Travel position adjustment cap and curve conveyor

Abstract

The present invention provides a travel position adjustment cap and a curved conveyor that can easily improve the travel stability of a curved belt without changing the configuration of the outer and inner frames. [Solution] The travel position adjustment cap 20 is used in a curved conveyor 10 that travels a curved belt 13, which is wrapped around a pair of rollers 12a and 12e that are rotatably supported on an outer frame 14 and an inner frame that are arc-shaped in plan view, in an arc shape in plan view. The travel position adjustment cap 20 is attached to at least one of the outer frame 14 and the inner frame and comprises a cap body 21 that rotatably supports at least one of the pair of rollers 12a and 12e. The cap body 21 adjusts the travel position of the curved belt 13 by supporting the roller shaft 16 of at least one of the pair of rollers 12a and 12e in a position where it is moved in the slackening direction A of the curved belt 13.

Description

Technical Field

[0001] The present invention relates to a travel position adjustment cap and a curved conveyor. Background Art

[0002] Curved conveyors have been proposed as belt conveyors for conveying articles along arcuate trajectories, and have already been put into practical use (see, for example, Patent Document 1).

[0003] In the curved conveyor of Patent Document 1, a curved belt is wound around a pair of rotatable rollers arranged such that their axial centers intersect each other at a predetermined angle, the curved belt is caused to travel by rotation of the rollers, and articles on the curved belt are conveyed. The curved conveyor of Patent Document 1 includes a pair of side girder frames connecting respective end portions of an arcuate outer frame and an arcuate inner frame, a roller position adjustment plate disposed opposite the side girder frames, and a roller bearing portion protruding from the roller position adjustment plate and rotatably supporting the roller. In the curved conveyor of Patent Document 1, the distance in the circumferential direction of the apparatus between the pair of rollers is adjusted by adjusting the distance in the circumferential direction of the apparatus between the side girder frames and the roller position adjustment plate using a spacing adjustment means formed of a bolt and a nut, thereby optimizing the tension of the curved belt wound around the pair of rollers. Prior Art Documents Patent Documents

[0004] Patent Document 1 Japanese Unexamined Patent Application Publication No. 2011-246247 Summary of the Invention Problem to be Solved by the Invention

[0005] In a curved conveyor, a force directed toward the inner peripheral side acts on the traveling curved belt, which may cause the curved belt to move toward the inner peripheral side and slip off the rollers, resulting in unstable travel of the curved belt.

[0006] However, in the curved conveyor described in Patent Document 1, in order to stabilize the movement of the curved belt, it is necessary to change the configuration of the outer frame and inner frame, such as changing the shape and dimensions of the outer frame and inner frame that rotatably support the rollers, and the existing configuration cannot be used as is, which presents a problem as it requires the redesign of the outer frame and inner frame.

[0007] The present invention has been made in view of the above circumstances, and aims to provide a running position adjustment cap and a curved conveyor that can easily improve the running stability of a curved belt without changing the configuration of the outer frame and the inner frame. [Means for solving the problem]

[0008] To achieve the above objective, the travel position adjustment cap of the present invention is used in a curved conveyor comprising an outer frame and an inner frame that are arc-shaped in plan view, a plurality of rollers arranged radially in plan view and rotatably supported by the outer frame and the inner frame, and a curved belt that is wrapped around each of a pair of rollers located at both ends of the plurality of rollers and travels in an arc shape in plan view, and comprises a cap body attached to at least one of the outer frame and the inner frame and rotatably supporting at least one of the pair of rollers, wherein the travel position of the curved belt is adjusted by supporting the roller shaft of at least one of the pair of rollers in a position moved in the slack direction and / or vertical direction of the curved belt.

[0009] The curved conveyor of the present invention comprises an outer frame and an inner frame that are arc-shaped in plan view, a plurality of rollers arranged radially in plan view, a curved belt that is wrapped around each of a pair of rollers located at both ends of the plurality of rollers and travels in an arc shape in plan view, and a plurality of shaft core caps attached to the outer frame and the inner frame that rotatably support the pair of rollers, wherein at least one of the plurality of shaft core caps is the travel position adjustment cap described above. [Effects of the Invention]

[0010] According to the present invention, the running stability of the curved belt can be easily improved without changing the configuration of the outer frame and the inner frame. [Brief explanation of the drawing]

[0011] [Figure 1] This is a plan view of the curved conveyor according to the embodiment. [Figure 2] This is a cross-sectional view along line 2-2 shown in Figure 1. [Figure 3] This is a front view of a curved conveyor according to an embodiment. [Figure 4A] This is a front view of the travel position adjustment cap according to the embodiment. [Figure 4B] This is a rear view of the travel position adjustment cap according to the embodiment. [Figure 4C] This is a plan view of the travel position adjustment cap according to the embodiment. [Figure 4D] This is a right side view of the travel position adjustment cap according to the embodiment. [Figure 4E] This is a cross-sectional view along the line 4E-4E in Figure 4A. [Figure 5] This is an explanatory diagram illustrating how to attach the running position adjustment cap to the roller. [Figure 6A] This is a front view of the travel position adjustment cap according to a first modified example of the embodiment. [Figure 6B] This is a rear view of the travel position adjustment cap according to a first modified embodiment. [Figure 6C] It is a plan view of a travel position adjustment cap according to a first modification of the embodiment. [Figure 6D] It is a right side view of the travel position adjustment cap according to the first modification of the embodiment. [Figure 6E] It is a cross-sectional view along line 6E-6E in FIG. 6A. [Figure 7A] It is a front view of a travel position adjustment cap according to a second modification of the embodiment. [Figure 7B] It is a rear view of the travel position adjustment cap according to the second modification of the embodiment. [Figure 7C] It is a plan view of the travel position adjustment cap according to the second modification of the embodiment. [Figure 7D] It is a right side view of the travel position adjustment cap according to the second modification of the embodiment. [Figure 7E] It is a cross-sectional view along line 7E-7E in FIG. 7A. [Figure 8A] It is a front view of a travel position adjustment cap according to a third modification of the embodiment. [Figure 8B] It is a rear view of the travel position adjustment cap according to the third modification of the embodiment. [Figure 8C] It is a plan view of the travel position adjustment cap according to the third modification of the embodiment. [Figure 8D] It is a right side view of the travel position adjustment cap according to the third modification of the embodiment. [Figure 8E] It is a cross-sectional view along line 8E-8E in FIG. 8A. [Figure 9] It is an explanatory diagram illustrating a mode of attaching the travel position adjustment cap according to the third modification of the embodiment to a roller. [Figure 10] It is an explanatory diagram illustrating results of a curved belt travel position evaluation test using the travel position adjustment cap according to the embodiment. MODE FOR CARRYING OUT THE INVENTION

[0012] One embodiment of the present invention will be described in detail with reference to the following drawings. In the following description, the same reference numerals will be used for identical components, and redundant descriptions will be omitted.

[0013] 1. Embodiment 1-1. Configuration of a curved conveyor Figure 1 is a plan view of a curved conveyor 10 according to an embodiment. In Figure 1, the curved conveyor 10 transports an unshown object along a curved path (transport route). The curved conveyor 10 comprises a plurality of rotatable rollers 12a to 12e arranged radially in a plan view, and a curved belt 13. The curved belt 13 is wrapped around the roller 12a located furthest downstream (left end in Figure 1) in the transport direction for transporting the object, and the roller 12e located furthest upstream (right end in Figure 1). Therefore, the curved belt 13 is stretched between rollers 12a and 12e so as to sandwich the rollers 12b to 12d between rollers 12a and 12e from above and below. Due to the rotation of these rollers 12a and 12e, the curved belt 13 travels along an arc-shaped trajectory. Note that roller 12a is a tail roller, roller 12e is a head roller, and rollers 12b to 12d are intermediate rollers. In addition, support plates may be provided instead of, or in addition to, the intermediate rollers 12b to 12d.

[0014] In the curve conveyor 10, following the analogy of the inner and outer circumferences of the curve belt 13 which travels in an arc, the side further from the center of the arc-shaped trajectory of the curve belt 13 (hereinafter referred to as the trajectory center) in the radial direction is called the outer circumference, and the side closer to the center (the upper side of the paper in Figure 1) is called the inner circumference. On the curve belt 13, the surface that is the forward path portion traveling from upstream to downstream in the conveying direction is called the top surface, and the surface that is the return path portion traveling from downstream to upstream in the conveying direction is called the bottom surface. Conveyed objects can be placed on the top surface of the curve belt 13. In Figure 1, the direction of travel on the top surface of the curve belt 13 is indicated by a white arrow.

