Roller Screen

Abstract

To easily replace rollers in a roller screen.SOLUTION: Provided is a roller screen comprising a plurality of rollers 1 arranged in parallel, and a first support device 40 that supports one ends of the rollers 1 in an axial direction with a frame 6 and a second support device 50 that supports the other ends in the axial direction with the frame 6. In the roller screen, the roller 1 comprises a hollow cylindrical body 1b; the first support device 40 comprises a first support shaft 41 to be fixed to one end of the cylindrical body 1b in the axial direction via a first bolt 44 and a first bearing part 45 to be fixed to the frame 6 via a second bolt 46; the second support device 50 comprises a second support shaft 51 to be fixed to the other end of the cylindrical body 1b in the axial direction via a third bolt 54 and a second bearing part 55 that rotatably supports the second support shaft 51 with the frame 6; and the first support shaft 41 and the first bearing part 45 can be separated from the cylindrical body 1b and the frame 6 in a state of removing the first bolt 44 and the second bolt 46.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] This invention relates to a roller screen.

Background Art

[0002] Conventionally, roller screens have been used to classify materials to be processed, such as earth and sand, crushed stones, ores, cokes, and other various lumps and granular materials. A roller screen includes a plurality of rollers that rotate by a driving force, arranged in parallel at a predetermined interval. The material to be processed moves along the rotation direction of the rollers on the rollers. Materials to be processed smaller than the interval set between the rollers are screened out between the rollers, and larger ones pass over the rollers, enabling screening according to the particle size.

[0003] The rollers used in roller screens are worn on their surfaces by contact with the material to be processed. Therefore, when the wear of the rollers reaches the limit value affecting the screening performance, the rollers need to be replaced. Since rollers are usually made of materials with high wear resistance, frequent roller replacement is costly. Thus, for example, in Patent Document 1, a roller is configured by dividing it into a roll core and a cylindrical body made of a wear-resistant material fitted around the outer periphery of the roll core. By limiting the expensive wear-resistant material only to the cylindrical body that contacts the material to be processed, the cost of the roller is reduced. In addition, in Patent Document 2, a roller is made into a hollow cylindrical body, and by making the support shafts inserted at both axial ends of the hollow roller detachable, a technique is disclosed that enables the replacement of the roller without removing the sprocket and chain, which are the driving means of the roller, from the apparatus main body.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

[0005] In the roller screen described in Patent Document 1, support shafts are integrally provided at both axial ends of the roller core. Therefore, when replacing the roller, it is necessary to detach or remove the sprocket and chain fixed to the support shaft, remove the roller core together with the cylindrical body from the device body, and then separate the cylindrical body from the roller core. Furthermore, the reverse process is required when attaching a new roller to the device body. Such work is time-consuming and laborious, and is particularly cumbersome due to the weight of the roller core. In addition, in the roller screen described in Patent Document 2, the separation of the roller and support shaft must be performed with the roller and support shaft removed from the device body. Moreover, the roller cannot be removed from the device body unless the sprocket and chain fixed to the roller's support shaft are detached from the support shaft. Therefore, Patent Document 2 is similar to Patent Document 1 in that the work is cumbersome.

[0006] Therefore, the objective of this invention is to facilitate the replacement of the rollers in a roller screen. [Means for solving the problem]

[0007] To solve the above problems, this invention provides a roller screen comprising a plurality of parallel rollers, a first support device that supports one axial end of the rollers on a frame and a second support device that supports the other axial end of the rollers on the frame, and a drive source for rotating the rollers, wherein the rollers are made of hollow cylindrical bodies, the first support device comprises a first support shaft fixed to one axial end of the cylindrical body via a first bolt and a first bearing portion fixed to the frame via a second bolt and rotatably supporting the first support shaft on the frame, the second support device comprises a second support shaft fixed to the other axial end of the cylindrical body via a third bolt and a second bearing portion rotatably supporting the second support shaft on the frame, and the first support shaft and the first bearing portion are detachable from the cylindrical body and the frame when the first bolt and the second bolt are removed.

[0008] Here, a rotation transmission member is attached to the second support shaft of another roller adjacent to the second support shaft, and the cylindrical body can be configured to be detachable from the second support shaft and the frame when the third bolt is removed.

[0009] Furthermore, the first bolt and the third bolt can be screwed into the cylindrical body on the axial side of the axial width of the workpiece to be processed on the cylindrical body.

