JP2003093817A - Filter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a filter capable of eliminating the possibility of operational failure of a passage control device on the downstream, leakage of fuel gas, or the like, without incurring an increase in cost and an increase in passage resistance. SOLUTION: A single thin plate material formed into an expanded metal having a fine mesh is used as a raw material. The expanded metal is press- molded into a hat-shaped body as a filter unit 21 in which a central region 21 is convexed and an outer peripheral region 212 constitutes a flange portion. The outer periphery of the outer peripheral region is formed into a rugged shape, and this is bent by press-molding to for a fringe unit 22 constituted of protrusions 221 and notches 222. The filter unit 21 and the fringe unit 22 are formed as one united body by the raw material made of the expanded metal. The fringe unit is slightly stretched outward in a slanting direction, and press-pushed into the fuel gas passage of a combustion equipment, thereby causing an elastic deformation to exert an elastic restoring force on the surface of the inner wall of the fuel gas passage to attach the filter.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel passage for a gas fuel or a liquid fuel, a water passage, a passage for various media, etc. which are installed in a combustion equipment, a solar water heater, a jet bath device or various piping devices. , Is disposed on the upstream side of a fluid passage in which various valves such as an on-off valve and a flow control valve or passage control equipment such as a fluid actuating equipment such as a pump are provided on the downstream side of the passage, and fine dust or foreign matter To a filter used to block the inflow of

[0002]

2. Description of the Related Art Conventionally, in a combustion device such as an instantaneous water heater, the upstream end position of a fluid passage such as a fuel passage or a water passage, that is, a pipe for supplying fuel gas to the combustion device from the outside. It is usually practiced to dispose a filter at a position on the side of a connection end with a pipe for supplying water or water so as to prevent inflow of fine dusts. As such a filter, a braided wire mesh 90 as shown in FIG. 9 is used.
It is often used as a material. That is, a fine mesh braided wire mesh is used as a material to cut and form a filter having substantially the same shape as the inner cross section of the fluid passage, and the filter is formed and fitted into the fluid passage.

There is also known a filter in which the above-mentioned braided net is used as the material 90, and the tips of the individual wires protruding to the outer peripheral edge are embedded and integrated in a collar made of synthetic resin. For example, as in the example of FIG. 10, a collar portion 92 is integrally formed by resin molding so as to surround the outer periphery of a filter portion 91 made of a circular braided wire mesh. In this case, a plurality of projecting pieces 93 protruding from the collar portion 92,
93, ... Are integrally resin-molded and pushed into the fluid passage 1 (see FIG. 11) so that they are mounted (positioned) by the sliding frictional resistance with the inner peripheral wall surface 11.

[0004]

However, in the case of the above-mentioned conventional filter made of the braided wire net 90, the malfunction of the passage control device on the downstream side, and by extension, the malfunction of the combustion device,
There is a possibility that fuel gas leak or water leak may occur.

That is, in the braided net 90 which is the material of the filter, each of the wires 90a constituting the braided net 90 is independent from each other, and in addition, tension is applied during the manufacturing process and remains. The stress remains active. Therefore, there is a risk that the wire 90a will snap due to residual stress due to use over time, and if it breaks, the individual wires 90a will become independent and become small pieces that fall off the filter. It will be washed away downstream.

Here, in the combustion equipment, for example, an electromagnetic proportional valve for adjusting the gas flow rate up to the combustion burner at the downstream end of the fuel gas passage, and a switching valve for switching combustion of a plurality of burner heads. Etc. are interposed on the downstream side of the filter. When the small piece of the wire is flowed to the downstream side, the small piece is caught in the gap between the valve body and the fluid passage of the solenoid proportional valve, causing malfunction, or the switching valve is in the closed state. There is a possibility that it may enter the seal portion of the valve element and cause a seal failure. The above-mentioned defective operation tends to cause poor combustion control, and the defective sealing tends to cause fuel gas leakage.

In particular, in the case of a filter formed only of the braided net 90, the tip of the wire 90a protrudes from the outer peripheral edge of the filter, and the structure is prone to fraying and more susceptible to stress than other parts. The possibility of causing inconvenience also increases.

