JP5703040B2 - Joint structure of endless filter cloth - Google Patents

Description

The present invention relates to a joint structure for an endless filter cloth.

An endless filter cloth is used for a filter or a dehydrator such as a horizontal belt filter, a belt filter, a belt press, and a drum filter. Conventionally, as shown in Patent Document 1 and FIG. 11 described later, a common hole formed by connecting metal hooks having a narrow width of about 1 mm to joint portions at both ends of a filter cloth and alternately engaging them. Both ends were joined by inserting a metal or synthetic resin core into the endless filter cloth.

The metal hook has a problem that it is plastically deformed by use and the hooks do not mesh with each other, making it difficult to pass the core wire. Further, even if no deformation occurs, the hooks are likely to be hooked easily due to the large number, and it takes time for the joining work. Furthermore, after engaging, there is a problem that when the core wire is inserted through the common hole, the hook is displaced, or the core wire is caught on the hook, so that the core wire cannot be inserted smoothly and time is required for the joining work. there were. The filter cloth used for a filter such as a horizontal belt filter is long, and the time required for joining the filter cloth decreases the efficiency of the filtering work.

Moreover, in the joint structure which meshes | joins and joins hooks like patent document 1, since a clearance gap is made in a junction part, a synthetic resin is apply | coated to a junction part as described in patent document 1, or a junction part There was a need to prevent leakage by attaching a cover made of a piece of filter cloth or the like with a hook-and-loop fastener or the like. Since the endless filter cloth used for horizontal belt filters, etc. is constantly tensioned, the cover is not sufficiently affixed with a hook-and-loop fastener, and there is a problem that the cover peels off when the endless filter cloth is rotated. .

On the other hand, Patent Document 2 describes that a bag portion is formed at an end portion of a filter cloth and the bag portions are alternately cut out to form a joint structure. The support bar 6 is inserted through a common hole formed by meshing the notched bag portions, and two filter cloths are joined.

The filter cloth of Patent Document 2 is a filter cloth for a filter press, and at the time of filtration, a filter plate is strongly pressed against the surface of the filter cloth to form a filter chamber (see FIGS. 1 and 2 of Patent Document 2). Since the joint portion of the filter cloth is not directly related to filtration, the cited document 2 does not consider the opening of the joint portion during tension. Further, the size of the filter cloth for the filter press is not so large, and Patent Document 2 does not consider the efficiency of the joining work.

Japanese Patent Laid-Open No. 9-294906 JP 2007-44641 A

An object of the present invention is to provide a joint structure of an endless filter cloth that can be easily joined even with a long filter cloth and that causes less cake leakage due to the opening of the joint.

In the present invention, an endless filter cloth is formed by joining both ends of a filter cloth by inserting a core wire into a common hole formed by alternately engaging loop-shaped joints provided at joints at both ends of the filter cloth. In the joint structure, the joint structure is a large pitch formed by continuously connecting a plurality of small joints having a width of 3 to 10 mm to the joint portion and a plurality of large joints having a width of 20 to 100 mm to the joint portion. and a pitch portion, the placed at the junction of the small pitch portion are placed insert the core wire starting end and the terminating side, the large-pitch portion coordinated between the small pitch portion, the narrow joint provided in small pitch portion The above problem is solved by an endless filter cloth joint structure in which the number is 2 to 20 per small pitch portion based on the state where both ends of the filter cloth are joined .

Moreover, in this invention, you may provide a 2nd junction part inside a junction part, and may comprise both joint parts as a joint structure which consists of the above-mentioned small pitch part and a large pitch part. That further provided a second joint on the inner side of the joint portion of both ends of the filter cloth, the second joint, connecting a plurality of narrow joint 3~10mm width arranged at the starting end and terminating end of the second connecting portion a small pitch portion formed by setting, which possess a large pitch portion formed by continuously provided several significant joint arranged are 20~100mm width between the small pitch portion, the small pitch of the second joint portion The number of the narrow joints provided in the part is an endless filter cloth joint structure in which the number of the narrow joints is 2 to 20 per one small pitch part on the basis of the state where both ends of the filter cloth are joined .

