WO2012053582A1

WO2012053582A1 - Fuel filter

Info

Publication number: WO2012053582A1
Application number: PCT/JP2011/074135
Authority: WO
Inventors: 植木　康志
Original assignee: 株式会社ニフコ
Priority date: 2010-10-21
Filing date: 2011-10-20
Publication date: 2012-04-26
Also published as: JP5575602B2; JP2012087725A

Abstract

A fuel filter includes: a filter member formed of a filter sheet into the shape of a sack; and a frame member arranged inside the filter member. The frame member has a plurality of frame ribs that press the filter sheet from the inside of the filter member toward the outside. The filter sheet has welded sections that fix together a plurality of nonwoven fabrics and woven meshes stacked in layers. The welded sections are formed at positions that come into opposition with the frame ribs.

Description

Fuel filter

The present invention relates to a fuel filter that filters fuel in a fuel tank.

Fuel in a fuel tank in an automobile or a motorcycle is usually supplied to the internal combustion engine through a fuel filter disposed in the fuel tank. As such a fuel filter, a filter using a bag-like filter member formed from a filter material sheet such as a mesh woven fabric or a non-woven fabric is known as described in Patent Document 1, for example.

The filter member described in Patent Document 1 has a filter material sheet that is double-folded at one fold, and a pair of sheet portions partitioned by the fold are welded at the edges to form a bag shape. Is formed. In addition, a frame member as a skeleton that separates the pair of sheet portions from each other is disposed inside the filter member formed in a bag shape. The fuel filtered in each of the pair of seat portions is temporarily stored in a filter member surrounded by the seat portions, and then supplied from the inside of the filter member to the internal combustion engine. According to such a structure, since the outer surface of a filter member is comprised by a pair of sheet | seat part, a filtration function comes to express in the substantially whole outer surface which a filter member has.

Japanese Patent No. 3353986

However, in the fuel filter described above, the filtration function is expressed in both the pair of sheet portions, but the filtration efficiency is low in the following areas (a) and (b) in the filter medium sheet. ing.

(A) Region of the filter member facing the frame member (b) Region of the filter member occupied by the weld portion In detail, the filter member described above is based on the fuel pressure in the fuel tank and the operation of the fuel pump. Due to the negative pressure in the internal space, the frame member is pressed. For this reason, although the filtration function appears on almost the entire outer surface of the filter member, it is difficult for the fuel to flow into the internal space of the filter member at the portion where the filter medium sheet and the frame member are in contact with each other. The filtration efficiency of the filter is lowered.

Also, in the fuel described above, a large number of foreign matters having different sizes such as water, metal powder, earth and sand are mixed. Therefore, a plurality of mesh fabrics and non-woven fabrics that are different from each other are also required for the filter material sheet constituting the filter member in accordance with the size of the object to be filtered. On the other hand, when a filter medium sheet is configured using a plurality of mesh fabrics or nonwoven fabrics, in order to prevent the positions of the laminated nonwoven fabrics from shifting from each other, a plurality of welds for fixing the laminated nonwoven fabrics to each other are provided on the filter member. It is necessary to form discretely throughout. For this reason, even in the welded portion thus welded, it becomes difficult for the fuel to flow into the internal space of the filter member, and as a result, the filtration efficiency of the fuel filter is lowered.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a fuel filter capable of increasing the efficiency of filtration.

The present invention includes a filter member formed in a bag shape by a filter material sheet, and a frame member disposed in the filter member, wherein the frame member has a plurality of frame ribs protruding toward the filter material sheet. The filter medium sheet is formed on each of the plurality of nonwoven fabrics so as to face each of the plurality of nonwoven fabrics stacked and the plurality of frame ribs, and welds the plurality of nonwoven fabrics to each other. A fuel filter having the gist of the above is provided.

In a preferred aspect of the present invention, the welded portion is formed in a concave shape on the inner surface of the filter member, and the frame rib has a facing surface that faces the welded portion, and the facing surface is outside the welded portion. The gist is to abut.

