Control device, control method, program, measurement method, and molding system,

Abstract

To accurately control a magnitude of negative pressure generated near a surface of a guide plate that guides cooling air for cooling a thin-film resin in inflation molding.SOLUTION: In a control part 21 of a control device 2, an information acquisition part 201 acquires measurement results of negative pressure generated on an opposing surface facing a thin-film resin among surfaces of a cylindrical guide plate that guides cooling air that cools and solidifies the thin-film resin formed by an expansion of the air fed inside a cylindrically extruded molten resin, and a display control part 203 controls a display of the acquired measurement results.SELECTED DRAWING: Figure 3

Description

Technical Field

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[0001] The present invention relates to a control device, a control method, a program, a measurement method, and a molding system.

Background Art

[0002] In so-called inflation molding in which a resin film is formed by cooling and solidifying a thin film resin formed by the expansion of air fed into the inside of a molten resin extruded in a cylindrical shape, a cylindrical plate (hereinafter referred to as an "induction plate") that guides cooling air for cooling the thin film resin is used. The thin film resin is attracted by the negative pressure generated near the surface of the induction plate, and the shape of the thin film resin is stabilized by keeping the distance between the induction plate and the thin film resin constant. At this time, by adjusting the height of the induction plate and the wind speed of the cooling air, the magnitude of the negative pressure generated near the surface of the induction plate is adjusted.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] As described above, by adjusting the height of the induction plate and the wind speed of the cooling air, the magnitude of the negative pressure generated near the surface of the induction plate can be adjusted. However, there is no guideline for adjusting the height of the induction plate and the wind speed of the cooling air, and the situation has been such that it has been necessary to rely on the experience and intuition of the operator. On the other hand, the measurement result of the magnitude of the negative pressure generated near the surface of the induction plate can be a guideline for adjusting the height of the induction plate and the wind speed of the cooling air. However, when measuring the magnitude of the negative pressure, the presence of the hose installed for negative pressure measurement disturbs the flow of the cooling air, and the dynamic pressure rather than the static pressure of the cooling air that should originally be measured is measured. Therefore, the magnitude of the negative pressure generated near the surface of the induction plate could not be accurately measured. The objective of the present invention is to enable precise control of the magnitude of the negative pressure generated near the surface of a guide plate that guides cooling air for cooling a thin film resin in inflation molding. [Means for solving the problem]

[0005] The present invention, completed with this objective in mind, is a control device characterized by having a measurement result acquisition means for acquiring the measurement result of negative pressure generated on the surface of a cylindrical guide plate that faces the thin film resin, on the surface of the cylindrical guide plate that guides cooling air to cool and solidify a thin film resin formed by the expansion of air sent into the inside of a cylindrically extruded molten resin, and a display control means for performing control to display the acquired measurement result. The system may further include negative pressure control means that controls the magnitude of the negative pressure by adjusting at least one of the guide plate and the cooling air so that the negative pressure becomes a predetermined magnitude based on the measurement results. Furthermore, the negative pressure control means may also adjust the height of the guide plate. Furthermore, the negative pressure control means may also adjust the airflow velocity of the cooling air. Furthermore, the measurement result acquisition means may acquire the measurement result obtained by measuring the cooling air taken into a hole that connects a part of the opposing surface with a part of a surface different from the opposing surface. Furthermore, the surface different from the opposing surface may be the outer surface of the guide plate when the opposing surface is the inner surface of the guide plate. Furthermore, the hole may be either a hole that connects the upper part of the inner surface to the upper part of the outer surface, or a hole that connects the upper part of the inner surface to the lower part of the outer surface. Furthermore, the surface different from the opposing surface may be the upper surface of the guide plate. Furthermore, the measurement result acquisition means may acquire the measurement result by a negative pressure measurement unit device located at the bottom of a hole for taking in the cooling air, which is provided on a part of the opposing surface. Furthermore, the unit device may include at least a measuring means for measuring the magnitude of the negative pressure, a transmitting means for wirelessly transmitting the measurement result of the negative pressure by the measuring means to an external party, and a power storage means for storing power to enable the functions of the measuring means and the transmitting means. Furthermore, the diameter of the hole may be 2 mm or more and 3 mm or less. Furthermore, the present invention is a control method characterized by including the steps of: acquiring the measurement result of negative pressure generated on the surface of a cylindrical guide plate that guides cooling air to cool and solidify a thin film resin formed by the expansion of air sent into the inside of a cylindrically extruded molten resin, and the step of performing control to display the acquired measurement result. The process may further include the step of controlling the magnitude of the negative pressure by adjusting at least one of the guide plate and the cooling air so that the negative pressure becomes a predetermined magnitude based on the measurement results. Furthermore, the present invention is a program for a computer that provides the following functions: acquiring the measurement result of negative pressure generated on the surface of a cylindrical guide plate that guides cooling air to cool and solidify a thin film resin formed by the expansion of air sent into the inside of a cylindrically extruded molten resin, and the function of controlling the display of the acquired measurement result. Here, the computer may be further provided with a function to control the magnitude of the negative pressure by adjusting at least one of the guide plate and the cooling air so that the negative pressure becomes a predetermined magnitude based on the measurement results. Furthermore, the present invention relates to a measurement method for measuring the magnitude of negative pressure generated on the surface of a cylindrical guide plate that guides cooling air to cool and solidify a thin film resin formed by the expansion of air sent into the inside of a cylindrically extruded molten resin, the method comprising the steps of: providing a hole that connects a part of the opposing surface with a part of a surface different from the opposing surface; and taking in the cooling air through the hole to measure the magnitude of the negative pressure. Furthermore, the present invention is a molding system comprising: a measuring means for measuring the magnitude of negative pressure generated on the surface of a cylindrical guide plate that guides cooling air to cool and solidify a thin film resin formed by the expansion of air sent into the inside of a cylindrically extruded molten resin, on the surface facing the thin film resin; and a control means for controlling the magnitude of the negative pressure based on the measurement result of the measuring means, wherein the measuring means has a hose for measuring negative pressure connected to a hole on the side of the surface other than the facing surface, which connects a part of the facing surface with a part of the surface other than the facing surface. [Effects of the Invention]

[0006] According to the present invention, in inflation molding, it is possible to precisely control the magnitude of the negative pressure generated near the surface of the guide plate that guides the cooling air used to cool the thin film resin. [Brief explanation of the drawing]