On the other hand, the wire tip at the outer peripheral edge is the collar portion 92.
In the case of a filter embedded in the resin molding part, although the wire tip does not fall off, it causes a significant cost increase in resin molding, and the resin itself after curing becomes a small piece shape. It is possible that they may fall out. That is, when the collar portion 92 is resin-molded, the collar portion 92 is formed during the molding.
At the boundary 92a (see FIG. 10 and FIG. 11) with the filter portion 91, the resin material squeezes out into each mesh of the braided wire mesh, and the squeezed state is cured. There is a possibility that the cured resin in the protruding portion may be broken or dropped into small pieces with use over time, and the small pieces of cured resin may flow to the downstream side to cause the same inconvenience as described above. In addition, the presence of the collar portion 92 narrows the passage cross-sectional area of the fluid passage 1, which also causes a fluid flow resistance. On the other hand, instead of the resin-molded collar portion 92, a braided wire mesh is expanded in diameter from the inner cross-sectional shape of the fluid passage 1, and the outer peripheral portion of this expanded diameter portion is raised to one side to form a cylindrical protrusion. It is also conceivable to fit this into the inner peripheral wall surface 11 of the fluid passage 1 using this as a collar portion. However, in this case, the circumference of the cylindrical protruding portion does not become a smooth cylindrical surface, and uneven bending wrinkles occur, and due to the bending wrinkles, a gap is formed between the cylindrical wall and the inner peripheral wall surface 11. It can be done, and the function as a filter becomes insufficient.

The present invention has been made in view of the above circumstances, and an object thereof is to prevent malfunction of a passage control device on the downstream side without increasing cost and distribution resistance. It is an object of the present invention to provide a filter capable of eliminating the possibility of fluid leakage.

[0010]

In order to achieve the above object, the present invention is directed to a filter arranged so as to block the upstream side of a fluid passage in which a passage control device is interposed in the fluid movement direction. Various inventions specified by the following claims are provided. Here, the "passage control device" installed on the downstream side is various fluid valves such as an on-off valve and a flow control valve, or a fluid actuating device such as a pump.

According to the first aspect of the present invention, the filter portion is formed by using a material formed of expanded metal having a fine mesh using a single thin plate material, and the outer peripheral portion of the filter portion is formed by the fluid passage. The inner peripheral wall surface is molded so as to be closely fitted.

According to the second aspect of the present invention, the filter portion is formed by using a single thin plate material formed of a punching metal having a large number of through holes of a fine diameter,
Further, the outer peripheral edge portion is formed into a shape that is closely fitted to the inner peripheral wall surface of the fluid passage.

Further, in the invention according to claim 3, slits at predetermined intervals in the circumferential direction are formed in multiple concentric circles at predetermined intervals in the radial direction with respect to a single thin plate material as a raw material, and the central portion is formed as described above. A substantially conical filter portion having a fine mesh is formed by pressing in the direction orthogonal to the thin plate member to open each slit at each of the concentric circle positions, and the outer peripheral edge portion of the thin plate member is defined by the fluid passage. The configuration is such that it is formed into a shape that is closely fitted to the inner peripheral wall surface.

According to the filter of any one of claims 1 to 3, since the entire filter is formed of an integral material, even if a part of the filter is broken, it cannot be separated from the filter. Without fail, the possibility of the small pieces falling off the filter flowing to the downstream side is reliably eliminated, and there is also the risk of malfunction of the passage control equipment on the downstream side and leakage of fluid such as fuel gas and water. Will be resolved. Moreover, each outer peripheral edge portion is formed into a shape that is closely fitted to the inner peripheral wall surface of the fluid passage, and the filter portion is formed of expanded metal having a fine mesh according to the first aspect. Is formed by a punching metal having a large number of through holes with a fine diameter, and
Since it has a fine mesh formed by pushing open each slit of the thin plate material, it can exhibit the function as a filter to the same level as or more than that of the conventional braided wire mesh. Particularly, in the case of claim 1 in which expanded metal is used as the material, since elasticity is exhibited as a whole, the mounting state in the fluid passage can be made stronger.