Here, when the laminated nonwoven fabric is welded by, for example, an ultrasonic welding method, the welded portion is recessed from its periphery by pressing of the welding jig and melting / solidification of the resin fibers. If the fuel filter vibrates in a state where the frame rib facing the welded portion enters the welded portion, a mechanical load is applied to the frame member and the filter member. In this regard, according to the frame rib of the preferred aspect described above, since the opposed surface of the frame rib that faces the welded portion is in contact with the outside of the welded portion formed in a concave shape, the frame rib is prevented from entering the welded portion. be able to. Therefore, a mechanical load on the frame member and the filter member can be suppressed.

In another preferred aspect of the present invention, the frame rib is provided with a plurality of abutting portions that abut on the outside of the welded portion.
According to this aspect, since the outer side of the welded portion and the plurality of contact portions are in contact, the contact area between the frame rib and the filter member as compared with the configuration in which the entire opposing surface of the frame rib is in contact with the filter member. Can be reduced. Therefore, the efficiency of filtration can be further increased.

In another preferred embodiment of the present invention, the filter member is formed in a flat shape along one surface, and the frame member has a base frame formed in a flat shape along the one surface. The gist of the present invention is that the frame rib protrudes from the base frame toward the filter medium sheet.

Like this aspect, a frame rib can be comprised by making it protrude toward a filter-medium sheet | seat from a base frame.
In another preferable aspect of the present invention, the frame member is formed so that the filter medium sheet is double-folded by one fold, and a pair of sheet portions partitioned by the fold sandwich the base frame. A pair of sheet portions are formed in a bag shape by welding at the edges of each other, the frame rib is formed only on one sheet portion side of the base frame, and the weld portion includes the base frame The gist of the invention is that each of the pair of sheet portions is formed so as to be plane symmetric with respect to the plane to be symmetric.

In a base frame sandwiched between a pair of seat portions, when a frame rib is formed only on one seat portion side of the base frame, the base frame itself is placed on the inner surface of the filter member on the other seat portion side of the base frame. It will abut. Therefore, on the other seat portion side of the base frame, in addition to the welded portion, the base frame also causes a reduction in filtration efficiency. In this regard, according to the above-described preferred embodiment, the welded portion is formed in each of the pair of sheet portions so as to be symmetric with respect to the base frame. Therefore, the welded portions formed on each of the pair of sheet portions face each other with the frame member interposed therebetween. That is, one of the opposed welded portions faces the frame rib, and the other faces the base frame. Therefore, the area that contributes to filtration can be further increased by the overlap of these areas, so that the efficiency of filtration can be increased.

According to the present invention, the welded portion of the filter member and the frame rib of the frame member face each other. Thereby, the area | region where the efficiency of filtration falls by a welding part and the area | region where the efficiency of filtration falls by a frame rib come to overlap. Therefore, in the region of the filter member excluding the welded portion, its filtering function is easily expressed, so that the filtration efficiency can be increased.

The figure which shows typically schematic structure of the fuel supply apparatus using the filter for fuels concerning one embodiment of this invention. (A) It is a perspective view which shows the perspective structure of the filter for fuels, Comprising: The figure which shows a part of internal structure of the filter member for fuels, (b) Sectional drawing which shows the cross-section of the filter-medium sheet | seat in a welding part. The perspective view which shows the perspective structure of a frame member. Sectional drawing of the cross-sectional structure of the fuel filter in the vicinity of the connecting portion. The expanded view of the filter medium which comprises a filter member. (A) Side view of frame rib, (b) Plan view of frame rib. The figure which shows typically the relationship between the overlap welding part of a filter member, and the bending part of a frame member.

Hereinafter, an embodiment of a fuel filter according to the present invention will be described with reference to FIGS. First, a fuel supply device using a fuel filter will be described. FIG. 1 is a diagram schematically illustrating a schematic configuration of a fuel supply apparatus.

