereof will be omitted and only a brief description will be given below.

[0013] The raw material supply device 101 is supplied with raw materials (for example, resin and plasticizer) for the film product, and supplies the supplied raw materials to the extruder 102.

[0014] The extruder 102 melts and kneads the raw materials supplied from the raw material supply device 101 and supplies the melted raw materials to a T-die 103. The extruder 102 is, for example, a single-screw extruder having one screw. However, the extruder 102 may also be a twin-screw kneading extruder.

[0015] The T-die 103 extrudes the molten material supplied from the extruder 102 from a slit (not shown) to form it into a sheet (strip).

[0016] The casting machine 104 cools and solidifies the sheet continuously discharged from the T-die 103. The configuration of the casting machine 104 will be described in detail later. The sheet cooled and solidified by the casting machine 104 is guided to the longitudinal stretching machine 105.

[0017] The longitudinal stretching machine 105 stretches the sheet in the longitudinal direction, which is the conveying direction, to reduce the thickness and produce a film product.

[0018] Next, the configuration of the position control device 100 will be described with reference to FIGS.

[0019] As shown in Fig. 2, the casting machine 104 includes multiple rolls that cool and solidify the sheet and transport it downstream. In this embodiment, the casting machine 104 includes rolls such as a forming roll 1 that is rotated by a drive source (not shown) such as a motor, a touch roll 2 that presses the sheet discharged from the T-die 103 against the forming roll 1, and a transport roll 3 that is rotated by the drive source and transports the sheet led from the forming roll 1. The sheet discharged from the T-die 103 is introduced into the gap between the forming roll 1 and the touch roll 2.

[0020] Each roll is formed in a cylindrical shape and is supported by a support portion 6a on a frame 6. The frame 6 is attached so as to be movable relative to the base 5 in the vertical direction. The base 5 is configured so as to be movable together with the frame 6 in the horizontal direction perpendicular to the central axis of each roll.

[0021] The central axes of the rolls are aligned parallel to one another and perpendicular to the vertical direction (in other words, parallel to the horizontal direction). Hereinafter, the direction in which the rolls are aligned (the left-right direction in FIG. 2) will be referred to as the "adjacent direction." The adjacent direction is a direction perpendicular to the central axes of the rolls and parallel to the horizontal direction. The base 5 is configured to be movable along the adjacent direction.

[0022] The forming roll 1 and the touch roll 2 have similar shapes, and their axial end faces 1a and 2a are located on the same plane. The T-die 103 is located in the axial center of the forming roll 1 and the touch roll 2, above them in the vertical direction (see FIGS. 2 and 5). The T-die 103 has one side face 103a that is located parallel to the end faces 1a and 2a of the forming roll 1 and the touch roll 2. The one side face 103a of the T-die 103 is located closer to the other end faces of the forming roll 1 and the touch roll 2 than the end faces 1a and 2a of the forming roll 1 and the touch roll 2 (see FIG. 5).

[0023] Further, an adjusting plate 25 is attached to the T-die 103 as an adjusting part having a positioning surface 25a whose position in the axial direction of the forming roll 1 is the same as that of one end surface 1a of the forming roll 1. In other words, the positioning surface 25a of the adjusting plate 25 is provided on the same plane as one end surfaces 1a, 2a of the forming roll 1 and the touch roll 2. The shapes of the forming roll 1, the touch roll 2, the T-die 103, and the adjusting plate 25 are stored in advance in a control device 30, which will be described later.

[0024] As shown mainly in Figures 3 and 4, the position control device 100 comprises a camera 10 as an imaging unit that images the T-die 103 and one end surface 1a, 2a of the forming roll 1 and the touch roll 2 in the axial direction, a light 20 as an illumination unit that illuminates one end surface 1a of the forming roll 1, a control device 30 that acquires the target image captured by the camera 10, and a moving mechanism 40 that moves each roll via a frame 6.

