JP2005232631A - Net for concentrating pulp and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To achieve high durability resisting to a long-term use by suppressing the break of a net body. <P>SOLUTION: A guide part 7 installed along the edge in the width direction of the net body 6 to regulate the position in the width direction based on a roll of the net body 6 to be wound on the roll is formed by installing a reinforced part 8 obtained by reinforcing the net body by a synthetic polymer material in a region inside the guide part. The reinforced part is formed by fixing reinforcing sheets 12 and 13 having different flexibilities to the net body to form a high rigidity region 15 at the vicinity part of the guide part, and to form a low rigidity region 16 at the inside part neighboring to the ground part of the net body. Preferably, the reinforced sheet is fixed to the net body through a hot-melt adhesive sheet 14 comprising a thermoplastic synthetic polymer material. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a pulp concentrating net for compressing and concentrating (dehydrating) pulp, and a method for producing the same, and in particular, in order to define the width direction position of the net main body wound around the roll in an endless manner. The present invention relates to a pulp concentrating net provided with a guide portion along an edge in the width direction thereof and a manufacturing method thereof.

  In the recycling of waste paper, various processes such as disaggregation, deinking, and bleaching are performed, but in the deinking process that separates and removes foreign matter such as ink and clay from the raw paper raw material, it is wound around a roll. Pulp concentrators that squeeze and condense (dehydrate) pulp with a net are used.

  In such a pulp concentrator, the pulp is supplied as a lump of a non-uniform size on the net, so that the load balance in the entire net is lost and the net is liable to skew. Therefore, in order to suppress such skewing of the net, a structure in which a guide body that defines the position in the width direction with respect to the roll is provided along the edge in the width direction of the net is used.

As a net provided with this type of guide body, for example, a structure in which a guide body having a trapezoidal cross section is fixed to a net body by stitching is known (see Patent Document 1). Further, a structure in which a guide body is fixed to a net body by fusion is known (see Patent Documents 2 and 3).
JP-A-2-14090 JP-A-4-361682 JP-A-8-144185

  However, in the net provided with the guide body, a large bending stress is generated in the net body in the vicinity of the guide body in a state of being wound around the outer peripheral surface of the roll, and such a stress state is repeatedly generated during traveling. As a result, the strength of the fiber of the net body is reduced, and the fiber of the net body is cut and unusable after a short period of use.

  For example, in the configuration in which the guide body is fixed to the net body by stitching as described in Patent Document 1, a problem occurs in that the net of the net body is bent in the immediate vicinity of the guide body and the fibers of the net body are cut. On the other hand, in the configuration in which the anti-bending portion is provided integrally with the guide body as described in Patent Documents 2 and 3, it is possible to suppress bending of the net body in the immediate vicinity of the guide body, but reinforcement is applied. The stress concentrates on the boundary between the ground part and the anti-bending part of the mesh body that has not been done, and there is a problem that the fiber of the mesh body cuts along the boundary part, sufficiently satisfying the demand for improved durability Can not do it.

  The present invention has been devised to solve such problems of the prior art, and its main purpose is high durability that can withstand long-term use by suppressing fiber cutting of the net body. Is to provide a pulp concentration net and a method for producing the same.

  In order to solve such a problem, in the present invention, as shown in claim 1, in order to define the position in the width direction of the net body wound around the roll relative to the roll, the edge in the width direction of the net body In the pulp concentrating net provided with a reinforcing part in which the net body is reinforced with a synthetic polymer material in an inner region from the guide part, the reinforcing part has flexibility. By fixing a plurality of different reinforcing sheets to the net body, a high-rigidity region was formed in the vicinity of the guide portion, and a low-rigidity region was formed in the inner portion adjacent to the ground portion of the net body. .

  According to this, since the low rigidity region is adjacent to the base portion of the net body that is not reinforced with the synthetic polymer material, it is avoided that the rigidity changes greatly at the boundary portion between the base portion and the reinforcing portion of the net body. be able to. For this reason, the stress concentration at the boundary portion between the ground portion and the reinforcing portion of the net body can be alleviated, whereby the net body can be prevented from breaking and durability can be enhanced. In addition, since the high-rigidity region is formed in the vicinity of the guide portion, the guide portion is held relatively firmly, so that stable guide performance can be ensured.