As shown in FIG. 1, the fuel supply apparatus 10 is disposed in a fuel tank 11 in which fuel F is stored, a chamber 12 and a fuel pump 13 disposed in the fuel tank 11, and the chamber 12. And a fuel filter 20. The fuel filter 20 includes a filter body 21 that is configured to be bendable and filters the fuel F, and a connecting member 22 that is connected to the filter body 21. The filter body 21 is bent so that one end of the filter body 21 presses the bottom wall of the chamber 12, and is connected to the fuel pump 13 via the connecting member 22. The fuel pump 13 is connected to a supply pipe 15 fixed to the fuel tank 11 by a flange 14. When the fuel pump 13 is driven, the fuel supply device 10 filters the fuel F in the chamber 12 with the fuel filter 20 and supplies the filtered fuel F to the internal combustion engine 16 through the supply pipe 15. To do.

Next, the fuel filter 20 will be described in detail with reference to FIGS. FIG. 2A is a perspective view showing a perspective structure of the fuel filter. In FIG. 2A, a part of the fuel filter is notched for explaining the internal structure of the fuel filter. It shows the state that was released. FIG.2 (b) is sectional drawing which shows the cross-section of the filter material sheet in a welding part. FIG. 3 is a perspective view showing a perspective structure of the frame member. FIG. 4 is a cross-sectional view showing a cross-sectional structure of the fuel filter in the vicinity of the connecting portion.

2A, the fuel filter 20 has a filter body 21 extending in one direction and a connecting member 22 connected to one end of the filter body 21 in the longitudinal direction. The filter body 21 includes a filter member 24 formed into a flat bag shape by an upper sheet portion 23a and a lower sheet portion 23b facing each other, and a frame member 25 disposed in the filter member 24. .

The filter member 24 is formed of a single filter medium sheet 23 in which a plurality of sheet-like synthetic fibers are laminated. The filter member 24 has the above-described filter material sheet 23 that is double-folded at one fold, and the upper sheet portion 23a and the lower sheet portion 23b that are partitioned by the fold are welded at the edges of each other. Is formed into a bag shape. As shown in FIG. 2 (b), the filter medium sheet 23 of the present embodiment has a nonwoven fabric 26a formed of polypropylene fibers as an innermost layer, and a plain weave mesh fabric 27 that can separate oil and water. It has as an outer layer. Between these nonwoven fabrics 26a and the mesh fabric 27, the

nonwoven fabrics

26b and 26c are laminated | stacked so that the size of a mesh may become so small that it is located inside.

In the filter member 24 composed of such a filter material sheet 23, foreign substances having a large particle size are captured by the layer located on the outer side, and foreign substances having a small particle size are captured by the layer located on the inner side. That is, since foreign substances having different sizes are captured by different layers, clogging in each layer can be suppressed. In addition, if the nonwoven fabric formed by the spunbond method is used for the nonwoven fabric 26a which is the innermost layer, and the nonwoven fabric formed by the melt blown method is used for the

nonwoven fabrics

26b and 26c which are intermediate layers, relatively high rigidity is obtained. Since it is given to the nonwoven fabric 26a, generation of particles from the nonwoven fabric due to rubbing between the nonwoven fabric 26a and the frame member 25 can be suppressed.

The filter material sheet 23 is discretely provided with a plurality of welded portions 28 in which the

nonwoven fabrics

26a, 26b, 26c and the mesh fabric 27 are welded by ultrasonic welding from the nonwoven fabric 26a side which is the innermost layer. Each of the plurality of welded portions 28 is formed in a circular hole shape on the inner surface of the filter member 24. By forming such a welded portion 28, the laminated

nonwoven fabrics

26a, 26b, and 26c and the mesh fabric 27 are fixed to each other. Therefore, when the fuel filter 20 is used, it is possible to suppress the

non-woven fabrics

26a, 26b, 26c and the mesh fabric 27 from shifting from each other. Further, the filter medium sheet 23 can be cut out from the base material on which the

nonwoven fabrics

26a, 26b, 26c and the mesh fabric 27 are laminated, and further, the fuel filter 20 can be assembled in a state in which these are laminated.

