JP6268779B2 - Air turn bar - Google Patents

Description

  The present invention relates to an air turn bar that conveys a web.

  In recent years, as glass has become thinner, it has become possible to use a web transport technology such as a film for transporting glass. In a web conveyance device that performs web conveyance, for example, a web such as glass wound around a roller is unwound from the roller, and various processes are performed on the web in the process of being wound around another roller ( Roll-to-roll method).

  The turn bar used in the web transport device has, for example, an outer peripheral surface formed to include a curved surface. When the web is wound around the outer peripheral surface of the turn bar, the web transport direction changes along the outer peripheral surface. An air turn bar, which is a kind of such a turn bar and has an air hole formed on the outer peripheral surface thereof, is formed by the air pressure between the web and the air turn bar outer peripheral surface. An outer peripheral surface and a web are maintained in a non-contact state (for example, patent document 1).

JP 2009-242021 A

  By the way, in the configuration in which the web is floated by the air ejected from the ejection holes as in Patent Document 1 described above, a negative pressure region is locally formed between the outer peripheral surface of the air turn bar and the web. This is caused by the flow of air ejected from the ejection holes and the flow of air between the outer peripheral surface of the air turn bar and the web from both ends of the outer peripheral surface of the air turn bar. Therefore, there is a possibility that the web is attracted to the negative pressure region and the web contacts the outer peripheral surface of the air turn bar.

  An object of the present invention is to provide an air turn bar that can avoid web contact.

In order to solve the above-mentioned problems, another air turn bar of the present invention that supports the conveyance of the web while supporting the web with a gas pressure is provided on the outer circumferential surface including the curved surface, the outer circumferential surface, and the gas Are formed as a plurality of holes for separating the web from the outer peripheral surface, forming one part of the outer peripheral surface and a part of the injection hole closest to at least one end of the other end, on the outer peripheral surface side. headed, characterized by comprising a contact preventive portion which flow path cross-sectional area of Ru consists of inclined surfaces expanding gas, a.

In order to solve the above-mentioned problems, another air turn bar of the present invention that supports the conveyance of the web while supporting the web with a gas pressure is provided on the outer circumferential surface including the curved surface, the outer circumferential surface, and the gas Is ejected from a plurality of holes that separate the web from the outer peripheral surface, and one end of the outer peripheral surface and at least one end of the other end are located at a position separated from the end. It is formed between the starting point on a certain outer peripheral surface and the end, and is recessed inward from the portion of the outer peripheral surface that continues from the starting point in the direction away from the end, and from the end toward the starting point. And a contact preventing portion configured by an inclined surface in which the depth of the depression gradually decreases .

  According to the present invention, contact between the air turn bar and the web can be avoided.

It is explanatory drawing for demonstrating the structure of a web conveyance apparatus. It is a side view of the 3rd air turn bar. It is explanatory drawing for demonstrating the 3rd air turn bar of a comparative example. It is a figure which shows the relationship between the separation distance from an outer peripheral surface, and a pressure. It is explanatory drawing for demonstrating the structure of a contact prevention part. It is explanatory drawing for demonstrating the effect of a contact prevention part. It is explanatory drawing for demonstrating the structure of the contact prevention part in a modification.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The dimensions, materials, and other specific numerical values shown in the embodiments are merely examples for facilitating the understanding of the invention, and do not limit the present invention unless otherwise specified. In the present specification and drawings, elements having substantially the same function and configuration are denoted by the same reference numerals, and redundant description is omitted, and elements not directly related to the present invention are not illustrated. To do.

  Below, the web conveyance apparatus which conveys thin glass as a web is demonstrated. However, the web is not limited to glass and may be made of other materials such as metal and plastic.

(Web conveying device 100)
FIG. 1 is an explanatory diagram for explaining the structure of the web conveyance device 100. FIG. 1A shows a side view of the web conveyance device 100, and FIG. The top view of is shown.

Web W has one end side in the longitudinal direction is wound around the delivery roll R _1, the other longitudinal end side is wound on the winding roll R _2. When the feed roll R ₁ and the take-up roll R ₂ are rotated counterclockwise in FIG. 1A by a motor (not shown), the web W is sent out from the feed roll R _{1 and also} to the take-up roll R ₂ . It is wound up.