[0015] The curved conveyor 10 comprises an outer frame 14 and an inner frame 15 that are arranged parallel to each other and have an arc shape in plan view. The outer frame 14 and the inner frame 15 are positioned along the arc-shaped trajectory of the curved belt 13. Multiple rollers 12a to 12e are arranged radially in plan view and are rotatably supported by the outer frame 14 and the inner frame 15. The outer frame 14 is positioned on the outer circumference side of the arc-shaped trajectory of the curved belt 13, and the inner frame 15 is positioned on the inner circumference side. The rollers 12a to 12e are arranged radially in plan view, with their axes extending radially from the center of the trajectory of the curved belt 13, and adjacent roller axes 16 forming a predetermined pitch angle (center angle). That is, the axes of the rollers 12a to 12e (tail roller, head roller, and intermediate roller) intersect each other at the center of the trajectory. The outer circumference ends of the roller shafts 16 of these rollers 12a to 12e are attached to the outer frame 14, and the inner circumference ends of the roller shafts 16 are attached to the inner frame 15. The outer frame 14 and the inner frame 15 are provided with holes or notches (not shown) into which the roller shafts 16 can be inserted. In this embodiment, the outer frame 14 is provided with holes, and the inner frame 15 is provided with notches.

[0016] Roller 12a is configured by fitting a sleeve 18 onto a roller body 17a. Similarly, roller 12e is configured by fitting a sleeve 18 onto a roller body 17e. The other rollers 12b to 12d are configured without sleeves 18 on the roller bodies 17b to 17d. In this example, roller bodies 17a to 17e are the same shape and size. In the following description, unless there is a need to distinguish between individual rollers 12a to 12e, they will be referred to as roller 12. Similarly, unless there is a need to distinguish between individual roller bodies 17a to 17e, they will be referred to collectively as roller body 17. The roller shaft 16 protrudes from both ends of the roller body 17 and constitutes the shaft of roller 12. Roller 12 is configured so that the roller body 17 can rotate around the roller shaft 16. The shape of the roller shaft 16 when viewed from its axial direction (hereinafter also referred to as the shape of the roller shaft) is hexagonal in this embodiment. The shape of the roller shaft 16 when viewed from its axial direction is not limited to a hexagon, but may be a polygon other than a hexagon, a circle, an ellipse, an oblong, etc. A polygon includes a rounded corner shape where the corners are rounded by an arc. An oblong includes a shape where a pair of arcs are connected by a pair of straight lines. In this embodiment, the sleeve 18 is fitted onto the tail roller 12a and the head roller 12e, but is not limited to this, and may be fitted onto at least one of the tail roller 12a and the head roller 12e.

[0017] The roller body 17 is a tapered roller having a tapered shape in which the roller diameter decreases linearly toward the inner circumference (becoming narrower towards the end). In this example, the roller body 17 is made of a metal such as stainless steel (SUS) or aluminum alloy. The roller body 17 may also be a straight roller having a uniform outer diameter along its entire length in the axial direction, to which a tapered tube is attached that decreases linearly toward one end in the axial direction to create a tapered shape. In this disclosure, "uniform" includes not only cases where it is perfectly uniform, but also cases where it is substantially uniform, that is, cases where it differs within a range that does not depart from the spirit of the invention (for example, cases where it differs within the tolerance range specified at the time of design).

[0018] For example, the curved conveyor 10 is a roller conveyor with the aforementioned curved belt 13 and sleeve 18 attached, and the rollers 12a to 12e rotate simultaneously and in the same direction by a driving force from a drive source such as a roller (referred to as a motor roller) that has an electric motor built in (not shown). The rollers 12a to 12e are connected to each other by, for example, a power belt, and a driving force is supplied to any of the rollers 12 from the drive source. In this embodiment, the driving force is supplied to the roller 12e, which is the head roller, from the drive source. As a result, the rollers 12a to 12e rotate as described above. The drive source is connected to, for example, at least one of the outer frame 14 on the outer circumference side and the inner frame 15 on the inner circumference side.

[0019] In this example, roller 12a is driven by a power source, but roller 12e may also be driven by a power source, or both roller 12a and roller 12e may be driven by a power source. The rollers 12 other than roller 12a and / or roller 12e that are driven by a power source function as driven rollers that rotate by contacting the moving curve belt 13. In addition, although the curve conveyor 10 in this example has five rollers 12, the number of rollers 12 can be two or more.

[0020] The curved belt 13 is wrapped around a pair of rollers 12a and 12e (tail roller and head roller) located at both ends of a plurality of rollers 12a to 12e, and runs in an arc shape in plan view. When wrapped around rollers 12a and 12e, the curved belt 13 has an annular sector shape in plan view. An annular sector is the shape of a region cut from a ring shape enclosed by two concentric circles by two straight lines in the radial direction of those concentric circles. In other words, an annular sector is the shape obtained by cutting a smaller sector from a larger sector that has the same central angle and a common center. In the following explanation, the radial direction of the above concentric circles will be referred to as the radial direction of the annular sector. This curved belt 13 is manufactured by connecting the ends (straight lines) of annular sector sheets of uniform thickness throughout the entire area so that it has the same shape as the circumferential surface of a frustocone (funnel shape). Therefore, the unfolded shape of the curved belt 13, when cut along the radial direction of the annular sector which is its width, is also an annular sector.

[0021] The curved belt 13 can be a belt composed solely of resin layers made of thermoplastic resins such as polyurethane, polyvinyl chloride, or polyolefin, without, for example, a laminated fiber layer made of canvas or the like. As a curved belt 13 composed solely of resin layers without a laminated fiber layer, for example, a multilayer resin layer can be applied in which a resin layer made of a thermoplastic resin such as polyurethane and a conductive layer (another resin layer) made of a resin to which a conductive agent and a crosslinking agent have been added can be laminated. However, the curved belt 13 is not limited to this, and various other curved belts may be used, for example, a belt in which a resin layer made of thermoplastic resin and a canvas core made of polyester fibers, nylon fibers, aromatic polyamide fibers, etc., are laminated.

[0022] As described above, among the rollers 12a to 12e, the tail roller 12a and the head roller 12e around which the curved belt 13 is wound are fitted with sleeves 18 to prevent meandering and uneven running of the curved belt 13 and to stabilize its movement. Each sleeve 18 is provided on the roller body 17a, 17e and contacts the curved belt 13. The sleeve 18 has a hollow cylindrical or frustoconical shape. The sleeve 18 is made of, for example, resin or rubber. By providing sleeves 18 on the roller body 17a, 17e, the crown effect caused by the localized enlargement of the rollers 12a, 12e by the sleeves 18 and the frictional force due to the contact between the curved belt 13 and the sleeves 18 effectively suppresses meandering and uneven running of the curved belt 13, thereby improving running stability.

[0023] The method for fixing the sleeve 18 to the roller body 17a is not limited. For example, the sleeve 18, made of an elastically deformable material, may be elastically deformed to widen its inner diameter and fitted onto the roller body 17a, and then the sleeve 18 may be fixed to the roller body 17a by tightening the roller body 17a with its elastic force. In this case, the inner diameter of the sleeve 18 is made smaller than the outer diameter of the roller body 17a.

[0024] The higher the coefficient of dynamic friction between the surface of the sleeve 18 and the surface of the curved belt 13, the better the running stability of the curved belt 13. For example, the material of the sleeve 18 should be one that increases the coefficient of dynamic friction between it and the curved belt 13.

[0025] The coefficient of dynamic friction between the surface of the sleeve 18 and the surface of the curved belt 13 is preferably within the range of 0.3 to 2.0. If the coefficient of dynamic friction between the surface of the sleeve 18 and the surface of the curved belt 13 is less than 0.3, sufficient frictional force will not be generated between the curved belt 13 and the sleeve 18, and the movement of the curved belt 13 will become unstable. On the other hand, if the coefficient of dynamic friction between the surface of the sleeve 18 and the surface of the curved belt 13 exceeds 2.0, the hardness of either the curved belt 13 or the sleeve 18, or both, will decrease, so wear due to sliding between the surface of the sleeve 18 and the surface of the curved belt 13 will progress, and the durability of the curved belt 13 and the sleeve 18 will decrease.