Here, in the filter according to the third aspect, the slit length and the slit interval of the slits formed in the thin plate material are set in the radial direction so that the mesh size of the filter portion formed by pressing is substantially uniform. It may be set to change (claim 4). For example, the slit length and the slit interval may be set to be smaller for a portion having a greater degree of expansion and opening by pressing. According to the fourth aspect, since the mesh of the filter portion formed in the substantially conical shape can be made substantially uniform, the function as the filter can be improved.

The outer peripheral edge portion of the filter according to any one of claims 1 to 4 is a substantially cylindrical shape which is bent in a direction substantially orthogonal to the filter portion and abuts against the inner peripheral wall surface of the fluid passage. It may be formed and the tip edge thereof may be formed in an uneven shape (claim 5). By doing so, the outer peripheral edge portion can be surely brought into close contact with the inner peripheral wall surface of the fluid passage. That is, since the leading edge of the outer peripheral edge portion is formed in a concavo-convex shape, bending wrinkles may occur even if the outer peripheral edge portion is bent and formed into a substantially cylindrical shape when the filter portion is circular. Therefore, it is possible to smooth the outer peripheral edge portion that is in contact with the both-end passages. As a result, it is possible to prevent the generation of the gap resulting from the generation of the bending wrinkles and to reliably exert the filter function, and it is possible to omit the collar portion formation by resin molding and avoid the cost increase.
In addition, the conventional resin-molded collar portion 92 (see FIG. 10 or FIG.
As described above), the passage cross-sectional area of the fluid passage is not narrowed, and thus the flow resistance of the fluid is not increased.

To form the filter according to claim 5,
As a material, a filter part may be set at the center of the filter part, and one having a shape having a plurality of projecting pieces protruding in the radial direction from the outer peripheral position of the filter part and being separated from each other in the circumferential direction may be used. It suffices (claim 6). For example, a material having a shape like a starfish is used. By doing so, even if the outer peripheral edge portion is bent into a substantially cylindrical shape, it becomes possible to more reliably suppress the occurrence of wrinkles,
The action of claim 5 can be obtained more specifically and surely.

Further, the outer peripheral edge portion of the filter according to the fifth or sixth aspect may be formed in a shape that is opened slightly obliquely outward (claim 7). That is, when the fluid passage and the filter portion are both circular, the base end of the outer peripheral edge has a diameter that matches the inner diameter of the fluid passage, but the diameter of the circle connecting the tips of the outer peripheral edge is greater than the inner diameter of the fluid passage. Is formed in a shape that is opened slightly obliquely outward so as to be slightly larger. When such a filter is fitted into the fluid passage with a slight press fit, the outer peripheral edge portion slightly elastically deforms inward in the radial direction, and this elastic reaction force (elastic restoring force) acts on the inner peripheral wall surface of the fluid passage. It will be installed in the condition As a result, relative movement of the filter is prevented, and mounting and position fixing in the fluid passage becomes more reliable.

The filter portion in the filter according to any one of claims 1 to 7 has a hat-shaped shape having a convex central portion, and the outer peripheral edge is the outer peripheral portion which is the hat-shaped collar portion. The part may be formed continuously (claim 8). In this case, even if fine dust is clogged in the central portion or the outer peripheral portion of the hat shape which is a surface orthogonal to the flow direction of the fluid flowing in the fluid passage, the hat shape rises substantially along the flow direction. It allows the passage of fluid from the site. That is, it is possible to secure a passage area for the fluid and increase the surface area of the filter portion while collecting the fine dust at a specific portion. Further, it is possible to increase the rigidity of the filter portion having the mesh and the through holes of the fine diameter.

[0020]

As described above, according to the filter according to any one of claims 1 to 8, since the entire filter is formed of an integral material, even if a part is broken. Can also be prevented from falling off from the filter, and it is possible to reliably eliminate the possibility that a small piece falling off from the filter will flow to the downstream side. As a result, it is possible to surely eliminate the possibility that the passage control device on the downstream side may malfunction due to the dropout of a small piece of the filter or the fluid may leak. Moreover, as a function as a filter, it is possible to exhibit the same or more than that of the conventional braided wire mesh. In particular, in the case of claim 1 in which expanded metal is used as the material, elasticity is exhibited as a whole, and the state of attachment to the fluid passage can be made stronger.