[0010] In each of these embodiments, an input member is provided at one axial end of at least one of the parallel rollers to which the driving force from the drive source is input, and the input member can be detached from the cylindrical body and the frame together with the first support shaft and the first bearing portion.

[0011] To solve the above problems, this invention provides a method for replacing rollers in a roller screen comprising a plurality of parallel rollers, a first support device that supports one axial end of the rollers on a frame and a second support device that supports the other axial end of the rollers on the frame, and a drive source for rotating the rollers, wherein the rollers comprise a hollow cylindrical body, the first support device comprises a first support shaft fixed to one axial end of the cylindrical body via a first bolt and a first bearing portion fixed to the frame via a second bolt and rotatably supporting the first support shaft on the frame, the second support device comprises a second support shaft fixed to the other axial end of the cylindrical body via a third bolt and a second bearing portion rotatably supporting the second support shaft on the frame, and the method for replacing rollers includes the steps of removing the first bolt and the second bolt and detaching the first support shaft and the first bearing portion from the cylindrical body and the frame. [Effects of the Invention]

[0012] This invention makes it possible to easily replace the rollers of a roller screen. [Brief explanation of the drawing]

[0013] [Figure 1] Plan view showing one embodiment of this invention [Figure 2] Longitudinal cross-sectional view of the same embodiment [Figure 3] Right side view of Figure 1 [Figure 4] Disassembled, enlarged cross-sectional view of the roller area. [Figure 5A] Longitudinal cross-section of the roller [Figure 5B] (a) is a plan view of the roller, and (b) is a cross-sectional view of (a). [Figure 5C] (a) is a front view of the roller, and (b) is a cross-sectional view of (a). [Figure 6] Exploded view of the area near the first support device [Figure 7] Enlarged longitudinal section view of the main part of the roller [Modes for carrying out the invention]

[0014] Embodiments of this invention will be described based on the drawings. This embodiment uses construction waste and aggregates (crushed stones) as the object to be processed C, a roller screen R used for classifying the object to be processed C, and a method for replacing the roller 1 in the roller screen R. The configuration of a roller screen unit S equipped with the roller screen R is shown in FIGS. 1 and 2.

[0015] The roller screen R includes a plurality of rollers 1 arranged in parallel and rotated by a driving force from a driving source 5. The frame 6 that supports the roller 1 is supported by a base frame 8 placed on the ground G. One end of the frame 6 is vertically movable by a lifting device 7, and the other end is rotatable by a fulcrum support portion 9 connected by a hinge. The lifting device 7 has a rod that expands and contracts by the operation of hydraulic pressure connected to one end of the frame 6. When the rod extends, one end of the frame 6 rises, and the elevation angle α of the roller screen R with respect to the horizontal direction increases. When the rod contracts, the elevation angle α decreases. That is, the frame 6 that supports the roller 1 can be raised and lowered by the lifting device 7. If the base frame 8 is mounted on a traveling device, the device can be moved to any location.

[0016] The plurality of rollers 1 arranged in parallel are each rotated in the same direction around the axis by a driving force supplied from the driving source 5. The driving source 5 in this embodiment is a motor 5a. As shown in FIGS. 1 and 3, the rotation of the motor 5a is transmitted to the support shaft of the roller 1 through an input member 5b composed of a pulley and a belt or the like. The rotation transmitted to the support shaft of one roller 1 is transmitted to the support shaft of the adjacent other roller 1 through a rotation transmission member 5c provided on the opposite side of the input member 5b across the roller 1. Also, the rotation of the other roller 1 to which the driving force is transmitted is further transmitted to the support shaft of another roller 1 through the rotation transmission member 5c. As the rotation transmission member 5c, a sprocket attached to the support shaft and a chain wound between the sprockets are adopted. The configurations of the input member 5b and the rotation transmission member 5c are not limited to the above, and other means may be adopted.

