Abstract:
In order to provide a band-like apparatus cleaning device for removing foreign materials and cleaning a band-like apparatus before the foreign materials become huge on the surface of the band-like apparatus without scattering the foreign materials around by improving a cleaning structure such as the shape of an aperture for shower and the like for the band-like apparatus, there is provided a cleaning device of a band-like apparatus, comprising a hollow rotating roll being supported so as to be capable of turning along the traveling direction of the band-like apparatus and having a plurality of apertures for shower formed in it, and cleaning fluid jetting nozzles arranged at the inner side of the plurality of apertures for shower within an embracing angle of the band-like apparatus wound partially round the rotating roll, the cleaning device cleaning the band-like apparatus by jetting a cleaning fluid to the band-like apparatus from the cleaning fluid jetting nozzles, wherein the cleaning device comprises a plurality of blade plates being adjacent in parallel with the roll axis of the rotating roll in the traveling direction of the band-like apparatus and provides the plurality of blade plates and the rotating roll so as to be capable of freely reciprocating in the roll axis direction.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Technical Field  
         [0002]     The present invention relates to a cleaning device of band-like apparatus for a paper machine being a paper manufacturing appliance, the band-like apparatus being used in a wire part, a press part and a dry part in a paper making stroke.  
         [0003]     2. Background Art  
         [0004]     In general a paper manufacturing appliance, for example, a paper machine pours a pulp suspension being a raw material onto a wire belt and thereby performs a dehydrating process, transfers a sheet-shaped pulp fiber obtained by the dehydrating process onto a press belt in a press part, removes water contained in the pulp fiber through a pressing process and thereby produces a wet paper web. And in a dry part, it transfers the wet paper web obtained in the press part onto a canvas belt and further evaporates moisture therein.  
         [0005]     In such a paper making stroke, foreign materials are stuck on the surface of a band-like apparatus such as a wire belt, a press belt, a canvas belt and the like, namely, on the surface of a band-like cleaning object, and these foreign materials are generally natural resin or gum material extricated from wood, pulp, paper and the like, and further non-water-soluble adhesive materials having such organic matter as additive chemicals and the like used in a paper making stroke as the main ingredient. And these foreign materials are minute adhesive materials being present on a wet paper web in a dry part for example, and are made viscous by heating and stuck on the surface of a canvas belt or a roll.  
         [0006]     As a result, these adhesive materials receive pressure of paper, a dryer roll and the like from the surface of the canvas, come into and deposit in the inside of the canvas, and cause the degree of ventilation of the canvas to decrease. And the adhesive materials which have expanded and grown on the surface of the canvas adhere again or fall from the roll to the canvas and from the canvas to paper. As the result, there has been problems that stains or dents produced on the surface of the canvas cause breaking or defects of paper and cause the degradation in quality or productivity due to troubles such as deterioration in quality or in productivity caused by breaking of paper and the like.  
         [0007]     Thereupon, as disclosed in Japanese Patent Laid-Open Publication No. 5-504604 for example, there has been disclosed a method of providing an air blowing-off nozzle and a water jet device along a wire belt, blowing off an air flow against a band-like cleaning object from the nozzle, feeding water from the water jet device and thereby forming a water film on the inner face of wire, blowing away and sucking foreign materials through taking them in water by the air flow blown off from the air blowing-off nozzle, collecting the foreign materials in a hood and thus cleaning the wire belt.  
         [0008]     However, an air blowing-off nozzle needs to be arranged at a distance from the surface of a band-like cleaning object so as not to touch and damage the band-like cleaning object, and since a high-pressure cleaning fluid jetted from a water jet device exerts a large pressure on the band-like cleaning object, the water jet device and the cleaning object have needed to be arranged at a more distance from each other.  
         [0009]     As a result, a cleaning object and a device such as a nozzle or the like cannot be made close to each other, and in order to secure a certain cleaning capability the jet pressure to the cleaning object must be made high, and therefore the capability of the jet device has needed to be increased by increasing the jet pressure and the like. Due to this, the band-like cleaning object is liable to be damaged by a large jet pressure exerted on the band-like cleaning object, and since the band-like cleaning object needs to be more frequently replaced and the amount of cleaning fluid (air, water and the like) used is increased, there has been a problem that such a method leads to the increase in manufacturing cost and in running cost.  