According to the fourth aspect, in the filter according to the third aspect, the mesh of the filter portion formed in the substantially conical shape can be made substantially uniform, and the function as the filter can be improved.

According to claim 5, in the filter according to any one of claims 1 to 4, even when the filter portion is circular, the outer peripheral edge portion is bent to be formed into a substantially cylindrical shape. The occurrence of bending wrinkles can be suppressed as much as possible,
It can be in close contact with the passages at both ends. As a result, it is possible to prevent the generation of gaps due to the occurrence of the above-mentioned bending wrinkles and to reliably exert the filter function,
It is possible to avoid the cost increase by omitting the collar portion formation by resin molding. In addition, the fluid passage is not narrowed and the flow resistance is not increased as compared with the case where the collar portion is formed by the conventional resin molding.

According to the sixth aspect, even if the outer peripheral edge portion is bent into a substantially cylindrical shape as in the fifth aspect, it is possible to more reliably suppress the generation of wrinkles, and the effect of the fifth aspect can be more concretely achieved. You can get it easily and surely.

According to claim 7, claim 5 or claim 6
In the above filter, the elastic restoring force from the outer peripheral edge portion can be applied to the inner peripheral wall surface of the fluid passage, thereby preventing relative movement of the filter and mounting and fixing the position in the fluid passage more reliably. It can be carried out.

According to the eighth aspect, in the filter according to any of the first to seventh aspects, while collecting fine dust at a specific portion, a passage portion for the fluid is secured and the surface area of the filter portion is increased. Also, the rigidity of the filter portion can be increased.

[0026]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, an embodiment in which the present invention is applied to such a combustion device will be described with reference to the drawings, which is intended for a combustion device having a fluid passage in which a passage control device is provided on the downstream side. Explain.

<First Embodiment> FIG. 1 is a sectional view showing a state in which a filter 2 according to a first embodiment of the present invention is mounted in a fluid passage 1 of a combustion device. The combustion device is, for example, an instantaneous water heater, and the fluid passage 1 is a gas passage for supplying fuel gas to the combustion burner of the water heater. The fluid passage 1 has a connection end for connecting a gas supply pipe from the outside near the upstream side (left side in the figure), and the downstream side (right side).
A combustion burner is located in the main gas via an electromagnetic on-off valve and an electromagnetic proportional valve for adjusting the flow rate of the fuel gas, and the fuel gas as a fluid flows from left to right.
The dashed-dotted line arrow in the figure indicates the flow of the fluid.

An inner peripheral wall surface 1 which is a cylindrical surface of the fluid passage 1.
1 is formed with a step portion 12 projecting toward the downstream side, and the filter 2 is pushed into the inside of the fluid passage 1 from the opening at the connection end of the fluid passage 1 toward the right side in FIG. It is adapted to be attached to (and the above points are the same in other embodiments).

As shown in FIG. 2, the filter 2 has a hat-shaped circular filter portion 21 having a convex central portion 211, and a substantially cylindrical stand-up on the outer peripheral side of the filter portion 21. The outer peripheral edge portion 22 and the outer peripheral edge portion 22 are integrally formed by using the expanded metal (see FIG. 3) formed from the same single thin plate material so as to have a fine mesh as the material 3. For example, a 0.2 mm thick stainless steel plate is used as a thin plate material, and a material formed into an expanded metal having a mesh with a short center distance of 0.9 mm and a long center distance of 1.0 mm is carved with a step width of 0.14 mm. .

The filter portion 21 is formed in a hat shape mainly for increasing the surface area of the filter portion 21 as much as possible and for collecting the fine dust to be collected at a specific portion (for example, the filter portion 21). Outer peripheral part 212
This is to collect in the ring part of.