[0007] [Figure 1] (A) is a cross-sectional view showing an example of a part of the configuration of an inflation molding apparatus that constitutes a molding system to which this embodiment is applied. (B) is a diagram showing an example of the overall configuration of a molding system to which this embodiment is applied. [Figure 2] This figure shows an example of the hardware configuration of the control device according to this embodiment. [Figure 3] This figure shows an example of the functional configuration of the control unit of a control device. [Figure 4] This is a flowchart showing an example of the processing flow of a control device. [Figure 5] This figure shows a specific example of a method for measuring the negative pressure generated between the guide plate and the thin film resin. [Figure 6] This figure shows a modified example of a method for measuring the negative pressure generated between the guide plate and the thin film resin. [Figure 7] This figure shows a modified example of a method for measuring the negative pressure generated between the guide plate and the thin film resin. [Figure 8] This figure shows a modified example of a method for measuring the negative pressure generated between the guide plate and the thin film resin. [Modes for carrying out the invention]

[0008] Embodiments of the present invention will be described in detail below with reference to the attached drawings. (Configuration of the inflation molding machine) Figure 1(A) is a cross-sectional view showing an example of a part of the configuration of the inflation molding apparatus 1 that constitutes the molding system to which this embodiment is applied. In the inflation molding apparatus 1, as part of the process, the extruder 30 extrudes the molten resin B (hereinafter referred to as "molten resin B"), which has been heated, toward the annular die 20, which is the nozzle, and the cylindrical molten resin B is extruded from the die 20. Then, when air W1 is sent toward the molten resin B from near the axis of the die 20, the molten resin B expands and a tubular thin film of resin F (hereinafter referred to as "thin film resin F") is formed. The thin film resin F is also called a "bubble". The thin film resin F is coaxial with the die 20. Hereinafter, the direction of the long axis of the thin film resin F may be referred to as the "axial direction". Also, the direction indicating the diameter of the die 20 may be referred to as the "radial direction".

[0009] As shown in Figure 1(A), the inflation molding apparatus 1 cools and solidifies the thin film resin F by passing cooling air W2 along the outer surface of the thin film resin F. The cooling air W2 flows from the lower side of the drawing in the axial direction (hereinafter sometimes referred to as the "first side" or simply the "lower side") to the upper side of the drawing in the axial direction (hereinafter sometimes referred to as the "second side" or simply the "upper side").

[0010] The inflation molding device 1 has guide plates 10-1 to 10-4. The guide plates 10-1 to 10-4 are cylindrical plates that guide the air W2 that becomes cooling air, and are also called "chambers". The guide plate 10-1 is arranged so as to surround the discharge port H of the molten resin B of the die 20. The guide plate 10-2 is arranged so as to surround the guide plate 10-1. The guide plate 10-3 is arranged so as to surround the guide plate 10-2. The guide plate 10-4 is arranged so as to surround the guide plate 10-3. The guide plates 10-1 to 10-4 are coaxial with the die 20 and the thin film resin F. The thickness of each of the guide plates 10-1 to 10-4 is about 5 mm (millimeters) to 10 mm (millimeters). Hereinafter, when it is not necessary to individually describe each of the guide plates 10-1 to 10-4, these are collectively referred to as "guide plate 10".

[0011] The height of each of the guide plates 10-1 to 10-4 is configured such that the guide plate 10-2 is higher than the guide plate 10-1, the guide plate 10-3 is higher than the guide plate 10-2, and the guide plate 10-4 is higher than the guide plate 10-3. Here, the "height" refers to the axial length of each of the guide plates 10-1 to 10-4. The height of each of the guide plates 10-1 to 10-4 is configured such that the ratio of increasing height gradually increases in the direction from the direction toward the radial axis (hereinafter, sometimes referred to as "inside") to the direction away from the radial axis (hereinafter, sometimes referred to as "outside") along the shape connecting the second-side ends in the axial direction of each of the guide plates 10-1 to 10-4. For example, the height of the guide plate 10-1 is about 10 cm (centimeters), the height of the guide plate 10-2 is about 20 cm (centimeters), and the height of the guide plate 10-3 is about 50 cm (centimeters). By configuring the height of each of the guide plates 10-1 to 10-4 in this way, it becomes possible to send out the thin film resin F to the second side in the axial direction along the shape connecting the second-side ends in the axial direction of each of the guide plates 10-1 to 10-4.

[0012] Among the surfaces of the guide plates 10-1 to 10-4, a negative pressure is generated by the passage of the air W2 that becomes the cooling air in the vicinity of the surface facing the thin film resin F (hereinafter referred to as the "opposing surface"). That is, the air pressure in the space between each opposing surface of the guide plates 10-1 to 10-4 and the thin film resin F is lower than the air pressure in the space on the inner surface side of the thin film resin F (a state where a negative pressure is generated). In particular, the space between the opposing surface near the second-side end in the axial direction of each of the guide plates 10-1 to 10-4 and the thin film resin F has a large negative pressure, so the thin film resin F is easily attracted to each of the guide plates 10-1 to 10-4. For example, the distance between the opposing surface near the second-side end in the axial direction of the guide plate 10-1 and the thin film resin F may approach about 5 mm (millimeters).

[0013] The inflation molding apparatus 1 stabilizes the shape of the thin film resin F by utilizing the negative pressure generated on each opposing surface of the guide plates 10-1 to 10-4. Specifically, the inflation molding apparatus 1 utilizes the large negative pressure generated in the space between the opposing surface near the second-side end in the axial direction of each of the guide plates 10-1 to 10-4 and the thin film resin F to attract the thin film resin F toward the guide plates 10-1 to 10-4. Thereby, the position and tension of the thin film resin F being fed out from the first side to the second side in the axial direction are adjusted, and the tubular shape is stabilized.

[0014] When the thin film resin F is cooled and solidified, a resin film, also called a "tube film", is formed. Although not shown in the figure, a ventilation pipe for sending the air W1 and W2 toward the molten resin B and a pump for supply and exhaust are connected. The formed resin film is sandwiched by a clamping roll device (not shown) and taken up while squeezing out the air inside the film. Thereafter, a winding device (not shown) winds up the film and cuts it to a predetermined length by a heater or a cutter. (Configuration of the molding system) FIG. 1(B) is a diagram showing an example of the overall configuration of a molding system to which the present embodiment is applied. The molding system to which this embodiment is applied is configured such that the above-described inflation molding apparatus 1 and control device 2 are connected via a network 90. ​​The network 90 is, for example, a LAN (Local Area Network), the Internet, or a wired connection.