[0026] From the above perspective, in order to further improve the running stability of the curved belt 13, it is preferable to set the coefficient of dynamic friction between the surface of the sleeve 18 and the surface of the curved belt 13 within the range of 0.3 to 2.0, as described above. However, if the hardness of either the curved belt 13 or the sleeve 18 is significantly higher than the hardness of the other, the wear on the less hard side may become more severe, potentially reducing its durability. For this reason, from the standpoint of durability, it is preferable that the hardness of the surface of the sleeve 18 and the surface of the curved belt 13 be close to each other.

[0027] To improve the running stability of the curved belt 13, it is preferable to position the sleeve 18 on the roller body 17 such that its inner edge is located within a range of 1% to 50% of the width of the curved belt 13 from the outer edge of the curved belt 13. More preferably, the sleeve 18 is positioned so that its inner edge is located within a range of 1% to 25%, more preferably 5% to 25%, and even more preferably 10% to 20%, of the width of the curved belt 13 from the outer edge of the curved belt 13.

[0028] The closer the portion of the curved belt 13 that the sleeve 18 contacts is to the outer edge of the curved belt 13, the more stable the running position of the curved belt 13 becomes due to the crown effect. On the other hand, the further the sleeve 18 is from the outer edge of the curved belt 13, the less likely the curved belt 13 is to come off the sleeve 18, ensuring that the crown effect and the required frictional force between the surface of the sleeve 18 and the surface of the curved belt 13 are obtained, and preventing the curved belt 13 from coming off the roller 12. Therefore, by setting the position of the inner edge of the sleeve 18 relative to the outer edge of the curved belt 13 within the above range, high running stability of the curved belt 13 can be ensured. The running position of the curved belt 13 is the running position of the outer edge of the curved belt 13, and can be measured as the distance from the outer edge of the roller 12 to the outer edge of the curved belt 13.

[0029] 1-2. Configuration of the running position adjustment cap Figure 2 is a cross-sectional view along line 2-2 shown in Figure 1. Figure 3 is a front view of the curved conveyor 10. In Figure 3, the curved conveyor 10 shows the pair of rollers 12a and 12e located at both ends of the plurality of rollers 12a to 12e, and omits the illustration of the other rollers 12b to 12d. As shown in Figures 2 and 3, the curved conveyor 10 is equipped with a running position adjustment cap 20 for adjusting the running position of the curved belt 13. The running position adjustment cap 20 is attached to at least one of the outer frame 14 and the inner frame 15 and includes a cap body 21 that rotatably supports at least one of the pair of rollers 12a and 12e. The cap body 21 adjusts the running position of the curved belt 13 by supporting the roller shaft 16 of at least one of the pair of rollers 12a and 12e in a position moved in the slack direction A and / or vertical direction C of the curved belt 13. In this embodiment, the curved conveyor 10 is equipped with four running position adjustment caps 20, which are attached to the outer and inner ends of the roller shaft 16 of the tail roller 12a, and to the outer and inner ends of the roller shaft 16 of the head roller 12e. Each cap body 21 of the four running position adjustment caps 20 supports the roller shafts 16 of the pair of rollers 12a and 12e in a position where they are moved in the slack direction A of the curved belt 13. Since the four running position adjustment caps 20 have the same configuration as each other, in the following description, only one running position adjustment cap 20 attached to the outer end of the roller shaft 16 of roller 12a will be described, and the other three running position adjustment caps 20 will not be described.

[0030] In the curved conveyor 10, the loosening direction A is the direction in which the curved belt 13 is loosened as the tail roller (roller 12a) and the head roller (roller 12e) move closer together, and the tensioning direction B is the direction opposite to the loosening direction A, and is the direction in which the curved belt 13 is tensioned as the head roller and the tail roller move further apart. When the direction of travel of the upper surface of the curved belt 13 is taken as the reference, at the roller 12a, the positive (+) direction along the direction of travel of the upper surface of the curved belt 13 is the loosening direction A, and the negative (-) direction opposite to the direction of travel of the upper surface of the curved belt 13 is the tensioning direction B. At the roller 12e, the negative (-) direction opposite to the direction of travel of the upper surface of the curved belt 13 is the loosening direction A, and the positive (+) direction along the direction of travel of the upper surface of the curved belt 13 is the tensioning direction B. The vertical direction C is the direction perpendicular to the loosening direction A and the tensioning direction B. In this embodiment, the upper surface of the curved belt 13 extends along the horizontal direction, the loosening direction A and the tensioning direction B coincide with the horizontal direction, and the vertical direction C coincides with the vertical direction.

[0031] The outer frame 14 has bent portions that are folded outwards at both ends in the vertical direction C, which is perpendicular to the loosening direction A and the tensioning direction B. The inner frame 15 has bent portions that are folded inwards at both ends in the vertical direction C, which is perpendicular to the loosening direction A and the tensioning direction B.

[0032] Figure 4A is a front view of the running position adjustment cap 20. Figure 4B is a rear view of the running position adjustment cap 20. Figure 4C is a top view of the running position adjustment cap 20. Figure 4D is a right side view of the running position adjustment cap 20. Figure 4E is a cross-sectional view along the line 4E-4E in Figure 4A. As shown in Figures 4A to 4E, the cap body 21 of the running position adjustment cap 20 has a side wall portion 22 and a roller shaft insertion portion 23 into which the roller shaft 16 can be inserted. The running position adjustment cap 20 is made of a flexible material, such as a resin such as PP (polypropylene), or a metal such as an aluminum alloy.

[0033] The side wall portion 22 is formed in a cylindrical shape. In this embodiment, the side wall portion 22 is formed in a closed-bottom cylindrical shape with one end in the axial direction of the side wall portion 22 closed and the other end open. The shape of the side wall portion 22 when viewed from the front (hereinafter also referred to as the shape of the side wall portion) is oval in Figure 4A. The outer circumferential surface of the side wall portion 22 is composed of a pair of flat portions and a pair of curved portions connecting the pair of flat portions. The shape of the side wall portion 22 when viewed from the front is not limited to oval, but may be circular, elliptical, polygonal, etc.

[0034] The side wall portion 22 has an opening 24 that opens up a part of the side wall portion 22 in the circumferential direction. In this embodiment, the opening 24 is provided on one of a pair of planar portions that constitute the outer circumferential surface of the side wall portion 22. The opening 24 is not limited to being provided on a planar portion of the side wall portion 22, but may also be provided on a curved portion.

[0035] The roller shaft insertion portion 23 is formed in a cylindrical shape. The roller shaft insertion portion 23 is composed of the inner circumferential surface of the side wall portion 22 and communicates with the opening at the other end of the side wall portion 22. The center position of the roller shaft insertion portion 23 is offset from the center position of the side wall portion 22. More specifically, the center position of the roller shaft insertion portion 23 is offset from the center position of the side wall portion 22 toward the opening 24. When the running position adjustment cap 20 is attached to the outer frame 14 or the inner frame 15, the opening 24 is oriented toward the loosening direction A of the curved belt 13. That is, the roller shaft insertion portion 23 is provided at a position offset in the loosening direction A with respect to the center position of the side wall portion 22. The shape of the roller shaft insertion portion 23 when viewed from the rear (hereinafter also referred to as the shape of the roller shaft insertion portion) is hexagonal in Figure 4B. The inner circumferential surface of the roller shaft insertion portion 23 has a configuration in which three pairs of opposing flat surfaces are provided. The shape of the roller shaft insertion portion 23 when viewed from the rear is not limited to a hexagon; it may also be a polygon other than a hexagon, a circle, an ellipse, an oblong, etc.

