Transportation roller and roller unit

Abstract

To provide a transportation roller preventing a web from floating up from the transportation roller without providing a suction drive unit.SOLUTION: A transportation roller of the embodiment comprises a small diameter section and a large diameter section, and in the small diameter section, a first hole is formed from an outer circumference surface toward an inner circumference side. The large diameter section is offset from the small diameter section in an axial direction along a rotation axis, and has a larger outer diameter than the small diameter section. In the large diameter section, a second hole is formed from the outer circumference surface toward the inner circumference side. A connecting cavity is formed from the inside of the small diameter section to the inside of the large diameter section, connecting the first hole and the second hole. The connecting cavity is blocked to the outside in areas except for the first hole and the second hole.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] FIELD An embodiment of the present invention relates to a transport roller and a roller unit. [Background technology]

[0002] A conveying line for a sheet-like web uses a conveying roller. In the conveying line, the web is conveyed by rotating the conveying roller about a rotation axis with the web in contact with the outer peripheral surface of the conveying roller from the outer peripheral side. Here, when the web is conveyed using the conveying roller, it is required to prevent air from being entrained between the outer peripheral surface of the conveying roller and the web, and to prevent the web from lifting off the conveying roller. In addition, from the viewpoint of reducing the weight of a roller unit including the conveying roller, it is required to prevent the web from lifting off the conveying roller without providing a suction drive unit that generates a suction force inside the roller. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2007-99400 A [Patent Document 2] JP 2001-106402 A [Patent Document 3] JP 2010-47372 A [Patent Document 4] JP 2020-110848 A Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present invention is to provide a transport roller that prevents a web from lifting off the transport roller without providing a suction drive unit, and a roller unit that includes the transport roller. [Means for solving the problem]

[0005] According to an embodiment, the conveying roller includes a small diameter portion and a large diameter portion, and a first hole is formed in the small diameter portion from the outer circumferential surface toward the inner circumferential surface. The large diameter portion is offset from the small diameter portion in the axial direction along the rotation axis, and has a larger outer diameter than the small diameter portion. A second hole is formed in the large diameter portion from the outer circumferential surface toward the inner circumferential surface. The communicating cavity communicates between the first hole and the second hole, and is formed from the inside of the small diameter portion to the inside of the large diameter portion. The communicating cavity is closed to the outside in areas other than the first hole and the second hole. [Brief description of the drawings]

[0006] [Figure 1] FIG. 1 is a perspective view showing a conveying roller according to the first embodiment. [Diagram 2] FIG. 2 is a perspective view showing the conveying roller according to the first embodiment, cut along a cross section parallel or approximately parallel to the axial direction. [Diagram 3] FIG. 3 is a perspective view showing the conveying roller according to the first embodiment, cut along a cross section perpendicular or substantially perpendicular to the axial direction and passing through the small diameter portion. [Figure 4] FIG. 4 is a perspective view showing the conveying roller according to the first embodiment, cut along a cross section perpendicular or substantially perpendicular to the axial direction and passing through the large diameter portion. [Diagram 5] FIG. 5 is an enlarged perspective view of an outer shell portion of a small diameter portion in the conveying roller according to the first embodiment. [Figure 6] FIG. 6 is a perspective view showing a conveying roller according to a first modified example, taken along a cross section perpendicular or substantially perpendicular to the axial direction and passing through the large diameter portion. [Figure 7] FIG. 7 is a perspective view showing a conveying roller according to a second modified example. [Figure 8] FIG. 8 is a perspective view showing a conveying roller according to a third modified example, taken along a cross section perpendicular or substantially perpendicular to the axial direction and passing through the small diameter portion. [Figure 9] FIG. 9 is a perspective view showing a roller unit according to a fourth modified example. [Figure 10]FIG. 10 is a perspective view showing a roller unit according to a fourth modified example, taken along a cross section perpendicular or substantially perpendicular to the axial direction and passing through the small diameter portion of the conveying roller. [Figure 11] FIG. 11 is a perspective view showing a roller unit according to a fourth modified example, taken along a cross section perpendicular or substantially perpendicular to the axial direction and passing through a large diameter portion of a conveying roller. [Figure 12] FIG. 12 is a cross-sectional view showing a roller unit according to a fourth modified example, taken along a cross section parallel or approximately parallel to the axial direction. [Figure 13] FIG. 13 is a diagram showing the measurement results of pressure distribution inside and around the transport roller, measured in Example 1 of the verification related to the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] Hereinafter, embodiments will be described with reference to the drawings.

[0008] (First embodiment) First, a first embodiment will be described as an example of an embodiment. Figures 1 to 4 show a conveying roller 1 according to the first embodiment. The conveying roller 1 is used in a conveying line for a sheet-like web. Examples of webs conveyed in the conveying line using the conveying roller 1 include, but are not limited to, electrode sheets forming an electrode group of a battery and separator sheets.

[0009] 1 to 4, the conveying roller 1 is defined as having a rotation axis R as a central axis. The conveying roller 1 is defined as having an axial direction (direction indicated by arrows A1 and A2) along the rotation axis R, and a circumferential direction (direction indicated by arrows C1 and C2) around the rotation axis R. The conveying roller 1 is also defined as having a radial direction that intersects (is perpendicular or substantially perpendicular to) both the axial direction and the circumferential direction. The conveying roller 1 is defined as having a side that is closer to the rotation axis R in the radial direction, which is the inner peripheral side, and a side that is farther away from the rotation axis R in the radial direction, which is the outer peripheral side.

[0010] In the conveying line, the conveying roller 1 rotates about a rotation axis R with the web in contact with the outer peripheral surface of the conveying roller 1 from the outer peripheral side, thereby conveying the web. The conveying roller 1 is made of any of resin, rubber, metal, etc., and an example of the metal forming the conveying roller 1 is aluminum. Here, Fig. 1 is a perspective view, and Fig. 2 is a perspective view showing a state cut at a cross section parallel or approximately parallel to the axial direction. Figs. 3 and 4 are perspective views showing a state cut at a cross section perpendicular or approximately perpendicular to the axial direction.

[0011] As shown in Figs. 1 to 4, the conveying roller 1 includes a small diameter portion 2 and a large diameter portion 3 having an outer diameter larger than that of the small diameter portion 2. Fig. 3 shows a state cut in a cross section passing through the small diameter portion 2, and Fig. 4 shows a state cut in a cross section passing through the large diameter portion 3. In one example of Figs. 1 to 4, two large diameter portions 3A and 3B are provided in the conveying roller 1 as the large diameter portion 3. Each of the large diameter portions 3 is provided offset from the small diameter portion 2 in the axial direction. In one example of Figs. 1 to 4, the large diameter portion 3A is connected to the small diameter portion 2 from one side in the axial direction, and the large diameter portion 3B is connected to the small diameter portion 2 from the opposite side to the large diameter portion 3A in the axial direction. In addition, in the conveying roller 1, the large diameter portion 3A forms an end on one side in the axial direction, and the large diameter portion 3B forms an end on the opposite side to the large diameter portion 3A in the axial direction.