Web transport apparatus 100, the web W wound on the delivery rolls R ₁ is provided in the transport path of the web W to be wound around the winding roll R _2. By arranging the web conveyance device 100, the conveyance path of the web W can be changed. Although detailed explanation is omitted here, various processing processes such as surface treatment (for example, coating) and drying process on the web W are appropriately performed by arranging the web conveyance device 100 and changing the conveyance path of the web W. It becomes feasible.

  Although not shown in FIG. 1, it is possible to maintain and adjust the tension of the web W by applying a pressing force to the web W by a tension adjusting unit including a spring and an actuator. . Further, for example, a turn bar for switching the web W conveyance direction by 180 degrees from the upward direction to the downward direction in FIG. 1A may be provided, and a speed change mechanism for moving the turn bar in the vertical direction in FIG. Good. While the turn bar is moved by this speed change mechanism, the conveyance speed of the web W can be made different between upstream and downstream of the turn bar in the conveyance path of the web W.

  As shown in FIG. 1, the web conveyance device 100 includes a first air turn bar 102, a second air turn bar 104, and a third air turn bar 106 (air turn bar).

  As shown in FIG. 1B, the first air turn bar 102 and the second air turn bar 104 are wider than the width of the web W (the length in the vertical direction in FIG. 1B). Extends long in the direction.

  A plurality of ejection holes are provided on the outer peripheral surface 102a of the first air turn bar 102 and the outer peripheral surface 104a of the second air turn bar 104 shown in FIG. 1A, and these ejection holes are not shown. Air (gas) supplied from a blower or the like is ejected. The outer peripheral surfaces 102a and 104a are formed so as to face the web W, and the web W is perpendicular to the surface from the outer peripheral surfaces 102a and 104a by the pressure of air between the web W and the outer peripheral surfaces 102a and 104a. Maintained in a separate position.

By through an outer peripheral surface 102a of the first air turn bar 102, the direction to be conveyed of the web W being transported from the feed roll _{R 1} is relatively changed along the outer circumferential surface 102a, in FIG. 1 (a), The web W is conveyed toward the third air turn bar 106 from the direction of the arrow a to the direction of the arrow b. Similarly, through the outer peripheral surface 104a of the second air turn bar 104, the direction in which the web W transported from the third air turn bar 106 is transported relatively changes along the outer peripheral surface 104a, and FIG. during a), made from the direction of arrow c in the direction of arrow d, the web W is conveyed toward the winding roll R _2.

  As shown in FIG. 1A, the third air turn bar 106 is disposed on the downstream side of the first air turn bar 102 and on the upstream side of the second air turn bar 104 in the conveyance path of the web W. As shown in FIG. 1B, the third air turn bar 106 includes an outer peripheral surface 106 a that extends longer in the width direction of the web W than the width of the web W.

  FIG. 2 is a side view of the third air turn bar 106. Here, for easy understanding, the thickness of the web W and the gap between the web W and the outer peripheral surface 106a of the third air turn bar 106 are shown enlarged. As shown in FIG. 2, the outer peripheral surface 106a of the third air turn bar 106 includes a curved surface 106b. Of the outer peripheral surface 106a, flat surfaces 106c are formed at both ends of the curved surface 106b.

  The curved surface 106b is an arc having a central angle of approximately 180 degrees when viewed from the side, and the two flat surfaces 106c provided at both ends thereof are approximately parallel to each other.

  Inside the third air turn bar 106, a flow path 106d through which air is supplied by a blower (not shown) or the like is formed. Further, the outer peripheral surface 106a of the third air turn bar 106 is provided with an ejection hole 106e that communicates with the flow path 106d and includes a plurality of holes for ejecting air guided from the flow path 106d. Here, the communication path from the flow path 106d to the ejection hole 106e is not shown.

  The outer peripheral surface 106a of the third air turn bar 106 is a surface facing the web W being conveyed. The third air turn bar 106 moves the web W from the outer peripheral surface 106a to the surface by the pressure of the air ejected from the ejection holes 106e. Support in a state separated in the vertical direction.

  The web W is wound around the outer peripheral surface 106 a of the third air turn bar 106 in a state of being floated by the air pressure, and the conveyance direction of the web W is reversed by the third air turn bar 106. Thus, the 3rd air turn bar 106 assists conveyance of web W, supporting web W with the pressure of air.

  Air between the outer peripheral surface 106a of the third air turn bar 106 and the web W is lower in FIG. 2 from both ends (one end 106f and the other end 106g) of the outer peripheral surface 106a in the conveyance direction of the web W. To the side. Here, one end 106f of the outer peripheral surface 106a is an end portion on the carry-in side of the web W in the outer peripheral surface 106a, and the other end 106g of the outer peripheral surface 106a is on the carry-out side of the web W in the outer peripheral surface 106a. It is an end.