[0036] As shown in Figure 4E, the side wall portion 22 has a central axis O1 extending along its axial direction. The central axis O1 of the side wall portion 22 passes through the center position of the side wall portion 22. In this example, the center position of the side wall portion 22 is the center of the circumscribed circle of the side wall portion 22. The roller shaft insertion portion 23 has a central axis O2 extending along its axial direction. The central axis O2 of the roller shaft insertion portion 23 passes through the center position of the roller shaft insertion portion 23. In this example, the center position of the roller shaft insertion portion 23 is the center of the circumscribed circle of the roller shaft insertion portion 23. The central axis O1 of the side wall portion 22 and the central axis O2 of the roller shaft insertion portion 23 are parallel. The distance X between the central axis O1 of the side wall portion 22 and the central axis O2 of the roller shaft insertion portion 23 is 1.2 mm in this example, but is not limited to this. In this embodiment, the travel position adjustment cap 20 has an opening 24 that penetrates the side wall portion 22 in its radial direction, so the distance X between the central axis O1 of the side wall portion 22 and the central axis O2 of the roller shaft insertion portion 23 is the maximum value X max This is the result. Maximum value X max This can be expressed by the following equation (1). X max =(L1-L2) / 2 ···(1) In the above equation (1), L1 is the radial length of the side wall portion 22 (see Figures 4A and 4E), and L2 is the radial length of the roller shaft insertion portion 23 (see Figures 4B and 4E). The radial direction of the side wall portion 22 is perpendicular to the axial direction of the side wall portion 22. The radial direction of the roller shaft insertion portion 23 is perpendicular to the axial direction of the roller shaft insertion portion 23. In this embodiment, the radial direction of the side wall portion 22 and the radial direction of the roller shaft insertion portion 23 are in the direction along the slack direction A of the curved belt 13. The radial length L1 of the side wall portion 22 and the radial length L2 of the roller shaft insertion portion 23 satisfy the relationship L1 > L2. For example, the radial length L1 of the side wall portion 22 may be 13.4 mm, and the radial length L2 of the roller shaft insertion portion 23 may be 11.0 mm.

[0037] The side wall portion 22 has different thicknesses in the circumferential direction of the side wall portion 22. In FIG. 4B, the outer circumferential surface of the side wall portion 22 is indicated by a two-dot chain line, and the inner circumferential surface of the roller shaft insertion portion 23 is indicated by a solid line. The region enclosed by the two-dot chain line and the solid line corresponds to the thickness of the side wall portion 22 in the circumferential direction. The thickness of the side wall portion 22 includes zero.

[0038] As shown in FIG. 4E, when W1 is the thickness of the opening 24 of the side wall portion 22, and W2 is the thickness of the wall portion 25 on the opposite side of the opening 24 across the central axis O1 of the side wall portion 22, in the side wall portion 22, the thickness W1 of the opening 24 is smaller than the thickness W2 of the wall portion 25 on the opposite side of the opening 24 across the central axis O1 of the side wall portion 22. That is, in the side wall portion 22, the thickness W1 of the opening 24 and the thickness W2 of the wall portion 25 on the opposite side of the opening 24 across the central axis O1 of the side wall portion 22 satisfy the relationship W1 < W2. In this example, the thickness W1 of the opening 24 is 0, and the thickness W2 of the wall portion 25 opposite to the opening 24 is 2.4 mm. The thickness W2 of the wall portion 25 at this time corresponds to a value obtained by subtracting the length L2 in the radial direction of the roller shaft insertion portion 23 from the length L1 in the radial direction of the side wall portion 22.

[0039] The travel position adjusting cap 20 includes a flange portion 26. The flange portion 26 is provided at the other end of the side wall portion 22 and protrudes outward in the radial direction of the side wall portion 22. The shape when the flange portion 26 is viewed from the front (hereinafter also referred to as the shape of the flange portion) is circular in FIG. 4A. The shape when the flange portion 26 is viewed from the front is not limited to being circular, and may also be elliptical, oblong, polygonal, or the like.

[0040] In this embodiment, the curved conveyor 10 is equipped with multiple shaft core caps attached to the outer frame 14 and the inner frame 15, which rotatably support the rollers 12b to 12d (intermediate rollers) other than the pair of rollers 12a and 12e located at both ends of the plurality of rollers 12a to 12e. Each shaft core cap has the same configuration as the others. The shaft core cap has a side wall portion and a roller shaft insertion portion. The shaft core cap differs from the running position adjustment cap 20 in this embodiment in that the shaft core cap does not have an opening in the circumferential direction of the side wall portion, and the center position of the roller shaft insertion portion is at the same position as the center position of the side wall portion. The shaft core caps are detachably attached to the outer or inner circumferential ends of the roller shafts 16 of the rollers 12b to 12d. The shaft core caps are inserted into holes in the outer frame 14 or notches in the inner frame 15. The shaft core caps are also referred to as bearings.

[0041] 1-3. Operation and Effects of Curved Conveyors Figure 5 is an explanatory diagram illustrating how the running position adjustment cap 20 is attached to the roller 12a. In Figure 5, the front of the paper is the loosening direction A, and the back of the paper is the tensioning direction B. Figure 5 shows the side view (right side) of the running position adjustment cap 20 and the roller 12a as seen in the tensioning direction B, as well as the cross-section of the curved belt 13 and the outer frame 14. This explanation describes the case where the running position adjustment cap 20 is attached to the roller 12a (tail roller), but the same applies when the running position adjustment cap 20 is attached to the roller 12e (head roller).

[0042] As shown in Figure 5, the running position adjustment cap 20 has an opening 24 in the side wall portion 22 oriented in the loosening direction A (towards the front of the paper in Figure 5). The roller shaft insertion portion 23 is provided at a position offset in the loosening direction A with respect to the center position of the side wall portion 22. The roller shaft 16 of the roller 12a is inserted into the roller shaft insertion portion 23. In this embodiment, the shape of the roller shaft insertion portion 23 and the shape of the roller shaft 16 are designed to be hexagonal so that the roller shaft 16 can be press-fitted into the roller shaft insertion portion 23 and fixed in place.

[0043] The opening 24 in the side wall portion 22 exposes the roller shaft 16 inserted into the roller shaft insertion portion 23. That is, the side wall portion 22 has an opening 24 on the side of the loosening direction A that exposes the roller shaft 16 inserted into the roller shaft insertion portion 23.

[0044] The running position adjustment cap 20 is fitted into the hole 14a of the outer frame 14 by inserting the side wall portion 22 constituting the cap body 21 into the hole 14a of the outer frame 14 with the opening 24 facing the loosening direction A. In this embodiment, the shape of the hole 14a of the outer frame 14 when viewed from the front (hereinafter also referred to as the shape of the hole in the outer frame) is oval. In this embodiment, the shape of the side wall portion 22 and the shape of the hole 14a of the outer frame 14 are designed to be oval so that the side wall portion 22 can be press-fitted into the hole 14a of the outer frame 14 and fixed in place. The shape of the hole 14a of the outer frame 14 when viewed from the front is not limited to oval, but may be circular, elliptical, polygonal, etc. By bringing the flange portion 26 provided at the other end of the side wall portion 22 into contact with the inner circumferential surface of the outer frame 14, the roller shaft 16 of the roller 12a can be attached to the outer frame 14 via the running position adjustment cap 20 (see Figure 2). Although not shown in the diagram, when the cap body 21 is attached to the inner frame 15, the running position adjustment cap 20 is inserted into the notch of the inner frame 15 and fitted with the side wall portion 22 of the cap body 21 facing the opening 24 in the loosening direction A. By bringing the flange portion 26 provided at the other end of the side wall portion 22 into contact with the outer surface of the inner frame 15, the roller shaft 16 of the roller 12a can be attached to the inner frame 15 via the running position adjustment cap 20 (see Figure 2).

[0045] The curved conveyor 10 according to this embodiment is equipped with a travel position adjustment cap 20. The travel position adjustment cap 20 is attached to the outer frame 14 and the inner frame 15 and includes a cap body 21 that rotatably supports a pair of rollers 12a and 12e (tail roller and head roller) located at both ends of a plurality of rollers 12a to 12e. The cap body 21 adjusts the travel position of the curved belt 13 by supporting both roller shafts 16 of the pair of rollers 12a and 12e in a position moved in the slack direction A of the curved belt 13. By including the cap body 21, the travel position adjustment cap 20 can effectively suppress movement of the curved belt 13 toward the inner circumference, thereby preventing meandering and uneven travel of the curved belt 13. Therefore, the travel position adjustment cap 20 and the curved conveyor 10 equipped with it can easily improve the travel stability of the curved belt 13 without changing the configuration of the outer frame 14 and the inner frame 15. Furthermore, the travel stability of the curved belt 13 can be improved regardless of the type of roller conveyor, the size of the curved belt 13, or external environmental factors.