[0012] In the conveying roller 1, the small diameter portion 2 and the large diameter portion 3 are integrally formed, and each of the small diameter portion 2 and the large diameter portion 3 is formed in a cylindrical or approximately cylindrical shape. The conveying roller 1 is formed in a cylindrical or approximately cylindrical shape coaxial or approximately coaxial with the rotation axis R, and is rotatable in the circumferential direction around the rotation axis R as a center or approximately a center. Therefore, the small diameter portion 2 is rotatable in the axial direction around the rotation axis R integrally with the large diameter portion 3. In the example of Figs. 1 to 4, the dimension of the small diameter portion 2 along the axial direction is larger than the dimension of each of the large diameter portions 3 along the axial direction.

[0013] The conveying roller 1 is connected to a bearing (not shown) and coupled to a shaft (not shown) via the bearing. The conveying roller 1 is coupled to the shaft by the bearing so as to be rotatable relative to the shaft about a rotation axis R. In the example of the conveying roller 1 in FIGS. 1 to 4, at least one of the two large diameter portions 3 is connected to a bearing (rotary bearing).

[0014] The small diameter portion 2 includes an outer shell portion (first outer shell portion) 11 and an inner shell portion (first inner shell portion) 12. The outer shell portion 11 and the inner shell portion 12 are each formed from one end to the other end of the small diameter portion 2 in the axial direction. That is, in the small diameter portion 2, the outer shell portion 11 and the inner shell portion 12 are each formed from the end on the side where the large diameter portion 3A is located to the end on the side where the large diameter portion 3B is located in the axial direction.

[0015] In the small diameter portion 2, the outer shell portion 11 and the inner shell portion 12 are each formed over the entire circumference in the circumferential direction (the direction around the rotation axis R). In addition, in the small diameter portion 2, the outer shell portion 11 is disposed on the outer peripheral side of the inner shell portion 12. The outer shell portion 11 covers the inner shell portion 12 from the outer peripheral side over the entire circumference in the circumferential direction. Each of the outer shell portion 11 and the inner shell portion 12 is formed in a cylindrical shape, and in the example of Figs. 1 to 4, each of the outer shell portion 11 and the inner shell portion 12 is formed in a cylindrical shape or approximately cylindrical shape that is coaxial or approximately coaxial with the rotation axis R.

[0016] When the conveying roller 1 rotates, in the small diameter portion 2, the outer shell portion 11 and the inner shell portion 12 rotate together in the direction around the rotation axis R. In addition, in the small diameter portion 2, the outer peripheral surface of the small diameter portion 2 is formed by the outer peripheral surface of the outer shell portion 11, and the inner peripheral surface of the small diameter portion 2 is formed by the inner peripheral surface of the inner shell portion 12. The outer diameter of the outer shell portion 11 becomes the outer diameter of the small diameter portion 2. In the small diameter portion 2, a space is formed between the outer shell portion 11 and the inner shell portion 12 in the radial direction. The space between the outer shell portion 11 and the inner shell portion 12 is formed from one end of the small diameter portion 2 to the other end in the axial direction.

[0017] In this embodiment, in the small diameter portion 2, the space between the outer shell portion 11 and the inner shell portion 12 is divided into a plurality of extended flow paths (first extended flow paths) 15 by a partition wall (first partition wall) 13. In the example of Figs. 1 to 4, a plurality of partition walls 13 are provided inside the small diameter portion 2, and the space between the outer shell portion 11 and the inner shell portion 12 is divided into three or more extended flow paths 15. Each of the partition walls 13 extends in the radial direction from the inner shell portion 12 to the outer shell portion 11. Therefore, the inner peripheral end of each of the partition walls 13 is connected to the inner shell portion 12, and the outer peripheral end of each of the partition walls 13 is connected to the outer shell portion 11. Also, each of the partition walls 13 is formed from one end to the other end of the small diameter portion 2 in the axial direction.

[0018] Since the partition wall 13 is configured as described above, in the small diameter portion 2, between the outer shell portion 11 and the inner shell portion 12, each of the multiple extended flow passages 15 is extended from one end to the other end of the small diameter portion 2 in the axial direction. In the small diameter portion 2, between the outer shell portion 11 and the inner shell portion 12, the multiple extended flow passages 15 are arranged side by side in the circumferential direction. In addition, each of the partition walls 13 is not formed with holes or the like that would allow the multiple extended flow passages 15 to communicate with each other. Therefore, in the small diameter portion 2, between the outer shell portion 11 and the inner shell portion 12, the multiple extended flow passages 15 are isolated from each other by the partition wall 13 and do not communicate with each other.

[0019] In the small diameter portion 2, holes (first holes) 16 are formed from the outer peripheral surface toward the inner peripheral side. In the example of Figs. 1 to 4, a plurality (a large number) of holes 16 are formed in the small diameter portion 2. Each of the plurality of holes 16 penetrates the outer shell portion 11 from the outer peripheral surface to the inner peripheral surface. Each of the plurality of extended flow paths 15 formed between the outer shell portion 11 and the inner shell portion 12 opens to the outer peripheral side at one or more corresponding ones of the plurality of holes 16. Therefore, each of the extended flow paths 15 communicates with the outside of the conveying roller 1 through one or more corresponding ones of the plurality of holes 16.

[0020] FIG. 5 shows an enlarged view of the outer shell portion 11 of the small diameter portion 2 in the conveying roller 1. As shown in FIG. 1, FIG. 2, FIG. 5, etc., in the outer shell portion 11 of the small diameter portion 2, a plurality of holes (first holes) 16 are arranged side by side in the circumferential direction (direction around the rotation axis R). In addition, in one example of FIG. 1 to FIG. 5, in the outer shell portion 11, a plurality of holes 16 are arranged side by side in the axial direction (direction along the rotation axis R). Therefore, in the outer shell portion 11, a circumferential hole row in which a plurality of holes 16 are arranged side by side in the circumferential direction, and an axial hole row in which a plurality of holes 16 are arranged side by side in the axial direction are formed. In one example of FIG. 1 to FIG. 5, a plurality of circumferential hole rows and a plurality of axial hole rows are formed in the outer shell portion 11.

[0021] In each of the multiple circumferential hole rows, multiple holes 16 are arranged around the entire circumferential circumference. Each of the multiple circumferential hole rows is composed of the same number of holes 16 as the number of extended flow passages 15. In each of the multiple circumferential hole rows, a hole 16 is provided corresponding to each of the extended flow passages 15. Therefore, in each of the multiple holes 16 in each of the multiple circumferential hole rows, a corresponding one of the extended flow passages 15 opens to the outer circumferential side.

[0022] In each of the multiple axial hole rows, multiple holes 16 are arranged from one end to the other end of the small diameter portion 2 in the axial direction. The number of axial hole rows formed in the small diameter portion 2 is the same as the number of extended flow passages 15. Therefore, one corresponding axial hole row is provided for each extended flow passage 15. In the small diameter portion 2, the multiple axial hole rows are arranged in the circumferential direction (the direction around the rotation axis R). In the example of Figures 1 to 5, the multiple axial hole rows are arranged all around the small diameter portion 2 in the circumferential direction. Each of the multiple extended flow passages 15 opens to the outer circumferential side in each of the holes 16 constituting a corresponding one of the multiple axial hole rows. Note that each of the extended flow passages 15 does not communicate with the holes 16 constituting the axial hole rows other than the corresponding one of the multiple axial hole rows.

[0023] In the small diameter portion 2, no holes or the like are formed in the inner shell portion 12 that open any of the multiple extended flow passages 15 to the inner periphery. Therefore, each of the extended flow passages 15 formed between the outer shell portion 11 and the inner shell portion 12 opens to the outer periphery at one or more corresponding ones of the multiple holes 16, but does not open to the inner periphery. Therefore, in the small diameter portion 2, each of the extended flow passages 15 is closed to the outside at the inner shell portion 12.