[0017] A predetermined gap (spacing) is set between adjacent rollers 1,1. This gap is called the roller gap w. As shown in Figure 7, the roller gap w is the shortest distance between the closest points of the outer circumferences 1a of adjacent rollers 1,1. The roller gap w can be adjusted to any dimension. This adjustment can be done by moving the fixing point of the support shaft to the frame 6 along the parallel direction of the rollers 1. As a fixing structure between the support shaft of the roller 1 and the frame 6, for example, holes can be provided intermittently at a predetermined pitch along the longitudinal direction of the frame 6 on both sides in the width direction of the roller, and the roller gap w can be adjusted by inserting both ends of the support shaft of the roller 1 into either pair of holes and fixing the support shaft with a tightening means such as a nut. Alternatively, elongated holes can be provided along the longitudinal direction of the frame 6 on both sides in the width direction of the roller, and the roller gap w can be adjusted by sliding both ends of the support shaft of the roller 1 in the longitudinal direction of the elongated holes and fixing the support shaft with a tightening means such as a nut at any position.

[0018] At one end of the roller 1 in the parallel direction, a loading section 3 for the workpiece C is provided. The loading section 3 is a hopper installed above one end of the frame 6. The workpiece C that has fallen from the loading section 3 moves along the roller 1 in the rotation direction of the roller 1. The workpiece C with a smaller diameter than the roller gap w is sieved downward through the space between the rollers 1, 1, and the workpiece C with a larger diameter than the roller gap w passes over the roller 1 and reaches the other end. Thus, sieving according to the particle size is possible. That is, setting the classification point of the roller screen R to t means that it is desired to guide the workpiece C with an outer diameter of t (mm) or more to the recovery section 4 and the workpiece C with an outer diameter less than the classification point t (mm) to the sieving section 2, respectively. Here, the location where the workpiece C is placed below the roller gap w (below the group of rollers 1) is referred to as the sieving section 2, and the location where the workpiece C is placed at the other end of the roller 1 in the parallel direction is referred to as the recovery section 4. The small-diameter workpiece C that has fallen into the sieving section 2 is guided onto a sieving section transfer device 11 composed of a belt conveyor or the like through the guiding section 2a. The small-diameter workpiece C is carried out to the next process by the sieving section transfer device 11. Also, the large-diameter workpiece C that has fallen into the recovery section 4 is guided onto a recovery section transfer device 12 composed of a belt conveyor or the like through the guiding section 4a. The large-diameter workpiece C is carried out to the next process by the recovery section transfer device 12.

[0019] The roller screen unit S is controlled by the control device 30 so that its functions and overall operations are controlled. Also, the rotation speed of the roller 1 (the number of rotations per unit time (min -1The speed control unit 31 of the control device 30 controls the speed control unit 31. Furthermore, the sieving unit transfer device 11 and the recovery unit transfer device 12 are controlled by the transfer device control unit 33. Other information necessary for the sieving process of the material to be processed C can be input into the setting unit 34. Based on the information input into the setting unit 34, the control device 30 commands the necessary operations. In this embodiment, as shown in Figure 2, the main body of the roller screen R is set so that the parallel direction of the rollers 1 is inclined downwards toward the feeding direction of the material to be processed C. The elevation angle α of this inclination direction with respect to the horizontal direction can be appropriately changed according to the material and particle size distribution of the material to be processed C. This elevation angle α can be adjusted by controlling the lifting device 7 with respect to the angle control unit 32 of the control device 30.

[0020] The fixing structure of the roller 1 to the frame 6, and the method for replacing the roller 1, will be described below.

[0021] As shown in Figures 3 and 4, the roller screen R includes a first support device 40 that supports one axial end of the roller 1 on the frame 6, and a second support device 50 that supports the other axial end of the roller 1 on the frame 6. Here, an H-beam is used as the frame 6. The roller 1 also includes a hollow cylindrical body 1b made of steel pipe for general structural or mechanical structural use, and plate-shaped end face members 1c fixed to both ends of the cylindrical body 1b by welding or the like. By constructing the roller 1 from a cylindrical body 1b, the weight of the components is reduced. Furthermore, by using wear-resistant materials, the frequency of replacement can be reduced.

[0022] As shown in Figure 4, the first support device 40 includes a first support shaft 41 fixed to the cylindrical body 1b via a first bolt 44 that is screwed into a threaded hole 1d formed in the end face member 1c at one end of the cylindrical body 1b, and a first bearing portion 45 fixed to the frame 6 via a second bolt 46 and supporting the first support shaft 41 so that it can rotate around the axis relative to the frame 6.