[0015] The control device 2 controls at least some of the functions of the inflation molding apparatus 1. Specifically, the control device 2 controls the magnitude of the negative pressure so that the distance between the guide plates 10-1 to 10-4 and the thin film resin F falls within a predetermined range. The control device 2 controls the magnitude of the negative pressure by controlling the cooling air W2 and the guide plates 10-1 to 10-4. Specifically, the control device 2 controls the magnitude of the negative pressure by controlling the height of each of the guide plates 10-1 to 10-4 and by controlling the wind speed, wind direction, temperature, etc., of the cooling air W2.

[0016] The control of the height of each guide plate 10-1 to 10-4 refers to the control of adjusting the height of each guide plate 10-1 to 10-4 so that it reaches a height determined based on the magnitude of the negative pressure. The method for adjusting the height of each guide plate 10-1 to 10-4 is not particularly limited. For example, the height of each guide plate 10-1 to 10-4 may be adjusted manually or by operation (e.g., by operation via an operation panel) by an operator according to the determined height, or each guide plate 10-1 to 10-4 may move axially automatically without operator intervention.

[0017] Controlling the wind speed, direction, temperature, etc. of the cooling air W2 refers to adjusting the wind speed, direction, temperature, etc. of the air W2 so that they match the wind speed, direction, temperature, etc. determined based on the magnitude of the negative pressure. The method for adjusting the wind speed, direction, temperature, etc. of the air W2 is not particularly limited. For example, the wind speed, direction, temperature, etc. of the air W2 may be adjusted manually or by operation (e.g., by operation via a control panel) according to the determined wind speed, direction, temperature, etc., or the wind speed, direction, temperature, etc. of the air W2 may be adjusted automatically without operator intervention.

[0018] (Control device hardware configuration) Figure 2 shows an example of the hardware configuration of the control device 2 according to this embodiment. The control device 2 includes a control unit 21, a memory 22, a storage unit 23, a communication unit 24, an operation unit 25, and a display unit 26. These units are connected by a data bus, an address bus, a PCI (Peripheral Component Interconnect) bus, etc.

[0019] The control unit 21 is a processor that controls the functions of the control device 2 through the execution of various software such as the OS (operating system) and application software. The control unit 21 is composed of, for example, a CPU (Central Processing Unit). The memory 22 is a storage area that stores various software and data used for its execution, and is used as a work area during calculations. The memory 22 is composed of, for example, RAM (Random Access Memory).

[0020] The memory unit 23 is a memory area that stores input data for various software and output data from various software. The memory unit 23 is composed of, for example, an HDD (Hard Disk Drive), an SSD (Solid State Drive), or semiconductor memory used to store programs and various setting data. The memory unit 23 stores various information as a database, such as the guide plate DB121, which stores information showing the correspondence between the combination of heights of each of the guide plates 10-1 to 10-4 and the magnitude of the negative pressure generated in the space between each of the opposing surfaces of the guide plates 10-1 to 10-4 and the thin film resin F, and the cooling air DB122, which stores information showing the correspondence between the combination of wind speed, wind direction, and temperature of the cooling air W2 and the magnitude of the negative pressure generated in the space between each of the opposing surfaces of the guide plates 10-1 to 10-4 and the thin film resin F.

[0021] The communication unit 24 transmits and receives data to and from the outside via a wired or wireless network. The operation unit 25 consists of, for example, a keyboard, mouse, mechanical buttons, and switches, and accepts input operations. The operation unit 25 also includes a touch sensor that forms a touch panel integrally with the display unit 26. The display unit 26 consists of, for example, a liquid crystal display or an organic EL (Electro-Luminescence) display used for displaying information, and displays image and text data, etc.

[0022] (Functional configuration of the control unit of the control device) Figure 3 shows an example of the functional configuration of the control unit 21 of the control device 2. The control unit 21 of the control device 2 functions as an information acquisition unit 201, a negative pressure control unit 202, and a display control unit 203.

[0023] The information acquisition unit 201 acquires various types of information. For example, the information acquisition unit 201 acquires information indicating the magnitude of the negative pressure generated in the space between each of the opposing surfaces of the guide plates 10-1 to 10-4 and the thin film resin F (hereinafter referred to as "negative pressure information"). The negative pressure information may include various types of information expressed in units such as Pa (Pascals). The negative pressure information is acquired from the negative pressure measuring instrument 104 shown in Figures 5 to 7, which will be described later, and from the measurement results of the unit device 105 shown in Figure 8. The information acquisition unit 201 also acquires information regarding the air W2 as cooling air flowing in the space between each of the opposing surfaces of the guide plates 10-1 to 10-4 and the thin film resin F (hereinafter referred to as "cooling air information"). The information acquisition unit 201 also acquires information indicating the height of each of the guide plates 10-1 to 10-4 (hereinafter referred to as "guide plate information"). The cooling air information may include various types of information indicating the wind speed, wind direction, and temperature of the air W2 as cooling air.

[0024] Furthermore, the information acquisition unit 201 acquires information input by the operator via the operation unit 25. Examples of information input via the operation unit 25 include, for example, information input to specify the magnitude of the negative pressure generated in the space between each opposing surface of the guide plates 10-1 to 10-4 and the thin film resin F (hereinafter referred to as "negative pressure specification information"), information input to specify the wind speed, wind direction, and temperature of the air W2 as cooling air flowing in the space between each opposing surface of the guide plates 10-1 to 10-4 and the thin film resin F (hereinafter referred to as "cooling air specification information"), and information input to specify the height of each of the guide plates 10-1 to 10-4 (hereinafter referred to as "guide plate specification information").

[0025] The negative pressure control unit 202 controls the magnitude of the negative pressure generated in the space between the opposing surfaces of each of the guide plates 10-1 to 10-4 and the thin film resin F. Specifically, the negative pressure control unit 202 adjusts the wind speed, wind direction, temperature, etc. of the air W2, or adjusts the height of each of the guide plates 10-1 to 10-4, based on the contents of the negative pressure specification information, cooling air specification information, and guide plate specification information acquired by the information acquisition unit 201, and the information stored in the guide plate DB121 and cooling air DB122, respectively. For example, as part of the control of the air W2, wind speed control based on a predetermined wind speed is performed.