  Furthermore, since the mechanical characteristics of the reinforcing part can be changed in various ways by changing the reinforcing sheet to be combined, it is appropriate for the conditions of use such as the form of the installed pulp concentrator and the characteristics of the pulp to be processed. It is possible to easily manufacture a variety of specification nets.

  In the said pulp concentration net | network, as shown in Claim 2, the some said reinforcement sheet | seat can take the structure which consists of a synthetic polymer material from which hardness mutually differs. According to this, by selecting a synthetic polymer material having a required hardness, the high rigidity region and the low rigidity region can be set to appropriate rigidity.

  In this case, it is preferable to use a reinforcing sheet made of synthetic polymer materials of different grades belonging to the same system and having different hardnesses. In addition, the reinforcing sheet may be made of the same synthetic polymer material, and the thickness thereof may be changed. Even in this configuration, since the flexibility of the reinforcing sheet is different, a high-rigidity region and a low-rigidity region can be formed in the reinforcing portion.

  In the said pulp concentration net | network, as shown in Claim 3, the said reinforcement sheet | seat which forms the said low rigidity area | region can take the structure which makes | forms mesh shape. According to this, flexibility can be improved without changing the material of the reinforcing sheet. Moreover, as the structure in which the reinforcing sheet itself is thermally melted and fixed to the net body, the water permeability can be ensured by filling the material into the woven structure of the net body so that the mesh opening is not crushed. Even when the width of the reinforcing portion is wide, it is possible to avoid a significant decrease in the concentration (dehydration) capacity.

  In this case, the flexibility and water permeability of the low-rigidity region can be adjusted according to the opening ratio of the mesh of the reinforcement sheet, and the appropriate flexibility and The thing of the aperture ratio which can obtain water permeability should just be employ | adopted.

  Moreover, in this invention, in order to prescribe | regulate the width direction position with respect to the said roll with respect to the said roll, the guide part is provided along the width direction edge of the said net body as shown in Claim 4. In addition, in the method of manufacturing a pulp concentration net provided with a reinforcing portion in which the net body is reinforced with a synthetic polymer material in an inner region from the guide portion, a plurality of reinforcing sheets having different flexibility are provided on the net body. The reinforcing portion is formed by adhering to an edge portion, and at this time, the relatively hard reinforcing sheet is disposed in the vicinity of the guide portion, and the inner portion adjacent to the ground portion of the net body is relatively soft. The said reinforcing sheet shall be arranged.

  According to this, a high-rigidity area is formed in the vicinity of the guide part, and a low-rigidity area is formed in the inner part adjacent to the net part of the net body. The stress concentration at the boundary between the ground part and the reinforcing part can be relaxed, so that the net body can be prevented from breaking and the durability can be improved. On the other hand, the high rigidity area near the guide part ensures stability. Guide performance can be ensured.

  In the method for manufacturing the pulp concentration net, as shown in claim 5, the reinforcing sheet is fixed to the net body via a heat-weldable adhesive sheet made of a thermoplastic synthetic polymer material. be able to. According to this, the reinforcing sheet and the adhesive sheet may be superposed on one surface of the net body and ultrasonically welded, and the manufacture becomes easy. And it can suppress that the reinforcement sheet heat-melts at the time of adhering, and can suppress the wrinkle of the net | network body which arises after heat welding.

  In addition, in order to fix the reinforcing sheet to the net body, it is also possible to use an adhesive whose initial state is liquid like a two-component type or a solvent type. In addition, the reinforcing sheet is made of a thermoplastic synthetic polymer material, and the reinforcing sheet can be fixed to the net body by filling the material itself into the woven structure of the net body by heat melting.