As described above, the endless filter cloth is used for a horizontal belt filter or the like. In a horizontal belt filter or the like, since filtration is performed while rotating a large filter cloth supported by a plurality of rotation shafts, tension is always applied to the filter cloth. In the present invention, a narrow joint is continuously provided at the joint between the start end side and the end end side into which the core wire is inserted to form a small pitch portion. Thereby, it becomes possible to effectively prevent the opening on the joining start end side and the end side (so-called filter cloth ear portions) of the filter cloth. On the other hand, a plurality of large joints are connected to the middle joint portion sandwiched between the filter cloths on the start end side and the end end side to form a large pitch portion. Thus, the core wire is not caught by the plurality of hooks, and the core wire can be inserted smoothly.

The width of each narrow joint is preferably in the range of 3 to 10 mm, more preferably 4 to 8 mm. Below this range, it is not preferable because the core wire is easily caught by the narrow joint when the core wire is inserted. On the other hand, if it exceeds this range, the opening of the filter cloth and the warp tend to occur at the time of filtration, which is not preferable.

The large joint preferably has a width of 10 to 150 mm, more preferably 20 to 100 mm. Below this range, when inserting the core wire, the core wire is likely to be easily caught by the joint, and the efficiency of the operation of inserting the core wire is lowered, which is not preferable. On the other hand, if it exceeds this range, an opening tends to occur in the middle of the joint of the filter cloth during filtration, which is not preferable.

The large joint and the narrow joint may be formed by folding the end portion of the filter cloth to form a bag portion, and cutting it out so as to have the above-mentioned width to form a narrow joint and a large joint. Alternatively, the end portion of the filter cloth may be covered with a woven or knitted fabric so as to have a U-shaped cross section, and a bag portion may be formed. The latter case is preferable because the joint can be easily replaced by replacing the woven or knitted fabric when the joint is damaged. In addition, since the material can be selected independently of the type of the filter cloth, it is possible to select an optimal material for the material of the joint, which is preferable. When using a knitted or knitted fabric for forming a joint, the joint can be efficiently formed by cutting out by laser processing before attaching to the end of the filter cloth.

When notching a narrow joint and a large joint, it can be cut out accurately by irradiating with laser light. Thereby, the clearance gap formed in a junction part can be made small and the leakage of the cake from a junction part can be minimized.

The number of narrow joints provided in the small pitch part is preferably 2 to 20 per one small pitch part on either the start end side or the end side, based on the state where both ends of the filter cloth are joined, More preferably, it is 4-10. The number of narrow joints here is the number on either the start side or the end side of the filter cloth. Therefore, when a small pitch part is equally arrange | positioned right and left on the start end side and the termination | terminus side, it will be 4-40 pieces (more preferably 8-20 pieces) of narrow joints in the whole filter cloth. Below this range, the opening of the filter cloth is likely to be open, which is not preferable. Exceeding this range is satisfactory in that no meshing occurs, but it is not preferable because workability of the joining work is lowered. What is necessary is just to determine suitably the number of the large joints provided in a large pitch part according to the filter cloth size.

It is possible to perform the joining work without hooking the core wire to the joint by the large pitch part arranged between the small pitch parts while preventing the opening of the filter cloth end by the small pitch part arranged on the ears of the filter cloth Become.

By providing the second joint with a slight shift inside the joint and applying the above joint structure having a large pitch and a small pitch at both joints, cake leakage and joint opening are more effective. Can be prevented. Since the joining work can be easily performed, the work burden due to an increase in the number of joining points can be reduced.

It is the perspective view which showed the edge part of the endless filter cloth which applied the joint structure of the endless filter cloth of this invention. The endless filter cloth is originally cylindrical, but a part other than the end part of the endless filter cloth and a part of the large pitch part are omitted as shown by a one-dot chain line. It is the perspective view which showed a mode that the endless filter cloth of FIG. 1 was meshed | engaged and a core wire was inserted. It is AA sectional drawing of FIG. It is the schematic diagram which showed the procedure of joining of the joint structure of the endless filter cloth of this invention. It is the schematic diagram which showed the procedure of joining of the joint structure of the endless filter cloth which provides a 2nd junction part inside a junction part. It is the schematic of the horizontal belt filter used in the Example. It is the schematic which showed the measuring method of the amount of openings of each experiment example. It is a photograph of the filter cloth of Experimental Example 3 in a state where a load of 10 kg is applied. It is a photograph of the filter cloth of Experimental Example 4 in a state where a load of 10 kg is applied. It is a photograph of the filter cloth of Experimental Example 2 in a state where a load of 10 kg is applied. It is the photograph which image | photographed the conventional joint structure by planar view.