[0026] The negative pressure control unit 202 makes the above adjustments, thereby controlling the magnitude of the negative pressure generated in the space between each of the opposing surfaces of the guide plates 10-1 to 10-4 and the thin film resin F. As mentioned above, the adjustment of the air velocity, direction, temperature, etc. of the air W2, and the adjustment of the height of each of the guide plates 10-1 to 10-4 may be done manually by the operator, or it may be done automatically by instructions from the negative pressure control unit 202 to the wind velocity control device and height control device (not shown).

[0027] The display control unit 203 controls the display of various information on the display unit 26. Specifically, the display control unit 203 controls the display of information acquired by the information acquisition unit 201 on the display unit 26. Examples of information displayed on the display unit 26 by the control of the display control unit 203 include negative pressure information, cooling air information, and guide plate information. Based on the negative pressure information, cooling air information, and guide plate information displayed on the display unit 26, the operator can adjust the wind speed, wind direction, temperature, etc. of the air W2, and adjust the height of each of the guide plates 10-1 to 10-4.

[0028] (Processing flow of the control device) Figure 4 is a flowchart showing an example of the processing flow of the control device 2. Figure 4 also shows an example where the magnitude of the negative pressure, the wind speed of the cooling air W2, and the height of the guide plate 10 are specified by the operator's input. The control device 2 stores and manages information for controlling negative pressure in a database (step 401). Specifically, the control device 2 stores and manages information in the guide plate DB121 that shows the correspondence between the combination of heights of each of the guide plates 10-1 to 10-4 and the magnitude of the negative pressure generated in the space between each of the opposing surfaces of the guide plates 10-1 to 10-4 and the thin film resin F. The control device 2 also stores and manages information in the cooling air DB122 that shows the correspondence between the combination of wind speed, wind direction, temperature, etc. of the air W2 as cooling air and the magnitude of the negative pressure generated in the space between each of the opposing surfaces of the guide plates 10-1 to 10-4 and the thin film resin F.

[0029] If negative pressure is measured (YES in step 402), the control device 2 acquires negative pressure information including the measurement result (step 403) and proceeds to the process in step 404. Conversely, if negative pressure is not measured (NO in step 402), the control device 2 repeats the process in step 402 until negative pressure is measured.

[0030] When cooling air is detected (YES in step 404), the control device 2 acquires cooling air information including the measurement result (step 405) and proceeds to the process in step 406. Specifically, the control device 2 measures one or more of the following: wind speed, wind direction, and temperature of the air W2 used as cooling air. If cooling air is not detected (NO in step 404), the control device 2 repeats the process in step 404 until cooling air is detected.

[0031] When the height of guide boards 10-1 to 10-4 is measured (YES in step 406), the control device 2 acquires guide board information including the measurement result (step 407) and proceeds to the process in step 408. Conversely, if the height of guide boards 10-1 to 10-4 has not been measured (NO in step 406), the control device 2 repeats the process in step 406 until the height of guide boards 10-1 to 10-4 is measured.

[0032] The control device 2 displays the negative pressure information, cooling air information, and guide plate information acquired in steps 403, 405, and 407, respectively, on the display unit 26 (step 408). When one or more of the negative pressure specification information, cooling air specification information, and guide plate specification information are input by the operator (YES in step 409), the control device 2 acquires the input information (step 410). Conversely, if one or more of the negative pressure specification information, cooling air specification information, and guide plate specification information are not input (NO in step 409), the control device 2 repeats the process in step 409 until one or more of the negative pressure specification information, cooling air specification information, and guide plate specification information are input.

[0033] Based on the information input in step 410, the control device 2 controls the magnitude of the negative pressure generated in the space between each of the opposing surfaces of the guide plates 10-1 to 10-4 and the thin film resin F (step 411). Specifically, the control device 2 controls the magnitude of the negative pressure generated in the space between each of the opposing surfaces of the guide plates 10-1 to 10-4 and the thin film resin F by adjusting the wind speed, wind direction, temperature, etc. of the air W2, and by adjusting the height of each of the guide plates 10-1 to 10-4, according to the contents of the negative pressure specification information, cooling air specification information, and guide plate specification information acquired in step 410.

[0034] The control device 2 having the above configuration can be used not only in the mass production stage of resin films as commercial products, but also, for example, in the design stage or the condition setting (prototyping) stage of the inflation molding apparatus 1. Furthermore, it can also be provided in the form of an application program that realizes the functions of the control device 2 described above.

[0035] (Measurement of negative pressure) As described above, the control device 2 is capable of controlling the magnitude of the negative pressure so that the distance between the guide plates 10-1 to 10-4 and the thin film resin F falls within a predetermined range. The measurement of the negative pressure, which is a prerequisite for this, is performed, for example, as follows.

[0036] Figure 5 shows a specific example of a method for measuring the negative pressure generated between the guide plate 10 and the thin film resin F. Figure 5 shows a partial cross-sectional view illustrating the relationship between the guide plate 10-1 and the thin film resin F in the inflation molding apparatus 1 shown in Figure 1(A) above. As shown in Figure 5, the guide plate 10-1 is provided with a hole 101 that is radially parallel or substantially parallel, connecting the upper part of the opposing surface Ca with the upper part of the outer surface Cb when the opposing surface Ca is the inner surface. In this case, the outer surface Cb is a different surface from the opposing surface Ca.

[0037] A measuring hose 103 for a negative pressure measuring instrument 104 is connected to the outer surface Cb side of hole 101 via a joint 102. This allows air W2, which acts as a cooling breeze flowing over the upper part of the opposing surface Ca, to be drawn into hole 101. As a result, the negative pressure near the upper part of the opposing surface Ca can be measured by the negative pressure measuring instrument 104 and measuring hose 103 located on the outer surface Cb side. For example, it becomes possible to measure the negative pressure in the area A1 of the space shown by the dashed line in Figure 5 and the surrounding area.

[0038] The diameter of the hole 101 should be approximately the same as the inner diameter of the measuring hose 103, preferably about 2 mm to 3 mm in diameter. If the diameter of the hole 101 is too large, it will hinder the increase of negative pressure, and if the diameter of the hole 101 is too small, it will be difficult to guide the air W2 to the outer surface of the guide plate 10-1. The method for forming the hole 101 in the guide plate 10-1 is not particularly limited, and general methods such as machining by an electrical discharge machine or milling machine can be used. The negative pressure measuring instrument 104 and the measuring hose 103 are not particularly limited, and conventional ones can be used.