[0025] The camera 10 is provided at a position where it can capture images of one side surface 103a of the T-die 103 and one end surfaces 1a, 2a of the forming roll 1 and touch roll 2 in the axial direction. More specifically, the camera 10 is provided at one end side of the forming roll 1 in the axial direction, spaced apart from one end surface 1a of the forming roll 1, with its optical axis parallel to the axial direction of the forming roll 1. The camera 10 continuously captures images of the T-die 103, the forming roll 1, and the touch roll 2 to obtain image data in the form of a video. The camera 10 may also be capable of intermittently capturing still images. The image data obtained by the camera 10 is input to the control device 30.

[0026] The light 20 has an internal light source and is provided so as to irradiate one end surface 1a of the forming roll 1 with light from the light source. Specifically, as shown in FIG. 5, the light 20 is provided so that at least a portion of the light source is included within the range inside an imaginary cylindrical surface (indicated by a two-dot chain line in FIG. 5) obtained by extending the outer circumferential surface of the forming roll 1 in the axial direction of the forming roll 1. Furthermore, the light 20 is provided so that its optical axis is parallel to the central axis of the forming roll 1 (coaxial in this embodiment). Therefore, in this embodiment, the optical axis of the light 20 intersects with one end surface 1a of the forming roll 1. This allows light to be irradiated onto the entire outer circumferential edge of one end surface 1a of the forming roll 1.

[0027] Any light source can be used for the light 20, such as an incandescent lamp, a fluorescent lamp, an LED, etc. The light 20 may also be of any of a diffusing type, a concentrating type, and a directional type.

[0028] The movement mechanism 40 has a translation mechanism 41 that moves the base 5 and the platform 6 in the adjacent direction, and an elevation mechanism 45 that moves the platform 6 in the vertical direction. Based on a command signal from the control device 30, the movement mechanism 40 moves the base 5 and the platform 6, and ultimately the forming roll 1, to desired positions in the adjacent direction and vertical direction.

[0029] The translation mechanism 41 has an electric motor 42, which is, for example, a servo motor, and a ball screw mechanism 43 that converts the rotation of the electric motor 42 into linear motion. Wheels 7 are attached to the platform 6, and the wheels 7 are placed on rails 8 that extend in the adjacent direction. The platform 6 is moved in the adjacent direction by the translation mechanism 41 while being guided by the rails 8.

[0030] The lifting mechanism 45 has a plurality of jacks 46 that vertically lift and lower the platform 6 relative to the base 5. The plurality of jacks 46 are operated synchronously by the control device 30.

[0031] The control device 30 is composed of a microcomputer equipped with a CPU (Central Processing Unit), ROM (Read Only Memory), RAM (Random Access Memory), and I / O interface (Input / Output Interface). The RAM stores data for CPU processing, the ROM stores CPU control programs and the like in advance, and the I / O interface is used for inputting and outputting information to and from connected devices. The control device 30 is programmed to be able to execute at least the processes necessary to execute the control according to this embodiment and the modified examples. The control device 30 may be configured as a single device, or may be divided into multiple devices and configured so that each control is processed in a distributed manner by the multiple devices.

[0032] The control device 30 controls the operation of each component of the position control device 100 so as to enable the position control method described in this specification. The control device 30 is not limited to being dedicated to the position control device 100, but may be shared with other devices in the film manufacturing apparatus 1000.

[0033] Next, a roll position control method using the position control device 100 will be described.

[0034] In this embodiment, the position of the forming roll 1 relative to the T-die 103 is used as a reference to control the position of the roll.

[0035] Fig. 6 is a flowchart showing a position control method executed by the control device 30. When an operator inputs an operation, the control device 30 executes the process shown in Fig. 6. Based on the operator's operation, the camera 10 outputs a video of the T-die 103 including the adjustment plate 25 and the forming roll 1 to the control device 30, and the light 20 irradiates one end surface 1a of the forming roll 1 with light.