         [0010]     Therefore, the present inventor has proposed a cleaning device arranging a cleaning fluid jetting nozzle inside a hollow rotating roll and cleaning a band-like cleaning object through an aperture for shower formed in the rotating roll from the jet nozzle. However, this cleaning device has only provided a plurality of apertures for shower at a certain pitches in the roll axis direction of the rotating roll along the roll rotating direction, but has not been made to completely clean away dirt such as foreign materials and the like from the band-like cleaning object by effectively utilizing the shape of an aperture for shower, a rotating roll and the like. As a result, it has been unsatisfactory from the viewpoint of the degree of cleaning of a band-like cleaning object.  
         [0011]     Thereupon, an object of the invention is to provide a cleaning device of a band-like apparatus, being made so as to clean away foreign materials before the foreign materials become huge on the surface of a band-like cleaning object without scattering the foreign materials around by improving a cleaning structure such as the shape of an aperture for shower and the like for the band-like cleaning object, in consideration of the above-described points.  
       DISCLOSURE OF THE INVENTION  
       [0012]     In order to achieve the above-described object, the present invention is attained by a cleaning device of a band-like apparatus, comprising a hollow rotating roll being supported so as to be capable of turning along the traveling direction of the band-like apparatus and having a plurality of apertures for shower formed in it, and cleaning fluid jetting nozzles arranged at the inner side of the plurality of apertures for shower within an embracing angle of the band-like apparatus wound partially round the rotating roll, the cleaning device cleaning the band-like apparatus by jetting a cleaning fluid to the band-like apparatus from the cleaning fluid jetting nozzles, wherein the cleaning device comprises a plurality of blade plates being adjacent in parallel with the roll axis of the rotating roll in the traveling direction of the band-like apparatus and provides the plurality of blade plates and the rotating roll so as to be capable of freely reciprocating in the roll axis direction.  
         [0013]     And the above object is effectively attained by arranging a plurality of blade plates in parallel with the roll axis of the rotating roll and forming a plurality of projected portions and depressed portions at specified pitches at the contact side with the band-like apparatus in each of the blade plates.  
         [0014]     And the above object is effectively attained by forming projected and depressed portions at the contact side with the band-like apparatus in each blade plate.  
         [0015]     And the above object is effectively attained by using three blade plates and forming projected and depressed portions at blade projection pitches of 20 to 40 mm.  
         [0016]     And the above object is effectively attained by forming apertures for shower out of a plurality of long and narrow opening holes formed in the rotating roll and providing a plurality of slits formed so as to intersect the opening holes.  
         [0017]     And the above object is effectively attained by arranging three parallel slits in an inclined direction relative to the longitudinal direction of the apertures for shower as a plurality of slits.  
         [0018]     And the above object is effectively attained by making a plurality of slits cross one another in the shape of X relative to the longitudinal direction of the apertures for shower.  
         [0019]     And the above object is effectively attained by forming a band-like apparatus out of a roll for felt in a press part of a paper making stroke and setting the width of a slit in a range of 8 to 12 mm.  
         [0020]     Further, the above object is effectively attained by forming the band-like apparatus out of a roll for canvas in a dry part of a paper making stroke and setting the width of a slit in a range of 20 to 22 mm. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0021]      FIG. 1 (A) is a schematic perspective view of a cleaning device of a band-like apparatus according to the present invention.  
         [0022]      FIG. 1 (B) is a sectional view taken along line X-X of FIG.  1 (A).  
         [0023]      FIG. 2  is a partially sectional view taken along the axial direction of a cleaning device of a band-like apparatus from which cleaning device a blade device is removed.  
         [0024]      FIG. 3  is a figure showing a plurality of apertures for shower formed in the surface of a rotating roll.  
         [0025]      FIG. 4  is a sectional view taken along line Y-Y of  FIG. 3 .  
         [0026]      FIG. 5  is a graph showing the relation between the slit width of an aperture for shower and the degrees of cleaning and wear in a rotating roll for press of S 300 .  
         [0027]      FIG. 6  is a graph showing the relation between the slit width of an aperture for shower and the degrees of cleaning and wear in a rotating roll for press of S 400 .  
         [0028]      FIG. 7  is a graph showing the relation between the slit width of an aperture for shower and the degrees of cleaning and wear in a rotating roll for press of S 500 .  
         [0029]      FIG. 8  is a graph showing the relation between the slit width of an aperture for shower and the degrees of cleaning and wear in a rotating roll for press of S 600 .  
         [0030]      FIG. 9  is a graph showing the relation between the slit width of an aperture for shower and the degree of cleaning in a rotating roll for canvas of S 300 .  