The outer peripheral portion 212 of the filter portion 21 is formed so that its outer diameter matches the inner diameter of the step portion 12 of the fluid passage 1 on the large diameter side (for example, an inner diameter of about 30 mm).
The outer peripheral edge portion 22 is bent obliquely outward so as to be continuous with the outer peripheral portion 212, and has a shape that is opened so that its tip has a diameter slightly larger than the inner diameter. this is,
By pushing the filter 2 into the fluid passage 1, the outer peripheral edge portion 22 bends inward in the radial direction (see FIG. 1), and the inner peripheral wall surface 11 is mounted with an elastic restoring force applied. This is because

Further, the rising height of the outer peripheral edge portion 22 is set so as to alternately change in height so that unevenness is generated in the circumferential direction. That is, the outer peripheral edge portion 22 is formed such that the projecting piece portions 221 and the cutout portions 222 are alternately arranged in the circumferential direction. This is to prevent bending wrinkles from being generated in the outer peripheral edge portion 22 after the bending process described later. Moreover, the reason why a slight rising portion is left in the cutout portion 222 is to enhance the strength and to increase the roundness of the raised outer peripheral edge portion 22 as a whole. Although FIG. 2 shows an example in which four protrusions 221 and four notches 222 are formed, the number of protrusions 221 and notches 22 is not limited to this, and is three or five. May be more than one.

A procedure for manufacturing the filter 2 having the above structure will be described with reference to FIGS. 4 and 5. First, the material 3 having a predetermined shape is inserted and set between the male die 41 (see FIG. 4) for press-forming the filter portion 21 into a hat shape and the female die 42. As the material 3, as shown in FIG. 4, when the above-mentioned four projecting piece portions 221 and the notch portions 222 are formed, as shown in FIG.
It is a square with the size between 2 and 222 as one side,
In order to round the tip of each of the projecting piece portions 221, each corner is rounded. Then, the male die 41 is pressed against the female die 42 to form the intermediate processed material 3a in which the filter portion 21 is formed.
(See FIG. 5).

Next, the intermediate processed material 3a is inserted and set between the male die 51 for molding the outer peripheral edge portion 22 and the female die 52. The male mold 51 has a concave portion 511 for accommodating the central portion 211 of the filter portion 21, a donut-shaped contact surface 512 with which the outer peripheral portion 212 abuts, and a trapezoidal peripheral surface 513 for molding the outer peripheral edge portion 22. I have it. On the other hand, the female die 52 is formed with a recess having an inner peripheral surface 521 that matches the peripheral surface 513. As a result, by pressing the female die 52 toward the male die 51, the outer peripheral edge portion 22 having the protruding piece portion 221 and the cutout portion 222 is formed as shown by the alternate long and short dash line in FIG.

According to the filter 2 described above, since the whole is integrally formed of one expanded metal material 3, even if a part is broken, it can be prevented from falling off. it can. In addition, since the outer peripheral edge portion 22 is mounted on the fluid passage 1 in a state in which the elastic restoring force acts on the fluid passage 1 in addition to exhibiting the elasticity as a whole, the fluid passage is not required to be mechanically fixed. It is possible to firmly fix the position without deviating from 1. Moreover, since the outer peripheral edge portion 22 is formed by the projecting piece portion 221 and the notch portion 222, the generation of bending wrinkles is prevented, and the entire inner cross-section of the fluid passage 1 is formed without generating a gap due to bending wrinkles. Can be covered, and a reliable filter function can be exhibited.

<Second Embodiment> FIG. 6 shows a filter 6 according to a second embodiment of the present invention. In this filter 6, the filter portion 61 and the outer peripheral edge portion 62 are integrally formed by using one thin plate material (for example, a stainless steel plate having a thickness of 0.2 mm) as a material.

The filter portion 61 is composed of a substantially conical central portion 611 and an outer peripheral portion 612 that extends from the root position of the central portion 611 to the outer periphery. The central portion 611 has a fine diameter (for example, 0.5 to 1.
Porous portion 61 in which a large number of through holes 613 of 0 mm diameter) are formed
4 and a mesh portion 615 in which a fine mesh equivalent to that of the through hole 613 is formed at the slope position.
In addition, a large number of through holes 616 having the same diameter as the through holes 613 are formed in the outer peripheral portion 612 with a density corresponding to the mesh portion 615.