[0024] Also, a dimension L1 along the circumferential direction and a dimension L2 along the axial direction are defined for each of the holes (first holes) 16. In the example shown in Figs. 1 to 5, the dimension L1 along the circumferential direction of each of the holes 16 is larger than the dimension L2 along the axial direction.

[0025] Each of the large diameter portions 3 includes an outer shell portion (second outer shell portion) 21, an inner shell portion (second inner shell portion) 22, an inner wall 23, and an outer wall 25. In each of the large diameter portions 3, the outer shell portion 21, the inner shell portion 22, the inner wall 23, and the outer wall 25 are formed over the entire circumference in the circumferential direction (the direction around the rotation axis R). When the conveying roller 1 rotates, in each of the large diameter portions 3, the outer shell portion 21, the inner shell portion 22, the inner wall 23, and the outer wall 25 rotate integrally in the direction around the rotation axis R.

[0026] In each of the large diameter portions 3, the outer shell portion 21 is disposed on the outer peripheral side with respect to the inner shell portion 22. The outer shell portion 21 covers the inner shell portion 22 from the outer peripheral side over the entire circumference in the circumferential direction. Each of the outer shell portion 21 and the inner shell portion 22 is formed in a cylindrical shape, and in the example of Figs. 1 to 4, each of the outer shell portion 21 and the inner shell portion 22 is formed in a cylindrical shape or a substantially cylindrical shape that is coaxial or substantially coaxial with the rotation axis R. In each of the large diameter portions 3, the outer peripheral surface of the outer shell portion 21 forms the outer peripheral surface of the large diameter portion 3, and the inner peripheral surface of the inner shell portion 22 forms the inner peripheral surface of the large diameter portion 3. In each of the large diameter portions 3, the outer diameter of the outer shell portion 21 becomes the outer diameter of the large diameter portion 3.

[0027] In each of the large diameter portions 3, the inner wall 23 and the outer wall 25 are disposed apart from each other in the axial direction (the direction along the rotation axis R). In each of the large diameter portions 3, the outer wall 25 is located outward in the axial direction relative to the inner wall 23. In the conveying roller 1, the outer wall 25 of the large diameter portion 3A forms an end face on one side in the axial direction. In the conveying roller 1, the outer wall 25 of the large diameter portion 3B forms an end face on the opposite side to the large diameter portion 3A in the axial direction.

[0028] In each of the large diameter portions 3, one end of the inner shell portion 22 in the axial direction is connected to the inner shell portion 12 of the small diameter portion 2. In each of the large diameter portions 3, the end of the inner shell portion 22 opposite to the side connected to the inner shell portion 12 of the small diameter portion 2 is connected to the inner peripheral end of the outer wall 25. Therefore, in each of the large diameter portions 3, the inner shell portion 22 extends from the inner shell portion 12 of the small diameter portion 2 to the outer wall 25 toward the outside in the axial direction. In each of the large diameter portions 3, the inner diameter of the inner shell portion 22 is the same or approximately the same as the inner diameter of the inner shell portion 12 of the small diameter portion 2, and the outer diameter of the inner shell portion 22 is the same or approximately the same as the outer diameter of the inner shell portion 12 of the small diameter portion 2. Therefore, the inner shell portion 22 of each of the large diameter portions 3 is connected to the inner shell portion 12 of the small diameter portion 2 without forming a step or the like between the inner shell portion 22 and the inner shell portion 12 of the small diameter portion 2.

[0029] In each of the large diameter sections 3, one end of the outer shell portion 21 in the axial direction is connected to the outer peripheral end of the inner wall 23. In each of the large diameter sections 3, the end of the outer shell portion 21 opposite to the side connected to the inner wall 23 is connected to the outer peripheral end of the outer wall 25. Therefore, in each of the large diameter sections 3, the outer shell portion 21 extends from the inner wall 23 to the outer wall 25 toward the outside in the axial direction. In each of the large diameter sections 3, the inner diameter of the outer shell portion 21 is larger than the inner diameter of the outer shell portion 11 of the small diameter section 2, and the outer diameter of the outer shell portion 21 is larger than the outer diameter of the outer shell portion 11 of the small diameter section 2. Therefore, the outer shell portion 21 of each of the large diameter sections 3 is located on the outer peripheral side with respect to the outer shell portion 11 of the small diameter section 2.

[0030] In each of the large diameter portions 3, the inner peripheral end of the inner wall 23 is connected to the outer shell portion 11 of the small diameter portion 2. In one example of FIG. 1 to FIG. 4, the inner wall 23 of the large diameter portion 3A is connected to one end of the outer shell portion 11 of the small diameter portion 2 in the axial direction. Then, in the outer shell portion 11 of the small diameter portion 2, the inner wall 23 of the large diameter portion 3B is connected to the end opposite to the side to which the large diameter portion 3A is connected. In each of the large diameter portions 3, the outer peripheral end of the inner wall 23 is connected to the outer shell portion 21. Due to the above-mentioned configuration, in each of the large diameter portions 3, the inner wall 23 is provided extending along the radial direction between the outer shell portion 11 and the outer shell portion 21 of the small diameter portion 2. In each of the large diameter portions 3, the inner wall 23 forms a step that positions the outer shell portion 21 on the outer peripheral side with respect to the outer shell portion 11 of the small diameter portion 2.

[0031] In each of the large diameter portions 3, the inner peripheral end of the outer wall 25 is connected to the inner shell portion 22. In each of the large diameter portions 3, the outer peripheral end of the outer wall 25 is connected to the outer shell portion 21. Due to this configuration, in each of the large diameter portions 3, the outer wall 25 extends along the radial direction between the inner shell portion 12 and the outer shell portion 21. In each of the large diameter portions 3, a space is formed between the outer shell portion 21 and the inner shell portion 22 in the radial direction. In each of the large diameter portions 3, the space between the outer shell portion 21 and the inner shell portion 22 is formed from the inner wall 23 to the outer wall 25 in the axial direction.

[0032] In this embodiment, in each of the large diameter portions 3, the space between the outer shell portion 21 and the inner shell portion 22 is divided into a plurality of extended flow paths (second extended flow paths) 27 by an extended wall (second partition wall) 26 that serves as a partition wall. In the example of Figs. 1 to 4, a plurality of extended walls 26 are provided inside each of the large diameter portions 3, and the space between the outer shell portion 21 and the inner shell portion 22 is divided into three or more extended flow paths 27.

[0033] In each of the large diameter portions 3, the extension walls 26 extend radially from the inner shell portion 22 to the outer shell portion 21. Therefore, in each of the large diameter portions 3, the inner peripheral end of each of the extension walls 26 is connected to the inner shell portion 22, and the outer peripheral end of each of the extension walls 26 is connected to the outer shell portion 21. Therefore, in each of the large diameter portions 3, each of the extension walls 26 extends from the inner peripheral side to the outer peripheral side. In the example of FIG. 1 to FIG. 4, in a cross section perpendicular or substantially perpendicular to the axial direction, each of the extension walls 26 has a straight or substantially straight shape. Also, in each of the large diameter portions 3, each of the extension walls 26 is formed from the inner wall 23 to the outer wall 25 in the axial direction.