  As described above, according to the present invention, the stress concentration at the boundary between the ground portion of the net body and the reinforcing portion is reduced by the low rigidity region formed in the portion adjacent to the ground portion of the net body in the reinforcing portion. Since the breakage of the net body can be effectively suppressed, a great effect can be obtained in enhancing the durability.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a sectional view schematically showing a pulp concentrator equipped with a pulp concentrating net according to the present invention. This pulp concentrator removes moisture from pulp in a process of separating and removing foreign matters such as ink and clay from waste paper raw materials, and concentrates the endless net 1 according to the present invention into a pair of rolls 2 and 3. It is wrapped around.

  In this pulp concentrator, the pulp is supplied from the supply unit 4 between the roll 2 and the net 1, and the pulp is pressed between the net 1 and the peripheral surfaces of the rolls 2 and 3, so that the moisture in the pulp is the outer surface of the net 1. The pulp discharged to the side and concentrated is collected by the collection unit 5.

  FIG. 2 is a cross-sectional view of the pulp concentration net shown in FIG. 1 cut in the width direction. The net 1 is provided with a guide portion 7 provided along an edge in the width direction of the net body 6 in order to define the width direction position with respect to the rolls 2 and 3, thereby suppressing the skew of the net 1. be able to. The guide portion 7 is provided in a state protruding from the surface facing the outer peripheral surface of the rolls 2 and 3 and is engaged with the end surfaces of the rolls 2 and 3.

  In addition, a reinforcing portion 8 in which the net body 6 is reinforced with a synthetic polymer material is provided in a region inside the guide portion 7 in order to suppress bending of the net body 6 in the vicinity of the guide portion 7.

  Here, the guide portion 7 is engaged with the end faces of the rolls 2 and 3, but a configuration in which the guide portion 7 is engaged with an annular groove provided on the outer periphery of the rolls 2 and 3 is also possible.

  FIG. 3 shows a first embodiment of the pulp concentration net shown in FIG. (A) shows a cross section in a state before assembly, (B) shows a cross section in a completed state, and (C) shows a change in rigidity. Here, the guide part 7 is heat-sealed to the surface 6a of the net body 6 on the side facing the rolls 2 and 3, with the guide part forming body 11 having a trapezoidal cross section formed of a thermoplastic synthetic polymer material. It is formed by doing.

  The guide part forming body 11 is made of, for example, thermoplastic polyurethane and can be obtained by extrusion molding.

  The guide portion forming body 11 may be ultrasonically welded so as to overlap the surface 6 a of the net body 6, whereby the contact portion with the net body 6 is thermally melted, and the synthetic polymer material of the net body 6 The filling layer 17 is formed by filling the fabric structure, and the guide portion forming body 11 and the net body 6 are firmly joined.

  A plurality of (in this case, two) reinforcing sheets 12 and 13 having different flexibility are fixed to the net body 6 at the reinforcing portion 8, so that a high-rigidity region 15 is provided in the vicinity of the guide portion 7 and a synthetic polymer. Low rigidity regions 16 are respectively formed in the inner portion adjacent to the ground portion of the net body 6 that is not reinforced by the material. These reinforcing sheets 12 and 13 are fixed to the surface 6b of the net body 6 opposite to the surface 6a on which the guide portion 7 protrudes through a heat-weldable adhesive sheet 14 made of a thermoplastic synthetic polymer material. Is done.

  The reinforcing sheets 12 and 13 may be ultrasonically welded with the adhesive sheet 14 sandwiched between the net body 6, whereby the synthetic polymer material of the adhesive sheet 14 is melted by heat and the inside of the woven structure of the net body 6. Of the adhesive sheet 14 filled with the reinforcing sheets 12 and 13 and the fabric structure of the net body 6. Due to the synthetic polymer material, the reinforcing portion 8 exhibits higher rigidity than the ground portion of the net body 6.

  The reinforcing sheets 12 and 13 are made of a synthetic polymer material of the same system and different in hardness, such as polyurethane, and the reinforcing sheet 13 that forms the low-rigidity region 16 is compared with the reinforcing sheet 12 that forms the high-rigidity region 15. It is made of a soft grade synthetic polymer material, whereby the low-rigidity region 16 exhibits intermediate rigidity between the high-rigidity region 15 near the guide portion 7 and the ground portion of the net body 6. It is possible to avoid a significant change in rigidity at the boundary between the ground portion and the reinforcing portion 8.