[0039] According to the negative pressure measurement method shown in Figure 5, the wind velocity in the direction normal to the opposing surface of the guide plate 10-1 is theoretically "0 (zero)," so dynamic pressure is not measured, and only static pressure can be measured. Since the negative pressure generated near the radially inner end of the guide plate 10-1 and the second axial end is the highest, it is preferable that the position of the hole 101 be close to the second axial end of the guide plate 10-1. Specifically, it is preferable that the distance from the second axial end of the guide plate 10-1 toward the first side does not exceed 2 cm (centimeters). Although guide plates 10-2 to 10-4 are not shown in Figure 5, guide plates 10-2 to 10-4 can be configured in the same way as guide plate 10-1.

[0040] (Variation 1) Figure 6 shows a modified example (modified example 1) of the method for measuring the negative pressure generated between the guide plate 10 and the thin film resin F. Figure 6 shows a partial cross-sectional view illustrating the relationship between the guide plates 10-1 and 10-2 and the thin film resin F in the inflation molding apparatus 1 shown in Figure 1(A) above. As shown in Figure 6, the guide plate 10-1 is provided with a hole 101 that connects the upper part of the opposing surface Ca and the lower part of the outer surface Cb.

[0041] The cross-sectional shape of hole 101 in Figure 6 is formed as follows, when the opposing surface Ca side is the entrance to hole 101 and the outer surface Cb side is the exit to hole 101. That is, it proceeds radially outward from the entrance on the opposing surface Ca side, and turns at a right angle or approximately right angle to the first axial side near the center of the cross-section of guide plate 10-1. Then it proceeds toward the first axial side, and turns at a right angle or approximately right angle radially outward at the lower part of guide plate 10-1. Then it proceeds radially outward and reaches the exit on the outer surface Cb side.

[0042] A measuring hose 103 for the negative pressure measuring instrument 104 is connected to the outer surface Cb side of the hole 101 via a joint 102. This allows air W2, which acts as a cooling breeze flowing over the upper part of the opposing surface Ca, to be drawn into the hole 101, similar to the example in Figure 5 described above. This enables the negative pressure near the upper part of the opposing surface Ca to be measured by the negative pressure measuring instrument 104 and measuring hose 103, which are positioned on the outer surface Cb side. For example, it becomes possible to measure the negative pressure in the area A1 of the space indicated by the dashed line in Figure 6 and the surrounding area. In this case, the outer surface Cb is a different surface from the opposing surface Ca. Furthermore, as shown in Modification 1 in Figure 6, if the hole 101 is provided at the bottom of the outer surface Cb, the negative pressure measuring instrument 104 and measuring hose 103 can be positioned at the bottom of the outer surface Cb, where they are less likely to directly affect the measurement of negative pressure.

[0043] (Modification 2) Figure 7 shows a modified example (modified example 2) of the method for measuring the negative pressure generated between the guide plate 10 and the thin film resin F. Figure 7 shows a partial cross-sectional view illustrating the relationship between the guide plates 10-1 and 10-2 and the thin film resin F in the inflation molding apparatus 1 shown in Figure 1(A) above. As shown in Figure 7, the guide plate 10-1 is provided with a hole 101 that connects the upper part of the opposing surface Ca with the upper surface Cc.

[0044] The cross-sectional shape of hole 101 in Figure 7 is formed as follows, assuming the opposite surface Ca side is the entrance to hole 101 and the upper surface Cc side is the exit to hole 101. That is, it proceeds radially outward from the entrance on the opposite surface Ca side, and turns at a right angle or approximately right angle to the second axial side near the center of the cross-section of the guide plate 10-1. Then it proceeds toward the second axial side and reaches the exit on the upper surface Cc side.

[0045] A measuring hose 103 for a negative pressure measuring instrument 104 is connected to the hole 101 on the upper surface Cc via a fitting 102. This allows air W2, which acts as a cooling breeze flowing over the upper part of the opposing surface Ca, to be drawn into the hole 101, similar to the examples in Figures 5 and 6 described above. This enables the negative pressure near the upper part of the opposing surface Ca to be measured by the negative pressure measuring instrument 104 located on the outer surface Cb and the measuring hose 103 located on the upper surface Cc. For example, it becomes possible to measure the negative pressure in the region A1 of the space indicated by the dashed line in Figure 7 and the surrounding region. In this case, the upper surface Cc is a different surface from the opposing surface Ca.

[0046] Note that, unlike the modified example 1 in Figure 6 described above, the modified example 2 in Figure 7 does not have the negative pressure measuring device 104 and the measuring hose 103 positioned at the bottom of the outer surface. The modified example 2 in Figure 7 is a method that can be adopted, for example, when there is a structural obstacle that prevents the negative pressure measuring device 104 and the measuring hose 103 from being positioned at the bottom of the guide plates 10-1 to 10-4.

[0047] (Variation 3) Figure 8 shows a modified example (modification 3) of the method for measuring the negative pressure generated between the guide plate 10 and the thin film resin F. Figure 8 shows a partial cross-sectional view illustrating the relationship between the guide plates 10-1 and 10-2 and the thin film resin F in the inflation molding apparatus 1 shown in Figure 1(A) above. As shown in Figure 8, the guide plate 10-1 has a hole 101 at the top of the opposing surface Ca for taking in cooling air W2, and a negative pressure measuring unit device 105 is positioned at the bottom of the hole 101. This allows the cooling air W2 flowing over the top of the opposing surface Ca to be taken into the hole 101, making it possible to measure the magnitude of the negative pressure near the top of the opposing surface Ca using the unit device 105 positioned at the bottom of the hole 101. For example, it becomes possible to measure the magnitude of the negative pressure in the region A1 of the space indicated by the dashed line in Figure 8 and the surrounding region.

[0048] The unit device 105 has at least the function of wirelessly transmitting the result of measuring the magnitude of the negative pressure generated in region A1, the space between the upper part of the opposing surface of the guide plate 10-1 and the thin film resin F, as negative pressure information to an external device (for example, the control device 2), and the function of storing power for measuring the magnitude of the negative pressure and power for wirelessly transmitting the measurement result of the magnitude of the negative pressure. This prevents the measuring hose 103 from being installed on the opposing surface Ca, thereby suppressing turbulence in the cooling air W2 caused by the measuring hose 103 being installed on the opposing surface Ca of the guide plate 10-1.