  FIG. 3 is an explanatory view for explaining a third air turn bar 1 of a comparative example. FIG. 3 (a) shows a side view of the third air turn bar 1, and FIG. The figure which shows the pressure distribution of the dashed-dotted line part of 3 (a) is shown. In FIG. 3B, the one-dot chain line portion of FIG. 3A is rotated 90 degrees clockwise. In FIG. 3B, the solid arrow indicates the direction of air flow, and the length of the arrow indicates the magnitude of the flow velocity. Further, in FIG. 3B, the density between the outer peripheral surface 1a of the third air turn bar 1 of the comparative example and the web W indicates the air pressure distribution. The higher the density, the higher the pressure and the lower the density. It indicates that the pressure is low.

  As shown in FIG. 3B, the air between the outer peripheral surface 1a of the third air turn bar 1 and the web W flows toward the one end 1f of the outer peripheral surface 1a on the side close to the web W. (A region e indicated by a broken line in FIG. 3B). Further, from the ejection hole 1e, in the direction inclined to the right side (the center side in the conveyance direction of the web W of the outer peripheral surface 1a) in FIG. 3 (b) rather than the direction perpendicular to the outer peripheral surface 1a, Air is blowing out.

  As a result, due to the Venturi effect, a backflow occurs from the one end 1f of the outer peripheral surface 1a toward the right side on the side close to the outer peripheral surface 1a (region f indicated by a broken line in FIG. 3B). Since the flow directions of the region e and the region f are opposite, a vortex (region g indicated by a broken line in FIG. 3B) is formed between the region e and the region f. Due to the vortex and the reverse flow of the region f, a negative pressure region is generated around the vortex.

  FIG. 4 is a diagram showing the relationship between the separation distance from the outer peripheral surface 1a and the pressure, and the horizontal axis indicates the distance x from the one end 1f of the outer peripheral surface 1a of the third air turn bar 1 toward the right side in FIG. The vertical axis represents pressure. Moreover, in FIG. 4, when the separation distance separated from the outer peripheral surface 1a toward the web W is a distance z, z = 0 mm, z = 1 mm, z = 2 mm, z = 3 mm, z = 4 mm, z = 5 mm. Here is a legend for each case. The starting points and directions of the distance x and the distance z are shown in FIG.

  As shown in FIG. 4, in any legend, the pressure becomes negative in the vicinity of x = 0.04 mm. This is because the negative pressure region described above is formed. In particular, when z = 0 mm, z = 1 mm, and z = 2 mm, the absolute value of the negative pressure is large.

  On the other hand, as the separation distance increases, the absolute value of negative pressure is less likely to increase even in the vicinity of x = 0.04 mm. When z = 5 mm, the absolute value of negative pressure is about half that of z = 2 mm. ing.

  That is, the larger the separation distance from the outer peripheral surface 106a of the third air turn bar 106, the farther away from the negative pressure region, the less affected by the negative pressure. Therefore, a contact prevention unit 108 is provided on the outer peripheral surface 106a of the third air turn bar 106 in order to increase the separation distance from the negative pressure region (see FIG. 2).

  The contact preventing portion 108 is provided on both the one end 106f side and the other end 106g side of the outer peripheral surface 106a. Since all the contact prevention parts 108 have substantially the same configuration, here, the contact prevention part 108 provided on the one end 106f side of the outer peripheral face 106a will be described, and provided on the other end 106g side of the outer peripheral face 106a. The description of the contact prevention unit 108 is omitted.

  FIG. 5 is an explanatory diagram for explaining the configuration of the contact prevention unit 108, and shows the one-dot chain line portion of FIG. 2 that is rotated 90 degrees clockwise. As shown in FIG. 5, the contact prevention part 108 is a hollow formed between the one end 106f of the outer peripheral surface 106a and the ejection hole 106e closest to the one end 106f. The contact preventing portion 108 is recessed on the inner side (lower side in FIG. 5) of the outer peripheral surface 106a from a portion 106h continuing from the ejection hole 106e in a direction away from the one end 106f.

  Further, the contact preventing portion 108 is formed to be recessed from the one end 106f to the ejection hole 106e closest to the one end 106f, and is a part of the outer peripheral surface 106a of the third air turn bar 106. Moreover, the contact prevention part 108 is extended over the width direction (up-down direction in FIG.1 (b)) of the outer peripheral surface 106a.