         [0031]      FIG. 10  is a graph showing the relation between the slit width of an aperture for shower and the degree of cleaning in a rotating roll for canvas of S 400 .  
         [0032]      FIG. 11  is a graph showing the relation between the slit width of an aperture for shower and the degree of cleaning in a rotating roll for canvas of S 500 .  
         [0033]      FIG. 12  is a graph showing the relation between the slit width of an aperture for shower and the degree of cleaning in a rotating roll for canvas of S 600 .  
         [0034]      FIG. 13  is a graph showing the relation between the shape of a slit and the degree of cleaning.  
         [0035]      FIG. 14  is a figure showing the shape of a blade plate according to the invention.  
         [0036]      FIG. 15  is a front view of a blade plate being a variation example of the invention.  
         [0037]      FIG. 16  is a partial plan view of a rotating roll being a variation example of the invention.  
         [0038]      FIG. 17  is a partial plan view of a rotating roll being a variation example of the invention.  
         [0039]      FIG. 18  is a partial plan view of a rotating roll being a variation example of the invention.  
         [0040]      FIG. 19  is a graph showing the relation between the blade projection pitch and the degree of cleaning.  
         [0041]      FIG. 20  is a graph showing the relation between the blade projection pitch and the degree of cleaning.  
     
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0042]     A band-like apparatus cleaning device according to the present invention is described in detail with reference to the drawings in the following.  
         [0043]      FIG. 1 (A),  FIG. 1 (B) and  FIG. 2  show a rough configuration of a band-like apparatus cleaning device  10 , and the band-like apparatus cleaning device  10  is mainly composed of a hollow rotating roll  21 , a cleaning fluid jetting device  31 , a sliding device  41  and a blade device  51 . This band-like apparatus cleaning device  10  is provided in each of a wire part, a press part and a dry part in a paper making stroke, and is made so as to clean away foreign materials such as an adhesive material, fiber and the like stuck on a band-like apparatus  11  such as a wire belt, a press belt, a canvas belt and the like.  
         [0044]     And as shown in  FIG. 2 , the hollow rotating roll  21  supports a hollow supporting shaft  24  so as to be capable of freely turning by means of bearings  23  mounted on left and right sliding stands  42  of the sliding device  41 . And the hollow rotating roll  21  rotates in the traveling direction of the band-like apparatus  11  (direction of arrow in  FIG. 1 (A)) in a state of having the band-like apparatus wound partially round the hollow rotating roll  21 , the band-like apparatus being given a specific tension, and has a number of apertures for shower  25  formed along the circumferential direction. At this time, the hollow rotating roll  21  is provided with a plurality of apertures for shower  25  formed along the roll rotating direction at certain pitches P in the axial direction of the roll.  
         [0045]     Hereupon, the hollow rotating roll  21  is provided with a cutwater ring  27  more inside (at the roll side) than the bearing  23  supporting the hollow supporting shaft  24  and thereby prevents lubricant of the bearing  23  and the like from being splashed over the band-like apparatus  11  wound partially round the hollow rotating roll  21 .  
         [0046]     Although the hollow rotating roll  21  may be forcibly driven, it may be turned being dragged by the band-like apparatus  11  moving in its traveling direction with a certain slippage relative to the band-like apparatus  11 .  
         [0047]     As a material for the hollow rotating roll  21 , special stainless steel is adopted, but any kind of materials being proof against a high-temperature and high-humidity environment in a dry part and being rich in corrosion resistance may be used.  
         [0048]     And the cleaning fluid jetting device  31  has a fixed roll  32  arranged so as to have a certain space inside the hollow rotating roll  21  and is fixed through a hollow supporting shaft  33  by a supporting stand  34  mounted on a sliding stand  42  of the sliding device  41 . A cleaning fluid jetting nozzles  35  is attached to the fixed roll  32  within an embracing angle of the band-like apparatus wound partially round the hollow rotating roll  21  and is arranged closely to and at the inner side of an aperture for shower  25 .  
         [0049]     In such a way, by arranging a cleaning fluid jetting nozzle closely to an aperture for shower  25 , it is possible to decrease a fluid jet pressure necessary for keeping a certain cleaning capability and also reduce the amount of cleaning fluid used. And Decrease of a fluid jet pressure prevents wear and clogging of a cleaning fluid jetting nozzle  35  and thereby makes it possible to prolong the life of the band-like apparatus cleaning device  10 . Further, in a cleaning fluid jetting device  31  at this time, nozzle groups  36  each being composed of a plurality of cleaning fluid jetting nozzles  35  are file-arranged along the longitudinal direction of each aperture for shower  25  (aperture group  26 ) at each pitch P corresponding to each aperture for shower  25  (aperture group  26 ) of the hollow rotating roll  21  in the roll axis direction of the hollow rotating roll  21 .  