[0036] In step S10, a target image is acquired from the moving image data input from the camera 10. Specifically, one frame of a still image is extracted from the moving image and acquired as the target image.

[0037] In step S11, image processing is performed on the target image to obtain the outer shapes of the forming roll 1 and the adjusting plate 25 of the T die 103. Specifically, the target image is binarized according to brightness, thereby making it possible to detect the outer shapes of the forming roll 1 and the adjusting plate 25 of the T die 103. Since the detection of the outer shapes of the forming roll 1 and the T die 103 from the target image can be performed by known techniques, detailed explanations will be omitted.

[0038] In step S12, the relative position of the forming roll 1 with respect to the T die 103 is obtained from the outer shape of the adjusting plate 25 of the T die 103 and the outer shape of the forming roll 1 detected from the target image. Since the shapes and positional relationship between the T die 103 and the adjusting plate 25 are stored in advance in the control device 30, the position of the T die 103 can be geometrically calculated from the position of the adjusting plate 25. Then, in step S13, the difference between the target position of the forming roll 1 with respect to the T die 103 inputted in advance to the control device 30 by the operator and the current relative position is calculated to obtain the movement amount of the forming roll 1.

[0039] In step S14, a command signal is output to the movement mechanism 40 to move the pedestal 6 and the base 5 by the movement amount acquired in step S13, and the process ends. As a result, the movement mechanism 40 moves the pedestal 6 and the base 5, and the relative positions of the T-die 103 and the forming roll 1 are adjusted to the target positions. In this way, the position control of the forming roll 1 is performed automatically.

[0040] Furthermore, in the position control device 100, the light 20 irradiates the outer shape (outer edge) of one end surface 1a of the forming roll 1. This increases the brightness of the one end surface 1a of the forming roll 1 in the target image, thereby improving the detection accuracy of the one end surface 1a of the forming roll 1 in image processing by binarization.

[0041] In this embodiment, an adjustment plate 25 having a positioning surface 25a located on the same plane as one end surface 1a of the forming roll 1 is attached to the T-die 103. There is no distance between one end surface 1a of the forming roll 1 and the positioning surface 25a of the adjustment plate 25 with respect to the camera 10, so it is possible to suppress errors in detecting the relative distance based on the outline detected by image processing.

[0042] The control device 30 also has a contact prevention function that prevents contact between the T-die 103 and the forming roll 1. Hereinafter, the contact prevention process that prevents contact will be described with reference to FIG.

[0043] When the position control shown in Fig. 6 is executed, the control device 30 executes the processing shown in Fig. 7 at a predetermined processing interval. In this embodiment, the processing interval of the contact prevention processing shown in Fig. 7 is the same as the time interval between frames of the video captured by the camera 10. In other words, the control device 30 executes the processing shown in Fig. 7 for each frame of the video captured by the camera 10.

[0044] Steps S20 to S22 are the same as steps S10 to S12 in FIG. 6, and therefore a description thereof will be omitted.

[0045] In step S23, the distance between the T-die 103 and the forming roll 1 is calculated from the relative positions of the T-die 103 and the forming roll 1 calculated in step S22.

[0046] In step S24, it is determined whether the distance between the T die 103 and the forming roll 1 calculated in step S23 is below a preset threshold value. This threshold value is the distance at which the T die 103 and the forming roll 1 are spaced apart with a predetermined gap and do not come into contact with each other.

[0047] If it is determined in step S24 that the distance calculated in step S23 is equal to or greater than the threshold, the process ends. If it is determined in step S24 that the distance between the T-die 103 and the forming roll 1 is less than the threshold, a warning signal is output in step S25 and the process ends. That is, as shown in FIG. 8, a warning signal is output when a virtual outer circumferential surface (broken line in the drawing) offset radially outward from the outer circumferential surface of the forming roll 1 comes into contact with the T-die 103. The offset amount of the virtual outer circumferential surface is set by a threshold.