[0046] The cap body 21 of the running position adjustment cap 20 has a side wall portion 22 and a roller shaft insertion portion 23 into which a roller shaft 16 can be inserted. The roller shaft insertion portion 23 is provided at a position offset in the loosening direction A with respect to the center position of the side wall portion 22. The running position adjustment cap 20 is configured to be easily attached to and detached from a pair of rollers 12a and 12e. The running position adjustment cap 20 and the curved conveyor 10 equipped therewith allow the position of the roller shaft 16 to be easily changed by replacing or changing the orientation of the running position adjustment cap 20, thereby easily improving the running stability of the curved belt 13.

[0047] The side wall portion 22 has an opening 24 on the loosening direction A side of the side wall portion 22 that exposes the roller shaft 16 inserted into the roller shaft insertion portion 23. In the running position adjustment cap 20 and the curve conveyor 10 equipped therewith, rattle and distortion are suppressed because the roller shaft 16 exposed through the opening 24 of the side wall portion 22 directly contacts the outer frame 14.

[0048] Furthermore, the curved conveyor 10 is not limited to having four running position adjustment caps 20, but may have one or more running position adjustment caps 20. That is, the curved conveyor 10 comprises an outer frame 14 and an inner frame 15 that are arc-shaped in plan view, a plurality of rollers 12 arranged radially in plan view, a curved belt 13 that is wrapped around each of a pair of rollers 12a and 12e located at both ends of the plurality of rollers 12 and runs in an arc shape in plan view, and a plurality of shaft core caps attached to the outer frame 14 and the inner frame 15 that rotatably support the pair of rollers 12a and 12e, and at least one of the plurality of shaft core caps is a running position adjustment cap 20. The running position adjustment cap 20 adjusts the running position of the curved belt 13 by having the cap body 21 support at least one roller shaft 16 of the pair of rollers 12a and 12e in a position where the curved belt 13 is moved in the slack direction A.

[0049] 2. Modified Examples of Embodiments The travel position adjustment cap 20 according to the above embodiment has an opening 24 on the side wall portion 22 in the loosening direction A, but the configuration of the travel position adjustment cap is not limited thereto.More examples of the travel position adjustment cap 20 according to the embodiment will be described below.

[0050] 2-1. First variation Figure 6A is a front view of the travel position adjustment cap 20A according to the first modified example of the embodiment. Figure 6B is a rear view of the travel position adjustment cap 20A. Figure 6C is a top view of the travel position adjustment cap 20A. Figure 6D is a right side view of the travel position adjustment cap 20A. Figure 6E is a cross-sectional view along the line 6E-6E in Figure 6A. As shown in Figures 6A to 6E, the travel position adjustment cap 20A includes a cap body 21A. The cap body 21A adjusts the travel position of the curved belt 13 by supporting the roller shaft 16 in a position where it has been moved in the loosening direction A of the curved belt 13. The cap body 21A has a side wall portion 22A and a roller shaft insertion portion 23A into which the roller shaft 16 can be inserted. The same reference numerals are used for components that are the same as in the above embodiment, and their detailed description is omitted.

[0051] The side wall portion 22A is formed in a cylindrical shape. In this example, the side wall portion 22A is formed in a closed-bottom cylindrical shape with one end closed and the other end open in the axial direction of the side wall portion 22A. The outer surface (end face) of one end of the side wall portion 22A is composed of a flat portion. A flange portion 26 is provided at the other end of the side wall portion 22A. When viewed from the front, the shape of the side wall portion 22A is oval in Figure 6A. The outer circumferential surface of the side wall portion 22A is composed of a pair of flat portions and a pair of curved portions connecting the pair of flat portions. The shape of the side wall portion 22A when viewed from the front is not limited to oval, but may be circular, elliptical, polygonal, etc.

[0052] The side wall portion 22A has a thin-walled portion 34 in which the thickness of a part of the circumferential direction of the side wall portion 22A is thinner than the thickness of other parts. In this example, the thin-walled portion 34 is provided on one of the pair of planar portions that make up the outer circumferential surface of the side wall portion 22A. The thin-walled portion 34 is not limited to being provided on a planar portion of the side wall portion 22A, but may also be provided on a curved portion.

[0053] The roller shaft insertion portion 23A is formed in a cylindrical shape. The roller shaft insertion portion 23A is constituted by the inner peripheral surface of the side wall portion 22A, and communicates with the opening at the other end of the side wall portion 22A. The center position of the roller shaft insertion portion 23A is deviated from the center position of the side wall portion 22A. More specifically, the center position of the roller shaft insertion portion 23A is deviated from the center position of the side wall portion 22A toward the thin-walled portion 34. When the travel position adjustment cap 20A is attached to the outer frame 14 and the inner frame 15, the thin-walled portion 34 is oriented in the loosening direction A of the curved belt 13. That is, the roller shaft insertion portion 23A is provided at a position offset in the loosening direction A with respect to the center position of the side wall portion 22A. When the roller shaft insertion portion 23A is viewed from the back side, the shape thereof is a hexagon in FIG. 6B, but is not limited thereto, and may be a polygon other than a hexagon, a circle, an ellipse, an oval, or the like.

[0054] A distance X between a center axis O1 of the side wall portion 22A and a center axis O2 of the roller shaft insertion portion 23A is 1.0 mm in this example, but is not limited thereto.

[0055] As shown in FIG. 6E, when the thickness of the thin-walled portion 34 of the side wall portion 22A is W1, and the thickness of the wall portion 25 on the opposite side to the thin-walled portion 34 across the center axis O1 of the side wall portion 22A is W2, in the side wall portion 22A, the thickness W1 of the thin-walled portion 34 is smaller than the thickness W2 of the wall portion 25 on the opposite side to the thin-walled portion 34 across the center axis O1 of the side wall portion 22A. That is, in the side wall portion 22A, the thickness W1 of the thin-walled portion 34 and the thickness W2 of the wall portion 25 on the opposite side to the thin-walled portion 34 across the center axis O1 of the side wall portion 22A satisfy the relationship of W1<W2. In this example, the thickness W1 of the thin-walled portion 34 is 0.2 mm, and the thickness W2 of the wall portion 25 on the opposite side to the thin-walled portion 34 is 2.2 mm.

[0056] When attaching the travel position adjustment cap 20A to the roller 12a, the thin-walled portion 34 of the side wall portion 22A is oriented in the loosening direction A. That is, the side wall portion 22A has the thin-walled portion 34 provided on the loosening direction A side of the side wall portion 22A.

[0057] The roller shaft 16 of the roller 12a is inserted into the roller shaft insertion portion 23A. The side wall portion 22A is inserted into and fitted into the hole 14a of the outer frame 14. In this example, the shape of the side wall portion 22A and the shape of the hole 14a of the outer frame 14 are designed to be oval-shaped so that the side wall portion 22A can be press-fitted into the hole of the outer frame 14 and fixed in place. By bringing the flange portion 26 provided at the other end of the side wall portion 22A into contact with the inner circumferential surface of the outer frame 14, the roller shaft 16 of the roller 12a can be attached to the outer frame 14 via the running position adjustment cap 20A. Here, the case of attaching the running position adjustment cap 20A to the roller 12a (tail roller) has been described, but the same applies when attaching the running position adjustment cap 20A to the roller 12e (head roller).

[0058] The first modified travel position adjustment cap 20A is attached to the outer frame 14 and the inner frame 15 and includes a cap body 21A that rotatably supports a pair of rollers 12a and 12e (tail roller and head roller) located at both ends of a plurality of rollers 12a to 12e. The cap body 21A adjusts the travel position of the curved belt 13 by supporting both roller shafts 16 of the pair of rollers 12a and 12e in a position moved in the slack direction A of the curved belt 13. By including the cap body 21A, the travel position adjustment cap 20A can effectively suppress movement of the curved belt 13 toward the inner circumference and prevent meandering and uneven travel of the curved belt 13. Therefore, the travel position adjustment cap 20A and the curved conveyor equipped therewith can easily improve the travel stability of the curved belt 13 without changing the configuration of the outer frame 14 and the inner frame 15, similar to the above embodiment. Furthermore, the travel stability of the curved belt 13 can be improved regardless of the type of roller conveyor, the size of the curved belt 13, or external environmental factors.

[0059] The running position adjustment cap 20A is configured to be easily attached to and detached from a pair of rollers 12a and 12e. The running position adjustment cap 20A and the curved conveyor equipped with it allow for easy changes in the position of the roller shaft 16 by replacing or changing the orientation of the running position adjustment cap 20A, thereby easily improving the running stability of the curved belt 13.