[0049] Modifications 1 to 3 shown in Figures 6 to 8 above each show a guide plate 10-2 arranged to surround guide plate 10-1. By making guide plate 10-2 the same configuration as guide plate 10-1, it becomes possible to measure the negative pressure generated in the space A2 between the upper part of the opposing surface of guide plate 10-2 and the thin film resin F. Guide plates 10-3 and 10-4, which are not shown, can also be made in the same configuration.

[0050] In summary, the control device, control method, program, measurement method, and molding system to which the present invention is applied only need to have the following configuration, and can take on various forms. In other words, a control device to which the present invention is applied (for example, control device 2 in Figure 1) includes a measurement result acquisition means (for example, information acquisition unit 201 in Figure 3) that acquires the measurement result of negative pressure generated on the opposing surface Ca facing the thin film resin F on the surface of a cylindrical guide plate 10 that guides a cooling air (for example, air W2 in Figure 1) that cools and solidifies a thin film resin F formed by the expansion of air W1 sent inside the cylindrically extruded molten resin B, and a display control means (for example, display control unit 203 in Figure 3) that performs control to display the acquired measurement result. This allows the operator performing the negative pressure adjustment to receive the measurement results of the negative pressure generated near the surface of the guide plate 10, which guides the cooling air used to cool the thin film resin F during inflation molding. As a result, the magnitude of the negative pressure can be precisely controlled according to the measurement results.

[0051] The system may further include a negative pressure control means (for example, the negative pressure control unit 202 in Figure 3) that controls the magnitude of the negative pressure by adjusting at least one of the guide plate 10 and the cooling air so that the negative pressure becomes a predetermined magnitude based on the negative pressure measurement results. This makes it possible to control the magnitude of the negative pressure according to the negative pressure measurement result by adjusting at least one of the guide plate 10 and the cooling air.

[0052] Furthermore, the negative pressure control means may also adjust the height of the guide plate 10. This allows control of the magnitude of the negative pressure according to the negative pressure measurement results to be achieved by adjusting the height of the guide plate 10.

[0053] Furthermore, the negative pressure control means may also adjust the airflow velocity of the cooling air. This allows for control of the magnitude of the negative pressure according to the negative pressure measurement results by adjusting the airflow velocity of the cooling air.

[0054] Alternatively, the measurement result acquisition means may acquire the measurement result by measuring the cooling air taken in through a hole 101 that connects a part of the opposing surface Ca with a part of a surface different from the opposing surface Ca (for example, the outer surface Cb in Figure 5 or the upper surface Cc in Figure 7). This prevents the measurement hose 103 of the negative pressure measuring instrument 104 from being placed on the opposing surface Ca, thereby suppressing turbulence in the cooling air caused by the measurement hose 103 being placed on the opposing surface Ca of the guide plate 10. As a result, highly accurate measurement results can be obtained with the effects of cooling air turbulence suppressed.

[0055] Furthermore, the surface different from the opposing surface Ca may be the outer surface Cb of the guide plate 10 when the opposing surface Ca is the inner surface of the guide plate 10. This allows the measurement hose 103 to be installed on the outer surface Cb of the guide plate 10, enabling the acquisition of highly accurate measurement results with reduced influence from cooling air turbulence.

[0056] Furthermore, the hole 101 may be either a hole 101 that connects the upper part of the opposing surface Ca to the upper part of the outer surface Cb, or a hole 101 that connects the upper part of the opposing surface Ca to the lower part of the outer surface Cb. This makes it possible to control the magnitude of negative pressure with high accuracy based on the measurement results of the negative pressure generated on the upper part of the opposing surface Ca of the guide plate 10, which directly affects the stability of the molding process.

[0057] Furthermore, the surface different from the opposing surface Ca may be the upper surface Cc of the guide plate 10. This allows the measurement hose 103 to be positioned on the upper surface Cc of the guide plate 10, enabling the acquisition of highly accurate measurement results with reduced influence from cooling air turbulence.

[0058] Alternatively, the means for acquiring measurement results may acquire the negative pressure measurement result from a negative pressure measurement unit device 105 located at the bottom of a hole 101 for taking in cooling air, which is provided in a part of the opposing surface Ca. This prevents the measurement hose 103 from being placed on the opposing surface Ca, thereby suppressing turbulence in the cooling air caused by the measurement hose 103 being placed on the opposing surface Ca of the guide plate 10. As a result, highly accurate measurement results can be obtained with the effects of cooling air turbulence suppressed.

[0059] Furthermore, the unit device 105 may also include at least a measuring means for measuring the magnitude of negative pressure, a transmitting means for wirelessly transmitting the negative pressure measurement result from the measuring means to an external party, and a power storage means for storing power to enable the functions of the measuring means and the transmitting means. This eliminates the need for power cables and communication cables that could disrupt the cooling airflow, thus suppressing airflow turbulence. As a result, highly accurate measurement results can be obtained with reduced impact from cooling airflow turbulence.

[0060] Furthermore, the diameter of hole 101 may be between 2 mm and 3 mm. This allows the hole diameter to be set between 2 mm and 3 mm, thereby suppressing the problem of negative pressure not increasing due to an overly large hole diameter, and suppressing the problem of air not being easily guided due to an overly small hole diameter. As a result, highly accurate measurement results can be obtained with the effects of cooling air turbulence suppressed.

[0061] Furthermore, the present invention is a control method characterized by including the steps of: acquiring the measurement result of negative pressure generated on the surface of a cylindrical guide plate that guides cooling air to cool and solidify a thin film resin formed by the expansion of air sent into the inside of a cylindrically extruded molten resin, the surface of which faces the thin film resin; and performing control to display the acquired measurement result. This allows the operator performing the negative pressure adjustment to receive the measurement results of the negative pressure generated near the surface of the guide plate 10, which guides the cooling air used to cool the thin film resin F during inflation molding. As a result, the magnitude of the negative pressure can be precisely controlled according to the measurement results.

[0062] The process may further include a step of controlling the magnitude of the negative pressure by adjusting at least one of the guide plate 10 and the cooling air so that the negative pressure becomes a predetermined magnitude based on the negative pressure measurement results. This makes it possible to control the magnitude of the negative pressure according to the negative pressure measurement results by adjusting at least one of the guide plate and the cooling air.