  The adhesive sheet 14 is made of the same type of synthetic polymer material having a softening point lower than the softening point (for example, 230 ° C.) of the reinforcing sheets 12 and 13, for example, polyurethane having a softening point of 140 ° C. Thereby, it can suppress that the reinforcement sheets 12 * 13 heat-melt at the time of heat welding, and can suppress the wrinkle of the net | network main body 6 which arises after heat welding.

  The reinforcing sheet may be made of the same synthetic polymer material, and the flexibility may be changed by different thicknesses. In this configuration, a high rigidity region can be formed by a thick reinforcing sheet, and a low rigidity region can be formed by a thin reinforcing sheet.

  Moreover, the structure which adheres the reinforcement sheets 12 * 13 to the net | network main body 6 with an adhesive agent is also possible. In this case, as the adhesive, for example, polyurethane dissolved in a solvent such as toluene or MEK may be used.

  FIG. 4 shows in detail the main part of the pulp concentration net shown in FIG. The net body 6 has a triple woven fabric structure, more specifically, a triple woven fabric structure composed of upper and lower two layers. The warp yarn 101 and the weft yarn 102 constituting the surface structure on the side to which the pulp is supplied are made of, for example, polyester monofilament. On the other hand, the warp yarn 103 constituting the back surface structure is made of, for example, polyester monofilament, and the weft 104 of the back surface structure is made of a monofilament of a polyamide-based synthetic resin material that is rich in flexibility. In addition, the textile structure of the net body in the present invention is not limited to this.

  FIG. 5 shows a second embodiment of the pulp concentration net shown in FIG. (A) shows a cross section in a state before assembly, (B) shows a cross section in a completed state, and (C) shows a change in rigidity. Here, as in the above example, the reinforcing portion 8 including the high rigidity region 25 and the low rigidity region 26 is formed by the reinforcing sheets 22 and 23 having different flexibility. Unlike the above-described example, the synthetic polymer material itself is fixed to the net body 6 by being filled into the fabric structure of the net body 6 by heat melting.

  The reinforcing sheets 22 and 23 are made of synthetic polymer materials of the same system having different hardness, such as polyurethane, as in the above example, and the reinforcing sheet 23 forming the low-rigidity region 26 is a reinforcing member that forms the high-rigidity region 25. It is made of a synthetic polymer material of a softer grade than the sheet 22.

  In this configuration, the filler layer 17 is formed by the thermal melting of the guide portion forming body 11 and the filler layers 28 and 29 are formed by the thermal melting of the reinforcing sheets 22 and 23, respectively. The situation is the same as the example shown in FIG.

  If the reinforcing sheet 23 forming the low-rigidity region 26 is configured to have a tapered cross section whose thickness gradually decreases inward, the low-rigidity region 26 has a characteristic that the rigidity gradually decreases inward. As shown, the change in rigidity can be made more gradual.

  FIG. 6 shows a third embodiment of the pulp concentration net shown in FIG. (A) shows the top surface of the reinforcing sheet, (B) shows the cross section before assembly, (C) shows the cross section in the completed state, and (D) shows the change in rigidity. Here, as in the above example, the reinforcing sheets 22 and 33 are fixed to the net body 6 by heat melting. However, unlike the above example, the reinforcing sheet 33 forming the low rigidity region 36 has a mesh shape. There is no.

  In the low-rigidity region 36, the amount of the synthetic polymer material filled in the woven fabric structure of the net body 6 is reduced overall by the mesh-like reinforcing sheet 33, so that even a synthetic polymer material having the same hardness is low. Indicates rigidity. The rigidity of the low-rigidity region 36 can be changed according to the opening ratio of the mesh of the reinforcing sheet 33, and can be set to an appropriate rigidity according to use conditions and the like.