[0060] 2-2. Second variation Figure 7A is a front view of the running position adjustment cap 20B according to a second modification of the embodiment. Figure 7B is a rear view of the running position adjustment cap 20B. Figure 7C is a top view of the running position adjustment cap 20B. Figure 7D is a right side view of the running position adjustment cap 20B. Figure 7E is a cross-sectional view along the line 7E-7E in Figure 7A. As shown in Figures 7A to 7E, the running position adjustment cap 20B includes a cap body 21B. The cap body 21B adjusts the running position of the curved belt 13 by supporting the roller shaft 16 in a position where it has been moved in the loosening direction A of the curved belt 13. The cap body 21B has a side wall portion 22B and a roller shaft insertion portion 23B into which the roller shaft 16 can be inserted. Components that are the same as those in the above embodiment and the first modification are denoted by the same reference numerals and their detailed description is omitted.

[0061] The side wall portion 22B is formed in a cylindrical shape. In this example, the side wall portion 22B is formed in a closed-bottom cylindrical shape with one end closed and the other end open in the axial direction of the side wall portion 22B. The outer surface (end face) of one end of the side wall portion 22B is composed of a curved portion. A flange portion 26 is provided at the other end of the side wall portion 22B. When viewed from the front, the shape of the side wall portion 22B is oval in Figure 7A. The outer circumferential surface of the side wall portion 22B is composed of a pair of flat portions and a pair of curved portions connecting the pair of flat portions. The shape of the side wall portion 22B when viewed from the front is not limited to oval, but may be circular, elliptical, polygonal, etc. When viewed from the front, the shape of the flange portion 26 is a square. The travel position adjustment cap 20B according to the second modification differs from the travel position adjustment cap 20A according to the first modification in that the outer surface of one end of the side wall portion 22B is composed of a curved portion, and the shape of the flange portion 26 when viewed from the front is a square.

[0062] The side wall portion 22B has a thin-walled portion 34 in which the thickness of a part of the circumferential direction of the side wall portion 22B is thinner than the thickness of other parts. In this example, the thin-walled portion 34 is provided on one of the pair of planar portions that constitute the outer circumferential surface of the side wall portion 22B. The thin-walled portion 34 is not limited to being provided on a planar portion of the side wall portion 22B, but may also be provided on a curved portion.

[0063] The roller shaft insertion portion 23B is formed in a cylindrical shape. The roller shaft insertion portion 23B is composed of the inner circumferential surface of the side wall portion 22B and communicates with the opening at the other end of the side wall portion 22B. The center position of the roller shaft insertion portion 23B is offset from the center position of the side wall portion 22B. More specifically, the center position of the roller shaft insertion portion 23B is offset from the center position of the side wall portion 22B toward the thin-walled portion 34. When the running position adjustment cap 20B is attached to the outer frame 14 and the inner frame 15, the thin-walled portion 34 is oriented toward the loosening direction A of the curved belt 13. That is, the roller shaft insertion portion 23B is provided at a position offset in the loosening direction A with respect to the center position of the side wall portion 22B. The shape of the roller shaft insertion portion 23B when viewed from the rear is hexagonal in Figure 7B, but is not limited to this, and may be a polygon other than a hexagon, a circle, an ellipse, an oblong, etc.

[0064] In this example, the distance X between the central axis O1 of the side wall portion 22B and the central axis O2 of the roller shaft insertion portion 23B is 1.0 mm, but it is not limited thereto.

[0065] As shown in FIG. 7E, when W1 is the thickness of the thin-walled portion 34 of the side wall portion 22B, and W2 is the thickness of the wall portion 25 on the opposite side to the thin-walled portion 34 across the central axis O1 of the side wall portion 22B, in the side wall portion 22B, the thickness W1 of the thin-walled portion 34 is smaller than the thickness W2 of the wall portion 25 on the opposite side to the thin-walled portion 34 across the central axis O1 of the side wall portion 22B. That is, in the side wall portion 22B, the thickness W1 of the thin-walled portion 34 and the thickness W2 of the wall portion 25 on the opposite side to the thin-walled portion 34 across the central axis O1 of the side wall portion 22B satisfy the relationship of W1 < W2. In this example, the thickness W1 of the thin-walled portion 34 is 0.2 mm, and the thickness W2 of the wall portion 25 on the opposite side to the thin-walled portion 34 is 2.2 mm.

[0066] When attaching the travel position adjustment cap 20B to the roller 12a, the thin-walled portion 34 of the side wall portion 22B is oriented in the loosening direction A. That is, the side wall portion 22B has the thin-walled portion 34 provided on the side of the side wall portion 22B in the loosening direction A.

[0067] The roller shaft 16 of the roller 12a is inserted into the roller shaft insertion portion 23B. The side wall portion 22B is inserted into and fitted to the hole 14a of the outer frame 14. In this example, the shape of the side wall portion 22B and the shape of the hole 14a of the outer frame 14 are designed to be elliptical, so that the side wall portion 22B can be press-fitted into the hole of the outer frame 14 and fixed thereby. By bringing the flange portion 26 provided at the other end of the side wall portion 22B into contact with the inner peripheral surface of the outer frame 14, the roller shaft 16 of the roller 12a can be attached to the outer frame 14 via the travel position adjustment cap 20B. Although the case where the travel position adjustment cap 20B is attached to the roller 12a (tail roller) is described herein, the same applies to the case where the travel position adjustment cap 20B is attached to the roller 12e (head roller).

[0068] The second modified travel position adjustment cap 20B is attached to the outer frame 14 and the inner frame 15 and includes a cap body 21B that rotatably supports a pair of rollers 12a and 12e (tail roller and head roller) located at both ends of the plurality of rollers 12a to 12e. The cap body 21B adjusts the travel position of the curved belt 13 by supporting both roller shafts 16 of the pair of rollers 12a and 12e in a position moved in the slack direction A of the curved belt 13. By including the cap body 21B, the travel position adjustment cap 20B can effectively suppress movement of the curved belt 13 toward the inner circumference, thereby preventing meandering and uneven travel of the curved belt 13. Therefore, the travel position adjustment cap 20B and the curved conveyor equipped therewith can easily improve the travel stability of the curved belt 13 without changing the configuration of the outer frame 14 and the inner frame 15, similar to the above embodiment. Furthermore, the travel stability of the curved belt 13 can be improved regardless of the type of roller conveyor, the size of the curved belt 13, or external environmental factors.

[0069] The running position adjustment cap 20B is configured to be easily attached to and detached from a pair of rollers 12a and 12e. The running position adjustment cap 20B and the curved conveyor equipped with it allow for easy changes in the position of the roller shaft 16 by replacing or changing the orientation of the running position adjustment cap 20B, thereby easily improving the running stability of the curved belt 13.

[0070] 2-3. Third Variation In the above embodiment, the first modification, and the second modification, the roller shaft 16 is moved in the slackening direction A of the curved belt 13, but in the third modification, the roller shaft 16 is moved in the vertical direction C of the curved belt 13.

[0071] Figure 8A is a front view of the running position adjustment cap 20C according to a third modified example of the embodiment. Figure 8B is a rear view of the running position adjustment cap 20C. Figure 8C is a top view of the running position adjustment cap 20C. Figure 8D is a right side view of the running position adjustment cap 20C. Figure 8E is a cross-sectional view along the line 8E-8E in Figure 8A. As shown in Figures 8A to 8E, the running position adjustment cap 20C includes a cap body 21C. The cap body 21C adjusts the running position of the curved belt 13 by supporting the roller shaft 16 at a position where it has been moved in the vertical direction C of the curved belt 13. The cap body 21C has a side wall portion 22C and a roller shaft insertion portion 23C into which the roller shaft 16 can be inserted. Components that are the same as those in the above embodiment, the first modified example and the second modified example are denoted by the same reference numerals and their detailed descriptions are omitted.

[0072] The side wall portion 22C is formed in a cylindrical shape. In this example, the side wall portion 22C is formed in a bottomed cylindrical shape with one end closed in the axial direction of the side wall portion 22C and the other end open. The outer surface (end face) of one end of the side wall portion 22C is composed of a curved portion. A flange portion 26 is provided at the other end of the side wall portion 22C. When viewed from the front, the shape of the side wall portion 22C is oval in Figure 8A. The outer circumferential surface of the side wall portion 22C is composed of a pair of flat portions and a pair of curved portions connecting the pair of flat portions. The shape of the side wall portion 22C when viewed from the front is not limited to oval, but may be circular, elliptical, polygonal, etc. When viewed from the front, the shape of the flange portion 26 is a square with two adjacent corners being right angles and two opposite corners being rounded by arcs.