Hereinafter, a specific description will be given with reference to the accompanying drawings.

FIG. 1 is a perspective view showing an end portion of an endless filter cloth 2 to which an endless filter cloth joint structure 1 of the present invention (hereinafter sometimes simply referred to as a joint structure) is applied. Since the endless filter cloth 2 is long, only the upper end portion is shown for convenience of drawing, but when the end portions are connected to each other, a cylindrical endless filter cloth is obtained. The joint structure of the present invention is a small pitch portion in which a plurality of narrow joints 111 (5 per small pitch portion in FIG. 1 and 20 in total endless filter cloth) are connected to the joint portion 21 in succession. 11 and a large pitch portion 12 formed by connecting a plurality of large joints 121 having a width of 20 to 100 mm to the joint portion 21. The small pitch portion 11 is arranged at the joint portion 21 on the start end side and the end end side (FIG. 2) into which the core wire 13 is inserted. The large pitch portion 12 is provided between the small pitch portions 11. About several tens to several hundreds of large pitch portions 12 are connected in series, but for the sake of drawing, in FIG. 1 and FIG. In order for the narrow joint 111 and the large joint 121 at one end of the endless filter cloth 2 to mesh with each other, the narrow joint 111 and the large joint 121 at the other end are cut out to be alternated. When the narrow joint 111 and the large joint 121 are engaged with each other, a common hole is formed by the joint as shown in FIGS. By inserting the core wires 13 (two in the example of FIGS. 2 to 4) into the common hole, the ends of the endless filter cloth 2 are joined to each other.

The narrow joint 111 and the large joint 121 may be formed by looping back the end portion of the endless filter cloth 2 to form a loop-shaped bag portion along the joint portion 21. However, as shown in FIGS. It is preferable to form the woven or knitted fabric 3 having a notch formed by laser processing on the end of the filter cloth 2 so as to have a U-shaped cross section. The woven or knitted fabric is fixed to the endless filter cloth 2 with an adhesive or a suture 31 (FIG. 4). Thereby, as shown in FIG. 2, the clearance gap between junction parts can be made small and the leakage of the cake from a junction part can be minimized.

In order to more effectively prevent cake leakage from the joint, a second joint 22 is provided inside the joint 21 as shown in FIG. The joint portion 21 and the second joint portion 22 are sandwiched between the small pitch portion 11 and the small pitch portion 11 formed by connecting the narrow joint 111 shown in FIG. 1 to the joint portion 21 on the start end side and the end end side. A joint structure having a large pitch portion 12 formed by connecting joints 112 is applied (FIG. 5). In the example of FIG. 5, the knitted and knitted fabric 3 for forming the joint is cut out by laser processing to form the small pitch portion 11 and the large pitch portion 12, and then the suture cloth 31 is applied to the filter cloth 2 inside the joint portion 21. The joint structure of the 2nd junction part was formed by sewing. The endless filter cloth 2 that forms the second joint portion 22 is joined to two common holes formed by meshing the joint of the joint portion 21 at one end and the joint of the second joint portion 22 at the other end. In the example of FIG. 5, two pieces are inserted and joined.

Examples of the present invention will be specifically described below.

[Example 1]
The joint structure having the configuration shown in FIGS. 1 to 4 was produced under the following conditions.
1. Woven knitted fabric 3 for joint formation
A woven / knitted fabric having a 2/2 twill weave using a polypropylene monofilament having a diameter of 0.24 mm was used. The density was 100 warps per inch and 39 wefts per inch.

2. Endless filter cloth 2
For the warp and weft, a woven fabric of 1 / 3-changed diagonal weave using 110 dtex multifilament made of polyethylene terephthalate was used. The density was 210 warps per inch and 98.5 wefts per inch. The endless filter cloth 2 has a width of 500 cm and a length of 1,475 cm. Since the filter cloth is provided with a joint in the width direction, the length of the joint is 500 cm.