[0048] The warning signal is input to, for example, an external monitor or alarm device, which notifies the user that there is a possibility of contact between the T-die 103 and the forming roll 1. Alternatively, a stop signal for stopping the operation of the moving mechanism 40 may be input to the moving mechanism 40 as the warning signal.

[0049] Since the sheet discharged from the T-die 103 is at a high temperature, the temperature of the formed sheet being conveyed also rises. For this reason, even if a target position is input that does not allow the forming roll 1 to come into contact with the T-die 103 at room temperature, the forming roll 1 may become larger in diameter due to thermal expansion, resulting in unintended contact between the T-die 103 and the forming roll 1.

[0050] In this embodiment, by performing the contact prevention process, the worker can recognize the possibility of contact and take measures such as emergency stopping of the movement mechanism 40 to prevent contact between the T-die 103 and the forming roll 1. In this way, unintended contact with the T-die 103 due to thermal expansion of the forming roll 1 can be prevented.

[0051] The effects of this embodiment will be described below.

[0052] The position control device 100 comprises a camera 10 that captures an image of the T die 103 and one end face 1a of the forming roll 1 in the axial direction, a control device 30 that acquires the target image captured by the camera 10, and a movement mechanism 40 that moves the forming roll 1. The control device 30 performs image processing on the target image to detect the outlines of the T die 103 and one end face 1a of the roll, acquires the relative position of the roll with respect to the T die 103 from the detected outlines of the T die 103 and one end face 1a of the roll, acquires the movement amount of the roll from the target position to which the roll is moved and the relative position, and outputs a movement command to the movement mechanism 40 to move the roll by the determined movement amount.

[0053] The position control method involves using the camera 10 to capture an image of the T die 103 and one end face 1a of the forming roll 1 in the axial direction, applying image processing to the target image captured by the imaging unit to detect the outlines of the T die 103 and one end face 1a of the forming roll 1, obtaining the relative position of the forming roll 1 with respect to the T die 103 from the detected outlines of the T die 103 and one end face 1a of the forming roll 1, obtaining the target position to which the forming roll 1 is to be moved and the amount of movement of the forming roll 1 from the relative position, and moving the forming roll 1 by that amount using the movement mechanism 40.

[0054] In these configurations, the relative position of the forming roll 1 with respect to the T-die 103 is acquired based on the image captured by the camera 10, and the movement amount of the forming roll 1 to the target position can be calculated based on the relative position. Then, the movement mechanism 40 is controlled to move the forming roll 1 by the calculated movement amount. This allows the forming roll 1 to be automatically positioned.

[0055] The position control device 100 further includes an illumination unit that illuminates one end surface 1a of the forming roll 1, and the illumination unit is provided in the inner region of an imaginary cylindrical surface extending from the outer peripheral surface of the roll along the central axis of the roll.

[0056] In the position control device 100, the optical axis of the illumination unit is parallel to the central axis of the forming roll 1.

[0057] In the position control device 100, the camera 10 is provided between the lighting unit and the forming roll 1 in the axial direction of the forming roll 1.

[0058] In these configurations, the outer shape of the one end face 1a of the forming roll 1 can be emphasized in the target image by irradiating the one end face 1a of the forming roll 1 with light, thereby improving the detection accuracy of the one end face 1a of the forming roll 1 in image processing of the target image.

[0059] In addition, in the position control device 100, one end surface 1a of the forming roll 1 is positioned closer to the camera 10 in the axial direction of the forming roll 1 than the T-die 103, and the T-die 103 is provided with an adjustment plate 25 having an alignment surface 25a whose position in the axial direction of the roll is the same as that of one end surface 1a of the forming roll 1.

[0060] In this configuration, even if one side surface 103a of the T die 103 and one end surface 1a of the forming roll 1 are misaligned in the axial direction of the forming roll 1, the provision of the adjusting plate 25 prevents the one end surface 1a of the forming roll 1 and the mating surface of the adjusting plate 25 from being displaced from the camera 10. The relative position of the adjusting plate 25 and the T die 103 can be known in advance. This makes it possible to prevent errors from occurring in detecting the relative position of the T die 103 and the forming roll 1 based on the outer shapes detected by image processing.