[0034] Since the extended walls 26 are configured as described above, in the region surrounded by the outer shell portion 21, the inner shell portion 22, the inner wall 23, and the outer wall 25 in each of the large diameter portions 3, each of the multiple extended flow passages 27 extends along the radial direction. In the region surrounded by the outer shell portion 21, the inner shell portion 22, the inner wall 23, and the outer wall 25 in each of the large diameter portions 3, the multiple extended flow passages 27 are arranged side by side in the circumferential direction. In addition, no holes or the like that communicate between the multiple extended flow passages 27 are formed in each of the extended walls 26. For this reason, in the region surrounded by the outer shell portion 21, the inner shell portion 22, the inner wall 23, and the outer wall 25 in each of the large diameter portions 3, the multiple extended flow passages 27 are isolated from each other by the extended walls 26 and do not communicate with each other.

[0035] In this embodiment, each large diameter portion 3 is provided with the same number of extension walls 26 as the partition walls 13 of the small diameter portion 2. Each large diameter portion 3 is provided with an extension wall 26 corresponding to each of the partition walls 13 of the small diameter portion 2. In each large diameter portion 3, each of the extension walls 26 is connected to a corresponding one of the partition walls 13 of the small diameter portion 2 at an end on the side connected to the inner wall 23 in the axial direction.

[0036] Due to the above-mentioned configuration, in this embodiment, the same number of extended flow passages 27 as the extended flow passages 15 of the small diameter portion 2 are formed in each of the large diameter portions 3. Then, in each of the large diameter portions 3, extended flow passages 27 are formed, one for each of the extended flow passages 15 of the small diameter portion 2. In each of the large diameter portions 3, each of the extended flow passages 27 communicates with a corresponding one of the multiple extended flow passages 15 of the small diameter portion 2. Note that in each of the large diameter portions 3, each of the extended flow passages 27 does not communicate with any of the extended flow passages 15 other than the corresponding one of the multiple extended flow passages 15.

[0037] In each of the large diameter portions 3, holes (second holes) 28 are formed from the outer circumferential surface toward the inner circumferential surface. In the example shown in Figs. 1 to 4, a plurality of holes 28 are formed in each of the large diameter portions 3. Each of the plurality of holes 28 penetrates the outer shell portion 21 from the outer circumferential surface to the inner circumferential surface. In this embodiment, the same number of holes 28 as the number of extended flow paths 27 are formed in each of the large diameter portions 3. Then, in each of the large diameter portions 3, holes 28 are formed so as to correspond one by one to each of the extended flow paths 27.

[0038] In each outer shell portion 21 of the large diameter portion 3, a plurality of holes 28 are arranged side by side in the circumferential direction. Therefore, in each outer shell portion 21 of the large diameter portion 3, a circumferential hole row in which a plurality of holes 28 are arranged side by side in the circumferential direction is formed. In the example of Figs. 1 to 4, a plurality of holes 28 are arranged along the entire circumferential direction in each outer shell portion 21 of the large diameter portion 3. However, in the example of Figs. 1 to 4, in each outer shell portion 21 of the large diameter portion 3, a configuration in which a plurality of holes 28 are arranged side by side in the axial direction, i.e., an axial hole row of a plurality of holes 28 is not formed.

[0039] In each of the large diameter portions 3, each of the multiple extended flow paths 27 formed in the area surrounded by the outer shell portion 21, the inner shell portion 22, the inner wall 23, and the outer wall 25 opens to the outer circumferential side at a corresponding one of the multiple holes 28. Therefore, in each of the large diameter portions 3, each of the extended flow paths 27 communicates with the outside of the conveying roller 1 through a corresponding one of the multiple holes 28. Note that in each of the large diameter portions 3, each of the extended flow paths 27 does not communicate with any hole 28 other than the corresponding one of the multiple holes 28.

[0040] In each of the large diameter parts 3, no holes or the like are formed in the inner shell part 22 to open any of the multiple extended flow passages 27 to the inner circumferential side. In addition, in each of the large diameter parts 3, no holes or the like are formed in the inner wall 23 and the outer wall 25 to open any of the multiple extended flow passages 27 in the axial direction. Therefore, in each of the large diameter parts 3, each of the extended flow passages 27 formed in the area surrounded by the outer shell part 21, the inner shell part 22, the inner wall 23, and the outer wall 25 opens to the outer circumferential side at a corresponding one of the multiple holes 28, but does not open to the inner circumferential side or in the axial direction. Therefore, in each of the large diameter parts 3, each of the extended flow passages 27 is closed to the outside at the inner shell part 22, the inner wall 23, and the outer wall 25.

[0041] In this embodiment, a plurality of extended flow passages 15 having the above-described configuration are formed inside the small diameter portion 2, and a plurality of extended flow passages 27 having the above-described configuration are formed inside each of the large diameter portions 3. Therefore, each of the holes (first holes) 16 formed in the outer shell portion 11 of the small diameter portion 2 communicates with a corresponding one of the holes (second holes) 28 formed in the outer shell portion 21 of the large diameter portion 3A through a corresponding one of the extended flow passages 15 inside the small diameter portion 2 and a corresponding one of the extended flow passages 27 inside the large diameter portion 3A. Each of the holes 16 formed in the outer shell portion 11 of the small diameter portion 2 communicates with a corresponding one of the holes 28 formed in the outer shell portion 21 of the large diameter portion 3B through a corresponding one of the extended flow passages 15 inside the small diameter portion 2 and a corresponding one of the extended flow passages 27 inside the large diameter portion 3B.

[0042] Due to the above-mentioned configuration, in this embodiment, a communication cavity 30 that connects the hole (first hole) 16 of the small diameter portion 2 and the hole (second hole) 28 of the large diameter portion 3 is formed from the inside of the small diameter portion 2 to the inside of each of the large diameter portions 3. In this embodiment, the communication cavity 30 is composed of the extended flow passage 15 formed inside the small diameter portion 2 and the extended flow passage 27 formed inside each of the large diameter portions 3.

[0043] The portion of the communicating cavity 30 formed inside the small diameter portion 2 is divided by a partition wall (first partition wall) 13 into a plurality of extended flow paths (first extended flow paths) 15. An extended wall (second partition wall) 26 is provided in each of the portion of the communicating cavity 30 formed inside the large diameter portion 3A and the portion of the communicating cavity 30 formed inside the large diameter portion 3B. The portion of the communicating cavity 30 formed inside the large diameter portion 3 is divided by the extended wall 26 into a plurality of extended flow paths (second extended flow paths) 27.

[0044] In the small diameter portion 2, each of the extended flow passages 15 opens to the outer periphery only at one or more corresponding holes 16, as described above, and does not open to the inner periphery. In the large diameter portion 3, each of the extended flow passages 27 opens to the outer periphery only at one corresponding hole 28, as described above, and does not open to the inner periphery or axial direction. Therefore, the communication cavity 30 that communicates between the hole (first hole) 16 of the small diameter portion 2 and the hole (second hole) 28 of the large diameter portion 3 opens only at the holes 16 and 28, and communicates with the outside of the conveying roller 1 only through the holes 16 and 28. Therefore, the communication cavity 30 is closed to the outside of the conveying roller 1 at the portions other than the holes 16 and 28.