[0063] Furthermore, the present invention is a program for a computer that provides the following functions: acquiring the measurement result of negative pressure generated on the surface of a cylindrical guide plate that guides cooling air to cool and solidify a thin film resin formed by the expansion of air sent inside a cylindrically extruded molten resin; and controlling the display of the acquired measurement result. This allows the operator responsible for adjusting the negative pressure to receive measurement results of the negative pressure generated near the surface of the guide plate that directs the cooling air used to cool the thin film resin during inflation molding. As a result, the magnitude of the negative pressure can be controlled with high precision.

[0064] Furthermore, the present invention may also provide a function that controls the magnitude of negative pressure by adjusting at least one of the guide plate 10 and the cooling air so that the negative pressure becomes a predetermined magnitude based on the negative pressure measurement results of the computer. This makes it possible to control the magnitude of the negative pressure according to the negative pressure measurement result by adjusting at least one of the guide plate 10 and the cooling air.

[0065] Furthermore, the present invention relates to a measurement method for measuring the magnitude of negative pressure generated on a facing surface Ca of a cylindrical guide plate 10 that guides cooling air to cool and solidify a thin film resin F formed by the expansion of air W1 sent inside a cylindrically extruded molten resin B, the method comprising the steps of: providing a hole that connects a part of the facing surface Ca with a part of a surface different from the facing surface Ca; and taking cooling air into the hole 101 to measure the magnitude of negative pressure through the hole 101. This allows the negative pressure on the opposing surface Ca to be measured without installing the measurement hose 103 of the negative pressure measuring instrument 104 on the opposing surface Ca. As a result, turbulence in the cooling air caused by the measurement hose 103 being installed on the opposing surface Ca of the guide plate 10 can be suppressed. Consequently, highly accurate measurement results with the effects of cooling air turbulence suppressed can be obtained.

[0066] Furthermore, the present invention is a molding system that includes measuring means (for example, a negative pressure measuring device 104 and measuring hose 103 in Figure 5) for measuring the magnitude of negative pressure generated on the opposing surface Ca of a cylindrical guide plate 10 that guides a cooling air to cool and solidify a thin film resin F formed by the expansion of air W1 sent inside a cylindrically extruded molten resin B, and control means (for example, a control device 2 in Figure 2) for controlling the magnitude of negative pressure based on the measurement results of the measuring means, wherein the measuring means has a hose for measuring negative pressure connected to a hole (for example, hole 101 in Figure 5) on the side of the surface other than the opposing surface Ca that connects a part of the opposing surface Ca to a part of a surface other than the opposing surface Ca (for example, the outer surface Cb in Figure 5, the upper surface Cc in Figure 7). This suppresses turbulence in the cooling air caused by the placement of the negative pressure measuring hose on the surface of the guide plate 10 facing the molten resin, thereby enabling the acquisition of highly accurate negative pressure measurement results. As a result, it becomes possible to control the magnitude of the negative pressure based on highly accurate negative pressure measurement results.

[0067] (Other embodiments) Although embodiments of the present invention have been described above, the present invention is not limited to the embodiments described above. Furthermore, the effects of the present invention are not limited to those described in the embodiments described above. For example, the external configuration of a part of the inflation molding apparatus 1 shown in Figure 1(A), the configuration of the molding system shown in Figure 1(B), and the hardware configuration of the control device 2 shown in Figure 2 are all merely examples for achieving the objectives of the present invention and are not particularly limited. Similarly, the functional configuration of the control device 2 shown in Figure 3 is also merely an example and is not particularly limited. It is sufficient that the molding system in Figure 1(B) is equipped with a function that can execute the above-described process as a whole, and the functional configuration used to realize this function is not limited to the example in Figure 3.

[0068] Furthermore, the sequence of processing steps in the control device 2 shown in Figure 4 is merely illustrative and not particularly limiting. The processing does not necessarily have to be performed chronologically according to the illustrated sequence of steps; it may also be performed in parallel or individually. Similarly, the method for measuring negative pressure shown in Figures 5 to 8 is merely an example and not particularly limiting.

[0069] For example, in Figure 1(B), the inflation molding apparatus 1 and the control device 2, which constitute the molding system, are depicted as separate devices. However, the system is not limited to this. The control device 2 may function as one of the functions of the inflation molding apparatus 1.

[0070] For example, Figure 8 shows an example in which the unit device 105 is embedded in the guide plate 10-1, but it is not limited to this. As long as the opposing surface of the guide plate 10-1 is flat, the flow of air W2 as cooling air will not be disturbed, so for example, a configuration in which part or all of the unit device 105 is exposed radially outward from the outer surface Cb of the guide plate 10-1 is also acceptable.

[0071] Furthermore, although the above-described embodiment uses four layers of cylindrical guide plates 10-1 to 10-4, it is not limited to this. n layers (where n is an integer of 1 or more) of cylindrical guide plates can be arranged.

[0072] Furthermore, the shapes of the holes 101 shown in Figures 5 to 8 are merely examples and are not particularly limited. For example, the holes may be formed to extend from the entrance on the opposing surface Ca side of the guide plate 10-1 shown in Figure 6, in a gentle curve toward the radially outward and axially first side (for example, drawing a gentle "S" shape in the cross-section of the guide plate 10-1). Similarly, the shape of the holes 101 shown in Figure 7 may also be formed to extend from the entrance on the opposing surface Ca of the guide plate 10-1, in a gentle curve toward the radially outward and axially second side (for example, drawing a gentle "shi" shape in the cross-section of the guide plate 10-1). This allows the air W2 to flow smoothly through the holes 101.

[0073] Furthermore, in the above-described embodiment, a hole 101 for measuring negative pressure is provided on the opposing surface of the guide plate 10-1, but the invention is not limited to this. For example, one or more holes or irregularities for mitigating turbulence in the airflow W2 may be provided on the opposing surface of the guide plate 10-1. [Explanation of Symbols]

[0074] 1...Inflation molding apparatus, 2...Control device, 10-1 to 10-4...Guidance plate, 20...Die, 30...Extruder, 90...Network, 101...Hole, 102...Fitting, 103...Measurement hose, 104...Negative pressure measuring instrument, 105...Unit device, 201...Information acquisition unit, 202...Negative pressure control unit, 203...Display control unit, B...Molten resin, F...Thin film resin, W1, W2...Air, Ca...Opposite surface, Cb...Outer surface, Cc...Top surface

Claims

1. A measurement result acquisition means for acquiring the measurement result of negative pressure generated on the surface of a cylindrical guide plate that guides cooling air to cool and solidify a thin film resin formed by the expansion of air sent into the inside of a cylindrically extruded molten resin, the thin film resin formed by the expansion of air sent inside the cylindrical extruded molten resin, and the negative pressure generated on the surface facing the thin film resin. A display control means that performs control to display the acquired measurement results, A negative pressure control means controls the magnitude of the negative pressure by adjusting the height of the guide plate so that the negative pressure becomes a predetermined magnitude based on the measurement results, A control device characterized by having the following features.