[0023] The first support shaft 41 is a support shaft that supports one axial end of the roller 1 to the frame 6. In this embodiment, the outer circumference of the first support shaft 41 is provided with a flange 42 having a flange-like shape. The flange 42 is formed by machining, welding, etc. The first bolt 44 is inserted through a hole 43 formed in the flange 42, and its tip is screwed into a threaded hole 1d. The tip of the first support shaft 41 is fitted into a central hole 1e formed in the end face member 1c, and by tightening the first bolt 44, the end face member 1c and the flange 42 are in close contact in a surface state, thereby firmly fixing the cylindrical body 1b and the first support shaft 41. That is, the first support shaft 41 is detachable from the cylindrical body 1b by tightening and loosening the first bolt 44. The first bearing portion 45 is equipped with a rolling bearing inside the casing and has a flange portion 45b that protrudes outward along the outer edge of the casing. The second bolt 46 is inserted through a hole 45a formed in the flange portion 45b, a hole 47a formed in the reinforcing piece 47 fixed to the frame 6 by welding or the like, and a hole 6a formed in the frame 6, and a nut 48 is tightened to its tip. By tightening the second bolt 46 and nut 48, the first support shaft 41 is fixed to the frame 6 together with the first bearing portion 45. In other words, the first bearing portion 45 can be attached to and detached from the frame 6 by tightening and loosening the second bolt 46 and nut 48. Reference numeral 49 in the figure indicates a sealing device.

[0024] As shown in Figure 4, the second support device 50 includes a second support shaft 51 fixed to the cylindrical body 1b via a third bolt 54 that is screwed into a threaded hole 1d formed in the end face member 1c at the other end of the cylindrical body 1b, and a second bearing portion 55 fixed to the frame 6 via a fourth bolt 56 and supporting the second support shaft 51 so that it can rotate around the axis relative to the frame 6.

[0025] The second support shaft 51 is a support shaft that supports the other axial end of the roller 1 to the frame 6. In this embodiment, the outer circumference of the second support shaft 51 is provided with a flange 52 having a flange-like shape. The flange is formed by machining, welding, etc. The third bolt 54 is inserted through a hole 53 formed in the flange 52, and its tip is screwed into a threaded hole 1d. The tip of the second support shaft 51 is fitted into a central hole 1e formed in the end face member 1c, and by tightening the third bolt 54, the end face member 1c and the flange 52 are in close contact in a surface state, thereby firmly fixing the cylindrical body 1b and the second support shaft 51. The second support shaft 51 can be attached to and detached from the cylindrical body 1b by tightening and loosening the third bolt 54. The second bearing portion 55 is equipped with a rolling bearing inside the casing and has a flange portion 55b that protrudes outward along the outer edge of the casing. The fourth bolt 56 is inserted through a hole 55a formed in the flange portion 55b, a hole 57a formed in the reinforcing piece 57 fixed to the frame 6 by welding or the like, and a hole 6a formed in the frame 6, and a nut 58 is tightened to its tip. By tightening the fourth bolt 56 and nut 58, the second support shaft 51 is fixed to the frame 6 together with the second bearing portion 55. In other words, the second bearing portion 55 can be attached to and detached from the frame 6 by tightening and loosening the fourth bolt 56 and nut 58. Reference numeral 59 in the figure indicates a sealing device.

[0026] When replacing the roller 1 with the main body of the device, the used roller 1 fixed to the frame 6 is removed from the frame 6, and then the new roller 1 is attached to the frame 6. When removing the roller 1, first the first bolt 44 and the second bolt 46 are loosened and removed. Then, the first support shaft 41 and the first bearing portion 45 are separated from the cylindrical body 1b and the frame 6. By adopting a roller replacement method that includes the steps of removing the first bolt 44 and the second bolt 46 and separating the first support shaft 41 and the first bearing portion 45 from the cylindrical body 1b and the frame 6, the separation of the first bearing portion 45 from the cylindrical body 1b and the frame 6 is made easy. In particular, if the first support shaft 41 and the first bearing portion 45 are removed from the frame 6 as a single unit without being separated, the work when attaching the roller 1 described later is made easier.

[0027] Next, the third bolt 54 is loosened and removed. Then, the cylindrical body 1b is detached from the second support shaft 51 and the frame 6. Since the cylindrical body 1b can be detached from the second support shaft 51 and the frame 6 with the third bolt 54 removed, it is not necessary to remove the second support shaft 51 from the frame 6. In other words, by adopting a roller replacement method that includes the steps of removing the third bolt 54 and detaching the cylindrical body 1b from the second support shaft 51 and the second bearing portion 55, the separation of the cylindrical body 1b from the frame 6 is made easy. Furthermore, since a rotation transmission member 5c that transmits rotation to other adjacent rollers 1 is attached to the second support shaft 51, it is possible to replace the roller 1 without removing the rotation transmission member 5c (sprocket, chain, etc.).