[0045] When the transport roller 1 is used to transport a web, the transport roller 1 is rotated about the rotation axis R with the web in contact with the outer circumferential surface of the small diameter portion 2 from the outer circumferential side. At this time, the web does not come into contact with the outer circumferential surface of the large diameter portion 3. Also, the web comes into contact with the outer circumferential surface of the small diameter portion 2 only over a partial range in the circumferential direction, and the web does not come into contact over the entire circumferential direction. In other words, there is a portion of the outer circumferential surface of the small diameter portion 2 that does not come into contact with the transported web over a partial range in the circumferential direction.

[0046] In addition, the web being transported has a longitudinal direction, a width direction intersecting (perpendicular or approximately perpendicular) with the longitudinal direction, and a thickness direction intersecting (perpendicular or approximately perpendicular) with both the longitudinal direction and the width direction. In the web, the dimension along the longitudinal direction is larger than the dimension along the width direction, and the dimension along the width direction is larger than the dimension along the thickness direction. In the transport line, the web is transported with the longitudinal direction of the web aligned along the transport direction. In addition, the small diameter portion 2 of the transport roller 1 contacts the web being transported from one side in the thickness direction. The width direction of the web being transported coincides or approximately coincides with the axial direction of the transport roller 1. In addition, in the portion of the web that contacts the outer circumferential surface of the small diameter portion 2 of the transport roller 1, the longitudinal direction of the web is aligned with the circumferential direction of the transport roller 1.

[0047] In the conveying roller 1 of this embodiment, as described above, the small diameter portion 2 and the large diameter portion 3 are arranged so as to be shifted from each other in the axial direction, and a hole (first hole) 16 is formed in the small diameter portion 2, and a hole (second hole) 28 is formed in the large diameter portion 3. A communication cavity 30 that connects the hole 16 of the small diameter portion 2 and the hole 28 of the large diameter portion 3 is formed from the inside of the small diameter portion 2 to the inside of the large diameter portion 3, and the communication cavity 30 is closed to the outside in the areas other than the holes 16 and 28.

[0048] Due to this configuration, when the transport roller 1 is rotating during transport of the web, the centrifugal force acting on each of the large diameter portions 3 is greater than the centrifugal force acting on the small diameter portion 2. Since the centrifugal force on the large diameter portion 3 is greater than the centrifugal force on the small diameter portion 2, an air flow toward the outer periphery is generated in each of the portions of the communicating cavity 30 formed inside the large diameter portion 3. As a result, in each of the large diameter portions 3, air flows out of the transport roller 1 from each of the multiple extended flow paths 27 through a corresponding one of the holes 28.

[0049] In each of the large diameter portions 3, air flows out through each of the holes 28 to the outside, and thus in the communication cavity 30, an air flow is generated from the inside of the small diameter portion 2 to the inside of each of the large diameter portions 3. As a result, air flows from each of the extended flow paths 15 formed in the inside of the small diameter portion 2 to a corresponding one of the extended flow paths 27 formed in the inside of the large diameter portion 3A and a corresponding one of the extended flow paths 27 formed in the inside of the large diameter portion 3B. As air flows from the inside of the small diameter portion 2 to the inside of each of the large diameter portions 3 in the communication cavity 30, the portion formed in the inside of the small diameter portion 2 in the communication cavity 30 is in a negative pressure state where the air pressure is lower than that outside the conveying roller 1. As a result, an air flow is generated that flows from the outside of the conveying roller 1 into the inside of the small diameter portion 2 through each of the holes 16.

[0050] In this embodiment, as described above, when the web is being transported using the transport roller 1, air flows from the outside of the transport roller 1 into the inside of the small diameter portion 2 through each of the holes 16. Therefore, when the web is being transported, a suction force toward the inside of the small diameter portion 2 acts on the web being transported. This appropriately prevents air from being drawn in between the outer circumferential surface of the small diameter portion 2 of the transport roller 1 and the web, and appropriately prevents the web from lifting off the transport roller 1.

[0051] In this embodiment, without providing a suction drive unit, air flows from the outside of the conveying roller 1 into the inside of the small diameter portion 2 through each of the holes 16 due to the difference in centrifugal force between the large diameter portion 3 and the small diameter portion 2. Without providing a suction drive unit, the web is prevented from lifting up from the conveying roller 1.

[0052] In this embodiment, the portion of the communicating cavity 30 formed inside the small diameter portion 2 is divided into a plurality of extended flow paths 15 by the partition wall 13. Each of the plurality of extended flow paths 15 opens to the outer periphery through one or more corresponding holes 16. This configuration effectively prevents air that has flowed into the inside of the small diameter portion 2 from flowing out through the holes 16 to the outside of the small diameter portion 2 in the circumferential direction within a range where the web is not in contact with the outer periphery of the small diameter portion 2. As a result, in the communicating cavity 30, the air that has flowed into the inside of the small diameter portion 2 through the holes 16 flows appropriately toward the inside of each of the large diameter portions 3.

[0053] In this embodiment, each of the portions of the communication cavity 30 formed inside the large diameter portion 3 is divided into a plurality of extended flow passages 27 by the extended walls 26. Each of the plurality of extended flow passages 27 opens to the outer circumferential side through one or more corresponding holes 28 and communicates with a corresponding one of the plurality of extended flow passages 15 formed inside the small diameter portion 2. With this configuration, in the communication cavity 30, air flows more appropriately from the hole 16 to the hole 28 through the corresponding extended flow passage 15 and the corresponding extended flow passage 27. Therefore, in the communication cavity 30, air flows more appropriately from the hole 16 of the small diameter portion 2 to each hole 28 of the large diameter portion 3.

[0054] In this embodiment, a circumferential hole row in which multiple holes 16 are lined up in the circumferential direction is formed in the outer shell 11 of the small diameter portion 2, and multiple holes 16 are lined up all around the outer shell 11 of the small diameter portion 2 in the circumferential direction. Therefore, no matter at what angular position in the circumferential direction the transported web comes into contact with the outer circumferential surface of the small diameter portion 2, the suction force toward the inside of the small diameter portion 2 acts appropriately on the transported web. This further appropriately prevents the web from lifting up from the transport roller 1.

[0055] In this embodiment, an axial hole row in which multiple holes 16 are aligned in the axial direction is formed in the outer shell 11 of the small diameter portion 2, and multiple holes 16 are aligned from one end to the other end in the axial direction in the small diameter portion 2. Therefore, a suction force toward the inside of the small diameter portion 2 acts over the entire width or almost the entire width of the web being transported. This more appropriately prevents the web from lifting up from the transport roller 1.

[0056] In one example of this embodiment, the dimension L1 along the circumferential direction of each of the holes (first holes) 16 formed in the small diameter portion 2 is larger than the dimension L2 along the axial direction. Here, the web is transported with tension acting in the longitudinal direction. Therefore, when the dimension L2 of each of the holes 16 along the axial direction of the transport roller 1 becomes smaller, the dimension of each of the holes 16 in the direction intersecting (perpendicular or substantially perpendicular) the direction in which the tension acts on the transported web becomes smaller. Therefore, even if a suction force toward the inside of the small diameter portion 2 acts on the transported web, it becomes difficult for the transported web to be inserted into each of the holes 16. As a result, wrinkles are less likely to occur in the transported web.