[0061] In addition, in the position control device 100, the control device 30 outputs a warning signal when the distance between the T-die 103 and the forming roll 1 becomes equal to or less than a predetermined distance threshold.

[0062] With this configuration, the worker can recognize the risk of contact between the T-die 103 and the forming roll 1, and can prevent contact between the T-die 103 and the forming roll 1 by taking measures such as emergency stopping the operation of the moving mechanism 40.

[0063] Next, a modification of this embodiment will be described.

[0064] In the above embodiment, the light 20 is positioned in the axial direction of the forming roll 1 so that the camera 10 is provided between the light 20 and one end surface 1a of the forming roll 1, and irradiates light onto one end surface 1a of the forming roll 1. In contrast, the light 20 may be provided on the opposite side of the forming roll 1 from the camera 10, and irradiate light onto the other end surface of the forming roll 1. In other words, the forming roll 1 may be positioned between the camera 10 and the light 20 in the axial direction of the forming roll 1. In this case, the light from the light 20 is not irradiated onto one end surface 1a of the forming roll 1, and therefore the brightness of the one end surface 1a is reduced in the target image. As a result, the contour of the one end surface 1a of the forming roll 1 is emphasized by the target image, and similarly to the above embodiment, the detection accuracy of the forming roll 1 from the target image can be improved.

[0065] Furthermore, in the above embodiment, the light 20 is provided inside an imaginary cylindrical surface formed by extending the cylindrical outer peripheral surface of the forming roll 1 in the axial direction, and its optical axis is parallel to the central axis of the forming roll 1. On the other hand, when irradiating one end surface 1a of the forming roll 1 with light, the arrangement of the light 20 is not limited to the configuration of the above embodiment. For example, the light 20 may be configured so that its optical axis is not parallel to the central axis of the forming roll 1 but is inclined with respect to the vertical direction so as to extend toward the forming roll 1 (i.e., the optical axis does not extend vertically).

[0066] In the above embodiment, the light 20 constantly illuminates the forming roll 1. However, for example, the light 20 may be configured to be turned on when the outer shape of the forming roll 1 cannot be detected by image processing of the target image.

[0067] The image captured by the camera 10 also includes the side of the support 6a. The side of the support 6a and / or the side 103a of the T-die 103 captured by the camera 10 may be provided with alignment marks used to correct the tilt of the casting machine 104 relative to the camera 10. For example, it is difficult to perfectly synchronize the lifting and lowering of multiple jacks 46, resulting in a misalignment between their movements, which can cause the casting machine 104 to tilt relative to the camera 10. In such cases, the target image can be corrected to eliminate the tilt of the casting machine 104 based on the alignment marks included in the target image captured by the camera 10 and normal (non-tilted) alignment marks previously stored in the control device 30. The alignment marks can be of any shape as long as they can correct the target image to eliminate the tilt of the casting machine 104, and can be located anywhere within the range included in the target image.

[0068] In the above embodiment, the adjustment unit is the adjustment plate 25 having an L-shaped cross section. However, the adjustment unit is not limited to the above embodiment and can have any shape, such as a rod-shaped member, as long as it has a positioning surface 25a that is flush with one end surface 1a of the forming roll 1. Furthermore, the side surface 103a of the T-die 103 and the positioning surface 25a of the adjustment plate 25 may be configured to have different colors so that the control device 30 can more clearly distinguish between them. For example, if the side surface 103a of the T-die 103 is a color that is relatively close to black, painting the positioning surface 25a of the adjustment plate 25 white will more reliably detect the positioning surface 25a of the adjustment plate 25 in image processing.

[0069] Furthermore, the configuration of the light 20 and the adjusting plate 25 is not essential.