         [0050]     And the cleaning fluid jetting device  31  inserts cleaning fluid jetting tubes  37  into the fixed roll  32  from an opening of the hollow supporting shaft  33  and connects cleaning fluid jetting heads  38  composed of square tubes and the like to these cleaning fluid jetting tubes  37 , and a plurality of cleaning fluid jetting nozzles  35  are connected in the longitudinal direction of the cleaning fluid jetting heads  38 . This cleaning fluid jetting head  38  extends from the left or right end of the fixed roll  32  to the middle part of the fixed roll  32 . And the fluid jet pressure from a cleaning fluid jetting nozzle  35  connected to each position in the longitudinal direction of each cleaning fluid jetting head  38  is made to be equal to each other in the longitudinal direction of each cleaning fluid jetting head  38  by reducing gradually the cross-sectional area of each cleaning fluid jetting nozzle  38  as being closer from the left or right end of the fixed roll  32  to the middle of the fixed roll  32 , and the like.  
         [0051]     And the sliding device  41  is made so as to mount a sliding stand  42  on guide rails  44  extending in the axial direction of the hollow rotating roll  21 , the rails being provided on a stand  43  and let this sliding stand  42  support the hollow rotating roll  21  and the cleaning fluid jetting device  31 . This sliding device  41  is made so as to screw-engage a feed screw  46  to be driven by a motor  45  supported by the stand  43  with the sliding stand  42  and make the hollow rotating roll  21  and the cleaning fluid jetting device  31  reciprocate within a range exceeding the pitch P of the aperture group  26  and nozzle group  36  as one body in the roll axis direction of the hollow rotating roll  21  by turning the motor  45  forward and backward.  
         [0052]     And as shown in  FIG. 3 , an aperture for shower  25  of the hollow rotating roll  21  is formed into a long and narrow shape and two parallel slit portions  28  are provided so as to intersect the aperture for shower  25 . Since the slit portions  28  are pushed into the band-like apparatus  11  due to such shock as vibration or the like in a process in which the band-like apparatus  11  is traveling on the roll surface of the hollow rotating roll  21 , the band-like apparatus  11  comes to move in a zigzag direction. As a result, foreign materials which have come into the inside (minute gaps between warp and woof) of the band-like apparatus  11  result in, as shown in  FIG. 4 , being rubbed and kneaded out by so-called rubbing and kneading action at point M and then being scraped away to the outside by so-called scraping-away action at point K. That is to say, thanks to these two actions (rubbing and kneading action and scraping-away action), the band-like apparatus  11  can extend gaps between warp and woof, collect foreign materials being about to come into the inside of the band-like apparatus  11  on the surface of the band-like apparatus  11  and thereby remove a more amount of foreign materials.  
         [0053]     Due to this, it is possible to improve the degree of ventilation of the band-like apparatus  11 , prolong the life of the band-like apparatus  11 , reduce a troublesome maintenance work by reducing the frequency of replacing periodically the band-like apparatus  11 , and reduce the labor cost and the running cost. And since the degree of ventilation is improved, it is possible to make the water of a wet paper web exhale sufficiently through meshes of the band-like apparatus  11  and increase the drying efficiency of paper.  
         [0054]     In this case, since when the width W of an aperture for shower  25  is made broader the band-like apparatus  11  comes to be more liable to move in a zigzag direction and more liable to receive a rubbing and kneading action and a scraping-away action, it is possible to remove more foreign materials from the surface of the band-like apparatus  11 . In the present invention, therefore, experiments were performed with regard to the relation between the aperture for shower  25  and the degree of cleaning.  
         [0055]     First, varying the diameter (face length) of a hollow rotating roll  21 , experiments were performed using rolls for press and canvas with regard to the relation between the slit width of an aperture for shower  25  and the degrees of cleaning and wear of a band-like apparatus. As a result, with regard to a roll for press, as shown in FIGS.  5  to  8 , it has been found that the degrees of cleaning and wear are the most preferable in comprehensive evaluation in case of 8 mm in slit width in S 300 , in case of 10 mm in slit width in S 400 , in case of 10 mm in slit width in S 500 , and in case of 12 mm in slit width in S 600 . On the other hand, with regard to a roll for canvas, as shown in FIGS.  9  to  12 , in consideration of the machining cost of the roll, it has been found that the degree of cleaning is the most preferable in case of 20 mm in slit width in S 300  and S 400 , and in case of 22 mm in slit width in S 500  and S 600 . In a word, from the viewpoint of degree of cleaning, it has been found that it is preferable to set the slit width in a range of 8 to 12 mm with regard to a roll for press and set the slit width in a range of 20 to 22 mm with regard to a roll for canvas.  