2. The negative pressure control means is characterized by adjusting the wind speed of the cooling air. The control device according to claim 1.

3. A means for obtaining measurement results of negative pressure generated on the surface of a cylindrical guide plate that guides cooling air to cool and solidify a thin film resin formed by the expansion of air sent into the inside of a cylindrically extruded molten resin, the surface of which is opposite to the thin film resin, A display control means that performs control to display the acquired measurement results, It has, The measurement result acquisition means is characterized by acquiring the measurement result obtained by measuring the cooling air taken into a hole that connects a part of the opposing surface with a part of a surface different from the opposing surface. Control device.

4. The surface different from the aforementioned opposing surface is the outer surface of the guide plate when the opposing surface is the inner surface of the guide plate. The control device according to claim 3.

5. The hole is characterized in that it is either a hole that connects the upper part of the inner surface to the upper part of the outer surface, or a hole that connects the upper part of the inner surface to the lower part of the outer surface. The control device according to claim 4.

6. The surface different from the aforementioned opposing surface is the upper surface of the guide plate, The control device according to claim 3.

7. A means for obtaining measurement results of negative pressure generated on the surface of a cylindrical guide plate that guides cooling air to cool and solidify a thin film resin formed by the expansion of air sent into the inside of a cylindrically extruded molten resin, the surface of which is opposite to the thin film resin, A display control means that performs control to display the acquired measurement results, It has, The measurement result acquisition means is characterized by acquiring the measurement result by a negative pressure measuring unit device located at the bottom of a hole for taking in cooling air, which is provided on a part of the opposing surface. Control device.

8. The aforementioned unit device is A measuring means for measuring the magnitude of the negative pressure, A transmitting means for wirelessly transmitting the measurement result of the negative pressure by the measuring means to an external party, A power storage means for storing power necessary to enable the functions of the measuring means and the transmitting means, Characterized by having at least the following: The control device according to claim 7.

9. The hole is characterized in that its diameter is 2 mm (millimeters) or more and 3 mm (millimeters) or less. The control device according to claim 3 or 7.

10. A means for obtaining measurement results of negative pressure generated on the surface of a cylindrical guide plate that guides cooling air to cool and solidify a thin film resin formed by the expansion of air sent into the inside of a cylindrically extruded molten resin, the surface of which is opposite to the thin film resin, and A display control means that performs control to display the acquired measurement results, It has, The control device is characterized in that the measurement result acquisition means has a hole provided on the opposing surface and a measuring instrument for measuring the pressure of the air taken into the hole.

11. The steps include obtaining the measurement result of the negative pressure generated on the surface of a cylindrical guide plate that guides cooling air to cool and solidify a thin film resin formed by the expansion of air sent into the inside of a cylindrically extruded molten resin, the surface of which is opposite to the thin film resin, and The steps include: performing control to display the acquired measurement results; A control method characterized by including

12. The method further includes the step of controlling the magnitude of the negative pressure by adjusting at least one of the guide plate and the cooling air so that the negative pressure becomes a predetermined magnitude based on the measurement results. The control method according to claim 11.

13. On the computer, A function to acquire the measurement result of negative pressure generated on the surface of a cylindrical guide plate that faces the thin film resin, which is formed by the expansion of air sent into the inside of a cylindrically extruded molten resin and then cooled and solidified. A function to control the display of the acquired measurement results, Based on the measurement results, the function controls the magnitude of the negative pressure by adjusting the height of the guide plate so that the negative pressure becomes a predetermined magnitude. A program to achieve this.

14. A computer, The cylindrical guide plate, which guides cooling air to cool and solidify a thin film resin formed by the expansion of air sent inside a cylindrically extruded molten resin, has a function to acquire the measurement result of the negative pressure generated on the surface facing the thin film resin, by measuring the cooling air taken in through a hole that connects a part of the facing surface with a part of a different surface, and the function to acquire the measurement result obtained by measuring the cooling air. A function to control the display of the acquired measurement results, A program to achieve this.

15. A computer, The cylindrical guide plate guides cooling air to cool and solidify a thin film resin formed by the expansion of air sent inside a cylindrically extruded molten resin. The system includes a function to acquire the measurement result of the negative pressure generated on the surface facing the thin film resin, using a negative pressure measurement unit located at the bottom of a hole for taking in the cooling air, which is provided on a part of the facing surface. A function to control the display of the acquired measurement results, A program to achieve this.

16. A computer, The cylindrical guide plate, which guides cooling air to cool and solidify a thin film resin formed by the expansion of air sent inside a cylindrically extruded molten resin, has a function to acquire the measurement result of the negative pressure generated on the surface facing the thin film resin, which includes a hole provided on the facing surface and a function to acquire the measurement result by measuring the pressure of the air taken into the hole, A function to control the display of the acquired measurement results, A program to achieve this.

17. A measurement method for measuring the magnitude of negative pressure generated on the surface of a cylindrical guide plate that guides cooling air to cool and solidify a thin film resin formed by the expansion of air sent into the inside of a cylindrically extruded molten resin, the surface of which is opposite to the thin film resin, The step of providing a hole that connects a part of the opposing surface with a part of a surface different from the opposing surface, The steps include: measuring the magnitude of the negative pressure through the hole by introducing the cooling air into the hole; A measurement method characterized by including

18. A measuring means for measuring the magnitude of negative pressure generated on the surface of a cylindrical guide plate that guides cooling air to cool and solidify a thin film resin formed by the expansion of air sent inside a cylindrically extruded molten resin, the thin film resin formed by the expansion of air sent inside the molten resin, and the surface of the guide plate that faces the thin film resin, A control means that controls the magnitude of the negative pressure based on the measurement results of the measurement means, Includes, The molding system is characterized in that the measuring means has a hose for measuring negative pressure connected to the side of a hole that connects a part of the opposing surface with a part of a different surface, the side of the hole that connects the opposing surface with the part of the other surface.

Images