The frame member 25 disposed in the filter member 24 is formed of a synthetic resin having flexibility. As shown in FIG. 3, the frame member 25 is a lattice-shaped base composed of a plurality of first frames 31 extending in the longitudinal direction and a plurality of second frames 32 extending in the short direction perpendicular to the longitudinal direction. A frame 30 is provided. The base frame 30 is provided with a frame rib 33 that protrudes toward the lower seat portion 23b at a location where the first frame 31 and the second frame 32 intersect. The frame rib 33 has its tip abutted against the inner surface of the filter member 24, and the tip pushes the inner surface of the filter member 24 to the outside of the filter member 24, thereby reducing the distance between the base frame 30 and the lower sheet portion 23 b. Hold. The frame rib 33 is formed to be larger than the weld portion 28 in a plan view facing the outer surface of the filter member 24, that is, in a plan view facing the lower sheet portion 23b (FIG. 5). reference).

Further, the base frame 30 has a connecting portion 35 to which the connecting member 22 is connected. The connecting portion 35 includes a substantially cylindrical flange portion 36 supported by the first frame 31 and the second frame 32, and a substantially cylindrical suction portion 37 extending from the flange portion 36 in the direction opposite to the frame rib 33. Have. Further, four suction ribs 39 projecting from the flange portion 36 toward the lower seat portion 23 b are equally arranged in the connecting portion 35 in the circumferential direction of the flange portion 36. The suction rib 39 is in contact with the inner surface of the filter member 24 to maintain a distance between the flange portion 36 of the connecting portion 35 and the lower sheet portion 23b, and the suction portion 37 is blocked by the lower sheet portion 23b. To prevent. As shown in FIG. 4, a part of the flange portion 36 in the connecting portion 35 is exposed to the outside of the filter member 24 through the through hole 40 provided in the upper sheet portion 23a. Further, the suction portion 37 in the connecting portion 35 protrudes outside the filter member 24 through the through hole 40.

The base frame 30 has a bent portion 41 extending over the entire width in the short direction of the base frame 30 on the side of the connecting portion 35 from the center in the longitudinal direction. The bent portion 41 is a portion in the base frame 30 where the interval between the adjacent first frames 31 and the interval between the adjacent second frames 32 are larger than those other than the bent portion 41. Each first frame 31 constituting the bent portion 41 is provided with a thin portion 42 having a small thickness so as to be arranged in the short direction. That is, the bent portion 41 is configured to have lower rigidity than the other portions, and is a portion that is bent preferentially over portions other than the bent portion 41 when an external force is applied to the frame member 25. . By providing such a bent portion 41, a mechanical load on the frame member 25 based on the external force can be reduced as compared with a frame member having a configuration in which the bent portion 41 is not provided.

According to the filter body 21 configured as described above, when the storage space 43 is in a negative pressure state by operating the fuel pump 13, the upper seat portion 23a is pushed to the outside of the filter body 21 by the base frame 30 itself. It is. Further, the lower sheet portion 23 b is also pushed to the outside of the filter body 21 by the frame rib 33 and the suction rib 39. Therefore, the space between the upper sheet portion 23a and the lower sheet portion 23b is maintained, whereby the storage space 43 is formed with a predetermined size between the upper sheet portion 23a and the lower sheet portion 23b. Then, the fuel F filtered by substantially the entire upper seat portion 23 a and substantially the entire lower seat portion 23 b flows into the suction portion 37 through the storage space 43.