[0070] In the above embodiment, the outer shape of the forming roll 1 is detected by image processing, and the positional relationship between the T-die 103 and the forming roll 1 is adjusted. However, the outer shapes of the other rolls (touch roll 2, transport roll 3) may be detected, and the positional relationship between the other rolls and the T-die 103 may be adjusted.

[0071] Although the embodiments of the present invention have been described above, the above embodiments merely illustrate some of the application examples of the present invention, and it is not intended that the technical scope of the present invention be limited to the specific configurations of the above embodiments. [Explanation of symbols]

[0072] 100 Position control device 1 Forming roll (roll) 1a One end face 2 Touch Roll (Roll) 2a One end face 3 Transport roll (roll) 10 Camera (imaging unit) 20 Light (lighting section) 25 Adjustment plate (adjustment part) 25a Alignment surface 30 Control device 40 Moving mechanism 103 T-die 104 Casting machine

Claims

1. A position control device that controls the position of a cylindrical roll that conveys a sheet discharged from a T-die, an imaging unit that images the T-die and one end surface of the roll in the axial direction; a control device that acquires the target image captured by the imaging unit; a moving mechanism for moving the roll; an illumination unit that illuminates the one end surface of the roll, The control device image processing is performed on the target image to detect the outer shapes of the T-die and the one end surface of the roll; acquiring a relative position of the roll with respect to the T-die from the detected outlines of the T-die and the one end surface of the roll; obtaining a movement amount of the roll from a target position to which the roll is to be moved and the relative position; outputting a movement command to the movement mechanism to move the roll by the movement amount; The illumination unit is provided in an inner region of a virtual cylindrical surface obtained by extending the outer circumferential surface of the roll along the central axis of the roll. Position control device.

2. 2. The position control device according to claim 1, The optical axis of the illumination unit is parallel to the central axis of the roll. Position control device.

3. 3. The position control device according to claim 1 or 2, The imaging unit is provided between the illumination unit and the roll in the axial direction of the roll. Position control device.

4. 4. A position control device according to claim 1, the one end surface of the roll is located at a position closer to the imaging unit than the T-die in the axial direction of the roll, The T-die is provided with an adjustment unit having a positioning surface that aligns the axial position of the roll with the one end surface of the roll. Position control device.

5. 5. A position control device according to claim 1, The control device a warning signal is output when the distance between the T-die and the roll becomes equal to or less than a predetermined distance threshold; Position control device.

6. A position control device that controls the position of a cylindrical roll that conveys a sheet discharged from a T-die, an imaging unit that images the T-die and one end surface of the roll in the axial direction; a control device that acquires the target image captured by the imaging unit; a moving mechanism for moving the roll, The control device image processing is performed on the target image to detect the outer shapes of the T-die and the one end surface of the roll; acquiring a relative position of the roll with respect to the T-die from the detected outlines of the T-die and the one end surface of the roll; obtaining a movement amount of the roll from a target position to which the roll is to be moved and the relative position; outputting a movement command to the movement mechanism to move the roll by the movement amount; the one end surface of the roll is located at a position closer to the imaging unit than the T-die in the axial direction of the roll, The T-die is provided with an adjustment unit having a positioning surface that aligns the axial position of the roll with the one end surface of the roll. Position control device.

7. A position control method for controlling the position of a cylindrical roll that conveys a sheet discharged from a T-die, comprising: an illumination unit provided in an inner region of an imaginary cylindrical surface obtained by extending the outer peripheral surface of the roll along the central axis of the roll illuminates one end surface of the roll in the axial direction; An imaging unit captures images of the T-die and the one end surface of the roll, image processing is performed on the target image captured by the imaging unit to detect the outer shapes of the T-die and the one end surface of the roll; acquiring a relative position of the roll with respect to the T-die from the detected outlines of the T-die and the one end surface of the roll; obtaining a movement amount of the roll from a target position to which the roll is to be moved and the relative position; moving the roll by the movement amount using a movement mechanism; Position control method.

Images