[0028] These first bolts 44 and third bolts 54 are screwed into the cylindrical body 1b on the axial side of the mounting width A (see Figure 3) of the workpiece C on the cylindrical body 1b, thereby preventing obstruction of tightening and loosening of the bolts due to the workpiece C adhering near the screw holes 1d. In this embodiment, the end face member 1c in which the screw holes 1d are formed is located axially outward from the pair of guide plates a, a that determine the mounting width A.

[0029] Of the multiple parallel rollers 1, some (at least one) of the rollers 1 have an input member 5b attached to one end of the first support shaft 41 in the axial direction. Figure 3 shows a roller 1 with an input member 5b, while Figures 4 and 6 show a roller 1 without an input member 5b. When removing a roller 1 with an input member 5b, the input member 5b can be detached from the cylindrical body 1b and frame 6 together with the first support shaft 41 and the first bearing portion 45. If the input member 5b is removed from the frame 6 as a whole without separating it from the first support shaft 41, the work when installing the roller 1 described later will be easier. It is advisable to remove any endless member (belt, etc.) wound around the pulley or the like, which is the input member 5b, beforehand.

[0030] Here, when detaching the first support shaft 41 and the first bearing portion 45 (along with the input member 5b, if present) from the frame 6, it is preferable that a predetermined space (room) is secured on one axial end side of the frame 6, as shown in Figure 6. The space (room) should preferably be a cross-section through which the first bearing portion 45 and the input member 5b can pass. In this way, with the tip of the first support shaft 41 already out of the frame 6, the first support shaft 41 can be easily detached from the main body of the device together with the first bearing portion 45.

[0031] The installation of roller 1 is the reverse of the removal process described above. Specifically, the process involves tightening the third bolt 54 to fix the cylindrical body 1b of the new roller 1 to the second support shaft 51, followed by tightening the first bolt 44 and the second bolt 46 to fix the first support shaft 41 and the first bearing portion 45 to the cylindrical body 1b.

[0032] In this embodiment, as shown in Figures 5B and 5C, the outer circumference 1a of the roller 1 is provided with a projection 20 extending in the axial direction of the roller 1. As shown in Figure 1, the axial range r of the projection 20 of one roller 1 and the axial range r' of the projection 20 of the adjacent roller 1 are set to be at different positions with respect to the axial direction. That is, the axial ranges r and r' of the projections 20 of two adjacent rollers 1 are set so as not to overlap. In this embodiment, the projection 20 is formed by a weld bead, but other structures may be adopted, such as welding a shaft-shaped member. By providing projections 20 on the surface of the roller 1, large chunks of material C stuck between the rollers 1, 1 can be easily dropped downwards. Here, the projections 20 not only push the chunks of material C downwards, but are also expected to crush them with compressive force and further lift the chunks from below to transport them to the downstream roller 1. This eliminates the clogging of material C between the rollers 1, 1. Furthermore, since the protrusions 20 do not overlap in the axial direction of roller 1 on two adjacent rollers, the classification accuracy is not reduced without narrowing the roller gap w.

[0033] Furthermore, in this embodiment, as shown in Figure 7, a scraper 10 is provided below the roller 1, facing the outer circumference 1a of the roller 1. The tip 10a of the scraper 10 may be in sliding contact with the outer circumference 1a of the roller 1, but in this embodiment, a predetermined gap v is set between the tip 10a of the scraper 10 and the outer circumference 1a of the roller 1. By providing the scraper 10, it is possible to remove the material to be processed C, which has a high moisture content and high adhesion, that adheres to the outer circumference 1a of the roller 1. This allows a predetermined roller gap w to be maintained, so as not to reduce the screening accuracy, i.e., the classification accuracy mentioned above. Also, since the scraper 10 is installed below the roller 1, the material scraped off from the outer circumference 1a of the roller 1 can be quickly dropped downwards. The scraper 10 is a plate-shaped member, and as shown in Figure 7, the direction B of the plate surface of the plate-shaped member may be perpendicular to the parallel direction L of the roller 1 (the direction connecting the axes p of the group of rollers 1). Furthermore, when setting a predetermined interval v, the dimension can be determined by the thickness of the deposits allowed on the outer circumference 1a of the roller 1.