4, the lower end portion 46 of the connecting member 22 is connected to the connecting portion 35 of the frame member 25, and the upper end portion 47 of the connecting member 22 is connected to the fuel pump 13 (see FIG. 1). A connecting passage 45 is formed in the connecting member 22 so as to penetrate from the lower end portion 46 to the upper end portion 47, and the suction portion 37 of the connecting portion 35 is inserted into the connecting passage 45 on the lower end portion 46 side. . The lower end portion 46 of the connecting member 22 is connected to the flange portion 36 in a state where the upper sheet portion 23 a is sandwiched between the flange portion 36 of the connecting portion 35 and the lower end portion 46. When the fuel pump 13 is operated, the fuel F that has flowed into the suction portion 37 is introduced into the fuel pump 13 through the communication passage 45 of the connecting member 22.

Next, the filter member 24 described above will be described in more detail with reference to FIG. FIG. 5 is a development view of the filter member 24 in which the filter member 24 is cut open at the portion where the upper sheet portion 23a and the lower sheet portion 23b are welded. The dot area in the drawing is a frame in the fuel filter 20. A region facing the rib 33 is shown.

When the fuel pump 13 is operated, the filter member 24 described above is pressed against the frame member 25 by the pressure of the fuel F in the fuel tank 11 and the negative pressure in the filter member 24. As a result, it is difficult for the fuel F to flow in a portion where the filter medium sheet 23 and the frame member 25 are in contact with each other. Moreover, the fuel F becomes difficult to flow also in the welding part 28 by which the synthetic fiber was welded among the filter media sheets 23. FIG. Therefore, according to the fuel filter 20 described above, the filtration function is expressed in both the upper sheet portion 23a and the lower sheet portion 23b. However, among the filter material sheets 23, the following (i) to ( In the area c), the filtration efficiency is low.

(A) Region of the lower sheet portion 23b facing the frame rib 33 (B) Region of the upper sheet portion 23a facing the base frame 30 (C) The welded portion 28 occupies the filter member 24 Region Therefore, in the present embodiment, as shown in FIG. 5, in the lower seat portion 23b, the frame rib 33 is arranged so that the welded portion 28 of the filter member 24 and the frame rib 33 of the frame member 25 face each other. The welded portion 28 is provided in accordance with the position. Further, in the upper seat portion 23a, the welded portion 28 is formed so that the welded portion 28 of the upper seat portion 23a and the welded portion 28 of the lower seat portion 23b are symmetrical with respect to the plane including the base frame 30 as a plane of symmetry. Is provided. Such a position of the welded portion 28 can be set as follows, for example.

That is, in a two-dimensional coordinate system parallel to the surface on which the base frame 30 extends, the positions of the plurality of frame ribs 33 are uniquely determined with the connecting portion 35 as a reference point. Further, the position of the connecting portion 35 and the position of the through hole 40 coincide with each other in the fuel filter 20. Therefore, by applying coordinate transformation such that the position of the connecting portion 35 and the position of the through hole 40 coincide with each other at the position of each frame rib 33, the position on the filter medium sheet 23 directly above the frame rib 33 and the frame rib A position on the filter medium sheet 23 facing 33 is determined.

If it is such a structure, the area | region where filtration efficiency falls by the welding part 28 of the lower sheet | seat part 23b and the area | region where filtration efficiency falls by the frame rib 33 will overlap.
In addition, a region where the filtration efficiency is reduced by the welded portion 28 of the upper sheet portion 23a overlaps a region where the filtration efficiency is lowered by the base frame 30 itself. That is, the area (c) overlaps the area (b) or the area (b). Therefore, in the region of the filter member 24 excluding the welded portion 28, the filtering function thereof is easily expressed, so that the filtration efficiency can be increased.

Next, the frame rib 33 of the frame member 25 will be described in more detail with reference to FIG. FIG. 6A is a side view of the frame rib 33. FIG. 6B is a plan view of the frame rib 33 and shows the position of the welded portion 28 with a two-dot chain line.