[0057] In addition, by increasing the opening area of ​​each of the holes 16 on the outer peripheral surface of the small diameter portion 2, the suction force directed toward the inside of the small diameter portion 2 through each of the holes 16 increases. This improves the suction performance for the transported web. On the other hand, by decreasing the opening area of ​​each of the holes 16 on the outer peripheral surface of the small diameter portion 2, the contact area between the web and the outer peripheral surface of the small diameter portion 2 increases. This prevents a decrease in the frictional force between the transported web and the small diameter portion 2. For this reason, the opening area of ​​each of the holes 16 on the outer peripheral surface of the small diameter portion 2 is adjusted to an appropriate size in accordance with the balance between the suction performance for the transported web and the frictional force acting from the small diameter portion 2 on the web.

[0058] (Modification) In the first modification shown in FIG. 6, as in the above embodiment, the space between the outer shell portion 21 and the inner shell portion 22 in each of the large diameter portions 3 is divided into a plurality of extended flow paths (second extended flow paths) 27 by an extended wall (second partition wall) 26 that serves as a partition wall. That is, each of the portions formed inside the large diameter portion 3 in the communicating cavity 30 is divided into a plurality of extended flow paths 27 by the extended wall 26. However, in this modification, each of the extended walls 26 has an arc shape or an approximately arc shape in a cross section perpendicular or approximately perpendicular to the axial direction. Note that FIG. 6 shows the conveying roller 1 cut in a cross section perpendicular or approximately perpendicular to the axial direction and passing through the large diameter portion 3.

[0059] This modification also provides the same functions and effects as the above-described embodiment, etc. That is, this modification also prevents the web from lifting up from the transport roller 1 without providing a suction drive unit.

[0060] In this modification, the extension walls 26 are provided in the communicating cavity 30 in the portion formed inside the large diameter portion 3, and in a cross section perpendicular or substantially perpendicular to the axial direction, each of the extension walls 26 has an arc shape or a substantially arc shape. With this configuration, the conveying roller 1 rotates each of the extension walls 26 about the rotation axis R, so that the communicating cavity 30 in the portion formed inside the large diameter portion 3 is more likely to generate an air flow toward the outer periphery. That is, in each of the large diameter portions 3, an air flow toward the outside through the corresponding one of the holes 28 is more likely to be generated in each of the extended flow passages 27. As a result, in the communicating cavity 30, an air flow from the hole 16 toward the hole 28 through the corresponding extended flow passage 15 and the corresponding extended flow passage 27 is more appropriately generated.

[0061] In the above-mentioned embodiment, the outer shell 11 of the small diameter portion 2 has an axial hole row in which the holes 16 are arranged in the axial direction, but the present invention is not limited to this. In the second modified example shown in FIG. 7, the outer shell 11 of the small diameter portion 2 does not have a configuration in which the holes 16 are arranged in the axial direction, that is, an axial hole row made of the holes 16 is not formed. However, in this modified example, a circumferential hole row in which a plurality of holes (first holes) 16 are arranged in the circumferential direction is also formed in the outer shell 11 of the small diameter portion 2. In this modified example, only one circumferential hole row made of the holes 16 is formed in the outer shell 11. In the circumferential hole row, the holes 16 are arranged over the entire circumference in the circumferential direction. In FIG. 7, the entire conveying roller 1 is shown in a perspective view.

[0062] In one modified example, only one hole 16 may be provided in the outer shell 11 of the small diameter section 2. In another modified example, an axial hole row in which multiple holes 28 are aligned in the axial direction may be formed in each outer shell 21 of the large diameter section 3. In another modified example, only one hole 28 may be provided in each outer shell 21 of the large diameter section 3.

[0063] In the above-mentioned embodiment, the portion of the communicating cavity 30 disposed inside the small diameter portion 2 is divided into a plurality of extended flow paths (first extended flow paths) 15 by the partition wall (first partition wall) 13, but the present invention is not limited thereto. In the third modified example shown in FIG. 8, the partition wall 13 is not provided inside the small diameter portion 2. Then, only one extended flow path 15 is formed in the portion of the communicating cavity 30 disposed inside the small diameter portion 2, that is, in the space between the outer shell portion 11 and the inner shell portion 12 in the small diameter portion 2. In this modified example, the extended flow path 15 is also extended from one end to the other end of the small diameter portion 2 in the axial direction. In this modified example, one extended flow path 15 is formed inside the small diameter portion 2 over the entire circumference in the circumferential direction. Note that FIG. 8 shows the conveying roller 1 cut in a cross section perpendicular or substantially perpendicular to the axial direction and passing through the small diameter portion 2.

[0064] In this modification, no extended wall (second partition wall) 26 is provided inside each of the large diameter portions 3. Only one extended flow passage 27 is formed in each of the portions of the communicating cavity 30 that are disposed inside the large diameter portions 3. In this modification, one extended flow passage 27 is formed over the entire circumferential direction in each of the large diameter portions 3. In this modification, one extended flow passage 15 inside the small diameter portion 2 communicates with one extended flow passage 27 inside the large diameter portion 3 in the communicating cavity 30.

[0065] In any of the modified examples described above, one or more holes 16 are formed in the small diameter portion 2, and one or more holes 28 are formed in each of the large diameter portions 3. A communicating cavity 30 that connects the holes 16, 28 is formed from the inside of the small diameter portion 2 to the inside of each of the large diameter portions 3. The communicating cavity 30 is closed to the outside in areas other than the holes 16, 28.

[0066] With this configuration, when the conveying roller 1 is rotated, an air flow is generated in the communicating cavity 30 from the hole 16 in the small diameter portion 2 toward the hole 28 in the large diameter portion 3, similar to the previously described embodiment. As a result, similar to the previously described embodiment, the portion of the communicating cavity 30 formed inside the small diameter portion 2 is in a negative pressure state where the air pressure is lower than the air pressure outside the conveying roller 1, and an air flow is generated that flows from the outside of the conveying roller 1 into the inside of the small diameter portion 2 through the hole 16. Therefore, similar to the previously described embodiment, the web is prevented from floating up from the conveying roller 1 without providing a suction drive unit.

[0067] 9 to 12 show a roller unit 40 according to a fourth modified example. In addition to the conveying roller 1, the roller unit 40 includes a shaft 41 and a bearing 50. As with the conveying roller 1, the roller unit 40 also defines an axial direction (direction indicated by arrows A1 and A2) along the rotation axis R, a circumferential direction (direction indicated by arrows C1 and C2) around the rotation axis R, and a radial direction intersecting (perpendicular or substantially perpendicular to) both the axial direction and the circumferential direction. Also in the roller unit 40, the side approaching the rotation axis R in the radial direction is the inner circumferential side, and the side away from the rotation axis R in the radial direction is the outer circumferential side.

[0068] Here, Fig. 9 shows a perspective view of the roller unit 40 as a whole, Fig. 10 shows a perspective view of a cross section perpendicular or nearly perpendicular to the axial direction and passing through the small diameter portion 2 of the conveying roller 1, Fig. 11 shows a perspective view of a cross section perpendicular or nearly perpendicular to the axial direction and passing through the large diameter portion 3 of the conveying roller 1, and Fig. 12 shows a cross section parallel or nearly parallel to the axial direction.