The above-mentioned knitted and knitted fabric 3 for forming a joint is cut into a width of 100 cm and a length of 500 cm, and 10 narrow joints each having a width of 5 mm are formed by laser processing on each of the start end side and the end end side through which the core wire 31 is inserted to form a small pitch. Part 11 (20 endless filter cloths as a whole has 20 narrow joints). In addition, 98 large joints with a width of 50 mm were formed between the small pitch portions 11 by laser processing to form large pitch portions 12. The woven / knitted fabric 3 was bent so as to have a U-shaped cross section, and was sewn with sutures 31 to both ends of the endless filter cloth 2.

Two core wires made of polyethylene terephthalate having a diameter of 1.5 mm were inserted through a common hole formed by meshing the joint structure 1 of the endless filter cloth of Example 1, and both ends of the endless filter cloth 2 were joined. Since the joint structure of Example 1 includes the large pitch portion 12, the core wire 13 can be easily inserted, and the mounting of the core wire 13 can be completed in 10 minutes. When the joint part 21 of the endless filter cloth was visually confirmed, it was joined with almost no gap.

[Example 2]
Next, in the joint structure of Example 1, a second joint 22 is further provided inside the joint 21 as shown in FIG. 5, and the joint structure (5 mm) having the same configuration as that of Example 1 is provided at both joints 21 and 22. (Fitting structure having a small pitch portion 11 formed by connecting ten narrow joints 111 each at the start end side and a terminal end side, and a large pitch portion 12 formed by connecting 98 large joints 112 each having a width of 50 mm) Applied. As shown in FIG. 5, the joint structure of the joint 21 and the second joint 22 at one end of the endless filter cloth 2 is engaged with the joint of the second joint 22 and the joint 21 at the other end so that two common holes are formed. Formed. The same two core wires 13 as in Example 1 were inserted through the common holes, and the endless filter cloth 2 was joined.

In the joint structure of Example 2, the mounting of the core wire 13 was completed in 20 minutes. When the joint part 21 of the endless filter cloth was visually confirmed, it was joined with almost no gap.

Next, the endless filter cloth 2 joined by the joint structure of Example 2 was used by being attached to the horizontal belt filter of FIG. FIG. 6 shows a known belt filter 4 that supplies slurry from a tank 41 onto an endless filter cloth 2. The endless filter cloth 2 is wound around a plurality of rolls 42 in a rotatable manner. One of the rolls is a drive roll 43, and the endless filter cloth 2 is rotated. A vacuum tray 44 is disposed inside the endless filter cloth 2, and moisture (filtrate) is sucked by the pump 45 and stored in the tank 46. On the other hand, the cake on the endless filter cloth 2 that has absorbed moisture is peeled off from the endless filter cloth 2 by the scraper 47. Thereafter, the endless filter cloth 2 is cleaned by the cleaning device 48. In the joint structure of Example 2, peeling of the cover during operation, which becomes a problem when the cover is covered on the joint with a hook-and-loop fastener, does not occur during operation, and the cake does not leak from the joint. .

[Comparative Example 1]
7480 metal joints 5 having a width of 0.5 mm are continuously connected to a joint portion of an endless filter cloth having the same size as that used in Example 1, and the metal joints 5 connected to both ends are engaged with each other. A common hole was formed, and the same core material as in Example 1 was inserted therethrough, and both ends of the endless filter cloth were joined (see FIG. 11). Since the joint structure of Comparative Example 1 has a small joint interval, it took 60 minutes to install the core wire 13 because the metal joint 5 was hooked or the core wire 13 was caught in the common hole. When the joined portion was confirmed, a gap of about 6 mm in width was formed along the longitudinal direction of the joined portion of the endless filter cloth.

When the endless filter cloth joined by the joint structure of Comparative Example 1 is used by being attached to the horizontal belt filter of FIG. 6, in the joint structure of Comparative Example 1 , the cover fixed on the joint portion by the surface fastener is in operation. It was necessary to peel it off and fix it again during the work. In addition, cake leaked out from the gap between the joints, and some contamination was observed in the filtrate.