  In the low-rigidity region 36, a portion not filled with the synthetic polymer material is formed corresponding to the opening of the reinforcing sheet 33, and water permeability can be secured here, so that the width of the low-rigidity region 36 is widened. Even with this configuration, a significant decrease in concentration (dehydration) capacity can be avoided.

  In addition, when the opening ratio is gradually increased with the reinforcing sheet 33 facing inward, for example, the diameter of the opening is gradually increased, the low-rigidity region 36 has a characteristic that the rigidity gradually decreases toward the inner side. Changes can be made even more gradual.

  FIG. 7 shows a fourth embodiment of the pulp concentration net shown in FIG. (A) shows a cross section in a state before assembly, and (B) shows a cross section in a completed state. Here, similar to the above example, the reinforcing portion 8 composed of the high rigidity region 15 and the low rigidity region 16 is formed by the reinforcing sheets 12 and 13 having different flexibility, but unlike the above example, the guide portion 7 is formed with the guide part formation body 41 which consists of a nonwoven fabric aggregate.

  The guide part forming body 41 is formed by adhesively bonding the constituent fibers of the nonwoven fiber assembly with a fiber binding material (binder). After the nonwoven fiber assembly is formed by needle punching, this nonwoven fabric assembly is formed. It is produced by impregnating a fiber assembly with a fiber binding material.

  For example, polyester fibers excellent in shape retention performance are suitable for the constituent fibers of the nonwoven fiber aggregate. On the other hand, as the fiber binding material, a synthetic polymer material that is familiar with the constituent fibers and excellent in adhesiveness may be used. In addition, the mechanical properties such as elasticity of the guide portion forming body 41 can be changed depending on the material and the amount of the fiber bonding material, and therefore the selection may be made as appropriate according to the performance required for the guide portion 7.

  The guide part forming body 41 is fixed to the net body 6 by an adhesive 42 whose initial state is liquid like a two-component type or a solvent type. The adhesive 42 is filled in the gaps of the guide portion forming body 11 and is filled in the fabric structure of the net body 6 to form the filling layer 17, whereby the guide portion forming body 11 and the net body 6 are firmly connected. To be joined. The adhesive 42 is preferably a polyurethane-based material having excellent extensibility and durability.

  FIG. 8 shows a fifth embodiment of the pulp concentration net shown in FIG. (A) shows a cross section in a state before assembly, and (B) shows a cross section in a completed state. Here, as in the example shown in FIG. 5, the reinforcing sheets 51 and 23 are fixed to the net body 6 by filling the fabric structure of the net body 6 by thermal melting of the synthetic polymer material itself. Unlike the above example, the reinforcing sheet 51 forming the high-rigidity region 52 is made of a sheet-like composite material having a reinforcing thread in a synthetic polymer material.

  FIG. 9 is an enlarged view of the reinforcing sheet shown in FIG. The reinforcing sheet 51 is formed by laminating a composite material layer 66 in which a base fabric 65 made of reinforcing yarns 61 to 64 is impregnated with a synthetic polymer material (matrix resin) and a film layer 67 made of a synthetic polymer material (polyurethane). The structure is made. The fabric 65 of the composite material layer 66 has lengthwise yarns (warp yarns) 61 and 63 and widthwise yarns (weft yarns) 62 and 64, and is made of a multi-woven fabric such as a double weave or a plain weave. A plurality of woven fabrics are laminated. Reinforcing yarns 61 to 64 are preferably polyurethane or polyester. In addition, any material that suppresses elongation and improves strength may be used. Polyamide such as nylon, PEEK, and aramid fibers such as Kevlar (manufactured by DuPont) Is possible.

  In this configuration, the synthetic polymer material of the film layer 67 of the reinforcing sheet 51 is thermally melted and filled into the fabric structure of the net body 6 to form the filling layer 53. The base fabric 65 of the reinforcing sheet 51 The main body 6 overlaps in the thickness direction. Thereby, the rigidity of the high rigidity area | region 52 of the vicinity of the guide part 7 can be improved further, and it can improve durability while improving guide performance.