[0069] As shown in FIGS. 9 to 12, in the roller unit 40, the shaft 41 supports the conveying roller 1 from the inner periphery side. The conveying roller 1 is supported by the shaft 41 so as to be rotatable about the rotation axis R. In the roller unit, the conveying roller 1 is connected to a bearing 50 and is coupled to the shaft 41 via the bearing 50. The conveying roller 1 is coupled to the shaft 41 via the bearing 50 so as to be rotatable relative to the shaft 41 around the rotation axis R. In this modification, the conveying roller 1 is coupled to the shaft 41 via the two bearings 50. In the conveying roller 1, the large diameter portion 3A is connected to one of the two bearings 50, and the large diameter portion 3B is connected to the other of the two bearings.

[0070] The shaft 41 includes a shaft body 42. The shaft body 42 extends along the axial direction of the conveying roller 1 and the roller unit 40. In this modification, the shaft body 42 is formed in a cylindrical shape or a substantially cylindrical shape that is coaxial or substantially coaxial with the rotation axis R. The shaft body 42 passes through the conveying roller 1 in the axial direction. The shaft body 42 extends along the axial direction, passing through an area on the inner periphery side of the small diameter portion 2 and the large diameter portion 3 of the conveying roller 1.

[0071] In this modification, the small diameter portion 2 of the conveying roller 1 has the same configuration as that of the first embodiment. Therefore, the space between the outer shell portion 11 and the inner shell portion 12 of the small diameter portion 2, i.e., the portion formed inside the small diameter portion 2 in the communicating cavity 30, is divided into a plurality of extended flow paths 15 by the partition wall 13. Each of the extended flow paths 15 opens to the outer periphery only at one or more corresponding holes 16, and does not open to the inner periphery. In this modification, the inner shell portion 12 of the small diameter portion 2 covers the shaft body 42 from the outer periphery over the entire circumference in the circumferential direction.

[0072] Also in this modification, each of the large diameter portions 3 of the conveying roller 1 includes an outer shell portion 21, an inner wall 23, and an outer wall 25. However, in this modification, each of the large diameter portions 3 does not include an inner shell portion 22. In this modification, two flange portions 43 are formed on the shaft body 42. Each of the flange portions 43 protrudes outwardly from the entire circumferential direction relative to the portions of the shaft body 42 other than the flange portions 43.

[0073] In this modification, one of the two flange portions 43 is disposed inside the large diameter portion 3A and abuts against the inner shell portion 12 of the small diameter portion 2 from the side where the large diameter portion 3A is located in the axial direction. The other of the two flange portions 43 is disposed inside the large diameter portion 3B and abuts against the inner shell portion 12 of the small diameter portion 2 from the side where the large diameter portion 3B is located in the axial direction. The outer diameter of each of the flange portions 43 of the shaft body 42 is the same or approximately the same as the outer diameter of the inner shell portion 12 of the small diameter portion 2. Therefore, each of the flange portions 43 of the shaft body 42 abuts against the inner shell portion 12 of the small diameter portion 2 without forming a step or the like between them.

[0074] In this modification, inside each large diameter portion 3, a space is formed in the radial direction between the flange portion 43 of the shaft body 42 and the outer shell portion 21. Inside each large diameter portion 3, the space between the outer shell portion 21 and the flange portion 43 is formed in the axial direction from the inner wall 23 to the outer wall 25. Therefore, inside each large diameter portion 3, a space is formed in an area surrounded by the outer shell portion 21, the flange portion 43, the inner wall 23, and the outer wall 25. In this modification, the space inside each large diameter portion 3 constitutes a part of the communicating cavity 30.

[0075] In this modification, inside each large diameter portion 3, in addition to the multiple extended flow passages 27, a junction space 46 is formed in the space surrounded by the outer shell portion 21, the flange portion 43, the inner wall 23, and the outer wall 25. Inside each large diameter portion 3, the junction space 46 is disposed on the inner circumferential side of the multiple extended flow passages 27. In this modification, the multiple extended flow passages 27 are also separated from each other by the extension wall 26, and each of the multiple extended flow passages 27 opens to the outer circumferential side at a corresponding one of the holes 28.

[0076] In this modification, a communication cavity 30 that connects the hole (first hole) 16 of the small diameter portion 2 and the hole (second hole) 28 of the large diameter portion 3 is also formed from the inside of the small diameter portion 2 to the inside of each of the large diameter portions 3. In this modification, the communication cavity 30 is composed of an extended flow passage 15 formed in the inside of the small diameter portion 2, and an extended flow passage 27 and a junction space 46 formed in each of the large diameter portions 3. In each of the large diameter portions 3, the multiple extended flow passages 15 from the small diameter portion 2 join in the junction space 46. Then, in each of the large diameter portions 3, the junction space 46 branches into multiple extended flow passages 27. Therefore, in the communication cavity 30, each of the multiple extended flow passages 15 communicates with the extended flow passage 27 through the junction space 46.

[0077] In this modification, a through hole 48 is formed in each of the large diameter portions 3, penetrating the outer wall 25 in the axial direction. In the roller unit 40 of this modification, a bearing 50 is disposed in each of the through holes 48 of the large diameter portion 3. In this modification, two lid portions 47 are formed on the shaft 41. Each of the two lid portions 47 protrudes toward the outer periphery from a corresponding one of the two flange portions 43 of the shaft body 42. Each of the lid portions 47 protrudes from the flange portion 43 over the entire circumference in the circumferential direction. In each of the large diameter portions 3, the through hole 48 is blocked by the lid portion 47 of the shaft 41. Therefore, in each of the large diameter portions 3, the space (extended flow path 27 and junction space portion 46) formed inside is blocked from the outside at the through hole 48, and does not communicate with the outside through the through hole 48.

[0078] In each of the large diameter portions 3, the space (extended flow passage 27 and junction space 46) formed in the region surrounded by the outer shell portion 21, the flange portion 43 of the shaft body 42, the inner wall 23, and the outer wall 25 is open to the outer periphery side in each of the multiple holes 28, but is not open to the inner periphery side or in the axial direction. Therefore, in each of the large diameter portions 3, the internal space is closed off from the outside by the flange portion 43, the inner wall 23, and the outer wall 25.

[0079] Due to the above-mentioned configuration, even in this modification, the communication cavity 30 that connects the hole (first hole) 16 of the small diameter portion 2 and the hole (second hole) 28 of the large diameter portion 3 is open only at the holes 16, 28, and communicates with the outside of the conveying roller 1 only through the holes 16, 28. Therefore, the communication cavity 30 is closed to the outside at the portions other than the holes 16, 28.

[0080] In this modification, a plurality of protruding plate portions 45 protrude from the outer circumferential surface of each of the flange portions 43 of the shaft body 42. A plurality of protruding plate portions 45 are arranged in the joining space portion 46 inside each of the large diameter portions 3. Therefore, in this modification, a protruding plate portion 45 is arranged in each of the portions of the communicating cavity 30 formed inside the large diameter portion 3. A plurality of protruding plate portions 45 are arranged in a line in the circumferential direction inside each of the large diameter portions 3. In the example of Figs. 9 to 12, a plurality of protruding plate portions 45 are arranged in a line in the circumferential direction inside each of the large diameter portions 3, i.e., in each of the joining space portions 46.