[0073] The side wall portion 22C has a thin-walled portion 34 in which the thickness of a part of the circumferential direction of the side wall portion 22C is thinner than the thickness of other parts. In this example, the thin-walled portion 34 is provided on one of the pair of curved portions that constitute the outer circumferential surface of the side wall portion 22C. The thin-walled portion 34 is not limited to being provided on one curved portion side of the side wall portion 22C, but may also be provided on the other curved portion side.

[0074] The roller shaft insertion portion 23C is formed in a cylindrical shape. The roller shaft insertion portion 23C is constituted by the inner peripheral surface of the side wall portion 22C, and communicates with an opening at the other end of the side wall portion 22C. The center position of the roller shaft insertion portion 23C is shifted from the center position of the side wall portion 22C. More specifically, the center position of the roller shaft insertion portion 23C is shifted from the center position of the side wall portion 22C toward the thin-walled portion 34. When the travel position adjustment cap 20C is attached to the outer frame 14 and the inner frame 15, the thin-walled portion 34 is oriented in the vertical direction C of the curved belt 13. That is, the roller shaft insertion portion 23C is provided at a position offset in the vertical direction C with respect to the center position of the side wall portion 22C. The shape of the roller shaft insertion portion 23C when viewed from the back surface is a hexagon in FIG. 8B, but is not limited thereto, and may be a polygon other than a hexagon, a circle, an ellipse, an oval, or the like.

[0075] A distance X between a central axis O1 of the side wall portion 22C and a central axis O2 of the roller shaft insertion portion 23C is represented by the above formula (1). In this example, the distance X is 2.5 mm, but is not limited thereto. In the third modification, the radial direction of the side wall portion 22C and the radial direction of the roller shaft insertion portion 23C are directions along the vertical direction C of the curved belt 13. A length L1 of the side wall portion 22C in the radial direction (see FIGS. 8A and 8E) and a length L2 of the roller shaft insertion portion 23C in the radial direction (see FIGS. 8B and 8E) satisfy a relationship of L1 > L2.

[0076] As shown in FIG. 8E, when W1 is a thickness of the thin-walled portion 34 of the side wall portion 22C, and W2 is a thickness of the wall portion 25 opposite to the thin-walled portion 34 across the central axis O1 of the side wall portion 22C, in the side wall portion 22C, the thickness W1 of the thin-walled portion 34 is smaller than the thickness W2 of the wall portion 25 opposite to the thin-walled portion 34 across the central axis O1 of the side wall portion 22C. That is, in the side wall portion 22C, the thickness W1 of the thin-walled portion 34 and the thickness W2 of the wall portion 25 opposite to the thin-walled portion 34 across the central axis O1 of the side wall portion 22C satisfy a relationship of W1 < W2. In this example, the thickness W1 of the thin-walled portion 34 is 1.7 mm, and the thickness W2 of the wall portion 25 opposite to the thin-walled portion 34 is 6.7 mm.

[0077] Figure 9 is an explanatory diagram illustrating how the running position adjustment cap 20C is attached to the roller 12a. In Figure 9, the front of the paper is the loosening direction A, and the back of the paper is the tensioning direction B. Figure 9 shows the side view (right side) of the running position adjustment cap 20C and the roller 12a as seen in the tensioning direction B, as well as the cross-section of the curved belt 13 and the outer frame 14. This explanation describes the case where the running position adjustment cap 20C is attached to the roller 12a (tail roller), but the same applies when the running position adjustment cap 20C is attached to the roller 12e (head roller).

[0078] When attaching the running position adjustment cap 20C to the roller 12a, the thin-walled portion 34 of the side wall portion 22C is oriented in the vertical direction C. That is, the side wall portion 22C has a thin-walled portion 34 provided on the vertical direction C side of the side wall portion 22C.

[0079] As shown in Figure 9, when the cap body 21C is attached to the outer frame 14, the thin-walled portion 34 of the side wall 22C is oriented upward in the vertical direction C. By oriented upward when the cap body 21C is attached to the outer frame 14, the movement of the curved belt 13 toward the inner circumference can be more effectively suppressed. In Figure 9, the upward direction in the vertical direction C is indicated by a white arrow. Although not shown, when the cap body 21C is attached to the inner frame 15, the thin-walled portion 34 of the side wall 22C is oriented downward in the vertical direction C. By oriented downward when the cap body 21C is attached to the inner frame 15, the movement of the curved belt 13 toward the inner circumference can be more effectively suppressed.

[0080] The roller shaft 16 of the roller 12a is inserted into the roller shaft insertion portion 23C. The side wall portion 22C is inserted into and fitted into the hole 14a of the outer frame 14. In this example, the shape of the side wall portion 22C and the shape of the hole 14a of the outer frame 14 are designed to be oval-shaped so that the side wall portion 22C can be press-fitted into the hole of the outer frame 14 and fixed in place. By bringing the flange portion 26 provided at the other end of the side wall portion 22C into contact with the inner circumferential surface of the outer frame 14, the roller shaft 16 of the roller 12a can be attached to the outer frame 14 via the running position adjustment cap 20C.

[0081] The third modified travel position adjustment cap 20C is attached to the outer frame 14 and the inner frame 15 and includes a cap body 21C that rotatably supports a pair of rollers 12a and 12e (tail roller and head roller) located at both ends of a plurality of rollers 12a to 12e. The cap body 21C adjusts the travel position of the curved belt 13 by supporting both roller shafts 16 of the pair of rollers 12a and 12e in a position moved in the vertical direction C of the curved belt 13. By including the cap body 21C, the travel position adjustment cap 20C can effectively suppress movement of the curved belt 13 toward the inner circumference, preventing meandering and uneven travel of the curved belt 13. Therefore, the travel position adjustment cap 20C and the curved conveyor equipped therewith can easily improve the travel stability of the curved belt 13 without changing the configuration of the outer frame 14 and the inner frame 15, similar to the above embodiment. Furthermore, the travel stability of the curved belt 13 can be improved regardless of the type of roller conveyor, the size of the curved belt 13, or external environmental factors.

[0082] The running position adjustment cap 20C is configured to be easily attached to and detached from a pair of rollers 12a and 12e. The running position adjustment cap 20C and the curved conveyor equipped with it allow for easy changes in the position of the roller shaft 16 by replacing or changing the orientation of the running position adjustment cap 20C, thereby easily improving the running stability of the curved belt 13.

[0083] The running position adjustment cap 20C may have an opening 24 that opens up a part of the circumferential direction of the side wall portion 22C instead of the thin-walled portion 34. The opening 24 in the side wall portion 22C exposes the roller shaft 16 inserted into the roller shaft insertion portion 23C. That is, the side wall portion 22C has an opening 24 that exposes the roller shaft 16 inserted into the roller shaft insertion portion 23C on the vertical direction C side of the side wall portion 22C. When the running position adjustment cap 20C having the opening 24 is attached to the outer frame 14 or inner frame 15, the opening 24 is oriented in the vertical direction C of the side wall portion 22C. Since the roller shaft 16 exposed from the opening 24 in the side wall portion 22C directly contacts the outer frame 14 or inner frame 15, rattle and distortion are suppressed.

[0084] 3. Curved belt running position evaluation test In a curved conveyor 10 equipped with the travel position adjustment cap 20 according to the above embodiment, a test was conducted to evaluate the travel position of the curved belt 13 (referred to as the curved belt travel position evaluation test). As described above, the travel position adjustment cap 20 is attached to at least one of the outer frame 14 and the inner frame 15 and includes a cap body 21 that rotatably supports at least one of a pair of rollers 12a and 12e (tail roller and head roller). The cap body 21 supports the roller shaft 16 of at least one of the pair of rollers 12a and 12e in a position moved toward the slackening direction of the curved belt 13. The travel position adjustment cap 20 is configured such that the center position of the roller shaft insertion portion 23 is moved 1.2 mm toward the opening 24 side from the center position of the side wall portion 22.