As shown in FIG. 6 (a), in the frame rib 33, on the facing surface facing the welded portion 28,

contact portions

54 and 55 are formed at both ends in the longitudinal direction. As shown in FIG. 6 (b), these

contact portions

54 and 55 are at least partially protruded from the welded portion 28 in a plan view facing the outer surface of the filter member 24, that is, the welded portion 28. It is formed so as to abut on the outside.

By forming the

contact portions

54 and 55 on the frame rib 33, the contact area with the frame rib 33 on the inner surface of the filter member 24 compared to the frame rib 33 on which the

corresponding contact portions

54 and 55 are not formed. Becomes smaller. That is, in the lower seat portion 23b, the area pressed by the frame rib 33 is reduced. Therefore, it can be suppressed that the fuel F hardly flows due to the frame rib 33.

As described above, the welded portion 28 is formed in a concave shape on the inner surface of the filter member 24. Therefore, if the fuel filter 20 vibrates with the

contact portions

54 and 55 entering the welded portion 28, there is a risk that a large mechanical load is applied to the frame member 25 and the filter member 24. is there. In this regard, in the present embodiment, the

contact portions

54 and 55 are formed so as to contact the outside of the weld portion 28. With such a configuration, the contact portion 54 (55) is prevented from entering the welded portion 28, so that a mechanical load on the frame member 25 and the filter member 24 can be suppressed.

Incidentally, in a filter member formed in a bag shape by welding the peripheral edge of the filter medium, it becomes difficult to weld the edge at a time when the side constituting the peripheral edge becomes long. As shown in FIG. 7, in the filter member 24, the long side 61 that is a peripheral part extending in the longitudinal direction and the short side 62 that is a peripheral part extending in the short direction are welded. Multiple weldings are performed when welding. And in order to eliminate the area | region which is not welded reliably in the long side 61 of the filter member 24, the said multiple times of welding is implemented so that the edge of the welding area | region formed by one time of welding may mutually overlap. Therefore, an overlap weld portion 63 in which the ends of the weld region overlap each other is formed on the long side 61 of the filter member 24. In the present embodiment, the peripheral edge is welded so that the overlapping weld 63 is formed at the center of the long side 61. That is, the peripheral edge portion is welded so that the overlapping weld portion 63 is formed at a position avoiding the bent portion 41 of the frame member 25 and adjacent to the bent portion 41.

Here, when the filter body 21 is bent, the restoring force based on the welding of the peripheral portion described above acts as a reaction force. And the restoring force of the said superposition welding part 63 with high rigidity in a peripheral part is larger than the thing of peripheral parts other than this superposition welding part 63. FIG. For this reason, if the superimposed welded portion 63 is formed so as to overlap the bent portion 41, the filter body 21 may be difficult to bend. On the other hand, according to the above-described configuration, the superimposed welded portion 63 is formed at a position adjacent to the bent portion 41. Therefore, when the filter body 21 is bent, the restoring force of the superimposed welded portion 63 is a reaction force. It becomes difficult to act as. Therefore, it is possible to smoothly perform the bending of the filter body 21.

As described above, according to the fuel filter 20 according to the present embodiment, the effects listed below can be obtained.
(1) According to the above embodiment, the welded portion 28 of the filter member 24 and the frame rib 33 of the frame member 25 face each other. Thereby, the area | region where the efficiency of filtration falls by the welding part 28 and the area | region where the efficiency of filtration falls by the frame rib 33 come to overlap. Therefore, in the region of the filter member 24 excluding the welded portion 28, the filtering function thereof is easily expressed, so that the filtration efficiency can be increased.

(2) According to the frame rib 33 of the above embodiment, since the facing surface of the frame rib 33 facing the welded portion 28 contacts the outside of the welded portion 28 formed in a concave shape, the frame rib 33 is attached to the welded portion 28. Can be prevented from entering. Therefore, a mechanical load on the frame member and the filter member can be suppressed.