[0081] Each of the protruding plate parts 45 is disposed with its plate thickness direction aligned with the axial direction of the conveying roller 1. In one example of Figs. 9 to 12, the plate width direction of each of the protruding plate parts 45 is inclined with respect to both the axial direction and the circumferential direction of the conveying roller 1. Also, in one example of Figs. 9 to 12, each of the protruding plate parts 45 is extended parallel or approximately parallel to the radial direction of the conveying roller 1 from the outer peripheral surface (the root of the protrusion) of the flange part 43 to the protruding end. However, in one example, each of the protruding plate parts 45 may protrude from the flange part 43 in a state inclined with respect to the radial direction of the conveying roller 1. In this case, it is preferable that each of the protruding plate parts 45 is inclined so as to move away from the small diameter part 2 in the axial direction of the conveying roller 1 as it approaches the protruding end.

[0082] Furthermore, in this modified example, the multiple protruding plate portions 45 are fixed to the shaft main body 42. Therefore, even if the conveying roller 1 rotates about the rotation axis R, the protruding plate portions 45 do not rotate.

[0083] This modification also provides the same functions and effects as the above-described embodiment, etc. That is, this modification also prevents the web from lifting up from the transport roller 1 without providing a suction drive unit.

[0084] In this modification, the shaft 41 has a protruding plate portion 45 protruding from the shaft body 42 toward the outer periphery. The protruding plate portion 45 is disposed in a portion of the communicating cavity 30 formed inside the large diameter portion 3. With this configuration, when the conveying roller 1 rotates about the rotation axis R, a strong air flow toward the outer periphery is generated in the portion of the communicating cavity 30 formed inside the large diameter portion 3. This allows the air flow from the hole 16 toward the hole 28 in the communicating cavity 30 to be generated more appropriately.

[0085] In this modification, the through-hole 48 in each of the large diameter portions 3 is closed by the lid portion 47 of the shaft 41. This appropriately prevents air from flowing out from the inside of each of the large diameter portions 3 to the outside through the through-hole 48.

[0086] In the above embodiment, the conveying roller 1 is provided with one small diameter portion 2 and two large diameter portions 3, and the small diameter portion 2 is connected to the large diameter portion 3 from both sides in the axial direction. However, the number of small diameter portions 2 and large diameter portions 3 and the positions of the small diameter portions 2 and large diameter portions 3 in the conveying roller 1 are not limited to the numbers and arrangements in the above embodiment. In one modified example, only one small diameter portion 2 and one large diameter portion 3 are provided.

[0087] In another modified example, the conveying roller 1 is provided with one large diameter portion 3 and two small diameter portions 2, and the large diameter portion 3 is connected to the small diameter portions 2 from both sides in the axial direction. In this modified example, two webs can be conveyed using the conveying roller 1. In this case, one of the two webs is brought into contact with the outer peripheral surface of one of the two small diameter portions 2 in the conveying roller 1, and the other of the two webs is brought into contact with the outer peripheral surface of the other of the two small diameter portions 2. Therefore, as long as the conveying roller 1 has one or more small diameter portions 2 and one or more large diameter portions 3, and the large diameter portion 3 is arranged offset in the axial direction with respect to the small diameter portion 2, the configurations of the above-mentioned embodiments and the like can be applied.

[0088] (Verification related to the embodiment) The following verifications were performed as verifications related to the embodiments. In the verifications, as Example 1, a web W was transported using a transport roller 1 having a configuration similar to that of the first embodiment. At this time, the transport roller 1 was rotated around the rotation axis R, and the transported web W was brought into contact with the outer circumferential surface of the small diameter portion 2. Then, while the web W was being transported, the pressure distribution inside the transport roller 1 and around the transport roller 1 was measured.

[0089] FIG. 13 shows the results of measuring the pressure distribution inside and around the conveying roller 1 in verification example 1. In FIG. 13, the pressure distribution is shown in grayscale, with the closer to white (brighter) the area, the lower the pressure, and the closer to black (darker) the area, the higher the pressure. As shown in FIG. 13, it was confirmed that when the conveying roller 1 having the same configuration as the first embodiment is rotated, a negative pressure state occurs inside the small diameter portion 2, where the air pressure is lower than that outside the conveying roller 1. For this reason, it was confirmed that air flows from the outside of the conveying roller 1 through each of the holes 16 into the inside of the small diameter portion 2, and a suction force toward the inside of the small diameter portion 2 acts on the web.

[0090] In the verification, as Comparative Example 1, a conveying roller was formed in which the diameter of the portion corresponding to the large diameter portion 3 was reduced from the configuration of Example 1, and the portion corresponding to the large diameter portion 3 and the small diameter portion 2 had the same or approximately the same outer diameter. Then, a web was conveyed using the conveying roller in which the portion corresponding to the large diameter portion 3 and the small diameter portion 2 had the same or approximately the same outer diameter. In Comparative Example 1, it was confirmed that, while the web was being conveyed, no negative pressure state was generated inside the small diameter portion 2, and suction force toward the inside of the small diameter portion 2 did not act on the web.

[0091] According to at least one of these embodiments or examples, in the conveying roller, the communicating cavity communicates between the first hole in the small diameter portion and the second hole in the large diameter portion, and is formed from the inside of the small diameter portion to the inside of the large diameter portion. The communicating cavity is closed to the outside in areas other than the first hole and the second hole. This makes it possible to provide a conveying roller that prevents the web from lifting up from the conveying roller without providing a suction drive unit, and a roller unit including the conveying roller.

[0092] Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and spirit of the invention, and are included in the scope of the invention and its equivalents described in the claims. [Explanation of symbols]

[0093] 1...conveying roller, 2...small diameter portion, 3...large diameter portion, 13...partition wall (first partition wall), 15...extended flow path (first extended flow path), 16...hole (first hole), 26...extended wall (second partition wall), 28...hole (second hole), 30...communicating cavity, 40...roller unit, 41...shaft, 42...shaft body, 45...protruding plate portion, 50...bearing.

Claims

1. a small diameter portion in which a first hole is formed from an outer circumferential surface toward an inner circumferential surface; a large diameter portion that is provided offset from the small diameter portion in an axial direction along the rotation axis, has an outer diameter larger than that of the small diameter portion, and has a second hole formed from an outer peripheral surface toward the inner peripheral side; Equipped with a communication cavity that communicates between the first hole and the second hole is formed from the inside of the small diameter portion to the inside of the large diameter portion, The communication cavity is closed to the outside at a portion other than the first hole and the second hole. Conveying roller.

2. the small diameter portion includes a partition wall that divides a portion of the communication cavity formed inside the small diameter portion into a plurality of extended flow paths, Each of the plurality of extended flow paths opens to an outer circumferential side through the first hole. The transport roller of claim 1.

3. the large diameter portion includes an extension wall provided at a portion of the communication cavity formed inside the large diameter portion, The extension wall extends from the inner periphery side toward the outer periphery side and has an arc shape in a cross section perpendicular to the axial direction. The transport roller of claim 1.

4. A plurality of first holes are formed in the small diameter portion as the first hole, The first holes are arranged in a circumferential direction, Each of the plurality of first holes has a dimension along the circumferential direction that is larger than a dimension along the axial direction. The transport roller of claim 1.

5. A conveying roller according to any one of claims 1 to 4, a shaft supporting the conveying roller from the inner circumferential side; a bearing that connects the conveying roller to the shaft so that the conveying roller can rotate relative to the shaft about the rotation axis; Equipped with The shaft is a shaft body extending along the axial direction of the conveying roller; a protruding plate portion that is disposed in a portion of the communication cavity that is formed inside the large diameter portion and that protrudes from the shaft body toward an outer periphery; A roller unit comprising:

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