         [0056]     That is to say, the degree of cleaning was  11  hours and the degree of wear was 83% in case of 8 mm in slit width using S 300  with regard to a roll for press. And the degree of cleaning was 13 hours and the degree of wear was 79% in case of 10 mm in slit width using S 400 . And the degree of cleaning was 14 hours and the degree of wear was 81% in case of 10 mm in slit width using S 500 . And the degree of cleaning was 14 hours and the degree of wear was 79% in case of 12 mm in slit width using S 600 . On the other hand, with regard to a roll for canvas, the amount of adhesive foreign materials stuck therein being an index of the degree of cleaning was 540 g in case of 20 mm in slit width using S 300 , the amount of adhesive foreign materials stuck therein was 920 g in case of 20 mm in slit width using S 400 , the amount of adhesive foreign materials stuck therein was 750 g in case of 22 mm in slit width using S 500 , and the amount of adhesive foreign materials stuck therein was 550 g in case of 22 mm in slit width using S 600 .  
         [0057]     Hereupon, “S 300 ” is a band-like apparatus cleaning device of 314 mm in roll diameter and 1500 mm to 3400 mm in roll surface length, “S 400 ” is a band-like apparatus cleaning device of 400 mm in roll diameter and 3500 mm to 4900 mm in roll surface length, “S 500 ” is a band-like apparatus cleaning device of 500 mm in roll diameter and 5000 mm to 6200 mm in roll surface length, and “S 600 ” is a band-like apparatus cleaning device of 600 mm in roll diameter and 6300 mm to 7400 mm in roll surface length.  
         [0058]     Next, experiments with regard to the relation between the shape of a slit and the degree of cleaning were performed varying the slits in shape. As a result, as shown in  FIG. 13 , an aperture for shower provided with three cross-shaped slits was the best in cleaning performance in S 300 , S 400  and S 600 , while an aperture for shower provided with three inclined slits was the best in cleaning performance in S 500 .  
         [0059]     By this, it is possible to jet a cleaning fluid jettingted from cleaning fluid jetting nozzles  35  connected to cleaning fluid jetting heads  38  at positions where the cleaning fluid jetting nozzles correspond to a nozzle group  36  to which the respective cleaning fluid jetting nozzles belong from apertures for shower  25  of the hollow rotating roll  21  to a band-like apparatus  11  by a cleaning fluid jetting device  31 , while making the cleaning fluid jetting device  31  and the hollow rotating roll  21  reciprocate as one body in the roll axis direction.  
         [0060]     Accordingly, it is possible to clean a band-like apparatus  11  over the whole width of it, and to make the steam being a cleaning fluid jetted from a cleaning fluid jetting device  31  remove and collect foreign materials from the inside of the band-like apparatus  11  on the surface of the band-like apparatus  11 . And since it is possible to clean the band-like apparatus  11  over the whole width of it and remove foreign materials, the moisture profile of paper is made stable. That is to say, no undried portion appears in a sheet of paper and paper being good in quality is obtained.  
         [0061]     And as shown in  FIG. 1 (A), a blade device  51  is provided with two blade plates  52 , and a save-all  53  is provided under the blade plates  52 . Light fibers (paper powder) and the like are made to fall in the save-all  53  at the entrance side of a blade portion  54  but foreign materials stuck on the band-like apparatus  11  which have not been made to fall even by slit portions  28  of apertures for shower  25  of the hollow rotating roll  21  as described above are scraped away by the blade plates  52 .  
         [0062]     This blade device  51  scrapes away foreign materials stuck on the surface of the band-like apparatus  11  by pressing the edges  55  of the blade plates  52  against the surface of the band- like apparatus  11  at a certain pressure. The scraped-away foreign materials stay on the surface of the band-like apparatus  11  pressed by the edges  55 , adhere to one another at the back side of the edges  55  of the blades  52 , and expand and grow in the shape of a strip of paper. Therefore, it is possible to securely remove the foreign materials stuck on the surface of the band-like apparatus  11  without scattering them around. And the band-like apparatus  11  is not worn by the scraping of the blades  52 , and further the warp of the band-like apparatus  11  is not degraded in strength.  