The outer peripheral edge portion 62 is the outer peripheral portion 6
A plurality of protruding piece parts 621, 6 rising from the outer peripheral position of 12
21, ..., and both protruding piece portions 621, 621 that are adjacent to each other in the circumferential direction.
Edges (corresponding to notches) 622, 622, ... Although FIG. 6 and FIG. 7 show an example in which the number of the projecting piece portions 621 is four, the number may be three or five or more. In addition, each of the protrusions 621
Is formed to open slightly obliquely outward as in the case of the first embodiment. Here, each of the projecting piece portions 622 has a shorter projecting dimension (rising dimension) than the projecting piece portion 221 of the first embodiment, and the edge portion 622 also projects much shorter than the cutout portion 222 of the first embodiment. It is a dimension.
This is because the difference in the degree of elastic deformation at the time of pushing and mounting in the fluid passage 1 (see FIG. 1) is taken into consideration due to the difference in material.

A procedure for manufacturing such a filter 6 will be described with reference to FIGS. 7 and 8. First, as shown in FIG. 7, a thin plate material is cut (for example, press-cut) so that the projections 621 (see FIG. 6) have portions 71, 71, ... Which project radially and have a starfish-shaped outer shape. Prepare 7. Then, a large number of through holes 613 are formed in the range of the porous portion 614 of the central portion of the material 7, and a predetermined outer peripheral portion 612 is formed except for the annular portion 72 which is the edge portion 622 (see FIG. 6). A large number of through holes 616 are formed at a predetermined density in the donut annular area.
12 and donut annular area 7 between the perforated portion 614
A plurality of arcuate slits (perforated cut lines) 74, 74, ... Having a predetermined length and a predetermined interval are formed by cutting in 3 in a multiple concentric circle arrangement.

Each of the slits 74 has the porous portion 614.
Are formed on concentric circles at predetermined intervals (for example, 0.2 to 0.3 mm) in the radial direction, and are formed out of phase with the slits 74 on the concentric circles that are adjacent to each other in the radial direction. Such slits 74, 74, ... May be formed with the same slit length and slit interval,
Preferably, the farther from the porous portion 614, that is, the closer to the outer peripheral portion 612, the shorter the slit length and the slit interval are formed. Particularly, in the vicinity of the bent portion with the outer peripheral portion 612, the slit length is longer than the others. To be formed. This is to make the mesh of the mesh portion 615 have a uniform size as much as possible when it is molded in the conical central portion 61 of FIG. This is to make a mesh of.

The material 7 which has been subjected to the above processing is shown in FIG.
Set in the female die 81 and pressed by the male die 82 as shown in FIG.
4 is pushed open to form a mesh portion 615, and a predetermined substantially conical central portion 611 is formed. Next, the outer peripheral edge portion 62
By pressing with the pressing die 83 for molding, the respective parts 71 and the annular part 72 are raised to mold the outer peripheral edge part 62 composed of the projecting piece part 621 and the edge part 622.

Also in the case of the filter 6 of the second embodiment described above, since the whole is formed integrally by using one thin plate material 7, even if a part is broken, it is broken. It can be prevented from falling off. Further, since each projecting piece portion 621 of the outer peripheral edge portion 62 is attached to the fluid passage 1 in a state in which the elastic restoring force acts on it as in the first embodiment, it is not necessary to apply mechanical fixing means. The position can be firmly fixed to the fluid passage 1 without shifting. Moreover, the outer peripheral edge portion 62 is connected to the projecting piece portion 621 and the edge portion 622.
Since it is formed by and, it is possible to prevent the generation of bending wrinkles, and to cover the entire inner cross section of the fluid passage 1 without generating a gap due to bending wrinkles, and to exert a reliable filter function. it can.