[0085] When the running position adjustment cap 20 is attached to only one location on the outer circumference end of the roller shaft 16 of roller 12e, when the running position adjustment cap 20 is attached to only one location on the outer circumference end of the roller shaft 16 of roller 12a, when the running position adjustment cap 20 is attached to only one location on the inner circumference end of the roller shaft 16 of roller 12e, when the running position adjustment cap 20 is attached to only one location on the inner circumference end of the roller shaft 16 of roller 12a, when the running position adjustment cap 20 is attached to a total of two locations on the outer circumference ends of the roller shafts 16 of roller 12a and roller 12e, and a total of three locations on the outer circumference ends of the roller shaft 16 of roller 12e and the inner circumference end of the roller shaft 16 of roller 12e. In each of the following cases, the direction in which the opening 24 with the side wall 22 faces the slack direction A of the curved belt 13: when the running position adjustment caps 20 are attached to a total of four locations, including the inner and outer ends of the roller shafts 16 of each of the rollers 12a and 12e; when the running position adjustment caps 20 are attached to a total of two locations, including the inner and outer ends of the roller shaft 16 of the roller 12e; and when the running position adjustment caps 20 are attached to a total of two locations, including the inner and outer ends of the roller shaft 16 of the roller 12a. In the curved belt running position evaluation test, the curved belt 13 was run, and the position of the outer edge of the curved belt 13 was measured and designated as the measurement position. Then, the running position of the curved belt 13 was evaluated based on the reference position and the measurement position.

[0086] Figure 10 is an explanatory diagram illustrating the results of a curve belt running position evaluation test using the running position adjustment cap 20 according to the embodiment.

[0087] In Figure 10, the results when the running position adjustment cap 20 is attached to only one location on the outer circumference end of the roller shaft 16 of roller 12e are shown as (1), the results when the running position adjustment cap 20 is attached to only one location on the outer circumference end of the roller shaft 16 of roller 12a are shown as (2), the results when the running position adjustment cap 20 is attached to only one location on the inner circumference end of the roller shaft 16 of roller 12e are shown as (3), the results when the running position adjustment cap 20 is attached to only one location on the inner circumference end of the roller shaft 16 of roller 12a are shown as (4), the results when the running position adjustment cap 20 is attached to a total of two locations on the outer circumference ends of the roller shafts 16 of roller 12a and roller 12e are shown as (5), and the outer circumference ends of the roller shafts 16 of roller 12a and roller 12e are shown as (1) The results when the running position adjustment caps 20 were attached to a total of three locations, including the inner circumference end of the roller shaft 16 of roller 12e, are shown as (6). The results when the running position adjustment caps 20 were attached to a total of four locations, including the inner circumference end and outer circumference end of each roller shaft 16 of roller 12a and roller 12e, are shown as (7). The results when the running position adjustment caps 20 were attached to a total of two locations, including the inner circumference end of each roller shaft 16 of roller 12a and roller 12e, are shown as (8). The results when the running position adjustment caps 20 were attached to a total of two locations, including the inner circumference end and outer circumference end of the roller shaft 16 of roller 12e, are shown as (9). The results when the running position adjustment caps 20 were attached to a total of two locations, including the inner circumference end and outer circumference end of the roller shaft 16 of roller 12a, are shown as (10). "Belt running position (mm)" indicates the amount of change at each measurement position relative to the reference position. The position of the outer end of the curved belt 13 is positive (+) if it moves toward the inner circumference, and negative (-) if it moves toward the outer circumference.

[0088] In all results from (1) to (10), the position of the outer end of the curved belt 13 moved toward the outer circumference. From these results, it was confirmed that by simply attaching the running position adjustment cap 20 to at least one of the outer frame 14 and the inner frame 15, the movement of the curved belt 13 toward the inner circumference can be effectively suppressed without changing the configuration of the outer frame 14 and the inner frame 15, and the running stability of the curved belt 13 can be easily improved.

[0089] In (7), where the running position adjustment caps 20 were attached in four locations, the amount of change in the measured position relative to the reference position was greater than in (1) to (6) and (8) to (10), where the running position adjustment caps 20 were attached in one to three locations. In (6), where the running position adjustment caps 20 were attached in three locations, the amount of change in the measured position relative to the reference position was greater than in (1) to (5) and (8) to (10), where the running position adjustment caps 20 were attached in one or two locations. In (5) and (8) to (10), where the running position adjustment caps 20 were attached in two locations, the amount of change in the measured position relative to the reference position was greater than in (1) to (4), where the running position adjustment cap 20 was attached in one location. From the above, it was confirmed that the more running position adjustment caps 20 that are attached, the greater the amount of change in the measured position relative to the reference position, and the greater the effect of improving the running stability of the curve belt 13.

[0090] Comparing (5), (8) to (10), in which the running position adjustment caps 20 are attached in two locations, (9) and (10), in which the running position adjustment caps 20 are attached to both the inner and outer ends of the roller shaft 16, the amount of change in the measured position relative to the reference position is greater than in (5), in which the running position adjustment cap 20 is attached to the outer end of the roller shaft 16, and in (8), in which the running position adjustment cap 20 is attached to the inner end of the roller shaft 16. From the above, it was confirmed that attaching the running position adjustment caps 20 to both the inner and outer ends of the roller shaft 16 tends to improve the running stability of the curved belt 13 more effectively than attaching the running position adjustment caps 20 to either the inner or outer end of the roller shaft 16. Furthermore, comparing the case where the running position adjustment cap 20 is attached to the outer circumference end of the roller shaft 16 (5) with the case where the running position adjustment cap 20 is attached to the inner circumference end of the roller shaft 16 (8), it was confirmed that attaching the running position adjustment cap 20 to the outer circumference end of the roller shaft 16 tends to improve the running stability of the curved belt 13 more effectively than attaching the running position adjustment cap 20 to the inner circumference end of the roller shaft 16.

[0091] The present invention is not limited to the embodiments and modifications described above, and various modifications are possible within the scope of the technical idea described in the claims, specification and drawings. [Explanation of Symbols]

[0092] 10 Curved conveyor 12 Laura 12a Roller (Tail Roller) 12b~12d Roller (Intermediate Roller) 12e Roller (Head Roller) 16 Roller shaft 17 Roller body 17a Roller body (Roller body of the tail roller) 17b~17d Roller body (Roller body of the intermediate roller) 17e Roller body (Roller body of the head roller) 13 Curved belt 18 sleeves 20, 20A, 20B, 20C Driving position adjustment cap 21, 21A, 21B, 21C Cap Body 22, 22A, 22B, 22C side wall 23, 23A, 23B, 23C Roller shaft insertion section 24 openings 34 Thin-walled section

Claims

1. Outer frame and inner frame with an arc shape in plan view, Multiple rollers arranged radially in a plan view and rotatably supported by the outer frame and the inner frame, A curved belt is wrapped around each of the pair of rollers located at both ends of the aforementioned plurality of rollers, and travels in an arc shape when viewed from above. A travel position adjustment cap used in a curved conveyor equipped with, The cap body is attached to at least one of the outer frame and the inner frame and rotatably supports at least one of the pair of rollers, The cap body is a running position adjustment cap that adjusts the running position of the curved belt by supporting at least one roller shaft of the pair of rollers in a position where the curved belt is moved in the slackening direction and / or vertical direction.

2. The cap body has a side wall portion and a roller shaft insertion portion configured to allow the roller shaft to be inserted, The running position adjustment cap according to claim 1, wherein the roller shaft insertion portion is provided at a position offset in the loosening direction and / or the vertical direction with respect to the center position of the side wall portion.

3. The running position adjustment cap according to claim 2, wherein the side wall portion has an opening on the side of the side wall portion that exposes the roller shaft inserted into the roller shaft insertion portion, on the side of the side wall portion that is loosening direction and / or the side that is vertical.

4. The travel position adjustment cap according to claim 2, wherein the side wall portion has a thin-walled portion provided on the side of the side wall portion in the loosening direction and / or the vertical direction.

5. Outer frame and inner frame with an arc shape in plan view, Multiple rollers arranged radially in a planar view, A curved belt is wrapped around each of the pair of rollers located at both ends of the plurality of rollers, and travels in an arc shape when viewed from above, A plurality of shaft caps attached to the outer frame and the inner frame, which rotatably support the pair of rollers, Equipped with, A curved conveyor in which at least one of the plurality of shaft core caps is a travel position adjustment cap according to any one of claims 1 to 4.

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