         [0063]     As shown in  FIG. 14 , the edge of a blade plate  52  has a shape capable of efficiently expanding and growing foreign materials into the shape of a strip of paper, namely, the two blade plates  52 A and  52 B have notches  56 A and  56 B corresponding to pitches P of the apertures for shower  25  of the hollow rotating roll  21 , and the two blade plates  52 A and  52 B are mounted so that these notches  56 A and  56 B are arranged alternately zigzag.  
         [0064]     Due to this, when a band-like apparatus cleaning device  10  operates, if it is a flat single plate having no notch, the whole device vibrates and a band-like apparatus  11  is made wavy and results in vibrating up and down in a process of carrying the band-like apparatus  11 , and parts where the band-like apparatus  11  comes into contact with and no contact with the blade plates  52  appear. As a result, parts from which foreign materials are scraped away and not scraped away by the blade plates  52  appear, but by providing such notches in the blade plates  52 , the band-like apparatus  11  is made to come into contact with the blade plates at locations  57  without fail. Therefore, by installing blade plates  52  so that notches  56 A and  56 B of the blade plates  52 A and  52 B are alternately arranged, it is possible to bring the blade plates  52  uniformly into contact with the whole surface of the band-like apparatus  11 . And by providing such notches in the blade plates  52 , it is possible to concentrate the actions of heat and contact pressure at the contact parts between the edges  55  of the blade plates  52  and the band-like apparatus  11 , efficiently expand and grow foreign materials, remove the expanded and grown foreign materials in a state where they are formed into a strip shape, collect the foreign materials in a state where they are scattered in the save-all  53 , and prevent a drainpipe of the save-all  53  from getting clogged.  
         [0065]     And a blade device  51  of a band-like apparatus cleaning device  10  according to the invention is not limited to the case of providing two blade plates  52 A and  52 B as described above, but may be provided with three blade plates  52 A′,  52 B′ and  52 C′ at specified pitches, as shown in  FIG. 15  for example. That is to say, it is enough to provide a plurality of blade plates  52  so that they form a flat single plate having no notches when they are superposed one over another.  
         [0066]     And the shapes of apertures for shower  25  and slit portions  28  are not limited to the shapes as described above, but such shapes as the pitch, width and length of an aperture for shower  25  and the number of slits and the like may be determined depending on a kind of the band-like apparatus  11  and an embracing angle of the band-like apparatus  11  wound partially round the hollow rotating roll  21 , and the shape of them may be, for example, a shape where three slit portions  28  are provided perpendicularly to the longitudinal direction of an aperture for shower  25  as shown in  FIG. 16 , a shape where three parallel slit portions  28  are provided at an inclined angle relative to the longitudinal direction of an aperture for shower  25  as shown in  FIG. 17 , or a shape where slit portions  28  are crossed in the shape of X as shown in  FIG. 18 , so that a rubbing and kneading action and a scraping-away action as described above efficiently exert on the band-like apparatus  11 .  
         [0067]     Thereupon, experiments were performed with regard to the relation between the blade projection pitch and the degree of cleaning, varying the number of blade plates  52 . As a result, as shown in  FIG. 19 , the largest amount of foreign materials (about 1500 g) could be collected in case of using three blade plates and a blade projection pitch of 20 to 40 mm, preferably, 30 mm as shown in  FIG. 19 . And the degree of cleaning was the most preferable in case of the blade projection pitch of 25 mm as shown in  FIG. 20 .  
         [0068]     And since a band-like apparatus  11  can be cleaned uniformly over the whole width of it by providing a plurality of blade plates  52  provided with notches as described above to form a flat single plate having no notches when they are superposed one over another and further providing a flat blade plate, a flat blade plate having no notches may be provided.  
         [0069]     And although the present invention adopts stainless steel as a material for a blade plate  52 , any kind of materials being proof against a high-temperature and high-humidity environment in a dry part and being rich in corrosion resistance may be used.  
         [0070]     And in a band-like apparatus cleaning device  10 , a band-like apparatus  11  may be wound partially round a hollow rotating roll  21  setting a dirt-resistant surface of the band-like apparatus  11  as the inner face to be in contact with the hollow rotating roll  21 , and may be wound partially round the hollow rotating roll  21  setting a surface of the band-like apparatus  11  as the outer face of the band-like apparatus  11  to be in no contact with the hollow rotating roll  21 .