<Other Embodiments> The present invention is based on the first embodiment.
The present invention is not limited to the second embodiment and includes various other embodiments. That is, in the first embodiment, instead of the material 3 made of expanded metal, the material may be made of punching metal having a large number of through holes having a fine diameter equivalent to the mesh of the expanded metal. .

[Brief description of drawings]

FIG. 1 is an explanatory cross-sectional view of a state in which a first embodiment of the present invention is attached to a fluid passage.

FIG. 2 is a perspective view of the first embodiment.

FIG. 3 is a partially enlarged plan view of the material of the first embodiment.

FIG. 4 is an explanatory view showing the first half of the manufacturing process of the first embodiment.

FIG. 5 is an explanatory diagram showing the latter half of the manufacturing process of the second embodiment.

FIG. 6 is a perspective view showing a second embodiment.

FIG. 7 is a plan view showing a material after initial processing according to the second embodiment.

FIG. 8 is an explanatory diagram showing a manufacturing process of the second embodiment.

FIG. 9 is a partially enlarged view of a braided wire mesh that constitutes a conventional filter.

FIG. 10 is a perspective view of a conventional filter with a collar portion formed by resin molding.

11 is a cross-sectional explanatory view showing a state in which the conventional filter of FIG. 10 is mounted in a fluid passage.

[Explanation of symbols] 1 fluid passage 2,6 filter 3,7 material 11 Inner wall surface of fluid passage 21,61 Filter section 22, 62 outer peripheral edge 74 slits 211,611 Central part 212,612 Peripheral part 221 and 621 protrusion

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 3K068 AA01 AA11 AB16 EA02                 4D019 AA01 AA03 BA02 BB09 BC20                       CA10 CB06                 4D064 AA01 BA22 BA40

Claims (8)

[Claims] 1. A filter, which is arranged so as to block the upstream side of a fluid passage in which a passage control device is provided on the downstream side in the moving direction of a fluid, and which uses a single thin plate material to form a fine filter. Form the filter part using a material molded into expanded metal with a mesh,
A filter characterized in that its outer peripheral edge portion is formed into a shape that is closely fitted to the inner peripheral wall surface of the fluid passage. 2. A filter, which is arranged so as to block the upstream side of a fluid passage in which a passage control device is interposed in the downstream side in the moving direction of a fluid, and which has a fine diameter made of a single thin plate material. Of the punching metal having a large number of through holes, the filter portion is formed by using the material, and the outer peripheral edge portion is formed into a shape that is closely fitted to the inner peripheral wall surface of the fluid passage. A filter characterized by that. 3. A filter, which is arranged so as to block the upstream side of a fluid passage in which a passage control device is interposed on the downstream side in the direction of fluid movement, and which has a single thin plate material as a raw material. By forming slits at predetermined intervals in the circumferential direction in multiple concentric circles at predetermined intervals in the radial direction, pressing the central portion in the direction orthogonal to the thin plate material to open each slit at each of the concentric circle positions A filter characterized by forming a substantially conical filter portion having a mesh, and molding the outer peripheral edge portion of the thin plate material into a shape that is closely fitted to the inner peripheral wall surface of the fluid passage. 4. The filter according to claim 3, wherein the slit length and the slit interval of the slits formed in the thin plate material are set so that the mesh size of the filter portion formed by pressing is substantially uniform. A filter that is set to change with. 5. The filter according to claim 1, wherein the outer peripheral edge portion is bent in a direction substantially orthogonal to the filter portion and is in close contact with the inner peripheral wall surface of the fluid passage. A filter which is formed in a substantially tubular shape and whose tip edge is formed in an uneven shape. 6. The filter according to claim 5, wherein as a material, a filter portion is set in a central portion of the filter, and the outer peripheral position of the filter portion is apart from each other in the circumferential direction in the radial direction. A filter using a shape having a plurality of protruding pieces. 7. The filter according to claim 5 or 6, wherein the outer peripheral edge portion is formed in a shape that is opened slightly obliquely outward. 8. The filter according to any one of claims 1 to 7, wherein the filter portion has a hat-shaped shape having a convex central portion, and the outer periphery is a hat-shaped collar portion. A filter in which an outer peripheral edge portion is continuously formed at a portion.