(3) According to the above embodiment, since the outer side of the welded portion 28 and the plurality of

contact portions

54 and 55 are in contact with each other, compared to the configuration in which the entire opposing surface of the frame rib 33 and the filter member 24 are in contact. The contact area between the frame rib 33 and the filter member 24 can be reduced. Therefore, the efficiency of filtration can be further increased.

(4) According to the above embodiment, the welded portion 28 is formed on each of the pair of

sheet portions

23 a and 23 b so as to be symmetric with respect to the base frame 30. Therefore, the welding part 28 formed in each of a pair of sheet |

seat parts

23a and 23b opposes each other on both sides of the frame member 25. That is, one of the opposed welded portions 28 faces the frame rib 33 and the other faces the base frame 30. Therefore, the area that contributes to filtration can be further increased by the overlap of these areas, so that the efficiency of filtration can be increased.

(5) In the above embodiment, the superimposed welded portion 63 is formed at a position adjacent to the bent portion 41. Therefore, when the filter body 21 is bent, the restoring force of the superimposed welded portion 63 hardly acts as a reaction force. Therefore, it is possible to smoothly perform the bending of the filter body 21.

In addition, the said embodiment can also be implemented with the following aspects.
In the above-described embodiment, the filter member 24 is formed in a bag shape by bending one filter medium sheet 23 along the fold line 50 and welding the peripheral edge overlapping with the fold line 50. Not only this but the filter material sheet which has the welding part 28 in the position which opposes the frame rib 33, and the filter material sheet in which the through-hole 40 was formed are piled up mutually, and each peripheral part is welded. The structure in which a filter member is formed may be sufficient. Even with such a configuration, the same effects as described in the above (1) to (3) can be obtained.

In the above embodiment, the position of the welded portion 28 in the upper sheet portion 23a and the position of the welded portion 28 in the lower sheet portion 23b are plane symmetric with respect to the plane including the base frame 30. Not only this but the position of the welding part 28 in the lower sheet | seat part 23b can be changed suitably. For example, the position of the welded portion 28 in the lower sheet portion 23b may be a position facing the base frame 30 regardless of the position of the welded portion 28 in the lower sheet portion 23b. Even with such a configuration, the same effects as described in the above (1) to (3) can be obtained.

The frame rib in the above embodiment is formed so as to extend from the base frame 30 to the lower seat portion 23b side. However, the frame rib may be formed so as to extend from the base frame 30 toward the upper seat portion 23a. Alternatively, the frame rib may be configured by the rib extending from the base frame 30 toward the lower seat portion 23b and the frame rib 33 extending from the base frame 30 toward the upper seat portion 23a. At this time, the frame rib 33 extending toward the upper sheet portion 23a and the welded portion 28 of the upper sheet portion 23a may be configured to face each other. Even with such a configuration, the same effects as described in the above (1) to (3) can be obtained.

In the above embodiment, the end of the frame rib 33 has the

contact portions

54 and 55, but the

contact portions

54 and 55 may be omitted, and the end of the frame rib 33 may be formed as a flat surface. Even if it is such a structure, the effect similar to the effect described in said (1) (2) can be acquired. Or the structure by which three or more contact parts are formed in the front-end | tip of a frame rib may be sufficient.

In the above embodiment, the contact area that contacts the frame rib 33 in the inner surface of the filter member 24 is not the welded portion 28 but the outer side of the welded portion 28. Not only this but the contact area | region which contact | abuts with the frame rib 33 among the inner surfaces of the filter member 24 may be the welding part 28. FIG. Even if it is such a structure, the effect described in said (1) can be acquired.

The frame member 25 of the above embodiment has frame ribs 33 formed on the lattice-shaped base frame 30 as frame ribs. Not only this but a frame member should just form a storage space in a bag-like filter member. For example, the frame member 25 may be formed in a wave shape, and may be configured to push the filter member from the inner side to the outer side by the curved folded portion and to embody the folded portion as a frame rib. Even if it is such a structure, the effect described in said (1) can be acquired.