[0034] Furthermore, as mentioned above, in the roller screen R of this invention, the rotational speed of the roller 1 can be adjusted by the control of the speed control unit 31. In this embodiment, the rotational speed of the roller 1 can be adjusted steplessly and arbitrarily by inverter control. In addition, the elevation angle α of the roller screen R, that is, the elevation angle α of the frame 6 with respect to the horizontal direction, can be adjusted by controlling the lifting device 7 with the angle control unit 32. This elevation angle α can also be adjusted steplessly. By increasing the rotational speed of the roller 1 (increasing the number of rotations per unit time), jamming of the workpiece C is reduced. Also, by decreasing the elevation angle α of the roller screen R (making the downward slope in the direction of movement of the workpiece C gentler), the sieving point of the workpiece C, that is, the point where sieving is completed, can be moved upstream.

[0035] In addition to construction waste soil or aggregates (crushed stone) used in concrete and other applications, the material C to be processed by the roller screen R can also include, for example, soil, ore, coke or other stone materials, or various other lumpy or granular materials. [Explanation of Symbols]

[0036] 1 Laura 1b Cylindrical body 5. Power source 5b Input component 5c Rotation transmission member 6 frames 40 First support device 41 1st support shaft 44 First bolt 45 1st bearing part 46 Second bolt 50 Second support device 51 2nd support shaft 54 Third bolt 55 2nd bearing part A Placement width C. Items to be processed R Roller Screen S Roller Screen Unit

Claims

1. A roller screen comprising a plurality of rollers (1) arranged in parallel, a first support device (40) for supporting one axial end of each of the rollers (1) on a frame (6), a second support device (50) for supporting the other axial end of each of the rollers (1) on the frame (6), and a drive source (5) for rotating the rollers (1), The roller (1) has a hollow cylindrical body (1b), The first support device (40) includes a first support shaft (41) fixed to one axial end of the cylindrical body (1 b) via a first bolt (44), and a first bearing portion (45) fixed to the frame (6) via a second bolt (46) to rotatably support the first support shaft (41) on the frame (6), The second support device (50) includes a second support shaft (51) fixed to the other axial end of the cylindrical body (1 b) via a third bolt (54), and a second bearing portion (55) that rotatably supports the second support shaft (51) on the frame (6), The roller screen is capable of removing the first support shaft (41) and the first bearing portion (45) from the cylindrical body (1b) and the frame (6) when the first bolt (44) and the second bolt (46) are removed.

2. 2. A roller screen as described in claim 1, wherein a rotation transmission member (5c) is attached to the second support shaft (51) of another roller (1) adjacent to the second support shaft (51), and the cylindrical body (1b) can be detached from the second support shaft (51) and the frame (6) when the third bolt (54) is removed.

3. 3. A roller screen according to claim 1 or 2, wherein the first bolt (44) and the third bolt (54) are screwed into the cylindrical body (1b) axially outside the axial placement width (A) of the workpiece on the cylindrical body (1b).

4. 4. A roller screen as described in any one of claims 1 to 3, wherein an input member (5b) to which a driving force from the driving source (5) is input is provided at one axial end of at least one of the plurality of parallel rollers (1), and the input member (5b) is detachable from the cylindrical body (1b) and the frame (6) together with the first support shaft (41) and the first bearing portion (45).

5. A method for replacing rollers (1) in a roller screen comprising: a plurality of rollers (1) arranged in parallel; a first support device (40) for supporting one axial end of each of the rollers (1) on a frame (6); a second support device (50) for supporting the other axial end of each of the rollers (1) on the frame (6); and a drive source (5) for rotating the rollers (1), The roller (1) has a hollow cylindrical body (1b), The first support device (40) includes a first support shaft (41) fixed to one axial end of the cylindrical body (1 b) via a first bolt (44), and a first bearing portion (45) fixed to the frame (6) via a second bolt (46) to rotatably support the first support shaft (41) on the frame (6), The second support device (50) includes a second support shaft (51) fixed to the other axial end of the cylindrical body (1 b) via a third bolt (54), and a second bearing portion (55) that rotatably supports the second support shaft (51) on the frame (6), A roller replacement method including the steps of removing the first bolt (44) and the second bolt (46), and detaching the first support shaft (41) and the first bearing portion (45) from the cylindrical body (1b) and the frame (6).

Images