  The web W is a portion facing the contact prevention unit 108, and a separation distance (distance z shown in FIG. 5) from the outer peripheral surface 106a is increased. Therefore, it is possible to suppress the influence of the negative pressure region on the web W.

  As described above, a negative pressure region is formed between the web W and the outer peripheral surface 106a by the flow of gas ejected from the ejection holes. For example, when the length L of the contact prevention unit 108 parallel to the conveyance direction of the web W is long, the length parallel to the conveyance direction of the web W in the negative pressure region (hereinafter referred to as negative pressure length) is the contact prevention unit. It is formed shorter than the length L of 108. On the other hand, when the length L of the contact preventing portion 108 is configured to be short, the negative pressure region protrudes from one end 106f of the outer peripheral surface 106a and protrudes in the left direction (the direction away from the ejection hole 106e) in FIG. As a result, the negative pressure length of the negative pressure region is longer than the length L of the contact prevention unit 108. In this embodiment, like the latter, the length L of the contact prevention part 108 is comprised short (The length L of the contact prevention part 108 is comprised shorter than the negative pressure length of a negative pressure area | region). For this reason, the negative pressure length in the negative pressure region can be kept short. Therefore, the pressure receiving area that the web W receives from the negative pressure region is reduced, and the influence of the negative pressure region on the web W can be suppressed.

  FIG. 6 is an explanatory diagram for explaining the effect of the contact prevention unit 108. FIG. 6A illustrates the action of the third air turn bar 106 of the present embodiment on the surface of the web W on the outer peripheral surface 106a side. FIG. 6B shows the distribution of pressure acting on the outer peripheral surface 1a side of the web W in the third air turn bar 1 of the comparative example. In FIG. 6, the horizontal axis indicates the distance x from the outer peripheral surfaces 106a, 1a of the third air turn bar 106, 1 to the right side in FIG. 3B from the one end 106f, 1f, and the vertical axis indicates the pressure. Show.

  As shown in FIG. 6B, negative pressure acts on the web W in the comparative example. On the other hand, in this embodiment, a negative pressure does not act on the web W as shown in FIG. Thus, by providing the contact prevention part 108, it becomes difficult for a negative pressure to act on the web W, the web W and the outer peripheral surface 106a do not contact, and it becomes possible to avoid the damage of the web W.

  Further, since the contact preventing portion 108 extends from the one end 106f to the ejection hole 106e closest to the one end 106f, contact with the web W is avoided at any part on the one end 106f side from the ejection hole 106e. It becomes possible to do.

  FIG. 7 is an explanatory diagram for explaining the configuration of the contact prevention units 208 and 308 in the modified example. Similarly to the contact prevention unit 108, the contact prevention units 208 and 308 are provided on both the one end 106f side and the other end 106g side of the outer peripheral surface 106a, and the contact provided on the other end 106g side of the outer peripheral surface 106a. The description of the prevention units 208 and 308 is omitted.

  As shown in FIG. 7A, the contact preventing portion 208 of the first modification is a part of the ejection hole 106e closest to the one end 106f of the outer peripheral surface 106a. And the one end 208a of the contact prevention part 208 is opening of this ejection hole 106e.

  The contact prevention part 208 is comprised by the inclined surface where the flow-path cross-sectional area of air expands toward the outer peripheral surface 106a side. Here, as shown in FIG. 7A, the case where the contact prevention unit 208 is shown as a straight line when viewed from the side surface has been described, but the contact prevention unit 208 is a curved surface as shown by a curve. It may be configured.

  By providing the contact prevention part 208, the blowing speed of the air from the ejection hole 106e falls. The magnitude of the absolute value of the negative pressure in the negative pressure region is proportional to the square of the air blowing speed. By reducing the air blowing speed by the contact prevention unit 208, the negative pressure is applied to the web W. Is less likely to act, and contact between the web W and the outer peripheral surface 106a and damage to the web W can be avoided.

  Moreover, as shown in FIG.7 (b), the contact prevention part 308 of a 2nd modification is an inclined surface formed in the outer peripheral surface 106a. The contact preventing portion 308 has a shape in which the depth of the recess gradually decreases from the one end 106f of the outer peripheral surface 106a toward the ejection hole 106e closest to the one end 106f. Here, the case where the contact prevention unit 308 is indicated by a straight line when viewed from the side surface has been described, but the contact prevention unit 308 may be configured by a curved surface as indicated by a curve.