In the above embodiment, as shown in FIG. 5, a part of the plurality of welded portions 28 is formed to face the frame rib 33. By changing this, all of the plurality of welded portions 28 may be formed to face the frame rib 33. Such a configuration can further increase the efficiency of filtration.

A dot-like welded portion 28 is formed on the filter member 24 of the above embodiment. For example, the welded portion may have a shape extending in the short-side direction or a shape extending in the longitudinal direction. Moreover, what was welded from the outer side of the filter member 24, ie, the mesh fabric 27 side, may be used. Even if it is a welding part of such a structure, the effect similar to the effect described in said (1) can be acquired by forming a welding part so that a welding part and a frame rib may oppose.

In the above-described embodiment, the position of the weld portion 28 is set based on the position of the frame rib 33 formed on the frame member 25. By changing this, the frame rib 33 is formed so as to express the function of the frame rib 33 that forms a storage space in the filter member, and the function of the welded portion 28 that suppresses the displacement of the nonwoven fabric in the filter material sheet is expressed. As long as the welded portion 28 is formed as described above, the position of the frame rib 33 may be set based on the position of the welded portion 28, for example.

The filter sheet 23 of the above embodiment has a four-layer structure in which the

nonwoven fabrics

26a, 26b, 26c and the mesh fabric 27 are laminated. However, if a welded portion is formed, the filter medium sheet 23 has a two-layer structure, a three-layer structure, or 5 A laminated structure having more than one layer may be used.

The frame member 25 of the above embodiment has one bent portion 41. Not limited to this, the frame member 25 may have a plurality of bent portions.
In the above-described embodiment, the overlap welded portion 63 is formed at a central position of the long side of the filter member 24, that is, at a position different from the bent portion 41 of the frame member 25. By changing this, the overlapping welded portion 63 may be formed in the bent portion 41. In such a configuration, since the rigidity of the bent portion of the filter member 24 is increased, the user is prompted to bend the filter member 24 so that two regions sandwiching the bent portion 41 are bent with respect to the bent portion 41. It is possible. Further, it is possible to improve the restoring force of the filter member 24 when the bending is released.

The entire contents of the specification, claims, drawings and abstract of Japanese Patent Application No. 2010-236579 filed on October 21, 2010 are cited herein as disclosure of the specification of the present invention. Incorporate.

Claims

A filter member formed into a bag shape by a filter material sheet;
A frame member disposed in the filter member;
The frame member is
A plurality of frame ribs protruding toward the filter medium sheet;
The filter media sheet is
A plurality of laminated non-woven fabrics;
A fuel filter, comprising: a plurality of non-woven fabrics formed on each of the plurality of non-woven fabrics so as to face each of the plurality of frame ribs; and a weld portion that fixes the non-woven fabrics to each other.
The welded portion is
Formed in a concave shape on the inner surface of the filter member,
The frame rib is
The fuel filter according to claim 1, further comprising a facing surface facing the welded portion, the facing surface being in contact with an outside of the welded portion.
In the frame rib,
The fuel filter according to claim 2, wherein a plurality of abutting portions that abut on the outside of the welded portion are provided in a protruding manner.
The filter member is
Formed in a flat shape along one surface,
The frame member is
A base frame formed in a flat shape along the one surface;
The frame rib is
The fuel filter according to any one of claims 1 to 3, wherein the fuel filter protrudes from the base frame toward the filter material sheet.
The frame member is
The filter sheet is double-folded at one fold, and the pair of sheet portions are welded at the edges so that the pair of sheet portions partitioned by the fold sandwich the base frame. Formed in a bag shape,
The frame rib is
Formed only on one side of the seat portion of the base frame,
The welded portion is
The fuel filter according to claim 4, wherein the fuel filter is formed in each of the pair of seat portions so as to be plane-symmetric with respect to a plane including the base frame as a plane of symmetry.