  In the above example, the synthetic polymer material used for the guide portion forming body, the reinforcing sheet, and the adhesive sheet is polyurethane. However, the present invention is not limited to this, and for example, polyvinyl chloride, polyamide (Nylon), polyester, etc. are also possible. In particular, polyurethane is excellent in terms of mechanical strength and wear resistance, and also has good adhesion to the textile fibers (polyester) of the net body.

  Further, a mode in which a reinforcing sheet made of a sheet-like composite material having a reinforcing thread in a synthetic polymer material is fixed to the net body through a heat-weldable adhesive sheet as in the example shown in FIG. 3 is also possible. . Furthermore, since a reinforcing sheet made of a sheet-like composite material having reinforcing yarns has high rigidity, it may be used only for the reinforcing sheet arranged on the outside. It is also possible to employ a configuration in which the flexibility of the reinforcing sheet is adjusted depending on the thickness and number of reinforcing yarns.

  The pulp concentrating net according to the present invention has an effect of effectively suppressing breakage of the net body and enhancing durability, and is used by being attached to a pulp concentrator that compresses and concentrates (dehydrates) pulp. Useful for. Further, the method for producing a pulp concentration net according to the present invention is useful for use in producing the pulp concentration net having the above-described configuration.

It is sectional drawing which shows typically the pulp concentration machine with which the net | network for pulp concentration by this invention is mounted | worn. It is sectional drawing which cut | disconnected the net for pulp concentration shown in FIG. 1 in the width direction. It is a conceptual diagram which shows 1st Embodiment of the net for pulp concentration shown in FIG. It is sectional drawing which shows the principal part of the mesh for pulp concentration shown in FIG. 3 in detail. It is a conceptual diagram which shows 2nd Embodiment of the pulp concentration net | network shown in FIG. It is a conceptual diagram which shows 3rd Embodiment of the pulp concentration net | network shown in FIG. It is a conceptual diagram which shows 4th Embodiment of the net for pulp concentration shown in FIG. It is a conceptual diagram which shows 5th Embodiment of the pulp concentration net | network shown in FIG. It is sectional drawing which expands and shows the reinforcement sheet | seat shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Net | network 2/3 Roll 6 Net | network main body 7 Guide part 8 Reinforcement part 11 * 41 Guide part formation body 12,13,22,23 * 33 * 51 Reinforcement sheet | seat 14 Adhesive sheet | seat 15 * 25 * 52 High rigidity area | region 16 * 26 * 36 Low rigidity region 42 Adhesive

Claims (5)

In order to define the width direction position of the net body wound around the roll with respect to the roll, a guide part is provided along an edge in the width direction of the net body, and the net body is provided in an inner region from the guide part. A pulp concentrating net provided with a reinforcing portion reinforced with a synthetic polymer material,
A plurality of reinforcing sheets having different flexibility are fixed to the mesh body at the reinforcement portion, so that a high rigidity region is provided in the vicinity of the guide portion and a low rigidity is provided in an inner portion adjacent to the ground portion of the mesh body. A pulp concentrating net characterized in that each region is formed.   2. The pulp-concentrating net according to claim 1, wherein the plurality of reinforcing sheets are made of synthetic polymer materials having different hardnesses.   2. The pulp concentration net according to claim 1, wherein the reinforcing sheet forming the low-rigidity region has a mesh shape. In order to define the width direction position of the net body wound around the roll with respect to the roll, a guide part is provided along an edge in the width direction of the net body, and the net body is provided in an inner region from the guide part. A method for producing a pulp concentrating net provided with a reinforcing portion reinforced with a synthetic polymer material,
A plurality of reinforcing sheets having different flexibility are fixed to an edge portion of the net body to form the reinforcing portion, and at this time, the relatively hard reinforcing sheet is disposed in the vicinity of the guide portion, A method for producing a pulp-concentrating net, comprising arranging the relatively soft reinforcing sheet on an inner part adjacent to a base part of a net body.   The method for producing a net for pulp concentration according to claim 4, wherein the reinforcing sheet is fixed to the net body through a heat-welding adhesive sheet made of a thermoplastic synthetic polymer material.

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