[Aperture test]
Next, the joint structure shown in Table 1 in which the width (unit: mm) of the narrow joint 111 and the large joint 121 was changed (the material of the filter cloth and the woven cloth for forming the joint is the same as that of Example 1). A predetermined load was applied to the used filter cloth to check the opening of the joint. The test method is as described below (refer to the schematic diagram of FIG. 7 together). “Number of joint rows” in Table 1 indicates the number of joint structures. For example, in Example 1 (configuration of FIG. 1), the number of joint rows is “1 row”, and Example 2 (of FIG. 5) In the configuration, the number of joint rows is “2 rows”. The number of narrow joints in Table 1 is equal to the left and right. In the case of “total 10”, there are five narrow joints on the left ear and five on the right ear in the state where both ends of the filter cloth are joined. (Refer to the right and left ears in FIGS. 8 and 9).
1. The joint structure of each experimental example in Table 1 is stitched to a test filter cloth 51 made of the same material as the filter cloth used in Example 1 cut into a width of 30 cm and a length of 35 cm.
2. Two 1.5 mm polyester core wires are inserted through a common hole formed by engaging the joint structure, and the filter cloth is joined.
3. The suspended filter cloth is subjected to a load F of up to 10 kg on the lower part of the filter cloth by the spring balance 52, and the gaps (the left ear part, the central part and the right ear part) of the joint part 53 of the test filter cloth 51 ( Unit: mm) was measured and the deformation state was observed.
The measurement results are summarized in Table 2.

Furthermore, each part of the joint part 53 of the test filter cloth 51 over 7 days by applying a load F of 10 kg to the filter cloth of the same configuration joined using the joint structures of Experimental Examples 1 to 4 described in Table 1 ( The gaps (unit: mm) between the left ear part, the central part and the right ear part) were measured and the deformation state was observed. The measurement results are summarized in Table 3.

FIG. 8 shows the filter cloth of Experimental Example 3 immediately after applying a load of 10 kg, and FIG. 9 shows the filter cloth of Experimental Example 4 immediately after applying a load of 10 kg. FIG. 10 shows the filter cloth of Experimental Example 2 immediately after a load of 10 kg is applied. As is clear from FIGS. 8 to 10 and Tables 1 to 3, in the filter cloth joined by the joint structure of Experimental Examples 3 and 4 according to the present invention, the formation of a gap when a load is applied is suppressed to be small. I understand that. On the other hand, in Experimental Example 1, when a load was applied, the filter cloth was detached at the joint. In Experimental Example 2, as shown in FIG. 10, the right and left ears of the filter cloth warped at the joint, and the amount of gap formation was larger than in Experimental Examples 3 and 4.

DESCRIPTION OF SYMBOLS 1 Joint structure of endless filter cloth 11 Small pitch part 111 Small width joint 12 Large pitch part 13 Core wire 121 Large joint 2 Endless filter cloth 21 Joint part 22 Second joint part 3 Woven knitted cloth 31 Suture

Claims (2)

In a joint structure in which an endless filter cloth is formed by joining both ends of a filter cloth by inserting a core wire into a common hole formed by alternately engaging loop-shaped joints provided at joint portions at both ends of the filter cloth.
The joint structure includes a small pitch portion formed by connecting a plurality of small joints having a width of 3 to 10 mm to the joint portion, and a large pitch portion formed by connecting a plurality of large joints having a width of 20 to 100 mm to the joint portion. Have
The small pitch portion disposed at the junction of the starting end and the terminating side placing insert the core wire, and distribution of the large pitch portion between the small pitch portion,
The number of the narrow joints provided in the small pitch part is an endless filter cloth joint structure in which the number of the narrow joints is 2 to 20 per one small pitch part on the basis of the state where both ends of the filter cloth are joined . A second joint is further provided inside the joint at both ends of the filter cloth ,
The second joint, and the small pitch portion formed by continuously provided a plurality of narrow joint starting side and arranged on the end side 3~10mm width of the second joint portion is provided between the small-pitch portion 20 a plurality of substantially joint 100mm width and possess a large pitch portion formed by continuously provided,
2. The endless filter cloth according to claim 1, wherein the number of the narrow joints provided in the small pitch portion of the second joint portion is 2 to 20 per one small pitch portion on the basis of a state in which both ends of the filter cloth are joined . Joint structure.