  In the comparative example described above, as shown in the region e in FIG. 3B, when the flow velocity of the air flowing out from the one end 1f side of the outer peripheral surface 1a is too high, the air flowing out to the left side from the one end 1f A sudden spread of vortex may form a vortex. If a vortex is formed, the web W may vibrate under the influence of the vortex and may come into contact with the outer peripheral surface 1a.

  Thus, as in the second modification, by providing the contact prevention unit 308, the flow velocity of the air flowing out from the one end 106f side of the outer peripheral surface 106a is suppressed, and it is difficult to form a vortex. Therefore, vibration of the web W is suppressed, and contact between the web W and the outer peripheral surface 106a and damage to the web W can be avoided.

  Further, as shown in FIG. 7C, the contact preventing portion 408 of the third modified example is an inclined surface formed on the outer peripheral surface 106a and has one end 106f than the contact preventing unit 308 of the second modified example. It extends to the position away from. The contact preventing portion 408 is formed between the starting point 408i on the outer peripheral surface 106a located at a position farther from the one end 106f and the one end 106f than the ejection hole 106e closest to the one end 106f.

  Then, the contact preventing portion 408 is recessed inwardly from a portion 406h continuous from the starting point 408i in the direction away from the one end 106f in the outer peripheral surface 106a, and the depth of the depression is increased from the one end 106f toward the starting point 408i. Decrease gradually.

  The contact prevention unit 408 of the third modified example, like the contact prevention unit 308 of the second modified example, suppresses the flow velocity of the air flowing out from the one end 106f side of the outer peripheral surface 106a and makes it difficult to form a vortex. It is possible to avoid contact between the outer peripheral surface 106a and the web W.

  In any of the above-described embodiments and modifications, the contact between the web W and the outer peripheral surface 106a can be avoided only by processing the outer peripheral surface 106a of the third air turn bar 106. Therefore, the cost can be reduced compared to the case where another device is provided to avoid contact between the web W and the outer peripheral surface 106a.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to this embodiment. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Is done.

  In the embodiment and the modification described above, the case where the outer peripheral surface 106a of the third air turn bar 106 includes the flat surface 106c has been described, but the outer peripheral surface 106a has any shape as long as the curved surface 106b is included. It may be. Further, the curved surface 106b is not limited to an arc having a central angle of approximately 180 degrees when viewed from the side, and the central angle may be different or may not be an arc.

  In the above-described embodiment and modification, the case where the gas ejected from the first air turn bar 102, the second air turn bar 104, and the third air turn bar 106 is air has been described. Also good.

  In the embodiment and the modification described above, the case where the contact prevention portions 108, 208, 308, and 408 are provided on both the one end 106f side and the other end 106g side of the outer peripheral surface 106a has been described. However, the contact preventing portions 108, 208, 308, and 408 may be provided only on either the one end 106f side or the other end 106g side of the outer peripheral surface 106a.

  The present invention can be used for an air turn bar for conveying a web.

W Web 106 3rd Air Turn Bar (Air Turn Bar)
106a Outer peripheral surface 106b Curved surface 106e Ejection hole 106f One end 106g The other end 108, 208, 308, 408 Contact prevention part 408i Starting point

Claims (2)

An air turn bar for supporting the web while supporting the web with gas pressure,
An outer peripheral surface formed including a curved surface;
An ejection hole comprising a plurality of holes provided on the outer circumferential surface and separating the web from the outer circumferential surface by gas ejection;
One end of the outer peripheral surface and a part of the ejection hole closest to at least one end of the other end, and configured by an inclined surface in which the cross-sectional area of the gas channel increases toward the outer peripheral surface side A contact prevention unit,
An air turn bar comprising: An air turn bar for supporting the web while supporting the web with gas pressure,
An outer peripheral surface formed including a curved surface;
An ejection hole comprising a plurality of holes provided on the outer circumferential surface and separating the web from the outer circumferential surface by gas ejection;
It is formed between the starting point on the outer peripheral surface at a position farther from one end of the outer peripheral surface and at least one end of the other end, and the end portion on the outer peripheral surface at a position separated from the end. In addition, the outer peripheral surface is configured by an inclined surface that is recessed inward from a portion continuous from the starting point in a direction away from the end portion, and that the depth of the recess gradually decreases from the end portion toward the starting point. A contact prevention unit,
An air turn bar comprising: